Werner Beikircher

Electrical Heart Activity Recorded During Prolonged Avalanche Burial

A man in his midthirties triggered an avalanche at an elevation of 2750 m (9022 ft) while ski touring and sustained complete avalanche burial for 253 minutes before being located with an avalanche transceiver device, probed, and extricated by a rescue team. The burial depth (ie, depth of the head) was 30 cm (1 ft). The victim was in a supine position with a patent airway and a clearly visible air space in front of the mouth and nose with a size of 15×15×5 cm (0.5×0.5×0.2 ft) and frozen inner surface, which was not reported to the emergency physician on site. The victim had a Glasgow Coma Scale of 3 (E1V1M1), no vital signs, and no obvious traumatic fatal injuries. Extrication proceeded without reading the core body temperature or ECG. Because of severe weather conditions and the impending risk for the rescue team, the emergency physician withheld an on-site attempt of resuscitation. The victim was evacuated down to the valley by helicopter and declared dead. While the victims body was being handled in the mortuary, it was revealed that the victim was equipped with a multifunction sport watch and transmitter chest belt. The recorded dataset included heart rate, …

Retention of mouth-to-mouth, mouth-to-mask and mouth-to-face shield ventilation

Background: Retention of mouth-to-mouth, mouth-to-mask and mouth-to-face shield ventilation techniques is poorly understood. Methods: A prospective randomised clinical trial was undertaken in January 2004 in 70 candidates randomly assigned to training in mouth-to-mouth, mouth-to-mask or mouth-to-face shield ventilation. Each candidate was trained for 10 min, after which tidal volume, respiratory rate, minute volume, peak airway pressure and the presence or absence of stomach inflation were measured. 58 subjects were reassessed 1 year later and study parameters were recorded again. Data were analysed with ANOVA, χ2 and McNemar tests. Results: Tidal volume, minute volume, peak airway pressure, ventilation rate and stomach inflation rate increased significantly at reassessment with all ventilation techniques compared with the initial assessment. However, at reassessment, mean (SD) tidal volume (960 (446) vs 1008 (366) vs 1402 (302) ml; p<0.05), minute volume (12 (5) vs 13 (7) vs 18 (3) l/min; p<0.05), peak airway pressure (14 (8) vs 17 (13) vs 25 (8) cm H2O; p<0.05) and stomach inflation rate (63% vs 58% vs 100%; p<0.05) were significantly lower with mouth-to-mask and mouth-to-face shield ventilation than with mouth-to-mouth ventilation. The ventilation rate at reassessment did not differ significantly between the ventilation techniques. Conclusions: One year after a single episode of ventilation training, lay persons tended to hyperventilate; however, the degree of hyperventilation and resulting stomach inflation were lower when a mouth-to-mask or a face shield device was employed. Regular training is therefore required to retain ventilation skills; retention of skills may be better with ventilation devices.

Non-extracorporeal rewarming at a rate of 6.8 °C per hour in a deeply hypothermic arrested patient

A 86-year old man was found outside in ventricular fibrillation VF). Cardiopulmonary resuscitation (CPR) was initiated. Snow was alling (−7 ◦C); wind-speed was 12 km h−1. Deep hypothermia was iagnosed (22 ◦C epitympanically). Five shocks were delivered but F persisted. Upon arrival in the hospital 40 min later, core temperature oesophageally) was 22 ◦C. Transfer to a hospital with extracorpoeal rewarming (∼100 km distance) was impossible due to heavy nowfall. Thus, rewarming was started on site in the operating oom with peritoneal lavage (saline 40 ◦C) with a rapid infuion system (Level 1®, Smith Medical International Ltd., Herts, K) through two laparoscopic accesses. Additionally, external orced air rewarming was applied and warm intravenous infusions ere administered. Combining these techniques a rewarmingate of 6.8 ◦C h−1 was achieved. At a core temperature of 30 ◦C efibrillations were attempted every 2 min, 1 mg adrenaline was dministered every 6–10 min and 300 mg amiodarone was injected nce (Fig. 1). However, VF continued and CPR was terminated after 00 min at a core temperature of 35 ◦C. Accidental hypothermia is defined as a core temperature 35 ◦C.1 In deeply hypothermic arrested patients extracorporeal ewarming is considered the gold standard because survival may e 50–100% compared to ∼10% with traditional rewarming techiques such as peritoneal lavage.1,2 However, when transportation o an extracorporeal rewarming centre is not possible alternative ewarming methods may be required on site. Maintaining high quality chest compressions during nonxtracorporeal rewarming requires a high number of skilled staff; lternatively the use of a mechanical chest compression device may e helpful. In addition to active internal rewarming with peritoneal avage and warm infusions we used external rewarming with orced warm air to increase the rewarming rate. Forced air rewarmng per se is a simple and effective measure, rewarming rates of –3 ◦C h−1 have been reported.1 A considerable amount of warmed ntravenous fluids may be required to compensate for cold diuresisnduced dehydration and rewarming-induced vasodilation. Fluid equirements should be monitored closely because patients sucessfully resuscitated from hypothermia-induced cardiac arrest are rone to develop pulmonary oedema.1–4 In this patient we accessed the peritoneal cavity for active interal rewarming with lavage. Two trocars were inserted, one at the mbilicus for the laparoscopy camera and the second in the lower

Effects of training time and feedback on ventilation skills in lay rescuers

Objective Lay rescuers have difficulties acquiring ventilation skills during training. Non-feedback manikins are still widely employed, although skill acquisition is suboptimal. We analysed if a longer training time and verbal feedback, given by an instructor, improved ventilation skill acquisition with non-feedback manikins. Methods Forty-three high school students without prior medical training participated in this prospective randomised trial. Under one-to-one instructor guidance, 25 volunteers were trained on a manikin with a mouth-to-mask device for 10 min, and 18 volunteers for 20 min. After training, volunteers were assessed and verbal feedback was given: ventilate more if the mean tidal volume <0.5 L, ventilate less if >0.7 L or ventilate the same for 0.5–0.7 L. The volunteers were then reassessed. Results At the assessment, tidal volume, minute volume, peak airway pressure, ventilation rate and stomach inflation rate were comparable between the 10 and 20 min groups. After verbal feedback, at reassessment both groups increased tidal volume (assessment 0.75±0.24 vs reassessment 0.80±0.16 l/min; p=0.007), minute volume (9.1±3.0 vs 10.0±2.4 l/min; p=0.001), peak airway pressure (17.0±5.2 vs 18.3±3.4 cmH2O; p=0.003) and stomach inflation rate (67 vs 88%; p=0.02), while ventilation rate (12.3±2.1 vs 12.6±2.3 ventilations/min; p=NS) remained comparable. Conclusions Both 10 and 20 min ventilation training times resulted in comparable skills. Volunteers hyperventilated the manikin and produced excessive stomach inflation in this model. This increased even further after verbal feedback.

Response to Letter Regarding Article, “Electrical Heart Activity Recorded During Prolonged Avalanche Burial”

We thank Pettit et al for their comments on our article on electrical heart activity recorded during prolonged avalanche burial.1 They raised concerns about the accuracy of the recorded data, attributing phases of constant frequency to artifact. To address potential technical failure of the device, several tests were performed directly after the accident and additional details were verified. First, the victim was found fully dressed in …