Ormond N.M. Panton

Correlating motor performance with surgical error in laparoscopic cholecystectomy

BackgroundAnalysis of motor performance in minimally invasive surgery (MIS) is a new field with applications in surgical training, surgical simulators, and robotics. Force/torque and derivatives of tool tip position (velocity, acceleration, and jerk) are examples of measures of motor performance (MMPs). Few studies have measured MMPs or have correlated MMPs with surgical performance during MIS on humans. The objectives of this study were to determine the feasibility of a novel multimodal system to quantify MMPs in laparoscopic cholecystectomy and to attempt to correlate MMPs with the magnitude of error as a measure of surgical performance.MethodsNovice and expert surgeons performed laparoscopic cholecystectomies in two groups of three patients each. MMPs were obtained using a combination of optical and electromagnetic tool tip tracking and a force/torque sensor on a modified Maryland dissector. Error scores for laparoscopic cholecystectomy were calculated using a previously validated system. Novice and expert measurements were compared, and correlations were made between error scores and MMPs.ResultsError scores were similar between novices and experts. Novice surgeons had a significantly greater mean velocity (566 ± 83 vs 85 ± 32 mm/s, p = 0.006) and acceleration (2,600 ± 760 vs 440 ± 174 mm/s2, p = 0.050) compared to expert surgeons. Force (16.5 ± 4.6 vs 18.3 ± 6.0 N, p = 0.829), position (121 ± 25 vs 135 ± 72 mm, p = 0.863), and jerk (19,600 ± 7,410 vs 2,430 ± 367 mm/s3, p = 0.138) were similar between groups. A positive correlation was found in novice surgeons between error score and jerk (Pearson correlation, 0.999; p = 0.035).ConclusionsIt is feasible to quantify MMPs in laparoscopic cholecystectomy. Novice and expert surgeons can be differentiated by MMPs; moreover, there may be a positive correlation between jerk and error score in novice surgeons.

Mechanical preparation of the large bowel for elective surgery: Comparison of whole-gut lavage with the conventional enema and purgative technique

In this prospective, randomized study, 121 elective colorectal surgery patients had whole-gut lavage (n = 67) or enemas and purgatives (n = 54). Patient characteristics were well matched. Intravenous metronidazole and tobramycin were administered preoperatively initially in 53 patients, with the remaining 68 patients receiving the drugs perioperatively. Bowel preparation was satisfactory (minimal or no contents remaining) in 92.8 percent of patients with whole-gut lavage and 92.6 percent with enemas and purgatives (p = 0.72). Nasogastric tube insertion was poorly tolerated by 39 percent of the patients receiving whole-gut lavage, and enema tube insertion by 23 percent with enemas and purgatives. Fluid infusion tolerance was similar with both techniques. Abdominal wound sepsis occurred in 22 patients (18.8 percent), being unrelated to mechanical preparation or antimicrobial prophylaxis (p = 0.19). Colostomy closure was associated with a 42.8 percent sepsis rate. Excluding this group, wound sepsis with the remaining procedures was 13 percent (statistically significant, p = 0.03). Other complications included intraabdominal abscesses (3.3 percent), anastomotic leaks (2.5 percent), eviscerations (1.6 percent), and an operative mortality of 1.6 percent. We have concluded that whole-gut lavage and enemas and purgatives are equally efficacious mechanically with similar associated wound sepsis rates.

Operative length independently affected by surgical team size: data from 2 Canadian hospitals

BACKGROUND Knowledge of the composition of a surgical team is the premise for studying efficiency inside the operating room. METHODS To investigate the team composition in general surgery procedures, we retrospectively reviewed procedures performed by an expert general surgeon in 2007-08 at 2 tertiary hospitals. For each patient, demographic characteristics, procedure type, team members and procedure length were extracted from intraoperative nursing records. We assessed procedure complexity using a calculated index. Multiple logistic regressions were performed to assess the association between procedure length and team size after adjusting for procedure complexity and patient condition. RESULTS For the 587 procedures reviewed, the mean procedure length was 88 (standard deviation [SD] 51) minutes. On average, 8 team members (range 4-14), including surgeons, anesthesiologists, nurses and other specialists, were involved in each procedure. Only 47 (8%) procedures were performed by 1 surgeon. Most were performed by 2 (295 [50%]) or 3 surgeons (214 [36%]). Half the team members were nurses (mean 4, range 1-7). Both the complexity of the operation and the team size affected the procedure length significantly. When procedure complexity and patient condition were constant, adding 1 team member predicted a 7-minute increase in procedure length. CONCLUSION This study demonstrates that a frequent change of core team members has a negative impact on surgical performance. Management strategies need to improve to optimize team efficiency in the operating room.

Objective Assessment of Laparoscopic Skills Dual-Task Approach

Background. Assessment of surgical performance is often accomplished with traditional methods that often provide only subjective data. Trainees who perform well on a simulator in a controlled environment may not perform well in a real operating room environment with distractions. This project uses the ideas of dual-task methodology and applies them to the assessment of performance of laparoscopic surgical skills. The level of performance on distracting secondary tasks while trying to perform a primary task becomes an indirect but objective measure of the surgical skill of the trainee. Methods. Nine surgery residents and 6 experienced laparoscopic surgeons performed 3 primary tasks on a laparoscopic virtual reality simulator (camera position, grasping, and cholecystectomy) while being distracted by 3 secondary tasks (counting beeps, selective responses, and mental arithmetic). Completion time and error rates were recorded for each combination of tasks. Results. When performed separately, time to completion and error rates for primary and secondary tasks were similar for learners and experts. When performing the tasks simultaneously, learners had more errors than experts. Error rates increased for learners when distracting tasks became more difficult or required more attention. Expert surgeons maintained consistent error rates despite the increasing difficulty of task combinations. Conclusions. The use of dual-task methodology may help trainers to identify which surgical trainees require more preparation before entering the real operating room environment. Expert surgeons are capable of maintaining performance levels on a primary task in the face of distractions that may occur in the operating room.

Gastrointestinal tuberculosis: The great mimic still at large

Gastrointestinal tuberculosis has declined markedly in frequency since the introduction of antituberculous therapy. As a result, the diagnosis is often delayed in North American patients. Segmental colonic disease, especially in the absence of pulmonary tuberculosis, is often difficult to differentiate from Crohns disease or a neoplasm. We describe a case of colonic tuberculosis mimicking carcinoma of the hepatic flexure of the colon.

Laparoscopic management of gastrointestinal stromal tumours: review at a Canadian centre

BACKGROUND Laparoscopic wedge resection has been widely accepted for small benign gastric tumours. Large gastrointestinal stromal tumours (GISTs), however, can be difficult to manipulate laparoscopically and are at risk for capsule disruption, which can then result in peritoneal seeding. Some authors have suggested that large GISTs (> 8 cm) are best approached using an open technique. However, there has been no consensus as to what the cut-off size should be. We conducted one of the largest Canadian series to date to assess outcomes and follow-up of the laparoscopic management of GISTs. METHODS All patients with gastric GISTs presenting to Vancouver General Hospital and University of British Columbia Hospital between 2000 and 2008 were reviewed. Most lesions were resected using a wedge technique with closure of the stomach facilitated by an endoscopic linear stapling device. RESULTS In all, 23 patients presented with GISTs; 19 patients underwent laparoscopic resection and, of these, 15 had a purely laparoscopic operation and 4 had a hand-assisted laparoscopic resection. Mean tumour size was 3.2 cm, with the largest tumour measuring 6.8 cm. There were no episodes of tumour rupture or spillage and no major intraoperative complications. All margins were negative. Mean follow-up was 13.3 (range 1-78) months. There was no evidence of recurrence or metastasis. CONCLUSION The laparoscopic management of gastric GISTs is safe and effective with short hospital stays and good results over a mean follow-up of 13.3 months. We believe that it should be the preferred technique offered to patients.

Fluorescent cholangiography in laparoscopic cholecystectomy: the initial Canadian experience

BACKGROUND Bile duct injury remains a worrisome complication of laparoscopic cholecystectomy. Indocyanine Green (ICG) fluorescent cholangiography (FC) is a new approach that facilitates real-time intraoperative identification of biliary anatomy. This technology is hoped to improve the safety of dissection within Calots triangle. METHOD Demographics, intraoperative details, and subjective surgeon data were recorded for elective cholecystectomy cases involving ICG. Goals were to identify rates of bile duct identification, and assess the perceived benefit of the device. RESULTS ICG was used in 12 biliary cases in Canada. Visualization rates of the cystic and common bile ducts were 100% and 83%, respectively. Also, 83% of surgeons felt that FC incorporated smoothly into the operation. No complications have been related to the technology. CONCLUSIONS FC allows noninvasive real-time visualization of the extrahepatic biliary tree. This novel technique has received positive feedback in its initial Canadian use and will likely be a durable adjunct for minimally invasive surgery.