Effect of labor analgesia with nalbuphine hydrochloride on fetal response to vibroacoustic stimulation.

OBJECTIVE

To evaluate the effect of labor analgesia with nalbuphine hydrochloride on the fetal response to vibroacoustic stimulation.

STUDY DESIGN

The response to fetal acoustic stimulation (FAS) was recorded in 27 laboring patients before analgesia. After analgesia with 5 mg nalbuphine hydrochloride administered subcutaneously, the response to FAS was again recorded.

RESULTS

No ominous fetal heart rate (FHR) patterns were observed. FAS reliably increased FHR baseline and long-term FHR variability and produced FHR accelerations. Nalbuphine hydrochloride analgesia did not produce a significant decrease in long-term FHR variability or alter FHR baseline but did reduce the number of FHR accelerations recorded.

CONCLUSION

FAS-induced FHR accelerations did not differ from those observed before analgesia. Analgesia with low doses of nalbuphine did not alter fetal response to FAS, which therefore offers a means of assessing fetal well-being even in the narcotized fetus.