Overview #
For immediate response to hypotension that breaches MET call criteria (systolic BP < 90 mmHg)
Key Points
- Hypotension: blood pressure of < 90/60mmHg
- Shock: A state of circulatory failure causing inadequate oxygen delivery to meet cellular metabolic needs and oxygen consumption requirements [1]
- subclassified into: hypovolaemic, distributive, obstructive, cardiogenic or mixed shock
- Hypotension can be a late sign of shock
- Assess every hypotensive patient for signs of shock, and if present seek urgent senior review
- A structured approach to the assessment of a hypotensive patient is provided below
- IV fluid resuscitation is a key component of the ward management of shock, hypotension refractory to fluid resuscitation warrants urgent referral to ICU
Triage #
Immediate – should be attended immediately
Causes #
The causes of hypotension can be conceptualised as the same as the causes/classification of shock:
1. Hypovolaemic
- Bleeding
- Dehydration
- Gastrointestinal losses
- Renal losses
2. Distributive
- Sepsis
- Systemic inflammatory response syndrome
- Anaphylaxis
- Liver failure
- Neurogenic
- Spinal/epidural anaesthesia
- Brain or spinal cord injury
- Endocrine shock: Addisonian crisis, myxoedema
3. Obstructive
- Pulmonary embolism
- Tension pneumothorax
- Pericardial tamponade
4. Cardiogenic
- Myocardial infarction
- Valvular disease (eg: stenosis, regurgitation, rupture)
- Arrhythmia
- Medication effects (eg: beta-blockers, calcium channel blockers)
5. Mixed
· A combination of the above causes
Clinical Assessment #
1. Ensure accurate blood pressure measurement
- Take BP manually with the correct sized cuff
- A cuff too small for the patients arm will overestimate readings, while a cuff too large will underestimate the reading
- Automated non-invasive blood pressure measurements can be unreliable in patients with an arrythmia
2. Examine for signs of shock (if present seek urgent senior review)
- Altered mental status
- Tachypneoa
- Tachycardia
- Delayed capillary refill
- Mottled skin
- Oliguria (<0.5mls/kg/hr)
- Patient reporting feeling dizzy or unwell
3. Assess for potential cause of hypotension/shock
| Sign | Significance |
| Tachycardia | Tachycardia is a compensatory response to hypotension/shock but may not be present:· if the patient has received beta or calcium channel blockers, or if the cause is neurogenic or endocrine |
| Cardiac murmur | Consider valvular disease |
| Absent breath sounds | Consider tension pneumothorax |
| Tracheal deviation | Suspect tension pneumothorax |
| JVP | If elevated consider obstructive and cardiogenic causes |
| Temperature of peripheries | Cool peripheries can be a sign of shockWarm peripheries in a shocked patient suggests a distributive cause |
| Unilateral swollen limbs | Consider DVT |
| Fever | Consider sepsis |
| Peritonism | Consider intra-abdominal sepsis or haemorrhage |
| Evidence of skin infection | Consider sepsis |
| Angiooedema, rash, wheeze | Suspect anaphylaxis |
4. Chart review
· Review trend of heart rate, blood pressure and respiratory rate
· Review notes, post-operative reports, and recent investigations
· Review drug chart, particularly for any antihypertensive medications
Investigation #
Initial investigations for undifferentiated shock
| Investigation | Significance |
| VBG/ABG | Metabolic acidosis and/or lactate >2mmol/L suggests shockLow Hb – suggests haemorrhage |
| FBE, UEC, LFT, CRP | Low Hb – suggests haemorrhageElevated urea – consider upper GI bleedingElevated inflammatory markers – consider sepsis LFT and UEC – shock can cause acute kidney and liver injury, fulminant hepatic failure can also be a cause of distributive shock |
| Serial troponins | Check for myocardial injury/ischaemia |
| ECG | Check for:· arrythmia· ischaemia· electrical alternans (tamponade)· right heart strain (pulmonary embolus) |
| CXR | Check for pneumonia (sepsis), tension pneumothorax, pulmonary oedema (heart failure) |
Further investigations depending on clinical suspicion
| Investigation | Significance |
| Group and hold Coagulation profile | If suspicion of haemorrhage |
| Septic screen | If suspicion of sepsis |
| BNP | If suscpicion of cardiac failure |
| Random and morning cortisol | If suspect Addisonian crisis/adrenal insufficiency[SS1] |
| TFTs | If suspicion of myxoedema |
| Bedside TTE* | If suspicion of cardiogenic shock. Looking for cardiac function, pericardial effusions/tamponade and valvular disease. |
| CTPA* or VQ scan* | If suspicion of PE |
| CT Chest/Abdomen/Pelvis* | If suspicion of haemorrhage or occult infection |
| CT angiogram* | If suspicion of bleeding or dissection |
Management #
For all patients
- Urgent escalation to a senior doctor or MET call if evidence of shock
- Establish wide bore IV access available and draw bloods
- Consider fluid bolus (unless evidence of pulmonary oedema)
- Consider witholding antihypertensive and diuretic medications
- Investigation as above
If evidence shock and not improving with one or two fluid boluses escalate to senior doctor / ICU for review and consider MET Call
Management – specific management of underlying cause #
Hypovolaemic shock
Haemorrhage
- Apply direct pressure to external bleeding if possible
- Arrange packed red blood cells (PRBC) transfusion and consider activating massive transfusion protocol as required
- Arrange urgent surgical/endoscopic/interventional radiological intervention for noncompressible bleeding
References #
1. Gaieski DF, Mikkelsen ME, Evaluation of and initial approach to the adult patient with undifferentiated hypotension and shock. In: Parsons PE, Hocksberger RS, editors. UpToDate. [Internet]. UptoDate; 2020 [updated 2021 Feb 23; cited 2021 Sep 29]. Available from: https://www.uptodate.com/contents/evaluation-of-and-initial-approach-to-the-adult-patient-with-undifferentiated-hypotension-and-shock?search=hypotension&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
2. Henry S. ATLS Advanced Trauma Life Support Student Course Manual. 10th ed. Chicago (IL): ACS American College of Surgeons; 2018. Chapter 3, p. 49.
Contributors
Reviewing Consultant/Senior Registrar
Dr Kwan Yun Lee
Dr Scott Santinon
