Download Emergencies and Life Threatening Problems in Sports Medicine

Shock
Year 4 Tutorials
AB
C DE
Objectives:

What is shock?

Types of shock

Management principles
Shock Definition:
State of inadequate tissue perfusion and tissue
oxygenation as a result of a deficiency in the
circulation
Types of Shock:



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Distributive – Septic
Anaphylactic
Neurogenic
Cardiogenic
Obstructive – Tension pneumothorax
Cardiac tamponade
Hypovolaemic
CARDIAC PHYSIOLOGY
BP = CO x SVR
HR x SV
•Contractility
•Preload (ventricle stretch)
•Afterload
Normal vascular tone
determined by sympathetic
innervation
Distributive - Sepsis

SIRS = 2 of
 RR > 20 breaths per minute
 WCC < 4 or > 12
 Heart rate > 90 beats per minute
 Temperature: Fever > 38.0 °C or < 36.0 °C

Sepsis = SIRS + Evidence of infection
Distributive - Septic

Massive vasodilation

BP = CO x SVR (
)

Often dehydrated

Fluids & antibiotics,

Vasoconstrictors.
Distributive - Anaphylaxis

Massive vasodilation

Type 1 hypersensitivity

Treatment:


Fluids, adrenaline,
chlorphenamine, steroids
?Anaesthetist
Distributive - Neurogenic

Massive vasodilation

Loss of sympathetic
vascular tone.

Fluids and
vasoconstrictors.
Cardiogenic shock

PUMP failure!

Cannot empty pump

Causes:

Acute MI

BP = CO x SVR


Other Conditions

CO = HR x SV

(
contractility)
Large Infarction
Papillary muscle rupture




Septic shock
Myocarditis
Arrhythmias
Drugs – eg beta-blocker
overdose
Myocardial contusion
Cardiogenic shock

Treat underlying
cause if possible

Inotropes.
Balloon pump

Obstructive –Tension Pneumothorax

Accumulation of air
under pressure in the
pleural space.

1-way valve

Mediastinal shift:
preload & afterload =
SV
Obstructive –Tension Pneumothorax

Treatment:
 Needle decompression
 Chest drain
Obstructive – Cardiac Tamponade

Accumulation of fluid in
the pericardial space,
resulting in reduced
ventricular filling

Rapid filling of only 150ml
causes compromise
Obstructive – Cardiac Tamponade

Becks triad:




increased jugular venous
pressure,
hypotension
diminished heart sounds.
Treatment: needle
pericardiocentesis
Hypovolaemic Shock


The system is DRY.
Causes:




Haemorrhage
Sepsis
D&V
BP = CO x SVR

CO = HR x SV
Hypovolaemic / Haemorrhagic

Where is the Blood?

Revealed

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On the floor, at the scene
Concealed




Chest
Peritoneal/Pelvis
Long bones
Retroperitoneum
Hypvolaemic shock management:

Treat underlying cause
 haemorrhage control – 1st aid, angio, theatre

Venous access / fluids

Fluid replacement
Vascular access:

TWO large venflons

Where?
 Anticubital fossa

Consider IO
Take samples – X-match

Initial fluid therapy:

Crystalloid

Cross matched

Colloid

Type specific

Consider warming

‘O’ negative
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Massive transfusion
protocol
Response to fluid treatment:

General

Urine - 30ml / hour (0.5mg/kg)

Acid / Base balance (lactic acidosis)
Shock summary

Distributive –


vasodilation - reduced
SVR
Cardiogenic –

reduced heart rate /
stroke volume - pump
failure

Obstructive –


reduced stroke
volume – blood can’t
get in or out
Hypovolaemic –

reduced stroke
volume - lack of blood
volume
May be a combination
Shock summary





ABCs
Assess degree and cause
Intervene:
 Treat underlying cause
 Maintain CO and SVR - fluids, vasocostictors,
inotropes
Reassess
Get HELP
Questions
A&E Department,
Aberdeen Royal Infirmary
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