Management of shock

Management
If BP unrecordable, call the cardiac arrest team.

Specific measures:
Anaphylaxis: refer to later blog entry
Cardiogenic shock: refer to later blog entry

Septic shock: (if no clue to source): IV cefuroxime 1.5g/6-8h (after blood culture) or gentamicin, do levels; reduce in renal failure) + antipseudomonal penicillin, eg ticarcillin (as Timentin, max dose 3.2g/4h IVI). Give colloid, or crystalloid, by IVI. Refer to ITU if possible for monitoring inotropes; aim for CVP 8-12mmHg, MAP >65mmHg. Urine >35ml/h. Low dose steroids may help as may recombinant human activated Protein C.

Hypovolaemic shock: Fluid replacement: saline or colloid initially; if bleeding use blood; Titrate against BP, CVP, urine output. Treat the underlying cause. If severe haemorrhage, exsanguinating, or more than 1L of fluid required to maintain BP, consider using group-specific blood. Correct electrolyte abnormalities. Acidosis often responds to fluid replacement.

Heat exposure (heat exhaustion): tepid sponging + fanning; avoid ice and immersion. Resuscitate with high-sodium IVI, such as 0.9% saline ± hydrocortisone 100mg IV. Dantrolene seems ineffective. Chlorpromazine 25mg IM may be used to stop shivering. Stop cooling when core temperature <39°C.

Shock

Shock
Essence
Circulatory failure resulting in inadequate organ perfusion. Generally systolic BP is <90mmHg. Signs: pallor, pulse, capillary return (press a nailbed), air hunger, oliguria. Causes are either pump failure or peripheral circulation failure.

A)Pump failure
Cardiogenic shock
Secondary: pulmonary embolism, tension pneumothorax, cardiac tamponade.
Peripheral circulation failure
Hypovolaemia
Bleeding: trauma, ruptured aortic aneurysm, ruptured ectopic pregnancy. Fluid loss: Vomiting (eg GI obstruction), diarrhoea (eg cholera), burns, pools of sequestered (unavailable) fluids (third spacing, eg in pancreatitis). Heat exhaustion may cause hypovolaemic shock (also hyperpyrexia, oliguria, rhabdomyolysis, consciousness, hyperventilation, hallucination, incontinence, collapse, coma, pin-point pupils, LFT up, and DIC,
Anaphylaxis
Sepsis: Gram -ve (or +ve) septicaemic shock from endotoxin-induced vasodilatation may be sudden and severe, with shock and coma but no signs of infection (fever, WCC elevated).
Neurogenic: eg post-spinal surgery.
Endocrine failure: Addison's disease or hypothyroidism;
Iatrogenic: Drugs, eg anaesthetics, antihypertensives.
Assessment
ABC.
ECG: rate, rhythm, ischaemia?
General: cold and clammy cardiogenic shock or fluid loss. Look for signs of anaemia or dehydration skin turgor, postural hypotension? Warm and well perfused, with bounding pulse septic shock. Any features suggestive of anaphylaxis—history, urticaria, angio-oedema, wheeze?
CVS: usually tachycardic (unless on B-blocker, or in spinal shock and hypotension. But in the young and fit, or pregnant women, the systolic BP may remain normal, although the pulse pressure will narrow, with up to 30% blood volume depletion. Difference between arms—aortic dissection?
JVP or central venous pressure: If raised, cardiogenic shock likely.
Check abdomen: any signs of trauma, or aneurysm? Any evidence of GI bleed? check for melaena.

Breathlessness: emergency presentations

Breathlessness: emergency presentations

Wheezing?
Asthma
COPD
Heart failure
Anaphylaxis

Stridor?
(Upper airway obstruction)
Foreign body or tumour
Acute epiglottitis
Anaphylaxis
Trauma, eg laryngeal fracture

Crepitations?
Heart failure
Pneumonia
Bronchiectasis
Fibrosis

Chest clear?
Pulmonary embolism
Hyperventilation
Metabolic acidosis, eg diabetic ketoacidosis (DKA)
Anaemia
Drugs, eg salicylates
Shock (may cause air hunger)
Pneumocystis pneumonia
Central causes

Others
Pneumothorax—pain, increased resonance
Pleural effusion ”stony dullness"