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Objectives: Previous case series reported an association between dexmedetomidine use and hyperthermia. Temperature data have not been systematically reported in previous randomized controlled trials evaluating dexmedetomidine. A causal link between dexmedetomidine administration and elevated temperature has not been demonstrated.Design: Post hoc analysis.Setting: Four ICUs in Australia and New Zealand.Patients: About 703 mechanically ventilated ICU patients.Interventions: Early sedation with dexmedetomidine versus usual care.Measurements and Main Results: The primary outcome was mean daily body temperature. Secondary outcomes included the proportions of patients with body temperatures greater than or equal to 38.3°C and greater than or equal to 39°C, respectively. Outcomes were recorded for 5 days postrandomization in the ICU. The mean daily temperature was not different between the dexmedetomidine (n = 351) and usual care (n = 352) groups (36.84°C ± sd vs 36.78°C ± sd; p = 0.16). Over the first 5 ICU days, more dexmedetomidine group (vs usual care) patients had a temperature greater than or equal to 38.3°C (43.3% vs 32.7%, p = 0.004; absolute difference 10.6 percentage points) and greater than or equal to 39.0°C (19.4% vs 12.5%, p = 0.013; absolute difference 6.9 percentage points). Results were similar after adjusting for diagnosis, admitting temperature, age, weight, study site, sepsis occurrence, and the time from dexmedetomidine initiation to first hyperthermia recorded. There was a significant dose response relationship with temperature increasing by 0.30°C ±0.08 for every additional 1 μg/kg/hr of dexmedetomidine received p < 0.0002.Conclusions: Our study suggests potentially important elevations in body temperature are associated with early dexmedetomidine sedation, in adults who are mechanically ventilated in the ICU. [ABSTRACT FROM AUTHOR]

In cattle, genetic variation exists in regulation of body temperature and stabilization of cellular function during heat stress. There are opportunities to reduce the impact of heat stress on cattle production by identifying the causative mutations responsible for genetic variation in thermotolerance and transferring specific alleles that confer thermotolerance to breeds not adapted to hot climates. An example of a mutation conferring superior ability to regulate body temperature is the group of frame-sift mutations in the prolactin receptor gene (PRLR) that lead to a truncated receptor and development of cattle with a short, sleek hair coat. Slick mutations in PRLR have been found in several extant breeds derived from criollo cattle. The slick mutation in Senepol cattle has been introgressed into dairy cattle in Puerto Rico, Florida and New Zealand. An example of a mutation that confers cellular protection against elevated body temperature is a deletion mutation in the promoter region of a heat shock protein 70 gene called HSPA1L. Inheritance of the mutation results in amplification of the transcriptional response of HSPA1L to heat shock and increased cell survival. The case of PRLR provides a promising example of the efficacy of the genetic approach outlined in this paper. Identification of other mutations conferring thermotolerance at the whole-animal or cellular level will lead to additional opportunities for using genetic solutions to reduce the impact of heat stress. • Genetic variation exists in regulation of body temperature and stabilization of cellular function during heat stress. • There are opportunities to reduce the impact of heat stress on cattle production by transferring specific alleles that confer thermotolerance to breeds not adapted to hot climates. • One successful example of this approach is introgression of the slick mutation in PRLR from Senepol to dairy cattle. [ABSTRACT FROM AUTHOR]

Background: Peritonectomy and hyperthermic intraperitoneal chemotherapy (HIPEC) is used in specialised units outside of gynaecological cancer centres in Australia and New Zealand to treat advanced epithelial ovarian cancer (AEOC). There is significant equipoise toward this treatment by gynaecological oncologists (CGOs). Aims: To determine the attitudes and preferences of CGOs toward peritonectomy and HIPEC for the treatment of AEOC. Materials and Methods: A questionnaire was sent to all 53 CGOs in Australia and New Zealand asking their opinions about peritonectomy and HIPEC for the treatment of AEOC. Data collected included surgeon demographics, individual surgical practices, and willingness of CGOs to refer patients for peritonectomy or HIPEC. Potential factors influencing this decision were investigated using χ2 tests and logistic regression analysis. Results: Response rate was 89%. While 68% of CGOs would refer a patient for peritonectomy, most cases would be recurrent tumour of borderline or mucinous histology. Only 13% would refer a case of primary stage 3 EOC, even if predicting they cannot completely resect the tumour. This was due to concerns around morbidity and mortality, and a preference for neoadjuvant chemotherapy. In regard to HIPEC, 61% of CGOs were unsure about its use, due to reported lack of evidence, and potential morbidity. CGOs of female gender were more likely to recommend peritonectomy and HIPEC. Conclusions: CGOs would refer only selected cases of AEOC for peritonectomy or HIPEC, due to concerns around insufficient evidence, and potential morbidity. The results of large well‐conducted clinical trials will help determine the future of peritonectomy and HIPEC for the treatment of AEOC. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the effect of 7 days' supplementation with New Zealand blackcurrant extract on thermoregulation and substrate metabolism during running in the heat., Design: Randomized, double-blind, cross-over study., Methods: Twelve men and six women (mean±SD: Age 27±6 years, height 1.76±0.10m, mass 74±12kg, V̇O 2max 53.4±7.0mLkg -1 min -1 ) completed one assessment of maximal aerobic capacity and one familiarisation trial (18°C, 40% relative humidity, RH), before ingesting 2×300mgday -1 capsules of CurraNZ™ (each containing 105mg anthocyanin) or a visually matched placebo (2×300mg microcrystalline cellulose M102) for 7 days (washout 14 days). On day 7 of each supplementation period, participants completed 60min of fasted running at 65% V̇O 2max in hot ambient conditions (34°C and 40% relative humidity)., Results: Carbohydrate oxidation was decreased in the NZBC trial [by 0.24gmin -1 (95% CI: 0.21-0.27gmin -1 )] compared to placebo (p= 0.014, d=0.46), and fat oxidation was increased in the NZBC trial [by 0.12gmin -1 (95% CI: 0.10 to 0.15gmin -1 )], compared to placebo (p=0.008, d=0.57). NZBC did not influence heart rate (p=0.963), rectal temperature (p=0.380), skin temperature (p=0.955), body temperature (p=0.214) or physiological strain index (p=0.705) during exercise., Conclusions: Seven-days intake of 600mg NZBC extract increased fat oxidation without influencing cardiorespiratory or thermoregulatory variables during prolonged moderate intensity running in hot conditions., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)