Regional complications, such as hemorrhage, infection, and hydrocephalus, or systemic complications, including deep vein thrombosis and septicemia, may follow neurosurgical procedures. Significant morbidity and mortality can result from delaying the diagnosis of these complications or deferring their management. Hospitalists need to be familiar with the most frequently encountered postoperative complications so that they can take immediate and appropriate actions to improve outcomes.

The incidence of postoperative hemorrhage in a survey of 4992 intracranial procedures done in 1988 was estimated to be 0.8%. Of these, intracerebral hemorrhage accounted for 60%, epidural hemorrhage 28%, subdural hemorrhage 7.5%, and intrasellar hemorrhage 5%. In a series of 1771 craniotomies, the incidence of postoperative hematomas requiring surgery was estimated to be 1.4%. Among these 0.7% were epidural, 0.2% subdural, and 0.5% were hemorrhages in the tumor bed. The later type of hemorrhage was fatal in two cases.

Early postoperative hemorrhage from whatever cause usually presents with drowsiness, focal neurologic deficit, or seizure. It can be diagnosed by an urgent CT and often necessitates immediate return to the operating room (OR). Late hemorrhage may be intraparenchymal or subdural at the procedure site or at a remote location. In traumatic brain injury (TBI), coalescence of multiple contusions and small hematomas may form a large hematoma that causes additional mass effect requiring immediate intervention.

Low platelet count, platelet dysfunction, and deficiency of clotting factors as in liver diseases may contribute to postoperative hemorrhage. Severe TBI patients should be screened for coagulopathy because of risk of disseminated intravascular coagulation (DIC) from tissue destruction and release of cerebral thromboplastin. Massive blood transfusion also can cause significant hemolysis, which impedes hemostasis. Hemorrhages are discussed below according to their sites.

Subgaleal Hematoma

Uncontrolled oozing from the main scalp arteries and deep muscles may cause subgaleal hematoma. Presenting as a soft fluctuant mass beneath the scalp, it usually does not require anything more than observation and resolves spontaneously. Rarely, if the hematoma is massive, neurosurgeons perform aseptic aspiration to avoid wound dehiscence.

Epidural Hematoma

The evolution of epidural hematoma (EDH) is most commonly from bleeding, usually arterial, originating from epidural arteries or veins. Indications for surgery include increasing size or symptoms. Alteration of mental status is the most important symptom and an alarm signal to suspect postoperative EDH. The patient may become obtunded, develop contralateral hemiparesis, and contralateral pupillary dilation. An immediate CT scan without contrast confirms the diagnosis. In this setting, the patient should be taken immediately to the operating room for surgical evacuation of the hematoma and control of the bleeding.

Subdural Hematoma

The incidence of postoperative subdural hematoma (SDH) may be reduced with the use of subdural drains. SDH following craniotomy is usually detected incidentally with a CT scan early in the postoperative period. If sufficient mass effect develops from the hematoma, clinical signs may follow within the next few hours. However, the suspicion of postoperative SDH should be raised when a patient develops neurologic deterioration while in the recovery room or in the intensive care unit. Immediate CT scan imaging should guide reoperation.

Asymptomatic patients with postoperative SDH without significant mass effect can be followed clinically and radiologically with the expectation that it will disappear. Rarely, it evolves into chronic SDH.

Patients with a ventricular shunt may develop a subdural hematoma with low pressure. The overall incidence of this type of SDH in adults is 4–23%. The subdural collection can be either ipsilateral to the shunt (32%), on the opposite site (21%), or bilateral (46%). If a nonprogrammable valve was used, it can be replaced with a higher-pressure unit. In nonshunt-dependent cases, the valve can be adjusted, replaced, removed, or temporarily tied. Insertion of an antisiphon device can be also considered.

Parenchymal Hematoma

An intracerebral hemorrhage typically occurs in the bed of a resected tumor. The patient usually presents with symptoms and signs of increased intracranial pressure (ICP) including headache, nausea, vomiting, and alteration in consciousness level. The clinical picture also may be variable according to the site of the hematoma. CT scan is required for the diagnosis. The hematoma size on CT scan and presence of mass effect in addition to the clinical signs determine whether the hematoma is significant. If significant, reexploration with effort to secure hemostasis is required. The hematoma will increase its mass effect over hours to days after it is initially detected.

Ventricular Hemorrhage

Ventricular hemorrhage due to continued ooze of blood into the ventricles may cause headache, vomiting, confusion, and alteration of the consciousness level depending on the severity of the hemorrhage. External ventricular drainage should be considered.

Infection is a potentially problematic postoperative complication. The incidence of postoperative infection is 0.8–7.0% with the use of antibacterial prophylaxis. Without prophylaxis, the incidence is higher. Cephalosporins are currently the preferred antibiotics used for prophylaxis when skin flora (staphylococci) are the likeliest pathogens. Vancomycin is an alternative. In 0.5% of postoperative infection cases, craniotomy is necessary to treat the infection. Presenting symptoms and their frequency in postoperative infection are summarized in Table 64-1.

Postoperative infections can include an infected intracranial device, meningitis, cranial osteomyelitis, brain abscess, subdural empyema, or local wound infection. The causative agents, clinical features, and appropriate management are discussed below for each type.

Infection of Intracranial Device (Shunt Infection)

Shunt infection can be early or late onset. Early shunt infection occurs no later than six months following the device placement. The incidence of early and late infection per procedure is 7% and 6% respectively. Staphylococci are the most common pathogens involved in device infection. The most common route for an early infection is seeding of the device during the operative period. S epidermidis has been estimated to be the culprit in 60–75% of cases. This is followed by S aureus and gram-negative Bacilli. The latter contribute to 6–20% of causes. Late infection occurs almost always due to S epidermidis or propionobacter. It usually occurs due to indolent infection. Rarely, it results from seeding of a vascular shunt during a septicemic episode or colonization during an episode of meningitis.

Clinical features of shunt infection include nonspecific symptoms such as headache, lethargy, and intermittent fever. Meningeal symptoms are often not seen. Shunt dysfunction can also occur, and approximately 29% of patients presenting with shunt dysfunction are found to have positive cultures.

Diagnosis of shunt infection cannot be made on clinical features alone, and definitive diagnosis is made by culture of Cerebrospinal fluid (CSF) either through lumbar puncture or shunt tap. Blood workup will reveal total WBCs above 20,000/mm3 in 30% of patients and increased Erythrosedimentation rate (ESR). Blood culture is positive in less than 33% of patients. CSF analyses reveal a WBC count usually less than 100 cells/mm3. Gram stain is positive in only 50% of CSF samples, and CSF culture is positive in 60% of cases. Head CT scan usually is not helpful, although ependymal enhancement may indicate ventriculitis. Abdominal ultrasound or CT may show a pseudocyst. Treatment of device infection with an antibacterial alone usually has a low success rate, and should be continued for 45 days. It is usually preserved for poor anesthetic candidates. Shunt removal in addition to EVD is the preferred management. The removed device should also be cultured.