procedure

Last reviewed 01/2018

A great advantage of a vacuum extraction is that local infiltration of the perineum with 1% lignocaine is the only analgesia required.

The cup is:

  • introduced sideways into the vagina
  • applied to the foetal scalp close to the posterior fontanelle

Care is taken not include any vaginal or cervical tissue in the vacuum cup.

A negative pressure of 0.8 kg/square cm is applied over 4 minutes. This allows the formation of the chignon, allowing maximum contact of the cup with the scalp.

Traction is applied:

  • perpendicular to the cup or else the cup may become dislodged
  • during uterine contractions

If there is no obvious descent after 4 contractions then a caesarian section should be performed.