The incidence and prevention of hypothermia in newborn bonding after cesarean delivery: a randomized controlled trial

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).

Combined Forced Air Warming and Warm Intravenous Fluid Strategy for Perioperative Hypothermia in Cesarean Delivery: A Systematic Review and Meta-Analysis

PURPOSE

Evaluate the effect of a combined forced-air warming (FAW) and warm intravenous fluid (IVF) modality on maternal and neonatal outcomes in cesarean delivery under neuraxial anesthesia.

DESIGN

Systematic Review and Meta-analysis.

METHODS

An extensive search was conducted using PubMed, Cochrane Library, MEDLINE, CINAHL, Google Scholar, and other grey literature. Only randomized controlled trials examining the combined modality on maternal temperatures were included. Risk ratio (RR), mean difference (MD), and standardized mean difference (SMD) were used to estimate outcomes with suitable effect models. Quality of evidence was assessed using the Risk of Bias and GRADE system.

FINDINGS

Nine trials involving 595 patients were included. Combined strategy showed a smaller change in maternal temperature from baseline by 0.42°C (MD, -0.42; 95% CI, -0.62 to -0.22; P < .0001), higher temperature on PACU arrival (MD, 0.46; 95% CI, 0.11-0.82; P = .01), 15 minutes (MD, 0.43; 95% CI, 0.19-0.67; P = .0004) and 30 minutes after surgery (MD, 0.38; 95% CI, 0.12-0.64; P = .005). Combined strategy also reduced the incidence of hypothermia (RR, 0.55; 95% CI, 0.31-0.95; P = .03), and shivering (RR, 0.40; 95% CI, 0.28-0.58; P < .00001) with improvement in maternal comfort score (SMD; 0.38; 95% CI, 0.08-0.69; P = .01). However, there were no differences in clinical indicators of adverse neonatal outcomes. Lack of participants blinding, and substantial heterogeneity were limitations of this review.

CONCLUSION

The use of combined FAW and warm IVF is an effective strategy in mitigating perioperative hypothermia in cesarean delivery under neuraxial anesthesia.

[The cesarean procedure: Guidelines for clinical practice from the French College of Obstetricians and Gynecologists]

OBJECTIVE

To identify procedures to reduce maternal morbidity during cesarean.

MATERIAL AND METHODS

The quality of evidence of the literature was assessed following the GRADE® method with questions formulated in the PICO format (Patients, Intervention, Comparison, Outcome) and outcomes defined a priori and classified according to their importance. An extensive bibliographic search was performed on PubMed, Cochrane and EMBASE databases. The quality of the evidence was assessed (high, moderate, low, very low) and a (i) strong or (ii) weak recommendations or (iii) no recommendation were formulated. The recommendations were reviewed in two rounds with external reviewers (Delphi survey) to select the consensus recommendations.

RESULTS

Of the 27 questions, there was agreement between the working group and the external reviewers on 26. The level of evidence of the literature was insufficient to provide a recommendation on 15 questions. Preventing hypothermia is recommended to increase maternal satisfaction and comfort (weak recommendation) and to reduce neonatal hypothermia (strong recommendation). The quality of the evidence of the literature did not allow to recommend the skin disinfectant to be used nor the relevance of a preoperative vaginal disinfection nor the choice between the use or nonuse of an indwelling bladder catheterization (if micturition takes place 1 hour before the cesarean section). The Misgav-Ladach technique or its analogues should be considered rather than the Pfannenstiel technique to reduce maternal morbidity (weak recommendation) bladder flap before uterine incision should not be performed routinely (weak recommendation), but a blunt (weak recommendation) and cephalad-caudad extension of uterine incision (weak recommendation) should be considered to reduce maternal morbidity. Antibiotic prophylaxis is recommended to reduce maternal infectious morbidity (strong recommendation) without recommendation on its type or the timing of administration (before incision or after cord clamping). The administration of carbetocin after cord clamping does not significantly decrease the incidence of blood loss>1000 ml, anemia, or blood transfusion compared with the administration of oxytocin. Thus, it is not recommended to use carbetocin rather than oxytocin in cesarean. It is recommended that systematic manual removal of the placenta not to be performed (weak recommendation). An antiemetic should be administered after cord clamping in women having a planned cesarean under locoregional anaesthesia to reduce intraoperative and postoperative nausea and vomiting (strong recommendation) with no recommendation regarding choice of use one or two antiemetics. The level of evidence of the literature was insufficient to provide any recommendation concerning single or double-layer closure of the uterine incision, or the uterine exteriorization. Closing the peritoneum (visceral or parietal) should not be considered (weak recommendation). The quality of the evidence of the literature was not sufficient to provide recommendation on systematic subcutaneous closure, including in obese or overweight patients, or the use of subcuticular suture in obese or overweight patients. The use of subcuticular suture in comparison with skin closure by staples was not considered as a recommendation due to the absence of a consensus in the external review rounds.

CONCLUSION

In case of cesarean, preventing hypothermia, administering antiemetic and antibiotic prophylaxis after cord clamping are the only strong recommendations. The Misgav-Ladach technique, the way of performing uterine incision (no systematic bladder flap, blunt cephalad-caudad extension), not performing routine manual removal of the placenta nor closure of the peritoneum are weak recommendations and may reduce maternal morbidity.

Admission temperature and neonatal outcomes - single-centre experience in Saudi Arabia

Objective

This study aimed to investigate the association between admission hypothermia (AH), neonatal mortality and major neonatal morbidities in preterm infants <33 weeks' gestation. An additional aim of the study was to examine changes in the prevalence of admission hypothermia after the initiation of a thermoregulation quality improvement (QI) project.

Method

This is a retrospective cohort study of preterm infants < 33 weeks' gestation born at King AbdulAziz Medical City Riyadh (KAMC-R) between January 2017 to December 2020.

Results

Eight-hundred infants were born during the study period. Four hundred and one infants (50.1%) had an admission temperature of <36.5 °C and a further 399 (49.9%) had an admission temperature of >36.5 °C. The mortality before discharge was 15.7% in infants with AH compared to 4.8% among those with an admission temperature above 36.5 °C. This remained statistically significant after adjustments for gestational age and maternal PET status on a multivariate analysis (P = .001, OR 2.7,95%CI 1.5-4.7). The need for mechanical ventilation (P = .005) and incidence of surgical NEC (P = .030) were significantly different between the two temperature groups. Mean (SD) admission temperature increased from 36.3 °C to 36.6 °C following the thermoregulation intervention program (P <.001). Admission temperature <36 °C is associated with higher mortality in the first week (P = .001, OR 3.3,95% CI (1.7-6.6)) and increased incidence of cystic PVL (P = .04, OR 2.1, CI (1.03-4.3)).

Conclusion

Preterm infants with AH suffered higher mortality and greater neonatal morbidities.

Effect of active and passive warming on preventing hypothermia and shivering during cesarean delivery: a systematic review and meta-analysis of randomized controlled trials

Background

Perioperative hypothermia and shivering commonly occur in pregnant women undergoing cesarean section. The warming method is usually used to prevent hypothermia and shivering. However, the effect of active warming (AW) prior to passive warming (PW) on the perioperative outcomes of pregnant women and their offspring remains controversial.

Methods

This study aimed to investigate the effects of AW and PW on maternal and newborn perioperative outcomes during cesarean delivery. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, PubMed, Embase, Scopus, and the Cochrane Library were used to search for randomized controlled trials (RCTs) up to August 7, 2022. The Cochrane risk of bias assessment tool was used to assess articles selected for the systematic review. Continuous data were analyzed using weighted mean differences (WMDs) with 95% confidence intervals (CIs), and categorical data were analyzed by the random-effects model.

Results

A total of 1241 participants from twelve RCTs were selected for the final meta-analysis. AW was associated with a lower risk of maternal hypothermia (RR: 0.77, 95% CI: 0.63–0.93, P = 0.007) and shivering (RR: 0.56, 95% CI: 0.37–0.85; P = 0.007). AW was associated with high maternal temperature (WMD: 0.27, 95%CI: 0.14 to 0.40, P < 0.001). No significant difference was observed between AW and PW in terms of hypothermia (RR: 0.60, 95% CI: 0.24–1.51, P = 0.278), temperature (WMD: 0.31, 95% CI: − 0.00 to 0.62; P = 0.050), and umbilical vein PH in newborns (WMD: -0.00; 95% CI: − 0.02 to 0.02, P = 0.710).

Conclusions

These findings suggested that AW can better prevent maternal hypothermia and shivering than PW. In contrast, no significant effect was observed in newborns. Overall, the quality of the included studies is high due to RCTs, low risk of bias, consistency, and precision. We identified the quality of the overall evidence from the survey to be GRADE I.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05054-7.

Impact of "natural" cesarean delivery on peripartum blood loss: a randomized controlled trial

BACKGROUND

Early skin-to-skin contact after vaginal delivery increases milk production and may increase oxytocin release, leading to a reduction in the rate of postpartum hemorrhage.

OBJECTIVE

This study aimed to examine the effect of "natural" cesarean deliveries on perioperative maternal blood loss.

STUDY DESIGN

This was a randomized controlled trial conducted at a single university-affiliated medical center, between August 2016 and February 2018. Term singleton pregnancies scheduled for a planned cesarean delivery under spinal anesthesia were included. Women were randomized at a ratio of 1:1 to natural cesarean delivery (study group) or traditional cesarean delivery (control group) during the routine preoperative assessment. Women in the study group watched fetal extraction, had early skin-to-skin contact, and breastfed until the end of surgery. Neonates in the control group were presented to the mother for a few minutes. Blood samples were drawn from all women, during fascia closure, to determine oxytocin levels using an enzyme-linked immunosorbent assay kit. The laboratory component was performed after recruitment completion and was accomplished in February 2019. The primary outcome was postpartum hemoglobin levels. To detect a difference of 0.5 g/dL between the groups with α=0.05 and β=80%, 214 women were needed.

RESULTS

Of 214 randomized women, 23 were excluded. There was no difference in demographic and obstetrical variables between the groups. Postpartum hemoglobin levels were 10.1±1.1 and 10.3±1.3 g/dL in the study and control groups, respectively (P=.19). There was no difference in the rates of postpartum hemorrhage and blood transfusion. Maternal pain scores, satisfaction, and exclusive breastfeeding were comparable. Maternal oxytocin blood levels were 389.5±183.7 and 408.5±233.6 pg/mL in the study and control groups, respectively (P=.96). The incidence of neonatal hypothermia was comparable between the groups (P=.13).

CONCLUSION

Natural cesarean delivery did not affect perioperative hemoglobin level or maternal oxytocin blood concentration.

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.

Early essential newborn care is associated with improved newborn outcomes following caesarean section births in a tertiary hospital in Da Nang, Vietnam: a pre/post-intervention study

Background

To improve maternal and neonatal outcomes, Vietnam implemented early essential newborn care (EENC) using clinical coaching and quality improvement self-assessments in hospitals to introduce policy, practice and environmental changes. Da Nang Hospital for Women and Children began EENC with caesarean section births to inform development of national guidelines. This study compared newborn outcomes after caesarean sections pre/post-EENC introduction.

Methods

Maternity records of all live in-born hospital caesarean births and separate case records of the subpopulation admitted to the neonatal intensive care unit (NICU) were reviewed pre-EENC (November 2013–October 2014) and post-EENC (November 2014–October 2015) implementation. NICU admissions and adverse outcomes on NICU admission were compared using descriptive statistics.

Findings

A total of 16 927 newborns were delivered by caesarean section: 7928 (46.8%) pre-EENC and 8999 post-EENC (53.2%). Total NICU admissions decreased from 16.7% to 11.8% (relative risk 0.71; 95% CI 0.66 to 0.76) after introduction of EENC. Compared with the pre-EENC period, babies with hypothermia on admission to the NICU declined from 5.0% to 3.7% (relative risk 0.73; 95% CI 0.63 to 0.84) and cases of sepsis from 3.2% to 0.8% (relative risk 0.26; 95% CI 0.20 to 0.33) post-EENC implementation. While more than half of all newborns in the NICU were fed something other than breastmilk pre-EENC introduction, 85.8% were exclusively breast fed post-EENC (relative risk 1.86; 95% CI 1.75 to 1.98). Preterm newborns <2000 g receiving kangaroo mother care (KMC) increased from 50% to 67% (relative risk 1.33; 95% CI 1.12 to 1.59).

Conclusion

The EENC quality improvement approach with caesarean section births was associated with reduced NICU admissions, admissions with hypothermia and sepsis, and increased rates of exclusive breast feeding and KMC in the NICU.

The effect of combination of warm intravenous fluid infusion and forced air warming versus forced air warming alone on maternal temperature and shivering during cesarian delivery under spinal anesthesia

Objective

Administration of warm intravenous (IV) fluid infusion and use of forced air warmers is the most easy and physiologically viable method for maintaining normothermia during surgery and postsurgical periods This study was conducted to assess the effect of combination of active warming (AW) methods namely warm IV fluid infusion and forced air warming versus forced air warming only (WA) on maternal temperature during elective C-delivery under spinal anesthesia.

Materials and Methods

A total of 100 patients scheduled for elective c-section were grouped into those who received both warmed IV fluid infusion and forced air warmer (Combination of active warming WI= 50) and those who received only forced air warmer (WA = 50). Core body temperature and shivering incidence were recorded using a tympanic thermometer from prespinal till the end of surgery every 10 min and in postanesthesia care unit (PACU) at 0, 15, and 30 min.

Results

Core temperature showed statistically significant difference in 15, 35, 45, and 55 min between air warmer and warm infusion groups and in PACU at 0, 15, and 30 min, it was statistically significant (P = 0.000) among WI group (mean temperature = 36.79°C) when compared to WA group (mean temperature = 35.96°C). There was a lower incidence of shivering in WI compared to WA group, which is statistically significant.

Conclusion

Combination of warm Intravenous fluid infusion and Forced air warming is better than forced air warming alone. In maintaining near normal maternal core body temperature during elective cesarean section following spinal anesthesia. Combined warming method also reduces shivering incidence.

Effect of temperature maintenance by forced-air warming blankets of different temperatures on changes in inflammatory factors in children undergoing congenital hip dislocation surgery

Background

Hypothermia is associated with many adverse clinical outcomes in pediatric patients, and thus, it is important to find an effective and safe method for preventing peri-operative hypothermia and its associated adverse outcomes in pediatric patients. This study aimed to investigate the effect of forced-air warming blankets with different temperatures on changes in the transforming growth factor-β (TGF-β), tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-10 levels in children undergoing surgical treatment for developmental displacement of the hip (DDH).

Methods

The study included 123 children undergoing surgery for DDH under general anesthesia. The patients were randomly assigned to three groups, using a random number table: the 32, 38, and 43°C groups according to the temperature setting of the forced-air warming blankets. For each patient, body temperature was recorded immediately after anesthesia induction and intubation (T₀), at initial incision (T₁), at 1 h after incision (T₂), at 2 h after incision (T₃), at the end of surgery (T₄), immediately upon return to the ward after surgery (T₅), and then at 12 h (T₆), 24 h (T₇), 36 h (T₈), and 48 h (T₉) after the surgery. The serum levels of TGF-β, TNF-α, IL-1β, and IL-10 were measured at T₀ and T₄ for all groups.

Results

The number of patients with fever in the 38°C group was significantly less than those in the 32 and 43°C groups (χ² = 6.630, P = 0.036). At T₀, the body temperatures in the 38 and 43°C groups were significantly higher than that in the 32°C group (F = 17.992, P < 0.001). At T₂, the body temperature was significantly higher in the 43°C group than those in the 32 and 38°C groups (F = 12.776, P < 0.001). Moreover, at T₄, the serum levels of TGF-β (F = 3286.548, P < 0.001) and IL-10 (F = 4628.983, P < 0.001) were significantly increased in the 38°C group, and the serum levels of TNF-α (F = 911.415, P < 0.001) and IL-1β (F = 322.191, P < 0.001) were significantly decreased in the 38°C group, compared with the levels in the 32 and 43°C groups.

Conclusion

Force-air warming blankets set at 38°C maintained stable body temperature with less adverse outcome and effectively inhibited the inflammatory response in pediatric patients undergoing surgery for DDH.

Clinical trial registration

ChiCTR1800014820; http://www.chictr.org.cn/showproj.aspx?proj=25240.

Improving intraoperative temperature management in elective repeat cesarean deliveries: a retrospective observational cohort study

Background

Inadvertent perioperative hypothermia (< 36 °C) occurs frequently during elective cesarean delivery and most institutions do employ perioperative active warming. The purpose of this retrospective observational cohort study was to determine if the addition of preoperative forced air warming in conjunction with intraoperative underbody forced air warming improved core temperature and reducing inadvertent perioperative hypothermia during elective repeat elective cesarean delivery with neuraxial anesthesia.

Methods

We evaluated the addition of perioperative active warming to standard passive warming methods (preheated intravenous/irrigation fluids and cotton blankets) in 120 parturients scheduled for repeat elective cesarean delivery (passive warming, n = 60 vs. active + passive warming, n = 60) in a retrospective observational cohort study. The primary outcomes of interest were core temperature at the end of the procedure and a decrease in inadvertent perioperative hypothermia (< 36 °C). Secondary outcomes were surgical site infections and adverse markers of neonatal outcome.

Results

The mean temperature at the end of surgery after instituting the active warming protocol was 36.0 ± 0.5 °C (mean ± SD, 95% CI 35.9–36.1) vs. 35.4 ± 0.5 °C (mean ± SD, 95% CI 35.3–35.5) compared to passive warming techniques (p <  0.001) and the incidence of inadvertent perioperative hypothermia at the end of the procedure was less in the active warming group - 68% versus 92% in the control group (p <  0.001). There was no difference in surgical site infections or neonatal outcomes.

Conclusions

Perioperative active warming in combination with passive warming techniques was associated with a higher maternal temperature and lower incidence of inadvertent perioperative hypothermia with no detectable differences in surgical site infections or indicators of adverse neonatal outcomes.

Body temperature at nursery admission in a cohort of healthy newborn infants: results from an observational cross-sectional study

BACKGROUND

Exposure to hypothermia is somehow unavoidable when a baby comes to life. This is the reason why any possible effort should be made by every caregiver involved during birth, from labour to transfer into the maternity ward, to reduce it. Hypothermia has widely shown to be related to several neonatal problems, and the risks are more relevant when the babies are born prematurely.

METHOD

An observational study was conducted in April 2016 to assess the current practises to avoid hypothermia at birth in 20 Italian neonatal units. Each unit introduced local improvements in clinical practice and the same observational study was repeated 1 year later.

RESULTS

A total of 4722 babies were analysed. An overall increase in adherence to local and international recommendations emerged from our study. Significant differences between 2016 and 2017 were found in regard to neonatal temperature at nursery entry (36.3 °C vs 36.5 °C, respectively, p < 0.0001), delayed cord clamping practice > 60″ (48.1% vs 68.1%, respectively, p < 0.0001) and skin-to-skin practice > 60' (56.3% vs 60.9, respectively, p = 0.03). Statistical correlations with the risk of hypothermia were found for delivery room (OR 0.88 (CI 95%0.83-0.94), p < 0.0001) and maternal temperature (OR 0.57 (CI 95% 0.48-0.67), p < 0.0001).

CONCLUSION

Periodical assessment of the delivery room practice has shown to be effective in improving adherence to the international recommendations. Relationship between neonatal hypothermia and several other variables including the delivery room and mother temperature underlines how neonatal thermoregulation starts immediately after birth. Hence, a multi-disciplinary approach is needed to provide the optimal environment for a safe birth.

Effects of combined warmed preoperative forced-air and warmed perioperative intravenous fluids on maternal temperature during cesarean section: a prospective, randomized, controlled clinical trial

Background

Preventing the frequent perioperative hypothermia incidents that occur during elective caesarean deliveries would be beneficial. This trial aimed at evaluating the effect of preoperative forced-air warming alongside perioperative intravenous fluid warming in women undergoing cesarean sections under spinal anesthesia.

Methods

We randomly allocated 135 women undergoing elective cesarean deliveries to either the intervention group (preoperative forced-air and intravenous fluid warming, n = 69) or the control group (no active warming, n = 66). The primary outcome measure was the core temperature change between groups from baseline to the end of the surgical procedure. Secondary outcomes included thermal comfort scores, the incidences of shivering and hypothermia (< 36 °C), the core temperature on arrival at the post-anesthesia care unit, neonatal axillary temperature at birth, and Apgar scores.

Results

Two-way repeated measures ANOVA revealed significantly different core temperature changes (from the pre-spinal temperature to that at the end of the procedure) between groups (F = 13.022, P < 0.001). The thermal comfort scores were also higher in the intervention group than in the control group (F = 9.847, P = 0.002). The overall incidence of perioperative hypothermia was significantly lower in the intervention group than in the control group (20.6% vs. 51.6%, P < 0.0001).

Conclusions

Warming preoperative forced-air and perioperative intravenous fluids may prevent maternal hypothermia, reduce maternal shivering, and improve maternal thermal comfort for patients undergoing cesarean sections under spinal anesthesia.

Trial registration

The study was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR1800019117) on October26, 2018.

Antecedents and outcomes of hypothermia at admission to the neonatal intensive care unit

Objective: To evaluate the association between morbidities preceding and following neonatal intensive care unit (NICU) admission with hypothermia.Study design: NICU admission temperatures for 1271 infants admitted to the NICU at Tufts Medical Center (TMC) between 2012 and 2015 were compared to all Vermont Oxford Network (VON) centers in 2014. We analyzed demographic data, prevalence of hypothermia, and associations with prenatal and neonatal morbidities.Result: Prevalence of hypothermia at TMC was 19% compared to 25% in the VON. We found a significant association between hypothermia and maternal race, birth weight, gestational age, antenatal steroids, chorioamnionitis, mode of delivery, and Apgar scores.Conclusion: Continued emphasis should be placed on avoiding neonatal hypothermia during the first hours of postnatal life.

[Skin-to-skin during caesarean section: Assessment of professional practices]

BACKGROUND

Considering its benefits, immediate skin-to-skin should be applied irrespective of the way of delivery. While it is increasingly applied in case of vaginal delivery, it remains difficult to implement in case of caesarean section.

OBJECTIVE

To estimate the degree of implementation of skin-to-skin in case of caesarean section.

METHODS

Survey in immediate postpartum with a continuous series of patients having given birth by caesarean - whether scheduled or not - in a level 3 hospital systematically realizing skin-to-skin in case of vaginal delivery. The patients were included if the caesarean section had been realized between 16/11/17 and 28/11/17.

RESULTS

Thirty-five women gave birth by caesarean section during the period of study, among which 26 were planned (74%). The emergency levels were varied: 18 had a green code (51%), 12 an orange code (34%) and 5 a red code (14%). Forty-six percent of the newborn children were placed skin-to-skin. The frequency of skin-to-skin was closely linked to the planned character of the caesarean section (89 vs. 31%, P=0.005), as well as its color code (green 72%, orange 25%, red 0%). In case of impossibility to realize skin-to-skin in the course of the caesarean, the reasons were mainly related to the maternal state (63%) (malaise, bleeding, pain). In this situation, skin-to-skin was proposed to the spouse in 83% of cases and realized in recovery room with the mother in 82% of the cases.

CONCLUSION

Skin-to-skin is feasible during caesarean section, regardless of the color code of the procedure.

The effects of crystalloid warming on maternal body temperature and fetal outcomes: a randomized controlled trial

Background and objectives

Hypothermia occurs in about 60% of patients under anesthesia and is generally not managed properly during short lasting surgical procedures. Hypothermia is associated with adverse clinical outcomes. The current study is designed to assess the effects of crystalloid warming on maternal and fetal outcomes in patients undergoing elective cesarean section with spinal anesthesia.

Methods

In this prospective randomized controlled trial, sixty parturients scheduled for elective cesarean section with spinal anesthesia were randomly allocated to receive crystalloid at room temperature or warmed at 37 °C. Spinal anesthesia was performed at L3–L4 interspace with 10 mg of hyperbaric bupivacaine without adding opioids. Core temperature, shivering, and hemodynamic parameters were measured every minute until 10th minute and 5-min intervals until the end of operation. The primary outcome was maternal core temperature at the end of cesarean section.

Results

There was no difference for baseline tympanic temperature measurements but the difference was significant at the end of the operation (p = 0.004). Core temperature was 36.8 ± 0.5 °C at baseline and decreased to 36.3 ± 0.5 °C for isothermic warmed crystalloid group and baseline tympanic core temperature was 36.9 ± 0.4 °C and decreased to 35.8 ± 0.7 °C for room temperature group at the end of the operation. Shivering was observed in 43.3% in the control group. Hemodynamic parameter changes and demographic data were not significant between groups.

Conclusions

Isothermic warming crystalloid prevents the decrease in core temperature during cesarean section with spinal anesthesia in full-term parturients. Fetal Apgar scores at first and fifth minute are higher with isothermic warming.

[The effects of crystalloid warming on maternal body temperature and fetal outcomes: a randomized controlled trial]

BACKGROUND AND OBJECTIVES

Hypothermia occurs in about 60% of patients under anesthesia and is generally not managed properly during short lasting surgical procedures. Hypothermia is associated with adverse clinical outcomes. The current study is designed to assess the effects of crystalloid warming on maternal and fetal outcomes in patients undergoing elective cesarean section with spinal anesthesia.

METHODS

In this prospective randomized controlled trial, sixty parturients scheduled for elective cesarean section with spinal anesthesia were randomly allocated to receive crystalloid at room temperature or warmed at 37°C. Spinal anesthesia was performed at L3-L4 interspace with 10mg of hyperbaric bupivacaine without adding opioids. Core temperature, shivering, and hemodynamic parameters were measured every minute until 10th minute and 5-min intervals until the end of operation. The primary outcome was maternal core temperature at the end of cesarean section.

RESULTS

There was no difference for baseline tympanic temperature measurements but the difference was significant at the end of the operation (p=0.004). Core temperature was 36.8±0.5°C at baseline and decreased to 36.3±0.5°C for isothermic warmed crystalloid group and baseline tympanic core temperature was 36.9±0.4°C and decreased to 35.8±0.7°C for room temperature group at the end of the operation. Shivering was observed in 43.3% in the control group. Hemodynamic parameter changes and demographic data were not significant between groups.

CONCLUSIONS

Isothermic warming crystalloid prevents the decrease in core temperature during cesarean section with spinal anesthesia in full-term parturients. Fetal Apgar scores at first and fifth minute are higher with isothermic warming.

Interventions to prevent hypothermia at birth in preterm and/or low birth weight infants

BACKGROUND

Newborn admission temperature is a strong predictor of outcomes across all gestations. Hypothermia immediately after birth remains a worldwide issue and, if prolonged, is associated with harm. Keeping preterm infants warm is difficult even when recommended routine thermal care guidelines are followed in the delivery room.

OBJECTIVES

To assess the efficacy and safety of interventions designed for prevention of hypothermia in preterm and/or low birth weight infants applied within 10 minutes after birth in the delivery room, compared with routine thermal care or any other single/combination of intervention(s) also designed for prevention of hypothermia in preterm and/or low birth weight infants applied within 10 minutes after birth in the delivery room.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 5), MEDLINE via PubMed (1966 to 30 June 2016), Embase (1980 to 30 June 2016), and CINAHL (1982 to 30 June 2016). We also searched clinical trials databases, conference proceedings, and reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

Trials using randomised or quasi-randomised allocations to test interventions designed to prevent hypothermia (apart from 'routine' thermal care) applied within 10 minutes after birth in the delivery room for infants at < 37 weeks' gestation and/or birth weight ≤ 2500 grams.

DATA COLLECTION AND ANALYSIS

We used Cochrane Neonatal methods when performing data collection and analysis.

MAIN RESULTS

Twenty-five studies across 15 comparison groups met the inclusion criteria, categorised as: barriers to heat loss (18 studies); external heat sources (three studies); and combinations of interventions (four studies).Barriers to heat loss Plastic wrap or bag versus routine carePlastic wraps improved core body temperature on admission to the neonatal intensive care unit (NICU) or up to two hours after birth (mean difference (MD) 0.58°C, 95% confidence interval (CI) 0.50 to 0.66; 13 studies; 1633 infants), and fewer infants had hypothermia on admission to the NICU or up to two hours after birth (typical risk ratio (RR) 0.67, 95% CI 0.62 to 0.72; typical risk reduction (RD) -0.25, 95% CI -0.29 to -0.20; number needed to treat for an additional beneficial outcome (NNTB) 4, 95% CI 4 to 5; 10 studies; 1417 infants). Risk of hyperthermia on admission to the NICU or up to two hours after birth was increased in infants in the wrapped group (typical RR 3.91, 95% CI 2.05 to 7.44; typical RD 0.04, 95% CI 0.02 to 0.06; number needed to treat for an additional harmful outcome (NNTH) 25, 95% CI 17 to 50; 12 studies; 1523 infants), but overall, fewer infants receiving plastic wrap were outside the normothermic range (typical RR 0.75, 95% CI 0.69 to 0.81; typical RD -0.20, 95% CI -0.26 to -0.15; NNTH 5, 95% CI 4 to 7; five studies; 1048 infants).Evidence was insufficient to suggest that plastic wraps or bags significantly reduce risk of death during hospital stay or other major morbidities, with the exception of reducing risk of pulmonary haemorrhage.Evidence of practices regarding permutations on this general approach is still emerging and has been based on the findings of only one or two small studies.External heat sourcesEvidence is emerging on the efficacy of external heat sources, including skin-to-skin care (SSC) versus routine care (one study; 31 infants) and thermal mattress versus routine care (two studies; 126 infants).SSC was shown to be effective in reducing risk of hypothermia when compared with conventional incubator care for infants with birth weight ≥ 1200 and ≤ 2199 grams (RR 0.09, 95% CI 0.01 to 0.64; RD -0.56, 95% CI -0.84 to -0.27; NNTB 2, 95% CI 1 to 4). Thermal (transwarmer) mattress significantly kept infants ≤ 1500 grams warmer (MD 0.65°C, 95% CI 0.36 to 0.94) and reduced the incidence of hypothermia on admission to the NICU, with no significant difference in hyperthermia risk.Combinations of interventionsTwo studies (77 infants) compared thermal mattresses versus plastic wraps or bags for infants at ≤ 28 weeks' gestation. Investigators reported no significant differences in core body temperature nor in the incidence of hypothermia, hyperthermia, or core body temperature outside the normothermic range on admission to the NICU.Two additional studies (119 infants) compared plastic bags and thermal mattresses versus plastic bags alone for infants at < 31 weeks' gestation. Meta-analysis of these two studies showed improvement in core body temperature on admission to the NICU or up to two hours after birth, but an increase in hyperthermia. Data show no significant difference in the risk of having a core body temperature outside the normothermic range on admission to the NICU nor in the risk of other reported morbidities.

AUTHORS' CONCLUSIONS

Evidence of moderate quality shows that use of plastic wraps or bags compared with routine care led to higher temperatures on admission to NICUs with less hypothermia, particularly for extremely preterm infants. Thermal mattresses and SSC also reduced hypothermia risk when compared with routine care, but findings are based on two or fewer small studies. Caution must be taken to avoid iatrogenic hyperthermia, particularly when multiple interventions are used simultaneously. Limited evidence suggests benefit and no evidence of harm for most short-term morbidity outcomes known to be associated with hypothermia, including major brain injury, bronchopulmonary dysplasia, retinopathy of prematurity, necrotising enterocolitis, and nosocomial infection. Many observational studies have shown increased mortality among preterm hypothermic infants compared with those who maintain normothermia, yet evidence is insufficient to suggest that these interventions reduce risk of in-hospital mortality across all comparison groups. Hypothermia may be a marker for illness and poorer outcomes by association rather than by causality. Limitations of this review include small numbers of identified studies; small sample sizes; and variations in methods and definitions used for hypothermia, hyperthermia, normothermia, routine care, and morbidity, along with lack of power to detect effects on morbidity and mortality across most comparison groups. Future studies should: be adequately powered to detect rarer outcomes; apply standardised morbidity definitions; focus on longer-term outcomes, particularly neurodevelopmental outcomes.

Predictive factors of maternal hypothermia during Cesarean delivery: a prospective cohort study

PURPOSE

Although perioperative hypothermia may increase maternal morbidity, active warming is infrequently performed to maintain normothermia during Cesarean delivery (CD). The aim of this prospective observational study was to determine the factors associated with maternal hypothermia in this setting.

METHODS

Women scheduled for elective or emergency CD were consecutively included in this study from November 2014 to October 2015. Maternal temperature was measured using an infrared tympanic thermometer on the patient's arrival in the operating room, at skin incision, and at the end of skin suture. Maternal hypothermia was defined by tympanic temperature < 36°C at the end of skin suture. Univariate analysis was performed, followed by multivariate logistic regression analysis, in order to determine the factors associated with maternal hypothermia at the end of the surgery.

RESULTS

Three hundred fifty-nine women were included and analyzed during this study. The incidence of hypothermia was 23% (95% confidence interval, 18 to 27) among the total population included. According to multivariate analysis, obesity, oxytocin augmentation of labour, and use of active forced-air warming were associated with a decreased risk of maternal hypothermia, while maternal temperature < 37.1°C on arrival in the operating room, maternal temperature < 36.6°C at skin incision, and an infused volume of fluids > 650 mL were significantly associated with maternal hypothermia. Both goodness of fit and predictive value of multivariate analysis were high.

CONCLUSION

Several predictive factors for maternal hypothermia during CD were identified. These factors should be taken into account to help prevent maternal hypothermia during CD.

Early skin-to-skin contact after cesarean section: A randomized clinical pilot study

Objective

Early bonding by skin-to-skin contact (SSC) has been demonstrated to be beneficial for mothers and newborns following vaginal delivery. The aim of this study was to investigate the impact of intraoperative bonding (early SSC) after cesarean section on neonatal adaptation, maternal pain and stress response.

Study design

This prospective, randomized-controlled pilot study was performed at a single academic tertiary hospital (Department of Obstetrics and Gynecology, Medical University of Graz, Austria) between September 2013 and January 2014. Women were randomly assigned to intraoperative (“early”) SCC (n = 17) versus postoperative (“late”) SCC (n = 18). Main variables investigated were neonatal transition (Apgar score, arterial oxygen saturation, heart rate and temperature), maternal pain perception and both maternal and neonatal stress response by measuring the stress biomarkers salivary free cortisol and salivary alpha amylase.

Results

There was no evidence for differences in parameters reflecting neonatal transition or stress response between the ‘Early SSC Group’ and the ‘Late SSC Group’. Maternal salivary cortisol and alpha-amylase levels as well as maternal wellbeing and pain did not differ between the groups. However, the rise of maternal salivary alpha-amylase directly after delivery was higher in the ‘Early SSC Group’ compared to the ‘Late SSC Group’ (p = 0.004).

Conclusions

This study did not reveal significant risks for the newborn in terms of neonatal transition when early SSC is applied in the operating room. Maternal condition and stress marker levels did not differ either, although the rise of maternal salivary alpha-amylase directly after delivery was higher in the ‘Early SSC Group’ compared to the ‘Late SSC Group’, which may indicate a stressor sign due to intensive activation of the sympathetic-adreno-medullary-system. This needs to be further evaluated in a larger prospective randomized trial.

Trial registration

ClinicalTrials.gov NCT01894880

Effectiveness of active and passive warming for the prevention of inadvertent hypothermia in patients receiving neuraxial anesthesia: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Perioperative hypothermia is a common complication of anesthesia that can result in negative outcomes. The purpose of this review is to answer the question: Does the type of warming intervention influence the frequency or severity of inadvertent perioperative hypothermia (IPH) in surgical patients receiving neuraxial anesthesia?

DESIGN

Systematic review and meta-analysis.

SETTING

Perioperative care areas.

PATIENTS

Adults undergoing surgery with neuraxial anesthesia.

INTERVENTION

Perioperative active warming (AW) or passive warming (PW).

MEASUREMENTS

PubMed, CINAHL, Embase, and Cochrane Central Register of Controlled Trials were searched. Inclusion criteria were: randomized controlled trials; adults undergoing surgery with neuraxial anesthesia; comparison(s) of AW and PW; and temperature measured at end of surgery/upon arrival in the Postanesthesia Care Unit. Exclusion criteria were: no full-text available; not published in English; studies of: combined neuraxial and general anesthesia, warm intravenous or irrigation fluids without using AW, and rewarming after hypothermia. Two independent reviewers screened abstracts and titles, and selected records following full-text review. The Cochrane Collaboration's tool for assessing risk of bias was used to evaluate study quality. A random-effects model was used to calculate risk ratios for dichotomous data and mean differences for continuous data.

MAIN RESULTS

Of 1587 records, 25 studies (2048 patients) were included in the qualitative synthesis. Eleven studies (1189 patients) comparing AW versus PW were included in the quantitative analysis. Meta-analysis found that intraoperative AW is more effective than PW in reducing the incidence of IPH during neuraxial anesthesia (RR=0.71; 95% CI 0.61-0.83; p<0.0001; I²=32%). The qualitative synthesis revealed that IPH continues despite current AW technologies.

CONCLUSIONS

During neuraxial anesthesia, AW reduces IPH more effectively than PW. Even with AW, IPH persists in some patients. Continued innovation in AW technology and additional comparative effectiveness research studying different AW methods are needed.

Early skin-to-skin contact for mothers and their healthy newborn infants

BACKGROUND

Mother-infant separation post birth is common. In standard hospital care, newborn infants are held wrapped or dressed in their mother's arms, placed in open cribs or under radiant warmers. Skin-to-skin contact (SSC) begins ideally at birth and should last continually until the end of the first breastfeeding. SSC involves placing the dried, naked baby prone on the mother's bare chest, often covered with a warm blanket. According to mammalian neuroscience, the intimate contact inherent in this place (habitat) evokes neuro-behaviors ensuring fulfillment of basic biological needs. This time frame immediately post birth may represent a 'sensitive period' for programming future physiology and behavior.

OBJECTIVES

To assess the effects of immediate or early SSC for healthy newborn infants compared to standard contact on establishment and maintenance of breastfeeding and infant physiology.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (17 December 2015), made personal contact with trialists, consulted the bibliography on kangaroo mother care (KMC) maintained by Dr Susan Ludington, and reviewed reference lists of retrieved studies.

SELECTION CRITERIA

Randomized controlled trials that compared immediate or early SSC with usual hospital care.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. Quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

We included 46 trials with 3850 women and their infants; 38 trials with 3472 women and infants contributed data to our analyses. Trials took place in 21 countries, and most recruited small samples (just 12 trials randomized more than 100 women). Eight trials included women who had SSC after cesarean birth. All infants recruited to trials were healthy, and the majority were full term. Six trials studied late preterm infants (greater than 35 weeks' gestation). No included trial met all criteria for good quality with respect to methodology and reporting; no trial was successfully blinded, and all analyses were imprecise due to small sample size. Many analyses had statistical heterogeneity due to considerable differences between SSC and standard care control groups. Results for womenSSC women were more likely than women with standard contact to be breastfeeding at one to four months post birth, though there was some uncertainty in this estimate due to risks of bias in included trials (average risk ratio (RR) 1.24, 95% confidence interval (CI) 1.07 to 1.43; participants = 887; studies = 14; I² = 41%; GRADE: moderate quality). SSC women also breast fed their infants longer, though data were limited (mean difference (MD) 64 days, 95% CI 37.96 to 89.50; participants = 264; studies = six; GRADE:low quality); this result was from a sensitivity analysis excluding one trial contributing all of the heterogeneity in the primary analysis. SSC women were probably more likely to exclusively breast feed from hospital discharge to one month post birth and from six weeks to six months post birth, though both analyses had substantial heterogeneity (from discharge average RR 1.30, 95% CI 1.12 to 1.49; participants = 711; studies = six; I² = 44%; GRADE: moderate quality; from six weeks average RR 1.50, 95% CI 1.18 to 1.90; participants = 640; studies = seven; I² = 62%; GRADE: moderate quality).Women in the SCC group had higher mean scores for breastfeeding effectiveness, with moderate heterogeneity (IBFAT (Infant Breastfeeding Assessment Tool) score MD 2.28, 95% CI 1.41 to 3.15; participants = 384; studies = four; I² = 41%). SSC infants were more likely to breast feed successfully during their first feed, with high heterogeneity (average RR 1.32, 95% CI 1.04 to 1.67; participants = 575; studies = five; I² = 85%). Results for infantsSSC infants had higher SCRIP (stability of the cardio-respiratory system) scores overall, suggesting better stabilization on three physiological parameters. However, there were few infants, and the clinical significance of the test was unclear because trialists reported averages of multiple time points (standardized mean difference (SMD) 1.24, 95% CI 0.76 to 1.72; participants = 81; studies = two; GRADE low quality). SSC infants had higher blood glucose levels (MD 10.49, 95% CI 8.39 to 12.59; participants = 144; studies = three; GRADE: low quality), but similar temperature to infants in standard care (MD 0.30 degree Celcius (°C) 95% CI 0.13 °C to 0.47 °C; participants = 558; studies = six; I² = 88%; GRADE: low quality). Women and infants after cesarean birthWomen practicing SSC after cesarean birth were probably more likely to breast feed one to four months post birth and to breast feed successfully (IBFAT score), but analyses were based on just two trials and few women. Evidence was insufficient to determine whether SSC could improve breastfeeding at other times after cesarean. Single trials contributed to infant respiratory rate, maternal pain and maternal state anxiety with no power to detect group differences. SubgroupsWe found no differences for any outcome when we compared times of initiation (immediate less than 10 minutes post birth versus early 10 minutes or more post birth) or lengths of contact time (60 minutes or less contact versus more than 60 minutes contact).

AUTHORS' CONCLUSIONS

Evidence supports the use of SSC to promote breastfeeding. Studies with larger sample sizes are necessary to confirm physiological benefit for infants during transition to extra-uterine life and to establish possible dose-response effects and optimal initiation time. Methodological quality of trials remains problematic, and small trials reporting different outcomes with different scales and limited data limit our confidence in the benefits of SSC for infants. Our review included only healthy infants, which limits the range of physiological parameters observed and makes their interpretation difficult.

Novel bioactive substances in human colostrum: could they play a role in postnatal adaptation?

OBJECTIVE

To determine maternal colostrum/serum concentrations of the bioactive substances irisin, adropin and copeptin and investigate their association with several perinatal parameters and pathologic conditions during pregnancy.

METHODS

In a cohort of 81 mothers with full-term deliveries, colostrum/serum concentrations of irisin, adropin and copeptin were prospectively evaluated by ELISA on Day 3-4 postpartum.

RESULTS

Copeptin and adropin were detectable in human colostrum at higher, while irisin at lower concentrations than in maternal serum (p < 0.001 in all cases). Colostrum adropin and copeptin concentrations positively correlated with maternal serum ones (r = 0.421, p < 0.001 and r = 0.304, p = 0.006, respectively).

CONCLUSIONS

Irisin, adropin and copeptin are present in colostrum and we speculate that they may be implicated in postnatal adaptation with respect to thermoregulation, vascular adaptation, glucose metabolism, lung function and fluid homeostasis. These findings may possibly enhance the necessity for early breastfeeding, particularly of infants born by cesarean section, who are prone to hypothermia, breathing disorders and dehydration.

The impact of ambient operating room temperature on neonatal and maternal hypothermia and associated morbidities: a randomized controlled trial

BACKGROUND

Neonatal hypothermia is common at the time of cesarean delivery and has been associated with a constellation of morbidities in addition to increased neonatal mortality. Additionally, maternal hypothermia is often uncomfortable for the surgical patient and has been associated with intraoperative and postoperative complications. Various methods to decrease the rates of neonatal and maternal hypothermia have been examined and found to have varying levels of success.

OBJECTIVE

We sought to determine whether an increase in operating room temperature at cesarean delivery results in a decrease in the rate of neonatal hypothermia and associated morbidities.

STUDY DESIGN

In this single-center randomized trial, operating room temperatures were adjusted weekly according to a cluster randomization schedule to either 20°C (67°F), which was the standard at our institution, or 23°C (73°F), which was the maximum temperature allowable per hospital policy. Neonatal hypothermia was defined as core body temperature <36.5°C (97.7°F) per World Health Organization criteria. The primary study outcome was neonatal hypothermia on arrival to the admitting nursery. Measures of neonatal morbidity potentially associated with hypothermia were examined.

RESULTS

From February through July 2015, 791 women who underwent cesarean deliveries were enrolled, resulting in 410 infants in the 20°C standard management group and 399 in the 23°C study group. The rate of neonatal hypothermia on arrival to the admitting nursery was lower in the study group as compared to the standard management group: 35% vs 50%, P < .001. Moderate to severe hypothermia was infrequent when the operating room temperature was 23°C (5%); in contrast such hypothermia occurred in 19% of the standard management group, P < .001. Additionally, neonatal temperature in the operating room immediately following delivery and stabilization was also higher in the study group, 37.1 ± 0.6°C vs 36.9 ± 0.6°C, P < .001. We found no difference in rates of intubation, ventilator use, hypoglycemia, metabolic acidemia, or intraventricular hemorrhage. Fever (temperature >38.0°C or 100.4°F) on arrival to the admitting unit was uncommon and did not differ between the study groups. Maternal temperature on arrival to the operating room was not different between the 2 groups, however by delivery it was significantly lower in the standard management group, 36.2 ± 0.6°C vs 36.4 ± 0.6°C, P < .001. This effect persisted, as maternal temperature on arrival to the postoperative care area was lower in the standard management group, 36.1 ± 0.6°C vs 36.2 ± 0.6°C, P < .001, and the rate of hypothermia was higher, 77% vs 69%, P = .008.

CONCLUSION

A modest increase in operating room temperature at the time of cesarean reduces the rate of neonatal and maternal hypothermia. We did not detect a decrease in neonatal morbidity, but the power to detect a small change in these outcomes was limited.

The Effect of patient warming during Caesarean delivery on maternal and neonatal outcomes: a meta-analysis

BACKGROUND

Perioperative warming is recommended for surgery under anaesthesia, however its role during Caesarean delivery remains unclear. This meta-analysis aimed to determine the efficacy of active warming on outcomes after elective Caesarean delivery.

METHODS

We searched databases for randomized controlled trials utilizing forced air warming or warmed fluid within 30 min of neuraxial anaesthesia placement. Primary outcome was maximum temperature change. Secondary outcomes included maternal (end of surgery temperature, shivering, thermal comfort, hypothermia) and neonatal (temperature, umbilical cord pH and Apgar scores) outcomes. Standardized mean difference/mean difference/risk ratio (SMD/MD/RR) and 95% confidence interval (CI) were calculated using random effects modelling (CMA, version 2, 2005).

RESULTS

13 studies met our criteria and 789 patients (416 warmed and 373 controls) were analysed for the primary outcome. Warming reduced temperature change (SMD -1.27°C [-1.86, -0.69]; P=0.00002); resulted in higher end of surgery temperatures (MD 0.43 °C [0.27, 0.59]; P<0.00001); was associated with less shivering (RR 0.58 [0.43, 0.79]; P=0.0004); improved thermal comfort (SMD 0.90 [0.36, 1.45]; P=0.001), and decreased hypothermia (RR 0.66 [0.50, 0.87]; P=0.003). Umbilical artery pH was higher in the warmed group (MD 0.02 [0, 0.05]; P=0.04). Egger's test (P=0.001) and contour-enhanced funnel plot suggest a risk of publication bias for the primary outcome of temperature change.

CONCLUSIONS

Active warming for elective Caesarean delivery decreases perioperative temperature reduction and the incidence of hypothermia and shivering. These findings suggest that forced air warming or warmed fluid should be used for elective Caesarean delivery.