IntroductionFever is frequently observed in critically ill patients. An independent association of fever with increased mortality has been observed in non-neurological critically ill patients with mixed febrile etiology. The association of fever and antipyretics with mortality, however, may be different between infective and non-infective illness.MethodsWe designed a prospective observational study to investigate the independent association of fever and the use of antipyretic treatments with mortality in critically ill patients with and without sepsis. We included 1,425 consecutive adult critically ill patients (without neurological injury) requiring > 48 hours intensive care admitted in 25 ICUs. We recorded four-hourly body temperature and all antipyretic treatments until ICU discharge or 28 days after ICU admission, whichever occurred first. For septic and non-septic patients, we separately assessed the association of maximum body temperature during ICU stay (MAXICU) and the use of antipyretic treatments with 28-day mortality.ResultsWe recorded body temperature 63,441 times. Antipyretic treatment was given 4,863 times to 737 patients (51.7%). We found that treatment with non-steroidal anti-inflammatory drugs (NSAIDs) or acetaminophen independently increased 28-day mortality for septic patients (adjusted odds ratio: NSAIDs: 2.61, P = 0.028, acetaminophen: 2.05, P = 0.01), but not for non-septic patients (adjusted odds ratio: NSAIDs: 0.22, P = 0.15, acetaminophen: 0.58, P = 0.63). Application of physical cooling did not associate with mortality in either group. Relative to the reference range (MAXICU 36.5°C to 37.4°C), MAXICU ≥ 39.5°C increased risk of 28-day mortality in septic patients (adjusted odds ratio 8.14, P = 0.01), but not in non-septic patients (adjusted odds ratio 0.47, P = 0.11).ConclusionsIn non-septic patients, high fever (≥ 39.5°C) independently associated with mortality, without association of administration of NSAIDs or acetaminophen with mortality. In contrast, in septic patients, administration of NSAIDs or acetaminophen independently associated with 28-day mortality, without association of fever with mortality. These findings suggest that fever and antipyretics may have different biological or clinical or both implications for patients with and without sepsis.Trial registrationClinicalTrials.gov: NCT00940654

I-gel may have a similar airway sealing to that of pLMA, higher than that of cLMA, and is not associated with adverse events. The I-gel might be an effective alternative as a supraglottic airway device.

We examined the effects of repeated artificial CO(2) (1,000 ppm) bathing on tympanic temperature (T(ty)), cutaneous blood flow, and thermal sensation in six healthy males. Each subject was immersed in CO(2)-rich water at a temperature of 34 degrees C up to the level of the diaphragm for 20 min. The CO(2)-rich water was prepared using a multi-layered composite hollow-fiber membrane. The CO(2) bathing was performed consecutively for 5 days. As a control study, subjects bathed in fresh water at 34 degrees C under the same conditions. T(ty) was significantly lowered during CO(2) bathing (P < 0.05). Cutaneous blood flow in the immersed skin (right forearm) was significantly increased during CO(2) bathing compared with that during fresh-water bathing (P < 0.05), whereas cutaneous blood flow in the non-immersed skin (chest) was not different between CO(2) and fresh-water bathing. Subjects reported a "warm" sensation during the CO(2) bathing, whereas they reported a "neutral" sensation during the fresh-water bathing. The effects of the repeated CO(2) bathing were not obvious for core temperature and cutaneous blood flow, but the thermal sensation score during the CO(2) bathing was reduced sequentially by repeated CO(2) bathing (P < 0.05). These thermal effects of CO(2) bathing could be ascribed largely to the direct action of CO(2) on vascular smooth muscles and to the activity of thermoreceptors in the skin. Serial CO(2) bathing may influence the activity of thermoreceptors in the skin.