Comparison of two warming interventions in surgical patients with mild and moderate hypothermia

Two interventions: a forced warm-air device (Bair-Hugger series 500, Augustine Medical Inc., Eden Prairie, MN, USA), group 1; and a standardized approach to the use of warmed blankets (group 2) are compared with the aim of enhancing thermoregulation in surgical patients with mild and moderate hypothermia in the immediate recovery period. One hundred and twenty patients in a post-anaesthetic care unit were systematically allocated to group 1 or group 2 so each group consisted of 110 participants. No significant differences were found between the groups in gender, age, time in surgery, use of warmed intravenous fluids or muscle relaxants, or type of surgery. After exclusion of orthopaedic patients, significant differences in the mean rewarming rates were found, with more rapid rewarming occurring within group 1 (the group rewarmed with a forced warm-air device, t = 2.15, df = 92, P = 0.03) compared with group 2. No significant differences were found in the mean rewarming time, or heat gain between groups, and subsequent power estimates were less than 0.80. This study supports improved rewarming rates in select surgical patients (with mild or moderate hypothermia) using the Bair-Hugger^TM compared with a standardized blanket rewarming intervention and identifies the need for patient comfort and cost-benefit analysis to be considered in future studies.     

Frequency of Aspirating Gastric Tubes for Patients Receiving Enteral Nutrition in the ICU

Background: Enteral nutrition (EN) tolerance is often monitored by aspirating stomach contents by syringe at prescribed intervals. No studies have been conducted to assess the most appropriate time interval for aspirating gastric tubes. We compared gastric tube aspirations every 4 hours (usual care) with a variable regimen (up to every 8 hours aspirations). Methods: This randomized controlled trial (RCT) enrolled patients who stayed in the intensive care unit (ICU) for >48 hours, had a gastric tube, and were likely to receive EN for 3 or more days. Patients were randomized (computer‐generated randomization) to either the control (every 4 hours) or intervention group (variable regimen). The primary outcome was number of gastric tube aspirations per day from randomization until EN was ceased or up to 2 weeks postrandomization. Results: Following Institutional Ethics Committee approval, 357 patients were recruited (control group, n = 179; intervention group, n = 178). No differences were found in age, sex, worst APACHE II score, or time to start of EN. In the intention‐to‐treat analysis, the intervention group had fewer tube aspirations per day (3.4 versus 5.4 in the control group, P < .001). Vomiting/regurgitation was increased in the intervention group (2.1% versus 3.6%, P = .02). There were no other differences in complications. Conclusion: This is the first RCT to examine the frequency of gastric tube aspirations. The frequency of gastric tube aspirations was reduced in the variable‐regimen group with no increase in risk to the patient. Reducing the frequency of aspirations saves nursing time, decreases risk of contamination of feeding circuit, and minimizes risk of body fluid exposure.     

Activated protein C prevents inflammation yet stimulates angiogenesis to promote cutaneous wound healing

Activated protein C (APC) is a serine protease that plays a central role in physiological anticoagulation, and has more recently been shown to be a potent anti-inflammatory mediator. Using cultured human cells, we show here that APC up-regulates the angiogenic promoters matrix metalloproteinase-2 in skin fibroblasts and umbilical vein endothelial cells, vascular endothelial growth factor in keratinocytes and fibroblasts, and monocyte chemoattractant protein-1 in fibroblasts. In the chick embryo chorioallantoic membrane assay, APC promoted the granulation/remodeling phases of wound healing by markedly stimulating angiogenesis as well as promoting reepithelialization. In a full-thickness rat skin-healing model, a single topical application of APC enhanced wound healing compared to saline control. APC-treated wounds had markedly more blood vessels on day 7 and a significantly lower infiltration of neutrophils at days 4 and 7. The broad spectrum matrix metallo-proteinase, GM6001, prevented the ability of APC to promote wound healing. In summary, our results show that APC promotes cutaneous wound healing via a complex mechanism involving stimulation of angiogenesis and inhibition of inflammation. These unique properties of APC make it an attractive therapeutic agent to promote the healing of chronic wounds.