Subgaleal hemorrhage, also known as subgaleal hematoma, is bleeding in the potential space between the skull
periosteum
The periosteum is a membrane that covers the outer surface of all bones, except at the articular surfaces (i.e. the parts within a joint space) of long bones. Endosteum lines the inner surface of the medullary cavity of all long bones.
Structure ...
and the scalp
galea aponeurosis
The epicranial aponeurosis (aponeurosis epicranialis, galea aponeurotica) is an aponeurosis (a tough layer of dense fibrous tissue). It covers the upper part of the skull in humans and many other animals.
Structure
In humans, the epicranial ...
.
Symptoms
The diagnosis is generally clinical, with a fluctuant boggy mass developing over the
scalp
The scalp is the anatomical area bordered by the human face at the front, and by the neck at the sides and back.
Structure
The scalp is usually described as having five layers, which can conveniently be remembered as a mnemonic:
* S: The ski ...
(especially over the occiput) with superficial skin
bruising
A bruise, also known as a contusion, is a type of hematoma of tissue, the most common cause being capillaries damaged by trauma, causing localized bleeding that extravasates into the surrounding interstitial tissues. Most bruises occur clos ...
. The
swelling develops gradually 12–72 hours after delivery, although it may be noted immediately after delivery in severe cases. Subgaleal hematoma growth is insidious, as it spreads across the whole calvaria and may not be recognized for hours to days. If enough blood accumulates, a visible fluid wave may be seen. Patients may develop periorbital ecchymosis ("
raccoon eyes
Raccoon eyes (also known in the United Kingdom and Ireland as panda eyes) or periorbital ecchymosis is a sign of basal skull fracture or subgaleal hematoma, a craniotomy that ruptured the meninges, or (rarely) certain cancers. Bilateral hemorrha ...
").
Patients with subgaleal hematoma may present with
hemorrhagic shock
Hypovolemic shock is a form of shock caused by severe hypovolemia (insufficient blood volume or extracellular fluid in the body). It could be the result of severe dehydration through a variety of mechanisms or blood loss. Hypovolemic shock is a ...
given the volume of blood that can be lost into the potential space between the skull periosteum and the scalp galea aponeurosis, which has been found to be as high as 20-40% of the neonatal blood volume in some studies.
The swelling may obscure the
fontanel
A fontanelle (or fontanel) (colloquially, soft spot) is an anatomical feature of the infant human skull comprising soft membranous gaps ( sutures) between the cranial bones that make up the calvaria of a fetus or an infant. Fontanelles allow f ...
and cross cranial
suture lines, distinguishing it from
cephalohematoma
A cephalohaematoma is a hemorrhage of blood between the skull and the periosteum of any age human, including a newborn baby secondary to rupture of blood vessels crossing the periosteum. Because the swelling is subperiosteal, its boundaries are ...
, in which the bleed is confined by its subperiosteal location.
Patients with subgaleal hemorrhage may also have significant
hyperbilirubinemia
Bilirubin (BR) (Latin for "red bile") is a red-orange compound that occurs in the normal catabolic pathway that breaks down heme in vertebrates. This catabolism is a necessary process in the body's clearance of waste products that arise from the ...
due to resorption of hemolyzed blood. Laboratory studies may demonstrate reduced hemoglobin and hematocrit due to blood loss into the subgaleal space, and coagulation studies may reflect an underlying coagulopathy. Mortality has been reported to occur in 12-14% of cases, generally as a consequence of massive blood loss presenting with shock, often in the setting of uncorrected coagulopathy. However, with early identification and prompt treatment, the prognosis is good, and there are usually no long-term consequences.
Causes
The majority of neonatal cases (90%) result from applying a vacuum to the head at delivery (
ventouse
Vacuum extraction (VE), also known as ventouse, is a method to assist delivery of a baby using a vacuum device. It is used in the second stage of labor if it has not progressed adequately. It may be an alternative to a forceps delivery and cae ...
-assisted delivery). The vacuum assist ruptures the
emissary vein
The emissary veins connect the extracranial venous system with the intracranial venous sinuses. They connect the veins outside the cranium to the venous sinuses inside the cranium. They drain from the scalp, through the human skull, skull, into t ...
s (i.e., connections between dural sinus and scalp veins) leading to accumulation of blood under the aponeurosis of the scalp muscle and superficial to the periosteum.
[AAP Textbook of Pediatrics]
Additionally, subgaleal hematoma has a high frequency of occurrence of associated head trauma (40%), such as intracranial hemorrhage or skull fracture. The occurrence of these features does not correlate significantly with the severity of subgaleal hemorrhage.
Diagnosis
Early recognition of this injury is crucial for survival. Infants who have experienced a difficult operative delivery or are suspected to have a SGH require ongoing monitoring including frequent vital signs (minimally every hour), and serial measurements of hematocrits and their occipital frontal circumference, which increases 1 cm with each 40 mL of blood deposited into the subgaleal space. Head imaging, using either CT or MRI, can be useful for differentiating subgaleal hemorrhage from other sources of cranial bleeding. Head ultrasound is useful for the diagnosis of SGH in the hands of an operator experienced in imaging the neonatal head and scalp, and is preferable to CT due to lack of ionizing radiation. Coagulation studies are required to detect coagulopathy that may be associated with the bleeding.
Management
Management consists of vigilant observation over days to detect progression and, if required, manage complications (e.g.
hemorrhagic shock
Hypovolemic shock is a form of shock caused by severe hypovolemia (insufficient blood volume or extracellular fluid in the body). It could be the result of severe dehydration through a variety of mechanisms or blood loss. Hypovolemic shock is a ...
, unconjugated hyperbilirubinemia and
jaundice
Jaundice, also known as icterus, is a yellowish or greenish pigmentation of the skin and sclera due to high bilirubin levels. Jaundice in adults is typically a sign indicating the presence of underlying diseases involving abnormal heme meta ...
from hemolyzed red blood cells). The subgaleal space is capable of holding up to 40% of a newborn baby's blood and can therefore result in acute shock and death. Fluid bolus may be required if blood loss is significant and the patient becomes tachycardic. Transfusion and phototherapy may be necessary. Investigation for
coagulopathy
Coagulopathy (also called a bleeding disorder) is a condition in which the blood's ability to coagulate (form clots) is impaired. This condition can cause a tendency toward prolonged or excessive bleeding (bleeding diathesis), which may occur spo ...
may be indicated.
See also
*
Caput succedaneum
Caput succedaneum is a neonatal condition involving a serosanguinous, subcutaneous, extraperiosteal fluid collection with poorly defined margins caused by the pressure of the presenting part of the scalp against the dilating cervix (tourniquet ef ...
*
Cephal
*
Cephalohematoma
A cephalohaematoma is a hemorrhage of blood between the skull and the periosteum of any age human, including a newborn baby secondary to rupture of blood vessels crossing the periosteum. Because the swelling is subperiosteal, its boundaries are ...
*
Hematoma
A hematoma, also spelled haematoma, or blood suffusion is a localized bleeding outside of blood vessels, due to either disease or trauma including injury or surgery and may involve blood continuing to seep from broken capillary, capillaries. A he ...
References
External links
{{DEFAULTSORT:Subgaleal Hemorrhage
Neurological disorders
Birth trauma