Visuospatial ability correlates with performance in simulated gynecological laparoscopy.

OBJECTIVE: To analyze the relationship between visuospatial ability and simulated laparoscopy performed by consultants in obstetrics and gynecology (OBGYN). STUDY DESIGN: This was a prospective cohort study carried out at two community hospitals in Sweden. Thirteen consultants in obstetrics and gynecology were included. They had previously independently performed 10-100 advanced laparoscopies. Participants were tested for visuospatial ability by the Mental Rotations Test version A (MRT-A). After a familiarization session and standardized instruction, all participants subsequently conducted three consecutive virtual tubal occlusions followed by three virtual salpingectomies. Performance in the simulator was measured by Total Time, Score and Ovarian Diathermy Damage. Linear regression was used to analyze the relationship between visuospatial ability and simulated laparoscopic performance. The learning curves in the simulator were assessed in order to interpret the relationship with the visuospatial ability. RESULTS: Visuospatial ability correlated with Total Time (r=-0.62; p=0.03) and Score (r=0.57; p=0.05) in the medium level of the virtual tubal occlusion. In the technically more advanced virtual salpingectomy the visuospatial ability correlated with Total Time (r=-0.64; p=0.02), Ovarian Diathermy Damage (r=-0.65; p=0.02) and with overall Score (r=0.64; p=0.02). CONCLUSIONS: Visuospatial ability appears to be related to the performance of gynecological laparoscopic procedures in a simulator. Testing visuospatial ability might be helpful when designing individual training programs.

Glutathione and amino acid concentrations in human liver during short warm ischaemia and reperfusion: a pilot study.

Glutathione is a major antioxidant, and, in the present study, we investigated whether a clinical model of short warm ischaemia and reperfusion of the human liver during surgery would influence glutathione and amino acid metabolism. Previous studies in humans have demonstrated that ischaemia and reperfusion in skeletal muscle for up to 120 min have no major effect on muscle glutathione concentrations. Liver ischaemia and reperfusion in animals have demonstrated diverging results concerning glutathione metabolism. In the present study, six patients with liver malignancies, undergoing liver resection during warm ischaemia, were included. Liver biopsies were obtained from healthy appearing liver tissue from both lobes before ischaemia and at maximal ischaemia, and from the remaining liver lobe after 5, 10, 15, 20, 25 and 30 min of reperfusion. The biopsies were analysed for glutathione, amino acids and lactate. Median ischaemia time was 28 (range, 15-36) min. Lactate increased 266% at maximal ischaemia (P<0.05). No alterations in glutathione concentrations or the redox status of glutathione (GSH/total glutathione) were observed. Glutamate decreased 22% (P<0.05) at maximal ischaemia and increased thereafter 72% at 30 min of reperfusion (P<0.05). Alanine increased 105% at maximal ischaemia (P<0.05) and was normalized during reperfusion. BCAAs (branched-chain amino acids) increased 67% at maximal ischaemia (P<0.05). In conclusion, short-time ischaemia and reperfusion in the human liver did not affect glutathione concentrations, whereas changes were observed in amino acid concentrations during both ischaemia and reperfusion.

Knee replacement surgery as a human clinical model of the effects of ischaemia/reperfusion upon skeletal muscle.

The temporal pattern of metabolic alterations in muscle tissue during total ischaemia and reperfusion are not well-characterized in humans with respect to glutathione, amino acids and energy-rich compounds. In the present study, knee replacement surgery was used as a clinical model to elucidate this pattern of metabolic alterations. Patients (n=15) undergoing elective knee replacement surgery employing tourniquet ischaemia were studied. Muscle biopsies were taken from the quadriceps femoris muscle on the operated side preoperatively, at maximal ischaemia and after 24 h of reperfusion. The biopsies were analysed for glutathione, amino acids and energy-rich compounds. In addition the patients were randomized to receive either glucose or a mannitol infusion in the 24 h following tourniquet ischaemia. During ischaemia, muscle lactate increased by 400% (P<0.05) and phosphocreatine decreased by 70% (P<0.05). During the subsequent 24 h of reperfusion, muscle-reduced glutathione and total glutathione decreased by 27% and 22% (P<0.05) respectively. The muscle amino acid pattern changed during ischaemia with an increase in alanine by 65% (P<0.001) and a decrease in glutamate by 29% (P<0.001). During the reperfusion part of the study, no differences attributable to the infusion of mannitol or glucose were observed. During tourniquet ischaemia and subsequent reperfusion, changes in glutathione metabolism developed, indicating oxidative stress. Knee replacement surgery as a clinical model was useful during the ischaemia period, whereas the reperfusion period was dominated by the general changes seen postoperatively.

Visuospatial abilities correlate with performance of senior endoscopy specialist in simulated colonoscopy.

Visuospatial abilities have been demonstrated to predict the performance of medical students in simulated endoscopy. However, little has been reported whether differences in visuospatial abilities influence the performance of senior endoscopists or whether their vast endoscopy experience reduces the importance of these abilities. Eleven senior endoscopists were included in our study. Before the simulated endoscopies in GI Mentor II (gastroscopy: case 3, module 1 and colonoscopy: case 3, module 1), the endoscopists performed three visuospatial tests: (1) pictorial surface orientation (PicSOr), (2) card rotation, and (3) cube comparison tests that monitor the ability of the tested person to re-create a three-dimensional image from a two-dimensional presentation as well as mentally manipulate that re-created image. The results of the visuospatial tests were correlated to the performance parameters of the virtual-reality endoscopy simulator. The percent of time spent with clear view in the simulated colonoscopy correlated well with the performance in the visuospatial PicSOr (r = -0.75, P = 0.01), card rotation (r = 0.75, P = 0.01), and cube comparison (r = 0.79, P = 0.004) tests. The endoscopists who performed better in the visuospatial tests also were better at maintaining visualization of the colon lumen. Those who performed better in the PicSOr test formed fewer loops during colonoscopy (r = 0.60, P = 0.05). In the technically less demanding simulated gastroscopy, there were no such correlations. The visuospatial tests performed better in endoscopists not playing computer games. Good visuospatial ability correlates significantly with the performance of experienced endoscopists in a technically demanding simulated colonoscopy, but not in the less demanding simulated gastroscopy.

Synthesis rates of total liver protein and albumin are both increased in patients with an acute inflammatory response.

The general perception that catabolism and inflammation are associated with a high synthesis rate of total liver protein and a low albumin synthesis rate has been challenged in recent years by several studies in man, indicating that the synthesis rate of albumin in response to a catabolic insult is increased rather than decreased. Thus changes in liver protein synthesis rates in conjunction with catabolism and acute inflammation in man need to be characterized better. The aim of the present study was to measure protein synthesis rates of total liver protein and albumin during a state of acute inflammation. Patients (n = 10) undergoing acute laparoscopic cholecystectomy due to acute cholecystitis were investigated. FSRs (fractional synthesis rates) of total liver protein (liver biopsy specimens) and albumin (plasma samples) were investigated as early as possible during the surgical procedure, using a flooding dose of L-[2H5]phenylalanine. The results were compared with a reference group of patients without cholecystitis undergoing elective laparoscopic cholecystectomy (n = 17). FSR of total liver protein was 60% higher (P < 0.001) and the FSR of albumin was 45% higher (P < 0.01) in the cholecystitis patients compared with the control group. In conclusion, the synthesis rates of total liver protein and albumin are both increased in patients with an acute general inflammatory reaction undergoing laparoscopic cholecystectomy.

Effects on skeletal muscle glutathione status of ischemia and reperfusion following abdominal aortic aneurysm surgery.

Glutathione (GSH) is an important endogenous scavenger against reactive oxygen species. Elective abdominal surgery without ischemia and reperfusion leads to decreased muscle GSH concentrations 4-72 hr postoperatively without altering GSH redox status. In the present study, we investigated to what extent muscle GSH status was affected during and following elective abdominal aortic aneurysm repair. From patients (n = 10) undergoing abdominal aortic repair, thigh muscle specimens were taken preoperatively, at maximal ischemia, and at 10 min and 4, 24, and 48 hr of reperfusion. Specimens were analyzed for GSH, amino acids, and energy-rich compounds. At maximal ischemia, phosphocreatine decreased by 37% (p < 0.05) and lactate and creatine increased by 274% and 57% (p < 0.001 and 0.05), respectively, indicating ischemia during the clamping of aorta. Adenosine triphosphate, on the other hand, remained unaltered during the entire study period. Total GSH (tGSH) decreased by 46% at 24 hr and by 43% at 48 hr of reperfusion (p < 0.001), while reduced GSH decreased by 48% at 24 hr and by 44% at 48 hr (p < 0.001). The redox status (GSH/tGSH) of GSH and oxidized GSH remained unaltered. Among the constituent amino acids of GSH, glycine and cysteine remained unaltered while glutamine and glutamate decreased by 55% and 55%, respectively (p < 0.001). Abdominal aortic aneurysm repair induces metabolic alterations characteristic for ischemia. The antioxidative capacity in terms of muscle levels of GSH was decreased. However, the oxidative stress during reperfusion did not change GSH status more than what has been reported following abdominal surgery without ischemia and reperfusion. The results indicate that the oxidative stress elicited by elective abdominal aortic aneurysm repair is outbalanced by a compensated GSH metabolism not giving rise to an increased amount of oxidized GSH or an altered GSH redox status.

Tension-free inguinal hernia repair: TEP versus mesh-plug versus Lichtenstein: a prospective randomized controlled trial.

OBJECTIVE: To compare laparoscopic hernioplasty with two open tension-free hernia repairs. SUMMARY BACKGROUND DATA: Laparoscopic hernioplasty is associated with a short rehabilitation, but it is a technically difficult procedure. It is unclear if it has advantages over the technically easier open tension-free herniorrhaphy. METHODS: Two hundred ninety-nine men 30 to 75 years old were randomized to undergo laparoscopic totally extraperitoneal hernioplasty (TEP), open operation with mesh-plug and patch, or Lichtenstein's operation. RESULTS: Two hundred ninety-four (98%) patients were followed for 19.8 +/- 8.6 months. Over 90% of the patients in all groups were operated in day surgery; the rest of the patients were all discharged within 24 hours. Postoperative pain (visual analog score) was lower in the patients undergoing TEP than in those undergoing Lichtenstein and mesh-plug procedures. The median sick-leave period was 5 days in the TEP group, 7 days in the mesh-plug group, and 7 days in the Lichtenstein group. The median time to full recovery was significantly shorter in the TEP group compared to the other two groups. There were no major complications. Two recurrences were found in the TEP group and two in the mesh-plug group. CONCLUSIONS: Laparoscopic hernioplasty is superior to tension-free open herniorrhaphy in terms of postoperative pain and rehabilitation.