Clinical practice guideline. Unintentional perioperative hypothermia

Intraoperative hypothermia in patients with laparoscopic surgery: Influencing factors and prevention strategies

Background

Effective body temperature management is crucial for the favorable prognosis of patients undergoing surgery. The purpose of this study is to explore the risk factors of intraoperative hypothermia and to develop a risk prediction model to provide basis for clinical treatment.

Methods

Patients who underwent laparoscopic surgery in a tertiary hospital in China from February 1, 2023 to January 31, 2024 were included. The body temperature characteristics of patients in hypothermia group and non-hypothermia group were collected and evaluated. Univariate and Logistic regression analysis were used to evaluate the influencing factors. Based on the regression coefficients of risk factors, a risk prediction model of hypothermia was established. The model was assessed by Hosmer's Lemeshow (H- L) test and receiver working characteristic (ROC) curve.

Results

In 216 patients undergoing laparoscopic surgery, the incidence of hypothermia was 52.78 %. BMI≤23 kg/m2(OR = 2.061, 95%CI: 1.413-3.263), basal body temperature≤36.1 °C (OR = 3.715, 95%CI: 3.011-4.335), operating room temperature≤22 °C (OR = 2.481, 95%CI: 1.906-3.014), length of surgery≥120 min (OR = 2.228, 95%CI: 1.925-2.981) were the risk factors of hypothermia in patients undergoing laparoscopic surgery (all P < 0.05). The P value of H-L test was 0.098, the area under ROC curve and 95%CI were 0.806 (0.746-0.869). The sensitivity and specificity of the model in this study were good.

Conclusions

Patients undergoing laparoscopic surgery are at a high risk of developing hypothermia, a condition influenced by a multitude of factors. This model is designed to be integrated into clinical practice, enabling healthcare providers to identify patients with a higher risk and to implement targeted preventive measures.

Perioperative hypothermia prevention: development of simple principles and practice recommendations using a multidisciplinary consensus-based approach

OBJECTIVES

To develop a consensus on evidence-based principles and recommendations for perioperative hypothermia prevention in the Australian context.

DESIGN

This study was informed by CAN-IMPLEMENT using the ADAPTE process: (1) formation of a multidisciplinary development team; (2) systematic search process identifying existing guidance for perioperative hypothermia prevention; (3) appraisal using the AGREE II Rigor of Development domain; (4) extraction of recommendations from guidelines meeting a quality threshold using the AGREE-REX tool; (5) review of draft principles and recommendations by multidisciplinary clinicians nationally and (6) subsequent round of discussion, drafting, reflection and revision by the original panel member team.

SETTING

Australian perioperative departments.

PARTICIPANTS

Registered nurses, anaesthetists, surgeons and anaesthetic allied health practitioners.

RESULTS

A total of 23 papers (12 guidelines, 6 evidence summaries, 3 standards, 1 best practice sheet and 1 evidence-based bundle) formed the evidence base. After evidence synthesis and development of draft recommendations, 219 perioperative clinicians provided feedback. Following refinement, three simple principles for perioperative hypothermia prevention were developed with supporting practice recommendations: (1) actively monitor core temperature for all patients at all times; (2) warm actively to keep body temperature above 36°C and patients comfortable and (3) minimise exposure to cold at all stages of perioperative care.

CONCLUSION

This consensus process has generated principles and practice recommendations for hypothermia prevention that are ready for implementation with local adaptation. Further evaluation will be undertaken in a large-scale implementation trial across Australian hospitals.

Relationship between perfusion index and central temperature before and after induction of anesthesia in laparoscopic gastrointestinal surgery: A prospective cohort study

The perfusion index (PI) cutoff value before anesthesia induction and the ratio of PI variation after anesthesia induction remain unclear. This study aimed to clarify the relationship between PI and central temperature during anesthesia induction, and the potential of PI in individualized and effective control of redistribution hypothermia. This prospective observational single center study analyzed 100 gastrointestinal surgeries performed under general anesthesia from August 2021 to February 2022. The PI was measured as peripheral perfusion, and the relationship between central and peripheral temperature values was investigated. Receiver operating characteristic curve analysis was performed to identify baseline PI before anesthesia, which predicts a decrease in central temperature 30 minutes after anesthesia induction, and the rate of change in PI that predicts the decrease in central temperature 60 minutes after anesthesia induction. In cases with a central temperature decrease of ≥ 0.6°C after 30 minutes, the area under the curve was 0.744, Youden index was 0.456, and the cutoff value of baseline PI was 2.30. In cases with a central temperature decrease of ≥ 0.6°C after 60 minutes, the area under curve was 0.857, Youden index was 0.693, and the cutoff value of the PI ratio of variation after 30 minutes of anesthesia induction was 1.58. If the baseline PI is ≤ 2.30 and the PI 30 minutes after anesthesia induction is at least 1.58-fold the PI ratio of variation, there is a high probability of a central temperature decrease of at least 0.6°C within 30 minutes after 2 time points.

Clinical Survey of Current Perioperative Body Temperature Management: What Major Factors Influence Effective Hypothermia Prevention Practice?

Purpose

Inadvertent intraoperative hypothermia (IIH) is generally associated with several postoperative complications. Inspite of the existing guidelines, the global incidence of IIH remains unacceptably high. Understanding the conditions that influence temperature management is critical for developing future interventions to improve the postoperative patient outcomes. This study aimed to identify the major factors that hinder the implementation of IIH prevention practices.

Methods

Through a literature research, pilot small-sample investigation, and expert suggestions, 11 factors that may hinder the implementation of IIH prevention practices were identified. A questionnaire was developed, and each question was used to assess each factor. After approval by the Research Ethics Board, the questionnaires were sent to the staff anaesthesiologists at two academic hospitals via WeChat. Each answer was coded according to the degree to which the factor was affected, as anticipated. Finally, the answers were analysed based on the 80/20 rule to identify the major barriers to effective temperature management.

Results

We included 195 participants. Knowledge, memory, attention and decision processes, beliefs about consequences, and environmental context and resources were the major factors, with cumulative composition ratios of 24%, 43.4%, 57.7%, and 70.7%, respectively. Meanwhile, behavioural regulation and social influence were the secondary factors, with cumulative composition ratios of 80.4% and 87.5%, respectively. Reinforcement, confidence in capacity, duty realisation, skills, and intention were the general factors with cumulative composition ratios of 94.3%, 99.8%, 100%, 100%, and 100%, respectively.

Conclusion

Four factors-knowledge, memory, attention and decision process, beliefs about consequences, and environmental context and resources-were the major factors that influence the effective hypothermia prevention practice.

Relevance to Clinical Practice

These major factors will be used in further studies as a basis to develop the corresponding solutions and improve the patient outcomes in clinical practice.

Evidence-based clinical practice guidelines for the management of perioperative hypothermia: Systematic review, critical appraisal, and quality assessment with the AGREE II instrument

Inadvertent perioperative hypothermia is considered an emergency life-threatening situation. Clinical practice guidelines (CPGs) on how to manage hypothermia, based on evidence and expert opinions, could save lives. This systematic review assessed and compared the most recently approved international CPGs with the AGREE II instrument. We searched international bibliographic databases to identify relevant guidelines for managing perioperative hypothermia. Four independent reviewers (consultant anesthesiologists) critically appraised the selected guidelines with the AGREE II instrument. We analyzed inter-rater agreement and calculated an intra-class correlation coefficient (Kappa). We identified five CPGs for perioperative hypothermia that were eligible for critical appraisal. These CPGs were issued by the National Institute for Health and Care Excellence (NICE-2016); the American Society of Peri-Anesthesia Nurses/Agency for Health Care Research and Quality (ASPAN/AHRQ-2006); the University of Southern Mississippi (USM/CPG-2017); The University Assistance Complex of Salamanca (UACS/CPG-2018); and the Justus-Liebig University of Giessen (UKGM/CPG-2015). The overall assessments of NICE-2016 and ASPAN/AHRQ-2006 scored >80%. These results were consistent with high scores achieved in the six domains of AGREE II: (1) scope and purpose, (2) stakeholder involvement, (3) rigor of development, (4) clarity of presentation, (5) applicability, and (6) editorial independence domains. The NICE-2016, ASPAN/AHRQ-2006, and USM/CPG-2017) scored, respectively, 94%, 81%, and 70% for domain 3, 91%, 87%, and 66% for domain 5, and 90%, 82%, and 77% for domain 6. Generally, the NICE CPGs received significantly better clinical recommendations. However, all five evidence-based CPGs were of high methodological quality and were recommended for use in practice. Saudi Arabia should formulate its own national CPGs for diagnosis and management of perioperative hypothermia and to be published on NICE.

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Guidance for adapting CPGs to a given clinical practice is a realistic, practical alternative to de novo CPG development, which is a time-consuming and resource-intensive approach.

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Some nations, particularly those with low- and middle-income economies, have chosen to employ CPG adaptation, rather than developing new evidence-based practice programs.

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Several formal adaptation approaches are currently available, and they may be tailored further to suit particular circumstances. Evaluations like the one described in the present study should provide guidance for appropriate CPG adaptation or development efforts, particularly for organizations with little expertise with the AGREE II instrument.

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The current critical appraisal emphasized the importance of clinicians performing quality assessments of CPGs to ensure transparency and strength in the CPG development process, in accordance with international CPG standards. Moreover, our findings will support the provision of best practices for POH. Based on our findings, we propose that anesthesiologists should include an AGREE II review of CPGs in their capacity development strategies.

Development and Validation of a Questionnaire of the Perioperative Nursing Competencies in Patient Safety

(1) Background: This research presents the CUCEQS© (Spanish acronym for Questionnaire of Perioperative Nursing Safety Competencies), which evaluates the perception of perioperative nurses about their competencies related to surgical patient safety. The aim of the present study was to design, validate, and analyze the psychometric properties of the CUCEQS©. (2) Methods: We devised an instrumental, quantitative, and descriptive study divided into two phases: in the first, the questionnaire was designed through a Delphi method developed by perioperative nurses and experts in patient safety. In the second, the reliability, validity, and internal structure of the tool were evaluated. (3) Results: In the first phase, the items kept were those that obtained a mean equal to or higher than four out of five in the expert consensus, and a Content Validity Index higher than 0.78. In the second phase, at the global level, a Stratified Cronbach's Alpha of 0.992 was obtained, and for each competency, Cronbach's Alpha values between 0.81 and 0.97 were found. A first-order confirmatory factor analysis of the 17 subscales (RMSEA 0.028, (IC 90% = 0.026-0.029) and its observed measures was performed for the 164 items, as well as a second-order analysis of the four competencies (RMSEA = 0.034, (IC90% = 0.033-0.035). (4) Conclusions: The questionnaire is a valid tool for measuring the perceived level of competency by the perioperative nurses in surgical patient safety. This is the first questionnaire developed for this purpose, and the results obtained will facilitate the identification of areas to be improved by health professionals in patient safety.

Effect of prewarming on body temperature in short-term bladder or prostatic transurethral resection under general anesthesia: A randomized, double-blind, controlled trial

Perioperative hypothermia causes postoperative complications. Prewarming reduces body temperature decrease in long-term surgeries. We aimed to assess the effect of different time-periods of prewarming on perioperative temperature in short-term transurethral resection under general anesthesia. Randomized, double-blind, controlled trial in patients scheduled for bladder or prostatic transurethral resection under general anesthesia. Eligible patients were randomly assigned to receive no-prewarming or prewarming during 15, 30, or 45 min using a forced-air blanket in the pre-anesthesia period. Tympanic temperature was used prior to induction of anesthesia and esophageal temperature intraoperatively. Primary outcome was the difference in core temperature among groups from the induction of general anesthesia until the end of surgery. Repeated measures multivariate analysis of covariance modeled the temperature response at each observation time according to prewarming. We examined modeled contrasts between temperature variables in subjects according to prophylaxis. We enrolled 297 patients and randomly assigned 76 patients to control group, 74 patients to 15-min group, 73 patients to 30-min group, and 74 patients to the 45-min group. Temperature in the control group before induction was 36.5 ± 0.5 °C. After prewarming, core temperature was significantly higher in 15- and 30-min groups (36.8 ± 0.5 °C, p = 0.004; 36.7 ± 0.5 °C, p = 0.041, respectively). Body temperature at the end of surgery was significantly lower in the control group (35.8 ± 0.6 °C) than in the three prewarmed groups (36.3 ± 0.6 °C in 15-min, 36.3 ± 0.5 °C in 30-min, and 36.3 ± 0.6 °C in 45-min group) (p < 0.001). Prewarming prior to short-term transurethral resection under general anesthesia reduced the body temperature drop during the perioperative period. These time-periods of prewarming also reduced the rate of postoperative complications.Study Registration Registered at ClinicalTrials.gov (Identifier: NCT03630887).

Incidence of Severe Hypothermia and Its Impact on Postoperative Surgical Complications and Time Delay to Adjunct Treatments in Breast Surgery Cancer Patients: A Case-Controlled Study

Introduction: Unintended postoperative hypothermia frequently occurs upon arrival in the post anesthesia care unit (PACU). As part of our quality assurance program in anesthesia, we regularly monitor the incidence of this complication through our anesthesia information management system (AIMS). In this case-controlled retrospective study, our goal was to detect the incidence of unintended severe hypothermia in our breast surgery cancer patients, and subsequently to analyze the consequence of this complication in terms postoperative cutaneous infection, as well as its impact on further complementary treatment, such as radiotherapy and chemotherapy. Methods: This study was a retrospective analysis conducted through our AIMS system from 2015 through 2019, with extraction criteria based on year, type of surgery (breast), and temperature upon arrival in PACU. A tympanic temperature of less than 36 °C was considered to indicate hypothermia. Severe hypothermia was considered for patients having a temperature lower than 35.2 °C (hypothermic) (n = 80), who were paired using a propensity score analysis with a control group (normothermic) (n = 80) of other breast cancer surgery patients. Extracted data included time of surgery, sex, age, ASA status, and type and duration of the intervention. Results: The mean incidence of hypothermia was 21% from 2015 through 2019. The body mass index (BMI) was significantly lower in the hypothermia group before matching, 23.5 ± 4.1 vs. 26.4 ± 6.1 kg/m² in normothermic patients (p < 0.05). The hypothermia group also had significantly fewer monitoring and active warming devices. No difference was noted for wound complications. Time to complementary chemotherapy and or radiotherapy did not differ between groups (52 ± 21 days in group hypothermia vs 49 ± 22 days in the control group). Conclusion: Severe intraoperative hypothermia remains an important quality assurance issue in our breast surgery cancer patients, but we could not detect any long-term effect of hypothermia.

Short-Periods of Pre-Warming in Laparoscopic Surgery. A Non-Randomized Clinical Trial Evaluating Current Clinical Practice

Background: Pre-warming prevents perioperative hypothermia. We evaluated the current clinical practice of pre-warming and its effects on temperature drop and postoperative complications; Methods: This prospective, observational pilot study examines clinical practice in a tertiary hospital on 99 patients undergoing laparoscopic urological surgery. Pre-warming was performed in the pre-anesthesia room. Patients were classified into three groups: P 0 (non-prewarmed), P 5–15 (pre-warming 5–15 min) and P > 15 (pre-warming 15–30 min). Tympanic temperature was recorded in the pre-anesthesia room, prior to anesthesia induction, and in the PACU. Esophageal temperature was recorded intraoperatively. The occurrence of shivering, pain intensity, length of stay in PACU, and postoperative complications during hospital stay were also recorded; Results: After pre-warming, between-group difference in body temperature was higher in P > 15 than in P 0 (0.4 °C, 95% CI 0.14–0.69, p = 0.004). Between P 5–15 and P 0 difference was 0.2 °C (95% CI 0.04–0.55, p = 0.093). Temperature at the end of surgery was higher in pre-warmed groups [mean between-group difference 0.5 °C (95% CI 0.13–0.81, p = 0.007) for P 5–15; 0.9 °C (95% CI 0.55–1.19, p < 0.001) for P > 15]. Pain and shivering was less common in pre-warmed groups. Postoperative transfusions and surgical site infections were lower in P > 15; Conclusion: Short-term pre-warming prior to laparoscopic urological surgery decreased temperature perioperative drop and postoperative complications.

Prospective observational study of the effectiveness of prewarming on perioperative hypothermia in surgical patients submitted to spinal anesthesia

Prewarming has been shown to prevent intraoperative inadvertent hypothermia. Nevertheless, data about optimal prewarming-time from published clinical trials report contradictory results. We conducted this pilot study to evaluate routine clinical practice regarding prewarming and its effect on the prevalence of perioperative hypothermia in patients undergoing transurethral resection (TUR) under spinal anesthesia. This was a prospective, observational, pilot study to examine clinical practice in a tertiary hospital regarding prewarming in 140 consecutive patients. When prewarming (pw) was performed, forced-air warming was provided in the pre-anesthesia room for 15 (pw15), 30 (pw30), or 45 (pw45) min. Tympanic temperature was recorded upon entering the pre-anesthesia room, at the time of initiating surgery, and every 15 min intra-operatively. We also recorded duration of the surgical procedure and length of stay in the Post-Anesthesia Care Unit (PACU). Pw15 was performed in 34 patients, pw30 in 29 patients, and pw45 in 21 patients. Fifty-six patients did not receive pw and 96% of them developed hypothermia at the end of the surgical procedure, compared to 73% of patients in pw15 (p = 0.002), 75% in pw30 (p = 0.006) and 90% in pw45 (p = 0.3). Length of stay in the PACU was markedly shorter in pw15 (131 ± 69 min) and pw30 (123 ± 60 min) than in the non-pw group (197 ± 105 min) (p = 0.015 and p = 0.011, respectively). This difference was not significant in pw45 (129 ± 56 min) compared to non-pw patients. In conclusion, prewarming for 15 or 30 min before TUR under spinal anesthesia prevents development of hypothermia at the end of the surgical procedure.