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ABCDE management of a critically ill patient

This protocol should be used for critically ill patients (i.e. with very unstable observations or reduced GCS). 



  • It’s patent if the patient can talk and breathing is not noisy
  • It’s not if there are secretions, the patient has aspirated, is snoring/ GCS<8, or stridor is present
  • Look inside the mouth – are there any obstructions? Is there mucosal oedema?


  • Consider:
    • Remove dentures/debris (Magill forceps are in crash trolley)
    • Suction
    • Airway opening manoeuvres (e.g. jaw-thrust or head-tilt/chin lift)
    • Recovery position if vomiting/aspiration risk
    • Oropharyngeal / nasopharyngeal airways
    • Intubation (if GCS <8) 
  • Cricothyroidotomy may be required in upper airway obstruction where intubation is not possible
  • Treat cause
    • Treat any evident causes (e.g. anaphylaxis, foreign body)



  • Pulse oximetry
  • RR
  • Chest exam
    • Cyanosis
    • Tracheal deviation
    • Chest inspection (accessory muscle use, deformities)
    • Expansion
    • Percussion
    • Auscultation
  • Calves
  • Tests
    • ABG (if low saturations or low GCS)
    • CXR (if lung pathology suspected)


  • 15L/minute O2 via non-rebreather mask 
    • WARNING: take care if COPD (unless they are in respiratory distress/critically unwell and need high-flow oxygen, start at 24-28% venturi and aim for sats 88-92%. Titrate to ABG results.)
  • Consider non-invasive or invasive ventilation if hypoxaemic, or hypercapnic respiratory acidosis despite maximal therapy
  • If respiratory effort is inadequate, it must be supported (e.g. ventilate with bag-mask)
  • Treat cause
    • Treat any evident causes (e.g. pneumothorax, asthma/COPD exacerbation, opiate overdose, PE)



  • Capillary refill (central)
  • Pulse rate, rhythm and volume
  • Blood pressure (look at trend)
  • Temperature
  • Auscultate heart, check JVP and look for signs of fluid overload
  • Assess fluid balance and organ perfusion (IN e.g. fluids, intake; OUT e.g. catheter/urine, drains, vomit)
  • Tests
    • Place wide-bore IV Cannula and take bloods (also do VBG for fast results if ABG not required)
    • Apply 3-lead cardiac monitoring
    • ECG (if any concern)•Catheter and fluid balance monitoring (if hypotensive/unwell)


  • Hypotension
    • Lay supine and elevate legs
    • Fluid challenge = 500ml 0.9% saline/Hartmann’s solution STAT and monitor response by HR, BP and UO (see prescribing notes on fluids)
    • WARNING: take care if significant heart failure history (use 250ml if they need it)
  • Shock
    • 2 large bore IV cannulas
    • Fluid challenge = 1L 0.9% saline/Hartmann’s solution STAT
    • Replace blood with blood (can give O negative or urgent typing takes 15 minutes). In massive blood loss, call 2222/lab and activate the massive blood loss protocol to get packed red cells + FFP ± platelets
  • Further management – use clinical judgement and assessment of fluid status
    • Respond fully: consider maintenance fluids                     
    • Responds but BP falls again: may require further fluids (adequate resuscitation depends on patient and degree of deficit but is usually 20-30ml/kg given quickly)
    • No response: patient may be fluid overloaded/in cardiogenic shock (avoid further fluids) or very deplete (requiring further fluids)
  • Escalation
    • If patient is hypotensive and overloaded, they need inotropes
    • If patient is still hypotensive despite adequate fluid resuscitation (20-30ml/kg), they need vasopressors      
  • Treat cause e.g. arrhythmia (further management inarrhythmia notes), sepsis, bleeding etc.



  • DEFG – Don’t Ever Forget Glucose
  • GCS/AVPU score
  • Pupils reactivity and symmetry
  • Pain assessment
  • Check drug chart
  • Tests
    • CT brain (if intracerebral pathology needs to be excluded)


  • Correct glucose if low
  • Give analgesia if pain (e.g. morphine 10mg in 10ml slow IV injection titrated to pain)
  • Look for and treat cause
  • Look for and treat causes of low GCS, e.g. hypoglycaemia, morphine/sedative use, focal neurology to suggest intracranial pathology, hypercapnia, post-ictal

Everything else


  • Exposure (look for bleeds, rashes, injuries, drain/catheter output, lines) 
  • Examine abdomen
  • Focussed exam of relevant systems


  • Manage any other abnormal findings as appropriate 

Notes on ABCDE assessment

NB: only move to the next letter when the one before has been treated, and keep re-assessing ABCDE from the start as necessary.

Investigations to find cause

  • Review patient’s notes
Bloods (mark as urgent)ABG (if low saturations/low GCS), venous bloods (group and save, FBC, U&Es, CRP, LFTs ± amylase, clotting, troponin, VBG etc.), capillary glucose, blood cultures (if pyrexial)
Orifice testsUrine dip, urine/sputum/faeces culture, urine βHCG
X-rays / imagingPortable CXR, CT brain (if neurology or low GCS in the absence of other causes)
ECG± 3-lead cardiac monitoring
Special testsDepending on likely cause

Condition specific treatment

  • See acute management notes on specific conditions
  • e.g. MONAC for MI, furosemide for heart failure, anticoagulation/thrombolysis for PE, sepsis six, fluids and insulin for DKA, terlipressin and OGD for bleeding varices

Request help as required

  • Inform senior
  • Refer to other specialty if indicated, for example:
    • Medical registrar: medical problems
    • Endoscopist on call: upper GI bleeding
    • Surgical registrar: surgical problems and bleeding
    • Cardiology registrar: MI/arrhythmia 
    • Gynaecological registrar: ruptured ectopic
    • Intensive/high-dependency care registrar: if patient may need higher level of care / airway concerns

Document in patient’s notes

  • Document with a brief case summary, ABCDE headings with findings and management
  • Review patient and results as necessary