///2014 Abstract Details
2014 Abstract Details2019-07-18T14:34:47+00:00

A Single-Blinded Prospective Study Comparing Pain Relief in Laboring Term Parturients Receiving Sedara Versus Butorphanol

Abstract Number: F-04
Abstract Type: Original Research

Mete H Akin D.O., M.P.H.1 ; Helene Finegold M.D.2; Tracey Vogel M.D.3; Christopher Troianos M.D.4

Introduction - Nitrous oxide (N2O) has been used to treat labor pains for over 150 years. Sedara™ is a self-administered, portable gas delivery system which delivers a 50% N2O / 50% oxygen mixture (N2O/O2) by a negative pressure triggering mechanism. We present a single-blinded prospective study comparing the analgesic effect of Sedara versus Butorphanol in laboring term parturients.

Materials and Methods – Healthy term parturients in active labor who requested labor analgesia were approached for study participation. Exclusion criteria included age < 18, cervical dilation ≥ 5 cm, gestational age less than 37 or greater than 41 weeks, analgesic use within the prior 12 hours, multiple gestation pregnancies, and presence of significant maternal co-morbidities. Each participant was blinded to study drug and received either Sedara and placebo injection of 1 mL saline or 1 mg Butorphanol and 100% oxygen placebo over a 60 minute period. Primary outcome measures were collected at 5, 15, 30, and 60 minutes after study initiation and included: pain reduction, nausea, dizziness, and overall satisfaction on a 0-10 visual analog scale (VAS) score.

Results - Nineteen subjects were recruited, 11 receiving Sedara and 8 receiving Butorphanol. There was no difference in demographic data between the two groups, including cervical dilation or pregnancy length. Mean changes in VAS scores were compared to baseline at the pre-determined data collection points during the 60 minute trial and were as follows: (format: N2O/O2, Butorphanol; p-value); pain score reduction (4.21, 2.16; p=0.01), nausea (0.88, 1.03; p=0.74), dizziness (1.98, 2.62; p=0.44), and overall satisfaction (7.32, 4.59; p=0.01).

Conclusions – Sedara showed superior pain reduction and overall satisfaction compared to Butorphanol in early laboring parturients. Coupled with the enhanced safety of this system's negative pressure triggering, Sedara is an attractive analgesic tool in this patient population. Further patient recruitment to adequately power the study will continue at our institution.


1. Collins MR, Starr SA, Bishop JT, Baysinger CL. Nitrous oxide for labor analgesia: expanding analgesic options for women in the United States. Rev Obstet Gynecol. 2012; 5(3-4): e126-31.

2. Rooks JP. Nitrous oxide for pain in labor-why not in the United States? Birth. 2007; 34: 3-5.

3. Rosen MA. Nitrous oxide for relief of labor pain: A systematic review. Am J Obstet gynecol. 2002; 186: S110-126.

SOAP 2014