Answers

Short answers

1 The initial clinical diagnosis is rectus sheath haematoma.

2 The patient had ongoing haemorrhage that was significant enough to cause anaemia and haemodynamic instability.

3 Urgent investigations include monitoring clotting profile and angiography (computerised tomography angiography or catheter angiography).

4 Specialists from several disciplines should be involved in this case:

a) Cardiologists—to advise on the acceptable clotting parameters given the prosthetic heart valve

b) Haematologists—to advise on control of coagulation

c) Radiologists—to perform computed tomography angiography and embolisation

d) Surgeons—to consider surgical options and the risk of abdominal compartment syndrome.

5 Resuscitation with fluid and blood products should continue following haemodynamic deterioration. Clotting has to be normalised to the minimum level acceptable. Bleeding has to be stopped as soon as possible either by endovascular embolisation or surgery.

Long answers
1 Rectus sheath haematoma
Rectus sheath haematoma is an uncommon condition: a 1999 study reported an incidence of 1.8% among 1257 patients with abdominal pain who needed ultrasound.¹ Rectus sheath haematoma is caused by bleeding into the rectus sheath from damaged superior or inferior epigastric arteries, or from a direct tear of the rectus muscle.² Patients present with abdominal pain and/or a palpable mass (fig 1).³ Further investigation by ultrasound or computed tomography is often necessary to confirm diagnosis. Although usually a self limiting condition, rectus sheath haematoma can cause hypovolaemic shock.^{4 5} Usual causes are abnormal coagulation (that is, as a result of anticoagulant therapy), external trauma, or excessively vigorous contractions of the rectus muscle such as during coughing or twisting.^{2 6}

View larger version (121K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 1 Abdominal wall distension caused by rectus sheath and pelvic haematoma. Initially, only a focal tender bulge in the anterior abdominal wall was present. Green dots show initial size and the purple line the subsequent enlargement

 
2 Ongoing haemorrhage
The patient deteriorated because of ongoing haemorrhage that was significant enough to cause anaemia and haemodynamic instability. Continuous haemorrhage has to be suspected if there is an increase in the size of the abdominal wall mass, a drop in haemoglobin, or haemodynamic instability despite initial resuscitation. The bleeding could have been continuous or may have restarted after a period of time.

3 Urgent investigations
The patient’s coagulation profile and renal function need to be monitored. Both ultrasound and computed tomography scanning can establish the initial diagnosis (figs 2 and 3 ).² Computerised tomography angiography can demonstrate whether there is ongoing bleeding, identify the source of haemorrhage, and allow planning of embolisation therapy (fig 3).⁶ Computerised tomography angiography is becoming the modality of choice in identifying active bleeding, although the more invasive procedure catheter angiography can be used if computerised tomography angiography is not available. Both modalities expose patients to radiation.

View larger version (64K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 2 Ultrasound scan of rectus sheath haematoma. A cystic mass of mixed echogenicity can be seen in the rectus sheath. Note that there is fluid-sediment level with overlying echo free fluid (dark; blood serum), and echogenic sediment (blood cells), typical of a haematoma

 

View larger version (30K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 3 Computed tomogram and angiographic image of rectus sheath haematoma. The axial computed tomogram of the patient’s pelvis shows the rectus sheath haematoma and its extension into the pelvis. An area of contrast extravasation from a small branch of inferior epigastric artery can be seen (arrow). The coronal computed tomogram and the angiographic study also show the area of active haemorrhage (arrows)

 
4 Medical disciplines to involve
Several disciplines should be involved in the management of this patient. Cardiologists should be on hand to advise on the acceptable clotting parameters given the patient’s prosthetic heart valve. Although an INR of 1 is normal, a range of 2-3 should be achieved in patients with prostatic heart valves. Similarly, haematologists should be called to advise on the management of abnormal coagulation status. Radiologists should be available to perform computed tomography angiography and embolisation, whereas surgeons should be consulted on surgical options and the risk of abdominal compartment syndrome.

5 Management after haemodynamic deterioration
Resuscitation with fluid and blood products should take place following haemodynamic deterioration. Clotting abnormalities should be corrected, if possible.

Therapeutic embolisation is a recognised definitive treatment of active haemorrhage. A study of 19 patients treated with catheter embolisation reported 100% technical success of endovascular embolisation in controlling haemorrhage in rectus sheath haematoma.⁶ This technique involves using radiographic guidance to access the bleeding vessel with an arterial catheter (fig 4). This process is performed under local anaesthetic with conscious sedation, thus avoiding the risks of laparotomy and general anaesthetic. A variety of materials (such as coils, particles, and glues) can be used to occlude the afferent and efferent feeders to a bleeding vessel.^{6 7} Completion angiography is used to confirm cessation of haemorrhage.

View larger version (83K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 4 Embolised inferior epigastric artery. The artery is packed with embolisation coils (arrow) and active extravasation of contrast is stopped

 
Patient outcome
This patient poses a paradox: she is bleeding due to excessive anticoagulation (INR=7) yet she is at risk of prosthetic heart valve thrombosis if she does not receive anticoagulation therapy. The advice from the cardiologists was that the patient should not have clotting normalised for more than 2 hours to prevent valve thrombosis. The first step was to bring the INR down to the normal therapeutic range.⁴ The patient was given 2 ml/kg human prothrombin complex (Beriplex; CSL Behring, Marburg, Germany) to reverse the effects of warfarin, and heparin infusion was started.⁴ Embolisation was then used to occlude the bleeding vessel.

Angiography confirmed the exact site of haemorrhage from the inferior epigastric artery. Embolisation was performed successfully using a combination of coils and particles. Blood pressure recovered on the angiography table. Anticoagulation was continued to reduce the risk of valvular thrombosis.

Cite this as: BMJ 2009;339:b2870