Shoulder Dystocia

Be in the room before it happens - Risk-factor prediction has poor reliability, so let the flags bring you in: diabetes, a previous large-birthweight infant, maternal obesity, prolonged second stage, and failure of descent of the vertex. A bedside sonographic shoulder dystocia measurement of (abdominal circumference divided by pi) minus head circumference greater than 2.6 marks statistically increased risk. These patients get a team briefing that includes anesthesia.

First-line maneuvers don't need a new anesthetic - McRoberts — hyperflexion and slight abduction of the maternal hips, displacing the symphysis 1 to 2 cm cephalad and flattening the sacral promontory — with suprapubic pressure resolves up to 40% of cases by itself. Your job in that first minute is oxygen, hands on the legs, and a functioning epidural, not an induction.

Watch her hips and call out the time - McRoberts complications track directly with time in the position: femoral neuropathy from compression beneath the inguinal ligament, symphyseal separation from excessive hip abduction, and sacroiliac dislocation. With a dense epidural she cannot tell you it hurts, so you are the one who has to notice.

Never fundal pressure - Fundal pressure drives the anterior shoulder harder into the pubic bone and worsens the dystocia. Suprapubic pressure is what is wanted; say it out loud if you see hands on the fundus.

Second-line maneuvers want a surgical-level block - Rotational maneuvers (Rubin, Woodscrew), delivery of the posterior arm, and posterior axillary sling traction are internal maneuvers. Bolus the epidural toward a surgical level — it buys perineal relaxation now and gives you a head start if this becomes a cesarean.

Zavanelli means uterine relaxation and an OR - If the team goes to cephalic replacement, tocolytics such as a halogenated inhaled anesthetic or nitroglycerin assist the replacement. The Zavanelli carries significant maternal morbidity and ends in cesarean delivery, so convert to a surgical anesthetic and move.

Expect to stay for bleeding and repair - Maternal consequences are postpartum hemorrhage and third- or fourth-degree lacerations. Keep oxytocin running and keep the block up for the repair.

Document the sequence - The diagnosis is subjective and the record is what defends it: head-to-body interval, which maneuvers in which order, who was present, and when. Recurrence risk in a subsequent vaginal delivery is roughly 15%, and the literature quotes a 6- to 30-fold increase, so that documentation drives the next delivery plan too.

Shoulder dystocia is a mechanical problem during vaginal delivery: the anterior fetal shoulder impacts behind the maternal pubic symphysis, or less often the posterior shoulder catches on the sacral promontory. It is defined by failure to deliver the shoulders with gentle downward traction alone, the need for additional maneuvers, or a head-to-body interval greater than 60 seconds — that interval is the only objective criterion. It complicates 0.6% to 1.4% of vaginal deliveries.

Fetal macrosomia is the strongest risk factor, followed by pregestational and gestational diabetes, prior shoulder dystocia, and operative vaginal delivery. Prediction from risk factors is unreliable, which is why it arrives as a surprise. Retraction of the head back against the perineum — the turtle sign — is the warning. Once impacted, the clock is running: brachial plexus injury, clavicular or humeral fracture, hypoxic-ischemic encephalopathy, and fetal death are the outcomes at stake.