Can body temperature be maintained during aeromedical transport?

Abstract

Background: Aeromedical transport in northern areas may be associated with hypothermia. The objective of this study was to determine whether significant hypothermia (core temperature <35ºC) occurs in severely injured or ill intubated patients during transport by rotary wing aircraft. Methods: In this prospective cohort study, all intubated patients over 16 years of age who were transported by rotary wing aircraft from rural hospitals or trauma scenes in northern Alberta to regional hospitals in Edmonton were eligible for study. Esophageal thermometers were used to measure core temperature at 10-minute intervals during transport. Results: Of 133 potentially eligible patients, 116 were enrolled; 69 (59%) had esophageal thermometers inserted, and 47 (41%) had other temperature measurements. Severe hypothermia occurred in only 1% to 2% of cases, but 28% to 39% of patients met criteria for mild hypothermia prior to transport. Core temperatures did not fall during transport, despite the fact that warming techniques were documented in only 38% of cases. Conclusions: During brief (<225 km) rotary wing aeromedical transport of severely injured or ill patients, significant hypothermia is uncommon and body temperature is generally well maintained with the use of simple passive measures. These findings do not justify recommendations for more aggressive core temperature monitoring during this type of aeromedical transport. RÉSUMÉ Contexte :Le transport aéromédical dans les régions nordiques peut être associé à l'hypothermie. La présente étude avait comme objectif de déterminer si une hypothermie importante (tempéra-ture centrale <35ºC) se manifeste chez des patients intubés gravement blessés ou malades lors du transport par aéronef à voilure tournante. Méthodes : Dans cette étude de cohorte prospective, tous les patients intubés âgés de plus de 16 ans qui avaient été transportés par aéronef à voilure tournante à partir d'hôpitaux ruraux ou de scènes de trauma dans la région du nord de l'Alberta vers des hôpitaux régionaux à Edmonton étaient admissibles à l'étude. On eut recours à des thermomètres oesophagiens pour prendre la température centrale à des intervalles de 10 minutes pendant le transport. Résultats : Parmi 133 patients potentiellement admissibles, 116 furent inclus dans l'étude; on inséra un thermomètre oesophagien chez 69 de ces patients (59 %) et on eut recours à d'autres

Temperature change in the helicopter transport of trauma patients

“…Watts et al found a reduction in temperature, 9 while Hatfield and Sookram reported no significant relationship between air transportation and temperature change. 10 Our subgroup of patients that did undergo heat loss are a cause for concern, mirroring the findings of Watts et al 9 The known benefits of centralized trauma care will continue to increase the demand for helicopter retrieval. Our results highlight the need to assess each patient's likelihood of hypothermia and use this as a prompt to optimize the patients' resuscitation before and during their transfer to definitive care.…”

When do trauma patients lose temperature? – a prospective observational study

“…Studies to date have reported adverse temperature changes in trauma patients during helicopter transfer. 27,28 If hypothermia is confirmed by the EMS, this should ideally trigger active rewarming already in the pre-hospital environment. This is an attractive option, as a transportation time of around 30 min can hardly be expected to be much shortened in the future.…”

“…Another six patients with ISS < 9 were subsequently excluded, leaving 22 patients (14 males and eight females) for the final analysis. Median age was 27 years (IQR 19-55), median ISS was 21 (IQR [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], and the median NISS was 25.5 (IQR 17-36). Three patients died prior to hospital discharge.…”

Body temperature change and outcomes in patients undergoing long-distance air medical transport

“…However, the flight duration in previous studies was relatively short (range, 18-35 min) [1][2][3][4]6]. Also, the evaluated outcome in previous studies was body temperature change between before and after air transport.…”

“…Air medical transport is common in emergency settings and is now the global standard. Although ambient air temperature decreases with altitude, several studies showed that the body temperature of most adult patients did not decline significantly during air medical transport [1][2][3][4][5][6]. Studies also show that body temperature change is not associated with flight duration [1,2,5,6] and outside air temperature [1][2][3][4].…”