Rescuer Fatigue Using Two Thumb Versus Two Finger Method During Simulated Neonatal Cardiopulomnary Resuscitation

The majority of newborns transition successfully from intrauterine to extrauterine life without any assistance. Less than 1% of all newborns will require extensive neonatal resuscitation involving chest compressions (CC) and medications at birth 1. Chest compressions are indicated for those newborns whose heart rate remains less than 60 beats per minute despite adequate ventilation 1. The American Heart Association (AHA) identifies two different methods of delivering chest compressions; a) the two-thumb (TT) method and b) the two-finger (TF) method. The two-thumb method is favoured by the AHA as it results in higher blood pressure and coronary perfusion pressures and can also be delivered from the head of the bed during umbilical catheter insertion 1.

The quality of CC plays a vital role in delivering effective cardiopulmonary resuscitation (CPR). Solevag et al. report that high-quality CC requires (A) optimal compression:ventilation (C:V) ratio, (B) adequate CC rate, (C) depth of CC as well as (D) full recoil between compressions 2. The American Heart Association (AHA) recommend delivering chest compressions on the lower third of the sternum to a depth of one third the anterior-posterior (AP) chest diameter. The recommended C:V ratio is 3:1 (90 compressions and 30 breaths per minute) 1.

A number of studies have highlighted the effects of rescuer fatigue on quality of chest compressions. One study reported adverse effects on CC quality when performed without interruption over a 3 minute period 6. It has therefore been recommended to rotate rescuers every 2-3 minutes in order to avoid rescuer fatigue and to ensure high quality CC6-7. As well as duration of CC, other factors can contribute to greater levels of rescuer fatigue. A number of studies have looked at the effect of different CC to ventilation methods on rescuer fatigue. Bodingh et al investigated this during simulated infant CPR. They reported greater levels of rescuer fatigue during simulated CPR in CCaV (continuous CC with asynchronous ventilation) at 120 CC per min compared to the recommended 3:1 C:V CPR 3. A similar study was performed by Li et al where rescuer fatigue was assessed during (i) 3:1 C:V ratio, (ii) CCaV at 90 CC per min and (iii) CCaV at 120 CC per min. However, unlike Bodingh et al, they found both 3:1 C:V and CCaV CPR to be equally fatiguing 4. Different CC techniques (TT vs TF method) can also cause varying levels of rescuer fatigue. In a recent study, Jiang et al compared the TT and TF chest compression techniques on infant mannequins and found that the TF method caused greater levels of rescuer fatigue compared with the TT method 5. We therefore set out to investigate whether different CC techniques cause different levels of rescuer fatigue during neonatal CPR. We hypothesize that performing TF method on neonatal mannequins will produce greater levels of rescuer fatigue. The results of this study would have significant implications in terms of choice of CC technique in new-born resuscitation.

The purpose of this study is to compare rescuer fatigue during simulated neonatal chest compressions using two different CC methods; the two-finger (TF) method vs two-thumb (TT) method. This will be performed on both preterm and term mannequins by neonatologists and level of fatigue will be assessed by measuring change in cardiac output during chest compressions.

Hypothesis: Performing CC using the two-finger (TF) method produces higher levels of rescuer fatigue compared with the two-thumb (TT) method during 5 minutes of simulated neonatal CPR.