///2015 Abstract Details
2015 Abstract Details2019-08-02T16:54:43-06:00

Clinical significance of audible air leakage during labor epidural analgesia: A prospective observational study

Abstract Number: S-75
Abstract Type: Original Research

Sung Uk Choi MD., PhD.1 ; Hyungtae Kim MD., PhD.2; Sang-Hwan Do MD., PhD.3; Hea-Jo Yoon MD., PhD.4


Air leakage sounds are sometimes heard during labor epidural analgesia because the epidural space of pregnant women is under sustained positive pressure. We investigated whether audible air leakage is related to successful labor epidural analgesia using loss of resistance to air technique.


We observed the occurrence of audible air leakage after removing the air syringe or after the Tuohy needle was rotated 90º during labor epidural analgesia in 1,200 parturients. Patients were allocated to the sound (Group S) or no sound group (Group N) according to the occurrence of audible air leakage. Overall failure rate, failure of catheter insertion, unintentional dural puncture, intravenous catheter, paresthesia, inadequate analgesia, catheter migration, and labor pain were investigated.


The incidence of audible air leakage in our sample was 35.9%. Rates of overall epidural failure, unintentional dural puncture, and intravenous catheter were significantly lower and median scores on the numerical rating scale of labor pain were significantly higher in Group S than in Group N. No differences were observed in the incidence of the failure of catheter insertion, temporary paresthesia, replacement due to paresthesia, inadequate epidural analgesia or catheter migration between groups. The presence of air leakage sounds had a positive predictive value of 98.6%, a specificity of 76.2%, and a sensitivity of 38.4% for successful labor analgesia without catheter replacement.


The occurrence of audible air leakage sound after removing the air syringe or after 90º rotation of the Tuohy needle was associated with successful needle placement in the epidural space.

SOAP 2015