Effect of Preoperative Forced-Air Warming on Postoperative Temperature and Postanesthesia Care Unit Length of Stay

Barriers and facilitators to evidence-based perioperative hypothermia management for orthopaedic patients: A systematic review

AIM

To assess barriers and facilitators to the implementation of guidelines for the prevention of inadvertent perioperative hypothermia in orthopaedic patients.

DESIGN

Systematic review.

DATA SOURCES

Nine databases: PubMed, Embase, CINAHL, Cochrane CENTRAL, PsycINFO, ProQuest Dissertations and Theses, Scopus, Web of Science and Trip Clinical Evidence Database.

METHODS

Primary studies published in English between January 2008 to July 2022 were screened. Study selection, quality assessment, and data extraction were completed independently by researchers. Data were extracted using the Consolidated Framework for Implementation Research and mapped to the Expert Recommendations for Implementing Change strategies.

RESULTS

Eighty-seven studies were included in the review. The most frequently reported barriers and facilitators related to evidence strength, relative advantage, and cost of implementing perioperative hypothermia prevention guidelines. The top four ERIC strategies were: Identify and prepare champions; Conduct educational meetings; Assess for readiness and identify barriers and facilitators; and Inform local opinion leaders.

CONCLUSION

This review provides synthesized evidence regarding barriers and facilitators to perioperative hypothermia guidelines for patients undergoing orthopaedic surgery.

IMPLICATIONS FOR THE PROFESSION AND PATIENT CARE

Our work provides theory guided strategies to promote implementation of perioperative hypothermia prevention to assist nurses caring for patients undergoing orthopaedic surgery.

IMPACT

Findings provide professionals caring for patients undergoing orthopaedic surgery with theory-informed strategies to improve perioperative hypothermia prevention. Reducing perioperative hypothermia will improve outcomes for patients undergoing orthopaedic surgery.

REPORTING METHOD

The review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020.

NO PATIENT OR PUBLIC CONSULTATION

Due to the study design, no patient or public consultation took place.

The Effect of Prewarming on Perioperative Hypothermia: A Systematic Review and Meta-analysis of Randomized Controlled Studies

PURPOSE

One of the methods for maintaining perioperative normothermia is prewarming. This study was conducted to investigate the effect of a preoperative prewarming intervention on perioperative body temperature.

DESIGN

Systematic review and meta-analysis.

METHODS

A literature review was conducted using PubMed, CINAHL, Cochrane Central, Science Direct, Springer Link, Scopus, Web of Science, and Ovid databases. Randomized controlled trials that investigate the effect of prewarming on body temperature in the prevention of perioperative hypothermia were included. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. Methodological quality was assessed using the Cochrane Collaboration "risk of bias" tool. Meta-analysis was performed with Comprehensive Meta-Analysis, version 2. Moderator analysis and publication bias assessment were performed. Funnel plots were analyzed using Orwin's fail-safe N, Trim, and Fill test method to investigate the source of heterogeneity.

FINDINGS

A total of 907 studies were found. The systematic review included 27 studies. Of these, 23 were included in the intraoperative meta-analysis, and 16 were included in the postoperative meta-analysis. According to the meta-analysis results, the prewarming intervention was effective in maintaining normothermia in the intraoperative (Hedge's g = 0.972, 95% confidence intervaI = 0.674 to 1.270) and postoperative (Hedge's g = 0.818, 95% confidence intervaI = 0.520 to 1.114) periods.

CONCLUSIONS

The findings of this systematic review and meta-analysis showed that preoperative prewarming played a significant role in providing and maintaining perioperative normothermia.

The effectiveness of warming approaches in preventing perioperative hypothermia: Systematic review and meta-analysis

AIM

To assess if experimental warming interventions are superior to routine warming interventions in preventing perioperative hypothermia.

BACKGROUND

Perioperative hypothermia is a critical issue for the complications of surgery. There are various kinds of perioperative warming interventions, including experimental and routine warming interventions.

METHODS

We performed a systematic literature review and meta-analysis for the randomized clinical trials of experimental warming interventions vs. routine warming interventions in the perioperative period.

FINDINGS

A total of 15 studies were included with 983 participants allocated to experimental warming interventions and 939 controls with routine warming interventions, who were receiving a variety of surgeries. The focused outcome was the intraoperative and postoperative body temperature. All included studies were randomized clinical trials. Among the participants receiving operations, the meta-analysis showed that routine warming intervention groups experienced lower intraoperative and postoperative body temperatures compared to the experimental warming groups. The meta-analysis results included positive mean differences, significant tests for overall effect and significant heterogeneity in the random-effects model.

CONCLUSIONS

In spite of significant heterogeneity, experimental warming interventions are likely to demonstrate superior warming effects when compared to routine warming interventions, as shown by the current meta-analysis results of randomized clinical trials.

Redistributional Hypothermia Prevention by Prewarming with Forced-Air: Exploratory, Open, Randomized, Clinical Trial of Efficacy

Avoiding redistributional hypothermia that decreases core temperature by 0.5-1.5°C within the 1st hour of surgery is difficult. The efficacy of prewarming using a forced-air warming (FAW) device with a lower-body blanket on redistribution hypothermia during epidural procedures have not been investigated. After ethics approval, 113 patients undergoing laparoscopic surgery under general anesthesia combined with epidural anesthesia were enrolled. Intervention (prewarming) group patients who were warmed from operating room entry, including during epidural anesthesia, was compared with the control group that was warmed from just before surgery started. In total, 104 patients (52, control; 52, prewarming) were analyzed. In the prewarming group, compared to the control group, the core temperature 20 minutes after anesthesia induction (36.9 ± 0.4 vs. 37.1 ± 0.4°C, p < 0.02) was significantly higher. The core temperature was higher in the prewarming group than in the control group until 3 hours after the surgery. In the prewarming group, compared to the control group, the core temperature-time integral below baseline till 180 minutes after surgery start (65.1 ± 64.0 vs. 8.1 ± 18.6°C/min, p < 0.0001) or 30 minutes after anesthesia induction (5.3 ± 6.2 vs. 2.0 ± 4.7°C/min, p < 0.0001) were significantly smaller. Postoperative shivering was comparable between the groups. Prewarming during epidural catheter insertion with a FAW device could safely prevent a core temperature decrease induced by redistribution or heat loss without additional preparation, effort, space, or time requirements.

The Effect of Active Warming on Postoperative Hypothermia on Body Temperature and Thermal Comfort: A Randomized Controlled Trial

PURPOSE

The purpose of this study was to determine the effect of active warming method in temperature control and thermal comfort in hypothermia after surgery.

DESIGN

A randomized controlled trial.

METHODS

The study sample consisted of 64 male and female postanesthesia care unit and intensive care unit neurosurgery postoperative inpatients. The experimental group was warmed using the active warming method, and the control group's routine care was continued via a cotton blanket. Patients were warmed until their tympanic body temperature reached 37°C.

FINDINGS

The time needed to adequately warm patients was approximately twice as short in those who received active warming as compared with the control group. The perception of thermal comfort was significantly higher in the first hour in patients who received the active warming method (P < .05).

CONCLUSIONS

The active warming method resulted in a shorter time to warming in hypothermia after surgery and an increase in the perception of thermal comfort and body temperature.

Intraoperative surgical site infection control and prevention: a position paper and future addendum to WSES intra-abdominal infections guidelines

BACKGROUND

Surgical site infections (SSI) represent a considerable burden for healthcare systems. They are largely preventable and multiple interventions have been proposed over past years in an attempt to prevent SSI. We aim to provide a position paper on Operative Room (OR) prevention of SSI in patients presenting with intra-abdominal infection to be considered a future addendum to the well-known World Society of Emergency Surgery (WSES) Guidelines on the management of intra-abdominal infections.

METHODS

The literature was searched for focused publications on SSI until March 2019. Critical analysis and grading of the literature has been performed by a working group of experts; the literature review and the statements were evaluated by a Steering Committee of the WSES.

RESULTS

Wound protectors and antibacterial sutures seem to have effective roles to prevent SSI in intra-abdominal infections. The application of negative-pressure wound therapy in preventing SSI can be useful in reducing postoperative wound complications. It is important to pursue normothermia with the available resources in the intraoperative period to decrease SSI rate. The optimal knowledge of the pharmacokinetic/pharmacodynamic characteristics of antibiotics helps to decide when additional intraoperative antibiotic doses should be administered in patients with intra-abdominal infections undergoing emergency surgery to prevent SSI.

CONCLUSIONS

The current position paper offers an extensive overview of the available evidence regarding surgical site infection control and prevention in patients having intra-abdominal infections.

Evaluation of Warming Effectiveness on Physiological Indices of Patients Undergoing Laparoscopic Cholecystectomy Surgery: A Randomized Controlled Clinical Trial

PURPOSE

The present study aimed to evaluate the impact of warming on physiological indices of patients undergoing laparoscopic cholecystectomy.

DESIGN

The study was a three-group randomized controlled clinical trial.

METHODS

In the present study, 96 patients were assigned to three groups: forced-air warming system group; warmed intravenous fluid group; and control group. The intervention was performed immediately after the anesthesia induction. Physiological indices (core body temperature, blood pressure, and heart rate) were evaluated at 15-minute intervals, and postoperative shivering was also recorded.

FINDINGS

The mean systolic blood pressure and the mean heart rate were significantly different in each warming group before, during, and after surgery, but the three groups had no significant differences in terms of physiological indices at any time (P > .05). Postoperative shivering was not seen in any group.

CONCLUSIONS

Both interventions had similar effects on physiological indices. Therefore, the recommendation is to use the warming method according to patient's other conditions.

Effect of "An Innovative Technology" Active Warming and Passive Warming on Unplanned Hypothermia During Perioperative Period: A Clinical Trial

Patients are at risk for unplanned hypothermia during the perioperative period due to many reasons, including anesthesia, low room temperature, cold intravenous fluid, and blood transfusion. This study was conducted to examine the effect of active and passive warming methods applied in patients during the perioperative period on unplanned hypothermia. This study is a case-control type study. The population of this study is composed of the patients hospitalized in surgical clinic and undergone abdominal region-related operations. Ninety patients were accidentally included in the study. The first group of patients were actively warmed during the perioperative period (carbon fiber resistive system - W-500D + 190 × 50 cm), the second group was passively warmed at least for 20 minutes during preoperative period (with blanket, socks etc.), and the third group was followed up as the control group. It was established that body temperature average of the active warming group has significantly increased during perioperative period (p < 0.001), and this temperature was significantly higher than the other groups until the third hour. It was found that the body temperature average of all groups was equal to 36.2 ± 0.26, 35.4 ± 0.49, and 35.2 ± 0.47, respectively, at the end of operation, and the difference among them was statistically significant (p ≤ 0.001). The active warming method applied with carbon fiber resistive system during the perioperative period is an effective method.

Efficacy of forced-air warming for preventing perioperative hypothermia and related complications in patients undergoing laparoscopic surgery: A randomized controlled trial

BACKGROUND

Perioperatively, unexpected hypothermia may cause adverse surgical outcomes. However, few studies have explored the efficacy of forced-air warming in patients undergoing laparoscopic surgery.

AIM/OBJECTIVE

To determine the efficacy of forced-air warming for preventing perioperative hypothermia and complications in patients undergoing laparoscopic surgery.

METHODS

A total of 127 participants undergoing laparoscopic thoracic or abdominal surgery were recruited between January and November 2015. Participants were randomly allocated to intervention (forced-air warming, n = 64) and control groups (passive insulation, n = 63). Oesophageal core temperature was measured during surgery, whilst tympanic core temperature was measured every 30 minutes preoperatively and in the postanaesthesia care unit. Levels of shivering and pain, amount of bleeding, and adverse cardiac events were measured before the transfer from the postanaesthesia care unit. The generalized estimating equation was used for data analysis.

RESULTS

The intervention group had better warming efficacy than the control group between 90 and 330 minutes during surgery. The intervention group had fewer complications than the control group in terms of intraoperative bleeding, time to rewarm to 36°C, pain levels, and shivering levels in the postanaesthesia care unit.

CONCLUSION

Forced-air warming can increase warming efficacy and reduce complications of perioperative hypothermia in patients undergoing laparoscopic surgery.

A novel thermal compression device for perioperative warming: a randomized trial for feasibility and efficacy

Background

Inadvertent perioperative hypothermia (IPH) leads to surgical complications and increases length of stay. IPH rates are high with the current standard of care, forced air warming (FAW). Our hypothesis is that a prototype thermal compression device that heats the popliteal fossa and soles of the feet, with lower leg compression, increases perioperative temperatures and reduces IPH compared to the current standard of care.

Methods

Thirty six female breast surgery patients, at a tertiary academic hospital, were randomized to the device or intraoperative FAW (stage I) with a further 18 patients randomized to the device with a single heating area only (stage II, popliteal fossa or sole of the feet). Stage I: 37 patients recruited (final 36). Stage II: 18 patients recruited (final 18). Inclusion criteria: general anesthesia with esophageal monitoring for over 30 min, legs available and able to fit the device and no contraindications to leg heating or compression. The intervention was: Stage I: Investigational prototype thermal compression device (full device group) or intraoperative FAW. Stage II: Device with only a single heating location. Primary outcomes were perioperative temperatures and incidence of IPH. Secondary outcomes were local skin temperature, general and thermal comfort scores and presence of perioperative complications, including blood loss.

Results

Mean temperatures in the full device group were significantly higher than the FAW group in the pre-operative (36.7 vs 36.4 °C, p < 0.001), early intraoperative (36.3 vs 35.9 °C, p < 0.001), intraoperative (36.6 vs 36.2 °C, p < 0.001) and postoperative periods (36.8 vs 36.5 °C, p < 0.001). The incidence of IPH in the device group was also significantly lower (16.7% vs 72.0%, p = 0.001). Thermal comfort scores were significantly higher in the full device group and hypothermia associated wound complications were higher in the FAW group.

Conclusions

The thermal compression device is feasible and has efficacy over the FAW. Further studies are recommended to investigate clinically significant outcomes.

Trial registration

clinicaltrials.gov (NCT02155400)

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-017-0395-2) contains supplementary material, which is available to authorized users.

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.

Intraoperative body temperature control: esophageal thermometer versus infrared tympanic thermometer

Abstract OBJECTIVE To verify the correlation between temperature measurements performed using an infrared tympanic thermometer and an esophageal thermometer during the intraoperative period. METHOD A longitudinal study of repeated measures was performed including subjects aged 18 years or older undergoing elective oncologic surgery of the digestive system, with anesthesia duration of at least 1 hour. Temperature measurements were performed simultaneously by a calibrated esophageal thermometer and by a calibrated infrared tympanic thermometer, with laboratory reading precision of ±0.2ºC. The operating room temperature remained between 19 and 21ºC. RESULTS The study included 51 patients, mostly men (51%), white (80.4%). All patients were kept warm by a forced-air heating system, for an average of 264.14 minutes (SD = 87.7). The two temperature measurements showed no different behavior over time (p = 0.2205), however, tympanic measurements were consistently 1.24°C lower (p<0.0001). CONCLUSION The tympanic thermometer presented reliable results but reflected lower temperatures than the esophageal thermometer.

The Optimal Time and Method for Surgical Prewarming: A Comprehensive Review of the Literature

PURPOSE

Inadvertent hypothermia is a common problem in the operating room. This can contribute to many unfavorable outcomes --rising costs, increased complications, and higher morbidity rates.

DESIGN

This review determined the optimal method and time to prewarm a surgical patient to prevent perioperative hypothermia.

METHODS

CINAHL and PubMed were searched. Fourteen articles were ultimately included in this review.

FINDINGS

Based on the literature reviewed, it was suggested that forced-air warming was most effective in preventing perioperative hypothermia. Eighty-one percent of the experimental studies reviewed found that there was a significantly higher temperature throughout surgery and in the postanesthesia care unit for patients who received forced-air prewarming.

CONCLUSIONS

Thirty minutes was found to be the average suggested amount of time for prewarming among the literature; however, a minimum of 10 minutes of prewarming was suggested to significantly reduce rates of hypothermia in perioperative patients and decrease the adverse effects of hypothermia.

Meta-analysis: effectiveness of forced-air warming for prevention of perioperative hypothermia in surgical patients

AIM

The aim of this study was to evaluate the effectiveness of forced-air warming for preventing perioperative hypothermia.

BACKGROUND

Perioperative hypothermia commonly occurs in patients receiving anaesthesia during surgeries. However, the effectiveness of warming systems requires verification.

DESIGN

Systematic review incorporating meta-analysis.

DATA SOURCES

We searched OVID, PubMed, Cochrane Library, Medline, CINAHL, CETD and CEPS databases (2001-2015) for randomized controlled trials published in English and Chinese. Outcome measures of interests were body temperature and thermal comfort.

REVIEW METHODS

Cochrane methods, Quality of evidence (GRADE) assessments and Jadad Quality Score were used.

RESULTS

Twenty-nine trials (1875 patients) met inclusion criteria, including seven trials (502 patients) related to thermal comfort. Results showed that: (1) forced-air warming was more effective than passive insulation and circulating-water mattresses; (2) there was no statistically significant difference among forced-air warming, resistive heating blankets, radiant warming systems and circulating-water garments; and (3) that thermal comfort provided by forced-air warming was superior to that of passive insulation, resistive heating blankets and radiant warming systems, but inferior to that of circulating-water mattresses.

CONCLUSIONS

Forced-air warming prevents perioperative hypothermia more effectively than passive insulation and circulating-water mattresses, whereas there is no statistically significant difference in its effectiveness compared with circulating-water garments, resistive heating blankets and radiant warming systems.

Peri-operative warming devices: performance and clinical application

Since the adverse consequences of accidental peri-operative hypothermia have been recognised, there has been a rapid expansion in the development of new warming equipment designed to prevent it. This is a review of peri-operative warming devices and a critique of the evidence assessing their performance. Forced-air warming is a common and extensively tested warming modality that outperforms passive insulation and water mattresses, and is at least as effective as resistive heating. More recently developed devices include circulating water garments, which have shown promising results due to their ability to cover large surface areas, and negative pressure devices aimed at improving subcutaneous perfusion for warming. We also discuss the challenge of fluid warming, looking particularly at how devices' performance varies according to flow rate. Our ultimate aim is to provide a guide through the bewildering array of devices on the market so that clinicians can make informed and accurate choices for their particular hospital environment.