Adverse Events After Microvascular Decompression: A National Surgical Quality Improvement Program Analysis

BACKGROUND

Although microvascular decompression (MVD) is a durable treatment for medically refractory trigeminal neuralgia, hemifacial spasm, or glossopharyngeal neuralgia attributable to neurovascular conflict, few national studies have analyzed predictors of postoperative complications.

OBJECTIVE

To determine the incidence and risk factors for adverse events after MVD.

METHODS

Patients who underwent MVD were extracted from the prospectively collected National Surgical Quality Improvement Program registry (2006-2017). Multivariable logistic regression identified predictors of 30-day adverse events and unplanned readmission; multivariable linear regression analyzed predictors of a longer hospital stay.

RESULTS

Among the 1005 patients evaluated, the mortality was 0.3%, major neurologic complication rate 0.4%, and 2.8% had a nonroutine hospital discharge. Patient age was not a predictor of any adverse events. Statistically significant independent predictors both of any adverse event (9.2%) and of a longer hospitalization were American Society of Anesthesiologists (ASA) classification III-IV designation and longer operative duration (P ≤ 0.03) The 30-day readmission rate was 6.8%, and the most common reasons were surgical site infections (22.4%) and cerebrospinal fluid leakage (14.3%). Higher ASA classification, diabetes mellitus, and operative time were predictors of readmission (P < 0.04).

CONCLUSIONS

In this National Surgical Quality Improvement Program analysis, postoperative morbidity and mortality after MVD was low. Patient age was not a predictor of postoperative complications, whereas higher ASA classification, diabetes mellitus, and longer operative duration were predictive of any adverse event and readmission. ASA classification provided superior risk stratification compared with the total number of patient comorbidities or laboratory values. These data can assist with preoperative patient counseling and risk stratification.

Fatal complications following microvascular decompression: could it be avoided and salvaged?

Although the microvascular decompression (MVD) surgery has become an effective remedy for cranial nerve rhizopathies, it is still challengeable and may result in a fatal sequel sometimes. Therefore, the operative skill needs to be further highlighted with emphasis on the safety and a preplan for management of postoperative fatal complications should be established. We retrospectively analyzed 6974 cases of MVD. Postoperatively, 46 patients (0.66 %) presented decline in consciousness with a positive finger-nose test (or failure to be tested) after wake up from the anesthesia, whom were focused on in this study. Their surgical findings and intraoperative manipulation as well as computer tomography (CT) delineation were reviewed in detail. These cases consisted of trigeminal neuralgia in 37 and hemifacial spasm in 9. All these patients underwent an immediate CT scan, which demonstrated cerebellar hemorrhages in 38 and epidural hematomas in 6. A later magnetic resource image delineated cerebral infarctions in basal ganglia in 2. Eventually, 15 (0.2 %) died and 31 survived. Data analysis showed that the mortality is significantly higher in trigeminal cases with cerebellar hematoma and an immediate hematoma evacuation plus ventricular drainage could give the patient more chance of survival (p < 0.05). It appeared that the cerebellar hemorrhage was the predominant cause contributable to the postoperative consciousness decline, which occurred more often in trigeminal cases. To have a safe MVD, an appropriate surgical technique is the priority. It is very important to create a satisfactory working space before decompression of the cranial nerve root, which is obtained by a patient microdissection of the arachnoids rather than blind retraction of the cerebellum and hotheaded sacrifice of the petrous vein. Once a cerebellar hematoma is confirmed, an emergency surgery should not be hesitated. A prompt evacuation of the hematomas followed by a dual ventricular drainage via both the frontal horns may save the patient.