Severe Hypothermia Case 1

It is midwinter and snowing. You are the senior doctor in the ED in a large urban teaching hospital. The ambulance service inform you by phone that they will be arriving in 10 minutes with a young female in cardiac arrest. She was found in a park with an empty bottle of rum. She has no detectable respiratory effort or pulse.

List at least five key things you would do before they arrive.

The female patient arrives with bag mask ventilation and CPR in progress. Her clothes have been removed and warm blankets applied. She is very cold to the touch and is in ventricular fibrillation on the monitor. Two 14-gauge cannulae are placed in the ante cubital fossae.

How long should you take to confirm cardiac arrest?

The patient is placed on an external air re-warmer on a Resus trolley, attached to monitoring and CPR is continued. Primary survey reveals no respiratory effort and a 60-second pulse check confirms no cardiac output. The rhythm is confirmed as VF. A biphasic shock is delivered with no effect.

Bag valve mask ventilation is continued. What rate would you ask for this to be delivered at?

Post-shock CPR is reinstituted. An oesophageal temperature probe is placed and she is intubated by which time your first cycle of CPR is complete and the patient remains in VF. The oesophageal temperature is 27.6^°C.

What would you do now?

The initial blood gas sample is as follows:

pH 7.04, CO₂ 2.6 kPa, HCO₃ 9 mmol/L, lactate 14mmol/L, K 3.1 mmol/L, Na 139 mmol/L, glucose 12 mmol/L, Hb 19gd/L. Regarding these results:

What measures will you commence to re-warm this patient while waiting for bypass – or if you do not have access to bypass?

Arterial and central access are obtained, the arterial line is placed brachially and the central line in the internal jugular. Ultrasound is used to guide placement – you could have placed these femorally but know that bypass will be femoro-femoral. They are not immediate life saving manoeuvres so follow the warming interventions. You are now at 30 minutes into the arrest and the patient is at 30.1^°C. She remains in VF.

Should a further shock should be given?

The patient reverts to sinus rhythm with an arterial wave form following a biphasic shock. The pulse rate is 44 beats per minute and the blood pressure 72/46 mmHg. Some 4 minutes later, the patient is noted to be in a broad complex tachycardia with an invasive BP of 40/15. Core temperature is 30.3^°C. An ABG taken a few moments earlier shows pH 7.18, HCO3 12, Lactate 13 mmol/L, K 2.8 mmol/L, Na 136 mmol/L, and glucose 9 mmol/L.

What action(s) would you take?

The cardiopulmonary bypass team has now arrived and ask if they should institute bypass as the patient now has a perfusing rhythm.

Is cardiopulmonary bypass still indicated?