Association between surgeon seniority and outcome in intracranial aneurysm surgery

Intraoperative Aneurysm Rupture: Surgical Experience and the Rate of Intraoperative Rupture in a Series of 1000 Aneurysms Operated on by a Single Neurosurgeon

OBJECTIVE

This study aims to examine the risk factors that can cause intraoperative rupture (IOR), and especially, the role of surgical experience. To our knowledge, this is the first study to analyze the effect of the surgeon's experience on the IOR rate in 2 different perspectives.

METHODS

A total of 1000 aneurysms in 775 patients were operated on by a single neurosurgeon. The clinical and radiologic data and intraoperative video recordings of all patients were retrospectively analyzed. To evaluate the role of the surgeon's experience on the IOR rate, the aneurysms were divided chronologically into both 5-year periods and each 100 aneurysms. Number, stage, severity, location, management of IORs, and patients' outcomes were determined.

RESULTS

IOR occurred in 55 aneurysms (5.5% per aneurysm). The incidence of IOR decreased gradually in the first 2 groups of 5-year periods (11.4% and 5.9%, respectively). However, in the last 3 groups, the decline remained stable (4%-5%). Considering all groups, this decrease was statistically significant (P = 0.037). When this evaluation was made for each group of 100 aneurysms, similar results were obtained. Mortality also gradually decreased over the years (P = 0.035). Of 8 possible risk factors, rupture status was found to be the only independent predictor for IOR (OR, 8.68; 95% confidence interval, 3.69-20.47; P <0.001).

CONCLUSIONS

Increased surgical experience reduces the IOR rate from 10%-11% to 4%-5% after an average of 250 aneurysm operations. However, this rate does not decrease further with more experience. To our knowledge, a learning curve regarding IOR is presented for the first time in the literature.

Demystifying the "July Effect" in Plastic Surgery: A Multi-Institutional Study

BACKGROUND

The "July Effect" refers to a theoretical increase in complications that may occur with the influx of inexperienced interns and residents at the beginning of each academic year in July.

OBJECTIVES

We endeavored to determine if a July Effect occurs in plastic surgery.

METHODS

Plastic surgery procedures were isolated from the National Surgical Quality Improvement Program registry. Cases involving residents were grouped as either having occurred within the first academic quarter (AQ1) or remaining year (AQ2-4). Groups were propensity matched using patient/operative factors and procedure type to account for baseline differences. Univariate and multivariate regression analyses assessed differences in overall complications, surgical and medical complications, individual complications, length of hospital stay, and operative time. A comparison group comprised of procedures without resident involvement was also analyzed.

RESULTS

There were 5967 cases with resident involvement, 5156 of which successfully matched. Both univariate and multivariate regression analyses revealed no significant differences between AQ1 and AQ2-4 in terms of overall, surgical, medical and individual complications, or length of hospital stay. There was a statistically significant, albeit not clinically significant, increase in operative time by 10 minutes per procedure during AQ1 in comparison to AQ2-4 (P = 0.001). For procedures lacking resident participation, there were no differences between AQ1 and AQ2-4 in terms of these outcomes.

CONCLUSIONS

A July Effect was not observed for plastic surgery procedures in our study, conceivably due to enhanced resident oversight and infrastructural safeguards. Patients electing to undergo plastic surgery early in the academic year can be reassured of their safety during this period.

Free-hand thoracic pedicle screws placed by neurosurgery residents: a CT analysis

Free-hand thoracic pedicle screw placement is becoming more prevalent within neurosurgery residency training programs. This technique implements anatomic landmarks and tactile palpation without fluoroscopy or navigation to place thoracic pedicle screws. Because this technique is performed by surgeons in training, we wished to analyze the rate at which these screws were properly placed by residents by retrospectively reviewing the accuracy of resident-placed free-hand thoracic pedicle screws using computed tomography imaging. A total of 268 resident-placed thoracic pedicle screws was analyzed using axial computed tomography by an independent attending neuroradiologist. Eighty-five percent of the screws were completely within the pedicle and that 15% of the screws violated the pedicle cortex. The majority of the breaches were lateral breaches between 2 and 4 mm (46%). There was no clinical evidence of neurovascular injury or injury to the esophagus. There were no re-operations for screw replacement. We concluded that under appropriate supervision, neurosurgery residents can safely place free-hand thoracic pedicle screws with an acceptable breach rate.

Lessons learned by personal failures in aneurysm surgery: what went wrong, and why?

PURPOSE

To analyse the intraoperative complications of a single neurosurgeon, with emphasis on devastating intraoperative incidents, and how they possibly could have been avoided.

METHODS

All the patients operated upon by the author between 1986 and 2002, i.e. 252 patients with 270 craniotomies for 294 aneurysms, were included. All intraoperative events that possibly could have influenced the clinical outcome were recorded prospectively.

RESULTS

A total of 16 cases (6.3% of all the patients) with serious intraoperative incidents were identified. In 11 cases (3.6% of all aneurysms), an intraoperative rupture occurred that was judged to have had mild to severe consequences for the patient. In another four patients (1.6% of all patients), all with unruptured, large aneurysms (>15 mm) of the carotid or middle cerebral arteries, a major vessel occlusion occurred inadvertently. In one patient with a large, unruptured MCA aneurysm, a clip slipped after the closure of the wound, causing a fatal intracerebral haemorrhage. These events had a severe impact on the clinical outcome. In retrospect, most of these incidents could, and should have, been avoided.

CONCLUSIONS

It is recommended to start the training of new aneurysm surgeons on patients with small, supratentorial, unruptured aneurysms, followed by ruptured aneurysms in all other supratentorial locations than the anterior communicating artery (ACOM), which is the supratentorial location that should be the last step in the training of independent aneurysm surgeons.

Can a “novice” do aneurysm surgery? Surgical outcomes in a low-volume, non-subspecialised neurosurgical unit

The objective of this paper is to review the results of a junior general neurosurgeon performing aneurysm surgery and compare these to the remainder of his low-volume unit. Prospectively collected data was analysed for 114 aneurysms clipped in 99 patients between July 2001 and May 2005. Overall there was a 0.9% mortality rate and 10.8% complication rate. The favourable outcome rate for the unit was 100% for unruptured aneurysms, 90.4% for grades 1-3 patients and 30% for poor grade patients (grades 4 and 5). The novice neurosurgeon had no mortality and a favourable outcome rate of 94.7% for grades 1-3 patients and 50% for poor grade patients. Acceptable results can be obtained with cerebral aneurysm surgery in a low-volume centre by Australian-trained, non-subspecialty neurosurgeons.

How useful is the 3-dimensional, surgeon’s perspective-adjusted visualisation of the vessel anatomy during aneurysm surgery? A prospective clinical trial

We hypothesized that neuronavigational 3-dimensional display of vessel and aneurysm anatomy, which is adjusted to the actual surgeon's view, could be helpful during the critical steps of aneurysm treatment. A total number of 32 patients with 42 aneurysms entered this prospective clinical trial. With a neuronavigational system, a 3-dimensional image of the arterial vascular anatomy was generated by autosegmentation of a computerized tomography (CT) angiographic data set. The 3-dimensional image was then adjusted to the surgeon's perspective by rotation. The neurosurgeon linked the 3-dimensional image information with the vascular structures in his surgical field by a neuronavigational pointer. He had the opportunity to further rotate the image with the displayed pointer for visualization of hidden structures. After operation, the neurosurgeon had to define with which expectations neuronavigation was applied and to evaluate if these expectations were fulfilled. The expectations with which the neurosurgeon used neuronavigation were to localize the aneurysm (n = 24), to understand the branching anatomy (n = 18), to visualize hidden structures (n = 8), to evaluate the projection of the aneurysm dome (n = 5) and to tailor the approach (n = 2). In 5 of the 42 aneurysms that were either very small or located in close vicinity to the skull base, the neurosurgeon's expectations were not fulfilled. A favorable outcome was achieved in 29 of the 32 patients (91%). Neuronavigational 3-dimensional display of the vessel anatomy was considered useful by the vascular neurosurgeon. Possibly, this technique has the potential to improve operative results by reduction of the surgical trauma and avoidance of intraoperative complications.

Is there a "July phenomenon" in pediatric neurosurgery at teaching hospitals?

OBJECT

Concern for patient safety, among other reasons, recently prompted sweeping changes in resident work policies in the US. Some have speculated that the arrival of new interns and residents at teaching hospitals each July might cause an annual transient increase in poor patient outcomes and inefficient care.

METHODS

Data were analyzed for 4323 craniotomies for tumor resection and 22,072 shunt operations performed in pediatric patients between 1988 and 2000 in US nonfederal hospitals (Nationwide Inpatient Sample, Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality, Rockville, MD). In-hospital mortality rates, discharge outcome, complications, and efficiency measures (length of stay [LOS] and hospital charges) for patients treated in July and August were compared with similar data for patients in other months. There were no significant increases in any adverse end point for either tumor or shunt operations in July and August. Odds ratios (95% confidence interval [CI]) for outcome of tumor craniotomies performed in July and August compared with outcome for tumor craniotomies performed in other months were as follows: for mortality rate, 0.43 (0.14-1.32); for adverse discharge disposition, 1.03 (0.71-1.51); for neurological complications, 1.00 (0.63-1.59); for transfusion, 0.70 (0.41-1.19). Hospital charges were 0.5% lower (range -6 to 5%) in July and August, and LOS was 3% shorter (range -8 to 3%). Odds ratios (95% CI) for July or August shunt surgery compared with shunt surgery performed in other months were as follows: for mortality rate, 0.96 (0.58-1.60); for adverse discharge disposition, 0.85 (0.66-1.11); for neurological complications, 1.27 (0.75-2.16); for transfusion, 0.81 (0.48-1.37). Hospital charges were 0.2% higher in July and August (range -3 to 3%), and LOS was 3% shorter (range -5 to 0.5%).

CONCLUSIONS

Although moderate increases in some adverse end points could not be excluded, there was no evidence that brain tumor or shunt surgery performed in pediatric patients at US teaching hospitals during July and August is associated with more frequent adverse patient outcome or inefficient care than similar surgery performed during other months.

Surgery for primary brain tumors at United States academic training centers: results from the Residency Review Committee for neurological surgery

OBJECT

Surgery for primary brain tumors has been an important index of the quality of neurosurgical training programs in the US. The scope of such cases and the proportion of surgeries performed transsphenoidally are an interesting means of tracking the effectiveness of residency education.

METHODS

Program Information Forms from the 94 American Council for Graduate Medical Education-approved US neurosurgical residency programs were reviewed for the period between 2000 and 2003. Particular attention was focused on an analysis of the cases requiring craniotomy for primary brain tumor and transsphenoidal surgery. The mean annual number of primary brain tumor cases per program was 195, with a range from 36 to 724 cases. The proportion of primary brain tumors accessed transsphenoidally was 20%. The mean annual number of transsphenoidal operations performed at academic training centers was 39. A wide range in the frequency of transsphenoidal cases from one program to another was also noted. Almost one third of training centers performed fewer than 20 transsphenoidal operations annually and 80% performed fewer than 50.

CONCLUSIONS

Most neurosurgical training programs provide residents with excellent experience in craniotomy for primary brain tumors. Practice with transsphenoidal surgery, however, is less well represented and tends to be clustered at several active centers. The implications for neurosurgical education are significant.

Safety of intracranial aneurysm surgery performed in a postgraduate training program: implications for training

OBJECT

Patient care and educational experience have long formed a dichotomy in modem surgical training. In neurosurgery, achieving a delicate balance between these two factors has been challenged by recent trends in the field including increased subspecialization, emerging technologies, and decreased resident work hours. In this study the authors evaluated the experience profiles of neurosurgical trainees at a large Canadian academic center and the safety of their practice on patient care.

METHODS

Two hundred ninety-three patients who underwent surgery for intracranial aneurysm clipping between 1993 and 1996 were selected. Prospective data were available in 167 cases, allowing the operating surgeon to be identified. Postoperative data and follow-up data were gathered retrospectively to measure patient outcomes. In 167 cases, a total of 183 aneurysms were clipped, the majority (91%) by neurosurgical trainees. Trainees performed dissections on aneurysms that were predominantly small (< 1.5 cm in diameter; 77% of patients) and ruptured (64% of patients). Overall mortality rates for the patients treated by the trainee group were 4% (two of 52 patients) and 9% (nine of 100 patients) for unruptured and ruptured aneurysm cases, respectively. Patient outcomes were comparable to those reported in historical data. Staff members appeared to be primary surgeons in a select subset of cases.

CONCLUSIONS

Neurosurgical trainees at this institution are exposed to a broad spectrum of intracranial aneurysms, although some case selection does occur. With careful supervision, intracranial aneurysm surgery can be safely delegated to trainees without compromising patient outcomes. Current trends in practice patterns in neurosurgery mandate ongoing monitoring of residents' operative experience while ensuring continued excellence in patient care.