Vacuum-Associated Scalp Injury

Vacuum associated scalp injury is damage to the baby's scalp from the vacuum cup, ranging from caput succedaneum and chignon to cephalohaematoma, subgaleal haemorrhage, scalp laceration and abrasion. It matters because subgaleal haemorrhage can hide a large part of the baby's blood volume and cause shock and death within hours.

• Risk factors: prolonged application (more than 20 minutes), several detachments, high or rotational vacuum, preterm baby (below 34 weeks), coagulopathy, macrosomia.
• Cephalohaematoma stays within suture lines; subgaleal haemorrhage crosses them.
• Vitamin K at birth lowers the bleeding risk.

A soft swelling under the cup (chignon) is normal and settles in hours. A cephalohaematoma appears hours later as a firm swelling over one bone that does not cross sutures, and subgaleal haemorrhage as a boggy, spreading swelling that crosses sutures and may push the ears forward.

• Pallor, tachycardia, rising head circumference and a fluid wave in subgaleal bleeding.
• Scalp laceration or abrasions at the cup site.
• Differential diagnosis: caput succedaneum, cephalohaematoma, subgaleal haemorrhage, scalp laceration, skull fracture, subdural haemorrhage, scalp abscess, encephalocele.
• Complications: hypovolaemic shock, anaemia, coagulopathy, jaundice from blood breakdown, scalp infection, skull fracture, intracranial haemorrhage, neonatal death, alopecia at the site.

The diagnosis is clinical, with frequent re-examination in the first hours.

• Examine the scalp for swelling position, consistency, spread across sutures and skin damage at 1, 4, 12 and 24 hours.
• Head circumference 4-hourly for 24 hours; pulse, blood pressure, capillary refill, temperature, colour.
• Haemoglobin at 6 and 24 hours, platelets, prothrombin time, activated partial thromboplastin time, fibrinogen, blood group, bilirubin from day 2.
• Cranial ultrasound or CT for neurological signs, skull fracture or seizures.

The principle is observation for caput and cephalohaematoma, and urgent resuscitation and transfusion for subgaleal haemorrhage.

• Supportive: keep warm and monitor in a neonatal unit for any subgaleal swelling; feeding with breast milk; avoid scalp pressure; clean and dress abrasions; gentle handling; no aspiration of a cephalohaematoma.
• Pharmacological: vitamin K 1 mg IM at birth (and again if not given); for subgaleal haemorrhage with shock: sodium chloride 0.9 percent 10 to 20 mL/kg IV over 15 to 30 minutes, packed red cells 10 to 20 mL/kg IV, fresh frozen plasma 10 to 15 mL/kg for coagulopathy, and vitamin K 1 mg IV; phototherapy when bilirubin reaches treatment thresholds (treatment threshold for age and gestation); scalp laceration: clean with sodium chloride 0.9 percent and close with 4/0 absorbable sutures or tissue adhesive if longer than 1 cm; suspected infection of a cephalohaematoma or scalp: benzylpenicillin 50 mg/kg IV 12-hourly plus gentamicin 5 mg/kg IV 24-hourly.
• Procedures: surgical drainage only for an infected cephalohaematoma; exchange transfusion for severe jaundice; neurosurgical review for depressed skull fracture.
• Special groups: preterm babies and babies with bleeding disorders have close monitoring for 48 hours and cranial ultrasound at 24 hours.
• Red flags: spreading swelling crossing sutures, pallor, tachycardia, falling blood pressure, rising head circumference, seizures, rapid jaundice.
• Follow-up: head circumference and haemoglobin daily until stable; cephalohaematoma usually resolves in 2 to 12 weeks; paediatric review at 1 and 6 weeks; ultrasound or X-ray if swelling persists beyond 3 months.