Researchers investigate effects of fatigue on neurosurgery resident performance

There are more than 6,000 U.S. hospitals, with approximately 3,500 actively practicing board-certified neurosurgeons serving a population of over 303 million people. About 150 neurosurgery residents graduate every year from the 99 accredited U.S. neurosurgery training programs. Since July 2003, residents in most programs have been limited to an 80-hour work week, although in some programs they are allowed to work up to 88 hours. This change was implemented by the Accreditation Council on Graduate Medical Education (ACGME).

The six- or seven-year neurosurgical training program begins with one year of internship and generally ends with one year of chief residency. Neurosurgical residents must acquire extensive knowledge and experience in treating patients with a wide variety of neurological disorders. It is essential that they develop the judgment and ability to assimilate significant and varying technical skills, in order to perform demanding operative procedures, many of which are done on an emergency basis, and can take as long as 16 hours to perform.

Researchers at Feinberg School of Medicine, Northwestern University, University of Arizona College of Medicine, and Arizona State University investigated the effect of fatigue on neurosurgery resident performance. The results of this study, The Effect of Call on Neurosurgery Residents' Skills: Implications for Policy Regarding Resident Call Periods, will be presented by Aruna Ganju, MD, FACS, 5:16 to 5:23 pm, Tuesday, May 4, 2010, during the 78th Annual Meeting of the American Association of Neurological Surgeons in Philadelphia. Co-authors are Kanav Kahol, PhD, Peter Lee, MD, Narina Simonian, BS, Steven J. Quinn, BA, John J. Ferrara, MD, and H. Hunt Batjer, MD, FACS.

In December 2008, the Institute of Medicine recommended that further work hour restrictions be imposed upon resident physicians. In response, the ACGME critically reviewed the benefits of the 80-hour work week restrictions during the first five years of implementation. It was revealed that little data exists regarding the effect of work hour restrictions upon patient safety or resident education. A one-size-fits-all approach to resident duty hours − which assume that all areas of medicine have similar demands and that all resident physicians have a similar set of interests, skills, and endurance − does not account for the unique characteristics required for success in specific areas of medicine.

"While fatigue and its effects on surgical proficiency have been an actively researched area for the last 10 years, past studies have not examined the effect of fatigue on neurosurgery residents specifically. This study aims to quantify the effect of fatigue on the psychomotor and cognitive skills of neurosurgery residents," remarked Dr. Ganju.

Stimulation exercises were designed to measure the resident's cognitive ability such as memory and attention while performing simulated surgical tasks. These exercises were previously validated in several studies including those measuring the impact of fatigue on general surgery residents. Seven residents performed a minimum of two and a maximum of four sessions of six surgical exercises pre-call and post-call. Each exercise measured tool movement smoothness, time elapsed, and cognitive errors. Analysis of Variance (ANOVA) was employed to study the change in surgical skills in pre-call and post-call conditions. "P" less than 0.05 was accepted as a statistically significant difference.

The groups did not show a statistically significant difference in their surgical skills (p values less than 0.3, 0.4, and 0.2 in movement smoothness, time elapsed, and cognitive errors respectively). The mean decrement for all residents in the post-call condition was 8.37 percent.

Post-call fatigue is associated with marginal decrease in surgical proficiency in neurosurgery residents. In a comparative study, general surgery residents showed a statistically significant decrement of 27.3 percent in the post-call condition.

Neurosurgery is a demanding profession and neurosurgeons often find themselves called upon at all hours to treat acutely ill patients, not only saving lives on a daily basis, but helping patients maintain a good quality of life. Numerous adjustments were made by neurosurgical educators seven years ago when the ACGME instituted the maximum 24-hour shift length and 80-hour resident work week. For a specialty such as neurosurgery, further resident work hour restrictions could be detrimental − resulting in neurosurgeons whose training has been compromised − and inevitably leading to patient safety issues.

"The impact of fatigue on different specialties should be further clarified prior to implementation of a national resident physician work hour policy," concluded Dr. Ganju.