Operations in the placental and early postpartum periods

Vacuum extraction: essence of the method and instruments

The vacuum extraction method consists of artificially enhancing the mother's expulsive forces. Unlike the application of obstetric forceps, this operation does not replace pushing efforts, but only assists them. That is why it requires the mandatory active participation of the parturient woman.

Historically, obstetrics used the Malmström apparatus with metal cups (ranging from 7.6 to 15.2 cm in diameter) and an electric pump. Due to its high травматичность for the tissues of the fetal head, it is extremely rarely used today. The modern standard is the disposable Kiwi system with a manual vacuum pump. It uses two types of cups:

• Plastic (firm): equipped with an internal foam layer. It is considered universal and provides the most effective fixation.
• Silicone (soft): features a protective cap that is removed immediately before insertion. It is less traumatic, but does not fixate firmly enough on the head.

Indications and absolute contraindications

The procedure is performed for uterine inertia (if drug therapy is ineffective), developing acute fetal distress, low transverse arrest of the sagittal suture, and also for difficult delivery of the head during Caesarean section (CS). Sometimes the method is used for maternal diseases requiring the immediate termination of the second stage of labor.

Strict conditions are necessary for a safe intervention:

1. جنين حي.
2. Full cervical dilation and absence of the amniotic sac.
3. The head being in the narrow part of the pelvic cavity (or at the transition from the wide to the narrow part), when the sagittal suture approaches the direct diameter.

Contraindications include a dead or severely premature fetus, hydrocephalus, anencephaly, and face presentation. A vacuum extractor must not be applied if there is incomplete cervical dilation or high station of the head (pressed to the pelvic inlet or located in the wide part). Furthermore, the method is strictly prohibited in severe maternal pathologies (preeclampsia, eclampsia, hypertension, decompensated heart defects), when pushing efforts must be completely avoided.

Surgical technique and traction rules

No specific preparation is required, but the bladder must be emptied with an elastic catheter. Intravenous and inhalation anesthesia are strictly contraindicated—the woman must push effectively.

Before insertion, the surgeon checks the airtightness of the cup on their palm. The labia are parted with the left hand, and the cup is inserted with the right hand (firm cup by its lateral surface, soft cup in a folded state) and placed on the head. The procedure is performed under strict manual control by the fingers of the vaginal hand to avoid pinching the mother's soft tissues (vaginal walls, edges of the cervix). In the occiput anterior presentation, the center of the Kiwi cup is placed 3 cm posterior to the posterior angle of the large fontanelle.

Initial negative pressure (100 mm Hg) is created using the manual pump, followed by the working pressure (400–600 mm Hg), guided by the green color of the indicator. Tractions are performed strictly synchronously with pushing efforts after a short pause. The direction of traction changes as the head advances:

• Occiput anterior presentation: pulled downward first until the suboccipital region fits under the pubic symphysis, then forward until complete delivery of the head.
• Occiput posterior presentation: tractions downward until the large fontanelle is fixed under the pubic symphysis (1st fixation point, flexion occurs), then backward to deliver the head after the suboccipital pit approaches the coccyx.
• Sinciput (brow) presentation (posterior view): pulled toward oneself until the forehead is fixed under the pubic symphysis (1st fixation point), then forward to deliver the occipital tuber (2nd fixation point), after which the head extends.

If the cup slips off, the attempt can be repeated. If unsuccessful after two times, it is necessary to switch to the application of obstetric forceps. Episiotomy is performed according to indications.

استخراج الجنين من المجيء المقعدي

This manual maneuver is used for the most rapid completion of the 2nd stage of labor in breech presentation. The operation is indicated when the opportunity for a Caesarean section has been missed or as a concluding stage after a classic combined external-internal version of the fetus on the foot.

Depending on the situation, different grip techniques are used:

• In footling or complete breech presentation, the fetus is extracted by one or both legs.
• In frank (pure breech) presentation, the grip is performed by the inguinal fold.

Historically, the method was used for placental abruption (premature separation of a normally implanted placenta), eclampsia, and acute hypoxia. In modern practice, this operation is used predominantly to extract the second twin or upon the birth of a dead fetus.

Conditions for performance are similar to vacuum extraction: full cervical dilation, absence of the amniotic sac, and strict compliance of the mother's pelvic dimensions with the parameters of the subsequent fetal head. However, unlike vacuum extraction, full anesthesia is required here—general intravenous or ongoing regional anesthesia.

باختصار: إجابات عن أسئلة حول الموضوع

أسئلة من المحاضرات والامتحانات

مواضيع أخرى للمراجعة في نفس السياق

• Biomechanism of labor in various types of head engagement
• Technique of performing episiotomy and indications for it
• Fetal complications when using metal cups
• Classic combined internal-internal version of the fetus on the foot
• 특이사항

مواضيع أخرى في قسم «التوليد»

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