Expert offers Vacuum extraction strategies. (Suggests Stopping After Two Pop-Offs).

KAUAI, HAWAII -- Vacuum extraction gained popularity as a form of operative vaginal delivery in the 1990s despite a lack of formal guidelines on how to do it, Dr. Julian T. Parer said at a conference on obstetrics, gynecology, perinatal medicine, neonatology, and the law.

In 1994, the American College of Obstetricians and Gynecologists offered a general guideline on how to best perform a vacuum extraction: Descent of the fetus should accompany each traction. But ACOG cited a lack of consensus regarding the optimal number of pulls, a limit to the number of times the vacuum cup may pop off before abandoning the procedure, and a maximum time limit for attempted vacuum delivery, he said.

Dr. Parer, director of perinatal medicine and genetics and professor of ob.gyn. at the University of California, San Francisco, offered his own, more detailed recommendations on vacuum extraction at the meeting, which was sponsored by Boston University:

* Place the vacuum cup on the occiput of the fetal cranium toward the anterior fontanelle. Check for vaginal tissue, especially anteriorly, before engaging pressure or traction.

* Bring the vacuum pressure to 100 mm Hg. With contractions, increase the pressure to 600 mm Hg.

* Apply axis traction with maternal pushing for a full minute, using a fetal heart rate monitor to time it. Short pushes are best, and grunting should be encouraged. Try to avoid the yelling or vigorous coaching others in the room may offer when it comes time to push. Vacuum extraction is "a relatively subtle technique. The person doing the traction should be the coach," he said.

Many clinicians at his institution prefer to lower the suction pressure between contractions to reduce pain on the baby's head. Constant ...