Postoperative anaemia and lactic acidosis following open prostatectomy

Postoperative anaemia and lactic acidosis are common surgical complications; however, identifying their cause can be a diagnostic challenge. This narrative review explores the perioperative management of a 70-year-old male patient who had undergone a robot-assisted radical prostatectomy and developed a transient lactic acidosis, as well as persistent postoperative anaemia requiring the transfusion of several units of packed red blood cells following the procedure. Retroperitoneal haemorrhage is a well recognised, although often missed, complication of pelvic surgery and was the identified cause for the fall in haemoglobin levels in this patient. This report explores the challenges in diagnosing retroperitoneal haemorrhage and summarises indications and pitfalls using bedside clinical examination techniques and point-of-care ultrasound, highlighting its low sensitivity for detection of retroperitoneal blood formation. Computed tomography imaging was found to be the imaging modality of choice when the source of bleeding was not apparent, although a cumulative drop in haemoglobin levels or ongoing cardiovascular instability were noted. Alongside this main learning point, further causes and treatment options for postoperative anaemia in otherwise stable patients are illustrated and explained. To investigate a potential connection of low haemoglobin levels to lactate production and acidosis, the oxygen delivery equation is used and other causes of metabolic lactic acidosis are explored.