Pelvic Haemorrhage

Pelvic haemorrhage is life threatening bleeding from pelvic fractures and associated soft tissue injury, most often after high energy blunt trauma. Haemodynamic instability with pelvic fracture carries mortality of 30 to 50%.

Epidemiology. Pelvic fractures occur in about 3 to 8% of blunt trauma. Haemorrhage is the main cause of early death. Older adults can bleed after low energy falls, especially on anticoagulants.

Sources of bleeding. Venous plexus and cancellous bone (about 80 to 90%), and arterial branches of the internal iliac (about 10 to 20%), including the superior gluteal and internal pudendal arteries.

Classification. Anteroposterior compression, lateral compression, vertical shear and combined patterns. Anteroposterior compression with an open pelvis, and vertical shear, carry the highest bleeding risk.

Pathophysiology. The pelvic ring has a large capacity for blood (many litres in the retroperitoneum). Disruption enlarges the volume and prevents tamponade.

Presentation is shock, pelvic and groin pain, leg length or rotational discrepancy, perineal, scrotal or flank bruising, blood at the urethral meatus, and open wounds. Rectal and vaginal examination may show a laceration (open fracture).

Red flags.

• Hypotension with pelvic injury.
• Blood at the urethral meatus, high riding prostate or perineal haematoma (urethral injury).
• Open pelvic fracture, or a wound communicating with the rectum or vagina.

A pelvic radiograph and extended ultrasound examination in the unstable patient. CT with contrast (arterial phase) in stable patients, showing the fracture and contrast extravasation (blush). Do not repeatedly compress or spring the pelvis. Perform a retrograde urethrogram before a urinary catheter if urethral injury is suspected.

Differential diagnosis. Intra-abdominal bleeding, thoracic bleeding, long bone fracture bleeding and spinal injury.

Pelvic binder. Apply a binder or sheet at the level of the greater trochanters (not the iliac crests) to reduce volume. Internally rotate and tie the feet together. Use a binder in any unstable patient with suspected pelvic fracture, and check the skin.

Resuscitation. Two large bore lines, balanced blood products (1 red cell unit to 1 plasma to 1 platelet pool, or whole blood), permissive hypotension (systolic 80 to 90 mmHg) without head injury, warming, calcium (calcium gluconate 10% 20 mL for each 4 units) and tranexamic acid 1 g IV over 10 minutes then 1 g over 8 hours.

Haemorrhage control in the unstable patient.

• Preperitoneal pelvic packing with external fixation.
• Angioembolisation for arterial bleeding (blush on CT or persistent instability), ideally within 60 minutes.
• Resuscitative endovascular balloon occlusion of the aorta in zone 3 as a bridge, limited to short periods (aim under 60 minutes).
• Damage control laparotomy if there is intra-abdominal bleeding.

Fixation. External fixation, pelvic C-clamp for posterior injuries, then definitive internal fixation when physiology allows.

Open fracture. Diverting colostomy, wound debridement, and antibiotics: cefazolin 2 g IV every 8 hours with metronidazole 500 mg IV every 8 hours (add gentamicin 5 mg/kg IV once for gross contamination, adjusted to renal function).

Monitoring. Haemoglobin, lactate, coagulation, temperature, limb perfusion and urine output.

Referral and escalation. Trauma surgery, orthopaedics and interventional radiology at once, and urology for urethral injury.

Special groups. In anticoagulated patients, reverse the anticoagulant. In pregnancy, tilt left and involve obstetrics, and expect higher foetal loss.