Hypotension - Guidelines for Crises in Anaesthesia Hypotension is commonly due to unnecessarily deep anaesthesia, the autonomic effects of neuraxial block, hypovolaemia or combined causes. You should rapidly exclude a problem in adequate oxygen delivery, airway and breathing first. ❶ Adequate oxygen delivery • Pause surgery if possible. • Increase fresh gas flow AND give 100% oxygen AND check measured FiO2. • Visual inspection of entire breathing system including valves and connections. • Rapidly confirm reservoir bag moving OR ventilator bellows moving. ❷ Airway • Check position of airway device and listen for noise (including larynx and stomach). • Check capnogram shape compatible with patent airway. • Check airway AND airway device are patent (consider passing suction catheter). ❸ Breathing • Check chest symmetry, rate, breath sounds, SpO2, measured VTexp, ETCO2. • Feel the airway pressure using reservoir bag and APL valve <3 breaths. • Exclude high intrathoracic pressure as a cause. ❹ Circulation • Check heart rate, rhythm, perfusion, recheck blood pressure. • If heart rate <60 bpm consider giving anticholinergic drug (Box B). • Consider giving vasopressor (Box C) and positioning (e.g. move head down). • Consider fluid boluses (250 ml adult, 10 ml.kg-1 paediatric). • If heart rate >100 bpm sinus rhythm, treat as hypovolaemia: give i.v fluid bolus. • If heart rate >100 bpm and non-sinus → 2-7 Tachycardia. ❺ Depth • Ensure correct depth of anaesthesia AND analgesia (consider risk of awareness). ❻ Exclude potential surgical causes (Box D) – discuss with surgical team. ❼ Consider causes in Box E and call for help if problem not resolving quickly. DON’T FORGET! • Consider whether you could have made a drug error. • Pneumothorax and/or high intrathoracic pressure can cause hypotension. • Also consider: o Cardiac ischaemia → 3-12 o Anaphylaxis → 3-1 o Cardiac tamponade → 3-9 o Local anaesthetic toxicity → 3-10 o Sepsis → 3-14 o Cardiac valvular problem o Endocrine cause (eg steroid dependency) By Association of Anaesthetists @ https://twitter.com/AAGBI Quick Reference Handbook - Guidelines for crises in anaesthesia #Hypotension #Differential #Anesthesiology #Anesthesia #Intraoperative #Checklist #Diagnosis #Management #Workup
