Distributive shock

This happens when the blood vessels are abnormally dilated and presents with a low blood pressure, tachycardia and warm peripheries. There are 3 causes of this type of shock:

NEUROGENIC SHOCK

T09.3 + (Y34.99/R57.8)

DESCRIPTION

Occurs in spinal cord trauma when there is an interruption of the sympathetic chain causing vasodilatation.

GENERAL MEASURES

Check circulation, airway and breathing.

Spinal cord immobilisation.

Exclude other injuries that could cause low blood pressure.

MEDICINE TREATMENT

  • Oxygen if saturation <94%.

LoEI [26]

  • Sodium chloride 0.9%, IV.

LoEI [27]

LoEIII

  • Adrenaline (epinephrine), IV infusion, start at 0.05 mcg/kg/minute titrated according to the response.
    • Dilute 10 mg (10 ampoules) of adrenaline 1:1 000 in 1 L sodium chloride 0.9%.
    • Infuse according to weight and clinical response.
    • Infusion rate: mL/hour
Weight in kg
mcg/kg/minute 50 60 70 80 90 100 110
0.05 15 18 21 24 27 30 33
0.1 30 36 42 48 54 60 66
0.2 60 72 84 96 108 120 132
0.3 90 108 126 144 162 180 198
0.4 120 144 168 192 216 240 264
0.5 150 180 210 240 270 300 330
0.6 180 216 252 288 324 360 396
0.7 210 252 294 336 378 420 462
0.8 240 288 336 384 432 480 528
0.9 270 324 378 432 486 540 594
1 300 360 420 480 540 600 660

SEPTIC SHOCK

R57.2

DESCRIPTION

Shock caused by a confirmed or suspected infection, with vasodilatation, increased capillary permeability, and decreased contractility of the heart.

GENERAL MEASURES

Check airway, breathing and circulation.

MEDICINE TREATMENT

  • Oxygen if saturation <94%.

LoEI [28]

Take blood culture (or any other tissue/body fluid), then administer appropriate parenteral broad spectrum antibiotics urgently, e.g.:

  • Ceftriaxone, IV, 2 g daily.

LoEII [29]

Perform a fluid challenge for hypotension:

  • Sodium chloride 0.9%, 500 mL boluses over 30 minutes, whilst monitoring clinical response until 30 mL/kg has been achieved.
    • Assess BP and pulse rate response. Response is defined by a good urine output (>0.5 mL/kg/hour) and adequate cerebral perfusion rather than an absolute BP value.

Balanced solutions may be appropriate in some patients (i.e. presentation with hyponatraemia, previous renal placement therapy):

LoEI [30]

  • Balanced solution, e.g.:
  • Ringer lactate, 500 mL boluses over 30 minutes, whilst monitoring clinical response, until 30 mL/kg has been achieved.
    • Assess blood pressure and pulse rate response. Response is defined by a good urine output (>0.5 mL/kg/hour) and adequate cerebral perfusion rather than an absolute blood pressure value.

Avoid over-hydrating as this could exacerbate hypoxia associated with adult respiratory distress syndrome.

If no haemodynamic response to early aggressive fluid resuscitation:

  • Adrenaline (epinephrine), IV infusion, 0.05 mcg/kg/minute titrated according to the response.
    • Dilute 10 mg (10 ampoules) of adrenaline 1:1000 in 1 L sodium chloride 0.9%.
    • Infuse according to weight and clinical response. (Aim for target MAP 65 mmHg and urine output 0.5 mL/kg/hour).
    • See Neurogenic shock for the infusion rate.