Complications occur after operations and surgeons must be versed in anticipating, recognizing, and managing them. The spectrum of these complications ranges from the relatively minor, such as a small postoperative seroma, to the catastrophic, such as postoperative myocardial infarction or anastomotic leak. The management of these complications also spans a spectrum from nonoperative strategies to those requiring an emergent return to the operating room.
When considering postoperative complications, it is helpful to categorize them in a system-based method that has additional usefulness in clinical research.
Mechanical complications are defined as those that occur as a direct result of technical failure from a procedure or operation. These complications include postoperative hematoma and hemoperitoneum, seroma, wound dehiscence, anastomotic leak, and those related to lines, drains, and retained foreign bodies.
Wound hematoma, a collection of blood and clot in the wound, is a common wound complication and is usually caused by inadequate hemostasis. The risk is much higher in patients who have been systemically anticoagulated and in those with preexisting coagulopathies. However, patients receiving aspirin or low-dose heparin also have a slightly higher risk of developing this complication. Vigorous coughing or marked arterial hypertension immediately after surgery may contribute to the formation of a wound hematoma.
Hematoma produces elevation and discoloration of the wound edges, discomfort, and swelling. Blood sometimes leaks between skin sutures. Neck hematoma following operation on the thyroid, parathyroid, or carotid artery are particularly dangerous, because it may expand rapidly and compromise the airway. Small hematomas may resorb, but they increase the incidence of wound infection. Treatment in most cases consists of evacuation of the clot under sterile conditions, ligation of bleeding vessels, and reclosure of the wound.
Bleeding is the most common cause of shock in the first 24 hours after abdominal surgery. Postoperative hemoperitoneum—a rapidly evolving, life-threatening complication—is usually the result of a technical problem with hemostasis, but coagulation disorders may play a role. Causes of coagulopathy, such as dilution of hemostatic factors after massive blood loss and resuscitation, mismatched transfusion, or administration of heparin, should also be considered. In these cases, bleeding tends to be more generalized, occurring in the wound, venipuncture sites, etc.
Hemoperitoneum usually becomes apparent within 24 hours after the operation. It manifests as intravascular hypovolemia: tachycardia, hypotension, decreased urine output, and peripheral vasoconstriction. If bleeding continues, abdominal girth may increase and intra-abdominal hypertension or abdominal compartment syndrome may ensue. Changes in the hematocrit are usually not obvious for 4-6 hours and are of limited diagnostic help in patients who sustain rapid blood loss.
Manifestations may be so subtle that the diagnosis is initially overlooked. Only a high index of suspicion, frequent examination of patients at risk, and systematic investigation of patients with postoperative hypotension will reliably result in ...