Hypothermia after cesarean delivery and its reversal with lorazepam

The effect of forced-air warming in the cesarean section on maternal hypothermia, shivering, and thermal comfort: A randomized controlled trial

This trial was carried out to investigate the effect of forced air warming in various body areas of women on hypothermia during cesarean delivery. The patients in the study groups (n = 76) were assigned to the full-body warming group, upper-extremity warming group, lower-extremity warming group, and control groups. The intervention groups received forced-air warming 30 min before the surgery and continued until 30 min after surgery. The incidence of hypothermia was significantly higher in the control group than in the other groups at the 60th minute of the operation (p < 0.01). The intervention and control groups showed significant differences in the frequency of shivering at the entrance to the PACU (p = 0.001). Thermal comfort scores have significant difference between the control group and all of the intervention groups (p<.001). It is said that the full-body forced-air warming technique prevents hypothermia, shivering, and thermal discomfort in women Cesarean Section (CS).

Hypothermia With Paradoxical Symptoms: A Case Series of Cesarean Deliveries With Intrathecal Morphine

Women receiving intrathecal morphine for cesarean delivery may experience hypothermia with paradoxical symptoms of sweating, nausea, and shivering. Despite being relatively rare in comparison to commonly experienced symptoms of perioperative hypothermia, hypothermia with paradoxical symptoms affects early maternal recovery and comfort. The cause is undetermined, and treatment approaches vary. Regular active-warming strategies may not be tolerated because of the paradoxical symptoms of sweating and feeling overheated. This case series aims to explore the phenomenon through the evaluation of health care records of women receiving intrathecal morphine for cesarean delivery at a single, tertiary health care institution in Australia from 2015 to 2018. We also summarize published literature to review treatment approaches used in the care of women experiencing profound heat loss while feeling overheated.

Midazolam for the Successful Treatment of Refractory Spinal-Anesthesia-Associated Hypothermia After Cesarean Delivery

Cesarean deliveries receiving spinal anesthesia with intrathecal morphine are associated with post-operative hypothermia. Lorazepam has been proposed as a reversal agent for treating intrathecal morphine-associated post-cesarean hypothermia. Midazolam is a benzodiazepine familiar to most anesthesia providers and is frequently administered in the perioperative period. We present a post-cesarean delivery spinal anesthesia-associated hypothermia patient successfully treated with intravenous midazolam.

Development and validation of a risk prediction scale for hypothermia during cesarean section: A prospective study

Background

Evidence shows that active insulation can reduce the incidence of hypothermia during cesarean section; however, compliance is lower than recommended. Moreover, several aspects of temperature management via active heat preservation remain unclear, including patient indications, timing, methods, and duration. Therefore, promptly identifying parturients at a high risk for hypothermia during cesarean section is crucial.

Objective

To develop and validate a scale for predicting hypothermia in parturients during cesarean section.

Design

Prospective study.

Setting

Three grade A hospitals in Hunan Province, China.

Participants

The prediction scale was developed based on data from 369 parturients who underwent cesarean section from July 2018 to January 2019. Inclusion criteria were as follows: cesarean section under lumbar anesthesia, epidural anesthesia, or combined lumbar and epidural anesthesia; voluntary participation in the study and completion of the informed consent form; age >18 years.

Methods

Univariate and multivariate analyses were used to determine factors influencing hypothermia and establish the predictive model for hypothermia risk during cesarean section. The Hosmer-Lemeshow test was used to determine the goodness of fit of the prediction tool, and the area under the receiver operating characteristic curve was used to determine the predictive ability of the proposed scale. The cutoff value of the prediction scale was determined according to the Youden index.

Results

In the logistic regression prediction model, the Hosmer-Lemeshow goodness-of-fit test yielded a p-value of 0.425. The area under the receiver operating characteristic curve was 0.888. The model exhibited a good fitting effect and discriminant validity. Total risk scores for hypothermia ranged from 0 to 11. A score of 7 was used as the diagnostic cutoff value. Parturients during the operation who had total scores of ≥7 and <7 were considered the high-risk and low-risk groups, respectively. The area under the receiver operating characteristic curve for the scale was 0.891. The authenticity evaluation indicated that the incidence of hypothermia was significantly higher in the high-risk group than in the low-risk group.

Conclusions

The risk prediction scale developed in this study exhibits moderately predictive efficiency, sensitivity, and specificity for identifying parturients at high risk of hypothermia during cesarean section. Implementing this scale in clinical practice may help to decrease the incidence of hypothermia in such patients.

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abstract

This new predictive model can identify women who are at a high risk of hypothermia during cesarean section.

Forced-air warming and continuous core temperature monitoring with zero-heat-flux thermometry during cesarean section: a retrospective observational cohort study

Background

Over 30% of parturients undergoing spinal anesthesia for cesarean section become intraoperatively hypothermic. This study assessed the magnitude of hypothermic insult in parturients and newborns using continuous, high-resolution thermometry and evaluated the efficiency of intraoperative forced-air warming for prevention of hypothermia.

Methods

One hundred and eleven parturients admitted for elective or emergency cesarean section under spinal anesthesia with newborn bonding over a 5-month period were included in this retrospective observational cohort study. Patients were divided into two groups: the passive insulation group, who received no active warming, and the active warming group, who received convective warming through an underbody blanket. Core body temperature was continuously monitored by zero-heat-flux thermometry and automatically recorded by data-loggers. The primary outcome was the incidence of hypothermia in the operating and recovery room. Neonatal outcomes were also analyzed.

Results

The patients in the passive insulation group had significantly lower temperatures in the operating room compared to the actively warmed group (36.4°C vs. 36.6°C, p = 0.005), including temperature at skin closure (36.5°C vs. 36.7°C, p = 0.017). The temperature of the newborns after discharge from the postanesthetic care unit was lower in the passive insulation group (36.7°C vs. 37.0°C, p = 0.002); thirteen (15%) of the newborns were hypothermic, compared to three (4%) in the active warming group (p < 0.01).

Conclusion

Forced-air warming decreases perioperative hypothermia in parturients undergoing cesarean section but does not entirely prevent hypothermia in newborns while bonding. Therefore, it can be effectively used for cesarean section, but special attention should be given to neonates.

Neuraxial Morphine-Induced Hypothermia After Cesarean Delivery Managed With Nalbuphine: A Case Report

Neuraxial morphine-induced hypothermia has been reported as a relatively rare complication, with the successful use of naloxone and lorazepam to reverse symptoms. We report a case of intrathecal morphine-induced hypothermia with profuse sweating, intractable nausea, and vomiting in a primigravid woman undergoing cesarean delivery in the setting of preeclampsia. All symptoms rapidly resolved after a single dose of intravenous nalbuphine. Because nalbuphine has a long track record of safe use on labor and delivery units, it is an attractive and novel choice for treatment of neuraxial morphine-induced hypothermia.

Altered Thermoregulatory Responses Following Spinal Morphine for Caesarean Delivery: a Case Report

OBJECTIVE

Spinal anaesthesia interferes with physiological thermoregulatory responses, potentially leading to peri-operative hypothermia. Spinal morphine can further compound this by a paradoxical clinical presentation leading to poor patient outcome.

CASE REPORT

Following an uneventful caesarean delivery (CD) under spinal anaesthesia with intrathecal morphine for post-operative analgesia, a parturient presented in the recovery room with increasing somnolence, excessive sweating and a sensation of feeling hot. She was haemodynamically stable, but her temperature was 34.5°C. Active warming measures were implemented, and normothermia was achieved in 3 hours.

CONCLUSION

Spinal morphine can alter the clinical presentation of hypothermia by manifesting as excessive sweating and subjective sensation of warmth. Teams involved in the perioperative care of parturients should be aware of (a) the possibility of spinal anaesthesia causing perioperative hypothermia, (b) intrathecal morphine masking the clinical presentation of hypothermia and (c) the importance of monitoring temperature of patients who have received spinal anaesthesia with added morphine.

Persistent Hypothermia and Excessive Sweating Following Intrathecal Morphine Administration in a Teenage Boy: A Case Report

Introduction

Opioids are used intrathecally to manage surgical pain. There are few reports of hypothermia after spinal morphine injection, none in the pediatric population. We present a teenager's case of mild hypothermia.

Case Presentation

A 15-year-old boy was scheduled for elective abdominal laparotomy. General anesthesia was combined with spinal anesthesia, using levobupivacaine and morphine. In the recovery room, he presented a decreased tympanic temperature (34.4°C) associated with excessive sweating, hyperglycemia, and complained of feeling hot. All other vital signs were normal. It was decided to maintain clinical vigilance and hourly monitoring of temperature and glycaemia values. Despite active warming, he remained hypothermic for 16 hours, with gradual remission of symptoms and normalization of glycemic values. It is unknown how intrathecal morphine causes hypothermia. The most viable hypothesis is its effect on the hypothalamus. In our case the most probable causes of post anesthesia hypothermia were excluded; therefore, we can admit that the cause of hypothermia was the spinal administration of morphine. Some reports used naloxone and lorazepam successfully. In our report, they disappeared spontaneously 16 hours later, which corroborates our diagnosis.

Conclusions

Children undergoing subarachnoid block with with intrathecal morphine may develop a disruption on thermoregulation, leading to a resistant postoperative hypothermia associated with excessive sweating.

Intrathecal Morphine-Related Perioperative Hypothermia in Women Undergoing Cesarean Delivery: A Retrospective Case-Control Study

PURPOSE

Rates of inadvertent perioperative hypothermia among women undergoing spinal anesthesia for cesarean delivery are reported to be high. Intrathecal morphine has been noted to have a potentially potent effect on thermoregulation. This retrospective case-control study sought to investigate the incidence of perioperative hypothermia in women undergoing cesarean delivery with and without intrathecal morphine and to describe any clinical factors associated with the condition, the identification of which would provide direction for nursing priorities in the care of the condition.

DESIGN

A retrospective case-controlled study design was used.

METHODS

The charts of 358 women who had undergone emergency or elective cesarean delivery under spinal anesthesia were reviewed: 179 having received intrathecal morphine and 179 having received spinal anesthesia without intrathecal morphine (control group). SPSS (IBM, Armonk, New York), version 22, was used for data analysis, including logistic regression to predict the outcome of hypothermia across the study population.

FINDINGS

There was no significant difference (P = .62; 95% confidence interval, -0.09 to 0.15) in mean postoperative temperature for the morphine group (mean postanesthesia care unit arrival temperature, 35.91°C; standard deviation, 0.59) and the no morphine group (mean postanesthesia care unit arrival temperature, 35.88°C; standard deviation, 0.52). However, within groups, the temperature decline preoperatively to postoperatively was statistically (and clinically) significant.

CONCLUSIONS

The results refute the suggestion that intrathecal morphine contributes to greater core temperature decline in this population; however, it does confirm that perioperative hypothermia is a prevalent concern for women undergoing cesarean delivery and that pre-emptive measures should be routinely considered by health care providers.

Preoperative Warming Versus no Preoperative Warming for Maintenance of Normothermia in Women Receiving Intrathecal Morphine for Cesarean Delivery: A Single-Blinded, Randomized Controlled Trial

BACKGROUND

Rates of hypothermia for women undergoing spinal anesthesia for cesarean delivery are high and prevention is desirable. This trial compared the effectiveness of preoperative warming versus usual care among women receiving intrathecal morphine, which is thought to exacerbate perioperative heat loss.

METHODS

A prospective, single-blinded, randomized controlled trial compared 20 minutes of forced air warming (plus intravenous fluid warming) versus no active preoperative warming (plus intravenous fluid warming) in 50 healthy American Society of Anesthesiologists graded II women receiving intrathecal morphine as part of spinal anesthesia for elective cesarean delivery. The primary outcome of maternal temperature change was assessed via aural canal and bladder temperature measurements at regular intervals. Secondary outcomes included maternal thermal comfort, shivering, mean arterial pressure, agreement between aural temperature, and neonatal outcomes (axillary temperature at birth, Apgar scores, breastfeeding, and skin-to-skin contact). The intention-to-treat population was analyzed with descriptive statistics, general linear model analysis, linear mixed-model analysis, χ test of independence, Mann-Whitney, and Bland-Altman analysis. Full ethical approval was obtained, and the study was registered on the Australia and New Zealand Clinical Trials Registry (Trial No: 367160, registered at http://www.ANZCTR.org.au/).

RESULTS

Intention-to-treat analysis (n = 50) revealed no significant difference in aural temperature change from baseline to the end of the procedure between groups: F (1, 47) = 1.2, P = .28. There were no other statistically significant differences between groups in any of the secondary outcomes.

CONCLUSIONS

A short period of preoperative warming is not effective in preventing intraoperative temperature decline for women receiving intrathecal morphine. A combination of preoperative and intraoperative warming modalities may be required for this population.

Effect of Intraoperative Phenylephrine Infusion on Redistribution Hypothermia During Cesarean Delivery Under Spinal Anesthesia

An observational clinical study to evaluate the effect of phenylephrine infusion on maternal temperatures during scheduled cesarean delivery under spinal anaesthesia was conducted in 40 ASA physical status II parturients. Following placement of spinal anesthesia, phenylephrine infusion was initiated at 40 μg/min and titrated to maintain mean arterial pressure within 20 percent of baseline. Maternal oral temperature, heart rate, and blood pressure were measured at baseline, spinal placement, every 10 minutes thereafter for 60 minutes. Phenylephrine dose received was documented every ten minutes. The range in maternal temperature change was 0.06-0.29°C. The lowest recorded temperature was 36.3°C. Decreased maternal temperature was associated with duration of anesthesia and cumulative phenylephrine dose in a univariate model (P<0.001 for all). The multivariable model showed an association between a greater decrease in maternal temperature with larger doses of phenylephrine being administered.

A systematic review of the effectiveness of warming interventions for women undergoing cesarean section

BACKGROUND

Women undergoing cesarean section are vulnerable to adverse effects associated with inadvertent perioperative hypothermia, but there has been a lack of synthesized evidence for temperature management in this population. This systematic review aimed to synthesize the best available evidence in relation to preventing hypothermia in mothers undergoing cesarean section surgery.

METHODS

Randomized controlled trials meeting the inclusion criteria (adult patients of any ethnic background, with or without comorbidities, undergoing any mode of anesthesia for any type of cesarean section) were eligible for consideration. Active or passive warming interventions versus usual care or placebo, aiming to limit or manage core heat loss in women undergoing cesarean section were considered. The primary outcome was maternal core temperature. A comprehensive search with no language restrictions was undertaken of multiple databases from their inception until May 2012. Two independent reviewers using the standardized critical appraisal instrument for randomized controlled trials from the Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instruments (JBI-MASTARI) assessed retrieved papers for methodological quality and conducted data collection. Where possible, results were combined in a fixed effects meta-analysis using the Cochrane Collaboration Review Manager software. Due to heterogeneity for one outcome, random effects meta-analysis was also used.

RESULTS

A combined total of 719 participants from 12 studies were included. Intravenous fluid warming was found to be effective at maintaining maternal temperature and preventing shivering. Warming devices, including forced air warming and under-body carbon polymer mattresses, were effective at preventing hypothermia. However, effectiveness increased if the devices were applied preoperatively. Preoperative warming devices reduced shivering and improved neonatal temperatures at birth. Intravenous fluid warming did not improve neonatal temperature, and the effectiveness of warming interventions on umbilical pH remains unclear.

LINKING EVIDENCE TO ACTION

Intravenous fluid warming by any method improves maternal temperature and reduces shivering during and after cesarean section, as does preoperative body warming. Preoperative warming strategies should be utilized where possible. Preoperative or intraoperative warmed IV fluids should be standard practice. Warming strategies are less effective when intrathecal opioids are administered. Further research is needed to investigate interventions in emergency cesarean section surgery. Larger scale studies using standardized, clinically meaningful temperature measurement time points are required.

Influence of hydatidiform mole follow-up setting on postmolar gestational trophoblastic neoplasia outcomes: a cohort study

OBJECTIVE

To assess the influence of hydatidiform mole (HM) management setting (reference center versus other institutions) on gestational trophoblastic neoplasia (GTN) outcomes.

METHODS

This cohort study included 270 HM patients attending Botucatu Trophoblastic Diseases Center (BTDC, São Paulo State University, Brazil) between January 1990 and December 2009 (204 undergoing evacuation and entire postmolar follow-up at BTDC and 66 from other institutions [OIs]). GTN characteristics and outcomes were analyzed and compared according to HM management setting. The confounding variables assessed included age, gravidity, parity, number of abortions and HM type (complete or partial). Postmolar GTN outcomes were compared using Mann-Whitney's test, chi2 test or Fisher's exact test.

RESULTS

Postmolar GTN occurred in 34 (34/204 = 16.7%) BTDC patients and in 27 (27/66 = 40.9%) of those initially treated in other institutions. BTDC patients showed lower metastasis rate (5.8% vs. 48%, p = 0.003) and lower median FIGO (2002) score (2.00 [1.00, 3.00] vs. 4.00 [2.00, 7.00], p = 0.003]. Multiagent chemotherapy to treat postmolar GTN was required in 2 BTDC cases (5.9%) and in 8 OI cases (29.6%) (p = 0.017). Median time interval between molar evacuation and chemotherapy onset was shorter among BTDC patients (7.0 [6.0, 10.0] vs. 10.0 [7.0, 16.0], p = 0.040).

CONCLUSION

BTDC patients showed GTN characteristics indicative of better prognosis. This underscores the importance of GTD specialist centers.

Persistent hypothermia after intrathecal morphine: case report and literature review

PURPOSE

To describe a case of persistent hypothermia following spinal anesthesia with intrathecal morphine.

CLINICAL FEATURES

Following elective right total knee arthroplasty under spinal anesthesia with isobaric 0.5% bupivacaine 11 mg, fentanyl 15 μg, and preservative-free morphine 150 μg, a 57-yr-old female (93.5 kg, 151 cm) developed postoperative hypothermia with a nadir rectal temperature of 33.6°C four hours after surgery. At times, her temperature could not be measured by tympanic, temporal arterial, oral, axillary, or rectal routes. In spite of the low temperature, the patient complained of feeling hot and was diaphoretic without shivering. With the exception of her temperature, her vital signs were normal postoperatively, and aside from hyperglycemia, complete blood count, electrolytes, thyroid-stimulating hormone, serum cortisol, troponin, and twelve-lead electrocardiogram were normal. Her temperature did not respond to warming efforts with a forced-air warming blanket, infusion of warmed intravenous crystalloid, and hourly bladder irrigation with warm saline through an indwelling urinary catheter. Normothermia returned after she received a small dose of sublingual lorazepam eight hours after surgery. The remainder of her postoperative stay was uneventful.

CONCLUSION

Patients undergoing spinal anesthesia with intrathecal morphine may develop postoperative hypothermia that is resistant to warming measures. This complication may be treated successfully with lorazepam.

Endogenous opiates and behavior: 2005

This paper is the 28th consecutive installment of the annual review of research concerning the endogenous opioid system, now spanning over a quarter-century of research. It summarizes papers published during 2005 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (Section 2), and the roles of these opioid peptides and receptors in pain and analgesia (Section 3); stress and social status (Section 4); tolerance and dependence (Section 5); learning and memory (Section 6); eating and drinking (Section 7); alcohol and drugs of abuse (Section 8); sexual activity and hormones, pregnancy, development and endocrinology (Section 9); mental illness and mood (Section 10); seizures and neurologic disorders (Section 11); electrical-related activity, neurophysiology and transmitter release (Section 12); general activity and locomotion (Section 13); gastrointestinal, renal and hepatic functions (Section 14); cardiovascular responses (Section 15); respiration and thermoregulation (Section 16); immunological responses (Section 17).