///2009 Abstract Details
2009 Abstract Details2019-08-03T15:55:31-06:00

Maternal forced air-warming prior to and during cesarean section: Effect on maternal temperature and umbilical cord blood gases. Preliminary Results

Abstract Number: 15
Abstract Type: Original Research

Sarah A Starr M.D.1 ; Curtis L Baysinger M.D.2; Ellen M Lockhart M.D.3; Sierra-Anderson Rigoberto M.D.4; Walton Shana M.D.5; Ortega Kelly M.D.6

Introduction: Forced air-warming has been shown in one study to preserve maternal core temperature, decrease shivering, and improve umbilical venous pH in women undergoing elective cesarean delivery(CS) with regional anesthesia1, but not so in another2. We randomized women to receive either forced air-warming(WG=hugger group) or routine care(BG=blanket group) before and during CS.

Methods: After IRB approval, patients undergoing repeat CS with spinal or combined spinal-epidural anesthesia were randomized to WG with forced air temperature(T) set at 43C or offered a blanket(BG) 30 minutes before CS. Maternal demographics reported below were recorded. Neosynephrine(neo) infusion/boluses were titrated to maintain blood pressure at baseline. Shivering instances were scored on a 3 point scale. Thermal comfort and pain were assessed using visual analog scales. 15 minute T readings recorded included bladder T after urinary catheter insertion. Key event times recorded included uterine incision to delivery time (UI-D). All patients received warmed IV fluids. Umbilical artery(UA) and umbilical vein(UV) blood gasses were obtained from a double clamped cord segment. APGAR scores, neonatal weight and T were recorded. Power analysis suggests that 44 randomized patients provide a 90% chance of detecting a UA pH difference of 0.07.

Results: 19 women have been randomized in this ongoing study. Average height/weight/BMI/gravidity/number of prior CS are 157.9cm/ 74kg/ 29/ 3.22/ 1.25 in BG and 165.3cm/ 76kg/ 27.6/ 2.5/ 1.29 in WG. Operating room mean air T are 20.4C in BG and 20.8C in WG. Pain scores at incision/uterine exteriorization are 0/1.2 in BG and 0/0.8 in WG. Shivering instances/mean scores are 11/0.19 in BG and 6/0.09 in WG. Interval comparison of blood pressures is similar between groups. Average neo was 844 g in BG and 600 g in WG. UI-D was 17069 sec in BG and 13852 sec in WG. Neonatal weight is 3.260.21 kg in BG and 3.210.45 kg in WG. Neonatal T is 35.70.31 C in BG and 36.60.44 C in WG. 1/5 minute APGAR scores are 7.8/8.9 in BG and 8.5/9.0 in WG. UA pH/pCO2/pO2/BE are 7.23/62/13/-3.19 in BG and 7.29/54.2/18.3/-1.0 in WG.

Discussion: Descriptive data is presented as collected data at present lacks sufficient power to allow more than the presentation of summary statistics. Comparative data will be presented when enrollment is completed.

References: 1. Horn E-P et. al. Anesth Analg 2002; 94: 409-14. 2. Butwick et.al. Anesth Analg 2007; 105: 1413-9.

SOAP 2009