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ANNO ACCADEMICO:2009/2010
2°ANNO CANALE: A
STUDENTE: Denise Di Bella
LA GESTIONE DELLA FERITA CHIRURGICA E LA SUA
GUARIGIONE
INTRODUZIONE
La pelle chiamata anche tegumento,è la copertura esterna del corpo. Essa fornisce le funzioni di
protezione,sensoriale e regolatrice. L'interruzione della normale integrità cutanea può interferire con
importanti funzioni della pelle. Una ferita è un interruzione dell'integrità cutanea. Un'incisione è un
tipo di ferita creata intenzionalmente come parte di un trattamento chirurgico. Il corpo risponde a
una ferita acuta o cronica mediante un complesso processo di riparazione chiamato guarigione.
L'infermiere ha un ruolo importantissimo nel prevenire un'alterata integrità cutanea e nel
promuovere una guarigione ottimale quando si verificano lesioni della cute o delle strutture
sottostanti.
Qualsiasi trauma alla pelle, come una ferita,crea un rischio di alterazione della funzione cutanea. Le
ferite possono essere divise in ferite accidentali e ferite chirurgiche.
Le ferite chirurgiche variano da semplici e superficiali a profonde e contaminate. La gravità della
ferita determina la durata della guarigione,il grado di dolore,la probabilità di complicanze nella
ferita e la presenza di qualsiasi sonda,drenaggio o presidio in aspirazione. Le ferite guariscono in
modo diverso in base a dove si è verificata la perdita di tessuto. I principali tipi di guarigione delle
ferite sono:guarigione per prima,seconda e terza intenzione.
Le ferite con minima perdita tissutale,come un'incisione chirurgica pulita,o ferite poco profonde
suturate;guariscono per 1°intenzione.In quanto i bordi della ferita primaria sono approssimati o
avvicinati.
Il tessuto di granulazione non è visibile e la cicatrice è minima. Il rischio di infezione è più basso
quando una ferita chirurgica pulita guarisce per 1°intenzione. I fattori che influiscono sulla
guarigione delle ferite possono essere fattori sistemici,come la nutrizione,la
circolazione,l'ossigenazione e la funzionalità delle cellule immunitarie. I fattori individuali,ad
esempio l'età, l'obesità, il diabete, l'anamnesi positivo per il fumo e la terapia con farmaci possono
inoltre influenzare la velocità di guarigione di una ferita.
Anche i fattori locali come la natura e la localizzazione della lesione,la presenza di infezione e il
tipo di medicazione utilizzata.
Una lesione dell'integrità cutanea,dovuta sia a un'incisione chirurgica sia a un trauma accidentale
costituisce una porta di ingresso nel corpo per i microrganismi. Se le difese della persona sono
inadeguate,la contaminazione batterica della ferita può esitare in un'infezione. La probabilità di
infezioni della ferita dipende dai seguenti fattori: fattori locali:contaminazione,grado di
chiusura,presenza di corpi estranei,fattori di trattamento:tecnica chirurgica,condizioni
ambientali,fattori dell'ospite:età della persona,stato nutrizionale,problemi di salute cronici,virulenza
dell'organismo.
Le basi scientifiche delle strategie per la guarigione delle ferite hanno fatto importanti progressi
negli ultimi 20 anni. Per garantire una guarigione ottimale delle ferite deve essere mantenuto un
ambiente umido e questa scoperta ha condotto alla produzione di medicazioni per la cura delle ferite
che applicano questo principio scientifico. In passato la maggior parte delle medicazioni erano
garze asciutte o bagnate e le ferite venivano pulite con prodotti che si sono poi rivelati tossici per le
cellule all'interno delle ferite.
L'infermiere partecipa alla scelta di medicazioni appropriate,tale scelta deve essere basata sulla
valutazione della ferita e sul principio della guarigione in ambiente umido. Altri fattori che
influenzano la scelta della medicazione sono collegati alla quantità e tipo di drenaggio, alla
presenza di tessuto necrotico,infezione, tunnelizzazioni, fistolizzazioni e localizzazione della
lesione. L'infermiere ha come compito importantissimo di prestare
attenzione alla guarigione della ferita,ai cambiamenti della superficie della lesione e valutare
eventuali necessità di modifiche del tipo di medicazione e della frequenza delle stesse.
Le medicazioni possono essere usate per: assorbire il drenaggio,prevenire contaminazione,prevenire
danni meccanici alla ferita,aiutare a mantenere la pressione in modo da evitare il
sanguinamento,creare un ambiente umido per la ferita,provvedere al benessere dell'assistito. Le
medicazioni possono essere classificate in ampie categorie,sulla base delle loro caratteristiche e
indicazioni,possono essere: film
trasparenti,schiume,idrocolloidi,idrogel,alginati,collagene,composite,strati di contatto,medicazioni a
base di argento. Con lo sviluppo delle conoscenze sulla microbiologia delle ferite,sono aumentati i
prodotti derivati da cute e tessuti artificiali,fattori della crescita,medicazioni in matrice extracellulari e sottomucosa intestinale suina.
Questa ricerca vuole valutare se l'utilizzo di medicazioni avanzate sia migliore delle medicazioni
tradizionali per trattare il processo di guarigione della ferita chirurgica.
OBIETTIVO
L'obbiettivo della mia ricerca è quello di verificare se in letteratura vi siano prove che l'utilizzo di
medicazioni avanzate rispetto alle tradizionali porta a una migliore risoluzione della ferita
chirurgica,indagando anche se il tipo di medicazione scelta migliora la compliance del paziente cioè
minor dolore durante il cambio della medicazione,comfort e soddisfazione. Questa ricerca a livello
assistenziale ha come scopo il miglioramento della guarigione della ferita chirurgica,utilizzando le
adeguate medicazioni e prevenendo le eventuali complicanze come ad esempio la infezione della
ferita che aumenta notevolmente i costi dell'assistenza medica e può allungare in modo sensibile il
tempo di recupero.
STRATEGIA DI RICERCA
P = Paziente con ferita chirurgica
I = Utilizzo di medicazione avanzata
C = Altri utilizzi di medicazioni tradizionali
O = Risoluzione della ferita
Compliance del paziente
Costi sostenuti.
Parole Chiave: advanced surgical wound dressings
Search
Ovid MEDLINE(R) 1950 to May Week 5 2009
# Searches Results 1 Surgical wound dressings {No Related Terms} 872
History:
2 Surgical Procedures, Operative/ec, co, ut, mt, ct, nu [Economics, Complications, Utilization,
Methods, Contraindications, Nursing] 7508
3 Medicare Part B/ or Medicare/ 27660
4 3 and 2 126
5 Hospitalists/ or Technology, Medical/ or Technology, High-Cost/ or Emergency Medicine/ 18734
6 use of advanced dressings in the treatment of surgical wound {No Related Terms} 10131
7 advanced surgical wound dressings {No Related Terms} 31
8 from 7 keep 2, 15, 26 3
9 from 8 keep 1-3 3
10 from 8 keep 1-3 3
11 from 10 keep 1-3
RISULTATI RICERCA BIBLIOGRAFICA
-1. Gestione della ferita chirurgica: il ruolo delle medicazioni.
Nursing Standard.15(44):59-62,64,66,2001 lug 18-24
(Case Reports.Gazzetta articolo. )
-2. Gestione della ferita infetta:tecnologie avanzate,trattenere l'umidità,medicazioni,e die-hard
metodi
Critical Care Nursing Quarterly.24(2):64-77;quiz 2p seguenti 77,agosto 2001
( Gazzetta articolo)
-3 Gestione delle complicanze della ferita da parto cesareo
Critical Reports (21-23), 2003
(articolo di giornale)
CRITERI DI SCELTA DELL’ARTICOLO
Ho selezionato questi tre articoli dopo aver letto e preso in esame l'abstract,ho cercato solo gli
articoli pertinenti e rilevanti per rispondere al quesito. Questi tre articoli sono quelli che si
avvicinano di più a ciò che chiede la mia ricerca.
ANALISI DEGLI ARTICOLI
-1 ARTICOLO
Titolo: Gestione della ferita chirurgica:il ruolo delle medicazioni.
-2 ARTICOLO
Titolo: Gestione della ferita infetta:tecnologie avanzate,di trattenere l'umidità,medicazioni,e diehard metodi.
-3 ARTICOLO
Titolo: Gestione delle complicanze della ferita da parto cesareo
I titoli dei tre articoli scelti sono specifici e coerenti in quanto focalizzano in modo chiaro gli
argomenti della ricerca.
L'abstract dei tre articoli riassumono in modo comprensibile gli obiettivi,i metodi ed i risultati della
ricerca, rendendo l'idea di ciò che sarà trattato negli articoli.
Il metodo del 1° articolo è basato sullo studio del processo di guarigione di due pazienti con ferita
chirurgica. Mentre per quanto riguarda il secondo articolo non presenta una metodologia di ricerca
vera e propria,ma evidenzia in modo specifico le categorie di medicazioni,e riporta dati generali di
alcuni studi.
I risultati del 1° articolo indicano che l'utilizzo delle medicazioni avanzate sia il metodo migliore
per garantire un processo ottimale di guarigione e comfort per il paziente. Questi risultati sono
riportati in modo esplicito e coerente con lo scopo della ricerca.
Anche i risultati del 2° articolo indicano come metodo migliore l'uso di medicazioni avanzate
soprattutto quelle medicazioni a base d'argento e iodio.
Il 3° articolo tratta nello specifico la gestione della ferita post-parto cesareo, dalla prevenzione al
trattamento per accelerarne la guarigione.
DISCUSSIONI
I tre articoli mettono in evidenzia l'importanza della gestione della ferita,utilizzando medicazioni a
base di argento e iodio ,come è stato dimostrato nei due casi presi in considerazione nel primo
articolo,in quanto questi tipi di medicazioni possono avere un impatto enorme nel processo di
guarigione della ferita.
In tutti gli articoli risaltano il ruolo fondamentale che ha l'infermiere nella scelta di medicazioni
appropriate,scelta che deve essere basata sulla valutazione della ferita e sul principio della
guarigione in ambiente umido,utilizzando medicazioni avanzate piuttosto che quelle tradizionali.
Il primo articolo a differenza del secondo, oltre ad evidenziare l'importanza delle
medicazioni,ritiene necessario che ci sia un coinvolgimento da parte del paziente rendendolo
partecipe nella scelta di una strategia per un processo di guarigione ottimale prevenendo eventuali
complicanze.
Il terzo articolo integra i primi due articoli esaminando la ferita post-parto cesareo che ho potuto
riscontrare durante il tirocinio in ginecologia.
CONCLUSIONI
Gli articoli trovati per rispondere al mio quesito sono stati esaurienti,giungendo alla conclusione
che le medicazioni avanzate possono costituire una valida ed efficace alternativa alla medicazioni
tradizionali. In quanto dopo l'uso di medicazioni avanzate,il gradimento del paziente risulta
migliorato,e i costi sostenuti sono a volte inferiori a quelli delle medicazioni tradizionali.
Dopo la lettura e analisi critica degli articoli scelti da me,posso affermare che in letteratura sono
presenti prove che sostengano la maggior efficacia delle medicazioni avanzate rispetto alle
tradizionali nella risoluzione della ferita chirurgica;come è accaduto nello studio dei due casi
presentati dal primo articolo,dove l'utilizzo delle medicazioni avanzate hanno portato alla
guarigione della ferita garantendo il comfort del paziente.
ARTICOLO 1
Surgical wound management: the role of dressings
Watret, Lynne MN, MA, RGN; White, Richard MI Biol, PhD
Author Information
Lynne Watret MN, MA, RGN, is Senior Tissue Viability Nurse, North Glasgow Hospitals NHS
University Trust.
Richard White MI Biol, PhD, is Clinical Research Consultant and Freelance Medical Writer,
Whitstone, Cornwall. Email: [email protected]
Date of acceptance: May 7 2001.
Online archive: For related articles visit our online archive at: www.nursing-standard.co.uk and
search using the key words below.
These key words are based on subject headings from the British Nursing Index. This article has
been subject to double-blind review.
Summary
The history of surgical wound management illustrates how dressings have evolved over
the years and sets the scene for modern wound-healing products. The aim of this article is
to discuss the management of surgical wounds and the value of wound-healing products
for carers and patients in the current healthcare climate of cost-efficacy and clinical
governance.
UNTIL THE discovery of moist wound healing and resultant wound dressings in the latter
part of the 20th century, there had been few advances in wound management. Since the
1800s, advances in the treatment of wounds have largely been due to military surgery limb amputation and repair of gunshot and shrapnel wounds - and the pioneering
antisepsis research of Lister, Pasteur and Semmelweiss (Lawrence 1994). These
advances drew attention to the need for clean dressings and sterility - lint, gauze and
cotton rapidly replaced non-sterile dressings. In the second half of the 19th century, a
surgeon called Gamgee developed an absorbent and antiseptic surgical dressing that we
know and recognise today as Gamgee tissue. This innovation established wound care as
a discipline almost exclusively confined to surgical wounds and the domain of surgeons.
The next major advance occurred in the 1960s when Winter (1962) defined the principle of
moist wound healing. This work led to a new generation of dressings, including films,
hydrocolloids and foams. With the development of these new dressings, the focus of
wound care shifted towards chronic wound management - an area that had been hitherto
overlooked. While some areas of surgery - notably burns and plastics - had eagerly
adopted the new dressings, other areas continued to use dry, gauze-based materials
(Chaloner et al 1996, Moore 2001, Moore and Foster 1998a). Over the past 30 years,
advances in wound care and understanding the physiology of the wound have largely
resulted from the attention given to chronic wounds, the dressing industry and the adoption
of wound care as a predominantly nurse-led discipline (Krasner and Sibbald 1999,
Vowden et al 1996).
The management of surgical wounds - whether closed with sutures to heal by primary
intent or left open to heal by secondary intent - still involves the use of dry dressings, such
as cellulose, plain gauze and paraffin-impregnated gauzes. However, these dressings are
prone to adhere to the surface of the wound and cause pain and trauma on removal
(Bennett and Moody 1995). It has been suggested that dressings are not required on
sutured and stapled wounds 24 hours post-operatively (Chrintz et al 1989), as infection
rates are no different to similar wounds dressed until suture removal. However, these
findings are not consistent with those of Holm et al (1998), who compared a hydrocolloid
with a conventional dressing on closed surgical abdominal wounds. The authors found a
lower infection rate and greater patient preference on the basis of comfort and mobility in
the hydrocolloid group. The dressing of open or closed surgical wounds with conventional
non-adherent knitted viscose dressings and absorbent perforated plastic film-faced
dressings leads to patient pain and discomfort, as these dressings regularly adhere to
dried blood and exudate on the wound surface.
Dressing surgical wounds in theatre is largely the dictate of the surgeon. Since most
surgical wounds are sterile, and inflicted on otherwise healthy tissue, healing is not usually
compromised, as would be the case in a chronic wound where heavy bacterial colonisation
and underlying pathology adversely influence healing. However, this does not absolve
those charged with the management of surgical wounds from considering the needs of the
patient and optimum use of modern dressings.
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Patient-focused wound care
Accurate and detailed assessments are the basis of good wound care. Assessment is an
integral part of the wound management process and should reflect a holistic and
multidisciplinary team approach (Bennett and Moody 1995). The assessment framework
provided by Bennett and Moody aims to ensure that the patient and the wound are treated
appropriately according to the nursing model developed by Roper et al (1985). Nurses
should undertake a holistic assessment of surgical patients pre-operatively to establish
any potential barriers to post-operative wound healing, such as poor nutritional status,
obesity and diabetes, and to optimise the patient's condition as early as possible. Nurses
should aim to plan patient care before the operation takes place and the following aspects
should be considered:
[black small square] The type of wound - whether the wound will be closed by suturing and
left to heal by primary intent - or left open to heal by secondary intent - a cavity which
might have a drain in situ.
[black small square] Wound location - consideration should be given to whether the wound
will be on a flexor or extensor surface, whether it will impede patient mobility or be in an
area where natural movement is likely to cause skin tension and increase the risk of
dehiscence, for example, the axilla, neck, or abdomen. Pressure and contamination are
likely to cause problems with healing in the perineum and ano-genital regions.
[black small square] The amount of exudate anticipated and how this will be managed.
[black small square] Dressing selection - the use and function of dressings and how these
will be used in individual patients.
In a non-complicated post-operative wound dressing, selection might be straightforward;
however, this process becomes more complex when managing open or infected wounds.
It is important to remember that the status of the wound can change rapidly and wound
assessment should be ongoing and carried out at regular intervals. Nurses should
consider whether or not the most appropriate dressing has been selected and whether it is
being used appropriately, or whether the dressing regimen needs to be revised as healing
progresses or deteriorates.
It is unlikely that aspects of wound care, such as comfort, pain on dressing change and
freedom to bathe, are paramount when wounds are first dressed in theatre. The
widespread use of dressings such as proflavine-impregnated gauze in the packing of
excision wounds left to heal by secondary intent is testimony to this (Foster and Moore
1997a and b). The use of such materials in dressing surgical cavities often results in
extreme discomfort and inconvenience to the patient. These dressings harden in the
wound cavity and need to be soaked before removal, which is often done under general
anaesthesia, or using potent analgesia, such as pethidine.
Research on modern dressings has clearly demonstrated that pain on dressing change
need no longer be endured (Hollinworth and Collier 2000). In the UK, the Royal College of
Surgeons has issued a report on post-operative pain which states that: '...failure to relieve
pain is morally and ethically unacceptable' (RCS 1990). Although this statement refers to
pain management in general, care should be taken to minimise pain on dressing wounds
and each patient needs to be individually assessed. Where evidence indicates that
measures can be taken to lessen or relieve pain and discomfort as a result of wounds,
these should be implemented throughout the wound management process. Although the
report focuses on methods of assessment and drug treatment, sufficient evidence exists to
recommend that certain dressing regimens should be used (Thomas 1997a) while others
should not be used (Martini et al 1999).
Surgical wound assessment is an ongoing nursing responsibility that should be conducted
regularly at dressing changes until the wound is fully healed. There are many tools
available to assist in wound assessment (Thomas 1997b), and all focus on the following
elements:
[black small square] Type of wound - superficial or cavity.
[black small square] Age of wound - fresh, days or weeks, dehisced.
[black small square] Stage of healing - for example, granulating, or epithelialising wounds.
[black small square] Progress - healing, deteriorating, necrotic, infected, or static
The requirements for ideal wound dressings were first proposed by Turner (1985) and
subsequently expanded on by Morgan (1998). Since then, numerous advances have been
made both in terms of dressings and in our understanding of the healing process. There
has been a move towards longer wear time, particularly when dressing chronic wounds,
such as leg ulcers, in community settings. Longer wear times have been encouraged by
the dressings industry in an attempt to demonstrate cost-effectiveness. The result has
been that the expectation of seven days wear time has left some patients with leaking
dressings and tissue maceration. In general surgical wound care, both in the immediate
post-operative period when the patient is in hospital and in the recuperation period when
the patient might be at home, it is unwise to extend wear time beyond the capability of the
dressing regimen. The undesirable sequelae of strike-through, infection, maceration and
risks of skin breakdown or dehiscence should be avoided by regular assessment of the
wound at each dressing change, and by careful and informed selection of dressings based
on the needs of the patient and wound healing requirements. The criteria for surgical
wound dressings and dressing combinations are listed in Box 1.
These criteria cannot currently be met by using a single dressing, but dressing
combinations have been demonstrated to fulfil most, if not all, of these elements. The case
studies illustrate that through careful wound assessment and dressing selection,
combinations of dressings can address individual patient needs, while simultaneously
promoting an optimum wound-healing environment.
Conformability A conformable dressing is essential for patient comfort and mobility,
whether the wound is closed or left open. In the case of open wounds, such as pilonidal
sinus and abscess excisions, or perineal wounds, dressing conformability is important. A
soft and conformable primary dressing will permit gentle filling of the surgical cavity without
trauma or pain. Alginates (Thomas 2000) and hydrofibre dressings (Benbow and Losson
2000, Robinson 2000) have been found to be particularly effective as primary dressings.
Cohesive Some, but not all, fibrous dressings fall apart when they become wet with
exudate. The lack of cohesive strength makes the process of insertion into, and removal
from, the wound difficult and time consuming. It is preferable to select a dressing with high
wet and dry cohesive strength, such as hydrofibre dressings and some alginates, for use
on exuding wounds (Foster et al 2000).
Non-adherent and non-toxic Dressing adherence to the wound and surrounding tissues
presents a problem for practitioners and patients in terms of pain and trauma to the wound
(Emflorgo 1999, Williams 1996). Adhesion to the wound can be avoided through the use of
correct surgical and nursing approaches, and appropriate dressing selection (Moore and
Foster 1998a and b). Regulated dressing development has meant that the issue of toxicity
is no longer a major problem, as dressings that bear the European 'CE' mark are not toxic
according to the limits of the prescribed tests. However, toxicity remains an issue with
some dressings, antiseptic solutions and wound treatments (White et al 2001).
Absorbent As most surgical wounds produce exudate, particularly in the early stages of
healing (Hulten 1994), primary and secondary dressings that absorb exudate should be
used. Practitioners should not always rely on primary dressings to absorb exudate;
absorbent secondary dressings can also help to prevent skin maceration (Watret 1997).
The recent development of dressings that absorb and retain exudate (White 2001a and b),
while maintaining a moist environment, also help to avoid skin maceration (Cutting 1999).
Permit bathing The use of occlusive secondary dressings, such as hydrocolloids (regular
and thin varieties), films and adhesive foams, protects the wound site, permits bathing and
has the added benefit of avoiding contamination (Dealey 1993).
Moist environment The theory of moist wound healing (Winter 1962) has stood the test of
time (Field and Kerstein 1994). A moist wound environment promotes autolytic
debridement and enables re-epithelialisation. Moist wound healing dressings are, in
general, easier to remove from the wound and cause less trauma on removal than
traditional gauze-based dressings. A dry wound will also heal more slowly (Winter 1962).
Easy to use Dressings or dressing regimens that are easy to use are important, not only
for professional healthcare staff, but also for patients and informal carers. Dressings that
fall into this category encourage good wound management as they rarely adhere to the
wound bed, do not disintegrate - necessitating irrigation from the wound on removal - and
are less time consuming and easier to apply than traditional wound dressings (Maxwell
1998, Moore 2001, Moore et al 1999). Following demonstration and education, such
dressings provide an opportunity for patients and carers to change dressings at home,
which promotes independence and dignity, and means that patients and carers do not
always have to depend on others to renew their dressings.
Avoid cross-infection The bacterial and viral barrier properties of some dressings have
been known for some time (Bowler et al 1993). More recently, studies have shown that
dressings can reduce the dispersal of contaminating organisms into the air on removal
from the wound (Lawrence 1994), while others can absorb bacteria into their structure,
thus reducing the numbers available for possible cross-infection (Bowler 2001, Bowler et al
1999).
Community availability During the last five years many more dressings have become
available in hospital formularies and on the Drug Tariff. This is, in part, the result of
increasing clinical evidence that supports the use of such dressings. The availability of
specific dressings in the community should be considered during wound assessment,
particularly as patients are being discharged earlier from acute settings.
Cost-effectiveness Numerous studies on chronic wounds have focused on costs and
economic analyses. Measurements of healing rates, wear times and the time taken by
nurses to change dressings have been used to derive these data (Harding et al 2000). In
an environment where resources are limited, it is important to be aware of any evidence of
cost-effectiveness. On reviewing surgical practice in one hospital, Moore and Foster
(2000) found that appropriate choice of dressings led to substantial cost savings by
reducing bed occupancy times and, in some instances, permitting day-case surgery to
take place where otherwise an overnight stay would be expected.
Patient empowerment As a direct result of the current trend in early patient discharge from
hospital, and the competition for community healthcare resources, selected patients or
their relatives might be entrusted with conducting their own dressing changes at home.
The decision to permit this depends on many factors, such as the ease of dressing change
and patient independence and ability. Such a system 'empowers' patients and promotes
decision making and freedom of choice in wound care, while decreasing dependency on
health professionals.
Infection control Nosocomial infections are a major global healthcare problem. In the UK,
as many as 100,000 people are affected annually at a current cost of £1 billion. This
problem is exacerbated by the spread of antibiotic-resistant pathogens, such as methicillinresistant Staphylococcus aureus (MRSA). More antibiotic-resistant bacteria exist and are
spread in hospital than elsewhere (Bowler 2001). As it is preferable to prevent infection
rather than treat it, precautions and practices designed to reduce cross-infection should be
adopted. The spread of infection can be controlled by:
[black small square] Skin preparation before surgery.
[black small square] Prophylactic systemic antibiotics given pre-operatively.
[black small square] Topical antimicrobial agents (White et al 2001).
[black small square] Wound dressings (Bowler et al 1999).
Using dressings to control infection is a relatively novel aspect of wound management.
Barrier properties to some viruses and bacteria have been established; however,
dressings can help to contain the spread of pathogens through the formation of aerosols,
which disperse microorganisms into the air (Lawrence 1994), or by absorbing and
retaining bacteria (Bowler et al 1999). The use of dressings in the management of wound
colonisation and infection has been detailed in recently published articles (Kingsley 2001,
White et al 2001).
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The nurse's role in wound management
In the hospital setting, nurses form part of the multidisciplinary team and, as such, are
actively involved in all aspects of wound management. They are often responsible for
assessing patients' wounds, advising on dressing selection and dressing regimens, and for
referring patients to other services, such as tissue viability specialists and vascular clinics.
Different management models are used by health professionals working in wound care
units. For example, the hospital-based, nurse-managed model is the most common in the
US, while the physician-nurse management model is widely used in the UK (Bennett and
Moody 1995). In the community setting, nurses are the primary contact for patients with
tissue viability problems.
Nurses spend a considerable amount of their time on wound management and it is
essential that they encourage patients to become involved in their care and also that
patients are treated as active recipients of care. Good communication and active
participation in dressing selection is important as it increases patient autonomy and the
likelihood of using dressings that are considered 'ideal' from the patient's perspective,
which in turn enhances user satisfaction and concordance with treatment (Miller and
Collier 1996). To ensure the highest possible quality of care and to balance the needs of
the patient with the care they require, nurses need to be able to respond to changing
clinical practice which is based on current best evidence. These aspects of clinical
governance are illustrated in the two surgical wound case studies presented.
Clinical governance promotes working in partnership with patients, offering patients the
choice to decide what their needs are through empowerment. Ritualised practice, which
engenders a culture of control over the patient who is viewed as a passive recipient of
care, is no longer acceptable. Clinical governance relies on the practitioner's ability to
learn and unlearn faster and more effectively, to develop, understand and change
professional practice (Hamer 2000). Health professionals are required to keep their
practice up to date with lifelong learning and professional self-regulation to ensure that
acceptable standards of care are met. In doing so, nurses should continue to develop their
skills and self-regulate their practice, as not only will this help to ensure patients receive
the best treatment, but it will also promote competency in clinical practice.
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Case study 1
Terry, a previously fit, healthy 32-year-old male, was involved in a road accident and
sustained an intertrochanteric fracture to his right femur on March 7 2000. Terry was taken
to theatre on March 13 where he underwent internal fixation of his femur with a dynamic
hip screw (DHS). Over the next ten days he developed a wound infection with pus draining
from the suture line. A wound swab was taken and culture showed that the wound was
infected with MRSA. The suture line had healed by mid-May, but pain and reduced joint
mobility were evident. The infection did not resolve despite antibiotic therapy. On July 1,
Terry underwent an examination under anaesthetic which revealed a deep infection of the
bone around the DHS, with necrotic tissue. Wound exudate continued to yield positive
cultures for MRSA.
In July, further debridement and lavage of Terry's wound was undertaken. The DHS was
removed and proflavine packs were inserted (see White et al 2001). The suture line healed
again, but the MRSA infection persisted despite the administration of intravenous
teicoplanin (a glycopeptide antibiotic indicated for the treatment of gram-positive
infections). Terry was becoming increasingly anxious about his prolonged hospital
admission and his inability to get on with his life. He also expressed fear that the infection
in the bone would lead to limb amputation. He was discharged home into the care of
district nurses. They dressed his wound with a hydrogel and foam dressing. The wound
epithelialised again, but the infection persisted.
In November, further surgery was required and a wound abscess was debrided and
drained. However, MRSA was still a problem. In mid-November, a proflavine pack was reapplied with a plan to return to theatre three days later for examination and further
debridement, if necessary. At this stage the dressing was difficult and painful to remove
and, on removal, Terry commented that he could feel the relief of pressure at the wound
site. He was referred to the tissue viability nurse (TVN) who contacted the surgeon and
they discussed the use of dressings post-operatively. It was agreed that an alginate should
be used following surgery; this dressing would absorb excess exudate, act as a
haemostat, and would not require excessive packing, which would help to minimise pain at
dressing changes. This decision was discussed fully with Terry to reassure him that this
was the most suitable dressing to treat his wound and that it would not cause pain on
removal.
On removal of the alginate dressing at the first dressing change post-operatively, the leg
muscle was exposed and the femur was palpable (Fig. 1). There were signs of granulating
tissue, the exudate was haemoserous and there was no obvious odour from the wound.
Following discussion with Terry, and nursing and medical staff, it was decided to change
the dressing regimen to a combination of Mesalt and Alldress - two recently developed
wound products. Mesalt is an absorbant, sterile dressing impregnated with sodium
chloride, which creates a hypertonic wound environment that has an osmotic action. This
reduces interstitial oedema, thereby reducing compression on capillaries and improving
wound perfusion. The osmotic potential also helps to remove sloughy tissue and creates a
hostile environment for bacterial growth (Brown-Etris et al 1991).
Alldress is a secondary dressing that consists of a non-adherent contact layer, an
absorbent pad and adhesive cover. It is sealed with a film membrane that provides a
moist, warm, healing environment. The absorbent pad absorbs excess exudate and the
adhesive cover prevents strike through. Alldress prevents the need to use more expensive
foam dressings that are designed as primary dressings, particularly in situations where
dressings need to be changed frequently, for example, during autolytic debridement.
Terry's dressings were changed daily because of the presence of infection and large
amounts of exudate. The condition of the wound quickly improved. As the wound exudate
levels decrease, the osmotic effect of a dressing on a wound with insufficient exudate can
cause discomfort. Terry informed the TVN that he felt a 'drawing effect', and on discussion
it was decided to change the primary dressing to a hydrofibre dressing which would
promote patient comfort, maintain a moist warm environment and absorb the remaining
exudate (Fig. 2). It also has a gelling action, which enables the removal of any residual
slough by autolytic debridement. The dressing was left in situ for up to three days and
various secondary dressings were used to establish which dressing was the most
comfortable. Terry preferred the hydropolymer dressing because it was comfortable,
conformable, stayed in place and could be easily removed at dressing changes. When
Terry showered he raised the corner of the dressing and allowed the water to dissolve the
adhesive border. He found that this dressing was easier to manage and became much
more confident at managing the dressings. He had been informed of the signs and
symptoms of infection and was aware of what to look for on examining the wound.
Terry was eager to be actively involved in his treatment and was fully informed of the
rationale for any action taken. He was being nursed in a side-room because of the MRSA
infection and he often felt isolated and bored. He was, therefore, eager to do anything that
would hasten his discharge home and clear the underlying infection to allow healing to
take place. It was apparent that Terry could manage to care for his wound. However, he
was having a ten-week course of intravenous teicoplanin for the MRSA infection and
stopping this might have had disastrous results. The infectious diseases department in the
trust was contacted as they had a funded project allowing patients, who were suitable
candidates for the programme, to self-administer intravenous drugs with the support of a
nurse specialist. It was agreed that Terry was a suitable person to join the programme and
he subsequently had a peripherally inserted central catheter (PICC) sited for this purpose.
Terry was delighted when he was discharged home from hospital early in December 2000
and coped well with the dressing changes and antibiotic therapy. He intermittently returned
to the outpatient department of the infectious diseases unit where he could also access the
TVN service. His wound continued to improve slowly, but the cavity remained large.
Therefore, it was decided in January to use a hyaluronic acid dressing for two dressing
changes. The benefits of hyaluronic acid (hyaluronan) include encouraging cell motility and
promoting granulation (Ballard and Baxter 2000). Within seven days the wound had visibly
improved with a significant reduction in the volume of the cavity.
Terry continued caring for himself and on the last day of his ten-week course of antibiotics
he asked the TVN to examine his wound to see how much it had improved. By February
2001 the wound had completely re-epithelialised and there was no further recurrence of
MRSA infection.
Back to Top
Case study 2
Alison is a 40-year-old, independent and active woman. She was born with congenital
sacrococcygeal teratoma, which resulted in a colostomy at the age of three months. Since
then she has had many years of frequent bowel and urological problems. She had a
nephrectomy in 1995, and numerous bowel operations. Bowel obstructions that resulted
from adhesions were, whenever possible, managed conservatively. On July 27 2000, while
on holiday, she developed a bowel obstruction with evidence of necrosis. An ileostomy
was performed that included resection of a large segment of small bowel. The surgical
wound was left to heal by secondary intention. A painful track had formed at the base of
the wound that drained large volumes of pus (Fig. 3).
Alison was a lifelong 'expert' in dealing with her condition and was actively involved in her
care. She was referred to the TVN. On examination, the wound contained granulation
tissue with evidence of slough and large amounts of exudate. Pus continued to drain from
the track at the base of the wound. The choice of dressing was discussed with Alison and
a hydrogel dressing was introduced into the track. The track was too narrow to use
alginate dressings which might have 'plugged' it, preventing cleansing and drainage of
pus. Mesalt was placed on the remainder of the wound to aid removal of slough, reduce
oedema and provide a hostile environment for bacteria. Alldress (an absorbent multilayered dressing which is suitable for use on open wounds during all stages of healing)
was used as a secondary dressing. The wound was irrigated gently before the dressings
were applied.
Alison experienced many problems with her ileostomy that caused her a great deal of pain.
The stoma care sister played an essential role in her care. Because of the reduced size of
her small bowel and as she continued to feel nauseous and vomited following meals, the
involvement of the nutrition team was crucial to her care. Her poor nutritional state had
also adversely affected the wound-healing potential (Mulder et al 1998).
Despite these problems, the wound continued to heal. Alison, like Terry, informed the
nursing staff when she felt that the Mesalt was beginning to cause slight discomfort, and
this dressing was discontinued. The tracking area responded well to the hydrogel dressing:
the flow of pus stopped and granulation tissue was present in the cavity. The hydrogel was
discontinued (Figs. 4 and 5) and Alison chose the type of secondary dressing she
preferred, which was a polyurethane foam film dressing. She commented that this
dressing had many advantages in that it is comfortable to wear, easy to remove and
stayed in place. Alison's wound did not have any undermining and, therefore, was not
infected (Cutting and Harding 1994), so Tielle Plus was chosen for extra absorbency. This
swells in the wound on contact with exudate and keeps the nerve endings moist, thereby
minimising pain (Hampton 1999). Despite the large volume of wound exudate, Alison felt
that an additional primary dressing was not necessary.
Alison's wound continued to heal, but problems with her ileostomy prevented her from
being discharged from hospital. However, she was able to go out for short periods during
the day and spent weekends at home. The abdominal wound had completely healed by
December when she was discharged home.
The case studies have illustrated examples of holistic wound management of two patients
through close liaison between the hospital TVN, community nurses and the patients. They
show how consideration of the patient's needs and circumstances on assessment dictates
a wound management approach that includes patient involvement and dressing choice.
Common elements in both case studies are listed in Box 2.
Back to Top
Discussion
Post-operative wound management has progressed significantly in recent years. The
application of modern wound dressings and management approaches to surgical wounds
has the potential to revolutionise post-operative wound care. This involves reducing patient
pain and discomfort, enabling earlier patient discharge to the community, and planning
day-case surgery, where previously wound care necessitated hospital admission.
Important recommendations regarding patient benefits and the cost-effectiveness of
dressings (Moore and Foster 1998a and b, 2000) should be adopted in clinical practice.
Wound care in the UK is a nurse-led discipline and with recent advances in the
manufacture of dressings and increased choice, patients should no longer experience pain
during post-operative wound care. It is important that nurses working with surgical patients
are aware of current evidence and research on wound management and dressings, and
that they incorporate this information into wound care protocols. Clinical nurse specialists
in tissue viability should be consulted on wound management and dressing selection for
patients with complex or non-healing surgical wounds. The reluctance of some health
professionals to adopt new practices in wound care must be overcome, perhaps by nurses
becoming better informed and developing a more open dialogue with colleagues regarding
wound management recommendations. One possible solution would be for those who
dress wounds in theatre to have an opportunity to replace them on the ward, as 'first-hand'
experience might lead to improvements in practice. It is clear that improved quality of life
and quality of care could be achieved by working in partnership with patients
ARTICOLO 2
Infected Wound Management: Advanced Technologies,
Moisture-Retentive Dressings,
and Die-Hard Methods
Wound infection is a significant problem for the complicated, critically ill patient. A critical care
patient’s plan
of care can be challenging enough without complicating it with the additional comorbidity of a
wound infection.
Wound infection delays wound closure, disrupts wound tensile strength; increases hospital length of
stay and
costs; and escalates the patient’s risk of bacteremia, sepsis, multisystem organ failure, and death.1
The goal is to
reduce and eliminate the wound infection before it leads to such drastic consequences, especially in
the age of
antibiotic-resistant organisms. It is paramount to identify classic and not-so-obvious signs and
symptoms ofwound
infections, correctly collect a wound specimen, and assist in appropriate systemic and topical
wound management.
Techniques to prevent wound infection and reduce bioburden include nontoxic wound cleansing,
debridement
of necrotic tissue, proper antibiotic management, and appropriate use of moisture-retentive
dressings. Advanced
technologies in moisture-retentive dressings include sustained-release silver and cadexomer iodine
antimicrobial
dressings and negative-pressure wound therapy. Accurate wound assessment, knowledge of new
technologies,
and applying current wound care standards to clinical practice will assist the critical care nurse in
treating and
preventing wound infections. Key words: antimicrobial dressings, bioburden, colonization,
debridement, moisture
retentive dressings, wound cultures, wound infection, wound VAC
Sherry Campton-Johnston, RN,
MSN, CWOCN
Vice President Clinical Services
Total Wound Treatment Center
San Antonio, Texas
Joyce Wilson, RN, MSN, CWOCN
Clinical Nurse Specialist—Wound,
Ostomy, Continence
Wilford Hall Medical Center, United
States Air Force
Lackland Air Force Base, Texas
AWOUND INFECTION is a significant
problem for the complicated, critically
ill patient. A critical care patient’s plan of
care can be challenging enough without
complicating it with the additional comorbidity
of a wound infection. Stotts notes that
wound infection delays wound closure; disrupts
wound tensile strength; increases hospital
length of stay and cost; and increases
the patient’s risk of bacteremia, sepsis, multisystem
organ failure, and death.1 The goal is
to reduce and eliminate the wound infection
before it leads to such drastic consequences.
Utilizing universal precautions and/or isolation
measures when resistant organisms are
identified is the first line of defense to reduce
the spread of infection. Next, the critical
care nurse must be able to identify classic
and not-so-obvious signs and symptoms of
wound infections, correctly collect a wound
Crit Care Nurs Q 2001;24(2):64–77
°c 2001 Aspen Publishers, Inc.
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Infected Wound Management 65
specimen, and assist in appropriate systemic
and topical wound management. Knowing
the phases of wound healing is necessary
to interpret wound progress, which guides
treatment. Understanding the usage, pros,
and cons of the various dressing categories
will assist in deciding which type of dressing
is appropriate to control the condition of
each wound. Even with evolving therapies,
old “die-hard” treatments such as wet-to-dry
dressings are still being ordered. Learning
the science behind wound care will provide
the critical care nurse with the ammunition
to prescribe the best wound treatment to
facilitate the healing process. Ultimately,
all health care workers aspire to prevent
wound infections, but when infection is
present, meticulous wound care is essential
to limit its effect on the patient. The objective
of this article is to provide the critical
care nurse with an understanding of
issues relevant to wound infection and to
provide a tool to use in making a decision
based on up-to-date information about infected
and colonized wound management.
WOUND BASICS
Defining wound infection
Infection is a well-documented homeostatic
imbalance between the host and microorganism(
s) greater than 100,000 (105)
organisms/gram of tissue or the presence
of beta-hemolytic streptococci.1–8 Every
wound has microorganisms, called contaminants,
on its surface.Nowound or patient can
be absolutely germ free. If the organisms or
contaminants multiply, this colonization is
still not usually problematic. A wound can
improve and heal despite surface contaminants
and colonization, and if the wound tissue
is invaded with an organism, the host or
patient’s immune system helps fight against
organism invasion. If the patient or host cannot
overcome the invasive organism(s), then
a wound infection occurs.
Critically ill, diabetic, oncology, or transplantation
patients with a wound can be
at further risk for wound infection because
of their compromised immune systems’ inability
to fight against the organisms’ invasion
of the tissue. Lipsky has mentioned
the following physiologic events that place
the hyperglycemic diabetic patient at risk:
impairment of polymorphonuclear leukocyte
functions, including abnormal phagocytosis;
impairment of leukocyte function;
and reduced cellular immune responses and
monocyte function.4 If the wound is located
on the foot, diabetic patients may
be further at risk because of foot deformities;
micro- or macrovascular disease, which
causes tissue hypoxia and ischemia; neuropathy,
which causes an inability to feel ongoing
trauma; and remarkable retinopathy,
which interferes with their ability to see foot
complications.
Phases of wound healing
If the host or patient with the wound
can overcome the organism’s invasion of
the tissue, the wound should heal, but only
if healing proceeds in an orderly fashion
through the wound healing cascade, or the
four phases ofwound healing. The first phase
is the coagulation or hemostasis phase, in
which fibrin and platelet aggregation occurs
after trauma is induced. Clinically, one
should see blood clotting shortly after trauma
or “wounding.”
The second phase of wound healing is
the inflammation phase, which takes place
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after coagulation and takes up to three or
four days. Some sources in the literature
combine the coagulation or hemostasis
phase and inflammation. Platelets, neutrophils,
lymphocytes, macrophages, and
epithelial cells are some of the key cellular
components in this phase. Clinically, one
should see periwound edema, erythema,
and perhaps drainage; the patient may
experience pain. These clinical signs and
symptoms may be mistaken for infection;
thus a thorough history of when the wounding
occurred is a very significant factor.
The third phase ofwound healing is proliferation
or granulation and occurs from day
4 to 21. If the wound is large, granulation
may take more than 21 days; however, after
21 days, wound healing is also at risk of
becoming stalled. The resumption of healing
might only occur if the wound is retraumatized
to reinitiate the healing cascade.
Cellularly, macrophages and fibroblasts are
proliferating and angiogenesis is occurring.
Clinically, there should be resolution of the
periwound erythema, heat, and edema; the
wound bed should be beefy red and becoming
smaller until full closure.
The fourth and final phase of the woundhealing
cascade is maturation or remodeling,
which lasts between 21 days and 2 years.
Fibroblasts should be synthesizing the collagen
and elastin. By this time, the scar
should be becoming stronger, shrinking, and
appearing less red. It takes many months
to up to nearly two years for a scar to
meet its maximal tensile strength, which is
about 75% of its original tissue strength.
Wound types
If the wound does not follow the phases in
this order, the wound may become stalled,
recalcitrant, or chronic. Several conditions
can impede thewound-healing cascade: malnutrition,
immunosuppression, and infection.
Wounds that are hypoxic or dried-out
or repeatedly become traumatized or reinjured
without correction of the problem also
take longer to heal. Examples of retraumatization
without correction of the problem
are diabetic patients who continue to walk
on their plantar surface ulcer and pressure
ulcer patients who continue to lie on their
wound. Reinjury continues to damage the already
traumatized wound. The critical care
unit staff will encounter a variety of acute
wounds, from traumatic minor skin tears to
road burns from motor vehicle collisions to
de-gloving injuries. Chronicwounds may include
pressure ulcers, lower leg arterial or
venous stasis ulcers, or open complicated
surgical wounds requiring closure by secondary
intention. It is important to assess and
identify a wound type to intervene appropriately.
In a study of 61 acute wounds and 45
chronic wounds with anaerobic and aerobic
isolates, anaerobic bacteria often constituted
a significantly greater proportion of the total
microbial populations.9 Thus, this information
may be helpful whenwound cultures are
pending and confirmation with a Gram stain
is needed.
Most surgicalwounds are considered acute
unless they exceed the time frame mentioned
in the phases of wound healing. According
to the Centers for Disease Control and
Prevention (CDC), a superficial surgical site
infection (SSI) involves only the skin (epidermis
or dermis) and subcutaneous tissue
and occurs within 30 days after the procedure.
An SSI must also involve at least one
of the following components: purulent incisional
drainage; organisms isolated from
an aseptically obtained incisional fluid or
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tissue culture; diagnosis by the surgeon or
attending physician; or one of the listed
signs or symptoms: pain or tenderness, localized
swelling, and redness or heat.10 The
mainstay treatment for a superficial SSI is
systemic specific antibiotics and moistureretentive
dressings (MRDs). (See Table 1 for
examples.)
A deep SSI is similar to a superficial SSI,
except it penetrates the muscle or fascia layers.
Also, the infection may surface up to
one year later if an implant is in place and
the deep tissues are infected. Additionally,
deep SSI involves more in-depth signs or
symptoms, such as an abscess or infection
identified by a return to the operating room,
histopathologic study, or radiologic examination
and a fever of at least 38±C.10 The
treatment is similar to that for superficial SSI
but may include an additional procedure of
incision and drainage or implant extraction.
The CDC defined the most-severe surgical
infection as organ or space SSI that involves
organs or spaces opened or manipulated
during surgery, beneath the incision. It
has the same time parameters as deep SSI
and involves purulent drainage, except from
a drain into the organ/space. In addition, organ
or space fluid or tissue may be cultured,
or have an abscess formation diagnosed by
the surgeon. An organ or space SSI does not
require the patient to exhibit signs and symptoms
of fever, pain, etc. for the diagnosis.10
The treatment is systemic specific antibiotics
and MRDs, and may include an additional
procedure of incision and drainage or implant
extraction.
Clinical signs and symptoms of a chronic
or recalcitrant wound, such as a change in
wound drainage, change in odor, a sudden
high glucose level in a diabetic patient, poor
quality granulation tissue, periwound redness
or warmth, or pain or tenderness, may
be less obvious.1 Poor quality granulation
tissue may be red or pink and have a softer,
gelatinous, friable texture. Equally important,
if a wound is not healing or shrinking,
perhaps a silent infection is in progress.
Occasionally a chemotherapy patient or one
who is taking steroids or immunosuppressive
medications may have a poor defensive
response to infection and may not elicit the
typical signs of infection.
Wound culture standards
In addition to deciphering clinical signs
and symptoms and complicated patient histories,
accurate diagnostic interpretations
and correct wound culture collection are important
in identifying a truewound infection.
This is particularly important today in the
age of cost containment, antibiotic-resistant
infections, and rising health care costs.
Tissue or punch biopsies, rather than
surface swab cultures, are the gold standard
of quantitative wound culture techniques.
1;2;4;11 Tissue culture is the most specific
method available because it assesses the
organisms that have invaded the tissue, not
just those on the surface of the wound. Only
occasionally does a surface swab culture of
a colonized wound capture the actual organism
that has caused a tissue infection.1
In a study of 51 patients and 72 pressure
ulcers, swab specimens reflected only surface
colonization and needle aspiration underestimated
bacterial isolates.11 Although
tissue biopsy is the most sensitive and specific
quantitative test to assess wound infection,
it does have its disadvantages. For
example, only licensed providers or credentialed
advance practice nurses can legally obtain
tissuewound samples. Furthermore, it is
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Table 1. Moisture-Retentive Dressing Categories: Advantages, Disadvantages, and Indications
Dressing Advantages Disadvantages Indications
Antimicrobial Slow release of iodine or silver for continuous Potential for iodine toxicity in large
Infected or highly colonized
dressings reduction of bacteria without toxicity. wounds. wounds. Necrotic wound surfaces.
Transparent Retains moisture. Supports autolytic debridement. Should not be used on fragile skin
Partial thickness wounds. Stage I
film dressings Semi-occlusive. Adhesive. Acts like second skin because of adhesiveness.
Nonabsorptive; and II pressure ulcers. Use on
over friction areas, Bacterial barrier. Clear traps fluid under dressing, causing dry wounds for
autolytic
visibility of wound. Less frequent dressing maceration of surrounding skin. debridement.
changes (every 3 days versus 3 times a day) is
dressing and labor cost savings.
Hydrogels: Hydrates tissue. Aids autolytic debridement. Macerates surrounding skin. Shifts position
Partial and shallow fullgel
or sheet Sheet form absorbs small amount of because is nonadherent and must be thickness wounds.
Radiation
dressing exudate. Nonadhesive. Cool and soothing wrapped in place. Edges will dehydrate sites.
Painful wounds. Stage II–III
when applied. Clear visibility of wound. if exposed to air. Does not work well pressure ulcers.
Venous stasis
Change every 3 days. in sacral cleft. ulcers.
Copolymer Absorbs exudate and “cleans” slough from wound. Must be irrigated out of the wound.
May Cavity wounds with or without
starches Adapts to any irregular shape of the wound. macerate periwound skin. Requires a necrosis.
Exudating wounds.
Ideal for chronic cavity wounds. Change daily. cover dressing.
Calcium Absorbs 20 to 30 times its weight in exudate. Can macerate the surrounding skin.
Exudating wounds. Infected
alginates Nonadhesive. Molds to the wound bed. May dehydrate small wound surfaces. wounds.
Incisions. Cavities.
Can be used in infected wounds. Provides a Requires a cover dressing. Should not Pressure ulcers.
Venous stasis
gel that supports autolytic debridement. use in necrotic wounds (more than ulcers.
Use in wounds that are debrided to 75% red. 25% necrotic).
Rope for packing tracts. Change daily or
according to strike through to cover dressing
(more or less often). Change according to
dressing hydration (daily or longer).
Polyurethane Nonadhesive Absorbs and wicks away drainage May dehydrate small wound areas.
Shallow exudating wounds. Reduction
foams from the wound. Effective under compression Requires tape or wrap to hold in place. of
periwound maceration.
dressings. Change every 3–7 days. Stasis ulcers. Cover dressings.
Hydrocolloid: Adhesive and can be cut to fit difficult dressing Should not be used on fragile skin.
Ineffective Partial and full thickness moist
thick and thin areas. Interacts with wound fluid to form if the wound bed is dry. Add hydration
when wounds. Used for autolytic
versions protective gel. Insulates the wound. used for autolysis. Disrupts new tissue if debridement.
Stage II and
Occlusive and enhances angiogenesis. removed too frequently. Should not be used shallow Stage III
pressure
Supports autolytic debridement. Protects from in diabetic feet when anaerobes are ulcers that are
not infected.
secondary infection. Change every 3–7 days suspected because of occlusiveness. Not Stasis ulcers.
depending on the amount of drainage. effective on dry wounds.
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more costly and painful to the patient and not
all facilities have tissue-culturing capabilities.
That being said, which is more costly,
mistreating a patient’s wound infection and
thereby increasing the chance of medication
resistance or allergies, or performing a
more accurate, more costly microbiological
test?
Conflicting sources in literature state that
wound swab cultures are comparable to tissue
culture swabs or wound aspiration. For
example, one study of 10 biopsy specimens
from five patients with critical burns demonstrated
similar results of surface swabs and
punch biopsies;6 however, problems in the
study were that eschar tissue was cultured,
the tissue wounds were cleansed with
alcohol—which can cause false negative
specimens—and the sample size was small.
Another study compared fine-needle aspiration
biopsy and swab cultures of 45 patients
with many types of wounds; the results were
that aspiration biopsies were 100% sensitive
and swab cultures were 90% sensitive.12
In another study comparing swab and tissue
cultures, itwas noted that the swab technique
is valid only for open wounds not covered by
necrotic tissue.7
The correct procedure for wound-culture
sampling is for a viable tissue specimen to
be collected after cleansing the wound with
normal saline. This will prevent collecting
surface contaminants and will collect the
live culprit invading the live tissue. Normal
saline is the optimal wound culture preparation
because many other preparations kill
organisms. Many clinicians falsely assume
that the greener or more unappealing the
specimen appearance, the better the specimen.
Also, clinicians are fearful that cleansing
with saline will wash away the bacteria
causing the wound. On the contrary,
irrigating a wound with normal saline cleans
the surface contaminants away; if the tissue
is infected, it will still be apparent on
the specimen. A clinician can further assist
accurate wound sampling by coordinating
prompt transport of the specimen to the laboratory
for processing.Wound-culture specimens
should include a Gram stain and aerobic
and anaerobic cultures. The Gram stain
can be read in 20 minutes and the preliminary
culture results should be ready in
24 hours.
Swab culture technique
If a swab culture is collected, be sure to
cleanse the wound with sterile saline and
to culture only viable tissue. Twirl the end
of the sterile-tipped applicator stick on one
square centimeter area of the open wound
for five seconds. Insert the swab into the culturette
tube and crush the media to preserve
the collected specimen. Transport immediately
to the laboratory for processing.1;2;5
Aspiration technique
Be sure to cleanse the wound with sterile
saline; again culture only viable tissue. Disinfect
the intact skin that is adjacent to the
wound with an antiseptic (alcohol or povidone
iodine) and allow the skin to air dry
for one minute. Place 0.5 cc of air in a 10-cc
syringe and insert the needle into the skin adjacent
to the wound. Withdraw the plunger
to achieve suction and move the needle back
and forth at different angles. Remove the
needle carefully from the tissue, ensuring
that none of the collected drainage is allowed
to return to the tissue. Transport the syringe
specimen immediately to the laboratory for
processing.1;2
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70 CRITICAL CARE NURSING QUARTERLY/AUGUST 2001
TREATMENT OF INFECTED
WOUNDS: REDUCING THE
BIOBURDEN
The overall goal of treatment of infected
acute and chronic wounds is to reduce the
bacterial load in the wound to a level at
which the wound healing process can go
forward. Wound infections are detrimental
to wound healing and must be eliminated
before granulation tissue will proliferate.
At the same time, treatment should
cause no harm to the already traumatized tissue,
which would further delay healing. Balancing
treatment to eradicate bacteria while
maintaining the integrity of healthy wound
tissue is a dilemma in wound care management
today. The three methods of eliminating
the source of infection in a wound are
debridement, wound cleansing, and topical
antibiotic application.3
Debridement of devitalized tissue
Infected wounds with a bacterial load of
>105 will often contain devitalized tissue
and/or excessive exudate and may undermine
or tunnel. Debridement of the necrotic
tissue and reduction of exudate are essential
in decreasing the bioburden. The four
most common methods of debridement used
in the intensive care unit are (1) a surgical
procedure for sharp debridement of dead tissue,
(2) mechanical debridement with dressings
or irrigation, (3) enzymatic debridement
with chemical debriding agents, or (4) autolysis,
which uses the body’s own wound fluid
to destroy debris under MRDs.5;13 The first
two methods are nonselective, meaning that
healthy tissue may also be debrided. Surgical
debridement is the quickestway to rid the
wound of devitalized tissue. This can be advantageous,
because it can reduce the duration
of antibiotic use. Nonselective, sharp debridement
of a stalled, chronic wound may,
in fact, convert it to an acute wound and reinitiate
inflammation and the wound healing
cascade.3 Sharp debridement may be selective
if only necrotic tissue is removed. Disadvantages
are that nonselective surgical resection
removes healthy tissue, making the
wound larger. In the critical care arena, a patient’s
tenuous medical condition, such as
caused by a blood clotting disorder or unstable
hemodynamic status, may not allow a
surgical intervention.
The second nonselective debridement process
and the most commonly used method
is mechanical debridement. For example, a
wet-to-dry dressing using a coarse, largepore
gauze allows the dead tissue to dry on
the gauze and then be pulled out of thewound
with the dressing.13 This method may also
tear healthy granulation tissue with dressing
removal and is not without pain. In addition,
it further traumatizes the tissue by re-injuring
it two to three times a day and increases the
healing time.
Two tissue-specific debridement processes
include enzymatic and autolytic debridement.
The newest generation of enzymes
(Accuzyme by Health Point Inc. and Santyl
by Smith and Nephew) breaks down denatured
collagen and nonviable protein in
the wound debris without disrupting healthy
tissue.13 This enzymatic process is quite
slow if the debris is thick; however, a multistate
study comparing an enzymatic agent
with an aqueous wound gel (a wound hydrator)
demonstrated that the wound gel was
more efficacious and less expensive than the
enzyme.14 In contrast to the latest generation
of enzymatic debriders, previous enzymatic
products that are now off the market were
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nonselective and digested necrotic and viable
tissue.
Autolysis is the second selective debridement
process of digesting wound debris
by using the body’s own defense mechanism.
After wounding, the inflammatory
phase of healing puts into motion neutrophils
and lymphocytes that travel to the injured
site, phagocytize bacteria, and release proteolytic
enzymes that digest debris. Neutrophils
also release mediators that stimulate
cellular growth.15 Autolytic (meaning selfkilling)
debridement works over time with
the use of MRDs. These dressings hold the
body’s natural defense fluid over the wound
for several days, allowing healing to take
place undisturbed. The process decreases patient
discomfort, reduces the potential for
product sensitivity, and is less labor intensive
for nurses. On the other hand, autolytic debridement
requires more time for complete
debridement, particularly if the necrosis is
thick.
Debridement of a large necrotic cavity
wound covered by eschar may require several
methods of debridement to facilitate
healing. An MRD and a wound gel or enzyme
could be used to soften and degrade
the eschar. Thiswould facilitate sharpwound
“core” debridement at the bedside. The remaining
slough could be removed mechanically
with pulsatile irrigation and/or gauze
dressings until a healthy wound bed is exposed.
Then MRD would protect, insulate,
and nurture the granulation tissue until the
wound defect is filled.
Debridement is usually necessary to facilitate
wound healing; however, there are exceptions
to this rule. Patients with ischemic
ulcers are not debrided; debriding these ulcers
without restoring circulatory supply will
worsen their condition and occasionally require
amputation. Debridement is not required
for stable heel ulcers that exhibit a
dry eschar and no edema, erythema, fluctuance,
or drainage; however, daily assessment
should be performed because debridement
would be needed if any signs of infection
were to surface.8
Wound cleansing
Wound cleansing is the next step in reducing
a wound’s bioburden. The “do no
harm” issue is particularly pertinent in this
category. Wounds can be cleansed by mechanical
force or by solutions; at all times,
universal precautions (now known as standard
precautions) should be used during
wound care. Wound cleansing is effective
when the proper nontoxic solution and
the appropriate mechanical force are combined
to remove necrotic tissue, exudate,
metabolic wastes, and dressing residue from
the wound’s surface.13 Isotonic saline (0.9%
NaCl) is the most physiologic solution and
the safest to use and will cleanse most contaminated
wounds. If wounds are infected
or highly contaminated with debris, a commercial
nonionic cleanser with a surfactant
(a material that lowers the surface tension
between the tissue and the clinging material)
can be used to facilitate dislodgment.16
Several acceptable cleansers are Sur Clens
(ConvaTec), Biolex (Bard), Saf Clens (ConvaTec),
and CaraKlenz (Carrington).17
The Treatment of Pressure Ulcers, written
by the Agency for Healthcare Policy and Research
(currently known as the Agency for
Healthcare Research and Quality) in 1994
and revised in 1997, remains today the standard
by which care providers are legally
held responsible.18 After an extensive review
of the literature, this panel concluded that
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solutions such as povidone iodine, Dakin’s,
hydrogen peroxide, and acetic acid should
not be used in granulating wounds because
they are all cytotoxic to fibroblasts, and thus
disrupt the wound healing cascade.16;17;19
Povidone iodine, for example, destroys the
red and white blood cells and can actually
potentiate infection. Robson compared three
treatments to reduce the bacterial burden
from >105 to <105 in a population of infected
pressure ulcer patients. One group
was treated with povidone iodine, another
with normal saline wet-to-dry dressings, and
the third with silver sulfadiazine cream.
Povidone iodine had the lowest success rate
(63.6% in reducing the bacterial concentration
below 105), wet-to-dry was successful
78.6% of the time, and silver sulfadiazine
was successful 100% of the time.20 The controversial
use of the “die-hard” wound disinfecting
solutions is a difficult pattern to
break. Research over the past 20 years continues
to affirm that providone, Dakin’s, hydrogen
peroxide, and acetic acid solutions
are detrimental to wound healing. Whether a
diluted form of these solutions can be used in
completely necrotic wounds without having
a negative effect onwound healing outcomes
is yet to be researched.18;21
The mechanical force of wound irrigation
delivered to the wound bed can effectively
reduce the adherence of debris. Although
whirlpool therapy in the past has been used
to clean necrotic debris from wounds, questions
arise as to its efficacy in light of increasingly
resistant organisms and infection
control issues. This treatment is generally
not indicated for critically ill patients because
of logistics and compounding medical
status. Wound irrigation therapy at the
bedside can replace whirlpool sessions. This
irrigation involves the controlled force of a
fluid directed into the wound that is greater
than the force holding the material to the
wound bed. The force is measured in pounds
per square inch (psi) and ranges between
4 psi and 25 psi. Strong pressure irrigation
can be accomplished with a 35-cc syringe
and a 19-gauge needle hub or an angiocath
that delivers approximately 15 psi to
the wound’s surface.16 The process is easy
and effective because it softens, loosens,
and removes devitalized tissue and bacteria,
thus reducing contaminants. Because the
high pressure irrigation may cause the splattering
of wound fluid or blood, the Occupational
Safety and Health Administration
requires the use of a gown, gloves, and a
face mask with protective eye gear during the
procedure.22 There are several commercial
irrigation systems on the market to facilitate
this bedside procedure, for example, a syringe
mechanism (Irrijet by Ackrad Laboratories)
and battery-operated pulsating handheld
devices (Stryker and Davol). Some
devices have the added advantage of suction
to remove the irrigant and debris from the
wound site. If pressures over 25 psi are used,
mechanical trauma to the wound surface can
occur, forcing bacteria into these injured tissues
and increasing infection potential to the
tissue.23 Remember to Do No Harm. As the
wound condition improves and granulation
tissue begins to fill the wound, the force
of irrigation fluid should be decreased. If
the wound is clear of debris, forceful irrigation
(debridement) should be discontinued.
Granulating wounds should be flushed with
normal saline at the low pressure of 8 psi.
Wounds that showno progress for two to four
weeks after debridement and proper wound
care should be considered for underlying tissue
infection. Atwo-week trial of topical antibiotic
therapy can be initiated.24
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Topical antibiotics
Wounds that are considered infected by tissue
culture confirmation and contain bacterial
colonies >105 or progressing cellulitis,
signs and symptoms of sepsis, or osteomyelitis
require systemic antibiotic treatment specific
to the organisms identified. Topical antibiotic
treatment can aid in reducing the
local bacterial count to <105, thus improving
the environment for healing.25 Antibiotics,
unlike antiseptic solutions, which
damage all cells they encounter, are selective
in killing the bacteria without damaging
healthy tissue. Silver sulfadiazine (1%)
cream, bacitracin zinc, polymyxin B, and
bacitracin zinc C neomycin are effective
against Gram-positive and Gram-negative
organisms. Anaerobes are best treated
with metronidazole gel 0.75%. Methicillinresistant
Staphylococcus aureus responds to
mupirocin 2%.25 Be aware when using silver
sulfadiazine that a pseudoeschar forms
over the wound surface as it reacts with
wound moisture; this must be removed before
more cream is applied or the wound will
stop progressing.26
WOUND ASSESSMENT DRIVES
DRESSING CHOICES
Wound dressing options are numerous and
are selected according to the condition of
the wound. Wound assessment and documentation
are critical in choosing an appropriate
dressing and in changing that choice
as the wound environment evolves. Contrary
to common practice, the wet-to-dry
gauze is not a “one-size-fits-all” dressing for
open wounds today. Selection depends on
the needs of the wound and the condition
of the patient. One easy assessment tool to
utilize is the red-yellow-black color system
to evaluate the wound’s requirements and
direct the treatment plan.27 Wounds with a
red surface are ready to heal and require
the maintenance of a clean, protected, moist
wound environment.Yellowwounds contain
exudate and/or fibrinous slough and direct
the treatment toward debridement, cleansing,
and absorption to remove the bacterial
colonization that replicates in this devitalized
environment. If the wound surface is
covered or contains thick, leather-like, black
or brown-gray tissue, it is indicative of dried
collagen called eschar. This necrotic tissue
hides the wound’s depth and necessitates debridement.
Next, consider the size, depth,
and location of the wound, the amount of
exudate, and the condition of the surrounding
skin margins. Does the wound contain
tracts or areas of undermining?With this information
established, dressing selection can
be addressed.
Gauze is available in all shapes and sizes
and is inexpensive per dressing change compared
with many other dressings; however, it
absorbs only its own weight in exudate and
does not always conform easily to wound
locations such as elbows, heels, sacrum, or
knees. Gauze is bulky and requires tape or
wraps to secure. It must be changed two
to three times per day, which adds significantly
to the cost of the dressing. If allowed
to dry in a granulating wound, gauze
will dehydrate the healthy tissue and debride
it. The new generation of MRDs has
numerous positive effects on wound healing.
An MRD enhances re-epithelialization,
promotes granulation tissue formation, provides
continuous thermal insulation of the
wound bed (since the dressing is changed
every one to three days versus three times a
day), protects thewound from trauma during
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dressing removal, aids in autolytic degradation
of necrotic tissue, protects the wound
from infections, and reduces pain for the
client.28
NEW DRESSING TECHNOLOGY
Advanced technologies incorporated into
dressings have added new dimensions to
infected wound therapy. Cadexomer iodine
(CI) (Iodoform and Iodosorb by HealthPoint) dressings contain a 0.9% concentration
of iodine, which is slowly released into
the wound as the wound fluid is absorbed
into the latticework of the dressing. This
serves as anMRDwhile providing an antimicrobial
environment as it absorbs exudate.29
Sundberg reports that in 15 out of 19 studies
comparing CI with various dressings, CI promoted
wound healing better than the other
dressings. The paste form or sheet dressing
is effective in infected wounds and those
containing slough. With the fear of using
iodine solutions as outlined above, the current
research-based evidence should make us
look again at this old product in a “newwrapper.”
Lowconcentrations in a regulated slowiodinerelease mechanism have been shown
to promote, rather than delay, healing.
Another new antimicrobial dressing utilizing
silver ions is effective in the fight
against antibiotic-resistant organisms, such
as Staphylococcus, Pseudomonas, Enterococcus,
and Candidiasis. Two such products
available on the market are Arglaes
(Medline) and Acticoat (Westain Biomedical).
One of these slow-release silver dressings,
used under compression wraps for
seven days in venous stasis ulcers, demonstrated
a more effective antimicrobial action
than silver sulfadiazine, 56% versus 9%
respectively.30 There is potential use for both
of these new technological dressings in our
antibiotic-resistant environment.
MOISTURE-RETENTIVE
DRESSINGS
The characteristics of sevenMRDdressing
categories (antimicrobial, transparent films,
hydrogels, absorptive copolymer starches,
calcium alginates, polyurethane foams, and
hydrocolloids dressings) will be discussed.
This list is not inclusive of every available
dressing type but represents the most
common and readily available products to
providers. Table 1 describes the pros, cons,
and usage of these MRD products.
A misconception regarding infection and
MRDmust be addressed first. Providers raise
the concern that these dressings will encourage
bacterial proliferation and invasion into
the tissues, causing infection under the longwearing
dressings; however, this has proven
false. For example, in a randomized, controlled
clinical study of skin graft donor
sites, the incidence of infection was greater
in those dressed with impregnated gauze
than those treated with an occlusive hydrocolloid.
Dry gauze dressing changes
were also found to disperse more bacteria
into the air than with a moist dressing
change.31 Hydrocolloids have been found to
prevent the spread of methicillin-resistant
Staphylococcus aureus in chronic venous
stasis ulcers in hospitalized patients.32
Calcium alginate dressings absorb 20 to
30 times their weight in exudate and are useful
for highly moist wounds. There are flat
dressings and ropes for packing; they are
placed on or into the wound dry. As the
dressing absorbs the exudate, it converts
partially or totally to a gel. The dressing’s
sodium/calcium balance controls the
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amount of gel or residual dressing left in
the wound.33 It is an excellent dressing for
packing dehiscent surgical wounds because
it promotes granulation and is a comfortable
dressing that is tolerated well by patients.
Also very absorbent are the polyurethane
foams. In a randomized, controlled trial comparing
calcium alginates with foam dressings
in venous stasis ulcers with moderatetohigh exudate, it was determined that there
was no significant difference in their ability
to absorb exudate; however, the foam stuck
to the wound less often and had less odor
and less strike-through of the exudate to the
outside.34
Because foams have a wicking action,
more drainage is drawn into the dressing,
which can be useful when maceration to
the periwound skin has occurred from other
dressings. Foams work well under compression
dressings that are left in place for seven
days.
Amorphous hydrogels help hydrate a
wound and can also act as a wound filler.
Hydrogel sheets must be in contact with the
wound and are used for surface lesions—red,
yellow, or black. They are moist, contribute
to autolytic debridement of yellow and black
wounds, and support healing of a red-based
wound. Because they are nonadhesive, they
are held in place with a Kerlix wrap and thus
are an excellent choice for treating patients
with fragile skin. Hydrocolloids remain the
best choice for sacral area wounds because
of their adherence and their occlusion to contaminants
(stool and urine).32 Frequency of
required dressing changes is a consideration
in using hydrocolloids. Repeated removal
of this adhesive dressing may contribute to
stripping the newly healed tissue so it is designed
to remain in place for several days
to leave the wound undisturbed. Securing
the edges of the dressing with paper tape
or transparent film strips will prevent rolling
edges and premature removal.
Dressing decisions will change according
to the wound’s situation. Dry wounds need
hydrating dressings. When the wound becomes
moist, an absorption or debridement
dressing is required. After slough and exudate
have resolved, thewound will need to be
maintained with a moist dressing to promote
granulation and skin resurfacing. Canwound
care be successful if you do not have all of
the above dressing categories? The answer
is yes. There are a variety of gauze dressings
available to accomplish the above objectives
and effectively manage wounds; however,
the process will be more labor intensive
for the nurse, more uncomfortable for the
patient, and more costly because of lengthened
healing time. Gauze can be an MRD if
not allowed to dry between dressing changes.
Drainage strike-through must be monitored,
however, for fear of an ascending infection
through the moisture. More frequent dressing
changes also make home care coverage
harder to arrange.
VACUUM-ASSISTED
WOUND CLOSURE
Over the past few years, a new dressing
modality has gained merit and is being used
for an increasing variety ofwounds.Vacuum
Assisted Closure (VAC) (Kinetic Concepts
Inc.) has produced exceptional outcomes in
faster healing times of complicated wounds,
such as pressure ulcers, dehiscent surgical
wounds, and diabetic foot ulcerations. VAC
provides subatmospheric or negative pressure
to the wound bed at 125 mm/Hg continuously
for 48 hours, and then changes to
intermittent pulsating suction. The dressing
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in contact with the wound’s surface is a
polyurethane foam, which is cut to fit the
shape and depth of the wound. The dressing
and suction tubing are sealed to the skin with
a transparent film dressing. The fluid drawn
from the wound is contained in a canister
attached to the pump. Debris and edema in
and around the wound tissue are removed
by the suction, allowing blood vessels to expand
and better nourish the wound site.30;34
In a prospective, randomized trial of theVAC
versus saline wet-to-moist dressings in large
chronic wounds that had failed other treatments,
the patients treated with the VAC experienced
a 6%change inwound depth compared
with a 20% change in the saline gauze
group.35 VAC should especially be considered
forwound closure in patients with deep,
nonhealing, chronic wounds. Because this
wound therapy is portable, it can be used
in the home care setting, expediting hospital
discharge. Plastic, orthopaedic, and trauma
surgeons and internal medicine physicians
are prescribing this technology for numerous
types of wounds.
CONCLUSION
Wound infection occurs when the host’s
tissue defenses cannot overcome the invasion
of microorganisms. This delays the
healing process and jeopardizes the critical
care patient’s physiological status. Not all
wounds are infected, despite the presence
of necrotic tissue and exudate, but most
wounds are colonized. When there are local
or systemic signs of infection, culturing
the wound by punch biopsy is the most accurate
method of determining actual tissue
invasion by a microorganism. If an institution
has tissue culturing capability and a
skilled provider to collect the specimen, this
method is optimal. Only after accurate specimen
collection and interpretation should
a definitive antibiotic therapy be initiated,
especially as antibiotic-resistant organism
cases increase. Reducing the bacterial burden
in the wound through debridement,
wound cleansing, and topical antimicrobial
treatment helps to improve patients’ ability
to defend themselves. The use of diehard
antiseptics, which are cytotoxic, has no
proven efficacy in wound care and should
be avoided. Nontoxic cleansing methods and
topical antibiotics can play an important role
in minimizing microbial overgrowth. A variety
of new generation dressings is available
to accommodatewounds’ needs according
to their changing condition along the
continuum to healing. New therapies, such
as silver and iodine sustained-release dressings,
may have a huge impact, particularly in
treating resistant organisms. The negativepressure
wound VAC system is making a dramatic difference
in improved outcomes for management of large,
problematic wounds. Wound care decisions require
astute clinical assessment and decision making.
ARTICOLO 3
Management of Wound Complications From Cesarean Delivery
Sarsam, Sue Ellen CNM*; Elliott, John P.†; Lam, Garrett K. MD‡
Author Information
*Nurse Practitioner, Phoenix Perinatal Associates, an Affiliate of Obstetrix Medical Group of
Phoenix, PC, Phoenix, Arizona; †Associate Director of Perinatal Services, Phoenix Perinatal
Associates, an Affiliate of Obstetrix Medical Group of Phoenix, PC, Phoenix, Arizona and Clinical
Professor, University of Arizona School of Medicine, Tucson, Arizona; and ‡Associate Director of
Perinatal Services, Phoenix Perinatal Associates, an Affiliate of Obstetrix Medical Group of
Phoenix, PC, Phoenix, Arizona and Clinical Assistant Professor, University of Arizona School of
Medicine, Tucson, Arizona
Chief Editor’s Note: This article is the 19th of 36 that will be published in 2005 for which a total of
up to 36 Catgory 1 CME credits can be earned. Instructions for how credits can be earned appear on
the last page of the Table of Contents. This CME activity is supported by an unrestricted
educational grant from Procter & Gamble.
The authors have disclosed that they have no financial relationships with or interests in any
commercial companies pertaining to this educational activity.
Wolters Kluwer Health has identified and resolved all faculty conflicts of interest regarding this
educational activity.
Reprint requests to: Garrett K. Lam, MD, Phoenix Perinatal Associates, an affiliate of Obstetric
Medical Group of Phoenix, PC, 1331 N. 7th Street, Suite 275, Phoenix, AZ 85006. E-mail:
[email protected].
Abstract
Multiple factors account for the increasing number of cesarean delivery wound
complications in the United States; among them are an increase in cesarean delivery and
an increase in the number of overweight and obese patients. This article reviews the
pathophysiology of acute wound healing. Risk factors for cesarean delivery wound
complications are identified and described. Clinical practices that can reduce the risk of
developing wound complications, including Centers for Disease Control and Prevention
guidelines, are considered. Treatment guidelines to accelerate wound healing such as
secondary closure and negative pressure wound therapy in disrupted wounds are
proposed. Older guidelines for management of wounds using secondary intention are
critiqued. Historical methods of wound care such as the practice of using certain cleansers
and the practice of wet to dry dressings are outdated. Modern wound healing products are
described.
Target Audience: Obstetricians & Gynecologists, Family Physicians
Learning Objectives: After completion of this article, the reader should be able to describe
the effects of obesity on cesarean delivery wound healing, to improve methods of wound
healing in the obese patient, and to explain why wet to dry dressing changes are not
effective wound management.
Wound complications from cesarean delivery are a significant emotional and economic
burden in obstetric care. The postpartum period is a challenging time for women, as a
result of stressors such as fluctuations in hormone levels, caring for a newborn baby, and
recovery from the actual delivery process. A postoperative wound complication further
intensifies an already difficult period of adjustment. The economic burden is difficult to
quantify but is likely significant.
A recent review of obstetric practice in the United States revealed that cesarean delivery
accounted for 26.1% of all births in 2002 (1). Concurrently, the number of overweight and
obese patients (an independent risk factor for wound complications (2)) is increasing
rapidly. The National Health and Nutrition Examination Survey calculate that, as of 2000,
64% of American adults were either overweight or obese (3). These factors can potentially
lead to an increase in cesarean delivery wound complications. This article identifies clinical
practices that may reduce the risk of cesarean delivery wound complications and proposes
treatment guidelines that may help accelerate wound healing in disrupted wounds.
Back to Top
BACKGROUND
Wound complications include wound separation without infection, superficial wound
infection, deep wound infection, wound dehiscence, and rarely, necrotizing fasciitis (see
Appendix 1 for Centers for Disease Control and Prevention [CDC] definitions of wound
infection). The incidence of wound complications in the obstetric population varies in the
literature, with rates ranging from 2.8% to 26.6% (2,4–14). Although wound disruptions are
frequently preceded by infection, Martens et al (8) found a wound disruption rate of 1.7%
without infection. Fascial dehiscence occurs in 0.3% of all cesarean deliveries. The
incidence of necrotizing fasciitis is slightly less, with one review establishing a rate of 1.8
women per 1000 cesarean deliveries (5).
Back to Top
PATHOGENS
Microorganisms originating from the patient and/or the patient’s immediate environment
are the primary sources for postpartum wound infections. The genital tract and skin are the
most influential reservoirs for bacterial contamination. In a study by Martens et al (8), the
most prevalent pathogens cultured from infected cesarean wounds are Staphylococcus
epidermidis, Staphylococcus aureus, Escherichia coli, and Proteus mirabilis. In another
study of wound microbiology, Roberts et al (14) identified the most prominent pathogens
as cervicovaginal flora such as Ureaplasma species and Mycoplasma species.
Back to Top
WOUND HEALING PHYSIOLOGY
Wound healing occurs as a complex interplay of multiple biologic and cellular processes,
which are codependent. A review of these complexities will aid in understanding how
wound healing is disrupted and thus, how best to support the physiology of healing.
Full-thickness wound healing is carried out in three phases (Fig. 1): inflammation,
proliferation, and remodeling. The inflammatory phase occurs in response to the initial
injury and is manifested by the signs and symptoms of erythema, edema, warmth, and
drainage. The purpose of this phase is to control bleeding and establish a clean wound
bed. Hemostasis is initiated by activating the intrinsic and extrinsic coagulation pathways
and platelet aggregation. After hemostasis is established, the platelets break down,
releasing cytokines and growth factors such as platelet-derived growth factors,
transforming growth factors B1 and B2, platelet-derived epidermal growth factor, plateletactivating factor, insulin-like growth factor-1, fibronectin, and serotonin. These cytokines
and growth factors then attract inflammatory cells such as neutrophils and monocytes to
the wound site, which prevent infection by phagocytizing microorganisms. These white
blood cells also release growth factors such as fibroblast growth factor, epidermal growth
factor, vascular endothelial growth factor, tumor necrosis factor, interleukin-1, and
interferon-gamma, which trigger the activation of fibroblasts and keratinocytes to aid in
healing. In a clean wound, the inflammatory phase lasts approximately 3 days. Many
factors, however, can disrupt this cascade of cellular events, including infection, diabetes,
hypertension, and immunosuppression, thus causing a delay in wound healing.
The proliferative phase occurs next and consists of 3 components: angiogenesis, collagen
synthesis, and epithelialization. The purpose of angiogenesis is to create new vasculature
to supply blood to the damaged area to aid healing. Collagen synthesis fills the open
wound with new connective tissue, depositing a matrix material to serve as the basis for
wound closure and scar formation. These processes occur simultaneously and are
codependent.
When wounds heal by primary intention, like in sutured incisions, the rate of collagen
formation reaches a peak around the fifth postoperative day. It is possible to feel a ridge
under the suture line, called the “healing ridge,” which is produced by the newly formed
collagen. If this ridge is not palpable, impaired healing is likely, therefore placing the
wound at risk for disruption (15).
The amount of collagen necessary to fill the wound is related to the volume of the defect to
be filled. Wounds that are closed by approximating the incision with suture only need a
small amount of collagen. Wounds healed by secondary intention need greater amounts of
collagen and require a prolonged proliferative phase. Collagen production continues for
weeks or months and is dependent on specific oxygen and nutritional requirements. If the
host’s nutritional or vascular status is compromised, wound healing is delayed. This aspect
of healing is addressed in another section of this article.
Initially, the bed of a healing wound is filled with red, vascular granulation tissue. Over
time, the healing wound experiences a contraction of the wound bed with the opposing
edges slowly pulling together. There are several theories as to how this is mediated. One
theory proposes that wound contraction is triggered by myofibroblasts (modified
fibroblasts) that release factors that cause contraction of the skin and tissue around the
defect. Another theory suggests that fibroblast cells are actually moving among the
collagen matrix, causing a reorganization of the matrix, producing the wound bed
contraction (16).
Epithelialization is the third component in the proliferative phase. Epithelial cells migrate,
proliferate, and differentiate to resurface the wound defect, and can only work over a
moist, vascular wound surface. This fact was addressed in the work of Winter (17) and
then Hinman (18), forming the basis for the concept of moist wound healing. Dry or
necrotic wound surfaces thus impede epithelialization. In sutured wounds, epithelialization
occurs concurrently with collagen synthesis, whereas in open wounds, epithelialization
takes place after granulation tissue is formed.
The final phase of wound healing is remodeling, which can continue for over 1 year. In this
phase, the entire scar is reinforced through a process of collagen maturation. Collagen
fibers in nonwounded skin have a basketweave pattern. In wounded and scarred tissue,
the collagen produced is biochemically distinct from that in nonwounded tissue and is laid
down in a pattern parallel to the skin. The repaired scar requires time to strengthen.
Studies have shown that after 1 week, the strength of the scar is only 3% of normal skin,
after 3 weeks the strength is 20%, and after 3 months 80%. Thus, scar tissue is never as
strong as nonwounded tissue (16).
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RISK FACTORS FOR POSTCESAREAN WOUND COMPLICATIONS
Wound healing is distinctly shorter, more efficient, and organized when done through the
process of primary intention. Infection, inhospitable characteristics of the host (such as
vascular or chronic disease), suboptimal perioperative conditions (hypothermia), and
surgical technique that traumatizes tissue can all impede the normal phases of wound
repair (19,20). Risk factors for postcesarean wound complication will also impede wound
healing. These factors are described subsequently, and are summarized with
recommendations for prevention in Table 1.
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Obesity
Obesity is a major risk factor for postcesarean wound complications (7). The etiology of
wound complications in obese women is probably related to the poor vascularity of
subcutaneous fat, serous fluid collection, and hematoma formation. The obese gravida is
prone to more frequent wound complications even with the use of prophylactic antibiotics
(2). Cetin and Cetin (10) found that the wound disruption rate increased significantly with
thickened subcutaneous tissue. Women with subcutaneous tissue greater than 2 cm had a
wound disruption rate of 27.2% compared with 18.7% of controls. Studies have shown that
using a subcutaneous suture in all patients with greater than 2-cm subcutaneous depth
significantly reduces the risk of wound disruption (4,5,10,21–23). Specifically, closure of
excess subcutaneous tissue eliminates dead space, thus reducing the formation of
seromas.
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Diabetes
Impaired wound healing is frequently seen in patients with diabetes. Cruse and Foord (24)
reviewed infection rates in 23,649 patients and found that diabetics had 5 times the risk of
infection of nondiabetics, even with clean incisions. Although increased levels of HgA1c
were not shown to be positively correlated to surgical site infections in a study (25),
diabetes and postoperative hyperglycemia were independent risk factors for a surgical site
infection. Another study, by Zerr et al (26), compared infection rates before and after
implementation of stricter blood glucose goals and found that the rate of infection before
implementation was 2.4% and after implementation, the rate was 1.5%. Zerr demonstrated
that glucose levels above 200 mg/dL in the immediate postoperative period were
associated with an increased surgical site infection rate. Additionally, blood glucose levels
above 200 mg/dL at 48 hours postsurgery were significantly associated with deep wound
infection.
The explanation for the difference in diabetic wound healing is complex. The disparity
starts with alterations in the inflammatory response generated by injury or incision. These
differences in enzyme secretion and growth factor affect all the aspects of normal wound
healing such as collagen synthesis and deposition, leukocyte function, and tissue
perfusion. Although a growing body of research in experimental models of diabetes exists
to investigate the use of vitamin A, exogenous growth factors, and nitric oxide
supplementation to increase wound repair in diabetic patients, there are no specific
recommendations other than meticulous avoidance of hyperglycemia and strict regulation
of insulin to assist in wound healing. Specific blood glucose target levels have not been
identified, although as previously mentioned in the Zerr study, blood glucose over 200
mg/dL were shown to increase surgical site infections.
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Chorioamnionitis
Tissue infection and clinical circumstances that predispose to infection comprise the other
major reasons for suboptimal wound healing. Specifically, long labors, prolonged rupture
of membranes, and frequent vaginal examinations are all known risk factors for increasing
the rate of infection. Indeed, the intrauterine environment during labor can tremendously
impact postpartum healing. Tran et al (9) showed that chorioamnionitis increases the risk
for wound infection by a factor of 10.
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Corticosteroids
Patients on chronic corticosteroid therapy are especially at risk for poor wound healing.
Corticosteroids increase the risk of infection by suppressing inflammation, inhibiting
leukocyte function, retarding wound contraction, decreasing collagen matrix deposition,
and delaying epithelialization. Several studies support the assertion that vitamin A can
counteract some of the effects of corticosteroids (27,28). Specifically, vitamin A restores
the inflammatory response, promotes epithelialization and the synthesis of collagen,
further promoting wound healing and remodeling (27). Interestingly, vitamin A does not
restore the process of contraction in a healing wound. The recommended dose of vitamin
A has not been specifically researched, although current recommendations for
supplementation for those patients on steroids are 10,000 to 15,000 IU per day orally (29).
Vitamin A may also be administered topically so as not to reverse the systemic therapeutic
effects of steroids (28). According to Drugs in Pregnancy and Lactation (30), it is estimated
that topically applied retinoic acid is not detected in breast milk in clinically significant
amounts. Furthermore, vitamin A naturally occurs in breast milk. The recommended daily
allowance (RDA) for oral intake of vitamin A during lactation is 4000 IU; adverse affects to
the nursing infant are unknown.
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Stress
Stress, both physiological and psychologic, has a deleterious impact on wound healing. In
a study by Kiecolt-Glaser et al (31), wound healing was significantly longer in women who
were caregivers for relatives with dementia than controls. Broadbent et al (32) studied
wound fluid for levels of interleukin-1, interleukin-6 and matrix metalloproteinase-9,
cytokines, and enzymes that are required to attract phagocytes and regulate collagen
matrix production for wound healing. Patients reporting higher stress had significantly
lower levels of interleukin-1, interleukin-6, and matrix metalloproteinase-9. Stress also
causes endogenous hypercortisolemia from the sympathetic stimulation of adrenal glands
to release their glucocorticoid steroid reserves, which blunts the inflammatory phase of
wound healing. There is some evidence that psychoeducational therapy, stress reduction
techniques, hypnosis, music therapy, and acupuncture could reduce stress and reduce the
risk of wound complications (33–35).
In animal and human models, postoperative pain has been shown to have a negative
influence on immune function and wound healing (36); however, the impact on wound
healing using postoperative pain relief in humans is mixed. The stress response produced
by surgery includes changes in the pituitary and adrenal systems as well as metabolic
changes, which suppresses the immune system (37). It is interesting to note that regional
anesthesia (rather than general anesthesia) has the most support in the literature to
decrease the stress response from surgical procedures. Specifically, in a study by Koltun
(38), there was a significantly larger level of cortisol measured in the urine for 24 hours
postoperatively in patients who had received general anesthesia over that of patients who
received epidural anesthesia. Another finding showed natural killer cell cytotoxicity to be
significantly depressed in the general anesthesia group over the epidural anesthesia
group. Epidural anesthesia may block the afferent pain stimuli suppressing the stress
response, whereas general anesthesia may not.
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Nutrition
Nutrition and nutritional supplementation to improve wound healing has been written about
extensively, especially in the area of chronic wounds. Many recommendations have been
made particularly with regard to vitamin C, A, and zinc. The problem is that few human
studies are available that identify optimal levels of nutrients for wound healing and whether
nutritional supplementation has any impact at all on the rate of healing. Adequate nutrition
does seem essential to proper wound healing (39,40). This fact is frequently overlooked
but should be a priority of postoperative management. Protein requirements during
pregnancy are approximately 60 to 80 grams per day (41). Lactation increases those
requirements by 5 grams per day. Surgical procedures increase protein requirements
above these levels, yet also cause ileus, which further worsens a patient’s nutritional
status (15). Protein deficit has been directly correlated with wound dehiscence (39). Serum
prealbumin can be used as a guide to nutritional status. It has a half-life of 2 days and can
therefore be used as a short-term guide to protein levels (normal values 19–38 mg/dL,
severe protein depletion 0–5 mg/dL, moderate protein depletion 5–10 mg/dL, mild protein
depletion 10–15 mg/dL) (42). Although serum prealbumin levels are routinely ascertained
in the elderly at risk for malnutrition, it may be an area for future study in the obstetric
population. For patients who have been kept nothing by mouth during a protracted course
of labor, it may be useful to determine protein status and if found deficient, treat with high
protein supplement postoperatively. Clear liquid protein supplements are now available for
those patients who require clear liquids.
Vitamin supplementation is another consideration for those patients who are at risk for a
wound complication. Vitamin C is necessary for collagen synthesis, capillary wall integrity,
fibroblast function, and immunologic function. Vitamin C deficiency can delay wound
healing, although there is no strong evidence for supplementation in patients who do not
have scurvy. The RDA for vitamin C during pregnancy and lactation is 70 and 90 mg,
respectively. Supplemental doses of 1000 to 2000 mg per day are suggested in the
chronic wound literature (43).
Zinc supplementation for accelerating healing wounds has been studied with conflicting
results (44). Low serum zinc levels have been associated with impaired healing. Zinc aids
collagen formation and supports immune function. The RDA in pregnancy and lactation for
zinc is 15 and 19 mg per day, respectively. There are no evidenced-based
recommendations at this time for zinc supplementation.
Vitamin A is also frequently cited as necessary for wound healing. Vitamin A is necessary
for a normal inflammatory response, increasing the number of monocytes and
macrophages as well as stabilizing the intracellular lysosomes of the white blood cells
(29). Vitamin A has also been shown to accelerate collagen production in animals (40).
Doses and lactation implications have been discussed previously.
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Hypothermia
It has been hypothesized that mild perioperative hypothermia (defined as 2°C below the
normal core body temperature of 36.5°C) can promote postoperative wound infection by
causing vasoconstriction and impaired immune function. There is some controversy in the
literature as to the validity of this theory (19,45,46). Recent research, on balance, does
show a relationship between mild perioperative hypothermia and wound infection.
Although an evidenced-based recommendation cannot be made at this time, active
perioperative warming with a forced air blanket seems theoretically warranted.
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PREVENTION OF WOUND COMPLICATIONS
The first step in prevention of wound infection starts with the preparation of the operative
site. Table 2 presents the guidelines (modified from those proposed by the CDC) for
prevention of wound infection. Important to these suggestions is the fact that use of
antibacterial wash needs to start before surgical preparation of the patient in the operating
room. In fact, Hayek (47) showed a reduction in postoperative infection rates when
patients showered twice in 24 hours before surgery with chlorhexidine wash. The rate of
Staphylococcus aureus-infected wounds (attributable to skin contamination) dropped by
50% in the chlorhexidine group compared with the bar soap group. Other studies have
shown a decrease in skin colonization after showering with chlorhexidine (48). Additionally,
the manner in which the skin is prepared is also important. Specifically, avoidance of
shaving the skin is emphasized, because the use of a razor increases the risk of skin
breakage, which can allow pathogens direct access to the bloodstream.
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WOUND MANAGEMENT
Despite prophylactic measures and good surgical technique, a small percentage of
patients will still experience wound complications. Wound management should consider
strategies that expedite healing, minimize complications and cost. Furthermore, principles
of wound management should provide treatment to decrease cofactors that impede
healing. Hematomas and seromas are commonly observed problems after a cesarean
delivery. These types of situations require manual opening of the wounds to allow
drainage. After infection has been treated and all of the hematoma/seroma evacuated, an
open wound can be managed in 3 ways: secondary closure, secondary intention with
dressings, and secondary intention using negative pressure wound therapy.
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Secondary Closure
Secondary closure can be performed once a wound is free of infection or necrotic tissue
and has started to granulate. This procedure, which may be performed at the bedside
using local anesthesia and/or sedation, is done within 1 to 4 days after disruption or
evacuation of hematoma or seroma. A wound cleanser is first needed to prep the area,
and then a polypropylene mattress suture is used to close the skin and subcutaneous
tissue en bloc. An illustration of secondary closure technique is shown in Figure 2. The
suture may be removed 7 days after reclosure. The practice of using secondary closure to
repair superficial wound dehiscence is supported by several studies. Walters et al (49)
found secondary closure to be successful in 85% of cases. The mean time to complete
healing was 15.8 days in successful cases. Those patients randomized to healing by
secondary intention required a mean of 71 days of wound care to heal. In a study by
Dodson et al (50), patients who were treated with secondary closure required a mean of
17 days to heal, whereas those patients who were allowed to heal by secondary intention
took 61 days to complete wound healing. The results of these studies are striking. Wounds
healed on average 7 weeks sooner in the secondary closure group.
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Healing by Secondary Intention Using Dressings
Healing through secondary intention has historically been the most common way to
manage wound disruption. The rise in the incidence of chronic wounds has encouraged
the development of new wound care strategies and products to improve on the old “wet to
dry” dressings.
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MISCONCEPTIONS OF WOUND HEALING
It is important to describe several historical tenets of wound care that are outdated before
proceeding in a discussion of healing by secondary intention. Many studies have
documented that the use of products such as povidone iodine (51), Daikens solution (52)
iodophor gauze, and hydrogen peroxide (53) are cytotoxic to white blood cells and other
vital wound healing components. The use of these products can delay wound healing.
Irrigation with normal saline or commercial wound-cleansing solutions, which do not
contain any of the aforementioned components, will adequately remove surface bacteria
without disrupting the beneficial physiological process.
Another myth is that moist wounds are more prone to delayed healing because they are
more likely to become infected or break down and that keeping a wound dry promotes
healing. Research, in the early 1960s (17,18), proved that in fact, wounds that are kept
moist at all times are significantly quicker to heal than dry wounds. Moist wounds promote
autolytic debridement, support epithelial cell migration, and make dressing removal easier,
causing less trauma to viable tissue (54). In “wet to dry” dressings, saline-soaked gauze is
allowed to dry and then removed. This causes new tissue, which had adhered to the
gauze, to be pulled away, consequently destroying healthy tissue. This technique is more
appropriate for necrotic tissue debridement, and its validity is debated by wound care
experts who state that it should be used on very necrotic tissue and stopped when there is
viable tissue (55).
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MODERN WOUND CARE
Historically, dressing changes have been described as frequently as 4 times daily.
Frequent dressing changes will slow wound healing by reducing wound temperature,
disrupting cellular function and chemical reactions necessary for tissue repair. A study by
Thomas (56) has shown that it takes a wound 40 minutes after dressing change to return
to optimal temperature. Additionally, mitosis and leukocyte activities can be slowed for up
to 3 hours after wound cleansing. Temperature in humans must be kept between 97.5o to
99oF (36.4o to 37.2oC) for cellular processes to be optimal. Understanding wound healing
physiology and wound products allows wound care to be chosen appropriately for each
wound. Dressing changes can then be reduced to once daily or even every other day,
which enables the wound to maintain a physiological environment.
Modern wound care dressing selection considers factors such as the phase of healing, the
volume of exudate, and the presence of necrotic tissue to determine the type of dressing
that will be most supportive of wound healing. Dressing selection should optimize the
wound bed by decreasing the risk of infection, removing necrotic tissue, managing
exudate, eliminating dead space, and maintaining wound temperature.
The risk of infection can be reduced by using a nontoxic solution to cleanse the wound.
Necrotic tissue can be removed by sharp debridement or daily applications of enzymatic
debriders that act on necrotic tissue but have no effect on healthy tissue. Drainage can be
managed by using highly absorbent dressing material. Calcium alginate and foam are
examples of 2 newer materials used in wound care that are highly absorbent and have
been shown to be less painful during dressing changes than gauze. According to the
Cochrane Database (57), existing research is inadequate to show whether foam or
calcium alginate accelerates wound healing time. Wound care products are described in
Table 3. A source guide is provided in Table 4.
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Vacuum-Assisted Closure
Negative pressure wound therapy (NPWT), also known as vacuum-assisted closure,
received U.S. Food and Drug Administration approval in 1995. It uses controlled levels of
negative pressure to assist and accelerate wound healing by evacuating localized edema
with negative pressure. Bacterial colonization is reduced along with the evacuation of
wound drainage (58). Intermittent negative pressure causes in periodic release of
cytokines and inflammatory factors important to the previously mentioned phases of
wound healing (59). Negative pressure also increases localized blood flow and
oxygenation, thereby promoting a nutrient-rich environment that stimulates granulation
tissue growth (60). Such cellular proliferation encourages angioneogenesis, uniform
wound size reduction, and reepithelialization (58). This therapy has been used in chronic
wounds such as diabetic foot ulcers (61). NPWT accelerated wound closure significantly
over traditional gauze dressings in a study by Eginton et al (62). Recent research in
gynecologic oncology has looked at NPWT as a reliable and safe method to treat wound
failures (63,64). The results thus far have been encouraging.
The dressing used for negative pressure wound therapy is polyurethane foam that is
trimmed to fit the entire surface of the wound. Once the foam is placed, evacuation tubing
is laid on top of the foam. A clear, adhesive dressing is placed over the foam and tubing to
secure the unit to the wound site. The evacuation tubing has slits cut into the proximal end,
which will evacuate the wound fluid into a collection chamber located on the computerized
vacuum pump. The collection canister can be emptied as needed. Controlled negative
pressure is then applied by the vacuum-assisted closure device, which is a small
computerized pump (4 inches by 2 inches, weighing 2 pounds) with a rechargeable
battery. The tubing can be clamped and disconnected for short periods of time (no more
than 2 hours at a time for a maximum of 6 hours per day). Dressing changes are needed
every 48 hours. Indications, contraindications, and precautions are noted in Figure 3.
Illustrations of the NPWT dressing and the wound vacuum are seen in Figures 4 and 5.
Although negative pressure wound therapy is considerably more costly (approximately
$100 per day) than gauze dressings, the time to complete healing is significantly reduced
(62). Home health nursing visits can be reduced to 3 times weekly instead of everyday for
gauze-dressing changes. Our practice has seen significantly improved healing for patients
who have used the wound vacuum, particularly in obese patients. Closure of wound
dehiscence by secondary intention in such women can take months. Their deep
subcutaneous layer also makes secondary closure technically difficult to perform. NPWT
ensures that the subcutaneous wound environment remains free from seroma and
hematoma formation, thus assisting in maintaining an environment in which healing is
optimized.
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CONCLUSION
Recent developments using evidence-based research can decrease postcesarean
morbidity for women. Modern wound care strategies and products developed to support
wound healing physiology can minimize healing time if a wound complication occurs. The
information provided here can be useful to improve clinical outcomes in other surgical
procedures as well.