A retrospective data analysis on prevalence and risk factors for hypothermia among sick neonates at presentation to the neonatal intensive care unit of the Tamale Teaching Hospital.

Neonatal hypothermia, defined as an axillary temperature of <36.5C in a neonate, is common in neonatal intensive care units and is almost universal across all geographic and climatic regions of the world. This is even though environmental temperature is a known risk factor for its occurrence. We conducted a retrospective study in the Neonatal Intensive Care Unit of the Tamale Teaching Hospital (TTH) to document the prevalence and risk factors associated with hypothermia at presentation to the hospital. The study spanned the period from January 2019 to December 2019 and involved all neonates with axillary temperature documented at the time of admission. The prevalence of neonatal hypothermia in this study was 54.76%. Hypothermia was most common in neonates diagnosed with meconium aspiration syndrome (87/105, 82.86%), prematurity and low birth weight (575/702, 81.91%), and birth asphyxia (347/445, 77.98%). Neonates who were delivered vaginally were less likely to develop hypothermia compared to those delivered via Cesarean section. Inborn neonates (delivered in TTH) were 3.2 times more likely to be hypothermic when compared to those who were delivered at home. Neonates with low birth weight and APGAR scores < 7 at 1 and 5 minutes were more likely to be hypothermic. The dry season was found to be protective against hypothermia when compared to the rainy season. The overall mortality rate was 13.68% and the mortality in the subgroup with hypothermia at presentation was 18.87%. Our study documented a high prevalence of hypothermia with higher rates in neonates requiring intervention at birth. It is therefore crucial for perinatal care providers to adhere to the warm chain precautions around the time of birth.

The relationship between intraoperative hypothermia and postoperative delirium: The PNDRFAP study.

OBJECTIVE: Our study aimed to investigate the correlation between intraoperative hypothermia and postoperative delirium (POD) in patients undergoing general anesthesia for gastrointestinal surgery. METHODS: The study comprised 750 participants from the Perioperative Neurocognitive Disorder Risk Factor and Prognosis (PNDRFAP) study database, which ultimately screened 510 individuals in the final analysis. Preoperative cognitive function was evaluated using the Mini-Mental State Examination (MMSE). The occurrence of POD was determined using the Confusion Assessment Method, and the severity of POD was evaluated using the Memorial Delirium Assessment Scale. Logistic regression was employed to scrutinize the association between intraoperative hypothermia and the incidence of POD, and the sensitivity analysis was conducted by introducing adjusted confounding variables. Decision curves and a nomogram model were utilized to assess the predictive efficacy of intraoperative hypothermia for POD. Mediation analysis involving 10,000 bootstrapped iterations was employed to appraise the suggested mediating effect of numeric rating scale (NRS) scores at 24 and 48 h post-surgeries. The receiver-operating characteristic (ROC) was utilized to evaluate the effectiveness of intraoperative hypothermia in predicting POD. RESULTS: In the PNDRFAP study, the occurrence of POD was notably higher in the intraoperative hypothermia group (62.2%) compared to the intraoperative normal body temperature group (9.8%), with an overall POD incidence of 17.6%. Logistic regression analysis, adjusted for various confounding factors (age [40-90], gender, education, MMSE, smoking history, drinking history, hypertension, diabetes, and the presence of cardiovascular heart disease), demonstrated that intraoperative hypothermia significantly increased the risk of POD (OR = 4.879, 95% CI = 3.020-7.882, p < .001). Mediation analyses revealed that the relationship between intraoperative hypothermia and POD was partially mediated by NRS 24 h after surgery, accounting for 14.09% of the association (p = .002). The area under the curve of the ROC curve was 0.685, which confirmed that intraoperative hypothermia could predict POD occurrence to a certain extent. Decision curve and nomogram analyses, conducted using the R package, further substantiated the predictive efficacy of intraoperative hypothermia on POD. CONCLUSION: Intraoperative hypothermia may increase the risk of POD, and this association may be partially mediated by NRS scores 24 h after surgery.

Impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery.

BACKGROUND: This study aimed to investigate the impact of intraoperative hypothermia on the recovery period of anesthesia in elderly patients undergoing abdominal surgery. METHODS: A prospective observational study was conducted based on inclusion and exclusion criteria. A total of 384 elderly patients undergoing abdominal surgery under general anesthesia were enrolled in a grade A tertiary hospital in Chengdu, Sichuan Province from October 2021 and October 2022. After anesthesia induction, inflatable warming blankets were routinely used for active heat preservation, and nasopharyngeal temperature was monitored to observe the occurrence of intraoperative hypothermia. Patients were divided into hypothermia group and nonhypothermia group according to whether hypothermia occurred during the operation. Anesthesia recovery time and the incidence of adverse events or unwanted events during anesthesia recovery between the two groups were compared. RESULTS: The numbers (percentage) of 384 patients who underwent abdominal surgery developed intraoperative hypothermia occurred in 240 (62.5%) patients, all of whom had mild hypothermia. There were statistically significant differences between mild hypothermia after active warming and nonhypothermia in the occurrence of shivering (χ2 = 5.197, P = 0.023) and anesthesia recovery time (Z = -2.269, P = 0.02) in elderly patients undergoing abdominal surgery during anesthesia recovery, and there were no statistically significant differences in hypoxemia, nausea or vomiting, hypertension, hypokalemia, hypocalcemia, analgesic drug use,postoperative wound infection or postoperative hospitalization days. CONCLUSIONS: The incidence of intraoperative mild hypothermia after active warming was high in elderly patients who underwent abdominal surgery. Mild hypothermia increased the incidence of shivering and prolonged anesthesia recovery time in elderly patients undergoing abdominal surgery.

Association of hypermagnesemia at birth and admission hypothermia in pre-term infants: A secondary analysis of a prospective cohort study.

BACKGROUND: Hypothermia on admission is associated with increased mortality in preterm infants. Drugs administered to pregnant women is implicated in its occurrence. Since magnesium sulfate has a myorelaxant effect, we aimed evaluating the association of hypermagnesemia at birth and admission hypothermia (axillary temperature <36.5°C) in preterm infants. METHODS: We performed a secondary analysis of a prospective cohort study database including inborn infants <34 weeks, without congenital malformations. Hypermagnesemia was considered if the umbilical magnesium level > 2.5 mEq/L. Maternal and neonatal variables were used to adjust the model, submitted to the multivariate hierarchical modelling process. RESULTS: We evaluated 249 newborns with median birth weight and gestational age of 1375 (IQR 1020-1375) g and 31 (IQR 28-32) weeks, respectively. Hypermagnesemia occurred in 28.5% and admission hypothermia occurred in 28.9%. In the univariate analysis, the following variables were identified as being associated with admission hypothermia: hypermagnesemia (OR 3.71; CI 2.06-6.68), resuscitation (OR 2.39; CI 1.37-4.19), small to gestational age (OR 1.91; CI1.03-3.53), general anesthesia (OR 3.34; CI 1.37-8.13), birth weight (OR 0.998; CI 0.998-0.999) and gestational age (OR 0.806; CI 0.725-0.895). In the hierarchical regression model, hypermagnesemia remained independent associated with admission hypothermia (OR 3.20; CI 1.66-6.15), as well as birth weight (OR 0.999; CI 0.998-0.999) and tracheal intubation (3.83; CI 1.88-7.80). CONCLUSION: Hypermagnesemia was associated with an increased risk of admission hypothermia, as did tracheal intubation and lower birth weight.

Clinical Characteristics, Etiology, and Outcomes of Hypothermia in Well-appearing Children Referred to the Emergency Department.

BACKGROUND: Hypothermia, as a sign of serious bacterial infection (SBI) in children and infants older than 90 days is poorly characterized, especially in the post-pneumococcal vaccine era. OBJECTIVES: To assess the prevalence of SBI in children and infants presenting to the pediatric emergency department (PED) with reported or documented hypothermia. METHODS: Retrospective data analysis was conducted of all well-appearing children aged 0-16 years who presented with a diagnosis of hypothermia at two tertiary PEDs from 2010 to 2019. RESULTS: The study comprised 99 children, 15 (15.2%) age 0-3 months, 71 (71.7%) 3-36 months, and 13 (13.1%) > 36 months. The youngest age group had increased length of stay in the hospital (P < 0.001) and increased rates of pediatric intensive care unit admissions (P < 0.001). Empirical antibiotic coverage was initiated in 80% of the children in the 0-3 months group, 21.1% in the 3-36 months group, and 15.4% in > 36 months (P < 0.001). Only one case of SBI was recorded and no bacteremia or meningitis. Hypothermia of unknown origin was the most common diagnosis in all age groups (34%, 42%, 46%), respectively, followed by bronchiolitis (26%) and hypoglycemia (13.3%) for 0-3 month-old children, unspecified viral infection (20%) and otitis media (7%) for 3-36-month old, and unspecified viral infection (23%) and alcohol intoxication (15.2%) in > 36 months. CONCLUSIONS: There is a low incidence of SBI in well-appearing children presenting to the PED with hypothermia and a benign course and outcome in those older than 3 months.

Predicting Serious Bacterial Infections Among Hypothermic Infants in the Emergency Department.

BACKGROUND: There is insufficient evidence to guide the initial evaluation of hypothermic infants. We aimed to evaluate risk factors for serious bacterial infections (SBI) among hypothermic infants presenting to the emergency department (ED). METHODS: We conducted a multicenter case-control study among hypothermic (rectal temperature <36.5°C) infants ≤90 days presenting to the ED who had a blood culture collected. Our outcome was SBI (bacteremia, bacterial meningitis, and/or urinary tract infection). We performed 1:2 matching. Historical, physical examination and laboratory covariables were determined based on the literature review from febrile and hypothermic infants and used logistic regression to identify candidate risk factors. RESULTS: Among 934 included infants, 57 (6.1%) had an SBI. In univariable analyses, the following were associated with SBI: age > 21 days, fever at home or in the ED, leukocytosis, elevated absolute neutrophil count, thrombocytosis, and abnormal urinalysis. Prematurity, respiratory distress, and hypothermia at home were negatively associated with SBI. The full multivariable model exhibited a c-index of 0.91 (95% confidence interval: 0.88-0.94). One variable (abnormal urinalysis) was selected for a reduced model, which had a c-index of 0.82 (95% confidence interval: 0.75-0.89). In a sensitivity analysis among hypothermic infants without fever (n = 22 with SBI among 116 infants), leukocytosis, absolute neutrophil count, and abnormal urinalysis were associated with SBI. CONCLUSIONS: Historical, examination, and laboratory data show potential as variables for risk stratification of hypothermic infants with concern for SBI. Larger studies are needed to definitively risk stratify this cohort, particularly for invasive bacterial infections.

Effect of 10 Minutes of Prewarming and Prewarmed Intravenous Fluid Administration on the Core Temperature of Patients Undergoing Transurethral Surgery under General Anesthesia.

Background: Patients undergoing transurethral urologic procedures using bladder irrigation are at increased risk of perioperative hypothermia. Thirty minutes of prewarming prevents perioperative hypothermia. However, its routine application is impractical. We evaluated the effect of 10 minutes of prewarming combined with the intraoperative administration of warmed intravenous fluid on patients' core temperature. Methods: Fifty patients undergoing transurethral bladder or prostate resection under general anesthesia were included in this study and were randomly allocated to either the control group or the prewarming group. Patients in the prewarming group were warmed for 10 minutes before anesthesia induction with a forced-air warming device and received warmed intravenous fluid during operations. The patients in control group did not receive preoperative forced-air warming and were administered room-temperature fluid. Participants' core body temperature was measured on arrival at the preoperative holding area (T0), on entering the operating room, immediately after anesthesia induction, and in 10-minute intervals from then on until the end of the operation (Tend), on entering PACU, and in 10-minute intervals during the postanesthesia care unit stay. The groups' incidence of intraoperative hypothermia, change in core temperature (T0 - Tend), and postoperative thermal comfort were compared. Results: The incidence of hypothermia was 64% and 29% in the control group and prewarming group, respectively (P = 0.015). Change in core temperature was 0.93 ± 0.3 °C and 0.55 ± 0.4 °C in the control group and prewarming group, respectively (P = 0.0001). Thermal comfort was better in the prewarming group (P = 0.004). Conclusions: Ten minutes of prewarming combined with warmed intravenous fluid significantly decreased the incidence of intraoperative hypothermia and resulted in better thermal comfort in patients undergoing transurethral urologic surgery under general anesthesia.

Comparison of the incidence of inadvertent perioperative hypothermia between general anesthesia and interscalene brachial plexus block in shoulder arthroscopy: A randomized prospective study.

INTRODUCTION: Inadvertent perioperative hypothermia (IPH), defined as core body temperature below 36°C, is associated with various complications. Shoulder arthroscopy is a risk factor of IPH. This study aimed to compare the incidence of IPH between general anesthesia (GA) and interscalene brachial plexus block (ISBPB) for shoulder arthroscopy. METHOD: Patients scheduled for shoulder arthroscopy were prospectively enrolled and randomly assigned to GA or ISBPB groups. The body temperature of the patients was measured from baseline to the end of anesthesia and in the post-anesthetic care unit to compare the incidence of IPH. RESULTS: Of the 114 patients initially identified, 80 were included in the study (GA = 40, ISBPB = 40). The incidence of IPH differed significantly between the groups, with GA at 52.5% and ISBPB at 30.0% (P = .04). Profound IPH (defined as < 35.0°C) occurred in 2 patients with GA. Upon arrival at the post-anesthesia care unit, the GA group exhibited a significantly lower mean body temperature (35.9 ±â€…0.6°C) than the ISBPB group (36.1 ±â€…0.2°C, P = .04). CONCLUSION: The incidence of IPH in the GA group was higher than that in the ISBPB group during shoulder arthroscopy, suggesting that ISBPB may be a preferable anesthetic technique for reducing risk of IPH in such procedures.

Maternal hypothermia during elective caesarean delivery: A prospective observational study.

BACKGROUND: Patients undergoing caesarean delivery are at risk of developing unintended perioperative hypothermia, defined as a core temperature <36.0°C. Most previous studies of core temperature in caesarean delivery patients have not been conducted with accurate measurements for the complete perioperative period. Therefore, we conducted a prospective observational study to identify the incidence and duration of pre- and post-operative maternal hypothermia with a high accuracy continuous temperature monitoring system. METHODS: Women ≥18 years old presenting for elective caesarean delivery under spinal anaesthesia were invited to participate in the study. The primary outcomes were the incidence and duration of perioperative maternal hypothermia (<36.0°C). Maternal core temperatures were measured with the non-invasive zero-heat-flux thermometer (Bair Hugger Temperature Monitoring System, 3M) throughout the perioperative course. RESULTS: A total of 40 participants were recruited to the study. The incidence of perioperative hypothermia was 32.5%, with a duration of 77 ± 40 min (mean ± standard deviation). The hypothermic patients had similar core temperature as the normothermic patients at baseline preoperatively, but significantly lower temperature at operating room arrival and during the remaining study period. Forty percent of all patients reported thermal discomfort and felt cold on admission to post anaesthesia care unit, whereas 33% had shivering. Neither thermal discomfort nor shivering were associated with hypothermia. CONCLUSION: In the present study almost a third of the women undergoing elective caesarean delivery developed perioperative hypothermia with a core temperature <36.0°C. The mean duration of maternal hypothermia was 77 min, lasting well into the postoperative period for many patients. These data should remind healthcare professionals of the importance of measuring core temperature in all phases of the perioperative setting and to consider optimal warming measures to avoid and treat hypothermia.

Development and validation of a nomogram to predict hypothermia in adult burn patients during escharectomy under general anesthesia.

BACKGROUND: It is very common for burn patients to have hypothermia during escharectomy under general anesthesia, which increases the blood transfusion demand of burn patients, and may lead to blood coagulation disorder or even increase the mortality of patients. It is important to predict the occurrence of hypothermia in advance, but we lack a prognostic prediction model. Our study aimed to develop a nomogram to predict the incidence of hypothermia in adult burn patients undergoing escharectomy under general anesthesia to intervention the hazards associated with hypothermia early. METHODS: This retrospective study included 978 adult burn patients who underwent simple escharectomy under general anesthesia during hospitalization between January 2017 and December 2022, they were further divided into a training cohort and a validation cohort. The clinical data were recorded in electronic medical record system and a self-made collection table of intraoperative hypothermia. The preliminary predictive factors for hypothermia which undergoing simple escharectomy under general anesthesia in burn patients were determined using least absolute shrinkage and selection operator (LASSO) at first, then the final predictive factors determined using binary logistic regression analyses and a nomogram to predict the occurrence of hypothermia was established. The index of concordance(C-index), calibration curves, receiver operating characteristic (ROC) curve, and decision curve analysis (DCA) were used to evaluate the performance of the model. RESULTS: A total of 211 patients with hypothermia and 767 patients without hypothermia were selected. Least absolute shrinkage and selection operator regression analysis and binary logistic regression results concluded that burn index, urinary volume, blood transfusion volume and irrigation volume were significantly associated with hypothermia in burn patients undergoing escharectomy under general anesthesia. The nomogram based on these four variables had good predictive efficiency for hypothermia in adult burn patients during escharectomy under general anesthesia, the C-index in the training cohort was 0.903, areas under the receiver operating characteristic curves (AUROC) of for the training cohort (95 % CI 0.877-0.920) and 0.875 for the validation cohort (95 % CI 0.852-0.897) indicated satisfactory discriminative ability of the nomogram, and the calibration curves for the training cohort and the validation cohort also fit as well, indicating that the nomogram had good clinical application value. CONCLUSIONS: Hypothermia in burn patients during escharectomy under general anesthesia is associated with burn index, urinary volume, blood transfusion volume and irrigation volume. We successfully developed a practical nomogram to accurately predict hypothermia, which is a practical method helping clinicians rapidly and conveniently diagnose and guide the treatment of hypothermia in burn patients during escharectomy under general anesthesia.

Hypothermia on admission and its association with neonatal mortality and morbidity in neonatal intensive care unit.

BACKGROUND: Neonatal hypothermia is a drop in the newborn's core temperature less than 36.5°C. It is crucial in neonatal morbidity and mortality, particularly in preterm infants. This research aimed to assess the incidence and risk factors of neonatal hypothermia and its effect on neonatal mortality and short-term morbidity during Neonatal Intensive Care Unit (NICU) admission. METHODS: This observational study was conducted on all neonates admitted to the NICU at Benha University Hospital. The core temperature was measured on admission for all admitted neonates and were followed up to assess the impact of hypothermia on short-term outcomes and mortality. RESULTS: A total of 323 neonates were admitted to the NICU throughout the research period. Thirty-five cases were excluded due to congenital anomalies or missing or late admission temperature recordings. The study included 288 neonates whose mean gestational age was 34.6±3.4 weeks, and their mean birth weight was 2.35±0.9 kg. Two-thirds (66%) of the neonates had core temperatures indicating hypothermia (axillary temperature of less than 36.5°C), one-third (33%) were normothermic, and only three (1%) were hyperthermic. Neonates with hypothermia had statistically lower gestational age, higher frequency of multiple births, prolonged need for respiratory support, higher rates of pulmonary hemorrhage, sepsis, intraventricular hemorrhage (IVH), and necrotizing enterocolitis, longer hospital stay, and mortality. CONCLUSIONS: There is a high incidence of neonatal hypothermia at NICU admission. Lower gestational age, increased multiples, lower APGAR score, lower birth weight, and lack of antenatal steroids were significantly associated with hypothermia at NICU admission. Hypothermia was found to be a significant factor contributing to increased mortality and morbidity rates in affected neonates.

Inadvertent hypothermia in paediatric radiotherapy practices under sedation: a single centre observational study.

OBJECTIVE: To detect changes in body temperature during outpatient procedures and to identify factors associated with hypothermia in the paediatric population undergoing radiotherapy under sedation. METHODS: The observational study was conducted between July and October 2022 at Ankara City Hospital, Turkey, and comprised paediatric cancer patients aged from 1 month to 18 years who needed sedation or general anaesthesia during radiotherapy. Baseline body temperature T1 was measured before transportation to the radiotherapy room, while body temperature T2 was taken after radiotherapy. Data was analysed using SPSS 20. RESULTS: A total of 152 radiotherapy sessions related to 13 children were evaluated. There were 8(61%) boys and 5(38%) girls with overall mean 4.46±3.45 years (range: 2-13 years). The mean body surface area as 0.70±0.212. Radiotherapy was performed in 9(69%) patients, while 4(31%) patients underwent tomotheraphy. The dose used was 180cGy in 12(92.3%) patients. Hypothermia was observed in at least one session in 12(92.3%) patients. There was significant difference in body temperature at baseline and post-radiotherapy (p<0.05). CONCLUSIONS: There were significant changes in body temperature during outpatient procedures in the paediatric population undergoing radiotherapy under sedation.

Effect of Prewarming on Perioperative Hypothermia in Patients Undergoing Loco-Regional or General Anesthesia: A Randomized Clinical Trial.

Background and Objectives: Redistribution hypothermia occurs during anesthesia despite active intraoperative warming. Prewarming increases the heat absorption by peripheral tissue, reducing the central to peripheral heat gradient. Therefore, the addition of prewarming may offer a greater preservation of intraoperative normothermia as compared to intraoperative warming only. Materials and Methods: A single-center clinical trial of adults scheduled for non-cardiac surgery. Patients were randomized to receive or not a prewarming period (at least 10 min) with convective air devices. Intraoperative temperature management was identical in both groups and performed according to a local protocol. The primary endpoint was the incidence, the magnitude and the duration of hypothermia (according to surgical time) between anesthetic induction and arrival at the recovery room. Secondary outcomes were core temperature on arrival in operating room, surgical site infections, blood losses, transfusions, patient discomfort (i.e., shivering), reintervention and hospital stay. Results: In total, 197 patients were analyzed: 104 in the control group and 93 in the prewarming group. Core temperature during the intra-operative period was similar between groups (p = 0.45). Median prewarming lasted 27 (17-38) min. Regarding hypothermia, we found no differences in incidence (controls: 33.7%, prewarming: 39.8%; p = 0.37), duration (controls: 41.6% (17.8-78.1), prewarming: 45.2% (20.6-71.1); p = 0.83) and magnitude (controls: 0.19 °C · h-1 (0.09-0.54), prewarming: 0.20 °C · h-1 (0.05-0.70); p = 0.91). Preoperative thermal discomfort was more frequent in the prewarming group (15.1% vs. 0%; p < 0.01). The interruption of intraoperative warming was more common in the prewarming group (16.1% vs. 6.7%; p = 0.03), but no differences were seen in other secondary endpoints. Conclusions: A preoperative prewarming period does not reduce the incidence, duration and magnitude of intraoperative hypothermia. These results should be interpreted considering a strict protocol for perioperative temperature management and the low incidence of hypothermia in controls.

The effect of combining prewarming with intraoperative phenylephrine infusion on the prevention of hypothermia in patients undergoing urological surgery: a prospective, randomized, and controlled trial.

Background: Hypothermia is common in patients undergoing urological surgery; however, no single preventative modality is completely effective. This study evaluated the effects of combining prewarming with intraoperative phenylephrine infusion for the prevention of hypothermia in patients undergoing urological surgery. Methods: This prospective study enrolled 58 patients scheduled for urological surgery under general anesthesia. The patients were randomized into two groups (n = 29). Patients in the experimental (prewarming and phenylephrine infusion) group (PP group) received prewarming for 20 min and intraoperative phenylephrine infusion, whereas those in the control group (C group) received no active prewarming with only intermittent administration of vasoactive agents. The patient's sublingual temperatures before and after anesthesia and nasopharyngeal temperature during anesthesia were recorded as core temperatures. Results: The incidence of intraoperative hypothermia was higher in the C group than in the PP group (57.7% [15/26] vs. 23.1% [6/26], P = 0.01). The severity of intraoperative hypothermia was higher in the C group than in the PP group (P = 0.004). The nasopharyngeal temperature at the end of surgery was lower in the C group than in the PP group (35.8 ± 0.6°C vs. 36.3 ± 0.4°C, P = 0.002). The trend of core temperature decline during the first hour after anesthesia induction differed between the two groups (P = 0.003; its decline was more gradual in the PP group). Conclusions: The combination of prewarming for 20 min and intraoperative phenylephrine infusion reduced the incidence and severity of intraoperative hypothermia and modified the trend of decreasing core temperatures in patients undergoing urological surgery.

Risk factors for intraoperative hypothermia in infants during general anesthesia: A retrospective study.

This study aimed to determine the incidence and evaluate the risk factors and outcomes of intraoperative hypothermia (IH) during general anesthesia in infants. Retrospective analysis of prospectively collected data. A total of 754 infants younger than 1 year old who underwent surgery under general anesthesia were included. Intraoperative body temperature fluctuations, surgical and anesthetic data, postoperative complications, and infant outcomes were recorded. Logistic regression algorithms were used to evaluate potential risk factors. Among the 754 infants, 47.88% developed IH (<36 °C) and 15.4% of them experienced severe hypothermia (<35 °C). The average lowest temperature in hypothermia patients was 35.06 ± 0.69°C with a duration of 82.23 ± 50.59 minutes. Neonates tended to experience hypothermia (37.7% vs 7.6%, P < .001) and prematurity was more common in patients with IH (29.4% vs 16.8%, P < .001). Infants with hypothermia experienced a longer length of stay in the post anesthesia care units and intensive care units, postoperative hospitalizations, and tracheal extubation as well as a higher rate of postoperative hemorrhage than those with normothermia (all P < .05). Several factors were proved to be associated with an increased risk of IH after multivariate analysis: neonate (odds ratio [OR] = 3.685, 95% CI 1.839-7.382), weight (OR = 0.599, 95% CI 0.525-0.683), American society of anesthesiologists (OR = 3.418, 95% CI 2.259-5.170), fluid > 20 mL/kg (OR = 2.380, 95% CI 1.389-4.076), surgery time >60 minutes (OR = 1.785, 95% CI 1.030-3.093), and pre-warming (OR = 0.027, 95% CI 0.014-0.052). This retrospective study found that neonates, lower weight, longer surgery times, more fluid received, higher American society of anesthesiologists stage, and no pre-warming were all significant risk factors for IH during general anesthesia in infants.

Incidence of Neonatal Hypothermia in the Newborn Nursery and Associated Factors.

Importance: Thermoregulation is a key component of well-newborn care. There is limited epidemiologic data on hypothermia in late preterm and term infants admitted to the nursery. Expanding on these data is essential for advancing evidence-based care in a population that represents more than 3.5 million births per year in the US. Objective: To examine the incidence and factors associated with hypothermia in otherwise healthy infants admitted to the newborn nursery following delivery. Design, Setting, and Participants: A retrospective cohort study using electronic health record data from May 1, 2015, to August 31, 2021, was conducted at a newborn nursery at a university-affiliated children's hospital. Participants included 23 549 infants admitted to the newborn nursery, from which 321 060 axillary and rectal temperature values were analyzed. Exposures: Infant and maternal clinical and demographic factors. Main Outcomes and Measures: Neonatal hypothermia was defined according to the World Health Organization threshold of temperature less than 36.5 °C. Hypothermia was further classified by severity (mild: single episode, temperature 36.0-36.4 °C; moderate/severe: persistent or recurrent hypothermia and/or temperature <36.0 °C) and timing (early: all hypothermic episodes occurred within the first 24 hours after birth; late: any episode extended beyond the first 24 hours). Results: Of 23 549 included infants (male, 12 220 [51.9%]), 5.6% were late preterm (35-36 weeks' gestation) and 4.3% were low birth weight (≤2500 g). The incidence of mild hypothermia was 17.1% and the incidence of moderate/severe hypothermia was 4.6%. Late hypothermia occurred in 1.8% of infants. Lower birth weight and gestational age and Black and Asian maternal race and ethnicity had the highest adjusted odds across all classifications of hypothermia. The adjusted odds ratios of moderate/severe hypothermia were 5.97 (95% CI 4.45-8.00) in infants with a birth weight less than or equal to 2500 vs 3001 to 3500 g, 3.17 (95% CI 2.24-4.49) in 35 week' vs 39 weeks' gestation, and 2.65 (95% CI 1.78-3.96) in infants born to Black mothers and 1.94 (95% CI 1.61-2.34) in infants born to Asian mothers vs non-Hispanic White mothers. Conclusions and Relevance: In this cohort study of infants in the inpatient nursery, hypothermia was common, and the incidence varied by hypothermia definition applied. Infants of lower gestational age and birth weight and those born to Black and Asian mothers carried the highest odds of hypothermia. These findings suggest that identifying biological, structural, and social determinants of hypothermia is essential for advancing evidence-based equitable thermoregulatory care.

Associations Between Core Temperature Disorders and Outcomes of Pediatric Intensive Care Unit Patients.

BACKGROUND: The few studies of associations between fever and outcomes in pediatric intensive care unit (PICU) patients have conflicting findings. Associations between hypothermia and patient outcomes have not been studied. OBJECTIVE: To investigate the incidence and characteristics of fever and hypothermia and their associations with adverse outcomes among PICU patients. METHODS: Patients consecutively admitted to 2 PICUs in a 2-year period were prospectively studied. Core temperature was mainly measured by rectal or axillary thermometry. Fever and hypothermia were defined as core temperatures of greater than 38.0 °C and less than 36.0 °C, respectively. Prolonged mechanical ventilation, prolonged PICU stay, and PICU mortality were the adverse patient outcomes studied. Associations between patient outcomes and core temperature disorders were evaluated with univariate comparisons and multivariate analyses. RESULTS: Of 545 patients enrolled, fever occurred in 299 (54.9%) and hypothermia occurred in 161 (29.5%). Both temperature disorders were independently associated with prolonged mechanical ventilation and prolonged PICU stay (P < .001) but not with PICU mortality. Late onset of fever (P < .001) and hypothermia (P = .009) were independently associated with prolonged mechanical ventilation, fever magnitude and duration (both P < .001) were independently associated with prolonged PICU stay, and fever magnitude (P < .001) and infectious cause of hypothermia (P= .01) were independently associated with higher PICU mortality. CONCLUSIONS: These findings provide evidence that the manifestation and characteristics of fever and hypothermia are independent predictors of adverse outcomes in PICU patients.

Construction and validation of a risk prediction model for intraoperative hypothermia in elderly patients undergoing total hip arthroplasty.

AIMS: To construct and validate an intraoperative hypothermia risk prediction model for elderly patients undergoing total hip arthroplasty (THA). METHODS: We collected data from 718 patients undergoing THA in a tertiary hospital from January 2021 to December 2022. Of these patients, 512 were assigned to the modeling group from January 2021 to April 2022, and 206 participants were assigned to the validation group from May 2022 to December 2022. A logistic regression analysis was performed to construct the model. The area under the curve (AUC) was used to test the model's predictive ability. RESULTS: The incidence rate of intraoperative hypothermia was 51.67%. The risk factors entered into the risk prediction model were age, preoperative hemoglobin level, intraoperative blood loss, postoperative hemoglobin level, and postoperative systolic blood pressure. The model was constructed as follows: logit (P) = - 10.118 + 0.174 × age + 1.366 × 1 (preoperative hemoglobin level) + 0.555 × 1 (postoperative hemoglobin level) + 0.009 × 1 (intraoperative blood loss) + 0.066 × 1 (postoperative systolic blood pressure). Using the Hosmer-Lemeshow test, the P value was 0.676 (AUC, 0.867). The Youden index, sensitivity, and specificity were 0.602, 0.790, and 0.812, respectively. The incidence rates of intraoperative hypothermia in the modeling and validation groups were 53.15% and 48.06%, respectively. The correct practical application rate was 89.81%. This model had good application potential. CONCLUSIONS: This risk prediction model has good predictive value and can accurately predict the occurrence of intraoperative hypothermia in patients who undergo THA, which provides reliable guidance for clinical work and has good clinical application value.

Inadvertent Perioperative Hypothermia in Ambulatory Surgery Patients: Incidence, Risk Factors, and Prevention Initiatives.

PURPOSE: Although the number and complexity of ambulatory surgical interventions has grown considerably over the years, it has not been fully established whether hypothermia still poses a risk for these interventions. In this study, we aimed to determine the incidence, risk factors, and methods applied to prevent perioperative hypothermia in ambulatory surgery patients. DESIGN: A descriptive research design was used. METHODS: The study was conducted with 175 patients between May 2021 and March 2022 in the outpatient units of a training and research hospital in Mersin, Turkey. Data were collected using the Patient Information and Follow-up Form. FINDINGS: The incidence of perioperative hypothermia was 20% in ambulatory surgery patients. Hypothermia developed in 13.7% of the patients at the 0th minute at the PACU, and 96.6% of the patients were not warmed intraoperatively. We noted a statistically significant relationship between perioperative hypothermia and advanced age (≥60 years), high American Society of Anesthesiologists' (ASA) class, and low hematocrit values. In addition, we determined that the female gender, presence of chronic diseases, general anesthesia, and a long operation time were other risk factors for hypothermia in the perioperative period. CONCLUSIONS: The incidence of hypothermia during ambulatory surgeries is lower than that in inpatient surgeries. The warming rate of ambulatory surgery patients, which is quite low, can be improved by increasing the awareness of the perioperative team and following the guidelines.