Comparison of Electric Resistive Heating Pads and Forced-Air Warming for Pre-hospital Warming of Non-shivering Hypothermic Subjects.

INTRODUCTION: Victims of severe hypothermia require external rewarming, as self-rewarming through shivering heat production is either minimal or absent. The US Military commonly uses forced-air warming in field hospitals, but these systems require significant power (600-800 W) and are not portable. This study compared the rewarming effectiveness of an electric resistive heating pad system (requiring 80 W) to forced-air rewarming on cold subjects in whom shivering was pharmacologically inhibited. MATERIALS AND METHODS: Shivering was inhibited by intravenous meperidine (1.5 mg/kg), administered during the last 10 min of cold-water immersion. Subjects then exited from the cold water, were dried and lay on a rescue bag for 120 min in one of the following conditions: spontaneous rewarming only (rescue bag closed); electric resistive heating pads (EHP) wrapped from the anterior to posterior torso (rescue bag closed); or, forced-air warming (FAW) over the anterior surface of the body (rescue bag left open and cotton blanket draped over warming blanket). Supplemental meperidine (to a maximum cumulative dose of 3.3 mg/kg) was administered as required during rewarming to suppress shivering. RESULTS: Six healthy subjects (3 m, 3 f) were cooled on three different occasions, each in 8°C water to an average nadir core temperature of 34.4 ± 0.6°C (including afterdrop). There were no significant differences between core rewarming rates (spontaneous; 0.6 ± 0.3, FAW; 0.7 ± 0.2, RHP; 0.6 ± 0.2°C/h) or post-cooling afterdrop (spontaneous; 1.9 ± 0.4, FAW; 1.9 ± 0.3, RHP; 1.6 ± 0.2°C) in any of the 3 conditions. There were also no significant differences between metabolic heat production (S; 74 ± 20, FAW; 66 ± 12, RHP; 63 ± 9 W). Total heat gain was greater with FAW (36 W gain) than EHP (13 W gain) and spontaneous (13 W loss) warming (p < 0.005). CONCLUSIONS: Total heat gain was greater in FAW than both EHP, and spontaneous rewarming conditions, however, there were no observed differences found in rewarming rates, post-cooling afterdrop or metabolic heat production. The electric heat pad system provided similar rewarming performance to a forced-air warming system commonly used in US military field hospitals for hypothermic patients. A battery-powered version of this system would not only relieve pressure on the field hospital power supply but could also potentially allow extending use to locations closer to the field of operations and during transport. Such a system could be studied in larger groups in prospective trials on colder patients.

Use of fecal occult blood test in hospitalized patients: survey of physicians practicing in a large central Canadian health region and Canadian gastroenterologists.

BACKGROUND: Although the fecal occult blood test (FOBT) was developed for colorectal cancer screening in the outpatient setting, it continues to be used among hospitalized patients. No previous study has evaluated the knowledge, beliefs and attitudes of practicing physicians on the use of FOBT among hospitalized patients and compared practices among physicians with different medical specialty training. OBJECTIVE: To survey physicians in the Winnipeg Regional Health Authority (WRHA) and Canadian gastroenterologists (GIs) on the use of FOBT in hospitals. METHODS: A survey was distributed by e-mail to internists (n=198), emergency medicine (EM) physicians (n=118), general surgeons (n=47) and family medicine (FM) physicians with admitting privileges (n=29) in the WRHA. Canadian GIs were surveyed through the membership database of the Canadian Association of Gastroenterology (CAG) (n=449). The survey included items regarding demographics of the respondents and their current use of FOBT in hospitals. RESULTS: Response rates ranged from 18% among CAG members to 69% among FM physicians in the WRHA. General internal medicine, general surgeon and GI respondents were less likely to order a FOBT and less likely to believe that an FOBT was useful in assessing emergency room or hospitalized patients when compared with FM and EM respondents (P<0.001). The most common indications for ordering a FOBT were black stools and anemia with and without iron deficiency. Two-thirds of EM physicians preferred point-of-care testing rather than laboratory reporting of FOBT. CONCLUSIONS: The present survey suggests that FOBTs are commonly used in hospitals by EM and FM physicians for indications such as anemia and black stools.