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J Jakimowicz

Publications and source records attributed to J Jakimowicz.

16 recordsLinked to original sources
PubMed2003

The learning curve on the Xitact LS 500 laparoscopy simulator: profiles of performance.

BACKGROUND: This study assesses the acquisition of skill and the learning curve associated with the performance of the clip-and-cut task on the Xitact LS 500 virtual reality (VR) simulator in laparoscopic cholecystectomy. METHODS: A group of 33 residents and interns with no previous laparoscopic experience participated in the study. All participants received a 1-h familiarization tour on the simulator. Thirty participants completed a full course of 30 simulation runs over 3 days (10 runs per day). The outcome parameters were a previously validated sum-score and time to complete performance. RESULTS: Group demographics were similar. Of the participants who completed the full study, 16.7% appeared to have such a high level of innate psychomotor abilities that they were considered proficient in the task immediately after the initial familiarization tour. Most participants (63.3%) had a moderate level of innate abilities, and their performance improved through repetitive VR training. In our study, 20% of the participants had such a low level of innate abilities that they were unable to achieve an acceptable performance in our minimal-access surgery (MAS) simulation. CONCLUSIONS: Learning curves cannot be assessed by examining the repetitive training of only one person. There seem to be four different performance profiles, reflecting the fact that some people are more adept than others to be trained by MAS procedural VR simulation. For participants receptive to training--63.3% in this study--proficiency in the task occurs after approximately 25 simulative runs.

Adult↗
PubMed2003

The intercollegiate Basic Surgical Skills Course.

OBJECTIVE: This study was undertaken to establish residents' progress in minimal access surgery (MAS) after attending the Intercollegiate Basic Surgical Skills Course (BSSC) by means of the Xitact LS500 laparoscopy simulator assessment program. METHODS: Twenty-five surgical residents attended the BSSC in Leiden and Eindhoven, The Netherlands. Before and after the course, participants performed three "runs" on the Xitact LS500, featuring a standardized laparoscopic cholecystectomy clip-and-cut task. A control group of 25 interns not attending the course also performed two sessions of three runs. Parameters of interest were "score" and "time for completion of task". RESULTS: No significant differences were found within the resident group for the parameters "time" and "score" when comparing outcomes pre- and post-BSSC. No significant differences were found comparing time and score between residents and interns on each of the six runs, except for time in run 2. Over six runs, both residents and interns became significantly faster. CONCLUSIONS: The Xitact LS500 cholecystectomy simulator did not detect significant improvement in MAS performance among a group of surgical residents attending the BSSC.

Adult↗
PubMed2003

Construct validity: experts and novices performing on the Xitact LS500 laparoscopy simulator.

BACKGROUND: This study was undertaken to establish construct validity of the Xitact LS500, a virtual reality laparoscopic cholecystectomy simulator. The primary research statement is: "The clip-and-cut task on the Xitact LS500 virtual reality laparoscopic cholecystectomy simulator mimics the surgical procedure of the clipping and cutting of the cystic duct and artery during the laparoscopic cholecystectomy adequately." METHODS: According to the level of experience of the surgeon, an "expert group opinion" was formed resulting from 37 surgeons having performed over 100 laparoscopic cholecystectomies, and a "novice group opinion" was formed resulting of 37 surgeons having no experience at all with performing laparoscopic cholecystectomy. Participants received an instructed hands-on "tour" on the Xitact simulator and performed three formal simulation runs. RESULTS: The "novice group" is younger and more surgeons are female. Performance scores in the "expert" group are significantly higher on the second (p value 0.011) and third (p value 0.005) run, compared to the novices' scores. Experts are significantly faster on completion of all three runs. There is an increase in score over runs in both groups, which is statistically significant in the "expert group." Less than one-third of surgeons in either group are able to correctly predict their performance score as generated by Xitact. Both "experts" and "novices" feel it is useful to train with Xitact LS500 in the surgical curriculum. CONCLUSIONS: Three hypotheses, formulated to operationalize the primary research statement, could be answered affirmatively. Although further validation studies are needed, the Xitact LS500 simulator seems to be able to discriminate between expert and novice surgeons in this research setting, and thus the construct for this setting is considered to be valid.

Adult↗
PubMed2002

Face-, expert, and referent validity of the Xitact LS500 laparoscopy simulator.

BACKGROUND: This study was undertaken to establish face-, expert, and referent validity of the Xitact LS500; a virtual reality laparoscopic cholecystectomy simulator. METHODS: A four-page, 20-item structured questionnaire was presented to 120 surgeons attending a surgical convention. Participants received an instructed hands-on "tour" on the Xitact simulator. Data were analyzed according to the level of experience of the surgeon, resulting in an "expert group opinion" of 87 surgeons and a "referent group opinion" of 33 surgeons. RESULTS: The majority of respondents believe Xitact has the potential to become a useful tool in teaching (93.1%) and measuring performance assessment (79.3%) in laparoscopic cholecystectomy. Expert- and referent-group opinion does not differ significantly on any of the presented statements. The opinion regarding the realism of the virtual laparoscopic cholecystectomy environment is favorable among both groups, although it is considered not yet perfect. The "haptic feedback" sensation of the Xitact is a parameter that needs further development. CONCLUSIONS: Both expert- and referent surgeons value Xitact to be an important and useful tool in the laparoscopic teaching setting. Further studies need to be performed to establish the construct validity of the simulator (e.g., to what extent is the simulator logically encompassed into a theoretical framework of acquiring skills, needed for the laparoscopic cholecystectomy) to measure shortening of learning curves on the laparoscopic cholecystectomy procedure, and ultimately to justify its use in the surgical curriculum.

Adult↗
PubMed2002

The Advanced Dundee Endoscopic Psychomotor Tester (ADEPT) objectifying subjective psychomotor test performance.

BACKGROUND: This study was undertaken to establish the value of the Advanced Dundee Psychomotor Tester (ADEPT) as an objective real-time scoring system, correcting for subjective assessor opinion on endoscopic task performance. The main research questions were as follows: Are surgeons good estimators of their own performance on ADEPT? Do surgeons perceive ADEPT to be a valid instrument for measuring laparoscopic skills? Does performance on ADEPT reflect innate psychomotor ability? METHODS: Each of 45 surgeons completed two runs on ADEPT. The runs comprised five standardized tasks. A posttest visual analog scaled (VAS) questionnaire measuring attitude toward skills testing in general, validation, and performance on ADEPT was used. Subjective responses were compared with objective scores generated through performance on ADEPT. RESULTS: Surgeons emphasize the importance of using a variety of training methods for surgical residents during their residency, including laparoscopic virtual reality simulators. Monitoring of residents' endoscopic progress seemed to be a key issue. Surgeons themselves underestimate their individual performance on ADEPT (mean subjective score of 6.1 vs mean objective score of 6.6). Self-reported performance on ADEPT is unreliable because confidence intervals between the VAS score and the ADEPT score overlap. Surgeons disagree on the validity of ADEPT. The mean score for validity was 5.8, ranging from 0 to 10 with almost equal distribution over the scale. Innate ability is established as surgeons' scores express high concordance between test run and true run, with 72.7% of the participants' true run score within one distance from the test run. CONCLUSIONS: Surgeons cannot correctly predict their standardized individual test result on ADEPT. Performance on ADEPT reflects innate psychomotor ability along with improvement over runs. Surgeons are ambivalent in assessing the validity of ADEPT, irrespective of personal performance.

Clinical Competence↗
PubMed2000

Hand-assisted laparoscopic surgery (HALS) with the HandPort system: initial experience with 68 patients.

OBJECTIVE: To evaluate the feasibility and potential benefits of hand-assisted laparoscopic surgery with the HandPort System, a new device. SUMMARY BACKGROUND DATA: In hand-assisted laparoscopic surgery, the surgeon inserts a hand into the abdomen while pneumoperitoneum is maintained. The hand assists laparoscopic instruments and is helpful in complex laparoscopic cases. METHODS: A prospective nonrandomized study was initiated with the participation of 10 laparoscopic surgical centers. Surgeons were free to test the device in any situation where they expected a potential advantage over conventional laparoscopy. RESULTS: Sixty-eight patients were entered in the study. Operations included colorectal procedures (sigmoidectomy, right colectomy, resection rectopexy), splenectomy for splenomegaly, living-related donor nephrectomy, gastric banding for morbid obesity, partial gastrectomy, and various other procedures. Mean incision size for the HandPort was 7.4 cm. Most surgeons (78%) preferred to insert their nondominant hand into the abdomen. Pneumoperitoneum was generally maintained at 14 mmHg, and only one patient required conversion to open surgery as a result of an unmanageable air leak. Hand fatigue during surgery was noted in 20.6%. CONCLUSIONS: The hand-assisted technique appeared to be useful in minimally invasive colorectal surgery, splenectomy for splenomegaly, living-related donor nephrectomy, and procedures considered too complex for a laparoscopic approach. This approach provides excellent means to explore, to retract safely, and to apply immediate hemostasis when needed. Although the data presented here reflect the authors' initial experience, they compare favorably with series of similar procedures performed purely laparoscopically.

Abdomen↗
PubMed1999

E.A.E.S. multicenter prospective randomized trial comparing two-stage vs single-stage management of patients with gallstone disease and ductal calculi.

BACKGROUND: The current management of patients with gallstone disease and ductal calculi consists of endoscopic stone extraction (ESE) followed by laparoscopic cholecystectomy (LC). Following the advent of techniques of laparoscopic ductal stone clearance, an alternative single-stage laparoscopic treatment was introduced for these patients. The European Association of Endoscopic Surgery (E.A. E.S.) set up a ductal stone trial to compare the relative efficacy and outcome of these two management options. METHODS: A prospective randomized controlled clinical trial compared two management options. Group A (n = 150) received preoperative endoscopic retrograde cholangiography (ERC) with ESE followed by LC during the same hospital admission, and group B (n = 150) received single-stage laparoscopic management. RESULTS: There were no significant differences between the two groups in the clinical demographic details and the pretreatment biochemical findings. In group A, 14 of 150 patients received single-stage treatment; in group B, 17 of 150 were managed by the two-stage approach (protocol violation = 31/300, 10%). In group A patients managed in accordance with randomization, ERC was successful in 129/136 (95%) and preoperative ESE succeeded in 82/98 (84%) with ductal calculi detected by the ERC. Two patients had malignancies and one refused surgery. Thus, 133 patients underwent surgery. Of this group, 116 had LC only and 17 had LC and attempted laparoscopic duct exploration. There were eight conversions to open surgery (6%), 17 complications for both stages (12.8%), and two postoperative deaths (1.5%). In group B patients managed in accordance with randomization, intraoperative cholangiography was successful in 132/133 (99%). Twenty-one (16%) had normal findings, ductal calculi were found in 109, and other pathology was noted in two (periampullary cancer, severe pancreatitis). These two patients and one other (who had gross adhesion in the triangle of Calot) were converted at the start of the procedure. Transcystic ductal stone clearance was successful in 45 of 56 patients (80%), and laparoscopic direct common duct (CBD) exploration was successful in 47 of 55 patients (85%). This group includes 53 patients who underwent primary direct exploration and two failed attempts at transcystic extraction. The conversion rate was 13%. Postoperative complications were encountered in 21 patients (15.8%), and one patient died of a major myocardial infarction (0. 75%). The one postoperative death and the 10/11 biliary complications occurred in the laparoscopic supraduodenal CBD exploration subgroup. The conversion rate was higher in group B (17 vs eight; p = 0.08). Laparotomy in the postoperative period was required in three patients in group A and four patients in group B. The group B patients were in hospital for 3 days less than patients who had two-stage management (median, 6.0, IQR = 4.25-12 vs median, 9.0, IQR = 5.5-14; p < 0.05). CONCLUSIONS: The results demonstrate equivalent success rates and patient morbidity for the two management options but a significantly shorter hospital stay with the single-stage laparoscopic treatment. The findings indicate that in fit patients (ASA I and II), single-stage laparoscopic treatment is the better option, and preoperative ESE should be confined to poor-risk patients-i.e., those with cholangitis or severe pancreatitis.

Adolescent↗
PubMed1998

Laparoscopic insufflation of the abdomen reduces portal venous flow.

BACKGROUND: The adverse effects of sustained elevated intraperitoneal pressure (IPP) on cardiovascular, pulmonary and renal systems have been well documented by several reported experimental and clinical studies. Alteration in the splanchnic circulation has also been reported in animal experiments, but details of the exact hemodynamic changes in the flow to solid intraabdominal organs brought on by a raised intraperitoneal pressure in the human are not available. The aim of the present study was to estimate effect of increased IPP on the portal venous flow, using duplex Doppler ultrasonography in patients undergoing laparoscopic cholecystectomy. METHODS: The studies were performed using the SSD 2000 Multiview Ultrasound Scanner and the UST 5536 7.0-MHz laparoscopic transducer probe. Details of the measurements were standardized in according to preset protocol. Statistical evaluation of the data was conducted by the two-way analysis of variance (ANOVA). RESULTS: The flow measurement data have demonstrated a significant (p < 0.001) decrease in the portal flow with increase in the intraperitoneal pressure. The mean portal flow fell from 990 +/- 100 ml/min to 568 +/- 81 ml/min (-37%) at an IPP of 7.0 mmHg and to 440 +/- 56 mmHg (-53%) when the IPP reached 14 mmHg. CONCLUSIONS: The increased intraperitoneal pressure necessary to perform laparoscopic operations reduces substantially the portal venous flow. The extent of the volume flow reduction is related to the level of intraperitoneal pressure. This reduction of flow may depress the hepatic reticular endothelial function (possibly enhancing tumor cell spread). In contrast, the reduced portal flow may enhance cryoablative effect during laparoscopic cryosurgery for metastatic liver disease by diminishing the heat sink effect. These findings suggest the need for a selective policy, low pressure or gas-less techniques to positive-pressure interventions, during laparoscopic surgery in accordance with the disease and the therapeutic intent.

Abdomen↗
PubMed1997

[Abdominal wall metastasis following surgical removal of colorectal carcinomas].

Abdominal wall metastases after laparoscopic resection of colorectal cancer have been reported by various authors. It appeared that abdominal wall metastases occur more frequently after laparoscopic than after conventional, open resection of colorectal cancer. However, the frequency of abdominal wall metastases after laparoscopic surgery varies from only 0 to 1.9% in centres with sufficient relevant experience, whereas after conventional resections the frequency is 0.8-3.3%. A randomized clinical study comparing laparoscopic with conventional resection of colon cancer is necessary to assess the optimal surgical approach to colon cancer. Such a trial has been set up.

Abdominal Muscles↗
PubMed1996

Hepatobiliary anatomy in patients with transposition of the gallbladder: implications for safe laparoscopic cholecystectomy.

The surgical anatomy of six patients with sinistroposition of the gallbladder is described. Five of these were encountered in a consecutive series of 1764 patients undergoing laparoscopic cholecystectomy for symptomatic gallstone disease in two hospitals between 1989 and 1994, a prevalence of 0.3 per cent in patients undergoing this operation. Despite the left-sided transposition of the gallbladder, the biliary pain experienced by these patients was always on the right side. Preoperative diagnosis of this anomaly was made in only one of six patients despite routine preoperative external ultrasonography and selective preoperative cholangiography. In sinistroposition the cystic artery always crosses in front of the common bile duct from right to left. The cystic duct may open on the left or right side of the common hepatic duct. The anomaly does not preclude safe laparoscopic cholecystectomy but modifications of the port sites and use of the falciform lift facilitate the procedure in these cases. The anatomical features of the sixth case encountered in a patient undergoing resection of hilar cholangiocarcinoma indicate that sinistroposition of the gallbladder may be due to failure of development of segment IV of the liver.

Adult↗
PubMed1996

EAES ductal stone study. Preliminary findings of multi-center prospective randomized trial comparing two-stage vs single-stage management.

BACKGROUND: The current management of patients with ductal calculi and gallstone disease consists of endoscopic stone extraction (ESE) followed by laparoscopic cholecystectomy (LC). The advent of techniques of laparoscopic ductal stone clearance has introduced an alternative single stage laparoscopic treatment for these patients. The EAES ductal stone trial was set up to compare the relative efficacy and outcome of these two management options. METHODS: The study consists of a prospective randomized controlled clinical trial comparing two management options of patients undergoing LC and suspected of harbouring common duct stones. Patients registered into the trial are randomized to one of two arms: (i) Group A-preoperative ERC with ESE followed by LC during the same hospital admission. (ii) Group B-single stage laparoscopic management consisting of LC and laparoscopic stone extraction either by the trans-cystic duct route or by direct supraduodenal common duct exploration. RESULTS: This preliminary analysis was carried out on 207 randomized patients with comparisons being made on the intention to treat principle. The two groups (A = 106, B = 101) were comparable with respect to clinical features. ASA grade, serum biochemistry and ultrasound findings. CONCLUSIONS: These preliminary findings indicate equivalent success rates and patient morbidity between the two management options but a shorter hospital stay (cost benefit) with the single stage laparoscopic treatment. Trans-cystic duct extraction is a more benign procedure than laparoscopic supraduodenal CBD exploration and is accompanied by a significantly shorter hospital stay. The higher incidence of conversion in the single stage laparoscopic group compared to the two-stage arm is due to the preference for open common duct exploration when the laparoscopic attempt failed by the majority of participating surgeons. The results to-date suggest that in fit patients, single stage laparoscopic treatment is the better option and the role of ESE should change to selective use in those patients in whom laparoscopic ductal stone extraction has failed.

Adolescent↗
PubMed1989

Early detection of stenosis of femoro-distal grafts. A surveillance study using colour-duplex scanning.

The development of stenoses following femoro-distal bypass procedures may jeopardise graft function. In a prospective study serial assessment of femoro-distal grafts in 77 patients was performed over a period of 13 months. Forty-eight of the bypasses were in situ, 18 were reversed veingrafts and 11 were modified sheep collagen grafts. Colour coded duplex scanning of all grafts was performed in addition to physical examination, ankle systolic pressure measurements and pulse volume recordings. Stenotic areas were detected in the graft in 16 cases and at the site of the proximal anastomosis in one case. In one graft a residual valve leaflet was found. In addition eleven arterio-venous communications were observed in in situ veingrafts and one aneurysmal degeneration in a collagen graft was noted. All stenoses were detected by colour duplex scanning and confirmed by arteriography or operative exploration. Only 38% of the stenoses over 50% was associated with recurrent symptoms or could be detected by diminished palpable pulses. Ankle blood-pressure measurements and pulse volume recordings indicated the presence of a stenosis over 50% in only 46% of the cases. Twelve of 13 patients with graft stenosis over 50% were revised by vein patch plasty with a good result in all cases. The primary and secondary two year cumulative patency rates of all in situ bypasses were 63% and 79% respectively. Close surveillance of femoro-distal grafts appears justified by this study. Colour duplex scanning was superior to systolic ankle pressure measurements and pulse volume recording in detecting the development of graft stenosis.

Aged↗