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Background: Patients in prehospital care, irrespective of diseases or trauma might experience thermal discomfort because of a cold environment and are at risk for decreasing body temperature which can increase both morbidity and mortality.

Objective: To explore patients' experiences of being cold when injured in a cold environment.

Method: Twenty persons who had been injured in a cold environment in northern Sweden were interviewed. Active heat supply was given to 13 of them and seven had passive heat supply. The participants were asked to narrate their individual experience of cold and the pre- and post-injury event, until arrival at the emergency department. The interviews were transcribed verbatim, then analyzed with qualitative content analysis.

Results: Patients described that they suffered more from the cold than because of the pain from the injury. Patients who received active heat supply experienced it in a positive way. Two categories were formulated: Enduring suffering and Relief of suffering.

Conclusion: Thermal discomfort became the largest problem independent of the severity of the injuries. We recommend the use of active heat supply to reduce the negative experiences of thermal discomfort when a person is injured in a cold environment.

BACKGROUND: Exposure to cold temperatures is often a neglected problem in prehospital care. Cold exposure increase thermal discomfort and, if untreated causes disturbances of vital body functions until ultimately reaching hypothermia. It may also impair cognitive function, increase pain and contribute to fear and an overall sense of dissatisfaction. The aim of this study was to investigate injured and ill patients' experiences of cold exposure and to identify related factors.

METHOD: During January to March 2011, 62 consecutively selected patients were observed when they were cared for by ambulance nursing staff in prehospital care in the north of Sweden. The field study was based on observations, questions about thermal discomfort and temperature measurements (mattress air and patients' finger temperature). Based on the observation protocol the participants were divided into two groups, one group that stated it was cold in the patient compartment in the ambulance and another group that did not. Continuous variables were analyzed with independent sample t-test, paired sample t-test and dichotomous variables with cross tabulation.

RESULTS: In the ambulance 85% of the patients had a finger temperature below comfort zone and 44% experienced the ambient temperature in the patient compartment in the ambulance to be cold. There was a significant decrease in finger temperature from the first measurement indoor compared to measurement in the ambulance. The mattress temperature at the ambulance ranged from -22.3°C to 8.4°C.

CONCLUSION: Cold exposure in winter time is common in prehospital care. Sick and injured patients immediately react to cold exposure with decreasing finger temperature and experience of discomfort from cold. Keeping the patient in the comfort zone is of great importance. Further studies are needed to increase knowledge which can be a base for implications in prehospital care for patients who probably already suffer for other reasons.

Background:

Exposure to cold temperatures is, often, a neglected problem in prehospital care. One of the leading influences of the overall sensation of cold discomfort is the cooling of the back. The aim of this study was to evaluate the effect of a heated ambulance mattress-prototype on body temperatures and thermal comfort in an experimental study.

Method: Data were collected during four days in November, 2011 inside and outside of a cold chamber. All participants (n = 23) participated in two trials each. In one trial, they were lying on a stretcher with a supplied heated mattress and in the other trial without a heated mattress. Outcomes were back temperature, finger temperature, core body temperature, Cold Discomfort Scale (CDS), four statements from the state-trait anxiety - inventory (STAI), and short notes of their experiences of the two mattresses. Data were analysed both quantitatively and qualitatively. A repeated measure design was used to evaluate the effect of the two mattresses.

Results:

A statistical difference between the regular mattress and the heated mattress was found in the back temperature. In the heated mattress trial, the statement "I am tense" was fewer whereas the statements "I feel comfortable", "I am relaxed" and "I feel content" were higher in the heated mattress trial. The qualitative analyses of the short notes showed that the heated mattress, when compared to the unheated mattress, was experienced as warm, comfortable, providing security and was easier to relax on.

Conclusions:

Heat supply from underneath the body results in increased comfort and may prevent hypothermia which is important for injured and sick patients in ambulance care.

Background: The ambulance milieu does not offer good thermal comfort to patients during the cold Swedish winters. Patients’ exposure to cold temperatures combined with a cold ambulance mattress seems to be a major factor leading to an overall sensation of discomfort. As far as we have seen, there is still little research on the effect of active heat delivered from underneath in ambulance care. Therefore, the aim of this study was to evaluate the effect of an electrically heated ambulance mattress-prototype on thermal comfort and patients’ temperatures in the prehospital emergency care.

Methods:

A quantitative intervention study conducted in ambulance care in the north of Sweden. The ambulance used for the intervention group (n=30) was equipped with a heated mattress on the stretcher compared to the control group (n=30) where no active heat was provided on the stretcher. Outcome variables were measured as thermal comfort on the Cold Discomfort Scale (CDS), finger, ear, and air temperatures along with subjective comments on cold experiences.

Results:

Thermal comfort, measured by CDS, was improved during the ambulance transport to the Emergency Department (ED) in the intervention group (p= 0.001) but decreased in the control group (p=<0.014). A significant higher proportion (57%) of the control group rated the stretcher as cold to lie down on compared to three percent in the intervention group (p<0.001). Concerning finger, ear, and compartment air temperature no significant difference between groups was found. Mean transport time was approximately 15 minutes.

Conclusion:

The use of active heat, from underneath, increases the patients’ thermal comfort and may prevent the negative consequences of cold stress.