[Efficacy of a novel warming blanket: prospective randomized trial]

Construction and application of composite insulation scheme in the perioperative period of patients undergoing laparoscopic colorectal cancer surgery

BACKGROUND

Elderly patients undergoing laparoscopic colorectal cancer surgery are at high risk for hypothermia-related complications. This study explores the efficacy of perioperative composite insulation interventions in maintaining normothermia and reducing postoperative risks in this vulnerable group.

AIM

To evaluate the efficacy of perioperative composite insulation in older patients undergoing colorectal cancer surgery.

METHODS

We selected 100 older patients who underwent laparoscopic surgery for colorectal cancer at Huzhou Central Hospital from September 2023 to April 2024. Using a random number table, patients were divided into a control group and intervention group of 50 patients each. After returning to the regular ward, the conventional group received traditional insulation intervention measures, while the intervention group received composite insulation nursing intervention. We observed and recorded postoperative blood pressure and heart rate changes, as well as postoperative anesthesia recovery time and incidence of complications.

RESULTS

The statistical results showed significant differences (P < 0.05) in heart rate changes and systolic blood pressure between the two groups. There was a significant change in heart rate between the groups immediately after surgery and at 15 and 30 minutes after surgery (P < 0.05). The heart rate and systolic blood pressure of the intervention group were significantly lower than those of the control group at 15 and 30 minutes after surgery (P < 0.05). The rewarming time of the intervention group was shorter than that of the control group, and the overall incidence of postoperative complications was significantly lower than that of the control group (P < 0.05).

CONCLUSION

For elderly patients undergoing laparoscopic colorectal cancer surgery, a composite insulation intervention during the perioperative period can maintain body temperature, reduce postoperative stress, and significantly reduce the incidence of hypothermia and related complications.

New Concept Air Conditioning System for the Operating Room to Minimize Patient Cooling and Surgeon Heating: A Historical Control Cohort Study

BACKGROUND

Intraoperative hypothermia is a common adverse event. For avoiding the complication due to hypothermia, many warming devices and methods have been used in perioperative period. It has been reported that more patients undergoing laparoscopic surgery tend to have hypothermia than with open surgery. To avoid intraoperative hypothermia, many kinds of warming tools have been used. But, it was also reported that some warming methods increased perceptions of distraction and physical demand.

METHODS

To achieve both patients' normothermia and surgeons' comfort, new air conditioning (AC) system was designed with considering the characteristics of laparoscopic surgery. The temperature of the airflows to the patient and to the surgeons can be adjusted independently in this new system. The new system has two parts. One controls the temperature of the central area over the operation table. The air from this part falls on the patients. The other part is the lateral area beside the operating table; the air from this part falls on the surgeons. The subjects of this study were 160 gastric cancer patients and 316 colorectal cancer patients undergoing laparoscopic surgery. The temperature of the central flow was set 23.5 °C, and the temperature of the lateral flow was set 22 °C just after the anesthesia. The number of timepoints the patient spent in hypothermic state, defined as a temperature cooler by 0.5 °C or more than that at the starting point of surgery, was determined in each patient.

RESULTS

In the results, the rate of hypothermic state in old operation rooms was 23.8% and that in new operation rooms was 2.7% in male gastric cancer patients (p < 0.01). And those were 37.1% in old operation rooms and 0.9% in new operation rooms in female gastric cancer patients (p < 0.01). The rate of hypothermic state in old operation rooms was 30.0% and that in new operation rooms was 9.5% in male colorectal cancer patients (p < 0.01). And those were 41.6% in old operation rooms and 8.9% in new operation rooms in female colorectal cancer patients (p < 0.01). The similar results were showed in the study, which subjects were limited the patients undergoing surgery in 2015 and 2016; which were the last year the old operation rooms were used and the first year the new operation rooms were used.

CONCLUSIONS

Thus, the usefulness of the new air conditioning system for achieving both patients' normothermia and comfort of surgeons could be verified in this study.

Preventing hypothermia in outpatient plastic surgery by self-warming or forced-air-warming blanket: A randomised controlled trial

BACKGROUND

In our outpatient post anaesthesia unit patients reported that they were feeling cold with or without shivering. Anaesthetic agents cause reduced thermoregulation, initially by redistribution of blood flow from core to periphery, later by negative balance between thermogenesis and heat loss. Even mild peri-operative hypothermia increases the risk of surgical wound infections, bleeding, impaired cardiac function, shivering, and decreases comfort.

OBJECTIVE(S)

We aimed to evaluate which of our current active warming measures, self-warming blanket or forced-air-warming blanket, were most effective in preventing inadvertent intraoperative heat loss. Secondarily, we assessed whether they prevented inadvertent peri-operative hypothermia when defined as core body temperature below 36 °C.

DESIGN

Randomised controlled trial, parallel group design.

SETTING

Aleris Solsiden hospital for outpatient surgery, Trondheim, Norway, from March to June 2016.

PATIENTS

A total of 112 consecutive patients planned for outpatient plastic surgery. Reasons for noninclusion: failing to meet the criteria for outpatient surgery according to the standard of the national society of anaesthesiology.

INTERVENTION(S)

Patients were randomised to active warming by a self-warming blanket or a forced-air-warming blanket. All patients received routine measures to prevent hypothermia with a high temperature in the operation theatres, prewarmed fluids, cotton blankets and surgical draping outside the surgical field.

MAIN OUTCOMES

Temperature, measured pre-operatively, every 10 min during general anaesthesia and postoperatively with a zero-heat-flux temperature sensor.

RESULTS

Core temperature was significantly lower in the self-warming blanket compared with the forced-air-warming blanket group during anaesthesia, P less than 0.0001. Hypothermia (<36 °C) was recorded in 47%, n = 22, patients in the self-warming blanket group and 25%, n = 16, in the forced-air-warming blanket group during the registration period, P = 0.02.

CONCLUSION

An underbody forced-air-warming blanket reduced heat loss to a greater extent than a self-warming blanket. But none of the interventions were sufficient to prevent inadvertent peri-operative hypothermia.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03163563.

Consensus Review of Optimal Perioperative Care in Breast Reconstruction: Enhanced Recovery after Surgery (ERAS) Society Recommendations

BACKGROUND

Enhanced recovery following surgery can be achieved through the introduction of evidence-based perioperative maneuvers. This review aims to present a consensus for optimal perioperative management of patients undergoing breast reconstructive surgery and to provide evidence-based recommendations for an enhanced perioperative protocol.

METHODS

A systematic review of meta-analyses, randomized controlled trials, and large prospective cohorts was conducted for each protocol element. Smaller prospective cohorts and retrospective cohorts were considered only when higher level evidence was unavailable. The available literature was graded by an international panel of experts in breast reconstructive surgery and used to form consensus recommendations for each topic. Each recommendation was graded following a consensus discussion among the expert panel. Development of these recommendations was endorsed by the Enhanced Recovery after Surgery Society.

RESULTS

High-quality randomized controlled trial data in patients undergoing breast reconstruction informed some of the recommendations; however, for most items, data from lower level studies in the population of interest were considered along with extrapolated data from high-quality studies in non-breast reconstruction populations. Recommendations were developed for a total of 18 unique enhanced recovery after surgery items and are discussed in the article. Key recommendations support use of opioid-sparing perioperative medications, minimal preoperative fasting and early feeding, use of anesthetic techniques that decrease postoperative nausea and vomiting and pain, use of measures to prevent intraoperative hypothermia, and support of early mobilization after surgery.

CONCLUSION

Based on the best available evidence for each topic, a consensus review of optimal perioperative care for patients undergoing breast reconstruction is presented.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

Forced-Air Warming for Rewarming and Comfort Following Laparoscopy: A Randomized Controlled Trail

We investigated the efficacy of a forced-air warming (FAW) system on postoperative rewarming and comfort in patients undergoing laparoscopic surgery. In this randomized controlled trial, a total of 127 participants were randomly divided into the FAW group ( n = 64) and control group ( n = 63). The esophageal temperature was measured every 30 min during surgery, and the tympanic temperature and comfort levels were measured preoperatively and in the postanesthesia care unit (PACU). Data analysis used the generalized estimating equation. We found that there was a lower incidence of postoperative hypothermia in the FAW group compared with the control group, as well as a higher body temperature between 30 and 180 min in the PACU, a shorter time for rewarming, and a higher comfort level. Taken together, these results suggest that FAW is an effective rewarming technique for laparoscopic patients during surgery and in the PACU that improves comfort levels.

Active perioperative patient warming using a self-warming blanket (BARRIER EasyWarm) is superior to passive thermal insulation: a multinational, multicenter, randomized trial

STUDY OBJECTIVE

Incidence of inadvertent perioperative hypothermia is still high; therefore, present guidelines advocate "prewarming" for its prevention. Prewarming means preoperative patient skin warming, which minimizes redistribution hypothermia caused by induction of anesthesia. In this study, we compared the new self-warming BARRIER EasyWarm blanket with passive thermal insulation regarding mean perioperative patient core body temperature.

DESIGN

Multinational, multicenter randomized prospective open-label controlled trial.

SETTING

Surgical ward, operation room, postanesthesia care unit at 4 European hospitals.

PATIENTS

A total of 246 adult patients, American Society of Anesthesiologists class I to III undergoing elective orthopedic; gynecologic; or ear, nose, and throat surgery scheduled for 30 to 120 minutes under general anesthesia.

INTERVENTIONS

Patients received warmed hospital cotton blankets (passive thermal insulation, control group) or BARRIER EasyWarm blanket at least 30 minutes before induction of general anesthesia and throughout the perioperative period (intervention group).

MEASUREMENTS

The primary efficacy outcome was the perioperative mean core body temperature measured by a tympanic infrared thermometer. Secondary outcomes were hypothermia incidence, change in core body temperature, length of stay in postanesthesia care unit, thermal comfort, patient satisfaction, ease of use, and adverse events related to the BARRIER EasyWarm blanket.

MAIN RESULTS

The BARRIER EasyWarm blanket significantly improved perioperative core body temperature compared with standard hospital blankets (36.5°C, SD 0.4°C, vs 36.3, SD 0.3°C; P<.001). Intraoperatively, in the intervention group, hypothermia incidence was 38% compared with 60% in the control group (P=.001). Postoperatively, the figures were 24% vs 49%, respectively (P=.001). Patients in the intervention group had significantly higher thermal comfort scores, preoperatively and postoperatively. No serious adverse effects were observed in either group.

CONCLUSIONS

Perioperative use of the new self-warming blanket improves mean perioperative core body temperature, reduces the incidence of inadvertent perioperative hypothermia, and improves patients' thermal comfort during elective adult surgery.

Unexpectedly high incidence of hypothermia before induction of anesthesia in elective surgical patients

STUDY OBJECTIVE

Perioperative hypothermia is a frequently observed phenomenon of general anesthesia and is associated with adverse patient outcome. Recently, a significant influence of core temperature before induction of anesthesia has been reported. However, there are still little existing data on core temperature before induction of anesthesia and no data regarding potential risk factors for developing preoperative hypothermia. The purpose of this investigation was to estimate the incidence of hypothermia before anesthesia and to determine if certain factors predict its incidence.

DESIGN/SETTING/PATIENTS

Data from 7 prospective studies investigating core temperature previously initiated at our department were analyzed. Patients undergoing a variety of elective surgical procedures were included.

INTERVENTIONS/MEASUREMENTS

Core temperature was measured before induction of anesthesia with an oral (314 patients), infrared tympanic (143 patients), or tympanic contact thermometer (36 patients). Available potential predictors included American Society of Anesthesiologists status, sex, age, weight, height, body mass index, adipose ratio, and lean body weight. Association with preoperative hypothermia was assessed separately for each predictor using logistic regression. Independent predictors were identified using multivariable logistic regression.

MAIN RESULTS

A total of 493 patients were included in the study. Hypothermia was found in 105 patients (21.3%; 95% confidence interval, 17.8%-25.2%). The median core temperature was 36.3°C (25th-75th percentiles, 36.0°C-36.7°C). Two independent factors for preoperative hypothermia were identified: male sex and age (>52years).

CONCLUSIONS

As a consequence of the high incidence of hypothermia before anesthesia, measuring core temperature should be mandatory 60 to 120minutes before induction to identify and provide adequate treatment to hypothermic patients.

Thermal insulation for preventing inadvertent perioperative hypothermia

BACKGROUND

Inadvertent perioperative hypothermia occurs because of interference with normal temperature regulation by anaesthetic drugs and exposure of skin for prolonged periods. A number of different interventions have been proposed to maintain body temperature by reducing heat loss. Thermal insulation, such as extra layers of insulating material or reflective blankets, should reduce heat loss through convection and radiation and potentially help avoid hypothermia.

OBJECTIVES

To assess the effects of pre- or intraoperative thermal insulation, or both, in preventing perioperative hypothermia and its complications during surgery in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 2), MEDLINE, OvidSP (1956 to 4 February 2014), EMBASE, OvidSP (1982 to 4 February 2014), ISI Web of Science (1950 to 4 February 2014), and CINAHL, EBSCOhost (1980 to 4 February 2014), and reference lists of articles. We also searched Current Controlled Trials and ClinicalTrials.gov.

SELECTION CRITERIA

Randomized controlled trials of thermal insulation compared to standard care or other interventions aiming to maintain normothermia.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and assessed risk of bias for each included study, with a third author checking details. We contacted some authors to ask for additional details. We only collected adverse events if reported in the trials.

MAIN RESULTS

We included 22 trials, with 16 trials providing data for some analyses. The trials varied widely in the type of patients and operations, the timing and measurement of temperature, and particularly in the types of co-interventions used. The risk of bias was largely unclear, but with a high risk of performance bias in most studies and a low risk of attrition bias. The largest comparison of extra insulation versus standard care had five trials with 353 patients at the end of surgery and showed a weighted mean difference (WMD) of 0.12 ºC (95% CI -0.07 to 0.31; low quality evidence). Comparing extra insulation with forced air warming at the end of surgery gave a WMD of -0.67 ºC (95% CI -0.95 to -0.39; very low quality evidence) indicating a higher temperature with forced air warming. Major cardiovascular outcomes were not reported and so were not analysed. There were no clear effects on bleeding, shivering or length of stay in post-anaesthetic care for either comparison. No other adverse effects were reported.

AUTHORS' CONCLUSIONS

There is no clear benefit of extra thermal insulation compared with standard care. Forced air warming does seem to maintain core temperature better than extra thermal insulation, by between 0.5 ºC and 1 ºC, but the clinical importance of this difference is unclear.

[Prewarming. Yesterday's luxury, today's minimum requirement]

Prewarming is a useful and effective measure to reduce perioperative hypothermia. Due to §23(3) of the German Infektionsschutzgesetz (Gesetz zur Verhütung und Bekämpfung von Infektionskrankheiten beim Menschen, Infection Act, act on protection and prevention of infectious diseases in man) and the recommendations of the Hospital Hygiene and Infection Prevention Committee of the Robert Koch Institute, implementation of prewarming is clearly recommended. There are several technically satisfactory and practicable devices available allowing prewarming on the normal hospital ward, in the preoperative holding area or in the induction room of the operating theater (OR) The implementation of prewarming requires additional equipment and training of staff. Using a locally adapted concept for the implementation of prewarming does not lead to inefficiency in the perioperative process. In contrast, the implementation can help to achieve stable arrival times for patients in the OR.