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.

A randomized control trial of bupivacaine and fentanyl versus fentanyl-only for epidural analgesia during the second stage of labor.

BACKGROUND: The purpose of this prospective, double-blinded, parallel-arm, randomized trial was to examine the effects of epidural bupivacaine on the length of the second stage of labor in nulliparous women. METHODS: The authors assessed length of second-stage labor, degree of motor blockade, mode of delivery, and visual analog scores in 310 nulliparous women with labor epidurals randomized to receive either: (1) 0.125% bupivacaine and fentanyl 2 µg/ml or (2) fentanyl 10 µg/ml alone via epidural using double blinding. RESULTS: The median duration of the second stage was 75 min (41, 128) in the bupivacaine/fentanyl group versus 73 min (42, 120) in the fentanyl-only group (P = 0.17) with a median difference of 6.0 (95% CI, -6.0 to 18.0). Furthermore, there was no difference in degree of motor blockade, incidence of operative delivery, visual analog scores, or neonatal outcomes between the two groups. No adverse events were reported. CONCLUSIONS: Use of epidural bupivacaine/fentanyl or a fentanyl-only infusion during the second stage of labor did not affect the duration of the second stage of labor, degree of motor blockade, mode of delivery, pain relief, and maternal or neonatal outcomes. However, in the fentanyl-only infusion group, there was a fivefold increase in opioid exposure to the fetus with unknown effects on neurobehavior, an outcome not assessed beyond the immediate postnatal period in this study.

Continuous Spinal Analgesia for Labor and Delivery: An Observational Study with a 23-Gauge Spinal Catheter.

BACKGROUND: The aim of the study was to assess postdural puncture headache, pain relief, motor blockade, and success rate of conversion to cesarean delivery anesthesia of a 23-gauge spinal catheter (Wiley Spinal®) for labor analgesia. METHODS: After insertion of the spinal catheter, intrathecal bupivacaine 2.5 mg was administered, followed by patient-controlled intrathecal analgesia (basal infusion of 0.0625% bupivacaine with fentanyl 2 µg/mL at a rate of 2 mL/h, demand bolus 1 mL, lockout interval 20 minutes). Bupivacaine 0.5%, up to 25 mg, was administered via the catheter along with fentanyl 20 µg for cesarean delivery anesthesia, if necessary. The catheter was removed after delivery or after 12 hours, whichever was longer. RESULTS: One hundred thirteen women were enrolled. In 12 women (11%), the catheter was not successfully inserted or maintained in position. Continuous spinal analgesia was used in 101 women. Three women (2.6%, 95% confidence interval, 0.7%-8.1%) developed postdural puncture headache. There were 83 spontaneous, 12 operative vaginal, and 18 cesarean deliveries. Of the 18 cesarean deliveries, 16 had continuous spinal analgesia when the decision was made to perform a cesarean delivery; conversion from labor analgesia to cesarean anesthesia was successful in 15 women (94%, 95% confidence interval, 67.7%-99.7%). CONCLUSIONS: The 23-gauge spinal catheter can be used for analgesia for labor. It can also be converted to surgical anesthesia for cesarean deliveries. Further studies are warranted to determine whether the spinal catheter will be a useful addition to the neuraxial techniques available for obstetric anesthesia care.

Active Warming during Cesarean Delivery: Should We SCIP It?

BACKGROUND: The purpose of this open, cluster randomized controlled trial was to evaluate whether use of a fiber optic-regulated warming mattress would decrease the incidence of hypothermia in women undergoing cesarean delivery. PATIENTS AND METHODS: A total of 484 women were randomized via the cluster method on a rotating weekly basis allocating participants to either use of the warming mattress or the standard method of warming at Parkland Hospital (heat-retaining caps, warmed intravenous and irrigation fluids, and warmed blankets). The primary outcome of interest was maternal hypothermia. Surgical site infections and neonatal outcomes were also assessed. RESULTS: The incidence of maternal hypothermia at the conclusion of the surgery was decreased in the warming mattress group, 67 versus 80% in the standard method group (p = 0.013). There were no significant differences in maternal hypothermia at delivery or on arrival to the postanesthesia care unit. The difference in surgical site infections and neonatal outcomes were nonsignificant. CONCLUSION: Use of a warming mattress reduced the incidence of maternal hypothermia at the conclusion of surgery; however, on admission to the postanesthesia care unit, these effects had dissipated.

Differential effects of PPARgamma agonists on the metabolic properties of gliomas and astrocytes.

Recent studies show that thiazolinediones (TZDs), agonists of the peroxisome proliferator-activated receptor gamma (PPARgamma), induce apoptosis in glioma and glioblastoma cells. Here we compared the effects of troglitazone (Trog), a TZD with low affinity for binding to PPARgamma but with potent metabolic effects, on survival and metabolism in GL261 glioma cells versus primary astrocytes. Trog dose-dependently induced cell death in GL261 cells (with over 90% death at 30 microM) but did not cause any toxicity in astrocytes at the same doses. Measurements of glucose and lactate levels after incubation with Trog (30 microM) indicated an overall increase of glucose consumption and lactate production in both cell types. In astrocytes the ratio of lactate produced to glucose utilized was not significantly altered by Trog, while in glioma cells this ratio was decreased by about 40%. Trog dose-dependently reduced mitochondrial membrane potential (DeltaPsi(m)) in both cell types; and the loss of DeltaPsi(m) was greater in the tumor cells (90% loss at 20 microM) than in astrocytes (70% loss at 20 microM). These results suggest that differences in metabolic responses could contribute to the selective resistance of astrocytes to cytotoxic effects of Trog. TZDs such as Trog should therefore be considered for testing in treatment of gliomas.

Diagnosing and managing peripartum headache.

A 38-year-old gravida 7 para 5 Hispanic woman at 36 weeks and 4 days gestation presented with a postpartum headache following vaginal delivery complicated by an unintentional dural puncture for epidural analgesia. Due to the positional nature of the headache and its frontal and occipital origin, a postdural puncture headache was diagnosed. After failure of conservative treatment, an epidural blood patch was used, which offered immediate relief. However, shortly following the procedure, the parturient's neurological condition deteriorated due to an unrecognized intraparenchymal and subarachnoid hemorrhage requiring an emergent craniectomy. This case highlights the importance of diligence when evaluating and treating postpartum headache despite a classic presentation.

Labor complicated by mitral stenosis.

A case where a 28-year-old woman presented in labor complicated by mitral stenosis is described. Mitral stenosis is the most commonly encountered valvular lesion in pregnancy.