Caesarean Wound Haematoma

Caesarean wound haematoma is a collection of blood in the subcutaneous tissue or the rectus sheath at the caesarean incision, caused by bleeding from small vessels (inferior epigastric artery branches) or from coagulopathy. It results from poor haemostasis, anticoagulants, low platelets, hypertension and obesity. It matters because it causes pain, delays healing, and raises the risk of infection, and a rectus sheath haematoma can cause shock.

• Risk factors: anticoagulant use (enoxaparin), low platelets, preeclampsia, HELLP syndrome, obesity, Pfannenstiel incision, coughing and straining, emergency surgery.
• Usually appears within 48 hours.
• Large haematomas need evacuation.

Women have a firm, tender, bruised swelling at the incision with pain, wound ooze and sometimes a falling haemoglobin. A rectus sheath haematoma causes a tender mass below the umbilicus, pain on moving and, if large, shock.

• Swelling, bruising and tenderness along the wound.
• Bluish discoloration extending to the flanks.
• Differential diagnosis: wound infection, wound seroma, bladder flap haematoma, intra-abdominal bleeding, uterine bleeding, subfascial abscess.
• Complications: wound infection and abscess, wound dehiscence, pain, anaemia, shock, delayed healing, scar tenderness.

The diagnosis is made by examination and ultrasound.

• Inspect and palpate the wound; measure the swelling; check for expanding size; assess the abdomen and uterine tone.
• Pulse, blood pressure and temperature; haemoglobin repeated at 6 and 24 hours; platelets, clotting screen.
• Ultrasound: echogenic or mixed collection in the subcutaneous plane or behind the rectus muscle, with its size.
• CT for a large or deep haematoma if the diagnosis is unclear.

The principle is observation for small stable haematomas and evacuation with haemostasis for large or expanding ones.

• Supportive: pressure dressing and abdominal binder; ice packs for 24 hours; rest; mark the swelling and recheck at 6 hours; correct anaemia; hold anticoagulants and restart when bleeding has stopped.
• Pharmacological: paracetamol 1 g oral 6-hourly (maximum 4 g in 24 hours); avoid diclofenac and other NSAIDs while bleeding; tranexamic acid 1 g IV over 10 minutes if bleeding continues; cefazolin 2 g IV as a single dose before evacuation, then amoxicillin-clavulanate 625 mg oral 8-hourly for 5 days for an infected haematoma; transfuse packed red cells for haemoglobin below 7 g/dL or shock; platelets one adult dose for counts below 50 x 10^9/L; fresh frozen plasma 15 mL/kg for coagulopathy; ferrous sulphate 200 mg oral 8-hourly for 3 months.
• Procedures: observation for a haematoma below 5 cm; opening of the wound, evacuation of clot, ligation of bleeding vessels, irrigation and closure with a drain in theatre for larger or expanding haematomas; embolisation of the inferior epigastric artery for a rectus sheath haematoma with active bleeding.
• Red flags: rapid enlargement, falling haemoglobin, shock, severe pain, fever above 38 degrees Celsius, wound breakdown.
• Follow-up: wound review at 48 hours and at 1 week; haemoglobin at 24 hours; ultrasound at 2 weeks if large; review at 6 weeks.