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C K Kum

Publications and source records attributed to C K Kum.

At least 19 recordsLinked to original sources
PubMed2001

Evaluation of a head-mounted display (HMD) in the performance of a simulated laparoscopic task.

BACKGROUND: Head-mounted display (HM) units are used in various industries, but they have been tried only recently in surgery. In this study, we evaluated whether a commercially available HMD would improve or impede a laparoscopic task-in this case, suturing. METHODS: Six participants performed a total of 120 laparoscopic suture knots in an experimental model. The Olympus FMD011 model with a two-dimensional image was used. The order of each task with or without the head display unit was random. The time to complete each knot was recorded, and the results were analyzed. RESULTS: The display unit prolonged the suturing times of the subjects by 10% (p < 0.04). CONCLUSIONS: In this experimental model, the HMD we utilized did not appear to improve laparoscopic suturing. More developments, such as improved depth perception and better resolution, may increase its usefulness for laparoscopic tasks.

Computer Simulation↗
PubMed2001

Randomized trial of needlescopic versus laparoscopic cholecystectomy.

BACKGROUND: Several studies have reported the feasibility of using 'needlescopic' instruments with a diameter less than 3 mm in minimally invasive surgery. This study reports a comparison of needlescopic cholecystectomy and laparoscopic cholecystectomy. METHODS: Seventy-five patients with symptomatic chronic cholelithiasis were randomized to needlescopic (n = 37) or laparoscopic (n = 38) cholecystectomy. RESULTS: The duration of surgery in the two groups was similar. Patients in the needlescopic group had less pain (mean visual analogue score 2.2 versus 3.6; P < 0.003) and had smaller scars (median length 17.0 versus 25.0 mm; P < 0.001). In addition, patients in the needlescopic group tended to require fewer intramuscular pethidine injections (P = 0.05). However, oral analgesic requirements in the two groups were similar. There were no complications in either group. CONCLUSION: Needlescopic cholecystectomy resulted in less postoperative pain and a smaller surgical scar than laparoscopic cholecystectomy in patients with chronic cholecystitis.

Cholecystectomy, Laparoscopic↗
PubMed2000

Risk factors related to operative mortality and morbidity in patients undergoing emergency gastrectomy.

BACKGROUND: Emergency gastric resection for complicated peptic ulcer and gastric cancer is a major challenge for general surgeons. This study aimed to evaluate the results of emergency gastrectomy and to examine the factors that predict the operative outcome. METHODS: A total of 82 consecutive patients who underwent emergency gastrectomy were studied. The following variables were assessed: pathology, mortality rate, morbidity, reasons for reoperation and factors related to the outcome. RESULTS: There were 64 men and 18 women with a median age of 62 (range 30-90) years. The indications were bleeding and perforated gastric or duodenal ulcers in 45 and 20 patients respectively, and bleeding and perforated gastric tumours in seven and ten patients respectively. The overall mortality rate was 17 per cent (n = 14). The complication rate was 63 per cent and 11 patients (13 per cent) required reoperation. By multivariate analysis, age greater than 65 years and blood haemoglobin level less than 10 g/dl on admission were predictive of complications after emergency gastrectomy. Postoperative pulmonary and cardiac complications and hypotension on admission were independent risk factors associated with operative death. CONCLUSION: Age more than 65 years, haemoglobin level less than 10 g/dl and hypotension on admission were associated with a poor outcome after emergency gastrectomy. The operative result was not affected by the underlying gastric pathology.

Adult↗
PubMed1999

Needlescopic or minisite cholecystectomy.

Needlescopic or minisite cholecystectomy is laparoscopic cholecystectomy done through tiny ports from 1.4 mm to 3 mm in size. This refinement of conventional laparoscopic cholecystectomy reduces further the invasiveness of the operation and gives an improved cosmetic effect. This series describes the result of 36 needlescopic cholecystectomies done between February 1996 and April 1997. Patients with acute cholecystitis were excluded. There were two conversions to conventional laparoscopic surgery and no conversions to open surgery. Thirty-four patients were successfully treated by this technique. Analgesic consumption and cosmetic result was superior compared to a previous published series of conventionally done cases in the same department.

Adult↗
PubMed1998

Colonoscopic evaluation of severe hematochezia in an Oriental population.

BACKGROUND AND STUDY AIMS: Hematochezia is a common clinical problem. When the bleeding is brisk and continuous it requires prompt hospital admission and careful diagnostic evaluation and management. Colonoscopy has become the first-line investigative modality in patients presenting with severe hematochezia in many centers, including ours. A retrospective review was carried out to evaluate the effectiveness of colonoscopy in determining the cause of severe hematochezia in our Oriental population. PATIENTS AND METHODS: One hundred and ninety patients with severe hematochezia underwent colonoscopy at the National University Hospital, Singapore, from 1 January 1988 to 31 December 1994. Their records were retrieved and the data analyzed for sex, age, presentation, concomitant medical conditions, prevalence of recent non-steroidal anti-inflammatory drugs ingestion, past history of hematochezia, investigations, subsequent interventions and outcome. RESULTS: Colonoscopy as the fist-line investigative modality identified the site and cause of hematochezia in 78% (148/190) of cases. The site of bleeding remained "obscure" even after additional investigations in 15% (29/190) of cases. The commonest cause of severe hematochezia in our Oriental population was diverticular disease (30%, 57/190) with right-sided diverticular bleeding constituting 44% (25/57) of these cases. Overall, bleeding stopped spontaneously in 81% (154/190) of cases. Surgery was performed in 16% (30/190) of cases. The mortality related to severe hematochezia in this series was 5% (9/190). CONCLUSIONS: The diagnostic efficiency of colonoscopy in defining the site and cause of severe hematochezia in the Oriental population is comparable to most Western series. The commonest cause of severe hematochezia in our population was diverticular disease.

Adolescent↗
PubMed1997

Early international results of laparoscopic gastrectomies.

BACKGROUND: The first totally laparoscopic Billroth II gastrectomy was performed in 1992. To date, laparoscopic gastrectomy has been performed by a small number of surgeons around the world and the laparoscopic approach has been extended to Billroth I and total gastrectomy. The aim of this study is to review the state of laparoscopically performed gastrectomies in the international scene. METHODS: Questionnaires were prepared and sent to every surgeon in the world known by the authors or their contacts to have performed a laparoscopic gastrectomy. A questionnaire survey was started in July 1994 and completed by November 1994. Data collected included age, sex, type of gastric resection, technique of reconstruction after resection, average duration of surgery, time to liquid and solid intake, postoperative hospital stay, complications, and opinions of the surgeons. RESULTS: Sixteen surgeons contributed to this study. A total number of 118 cases of laparoscopic gastrectomies, comprising Billroth I (11), Billroth II (87), vagotomy and antrectomy (10), and total gastrectomy (10) had been performed. The indications were gastric and/or duodenal ulcers and benign and malignant gastric tumors. CONCLUSIONS: Laparoscopic gastrectomy was found to be superior to the open technique by 10 of 16 surgeons because of faster recovery, less pain, and better cosmesis. The procedure was an expensive and long operation according to four. Two surgeons were uncertain of any benefit because of limited experience.

Adult↗
PubMed1997

Predictive factors for synchronous common bile duct stones in patients with cholelithiasis.

BACKGROUND: To determine the predictive factors of synchronous common bile duct (CBD) stones, data from 878 consecutive patients who underwent cholecystectomy in a university clinic from June 1991 to June 1996 were retrospectively analyzed. METHODS: Based on clinical, biochemical, and ultrasonographic criteria, 194 patients were selected for ERCP, 180 preoperative and 14 postoperative. RESULTS: Cannulation of CBD was successful in 192 (99%) patients. Stones were identified in 62 (32%) patients and sphincterotomy was performed in 56 (90%). Duct clearance was achieved in 43 (77%) cases. There was a high predictive value for the presence of CBD stones in patients with cholangitis, present jaundice, and dilated CBD with evidence of stones on ultrasound (75%, 72%, and 67% respectively). A dilated CBD without stone on ultrasound and elevated liver enzymes had less than 40% positive predictive value. History of previous jaundice, pancreatitis, previously raised liver enzymes, and present pancreatitis was predictive in less than 20% of the cases. Univariate analyses revealed that clinical findings of cholangitis and obstructive jaundice, elevated liver enzymes (previous and present), and ultrasonographic findings of stones in a dilated CBD were significant positive predictors. Subanalysis of each elevated liver enzyme revealed that alanine transaminase, aspartate transaminase, alkaline phosphatase, and gamma glutamyl transpeptidase were significant predictors. Both elevated conjugated and total bilirubins were also significant predictors for CBD stones. CONCLUSION: Multivariate logistic regression analysis on these significant predictors showed that cholangitis (odds ratio [OR]: 10.5), dilated CBD with evidence of stones on ultrasound (OR: 7.4), elevated aspartate transaminase (OR: 2.9), and conjugated bilirubin (OR: 5.3) were jointly significant. The likelihood of having stones in the duct without any of these predictors was 7%, but 99% when all the predictors were positive.

Adolescent↗
PubMed1996

Randomized comparison of pulmonary function after the 'French' and 'American' techniques of laparoscopic cholecystectomy.

The 'French' and 'American' techniques of laparoscopic cholecystectomy, which differ in the position of the surgeon and ports, have not been compared directly. The authors' hypothesis was that the 'French' technique results in better postoperative pulmonary function than the 'American' technique. Patients undergoing elective cholecystectomy were randomized, 25 patients to have the 'French' method and 24 the 'American' method. Forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were measured before operation, and 6, 24 and 48 h after surgery. Postoperative pain and fatigue were also measured. Both FVC and FEV1 at 6 h, 24 h and 48 h after operation were significantly less in the 'American' group (FVC at 24 h: 71 versus 86 per cent of preoperative value; P = 0.001, Student's t test; 95 per cent confidence interval 7-24). Two cases of atelectasis occurred in the 'American' group and none in the 'French' group. Differences in access to Calot's triangle were also noted. One patient in the 'French' group sustained a diathermy injury of the duodenum, related to defective equipment. It is concluded that the 'French' method leads to less impairment of pulmonary function.

Cholecystectomy, Laparoscopic↗
PubMed1996

Laparoscopic cholecystectomy for acute cholecystitis: is it really safe?

The prospectively collected data from 530 cholecystectomies performed in a university clinic from October 1989 to March 1991 were analyzed after 1 to 3 years of follow-up. The aim of this study was to compare the results of laparoscopic cholecystectomy (LC) for acute cholecystitis with that for routine symptomatic gallbladders. The preoperative, intraoperative, and postoperative parameters of 424 routine (noninflamed) LCs and 54 LCs for acutely inflamed gallbladders were compared under the "intention to treat" principle. Operating time was longer in the inflamed group (median 97 minutes versus 75 minutes; p < 0.0001). Significantly more adhesions (20% versus 8%), more blood loss (48% versus 19%), a higher incidence of bile spillage (28% versus 12%), and lost stones (19% versus 8%) were encountered in patients with acute cholecystitis. Common bile duct (CBD) injuries were also more frequent in that group (5.5% versus 0.2%; p = 0.005). The rate of conversion to open surgery was higher than with routine LCs (13% versus 4%). There were two deaths in the routine LC group and none in the acutely inflamed group. There was no difference in postoperative pain intensity or postoperative fatigue according to visual analog scale measurements. Patients with acute cholecystitis stayed only 1 day longer (median 4 days versus 3 days) in hospital. The quality of life scores indicate return to almost normal values by the 14th postoperative day. Long-term follow-up (1-3 years) did not reveal any delayed clinical adverse effects. In summary, LC for inflamed gallbladders has a higher conversion rate than LC for routine symptomatic gallbladders. If successfully performed, it has definite benefit for the patient in terms of better postoperative recovery. The trade-off is that the risk of CBD injury is significantly higher.

Acute Disease↗
PubMed1996

Comparison between laparoscopic and conventional omental patch repair for perforated duodenal ulcer.

BACKGROUND: The aim of the study is to evaluate the safety and efficacy of laparoscopic omental patch repair. METHOD: This is a retrospective review of 53 consecutive patients with omental patch repair for perforated duodenal ulcer; 38 underwent conventional open approach and 15 underwent laparoscopic patch repair. The only selection criterion was availability of expertise for laparoscopic repair on the day of admission. By chance, the open group had poorer ASA scores. There were four deaths and five postoperative complications in the open group. RESULTS: Laparoscopic repair was successful in 14 cases with one postoperative complication. Operative time was longer in the laparoscopic group (80 vs 65 min in open group, p = 0.02). Patients required less postoperative analgesics in the laparoscopic group (median amount of pethidine was 75 mg vs 175 mg in the open group, p = 0.03). There was no statistically significant difference in terms of hospital stay and return to normal activities between the two procedures. Follow-up Visick scores were comparable in both groups. CONCLUSIONS: Laparoscopic omental patch repair offers a safe alternative to the conventional method and causes less postoperative pain.

Adolescent↗
PubMed1996

Endoscopic hemostasis of upper gastrointestinal bleeding with histoacryl: last resort before surgery.

Five patients presented with acute upper gastrointestinal bleeding, underwent diagnostic and therapeutic endoscopy. The source of bleeding was identified in each case. Two patients had a large chronic gastric ulcer, one had a stress ulcer, one had a gastric ulcer with hypertrophic gastropathy, and one had a malignant infiltration of the second part of the duodenum. Conventional first-line therapeutic modalities failed to induce hemostasis in these bleeding lesions. Hemostasis was successfully achieved in each case using an endoscopic intralesional injection of Histoacryl. This agent may represent a last resort for endoscopic hemostasis before surgery.

Aged↗
PubMed1996

H1-antagonism improves intestinal mucosal pH and heart function in porcine hypodynamic endotoxic shock.

Porcine hypodynamic shock was induced by continuous infusion of 5 micrograms lipopolysaccharide/kg per hour. This resulted in a decrease of cardiac output from baseline values of 3.5 +/- .9 L/min to 1.5 +/- .8 L/min and a reduced left ventricular stroke work index in the endotoxin-group (n = 6 animals). Pretreatment with the H1-antagonist dimethindene (2 mg/kg) in a second group (n = 6) significantly prevented these effects. Furthermore animals pretreated with the H1-antagonist showed a stable mean arterial blood pressure, whereas the control endotoxin-treated group revealed a drastic reduction in mean arterial blood pressure (99 +/- 4.7 mmHg versus 65.8 +/- 10 mmHg after 240 min, respectively). Pulmonary function and systemic vascular resistance were not ameliorated by the H1-antagonist in hypodynamic shock. Gastrointestinal mucosal pH (pHi), which indicates oxygenation of the mucosa, was decreased by endotoxin-infusion (7.45 +/- .32 baseline value to 6.92 +/- .24 after 120 min). This parameter as well as base excess values and lactate levels were significantly improved by dimethindene-pretreatment (p < .05). These results may indicate a beneficial effect of H1-antagonist-pretreatment on endotoxin-induced deterioration of the microcirculation. Furthermore our results clearly demonstrated that only pretreatment before endotoxemia with H1-antagonism is effective, since infusion of H1-antagonist in hypodynamic shock 45 min after addition of endotoxin (n = 6 animals) did not improve the cardiovascular system or the microcirculation.

Animals↗
PubMed1996

Preoperative ERCP in the management of common bile duct stones before laparoscopic cholecystectomy.

OBJECTIVE: To evaluate the effectiveness of a policy of preoperative endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic sphincterotomy (ES) before laparoscopic cholecystectomy. DESIGN: Retrospective review. SETTING: University hospital, Singapore. SUBJECTS. From January 1991 to December 1992, 303 patients underwent elective laparoscopic cholecystectomy, of which 46 (15%) were selected to have ERCP preoperatively because they had clinical, biochemical, and ultrasound signs of the presence of stones in the common bile duct (CBD). MAIN OUTCOME MEASURES: Effectiveness and efficiency of ERCP. RESULTS: Successful cannulation of the CBD was achieved in 45/46 cases (98%). In 19 patients (42%) stones were found, of which 18 (95%) were removed endoscopically. There were no major complications from the ERCP or the sphincterotomy. One patient developed symptoms from an unsuspected common duct stone two weeks after cholecystectomy and it was removed endoscopically. CONCLUSION: Selective preoperative ERCP is an effective and safe way of clearing the CBD before laparoscopic cholecystectomy, but its efficiency can be improved further by widening the criteria for preoperative ERCP and by doing operative cholangiography for patients with a low risk of stones in the CBD.

Adult↗
PubMed1996

Management of acute cholecystitis in the era of laparoscopic surgery.

Laparoscopic cholecystectomy for acute cholecystitis is a feasible but difficult operation that should only be performed by experienced laparoscopists. Specific modifications to the standard technique of laparoscopic cholecystectomy is described in this review. The conversion to open surgery rate is high, mostly due to dense adhesions obscuring Calot's triangle. However, if successfully completed without complications, the postoperative recovery is superior to the conventional procedure.

Acute Disease↗
PubMed1996

Laparoscopic-assisted large bowel resection.

Laparoscopic colon resection is a viable alternative to open colectomy. For non-malignant lesions, laparoscopic resection of the affected large bowel is attractive. For malignant lesions, where resection for cure is highly dependent on lymph node clearance, laparoscopic resection has met with criticisms regarding the adequacy of nodal clearance that can be achieved laparoscopically. Several published studies have shown that the operation though technically demanding, does not compromise the extent of resection. We report a series of 43 cases of laparoscopic colon resection done sequentially and successfully from January 1992 to June 1995. The operative time averaged 180 minutes (range 120 to 300 minutes). Five patients developed postoperative complications, which were mainly pulmonary and wound infections. There were no anastomotic leaks or perioperative deaths. The mean hospital stay was 5.3 days (range 4 to 9 days). By the third postoperative day, all patients were feeding and ambulatory. Long-term complications included one small bowel obstruction and one port site recurrence. In our selected group of patients, laparoscopic colon resection has not shown any adverse outcome. Prospective randomised studies are underway in various centres and their preliminary results are favourable.

Adult↗
PubMed1996

Laparoscopic exploration of the common bile duct-report on two cases and literature review.

The optimal management of the common bile duct stone in the era of laparoscopic surgery is not certain. The common policy is selective preoperative endoscopic retrograde cholangio-pancreatography (ERCP) followed by laparoscopic cholecystectomy. When ERCP fails, the common bile duct is explored via open surgery. New techniques of laparoscopic trancystic exploration of the common bile duct and laparoscopic choledochotomy exploration of the common bile duct are now being tried. The results of two case reports are discussed.

Adult↗
PubMed1995

Probability of adverse events that have not yet occurred: a statistical reminder.

The probability of adverse and undesirable events during and after operations that have not yet occurred in a finite number of patients (n) can be estimated with Hanley's simple formula, which gives the upper limit of the 95% confidence interval of the probability of such an event: upper limit of 95% confidence interval = maximum risk = 3/n (for n > 30). Doctors and surgeons should keep this simple rule in mind when complication rates of zero are reported in the literature and when they have not (yet) experienced a disastrous complication in a procedure.

Confidence Intervals↗