Intraoperative Temperature Research Articles

Intraoperative temperature management during emergency cesarean section: a retrospective observational study.

Intraoperative hypothermia is a common complication during cesarean section (C-section) and associated with the high maternal mortality and morbidity. This study aimed to explore the risk factors associated with the incidence of intraoperative hypothermia in women who underwent emergency C-section deliveries. We retrospectively enrolled women who underwent emergency cesarean deliveries from August 2022 to Dec 2023 at Suzhou Municipal Hospital of Anhui Province. Baseline characteristics, thermal status, and perioperative information were extracted. Hypothermia was defined as the onset of a core temperature below 36°C. Data were compared between patients with and without a hypothermia during surgery. Logistic regression analyses were performed to determine the risk factors for low-temperature-status. Overall, 87 patients were included, and 30 underwent hypothermia during surgery. For women with a normal temperature status, women in the hypothermia group had a lower incidence of receiving active warming methods (52.6% vs. 30%, P = 0.044). In the logistic regression model involving core temperature, a pre-surgery core temperature < 36.5°C (OR 4.22, 95% CI 1.13-15.63, p = 0.032) and a long surgery duration (per 10min, OR 1.97, 95% CI 1.24-3.11, p = 0.004) were associated with a high probability of hypothermia. Administering active warming methods to women can reduce the risk of experiencing a hypothermia during emergency C-sections (OR 0.19, 95% CI 0.05-0.63; p = 0.007). Hypothermia is common in emergency C-section deliveries. It is recommended that active warming methods should be applied to parturient undergoing emergency C-sections more proactively, especially for women who have a low baseline core temperature (< 36.5°C) and are expected to have a long surgery duration.

Perioperative Hypothermia in Surgical Patients: A Retrospective Cohort Analysis at a Busy District General Hospital.

Introduction Perioperative hypothermia is a common yet underreported complication of surgery. It results from various factors, including cold operating theaters, anesthetic effects, environmental exposure, exposed tissues, and the administration of cold intravenous or irrigation fluids. This study aims to determine the incidence of perioperative hypothermia in a district National Health Service hospital to assess the feasibility of a randomized controlled trial (RCT) for interventions to prevent hypothermia. Methods This retrospective study included the data of 200 elective surgical patients at North Manchester General Hospital from June 1, 2022, to August 1, 2022. Inclusion criteria were elective general surgery, urology, breast, and gynecology patients aged 18 to 60 years. Exclusion criteria included emergency cases and patients younger than 18 or older than 60. Temperature measurement data were collected from the anesthesia records of the patients at six phases: preoperative, pre-induction, intraoperative, post-procedure, recovery room, and post-recovery. Data collection included specialty, surgery duration, and the use of intraoperative fluid warmers. Statistical analysis was performed using StatsDirect software (StatsDirect Ltd, Wirral, UK). Results Among the 200 patients, the overall incidence of hypothermia was 4% preoperatively, 5% pre-induction, 12% intraoperatively, 11% postoperatively, 8% in recovery, and 6% post-recovery. Intraoperative hypothermia incidence was significant, given that active warming was applied to patients with preoperative hypothermia. Regression analysis showed no correlation between intraoperative temperature and the use of intraoperative fluid warmers. Pre-induction temperature was the most statistically significant predictor of intraoperative hypothermia. Conclusions This study highlights the need for active interventions to recognize and prevent perioperative hypothermia in elective surgical patients. Active pre-warming of patients, regardless of surgery type and duration, is feasible and potentially beneficial. Future research should include an RCT comparing active and passive warming strategies to evaluate their effectiveness in improving perioperative outcomes.

ThP7.10 - Perioperative Temperature in Relation to Theatre Temperature in Orthopaedic Trauma Patients in a District Hospital in NHS

Abstract Aim To understand the relation between intraoperative hypothermia and theatre temperature in Orthopaedic trauma list. Method Prospective analysis of patients listed in the trauma list at a busy district general hospital in NHS. The data collected included duration of surgery, preoperative temperature, pre induction temperature, intra-operative, post procedure, temperature in recovery and temperature post recovery, and mean ambient theatre temperature. Statistical calculations were performed on StatsDirect3 software. Results A total of 100 patients were included in the study from 1 Aug 2023 to 30 September 2023. Intraoperative hypothermia (core body temperature &amp;lt;= 36) was 21%. Preoperative temperature (p=0.033) and preinduction temperature (p&amp;lt;0.001) was statistically significant factor in influencing the intraoperative temperature. Theatre temperature was an independent predictor of intraoperative hypothermia on regression analysis (p&amp;lt;0.001). Conclusions Theatre temperature of 19.5 to 20.5 °C results in a core body intraoperative temperature of 36.3 to 37.3°C. Temperatures below 19.5 results in higher incidence of hypothermia. Preinduction temperature of 36.4°C results in intraoperative temperature of 36°C and a preinduction temperature of 37.1°C leads to intraoperative temperature of 36.7°C. This indicates that preoperative warming as well as a theatre temperature of 19.5 to 20.5 °C will help in reduction of the intraoperative hypothermia.

EP620 - Incidence of Perioperative hypothermia in elective surgeries at a district hospital in NHS - loop completion

Abstract Aim To investigate the incidence of peri-operative hypothermia (core temperature ≤ 36 ⁰C) in all elective surgical patients at a district hospital in NHS and compare the results to the previous study. To understand the contributing factors to hypothermia in the elective surgical patients. Methods Inadvertent perioperative hypothermia (IPH) is defined as a core body temperature &amp;lt;36.0°C. It is a common consequence of anaesthesia, which increases morbidity and potentially increases mortality. National Institute of Health and Care Excellence (NICE) Guideline 65 which summarises best practice for the prevention and treatment of hypothermia in adults undergoing surgery. Prospective analysis of 100 electively listed surgical patients at NMGH. We prospectively studied all the electively listed general surgery, breast, gynaecology, urology, orthopaedics patients from 1 July 2023 to 1 September 2023. Exclusion criteria – All emergency cases. Pre-operative temperature, pre-induction temperature, intra-operative, post-procedure, temperature in recovery and temperature post recovery were recorded. Temperature measurement was via tympanic or temporal thermometers. All statistical calculations were performed on the StatsDirect3 software. Results Preoperative 36.55, Pre-induction 36.55, Intra-operative 36.5, Postoperative is 36.5, Recovery 36.5 Post recovery is 36.6, Theatre temperature 19.5 Conclusion Statistically significant correlation was observed between the intraoperative temperature and the pre-induction temperature as well as the theatre ambient temperature (p &amp;lt; 0.0001). A theatre temperature of 18 °C has a predicted intraoperative temperature of 34.4 °C and a temperature of 19 °C has a predicted temperature of 36.3 °C. Median pre-induction temperature at NMGH is 36.5 °C and the predicted intraop temp is 36 °C. If the pre-induction temperature raises to 37.2 °C the predicted intraop temperature is 36.6 °C.

Understanding the role of intraoperative hypothermia in perioperative opioid requirements in immediate implant-based breast reconstruction

BackgroundThe relationship between perioperative temperatures and postoperative pain is unknown. The present study investigated the relationship of intraoperative hypothermia and perioperative opioid requirements after immediate implant-based breast reconstruction. MethodsA retrospective chart review was conducted on patients undergoing immediate implant-based breast reconstruction from 2019-2023. Patients were classified into the hypothermic group (majority of procedure < 36.0 °C) or normothermic group (majority of procedure ≥ 36.0 °C). Cumulative inpatient opioid requirements (morphine milli-equivalents [MMEs]) and frequency of patients requiring “high-dose opioids” (≥ 100 MMEs) were collected and compared between groups. ResultsIn total, 536 patients (835 breasts) were included, of which 135 (25.1%) were hypothermic. The hypothermic group had lower mean intraoperative (88.4 vs 99.1 MMEs, P = 0.007) and postoperative (44.2 vs 56.8 MMEs, P = 0.006) than the normothermic group. Mean (B = 14.6, P = 0.004) and nadir (B = 10.4, P = 0.038) intraoperative temperatures directly predicted higher opioid requirements while higher percentages of the procedure time spent under 36 °C (B = -27.6, P = 0.004) predicted lower opioid requirements. The hypothermic group was associated with 66% decreased odds of requiring high-dose opioids after adjusting for differences in patient and operative characteristics (P = 0.007). ConclusionHypothermia is associated with decreased perioperative opioid requirements. Future studies should further investigate ideal temperature thresholds for warming protocols to minimize postoperative pain.

Application value of machine learning models in predicting intraoperative hypothermia in laparoscopic surgery for polytrauma patients

BACKGROUND Hypothermia during laparoscopic surgery in patients with multiple trauma is a significant concern owing to its potential complications. Machine learning models offer a promising approach to predict the occurrence of intraoperative hypothermia. AIM To investigate the value of machine learning model to predict hypothermia during laparoscopic surgery in patients with multiple trauma. METHODS This retrospective study enrolled 220 patients who were admitted with multiple injuries between June 2018 and December 2023. Of these, 154 patients were allocated to a training set and the remaining 66 were allocated to a validation set in a 7:3 ratio. In the training set, 53 cases experienced intraoperative hypothermia and 101 did not. Logistic regression analysis was used to construct a predictive model of intraoperative hypothermia in patients with polytrauma undergoing laparoscopic surgery. The area under the curve (AUC), sensitivity, and specificity were calculated. RESULTS Comparison of the hypothermia and non-hypothermia groups found significant differences in sex, age, baseline temperature, intraoperative temperature, duration of anesthesia, duration of surgery, intraoperative fluid infusion, crystalloid infusion, colloid infusion, and pneumoperitoneum volume (P &lt; 0.05). Differences between other characteristics were not significant (P &gt; 0.05). The results of the logistic regression analysis showed that age, baseline temperature, intraoperative temperature, duration of anesthesia, and duration of surgery were independent influencing factors for intraoperative hypothermia during laparoscopic surgery (P &lt; 0.05). Calibration curve analysis showed good consistency between the predicted occurrence of intraoperative hypothermia and the actual occurrence (P &gt; 0.05). The predictive model had AUCs of 0.850 and 0.829 for the training and validation sets, respectively. CONCLUSION Machine learning effectively predicted intraoperative hypothermia in polytrauma patients undergoing laparoscopic surgery, which improved surgical safety and patient recovery.

Intraoperative Ablation Control Based on Real-Time Necrosis Monitoring Feedback: Numerical Evaluation.

Ablation therapy is a type of minimally invasive treatment, utilized for various organs including the brain, heart, and kidneys. The accuracy of the ablation process is critically important to avoid both insufficient and excessive ablation, which may result in compromised efficacy or complications. The thermal ablation is formulated by two theoretical models: the heat transfer (HT) and necrosis formation (NF) models. In modern medical practices, feed-forward (FF) and temperature feedback (TFB) controls are primarily used as ablation control methodologies. FF involves pre-therapy procedure planning based on previous experiences and theoretical knowledge without monitoring the intraoperative tissue response, hence, it can't compensate for discrepancies in the assumed HT or NF models. These discrepancies can arise due to individual patient's tissue characteristic differences and specific environmental conditions. Conversely, TFB control is based on the intraoperative temperature profile. It estimates the resulting heat damage based on the monitored temperature distribution and assumed NF model. Therefore, TFB can make necessary adjustments even if there is an error in the assumed HT model. TFB is thus seen as a more robust control method against modeling errors in the HT model. Still, TFB is limited as it assumes a fixed NF model, irrespective of the patient or the ablation technique used. An ideal solution to these limitations would be to actively monitor heat damage to the tissue during the operation and utilize this data to control ablation. This strategy is defined as necrosis feedback (NFB) in this study. Such real-time necrosis monitoring modalities making NFB possible are emerging, however, there is an absence of a generalized study that discusses the integration and quantifies the significance of the real-time necrosis monitor techniques for ablation therapy. Such an investigation is expected to clarify the universal principles of how these techniques would improve ablation therapy. In this study, we examine the potential of NFB in suppressing errors associated with the NF model as NFB is theoretically capable of monitoring and suppressing the errors associated with the NF models in its closed control loop. We simulate and compare the performances of TFB and NFB with artificially generated modeling errors using the finite element method (FEM). The results show that NFB provides more accurate ablation control than TFB when NF-oriented errors are applied, indicating NFB's potential to improve the ablation control accuracy and highlighting the value of the ongoing research to make real-time necrosis monitoring a clinically viable option.

Impact of Intraoperative Hypothermia on Incidence of Infection in Implant-Based Breast Reconstruction in Pakistan

Background: Intraoperative hypothermia, an unintentional drop in core body temperature during surgery, poses a significant risk in implant-based breast reconstruction. This condition can weaken immune function, slow blood flow, and increase the risk of postoperative infections. Objective: To evaluate the impact of intraoperative hypothermia on the incidence of infections in patients undergoing implant-based breast reconstruction in Pakistan. Methods: This retrospective cohort study was conducted at Jinnah Sindh Medical University from January 2023 to November 2023. The study included 195 female breast cancer patients aged 18 and above who underwent implant-based breast reconstruction. Patients with pre-existing infections, concurrent chemotherapy or radiotherapy during the perioperative period, and incomplete medical records were excluded. Detailed patient demographics, surgical specifics, and intraoperative temperature control measures were recorded. Patients were categorized into normothermic (core body temperature ≥ 36°C) and hypothermic (core body temperature &lt;36°C) groups. Infection data post-surgery were collected through clinical assessments, blood tests, and imaging techniques. Data were analyzed using SPSS version 25, with descriptive statistics, chi-square tests for categorical variables, and independent t-tests for continuous variables. A p-value of less than 0.05 was considered statistically significant. Ethical approval was obtained, and informed consent was secured from all participants. Results: The mean age of patients was 45.23±3.45 years in the normothermic group and 46.01±2.89 years in the hypothermic group. The hypothermic group had a slightly higher average BMI (25.1 kg/m²) compared to the normothermic group (24.5 kg/m²). Total infections were observed in 26.3% of the hypothermic group versus 10% in the normothermic group. Superficial infections were reported in 12.6% of hypothermic patients compared to 6% of normothermic patients. Deep infections were more prevalent in the hypothermic group at 13.7%, compared to 4% in the normothermic group. The univariate odds ratio (OR) for intraoperative hypothermia was 3.2 (95% CI: 1.5-6.8) and the multivariate OR was 3.0 (95% CI: 1.3-6.5), both with a p-value of less than 0.01. Conclusion: Intraoperative hypothermia significantly increases the risk of postoperative infections in patients undergoing implant-based breast reconstruction. Effective temperature management strategies, such as preoperative warming and the use of intraoperative warming devices, are crucial to reducing infection rates and improving surgical outcomes

Normothermia to Decrease Surgical Site Infection Risk: Silver Bullet or Fool's Gold? A Retrospective Cohort Study.

Surgical site infection (SSI) is the leading cause of nosocomial infections among surgical patients in the United States. Currently, there is compelling evidence suggesting that temperature dysregulation in surgical patients may be a risk factor for the development of SSI. We examined the relationship between perioperative hypothermia (PH) and SSI in a population of surgical patients with diabetes mellitus (DM). This retrospective cohort review was conducted on patients with a history of DM undergoing orthopaedic surgery at our institution between May 1, 2018, and April 1, 2022. Inclusion criteria were age older than 15 years, a history of DM or recent hemoglobin A1c concentration of ≥6.5%, and operation of at least 60 minutes under general anesthesia. Perioperative hypothermia was defined as an intraoperative temperature ≤ 35.5°C. Continuous variables were compared using the t-test and Wilcoxon rank-sum test. Categorical variables were compared using the chi-squared test. We constructed a multivariable logistic regression model to estimate SSI risk while controlling for demographic variables. A total of 236 patients were included in the final analysis. The overall incidence of SSI was 5.93%. 99 patients (42%) experienced PH. No difference was observed in the risk of SSI between the normothermic and hypothermic cohorts. Among the 99 patients who experienced PH, increasing HbA1c was associated with increasing risk of SSI (OR = 2.39, 95% CI = 1.12 to 5.32, P-value = 0.0222). The multivariable logistic regression model had good discriminatory ability (c-statistic 0.74, 95% CI: 0.61 to 0.89) and good predictive accuracy (sensitivity 64%, specificity 73%). PH is not an independent risk factor of SSI. However, in the presence of elevated HbA1c, PH may more than double the risk of SSI. Perioperative hypothermia may be an additive risk factor in the setting of poor glycemic control and potentially in the setting of other known risk factors.

Related factors of perioperative low body temperature and incidence of postoperative shivering in patients undergoing complex percutaneous nephrolithotomy and the effect analysis of composite insulation nursing intervention

This study aimed to analyze the factors associated with intraoperative hypothermia and postoperative shivering rates in patients undergoing complex percutaneous nephrolithotomy (PCNL) and investigate the effects of combined insulation nursing intervention. A total of 168 patients were included, with 103 patients in the control (Ctrl) group receiving routine care and 65 patients in the nursing (Nur) group receiving combined insulation nursing intervention measures. General information, surgical data, temperature, intraoperative hypothermia incidence, postoperative shivering, and complication rates were statistically analyzed between the two groups. Patient temperature, blood pressure, and blood gas indicators including pH value, bicarbonate, and lactate levels were recorded at admission (T0), before anesthesia (T1), 30 min after spinal-epidural combined anesthesia (T2), 60 min (T3), 90 min (T4), 120 min (T5), and postoperatively (T6). The results demonstrated that the average intraoperative temperature of patients in the Nur group was significantly higher than that of the Ctrl group (P < 0.001), and their incidence of hypothermia was significantly lower than that of the Ctrl group (P < 0.01). Additionally, the Nur group exhibited shorter recovery time (18.36 ± 3.58 min), extubation time (28.01 ± 3.12 min), and length of hospital stay (8.45 ± 2.14 days) compared to the Ctrl group (P < 0.05). The incidence of postoperative shivering was 4.62 %, significantly lower than that of the Ctrl group (P < 0.001). Multifactorial analysis revealed that age ≥60 years, stone diameter ≥3.0 cm, irrigation volume ≥3000 mL, nursing intervention measures, and surgical duration were the main factors influencing the occurrence of intraoperative hypothermia. Age ≥60 years, nursing intervention measures, surgical duration, and intraoperative temperature<36 °C are identified as major risk factors for postoperative shivering. This indicates that specialized nursing care and combined insulation nursing intervention measures in patients undergoing complex percutaneous nephrolithotomy contribute to reducing the incidence of intraoperative hypothermia and postoperative shivering. It is recommended to promptly address the risk factors associated with hypothermia and shivering during and after surgery to mitigate the risk of perioperative complications.

Magnitude and associated factors of intraoperative hypothermia among pediatric patients undergoing elective surgery at Ayder Comprehensive Specialized Hospital 2023: prospective observational cross-sectional study Tigray, Ethiopia.

Hypothermia is characterized by a drop in core body temperature of less than 36°C. It occurs frequently throughout the operating period and affects surgical patient outcomes differently in terms of morbidity and mortality. Because of coagulopathy, metabolic acidosis, multiple organ failure, hemodynamic instability, and infections, a core temperature below 34°C is strongly associated with mortality. This study aimed to assess the magnitude and associated factors of intraoperative hypothermia in pediatric patients undergoing elective surgery at the Ayder Comprehensive Specialized Hospital. A prospective observational cross-sectional study was conducted on 399 pediatric patients undergoing elective surgery at Ayder Comprehensive Specialized Hospital in Tigray, Ethiopia, from 1 May 2023, to 30 July 2023. Participants in the study were selected by a systematic random sampling technique. The data collection procedure was chart review and intraoperative temperature measurement, and the collected data were analyzed by SPSS version 23. The independent variables were analyzed using binary and multi-logistic regression. The odds ratio, 95% CI, and p value of less than 0.05 were considered statistical significance. The magnitude of intraoperative hypothermia was 52.9%. Neonate and infant [adjusted odds ratio (AOR): 6, 95% CI: 3.7, 9.8], (AOR=4.5, 95% CI: 2.9, 7) respectively, volume of fluid administered greater than half-liter [AOR: 4.37, (95% CI, 3, 6.4)], patients who underwent surgery during the morning [AOR: 5.3, (95% CI: 3.8, 7.4)], and duration of surgery and anesthesia greater than 120 minutes [AOR: 2.7, (95% CI, 1.8, 4)] and (AOR=3.4, 95% CI, 2.4, 4.9], respectively, were factors significantly associated with intraoperative hypothermia. This study revealed a high magnitude of intraoperative hypothermia among pediatric patients. Being neonates and infants, having a cold volume of IV fluid administered greater than half a liter, entering surgery during the morning, the duration of surgery, and the anesthesia time were significantly associated with intraoperative hypothermia. The authors would like to advise anesthetists to use warm intravenous fluids, calculate IV fluids, and maintain room temperature.

AB097. SOH24AB_039. Intra-operative temperature monitoring: an audit of compliance to the national standard at University Hospital Limerick

AB097. SOH24AB_039. Intra-operative temperature monitoring: an audit of compliance to the national standard at University Hospital Limerick

Assessing the Influence of Intraoperative Core Body Temperature on Postoperative Venous Thromboembolism after Abdominal Wall Reconstruction.

Venous thromboembolism (VTE) is a dangerous postoperative complication after abdominal wall reconstruction (AWR). Intraoperative core body temperature has been associated with thrombotic events in other surgical contexts. This study examines the effects of intraoperative temperature on VTE rate after AWR. A retrospective study was performed on AWR patients. Cohorts were defined by postoperative 30-day VTE. Intraoperative core body temperature was recorded as the minimum, maximum, and mean intraoperative temperatures. Study variables were analyzed with logistic regression and cutoff analysis to assess for association with VTE. In total, 344 patients met inclusion criteria. Fourteen patients were diagnosed with 30-day VTE for an incidence of 4.1%. The VTE cohort had a longer median inpatient stay (8 days versus 5 days, P < 0.001) and greater intraoperative change in peak inspiratory pressure (3 mm H2O versus 1 mm H2O, P = 0.01) than the non-VTE cohort. Operative duration [odds ratio (OR) = 1.32, P = 0.01], length of stay (OR = 1.07, P = 0.001), and intraoperative PIP difference (OR = 1.18, P = 0.045) were significantly associated with 30-day VTE on univariable regression. Immunocompromised status (OR = 4.1, P = 0.023; OR = 4.0, P = 0.025) and length of stay (OR = 1.1, P < 0.001; OR = 1.1, P < 0.001) were significant predictors of 30-day VTE on two multivariable regression models. No significant associations were found between temperature metrics and 30-day VTE on cutoff point or regression analysis. Intraoperative core body temperature did not associate with 30-day VTE after AWR, though operative duration, length of stay, immunocompromised status, and intraoperative PIP difference did. Surgeons should remain mindful of VTE risk after AWR, and future research is warranted to elucidate all contributing factors.

Thermal Field Monitoring When Exposing Soft Tissues to Low Temperatures: Thermography Prospects and Limitations

The review analyzes the existing tools for monitoring the dynamics of thermal fi elds when exposing the soft tissues to low temperatures. Features of contact and non-contact temperature measurements have been considered, their capabilities and limitations have been noted. There was substantiated the need to develop the procedures of intra-operative temperature control. Special attention has been paid to the non-contact non-invasive infrared thermography. This method has been shown to be applied for intra-operative monitoring of the movement of the ice lump edge on the surface of tissues, detection of a disordered thermal symmetry of the ice spot, thermal fi eld dynamics on the surface of tissues inside and outside the area of the operative zone. However, thermal imaging control of the dynamics of the primary necrosis zone and the ice ball edge in the volume of tissues is possible only under certain parameters of cryoimpact, for example, with a short-term cooling of tissues with a quasi-point nitrogen cryoapplicator. The possibility of using thermography at other stages of cryosurgery is also considered, i. e. as the method of additional diagnosis at the stage of surgery planning, as well as during the post-surgery period to control healing, scarring, etc.

Comparison of prewarming plus intraoperative warming with intraoperative warming alone in patients undergoing minimally invasive thoracic or abdominal surgery: A systematic review and meta-analysis.

Prewarming has been recommended to reduce intraoperative hypothermia. However, the evidence is unclear. This review examined if prewarming can prevent intraoperative hypothermia in patients undergoing thoracoscopic and laparoscopic surgeries. PubMed, CENTRAL, Web of Science, and Embase databases were searched for randomized controlled trials (RCTs) up to 15th January 2024. The primary outcome of interest was the difference in intraoperative core temperature. The secondary outcomes were intraoperative hypothermia (<36°) and postoperative shivering. Seven RCTs were eligible. Meta-analysis showed that intraoperative core temperature was significantly higher at the start or within 30mins of the start of the surgery (MD: 0.32 95% CI: 0.15, 0.50 I2 = 94% p = 0.0003), 60 mins after the start of the surgery (MD: 0.37 95% CI: 0.24, 0.50 I2 = 81% p<0.00001), 120 mins after the start of the surgery (MD: 0.34 95% CI: 0.12, 0.56 I2 = 88% p = 0.003), and at the end of the surgery (MD: 0.35 95% CI: 0.25, 0.45 I2 = 61% p<0.00001). The incidence of shivering was also significantly lower in the prewarming group (OR: 0.18 95% CI: 0.08, 0.43 I2 = 0%). Prewarming was also associated with a significant reduction in the risk of hypothermia (OR: 0.20 95% CI: 0.10, 0.41 I2 = 0% p<0.0001). The certainty of the evidence assessed by GRADE was "moderate" for intraoperative core temperatures at all time points and "low" for minimal intraoperative core temperature, shivering, and hypothermia. Moderate to low-quality evidence shows that prewarming combined with intraoperative warming, as compared to intraoperative warming alone, can improve intraoperative temperature control and reduce the risk of hypothermia and shivering in patients undergoing thoracoscopic and laparoscopic procedures.

Utility of heparin-binding protein following cardiothoracic surgery using cardiopulmonary bypass

Cardiothoracic surgery using cardiopulmonary bypass (CPB) triggers an inflammatory state that may be difficult to differentiate from infection. Heparin-binding protein (HBP) is a candidate biomarker for sepsis. As data indicates that HBP normalizes rapidly after cardiothoracic surgery, it may be a suitable early marker of postoperative infection. We therefore aimed to investigate which variables influence postoperative HBP levels and whether elevated HBP concentration is associated with poor surgical outcome. This exploratory, prospective, observational study enrolled 1475 patients undergoing cardiothoracic surgery using CPB, where HBP was measured at ICU arrival. Patients with HBP in the highest tercile were compared to remaining patients. Multivariable logistic regressions were performed to identify factors predictive of elevated HBP and 30-day mortality. Overall median HBP was 30.0 ng/mL. Patients undergoing isolated CABG or surgery with CPB-duration ≤ 60 min had a median HBP of 24.9 ng/mL and 23.2 ng/mL, respectively. Independent predictors of elevated postoperative HBP included increased EuroSCORE, prolonged CPB-duration and high intraoperative temperature. Increased HBP was an independent predictor of 30-day mortality. This study confirms the promising characteristics of HBP as a biomarker for identification of postoperative sepsis, especially after routine procedures. Further studies are required to investigate whether HBP may detect postoperative infections.

WTP5.1 Perioperative hypothermia in elective surgical patients

Abstract Introduction Perioperative hypothermia is an under-reported, yet well recognized complication of surgery. Normal thermoregulatory mechanisms are disrupted in anesthetized patients. Up to 70% of surgical patients develop perioperative hypothermia, with serious consequences including coagulopathy, sepsis and cardiac events. Methods In this single centre study, we collected prospective data from 100 elective operations in urology, gynaecology, general and breast surgery. The pre-operative, pre-induction, intraoperative, post-procedure and in recovery temperatures (in Celsius) were recorded. Any temperature below the 36°C was regarded as hypothermia and the total incidence of hypothermia during all the 5 phases were calculated. Results Incidences of hypothermia in pre-operative, pre-induction, intraoperative, post-procedure and in-recovery were 4 %, 5%, 12 %, 11 %, 8 % and 6 % respectively. Multiple regression analysis of pre-operative, pre-induction and intra-operative temperatures resulted in a p value of 0.237 for pre-operative temperature and 0.000032577 for pre-induction temperatures respectively. This suggests that pre-induction temperature was the most statistically significant parameter for intra-operative hypothermia. Furthermore, regression analysis predicted the intra-operative temperature for a given pre-induction temperature. Regression analysis line fit plot between preinduction and intra-operative temperatures predicted that for intraoperative temperature to be 36.74 °C, mean preinduction temperature is to be raised to 37.2 °C. Conclusion This study highlights the incidence of intraoperative hypothermia and need for active interventions to prevent the same. It paves the way for a single blinded randomized controlled trial for comparing different modalities to pre-warm patients and prevent intraoperative hypothermia.

Multivariate analysis and nursing intervention strategies for intraoperative pressure ulcers in patients undergoing craniocerebral microsurgery

ObjectiveThis study aimed to investigate the various influencing factors for intraoperative pressure sores in patients with craniocerebral microsurgery and provide nursing intervention strategies for surgical pressure sores in a clinical operating room. MethodsThis was a case–control study on 2157 patients who underwent craniocerebral microsurgery in the craniocerebral department of the hospital between November 2021 and November 2022. Of these, 62 patients with intraoperative pressure sores were compared with 248 patients without pressure sores during the same period using a 1:4 case–control method. A logistic regression model was used to analyze the effect of possible factors on pressure sores in an operating room. ResultsThe incidence of pressure sores in craniocerebral microsurgery was 2.87%. The logistic regression analysis showed that skin at the pressure site [odds ratio (OR) = 1.759, 95% confidence interval (CI): 1.137–2.721], surgical position (OR = 1.727, 95% CI: 1.338–2.228), intraoperative body temperature (OR = 2.229, 95% CI: 1.229–4.042), and surgical time (OR = 2.009, 95% CI: 1.221–3.303) were independent factors for the occurrence of intraoperative pressure sores. ConclusionsThe high-risk factors for pressure sores in craniocerebral microsurgery included fasting time, surgical position, intraoperative temperature, and skin at the pressure site. Targeted attention and protection had a positive effect in preventing intraoperative pressure sores in patients who underwent craniocerebral microsurgery.

Modified intraoperative temperature management prevents prolonged length of stay after head and neck surgery with free flap reconstruction

The present study aimed to investigate the association between intraoperative body temperature and prolonged length of stay (PLOS) after free flap reconstruction. A total of 753 patients who underwent head and neck surgery with free flap reconstruction were collected and randomly assigned into primary and validation cohorts. In the primary cohort, univariable and multivariable analyses were conducted to evaluate associations between intraoperative time-weighted (TW) temperature (TW average [TWA] temperature, TW hypothermia and TW hyperthermia) and PLOS. Nomograms were developed with and without intraoperative TW temperature, and validated in the validation cohort. Severe intraoperative TW hypothermia (OR = 1.004; 95% CI: 1.000, 1.007; p = 0.032) was identified as an independent risk factor for PLOS. Intraoperative TWA temperature and TW hypothermia showed linear related predictive effect for PLOS. The nomogram incorporating intraoperative TW temperature showed higher C-index (0.652, 95% CI: 0.591, 0.713) and improved net reclassification improvement for non-event (0.277, 95% CI: 0.118, 0.435; p < 0.001). Lower TWA temperature with mild TW hypothermia had a preventive effect on PLOS with a linear association, which may provide a modified range for intraoperative temperature management. The proposed nomogram incorporating intraoperative TW temperature could be used to develop personalized preventive strategies for PLOS after free flap reconstruction. IRB numberSYSEC-KY-KS-2022-037. Clinical trial registration numberNot applicable.

The influence of operating room temperature and humidity on surgical site infection: A multisite ACS-NSQIP analysis

BackgroundLiterature evaluating intraoperative temperature/humidity and risk of surgical site infection (SSI) is lacking. MethodsAll operations at three centers reported to the ACS-NSQIP were reviewed (2016–2020); ambient intraoperative temperature (⁰F) and relative humidity (RH) were recorded in 15-min intervals. The primary endpoint was superficial SSI, which was evaluated with multi-level logistic regression. Results14,519 operations were analyzed with 179 SSIs (1.2%). The lower/upper 10th percentiles for temperature and RH were 64.4/71.4 °F and 33.5/55.5% respectively. Low or high temperature carried no significant increased risk for SSI (Low ⁰F OR = 0.95, 95% CI 0.51–1.77, P = 0.86; High ⁰F OR = 1.13, 95% CI = 0.69–1.86, P = 0.63). This was also true for low and high RH (Low RH OR = 0.96, 95% CI 0.58–1.61, p = 0.88; High RH OR = 0.61, 95% CI = 0.33–1.14, P = 0.12). Analysis of combined temperature/humidity showed no increased risk for SSI. ConclusionSignificant deviations in intraoperative temperature/humidity are not associated with increased risk of SSI.