Between contractions, some physicians will lower the suction levels to decrease rates of scalp injury, whereas others will maintain suction in cases with a nonreassuring fetal heart rate to aid rapid delivery. No diferences in maternal or fetal outcome were noted if the level of vacuum was decreased between contractions or if an efort was made to prevent fetal loss of station (Boill, 1997). Once the head is extracted, the vacuum pressure is relieved and the cup removed.
Vacuum extraction should be considered a trial. Without early and clear evidence of descent toward delivery, an alternative delivery approach should be considered. As a general guideline, progressive descent should accompany each traction attempt. Neither data nor consensus are available regarding the number of pulls required to efect delivery, the maximum number of cup pop-ofs that can be tolerated, or optimal total duration of the procedure. Some manufacturers have recommendations regarding these in their instructional literature (Clinical Innovations, 2016; CooperSurgical, 2011).
During a vacuum extraction trial, cup dislodgement due to technical failure or less than optimal placement should not be equated with dislodgement under ideal conditions of exact cup placement and optimal vacuum maintenance. hese cases may merit either additional attempts at placement or, alternatively, a trial of forceps (Ezenagu, 1999; Williams, 1991). he least desirable cases are those in which traction without progress or multiple disengagements occur following correct cup application and appropriate traction. As with forceps, clinicians should embrace a willingness to abandon attempts at vacuum extraction if satisfactory progress is not made (American College of Obstetricians and Gynecologists, 2015).
Accreditation Council for Graduate Medical Education: Obstetrics and
Gynecology Case Logs. 20o15. Available at: http://www.acgme.org/Portals/ 0/PDFs/220_NationaLReport_Program_ Version.pdf. Accessed May 11o, 20o16 Aiken AR, Aiken CE, Alberry MS, et al: Management of fetal malposition in the second stage of labor: a propensity score analysis. Amo] Obstet Gynecol 212(3):355.e1,o2015
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