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David A McClusky

Publications and source records attributed to David A McClusky.

12 recordsLinked to original sources
PubMed2006

Groin hernia: anatomical and surgical history.

The history of surgical repair of groin hernia is a lengthy record of assorted techniques in search of a cure for an ailment that comes in many sizes and shapes and that has plagued humanity for thousands of years. Although improvements are still being sought and found, for several decades surgeons have had the means to relieve most hernia sufferers. A remaining issue is whether the wide array of surgical procedures can or should be whittled down to a few "standard" operations that are safe, effective, and cost-efficient. The history of the anatomy of groin hernia shows how much there was to learn and how much remains to be learned. It also shows how important it is for the surgeon to know and understand both the anatomy of the area and the formation of groin hernia.

Anatomy↗
PubMed2006

Perceptual, visuospatial, and psychomotor abilities correlate with duration of training required on a virtual-reality flexible endoscopy simulator.

BACKGROUND: Trainees acquire endoscopic skills at different rates. Fundamental abilities testing could predict the amount of training required to reach a performance goal on a virtual-reality simulator. METHODS: Eleven medical students were tested for fundamental abilities. Baseline endoscopic proficiency was evaluated with the GI Mentor II VR simulator (Simbionix, USA, Cleveland, OH). Subjects trained on the simulator with a defined performance goal. Subjects who achieved the goal were then reassessed. RESULTS: All subjects completed at least 10 trials or reached the performance goal. The <10 trial group (n=6) tested better for all fundamental abilities and baseline endoscopic performance than the >10 trial group (n=5). The number of trials required to reach the performance goal correlated significantly with both perceptual (r=.92, P=0.001) and visuospatial ability (r=.76, P=.03). Multiple regression showed strong correlation of all three abilities with duration of training (r=.95, P=.015). CONCLUSIONS: Most of the variability in acquisition of endoscopic skills can be accounted for by differences in fundamental abilities of trainees. Testing of fundamental abilities could help identify trainees who will require additional training to achieve desired performance objectives.

Adult↗
PubMed2005

The history of anatomy and surgery of the preperitoneal space.

Preperitoneal (properitoneal) space is the space between the peritoneum and transversalis fascia. Bogros (1786-1825) described a triangular space in the iliac region between the iliac fascia, transversalis fascia, and parietal peritoneum. In the modern concept, this space lies between the peritoneum and posterior lamina of the transversalis fascia. In 1858, Retzius described the homonymous space, situated anterior and lateral to the urinary bladder (prevesical space). In 1975, Fowler reported that the preperitoneal fascia of the groin is distinct from the transversalis fascia. Preperitoneal herniorrhaphy may be subdivided into 2 approaches: transperitoneal and inguinal. We present herein the evolution of approaches to the preperitoneal space from use of the transperitoneal (or posterior) to use of the anterior preperitoneal and posterior preperitoneal approaches. As anatomic knowledge has increased, the evolution of laparoscopic surgery has paralleled that of open procedures.

Fascia↗
PubMed2005

Video-assisted surgery represents more than a loss of three-dimensional vision.

BACKGROUND: Loss of depth cues is a major challenge facing surgeons performing video-assisted surgery (VAS). Whether the degradation of image quality from a video-displayed image plays a direct role in performance of VAS has not been studied. METHODS: Twenty-four volunteer novice subjects were randomized to binocular direct-vision (BDV), monocular direct-vision (MDV), or video-imaging (VI) conditions. Each subject completed ten trials of a simple cutting task in a box trainer using standard laparoscopic instruments. RESULTS: VI subjects made significantly fewer correct incisions than both of the other groups for all trials. Differences between the BDV and MDV groups did not reach statistical significance. Improvement in performance was more rapid in the BDV group than in either the MDV or VI groups. CONCLUSIONS: The degradation of image quality with VI has a detrimental influence on VAS performance above and beyond the loss of binocular vision.

Adult↗
PubMed2005

When fundoplication fails: redo?

OBJECTIVE: The largest series in the literature dealing with redo fundoplication was presented and published in 1999 and included 100 patients. Herein we update this initial series of 100, with 207 additional patients who have undergone redo fundoplication (n = 307). SUMMARY BACKGROUND DATA: Increasing numbers of patients are failing esophagogastric fundoplication and requiring redo procedures. Data regarding the nature of these failures have been scant. METHODS: Data on all patients undergoing foregut surgery are collected prospectively. Between 1991 and 2004, 307 patients underwent redo fundoplication for the management of anatomic complications or recurrent GERD. Statistical analysis was performed with multiple chi2 and Mann-Whitney U analyses, as well as ANOVA. RESULTS: Between 1991 and 2004, 1892 patients underwent primary fundoplication for GERD (1734) or paraesophageal hernia (158). Of these, 54 required redo fundoplication (2.8%). The majority of failures (73%) were managed within 2 years of the initial operation (P = 0.0001). The mechanism of failure was transdiaphragmatic wrap herniation in 33 of 54 (61%). In the 231 patients who underwent fundoplication elsewhere, 109 had transdiaphragmatic herniation (47%, P = NS). In this group of 285 patients, 22 (8%) required another redo (P = NS). The majority of the procedures were initiated laparoscopically (240/307, 78%), with 20 converted (8%). Overall mortality was 0.3%. CONCLUSIONS: Failure of fundoplication is unusual in experienced hands. Most are managed within 2 years of the initial operation. Wrap herniation has now become the most common mechanism of failure requiring redo. Redo fundoplication was successful in 93% of patients, and most could be safely handled laparoscopically.

Fundoplication↗
PubMed2005

Real-time objective assessment of knot quality with a portable tensiometer is superior to execution time for assessment of laparoscopic knot-tying performance.

OBJECTIVE: Laparoscopic intracorporeal knot tying is a difficult skill to acquire. Currently, time to complete a knot is the most commonly used metric to assess the acquisition of this skill; however, without a measure of knot quality, time is a poor indicator of skills mastery. Others have shown that knot quality can be accurately assessed with a tensiometer, but obtaining this type of assessment has typically been cumbersome. We investigated a new method of real-time assessment of knot quality that allows for more practical use of knot quality as a performance metric. METHODS: Eleven experienced endoscopic surgeons tied 100 intracorporeal knots in a standard box trainer. Each of the knots was immediately tested using the InSpec 2200 benchtop tensiometer (INSTRON, Canton MA) where a knot quality score (KQS) is generated based on the load handling properties of the knotted suture. The execution time was also recorded for each knot. RESULTS: The assessment of all knots ended with one of two end points: knots that slipped (n=48) or knots that held until the suture broke (n=52). Knots that slip are generally of poorer quality than those that held. Execution time did not correlate with knot-quality score (r=0.009, P=.9), and the mean execution time did not differ significantly between slipped and held knots (65 vs 68 seconds, P=.8). No completion time criteria were able to accurately predict slipped versus held knots. The mean KQS difference between held and slipped knots was highly significant (24 vs 12, P<.0001). A knot with a KQS exceeding 20 was nearly 10 times more likely to hold than slip. CONCLUSION: Time to complete a knot is a poor metric for the objective assessment of intracorporeal knot-tying performance in the absence of a measure of knot quality. Real-time evaluation of the knot quality can accurately distinguish well-tied knots from poorly tied knots. This mode of assessment should be incorporated into training curriculum for surgical knot tying.

Biomechanical Phenomena↗
PubMed2005

Evaluation of a tensiometer to provide objective feedback in knot-tying performance.

Training and assessment methods for knot tying by medical students or residents have traditionally been subjective. Objective methods for evaluating creation of a tied knot should include assessing the strength and quality of the knotted suture. The purpose of this study was to evaluate the use of a tensiometer as a feedback device for improving knot-tying performance. Twelve medical students with no knot-tying experience were selected to perform three-throw instrument ties with 00 silk suture. Students were randomly assigned to perform between 10 and 20 baseline knots and then received one of four feedback training conditions followed by 10 completion knots. Subjects were timed, and all knots were pulled in the tensiometer to assess for strength and slippage. Differences between baseline and completed knots for each subject were analyzed with an unpaired t test. Subjects receiving both subjective and tensiometer feedback demonstrated the greatest improvements in knot quality score (KQS) and slip percentage (Subject 1: 0.15 +/- 0.9 vs 0.21 +/- 0.05, P < 0.04, 75% vs 60%, P = NS; Subject 2: 0.22 +/- 0.10 vs 0.29 +/- 0.05, P < 0.02, 33% vs 0%, P < 0.05; Subject 3: 0.10 +/- 0.07 vs 0.25 +/- 0.07, P < 0.0001, 60% vs 10%, P < 0.01). Objective assessment of knot-tying performance is possible using the tensiometer device. Introduction of the tensiometer during the learning phase produced improved KQS and slip percentage in most students regardless of the number of baseline knots tied. Greatest improvements in performance were seen when the tensiometer was used in combination with subjective instruction.

Adult↗
PubMed2004

Laparoscopic approach reduces likelihood of perioperative complications in patients undergoing adrenalectomy.

Laparoscopy has been reported advantageous over the conventional open technique for adrenalectomy. However, most comparative series include the relatively more challenging cases in the open group. The aim of this study is to assess the actual role of laparoscopy in reducing perioperative complications compared to open surgery in patients undergoing adrenalectomy. Between January 1992 and December 2002, we performed 148 adrenalectomies in 138 patients. Depending on the approach, patients were divided into laparoscopic (LA) or open adrenalectomy (OA) groups. Demographics, tumor characteristics, operative data, and outcomes were analyzed. Linear and logistic regressions identified factors influencing perioperative outcomes. Multivariate-adjusted logistic regression assessed independent relationship between factors and perioperative outcomes. A total of 78 cases were performed laparoscopically and 70 open. Patients were matched for age and sex. Tumor size was smaller (3 +/- 2 vs 5 +/- 3 cm), operative time was shorter (133 +/- 65 vs 165 +/- 100 min), estimated blood loss was less (114 +/- 152 vs 350 +/- 417 cc), length of stay was shorter (3 +/- 2 vs 7 +/- 3 days), and overall complication rate was lower (7% vs 20%) in the LA compared to the OA group. The incidence of cancer in tumors > or = 6 cm (31%) was higher than in those < 6 cm (4%). All patients with cancer underwent OA. LA was the only factor independently associated with a decreased likelihood of intraoperative bleeding and postoperative pulmonary complications. Large and malignant adrenal tumors are more frequently removed through an open approach. However, this fact has no influence on the advantages of the LA over the OA. Laparoscopy reduces perioperative adrenalectomy perioperative complication rates. It has a positive impact on intraoperative bleeding and postoperative pulmonary complications.

Adrenal Gland Diseases↗
PubMed2003

Objective psychomotor skills assessment of experienced and novice flexible endoscopists with a virtual reality simulator.

The objective of this study was to determine whether the GI Mentor II virtual reality simulator can distinguish the psychomotor skills of intermediately experienced endoscopists from those of novices, and do so with a high level of consistency and reliability. A total of five intermediate and nine novice endoscopists were evaluated using the EndoBubble abstract psychomotor task. Each subject performed three repetitions of the task. Performance and error data were recorded for each trial. The intermediate group performed better than the novice group in each trial. The differences were significant in trial 1 for balloons popped (P=.001), completion time (P=.04), and errors (P=.03). Trial 2 showed significance only for balloons popped (P=.002). Trial 3 showed significance for balloons popped (P=.004) and errors (P=.008). The novice group showed significant improvement between trials 1 and 3 (P<0.05). No improvement was noted in the intermediate group. Measures of consistency and reliability were greater than 0.8 in both groups with the exception of novice completion time where test-retest reliability was 0.74. The GI Mentor II simulator can distinguish between novice and intermediate endoscopists. The simulator assesses skills with levels of consistency and reliability required for high-stakes assessment.

Adult↗