Nulliparous women with low cervical dilation more likely to need more anaesthetic interventions

A single injection of spinal anaesthesia appears to be enough for multiparous women undergoing spontaneous labour with more advanced cervical dilation, a recent study has found.

Researchers retrospectively reviewed electronic medical records of 428 women (median age, 30 years) who received spinal analgesic blocks for labour. The primary outcome was the need for an additional anaesthetic intervention after the first administration of analgesia. Spinal, epidural and general anaesthesia, as well as intravenous sedation, were counted.

Sixty instances of required additional anaesthetic intervention were reported, resulting in an overall rate of 14.0 percent. The median time to additional administration was 115 minutes. These patients showed significantly longer time to delivery than their counterparts who did not require any additional anaesthetics (222 vs 48 minutes; p<0.001).

Multivariable logistic regression analysis found that higher age (odds ratio [OR] per 5 years, 1.41, 95 percent CI, 1.04–1.90; p=0.025), nulliparity (OR, 3.33, 1.72–6.43; p<0.001) and having low cervical dilation (OR per 1 cm, 0.87, 0.76–1.00; p=0.045) were all significant predictors for needing additional anaesthetic interventions.

Complications were rare (n=9; 2.1 percent) and were limited to postdural puncture headaches. Of those who developed the side effect, more than half (n=5; 55.6 percent) received successful epidural blood patches. There were no reports of neurologic or bleeding complications, and none of the participating women required treatment for pruritus.