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H J Bonjer

Publications and source records attributed to H J Bonjer.

At least 19 recordsLinked to original sources
PubMed2004

Laparoscopic resection of colon Cancer: consensus of the European Association of Endoscopic Surgery (EAES).

BACKGROUND: The European Association of Endoscopic Surgery (EAES) initiated a consensus development conference on the laparoscopic resection of colon cancer during the annual congress in Lisbon, Portugal, in June 2002. METHODS: A systematic review of the current literature was combined with the opinions, of experts in the field of colon cancer surgery to formulate evidence-based statements and recommendations on the laparoscopic resection of colon cancer. RESULTS: Advanced age, obesity, and previous abdominal operations are not considered absolute contraindications for laparoscopic colon cancer surgery. The most common cause for conversion is the presence of bulky or invasive tumors. Laparoscopic operation takes longer to perform than the open counterpart, but the outcome is similar in terms of specimen size and pathological examination. Immediate postoperative morbidity and mortality are comparable for laparoscopic and open colonic cancer surgery. The laparoscopically operated patients had less postoperative pain, better-preserved pulmonary function, earlier restoration of gastrointestinal function, and an earlier discharge from the hospital. The postoperative stress response is lower after laparoscopic colectomy. The incidence of port site metastases is <1%. Survival after laparoscopic resection of colon cancer appears to be at least equal to survival after open resection. The costs of laparoscopic surgery for colon cancer are higher than those for open surgery. CONCLUSION: Laparoscopic resection of colon cancer is a safe and feasible procedure that improves short-term outcome. Results regarding the long-term survival of patients enrolled in large multicenter trials will determine its role in general surgery.

Colectomy↗
PubMed2004

Stress response to laparoscopic surgery: a review.

BACKGROUND: Laparoscopic surgery is associated with reduced surgical trauma, and therefore with a less acute phase response, as compared with open surgery. Impairment of the immune system may enhance surgical infections, port-site metastases, and sepsis. The objectives of this review was to assess immunologic consequences of benign laparoscopic surgery and to highlight controversial aspects. METHODS: A literature search on stress response to nonmalignant laparoscopic and open surgery was conducted using the MEDLINE and Cochrane databases. Cross-references from the reference list of major articles on the subject were used, as well as manuscripts published between 1993 and 2002. RESULTS: Local (i.e., peritoneal) immune function is affected by carbon dioxide pneumoperitoneum. The production of tumor necrosis factor and the phagocytotic capacity of peritoneal macrophages are less lowered. The systemic stress response, as determined by delayed-type hypersensitivity response and leukocyte antigen expression on lymphocytes, shows a preservation of immune function after laparoscopic surgery, as compared with conventional surgery. CONCLUSIONS: Intraperitoneal carbon dioxide insufflation attenuates peritoneal immunity, but laparoscopic surgery is associated with a lower systemic stress response than open surgery.

Acute-Phase Reaction↗
PubMed2004

Prevention of adhesion formation to polypropylene mesh by collagen coating: a randomized controlled study in a rat model of ventral hernia repair.

INTRODUCTION: In laparoscopic incisional hernia repair with intraperitoneal mesh, concern exists about the development of adhesions between bowel and mesh, predisposing to intestinal obstruction and enterocutaneous fistulas. The aim of this study was to assess whether the addition of a collagen coating on the visceral side of a polypropylene mesh can prevent adhesion formation to the mesh. METHOD: In 58 rats, a defect in the muscular abdominal wall was created, and a mesh was fixed intraperitoneally to cover the defect. Rats were divided in two groups; polypropylene mesh (control group) and polypropylene mesh with collagen coating (Parieten mesh). Seven and 30 days postoperatively, adhesions and amount and strength of mesh incorporation were assessed. Wound healing was studied by microscopy. RESULTS: With Parieten mesh, the mesh surface covered by adhesions was reduced after 30 days (42% vs 69%, p = 0.01), but infection rate was increased after both 7 (p = 0.001) and 30 days (p = 0.03), compared to the polypropylene group with no mesh infections. If animals with mesh infection were excluded in the analysis, the mesh surface covered by adhesions was reduced after 7 days (21% vs 76%, p = 0.02), as well as after 30 days (21 vs 69%, p < 0.001). Percentage of mesh incorporation was comparable in both groups. Mean tensile strength of mesh incorporation after 30 days was higher with Parieten mesh. CONCLUSION: Although the coated Parieten mesh was more susceptible to mesh infection in the current model, a significant reduction of adhesion formation was still seen with the Parieten mesh after 30 days, with comparable mesh incorporation in the abdominal wall.

Abdominal Wall↗
PubMed2004

Hematological long-term results of laparoscopic splenectomy for patients with idiopathic thrombocytopenic purpura: a case control study.

BACKGROUND: Laparoscopic splenectomy (LS) for idiopathic thrombocytopenic purpura (ITP) appears, when compared to open splenectomy (OS), associated with immediate important advantages. However, in a number of patients splenectomy does not lead to an adequate response, or after initial adequate response a relapse occurs after some time. A relapse may be associated to the presence of accessory spleens and splenosis. The purpose of this study was to compare the operative outcome and the hematological results on the long term of a series of LS with a historic series of OS for the treatment of ITP. METHODS: A retrospective review was done of 50 consecutive patients who underwent LS for ITP. Patient characteristics, outcome of surgery, and hematological results were compared to a historical group of patients who underwent conventional splenectomy for ITP (n = 31). Response to splenectomy was defined in three groups: complete remission, partial remission, and no response. Grouping was based on hematological data. RESULTS: Concerning operative outcome and postoperative complications, there was a significant difference in favor of LS. Moreover, the hematological outcome of both groups showed no differences after a median period of 66 months (OS) and 35 months (LS), respectively. CONCLUSIONS: Hematological results after laparoscopic splenectomy for ITP are comparable to those after open splenectomy in both the short and the long term.

Adolescent↗
PubMed2004

Surgical validation of unenhanced helical computed tomography in acute appendicitis.

BACKGROUND: Surgery for pain in the right lower quadrant of the abdomen remains a clinical dilemma. This prospective study assessed the accuracy of preoperative unenhanced helical computed tomography (CT) in the evaluation of patients with suspected acute appendicitis. METHODS: One hundred and three adult patients with suspected acute appendicitis underwent unenhanced helical CT of the abdomen. Subsequently, all patients underwent laparoscopic inspection of the abdominal cavity by a surgeon who was blinded to the diagnosis suggested by CT. Patients underwent appropriate surgical therapy accordingly. Follow-up was at least 6 weeks. RESULTS: Appendicitis was diagnosed by CT in 83 patients (80.6 per cent). Acute appendicitis was identified during laparoscopy in 87 patients (84.5 per cent). Prospective interpretation of CT images yielded a sensitivity of 95.4 per cent and a specificity of 100 per cent for the diagnosis of acute appendicitis. There were four false-negative scans. In 12 of 20 patients without signs of appendicitis on CT, the scan established the presence of other pathology. At operation no additional pathology was observed in this group and all other diagnoses proved to be correct. CONCLUSION: Plain helical CT in patients with suspected acute appendicitis provides an accurate diagnosis without the disadvantages of contrast enhancement.

Abdominal Pain↗
PubMed2004

Effect of laparoscopy on the immune system.

Surgery induces alterations in local and systemic immune responses. These changes appear to be associated with an increase in postoperative morbidity. Minimally invasive techniques are considered to improve the preservation of immune function compared with open surgery and may therefore be beneficial for patient recovery. As laparoscopic techniques are increasingly used in abdominal surgery, more research has focussed on the immunologic consequences of these techniques. Nevertheless, the changes that occur in response to trauma are still not completely understood. The immunologic benefits of laparoscopic surgery are the most obvious for minor surgical procedures such as cholecystectomy and antireflux surgery. For more complex procedures such as colorectal surgery for cancer, the benefits are not immediately obvious. Although laparoscopic surgery for colorectal malignancies may be associated with higher survival rates and lower recurrence rates because of improved immune function, it has also been related to high incidences of port-site metastases. Reviews in the literature have now shown that incidences of port-site metastases are comparable to incidences of wound metastases after open surgery. However, it will be necessary to wait for the long-term results of randomized, clinical trials to provide further clarification of how immune function is altered after laparoscopic and open surgery for colorectal cancer.

Acute-Phase Reaction↗
PubMed2003

Laparoscopic adhesiolysis in patients with chronic abdominal pain: a blinded randomised controlled multi-centre trial.

BACKGROUND: Laparoscopic adhesiolysis for chronic abdominal pain is controversial and is not evidence based. We aimed to test our hypothesis that laparoscopic adhesiolysis leads to substantial pain relief and improvement in quality of life in patients with adhesions and chronic abdominal pain. METHODS: Patients had diagnostic laparoscopy for chronic abdominal pain attributed to adhesions; other causes for their pain had been excluded. If adhesions were confirmed during diagnostic laparoscopy, patients were randomly assigned either to laparoscopic adhesiolysis or no treatment. Treatment allocation was concealed from patients, and assessors were unaware of patients' treatment and outcome. Pain was assessed for 1 year by visual analogue score (VAS) score (scale 0-100), pain change score, use of analgesics, and quality of life score. Analysis was by intention to treat. FINDINGS: Of 116 patients enrolled for diagnostic laparoscopy, 100 were randomly allocated either laparoscopic adhesiolysis (52) or no treatment (48). Both groups reported substantial pain relief and a significantly improved quality of life, but there was no difference between the groups (mean change from baseline of VAS score at 12 months: difference 3 points, p=0.53; 95% CI -7 to 13). INTERPRETATION: Although laparoscopic adhesiolysis relieves chronic abdominal pain, it is not more beneficial than diagnostic laparoscopy alone. Therefore, laparoscopic adhesiolysis cannot be recommended as a treatment for adhesions in patients with chronic abdominal pain.

Abdomen↗
PubMed2003

Abdominal adhesions: intestinal obstruction, pain, and infertility.

Adhesions cause bowel obstruction, chronic abdominal pain, and infertility. In this review, the incidence, clinical signs, diagnostic procedures, and treatment of these sequels of abdominal surgery are discussed. Laparoscopic treatment of bowel obstruction, chronic pain, and infertility is feasible in selected patients and has been reported to cause fewer newly formed adhesions. Randomized controlled trials to compare open and laparoscopic surgery for adhesions should be executed with long-term follow-up to assess the success rates of adhesiolysis and compare the morbidity and mortality.

Abdominal Pain↗
PubMed2003

Laparoscopic resection of colonic cancer.

Laparoscopic resection of colonic cancer can be regarded as a safe and efficacious procedure. Short-term outcome is better after laparoscopic colectomy than after open colectomy. Long-term results of the first published randomized clinical trial indicate improved cancer related survival following laparoscopic resection of colonic cancer. However, patients included in this single center study were operated on by highly experienced laparoscopic surgeons and included relative small numbers of patients. Results of other large randomized controlled trials have to be awaited before laparoscopic resection can be recommended for colonic cancer. Higher in-hospital costs and a long learning curve hinder rapid implementation of laparoscopic colectomy into general surgical practice. Integration of laparoscopic surgery into surgical training programs is mandatory.

Colectomy↗
PubMed2002

Safe laparoscopic adhesiolysis with optical access trocar and ultrasonic dissection. A prospective study.

BACKGROUND: The objective of this clinical study was to examine the feasibility, safety, and adequacy of hemostasis of combined use of an optical trocar and ultrasonic dissection in laparoscopic adhesiolysis in patients with chronic abdominal pain. METHODS: In 105 patients, identification of anatomic layers of the abdominal wall, establishment of pneumoperitoneum, completeness of adhesiolysis, hemostasis, and complications and pain relief were studied. RESULTS: All abdominal wall layers could be determined during introduction as well as adherence of intraabdominal organs at the introduction site. Ultrasonic dissection enables an (almost) complete adhesiolysis in 103 (98%) patients and offered adequate hemostasis in 101 (96%) patients. Four perforations during laparoscopic adhesiolysis and no late (thermal) perforations were observed. CONCLUSIONS: With an optical trocar a safe introduction site of the abdominal wall can be chosen. The ultrasonic technique offers a sound adhesiolysis with adequate hemostasis and fewer thermal perforations and adds to feasibility and safety of laparoscopic adhesiolysis.

Abdominal Pain↗
PubMed2002

Tensile strength of mesh fixation methods in laparoscopic incisional hernia repair.

BACKGROUND: Fixation of the mesh is crucial for the successful laparoscopic repair of incisional hernias. In the present experimental study, we used a pig model to compare the tensile strengths of mesh fixation with helical titanium coils (tackers) and transabdominal wall sutures. METHODS: Thirty-six full-thickness specimens (5 x 7 cm) of the anterior abdominal wall of nine pig cadavers were randomized for fixation of a polypropylene mesh (7 x 7 cm) by either tackers or transabdominal wall sutures. The number of fixation points varied from one to five per 7-cm tissue length, with distances between fixation points of 2.3, 1.8, 1.4, and 1.2 cm, respectively. The force required to disrupt the mesh fixation (tensile strength) was measured by a dynamometer. Statistical analysis was performed using the Wilcoxon test and the Spearman rank correlation test. RESULTS: The mean tensile strength of mesh fixation by transabdominal sutures was significantly greater than that by tackers for each number of fixation points: 67 N vs 28 N for a single fixation point (p <0.001), 115 N vs 42 N for two fixation points (p <0.001), 150 N vs 63 N for three fixation points (p <0.05), 151 N vs 73 N for four fixation points (p <0.05), and 150 N vs 82 N for five fixation points (p <0.05). Increasing the number of fixation points over three per 7 cm (distance between fixation points of 1.8 cm) did not improve tensile strength. CONCLUSION: The tensile strength of transabdominal sutures is up to 2.5 times greater than the tensile strength of tackers. Therefore, the use of transabdominal sutures for mesh fixation appears to be preferable for laparoscopic incisional hernia repair.

Abdominal Wall↗
PubMed2002

Complications and feasibility of laparoscopic adhesiolysis in patients with chronic abdominal pain. A retrospective study.

BACKGROUND: A retrospective study was done to determine whether laparoscopic adhesiolysis benefits patients with chronic abdominal pain. Factors that influence complications and feasibility of laparoscopic adhesiolysis were evaluated. METHODS: 174 consecutive operations in 157 patients were retrospectively analyzed for factors which might influence the complication rate and the feasibility of laparoscopic adhesiolysis. RESULTS: In 128 out of 174 procedures a complete adhesiolysis was performed. We had to accept an incomplete adhesiolysis in 39 other patients and in 7 patients a primary conversion was needed. We noticed 16 major complications. Two patients died. Relief of pain was recorded in 80% of patients after short follow-up. The number of previous abdominal operations and patient age significantly affected the outcome of surgery. CONCLUSION: Laparoscopic adhesiolysis in patients with chronic abdominal pain seems to be a feasible and effective operation with considerable risk.

Abdominal Pain↗
PubMed2002

Impact of carbon dioxide and helium insufflation on cardiorespiratory function during prolonged pneumoperitoneum in an experimental rat model.

BACKGROUND: Experimental studies on laparoscopic surgery are often performed in rats. However, the hemodynamic and respiratory responses related to the pneumoperitoneum have not been studied extensively in rats. Therefore, the aim of this study was to investigate in spontaneously breathing rats the effects of CO2 and helium, insufflation pressure, and duration of pneumoperitoneum on blood pressure, arterial pH, pCO2, pO2, HCO3-, base excess, and respiratory rate. METHODS: Five groups of 9 Brown Norway rats were anesthetized and underwent CO2 insufflation (6 or 12 mmHg), helium insufflation (6 or 12 mmHg), or abdominal wall lifting (gasless control) for 120 min. Blood pressure was monitored by an indwelling carotid artery catheter. Baseline measurements of mean arterial pressure (MAP), respiratory rate, arterial blood pH, pCO2, pO2, HCO3-, and base excess were recorded. Blood gases were analyzed at 5, 30, 60, 90, and 120 min during pneumoperitoneum, and MAP and respiratory rate were recorded at 5 and 15 min and at 15-min intervals thereafter for 2 h. RESULTS: CO2 insufflation (at both 6 and 12 mmHg) caused a significant decrease in blood pH and increase in arterial pCO2. Respiratory compensation was evident since pCO2 returned to preinsufflation levels during CO2 insufflation at 12 mmHg. There was no significant change in blood pH and pCO2 in rats undergoing either helium insufflation or gasless procedures. Neither insufflation pressure nor the type of insufflation gas had a significant effect on MAP over time. CONCLUSION: The cardiorespiratory changes during prolonged pneumoperitoneum in spontaneously breathing rats are similar to those seen in clinical practice. Therefore, studies conducted in this animal model can provide valuable physiological data relevant to the study of laparoscopic surgery.

Animals↗
PubMed2002

Technical considerations and pitfalls in laparoscopic live donornephrectomy.

BACKGROUND: Recent developments in laparoscopic solid organ surgery suggest a possible reduction in postoperative discomfort and disability for kidney donors. Technical aspects and the influence of surgical experience in laparoscopic donor nephrectomy were evaluated. METHODS: The clinical outcome of 57 laparoscopic donor nephrectomies (LapNx) was compared with that for a historic control group of 27 open donor nephrectomies (OpenNx). RESULTS: Three conversions to open nephrectomy (5.2%) were necessary. Postoperative complications were minor and comparable in both groups. Patients who underwent laparoscopic surgery demonstrated significantly less postoperative pain and a shorter hospital stay, but operative time and warm ischemia time were significantly longer. Graft survival after LapNx was 100% during a median follow-up period of 13 months. Operative time for LapNx decreased considerably with experience gained and seemed to be less for right nephrectomy. Stenotic ureter-bladder anastomoses occurred after LapNx in four patients during the first half year (7.0%), but this problem seemed to be resolved after modification of the technique. CONCLUSION: LapNx is associated with less postoperative discomfort and improved convalescence.

Case-Control Studies↗
PubMed2002

Meta-analysis of techniques for closure of midline abdominal incisions.

BACKGROUND: Various randomized studies have evaluated techniques of abdominal fascia closure but controversy remains, leaving surgeons uncertain about the optimal method of preventing incisional hernia. METHOD: Medline and Embase databases were searched. All trials with a follow-up of at least 1 year that randomized patients with midline laparotomies to closure of the fascia by different suture techniques and/or suture materials were subjected to meta-analysis. Primary outcome was incisional hernia; secondary outcomes were wound dehiscence, wound infection, wound pain and suture sinus formation. RESULTS: Fifteen studies were identified with a total of 6566 patients. Closure by continuous rapidly absorbable suture was followed by significantly more incisional hernias than closure by continuous slowly absorbable suture (P < 0.009) or non-absorbable suture (P = 0.001). No difference in incisional hernia incidence was found between slowly absorbable and non-absorbable sutures (P = 0.75), but more wound pain (P < 0.005) and more suture sinuses (P = 0.02) occurred after the use of non-absorbable suture. Similar outcomes were observed with continuous and interrupted sutures, but continuous sutures took less time to insert. CONCLUSION: To reduce the incidence of incisional hernia without increasing wound pain or suture sinus frequency, slowly absorbable continuous sutures appear to be the optimal method of fascial closure.

Hernia, Ventral↗
PubMed2002

Mesh repair of incisional hernia: comparison of laparoscopic and open repair.

OBJECTIVE: To compare our results of open and laparoscopic mesh repair of incisional hernias. DESIGN: Retrospective cohort study. SETTING: Teaching hospitals, The Netherlands. SUBJECTS: All patients who had had a laparoscopic (n = 25) or an open (n = 76) mesh repair of incisional hernia between January 1996 and January 2000. INTERVENTIONS: Physical examination at the time of the study. MAIN OUTCOME MEASURES: Morbidity and recurrence. RESULTS: The groups were comparable. 11 patients (14%) developed postoperative infections after open repair and 1 (4%) after laparoscopic repair (p = 0.29). Median hospital stay was 5 days (range 1-19) in the open group and 4 (range 1-11) in the laparoscopic group (p = 0.28). The 2-year cumulative incidence of recurrence was 18% after open repair (median follow-up of 17 months (range 1-46) and 15% after laparoscopic repair (median follow-up of 15 months, range 1-44). Recurrences in the laparoscopic group were all among the first 7 cases in which the mesh was fixed with staples alone. CONCLUSION: There were fewer infections and hospital stay was shorter in the laparoscopic group, but not significantly so. Recurrence rates were comparable.

Adult↗
PubMed2002

The value of plasma markers for the clinical behaviour of phaeochromocytomas.

OBJECTIVE: Phaeochromocytomas (PCCs) are widely known for their clinical unpredictability. This study intends to define predictive plasma markers for their variable postoperative behaviour. Furthermore, the diagnostic accuracy of these plasma tests was determined. DESIGN AND METHODS: A retrospective correlative study was performed in a series of 83 operated and four autopsied patients in order to correlate preoperative catecholamine (CAT) levels of 103 PCCs with their clinical behaviour. In a subset of cases, chromogranin-A (Chr-A) and enzymes/precursors of the CAT biosynthesis were studied for their predictive value. RESULTS: Basal CAT levels were elevated in 81/87 instances (sensitivity: 93%). Four of six cases with normal measurements showed only medullary hyperplasia. Larger PCCs, particularly those showing necrosis, capsular and vascular invasion, secreted higher CAT levels. Bilateral, hereditary tumours were less productive than their unilateral counterparts. Extra-adrenal PCCs secreted significantly lower levels of epinephrine (EPI) than intra-adrenal tumours. Fourteen patients developed metastases. According to Kaplan-Meier estimations, patients with higher levels of dopamine, norepinephrine (NE) and aromatic l-amino acid decarboxylase as well as lower ratios of EPI/EPI+NE, had significantly shorter metastases-free intervals. Existence of preoperative hypertension, left ventricular hypertrophy and measured blood pressures showed significant positive relationships with CAT levels, but not with Chr-A. CONCLUSIONS: These data showed that plasma CAT measurement is a sensitive method in the diagnostic work-up of PCCs. Those tumours producing normal levels are commonly small and asymptomatic. Furthermore, certain secretion patterns are indicative of the presence of metastases as well as the size and site of sporadic and syndrome-related PCCs.

Adolescent↗