Cephalhaematoma and subgaleal haemorrhage

Overview & Definition

A newborn delivered by vacuum or forceps, or after a long obstructed labour, is noted to have a swelling of the scalp. The question that decides everything is simple: which plane is the blood in? The answer separates a harmless caput from a benign cephalhaematoma from a potentially lethal subgaleal haemorrhage, and it is answered by examining the swelling against the suture lines. [3] [8]

Caput succedaneum is oedema of the soft tissue of the scalp — subcutaneous, present at birth from the pressure of the presenting part against the cervix, crossing the suture lines, pitting on pressure, and resolving over the first days. It is harmless. Cephalhaematoma is a collection of blood between a skull bone and its periosteum — subperiosteal — confined by the attachments of the periosteum to the suture of that bone, so it does not cross the suture line, is firm and non-pitting, and enlarges over the first hours to days. Subgaleal haemorrhage is blood in the loose areolar tissue beneath the galea aponeurotica — the subaponeurotic space — which is a large potential space extending across the whole vault and down to the nape of the neck, so the swelling is diffuse, crosses the sutures and fontanelles, and can hold a volume of blood large enough to exsanguinate a newborn. [3] [6] [8]

The clinical importance of each is set by its plane. The subperiosteal space of a single bone is small and tight — a cephalhaematoma is self-limiting and its blood stays localised, the main late consequences being anaemia and hyperbilirubinaemia as the clot is reabsorbed. The subaponeurotic space is enormous by comparison — it has been estimated to hold a substantial fraction of a newborn's blood volume, which is why a subgaleal haemorrhage is the one scalp bleed that can kill. Recognising which plane you are dealing with, and reacting to the systemic signs of blood loss, is the heart of this topic. [3] [4]

The modern story of these conditions is one of prevention and vigilance. Safer operative vaginal delivery — limits on the number of cup detachments and pulls, abandoning the instrument for a caesarean when delivery does not progress, and alerting the neonatal team whenever a vacuum or forceps has been used — has not abolished subgaleal haemorrhage but has made early recognition the difference between a stable infant and a death. The fellowship candidate is expected to carry both the anatomical reasoning and the disciplined post-instrumental observation protocol. [3] [9] [10]