Effect of active forced air warming during the first hour after anesthesia induction and intraoperation avoids hypothermia in elderly patients

Advances in the multimodal management of perioperative hypothermia: approaches from traditional Chinese and Western medicine

PURPOSE

Maintaining normothermia during the perioperative period is crucial for preventing complications, such as surgical site infections, prolonged hospital stays, and adverse cardiovascular events. This study aimed to elucidate methods of perioperative temperature management by integrating Western and traditional Chinese medicine (TCM) approaches. By combining advanced techniques of Western medicine with holistic and preventative practices of TCM, we aimed to provide a comprehensive strategy for effective perioperative thermal regulation.

METHODS

And a comprehensive literature review was conducted to analyze the causes of perioperative hypothermia and methods of perioperative temperature management from both Western and traditional Chinese medicine (TCM) perspectives. Special emphasis was placed on evaluating the underlying factors contributing to perioperative hypothermia, as well as the effectiveness, selection criteria, indications, contraindications, adverse reactions, and potential complications associated with various temperature management techniques.

RESULTS

Effective prevention and management strategies include preoperative risk assessment, physical warming measures, environmental temperature control, pharmacological interventions, perioperative temperature monitoring, comprehensive warming protocols, and postoperative warming and monitoring. Integrating traditional Chinese medicine provides additional methods to enhance overall effectiveness and patient outcomes. By combining these approaches, healthcare providers can significantly reduce the incidence of inadvertent perioperative hypothermia (IPH) and its associated complications, improving patient safety and recovery.

CONCLUSION

For IPH, a complex and challenging medical condition, both traditional Chinese medicine and Western medicine have established their own theoretical bases and developed corresponding prevention and treatment methods. However, it is important to note that although each of these methods has unique value and potential, they also have specific indications and unavoidable limitations. Therefore, by integrating and combining the complementary strengths and resources of traditional Chinese medicine and Western medicine, we can achieve a more comprehensive and effective prevention of IPH, ultimately improving the health and well-being of those affected.

Effects of different forced-air warming systems on the core temperature of patients: a manikin and multi-center clinical study

BACKGROUND

The use of forced-air warming (FAW) blankets is widely recognized for preventing shivering and hypothermia in patients under general anesthesia. Various types of products are currently available for hospitals, and we have conducted a preliminary evaluation of insulation equipment based on expert opinions and initial parameters. However, we lack real-world experiments and accurate clinical data to validate these parameters and the accuracy of our decision-making results. This study aims to confirm the effectiveness of different FAW systems by assessing the thermal protection and operational characteristics of the equipment in both experimental and clinical settings, thereby enhancing our evaluation database.

METHODS

In the manikin test, we conducted six tests including heat distribution and heating rate, heater outlet temperature stability, etc. In the clinical study, patients were randomly assigned to four groups [Group A (Bair Hugger Therapy, 3 M, St. Paul, MN, USA; 63500); Group B (EQUATOR® level I, Smith Medical ASD, MN, USA; Snuggle Warm, SW-2013); Group C (Jiang Men Da Cheng Medical Devices Co., Ltd, China; IOB-006); and Group D (Shang Hai Nest Tech Medical Materials Co., Ltd, China; BH-017)], with each group comprising 30 individuals. At the start of anesthesia induction, the FAW blanket was activated and set to 43 °C until the completion of surgery. The primary endpoint was the average core body temperature during surgery. Secondary endpoints included hemodynamic and surgical variables, adverse events, and recovery metrics.

RESULTS

In the manikin test, the observed results of the experimental parameters (heat distribution, air pressure difference, and hole observation test) for Group A are superior to those of the other groups. In the clinical study, although the mean perioperative core body temperature remained above 36 °C across all groups [Group A: 36.31 ± 0.04; Group B: 36.26 ± 0.06; Group C: 36.17 ± 0.03; Group D: 36.25 ± 0.05], patients in Group A maintained higher temperatures compared to the other groups (p < 0.001).

CONCLUSIONS

Among patients undergoing laparoscopic radical resection of colorectal cancer with general anesthesia, all four FAW systems effectively prevented perioperative hypothermia. However, the system in Group A minimized heat loss more effectively than the others, providing superior thermal protection.

TRIAL REGISTRATION

ChiCTR2200065394, 03/11/2022.

The Effect of Temperature Chain Management Scheme During Robot-Assisted Radical Prostatectomy

The study aimed to explore the effect of the temperature chain management scheme on preventing hypothermia in patients undergoing robot-assisted radical prostatectomy (RARP). The patients were randomized to receive either intraoperative warming only (control group, Group C) or the temperature chain management (experimental group, Group T). We compared the core temperature, inadvertent perioperative hypothermia (IPH) rates, the incidence of shivering, and thermal comfort between the two groups. The perioperative core temperature of the Group T was higher than that of the Group C, and the incidence of IPH, the incidence of shivering in the postanesthesia care unit (PACU), and the length of stay in PACU were lower than those of the control group. The thermal comfort of Group T scored higher than that of Group C when leaving the PACU, all above have a statistically significant difference (p < 0.05). The temperature chain management scheme could decrease the IPH rates and reduce postoperative complications in RARP patients. The Clinical Trials Registration number is 2023IIT034.

Development and validation of an intraoperative hypothermia nomograph model for patients undergoing video-assisted thoracoscopic lobectomy: a retrospective study

This study aimed to develop and internally validate a nomogram model for assessing the risk of intraoperative hypothermia in patients undergoing video-assisted thoracoscopic (VATS) lobectomy. This study is a retrospective study. A total of 530 patients who undergoing VATS lobectomy from January 2022 to December 2023 in a tertiary hospital in Wuhan were selected. Patients were divided into hypothermia group (n = 346) and non-hypothermia group (n = 184) according to whether hypothermia occurred during the operation. Lasso regression was used to screen the independent variables. Logistic regression was used to analyze the risk factors of hypothermia during operation, and a nomogram model was established. Bootstrap method was used to internally verify the nomogram model. Receiver operating characteristic (ROC) curve was used to evaluate the discrimination of the model. Calibration curve and Hosmer Lemeshow test were used to evaluate the accuracy of the model. Decision curve analysis (DCA) was used to evaluate the clinical utility of the model. Intraoperative hypothermia occurred in 346 of 530 patients undergoing VATS lobectomy (65.28%). Logistic regression analysis showed that age, serum total bilirubin, inhaled desflurane, anesthesia duration, intraoperative infusion volume, intraoperative blood loss and body mass index were risk factors for intraoperative hypothermia in patients undergoing VATS lobectomy (P < 0.05). The area under ROC curve was 0.757, 95% CI (0.714-0.799). The optimal cutoff value was 0.635, the sensitivity was 0.717, and the specificity was 0.658. These results suggested that the model was well discriminated. Calibration curve has shown that the actual values are generally in agreement with the predicted values. Hosmer-Lemeshow test showed that χ2 = 5.588, P = 0.693, indicating that the model has a good accuracy. The DCA results confirmed that the model had high clinical utility. The nomogram model constructed in this study showed good discrimination, accuracy and clinical utility in predicting patients with intraoperative hypothermia, which can provide reference for medical staff to screen high-risk of intraoperative hypothermia in patients undergoing VATS lobectomy.

Effect of Aggressive Warming versus Routine Thermal Management on the Incidence of Perioperative Hypothermia in Patients Undergoing Thyroid Surgery: A Prospective, Randomized, Double-Blind Controlled Trial

Purpose

Despite the implementation of various insulation measures, the incidence of hypothermia during thyroid surgery remains high. This randomized controlled study aimed to evaluate the effects of aggressive thermal management combined with resistive heating mattresses to prevent perioperative hypothermia in patients undergoing thyroid surgery.

Patients and Methods

142 consecutive patients scheduled for elective thyroid surgery were enrolled in the study. They were randomly and equally allocated to the aggressive warming or routine care groups (n = 71). The patients' body temperature was monitored before the induction of anesthesia until they returned to the ward. The primary outcome was the incidence of perioperative hypothermia. Secondary outcomes included postoperative complications, such as mortality, cardiovascular complications, wound infection, shivering, postoperative nausea and vomiting (PONV), visual analog scale (VAS) pain scores, fever, headache and hospital length of stay (LOS).

Results

In our study, the results showed that a significantly higher rate of hypothermia was observed in the routine care group compared with the aggressive warming group. The incidence of perioperative hypothermia was 19.72% (14/71) in the aggressive warming group and 35.21% (25/71) in the routine care group (P < 0.05). The incidence of shivering in the aggressive warming group (1.41%) was significantly lower than that in the routine care group (11.27%) (P < 0.05), and a one-day reduction in hospital length of stay was observed in the aggressive warming group (P < 0.05). There was no significant difference in mortality or other postoperative complications, such as cardiovascular complications, wound infection, PONV, pain, fever or headache, between the two groups (P > 0.05).

Conclusion

Our results suggest that aggressive thermal management combined with resistive heating mattresses provided improved perioperative body temperature and reduced the incidence of perioperative hypothermia and shivering compared to routine thermal management.

Effects of a forced-air warming system and warmed intravenous fluids on hemodynamic parameters, shivering, and time to awakening in elderly patients undergoing open cardiac surgery

Background

As one of the most common postoperative complications, hypothermia is the main cause of numerous problems during treatment, especially in elderly patients with decreased cardiac reserves.

Objectives

The aim of the present study was to compare the effects of forced-air warming system (FAWS), warmed intravenous fluids (WIVFs) and routine method on hemodynamic parameters, arterial blood gases (ABGs), shivering, and time to awakening in elderly patients undergoing open cardiac surgery (OCS).

Methods

This clinical randomized controlled trial was conducted on 94 elderly patients who underwent OCS at Ayatollah Rouhani Hospital, Babol, Iran. They were divided into three groups, namely FAWS (n=31), WIVFs (n=31) and routine rewarming method (RRWM, with a blanket) (n=32). The data were then recorded in a checklist. Descriptive and inferential statistics were performed using SPSS 26 at a significance level of less than 0.05.

Results

The findings demonstrated that the degree of hypothermia had a significant decreasing trend in the groups receiving FAWS and WIVFs (P=0.002). Additionally, increased respiratory rate (P=0.013), higher bicarbonate (HCO3-) levels on arrival up to 4 hours after surgery (P=0.045), reduced lactate level (P=0.005), normal base excess (BE) and accelerated time to awakening (P=0.004) were observed in patients receiving FAWS. There was no significant difference in the study groups regarding shivering.

Conclusion

The results revealed that FAWS could mitigate the degree of hypothermia, increase body temperature and decrease the postoperative serum lactate levels. Moreover, BE as one of the most important parameters for ABGs, could remain at a normal level. Besides, the use of FAWS could lead to early awakening, and thus facilitate weaning and extubation of these patients.

Incidence of postoperative hypothermia and shivering and risk factors in patients undergoing malignant tumor surgery: a retrospective study

BACKGROUND

Perioperative hypothermia and shivering are common and can cause adverse outcomes. The aim of this study was to investigate the incidence of postoperative hypothermia and shivering and their risk factors in patients undergoing malignant tumor surgery.

METHODS

This retrospective study collected data from patients with American Society of Anesthesiologists physical status (ASA) I or II who underwent scheduled surgery from November 2020 to March 2021 at Fudan University Shanghai Cancer Center. Each patient's core body temperature was measured at three time points: time point 1 (arrival at the postanesthesia care unit (PACU)), time point 2 (after 30-min care in the PACU), and time point 3 (at discharge from the PACU). At time point 1, if the patient's body temperature was below 36 ℃, we provided an active forced-air warmer. At time point 2, if it was still below 36 ℃, the forced-air warmer was still applied until the patient was discharged from the PACU. If it reached 36 ℃, the forced-air warmer would be switched off. Univariate and multivariate logistic regression combined with stepwise methods and linear regression were used to explore risk factors for postoperative hypothermia and shivering.

RESULTS

The numbers (percentage) of 202 patients who developed postoperative hypothermia at the different time points were 52 (25.7%), 37 (18.3%) and 28 (13.9%). Eight patients (4.0%) experienced shivering. Multivariate logistic regression showed that high weight (OR = 0.923, 95% CI: 0.884 to 0.964, P = 0.0003) and low estimated blood loss (OR = 0.252, 95% CI: 0.115 to 0.550, P = 0.0005) were protective factors against hypothermia, while long surgical duration (OR = 3.339, 95% CI: 1.675 to 6.655, P = 0.0006) was an independent risk factor for hypothermia at time point 1. There was no risk factor associated with the occurrence of shivering (P > 0.05). There was a significant difference between the hypothermia and normothermia groups in the median length of stay in the PACU (59.0 vs. 49.0 min, P = 0.0123).

CONCLUSIONS

Postoperative hypothermia occurred frequently. Weight, estimated blood loss and surgical duration were significantly associated with hypothermia on arrival at the PACU.

Early and Prolonged Mild Hypothermia in Patients with Poor-Grade Subarachnoid Hemorrhage: A Pilot Study

We assessed the feasibility of therapeutic early and prolonged mild hypothermia (MH) in patients with poor-grade subarachnoid hemorrhage (SAH). A retrospective pilot study was conducted for poor-grade SAH patients at two university hospitals from March 2015 to December 2018 who had received MH immediately after coil embolization and maintained a target temperature of 34-35°C for 5 days. A matched controlled design at a 1:2 ratio was used to compare MH therapy outcomes. The primary goal was to assess the two groups' severe functional outcomes at discharge defined as a modified Rankin Scale score of 4-6. The secondary aim was to assess mortality and severe vasospasm depending upon MH. A binary logistic regression analysis was performed to identify relevant risk factors for the outcomes. A total of 54 patients (18 with MH treatment and 36 without MH treatment) were included. Severe functional outcome was significantly decreased in poor-grade SAH patients with MH (n = 7, 38.9%) than those without MH (n = 25, 69.4%; p = 0.031). In patients treated with MH, mortality and severe vasospasm tended to be less common, although the difference was not statistically significant. A binary logistic regression analysis revealed that early and prolonged MH (odds ratio [OR] = 0.156, 95% confidence intervals [CI]: 0.037-0.644) and severe vasospasm (OR = 5.593, 95% CI: 1.372-22.812) were risk factors for severe functional outcomes. This study shows potential therapeutic effect of early and prolonged MH treatment in poor-grade SAH patients. A randomized controlled study with a large number of patients is warranted in the future.