Critical Care Emergencies 15Shocked Patient
5 Facial burns and or steam inhalation (see p. 250)
(i) Send blood for ABGs and a carboxyhaemoglobin level.
(ii) Give 100% oxygen and nebulized salbutamol 5 mg, and refer to
intensive care or specialist burns unit if there is an associated
respiratory burn.
(iii) Be prepared to intubate if gross laryngeal oedema occurs.
6 Angioedema with laryngeal oedema (see p. 111)
(i) Give high-dose oxygen and 1 in 1000 adrenaline (epinephrine)
0.3–0.5 mg (0.3–0.5 mL) i.m. into the upper outer thigh, repeated
every 5–10 min as necessary.
(ii) Change to adrenaline (epinephrine) 0.75–1.5 μg/kg i.v. if
circulatory collapse occurs, i.e. 50–100 μg or 0.5–1.0 mL of 1
in 10 000 adrenaline (epinephrine), or 5–10 mL of 1 in 100 000
adrenaline (epinephrine) for a 70 kg patient, given slowly.
(iii) Endotracheal intubation may still be required, performed by a
skilled doctor with airway training, or even a cricothyrotomy.
General approach
DIAGNOSIS
1 ‘Shock’ is defined as acute circulatory failure leading to inadequate
end-organ tissue perfusion with oxygen and nutrients. It is a clinical diagno-
sis with a high mortality that depends on the underlying cause, its duration
and response to treatment.
(i) Shock progresses from an initial insult to compensated
(reversible), decompensated (progressive) then finally refractory
(irreversible) shock.
(ii) Compensated shock
Physiological mechanisms initially compensate to combat the circulatory
failure. These include hyperventilation as a result of acidosis, sympathetic
mediated tachycardia and vasoconstriction, and the diversion of blood
from the gastrointestinal and renal tracts to the brain, heart and lungs.
(iii) Decompensated shock
Inadequate tissue perfusion results in increasing anaerobic glycolysis
and metabolic acidosis, cellular injury with fluid and protein leakage,
and deteriorating cardiac output from vascular dilatation and myo-
cardial depression.
(iv) Irreversible shock
This ensues when vital organs fail and cell death occurs. Severe
and progressive shock states cause multi-organ failure (MOF) or