Effects of kneeling posture on chest compression during cardiopulmonary resuscitation in males

To study the effects of kneeling posture on chest compression during cardiopulmonary resuscitation (CPR) in males.

Efficiency of chest compression during CPR affected millions of victims over the world. There are still no clear guidelines on kneeling posture that a rescuer should adopt in performing CPR.

A self-controlled repeated-measures design was applied in this study. The efficiency of chest compression on a mannequin when three kneeling postures were adopted (farthest, self-adjusted and nearest) was analysed.

Eighteen participants with qualified first-aid certificate were recruited. Each participant had to perform three sessions of CPR, using one of the three different kneeling postures (i.e., farthest, self-adjusted and nearest) in each. They were performed in a random order chosen by drawing lots. Each session consisted of five cycles of CPR in each kneeling posture. Each cycle consisted of 30 strokes of chest compression performed within 18 s with a 4-s pause between consecutive cycles. Each session lasted for 2 min. The participants were allowed to rest for 10 min on a chair between sessions. Efficiency of chest compression was quantified by compression force, joint angle, heart rate and energy expenditure. After each session of CPR, the participants were surveyed about their rate of perceived exertion.

Efficiency of chest compression in self-adjusted and nearest kneeling postures was significantly better than that of the farthest one. While the self-adjusted and nearest postures had the similar effect, most of the participants preferred self-adjusted kneeling posture because of lower rate of perceived exertion.

The use of the self-adjusted and nearest kneeling postures during CPR in males resulted in more effective chest compression with lower perceived exertion, compared with the farthest kneeling posture. Both these positions can be objectively recommended to enhance the efficiency of chest compression and thereby increase the cardiac arrest survival rate.

More consistent force and higher endurance could be achieved by performing CPR at self-adjusted kneeling posture.