Pulmonary ventilation and respiratory gas exchange during manual artificial respiration and expired-air resuscitation on apnoeic normal adults. A comparison of the Holger Nielsen method and the mouth-to-mouth method.

Abstract

SUMMARY Comparative experimental studies on resuscitation by the mouth‐to‐mouth and Holger Nielsen (back‐pressure arm‐lift) methods are reported. The experiments were performed on five normal unconscious apnoeic adults and extended over periods of from 20 to 40 minutes. Tidal air, minute volume and alveolar ventilation/min. were determined pneumographically and/or spirometrically and/or volumetrically. The oxygen saturation and carbon dioxide tension of the arterial blood were determined during the experiments. Sufficient alveolar ventilation with normal arterial oxygen saturation and PCO2 was obtained by the mouth‐to‐mouth method in four out of five cases. In one case, hypoventilation occurred during the performance of the mouth‐to‐mouth method. Sufficient alveolar ventilation with normal arterial oxygen saturation and constant PCO2 was obtained by the Holger Nielsen method in one out of five cases. In four cases, variable degrees of hypoventilation occurred during the performance of the manual manoeuvres with an increase in the PCO2 of the arterial blood. However, an arterial oxygen saturation of more than 80% was maintained throughout the experimental period (30–40 minutes), although resuscitation with atmospheric air was given during the greater part of the period. The advantages and disadvantages of the two methods are discussed. Maintenance of a patent airway during artificial respiration must be considered to constitute a conditio sine qua non. If the Holger Nielsen method is to produce sufficient alveolar ventilation in the field, the respiratory frequency must be 15–16 breaths per minute, and the victim's head should be bent backwards (extension in the atlanto‐occipital joint). The authors are unable to recommend one of the two methods as being superior to the other in adults, but agree with the American investigators in their recommendation of the mouth‐to‐mouth method in infants and small children. The view is expressed that it would be desirable to train the general population as “two‐method” resuscitation operators.