Download AEMT Transition - Unit 35

TRANSITION SERIES
Topics for the Advanced EMT
CHAPTER
Shock
35
Objectives
• Review the rates for hypoperfusion and
shock.
• Review aerobic and anaerobic
metabolism.
• Discuss the pathophysiological basis for
the stages of shock.
• Define treatment strategies for a
patient with shock.
Introduction
• “Shock” coined in 1743 to represent
what happens at the cellular level when
perfusion is bad.
• Now it has varied meanings, so the
term “hypoperfusion” has been
introduced.
Epidemiology
• Since “shock” is a response to another
body dysfunction, there is not a clear
estimation of “shock” rates.
• It is known, though, that when a shock
state does occur (for whatever reason),
the death rate is normally >20%.
• Some etiologies of shock cause 90%
mortality.
Pathophysiology
• Hypoperfusion can occur due to
multiple etiologies.
– Cardiac
– Volume
– Vascular
Pathophysiology (cont’d)
• In any instance, the final common
pathway is deterioration of cellular
oxygenation.
– Aerobic metabolism
– Anaerobic metabolism
Etiologies of Shock
Etiology of shock: fluid loss
Etiology of shock: pump failure
Etiology of shock: vasodilation
Pathophysiology (cont’d)
• Stages of shock
– Initial stage
– Compensatory (nonprogressive) stage
 Compensatory mechanisms
– Progressive (decompensatory) stage
– Refractory (irreversible) stage
Compensatory Mechanisms in Hypoperfusion
Effects of Shock on Body Organs and Systems
Recognizing the severity of shock
Assessment Findings
• Depending upon stage of shock:
– Tachycardia and tachypnea
– Anxious, aggressive, altered mental
status
– Narrowing pulse pressure
– Muscles become weak, then limp
Assessment Findings (cont’d)
• Depending upon stage of shock
(continued)
– Skin becomes cool and pale, typically
diaphoretic
– Final stages will have a dropping
systolic blood pressure, excessive
tachycardia, unresponsiveness and
death
Categories and types of shock
Characteristics of the Major Categories of Shock
Emergency Medical Care
• Spinal immobilization considerations
– Traumatic incidents
• Airway considerations
– Ensure open airway.
– Maintain airway if needed.
Emergency Medical Care (cont’d)
• Breathing considerations
– Use high-flow oxygen if breathing
adequately.
– PPV at either 8-10 or 10-12 (based on
pulse).
Emergency Medical Care (cont’d)
• Circulatory considerations
– Importance of pulse checks.
– If CPR warranted, push hard and fast.
– If major bleed present (whether arterial
or venous), control it as soon as
possible.
• Other considerations
– Maintain normothermia.
– Body positioning.
Emergency Medical Care (cont’d)
• Intravenous therapy
– Do not delay transport to initiate an IV.
– If volume expansion is needed, use a
large-bore catheter such as a 14 or 16
gauge.
– Administer IV fluids based on the clinical
presentation and as your protocol
allows.
Emergency Medical Care (cont’d)
• Volume Loss Etiology (Hypovolemia)
– Uncontrolled hemorrhage - infuse fluid
at a rate to maintain a systolic blood
pressure of 80 to 90 mmHg or until
radial pulses are able to be palpated.
– Controlled hemorrhage - infuse fluid to
maintain the systolic blood pressure
above 90 to 100 mmHg.
Emergency Medical Care (cont’d)
• Vasodilation Etiology
– Increase vascular resistance by
decreasing the vessel size.
– Fill the vessel with fluid.
– As an Advanced EMT, you will not likely
be able to administer vasopressors to
constrict vessels; however, you can
infuse fluids to fill the vascular space.
Emergency Medical Care (cont’d)
• Cardiogenic Etiology
– Typically the patient is normovolemic
and is experiencing difficulty in moving
the existing volume of blood.
– Restrict fluid administration to a keepopen rate once the intravenous line is
initiated.
Case Study
• During a local cage-fighting event, one of
the fighters was lifted and thrown down
onto the mat, landing on his head and
back. The fighter quit moving so you were
called in to assess the patient. He is a
young male, 22-23 years old, 185 pounds,
very muscular.
Case Study (cont’d)
• Scene Size-Up
– Standard precautions taken.
– Scene is safe, obvious struggle with the
fighting.
– Patient lying supine on floor of ring.
– No entry problems, egress may be
hampered due to large audience
present.
Case Study (cont’d)
• Primary Assessment Findings
– Patient responsive.
– Airway appears open, patient able to
speak.
– Breathing is rapid and shallow, breath
sounds present.
– Carotid and radial pulses present, radial
very weak.
Case Study (cont’d)
• Primary Assessment Findings
– Peripheral skin is warm, diaphoretic.
– No major bleeds or angulations noted,
patient not moving extremities.
Case Study (cont’d)
• Is this patient a high or low priority?
Why?
• What interventions should be provided
at this time?
Case Study (cont’d)
• What is the significance of the radial
pulse being weak as compared to the
carotid?
• What could be the etiologies of shock
that could create this finding?
Case Study (cont’d)
• Medical History
– Patient states none
• Medications
– Various muscular training supplements
• Allergies
– None
Case Study (cont’d)
• Pertinent Secondary Assessment
Findings
– Pupils reactive to light.
– Airway patent and maintained by the
patient.
– Breathing is rapid, alveolar sounds
diminished.
– Peripheral pulse now absent, carotid
now becoming weaker.
Case Study (cont’d)
• Pertinent Secondary Assessment
Findings (continued)
– Skin warm and dry, no motor or sensory
motion below shoulders.
– B/P 100/50, HR 62, RR 26.
– SpO2 95% on room air, 99% on oxygen.
Case Study (cont’d)
• Is this patient in a state of shock?
• If yes, what stage of shock?
• Are there now findings that would
cause you to refine your field
impression?
Case Study (cont’d)
• What normal compensatory mechanism
for shock is not active in this patient?
• Why would this etiology of shock cause
the patient's respiratory status to be
what it is?
Case Study (cont’d)
• Care provided:
– Patient kept supine.
– High-flow oxygen via NRB mask.
– Full spinal immobilization done very
carefully.
– Paramedic intercept started early.
– Patient packaged and taken to ambulance
via wheeled cot.
– Transport to hospital initiated.
Summary
• Hypoperfusion is going to be one of the
most common syndromes seen by the
Advanced EMT.
• Since this is the final common pathway
for all types of shock, the Advanced
EMT must be able to recognize the
cause of shock – not just the
symptoms, in order to provide the best
care.