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Biomedical subjects

W A Bemelman

Publications and source records attributed to W A Bemelman.

At least 19 recordsLinked to original sources
PubMed2000

Prolonged ambulatory recording of antroduodenal motility in slow-transit constipation.

BACKGROUND: Slow-transit constipation may be part of a pan-enteric motor disorder. To test this hypothesis 24-h ambulatory antroduodenal manometry was performed and orocaecal transit time determined in patients with slow-transit constipation and in healthy controls. METHODS: Antroduodenal motility was recorded with a five-channel solid-state catheter. Postprandial motility was recorded after consumption of two standardized test meals and interdigestive motility was recorded nocturnally. Manometry tracings were analysed for quantitative and qualitative abnormalities. Orocaecal transit time was determined by means of the lactulose hydrogen breath test. RESULTS: Postprandial motility was no different between patients and controls. However, some minor changes of interdigestive motility were observed. The proportion of phase II activity of the nocturnal cycles of the interdigestive migrating motor complex was increased in patients while phase I activity was decreased. The total number of observed phase III fronts was no different in patients and controls, although the number of phase III fronts with antral onset was decreased. Furthermore, the amplitude of phase III activity of duodenal onset was also decreased. Specific motor abnormalities such as retrograde propagation of phase III fronts were more frequent in patients. Orocaecal transit time was delayed in patients. CONCLUSION: In patients with slow-transit constipation, orocaecal transit time is delayed but antro- duodenal motility is generally well preserved with only minor alterations. Presented as a poster to the Digestive Disease Week meeting in New Orleans, Louisiana, USA, May 1998, and published in abstract form as Gastroenterology 1998; 114: A820

Adolescent↗
PubMed1999

[Pysical examination--rebound tenderness].

Rebound tenderness is generally practiced in the diagnosis of acute abdominal pain. It is a test that inflicts much discomfort to the patient. Literature data derived from reports assessing the reliability of the diagnosis of acute appendicitis indicate a sensitivity of 0.78-0.91 (pooled: 0.91) and a specificity of 0.48-0.60 (pooled: 0.60) of rebound tenderness. It would appear that rebound tenderness is a test of little specificity (leading to many false positive results) and that it has very little additional value, particularly in the presence of local tenderness and/or rigidity in patients with acute abdominal pain.

Abdomen, Acute↗
PubMed1999

Laparoscopically assisted bowel surgery for inflammatory bowel disease. The combined experiences of two academic centers.

BACKGROUND: Laparoscopic bowel surgery was evaluated in 44 consecutive patients who underwent surgery for inflammatory bowel disease (IBD). We studied feasibility, results, and final outcome. METHODS: At two academic institutes, 44 laparoscopically assisted colectomies and laparoscopic ileostomies or colostomies were attempted. All patients had histologically proven IBD and no prior surgery for IBD. Loop ileostomy (n = 4), end colostomy (n = 1), ileocecal resection (n = 26) and (procto)colectomy (n = 13) were performed. All resections were laparoscopically assisted with extracorporal resection and anastomosis. RESULTS: Only in two patients (ileocecal resection in both) was conversion to open surgery necessary. Two patients with laparoscopic ileocolic resection had intra-abdominal abscesses, which were drained percutaneously in both. One patient in the laparoscopically assisted colectomy group had a subphrenic abscess that was drained percutaneously, and one patient had a generalized candidiasis. CONCLUSIONS: Laparoscopically assisted colectomies can be performed safely in treating IBD. The laparoscopic method with use of a small vertical umbilical or Pfannenstiel's incision seems acceptable with regard to operating time and overall costs, also allowing superior cosmesis to be maintained.

Adolescent↗
PubMed1999

Treatment of mesenteric desmoid tumours with the anti-oestrogenic agent toremifene: case histories and an overview of the literature.

Desmoid tumours are histologically benign but due to their infiltration and compression of surrounding structures potentially life-threatening fibromatous lesions of unknown aetiology. The annual incidence rate is 2-4 per million people. The mesenteric variant constitutes about 10% of all desmoid tumours, although in familial adenomatous polyposis (FAP) patients this may be up to 70%. Due to the small number of patients with mesenteric desmoids the therapy is mainly empirical. This report describes the rationale as well as the value of the short- and long-term treatment (up to 6 years) with the anti-oestrogenic agent toremifene in combination with sulindac in two patients suffering from such a mesenteric desmoid tumour. These patients did not respond to sulindac alone and previous treatment with tamoxifen together with this non-steroidal anti-inflammatory drug had also failed. An overview of the literature on the management of these dismal tumours is presented.

Adult↗
PubMed1998

Cosmesis and body image after laparoscopic-assisted and open ileocolic resection for Crohn's disease.

BACKGROUND: The objectives of this study were to evaluate body image, cosmetic results, and quality of life in patients with Crohn's disease of the terminal ileum who had either laparoscopic-assisted or open ileocolic resection, and to determine how patients experienced the pre- and postoperative periods after both procedures. METHODS: Thirty-four patients participated: 11 patients after open resection (OR), 11 patients after laparoscopic-assisted resection (LR), and 12 patients without resection (WR). Retrospectively, the patients filled out several questionnaires pertaining to body image, hospital experiences, and quality of life. One-way analysis of variance, Student's t-tests, and Pearson's correlation were used for statistical analysis. RESULTS: The cosmetic score was significantly higher in the LR than in the OR group (p < 0.01). Body image correlated strongly with cosmesis and with quality of life. The hospital experiences of the laparoscopic and open groups were similar. CONCLUSIONS: Laparoscopic surgery was associated with better cosmesis than open surgery. Patients do not experience laparoscopic surgery any differently from open surgery.

Adolescent↗
PubMed1998

Management of recurrent Crohn's disease.

After partial small bowel or colonic resection for Crohn's disease, recurrence frequently follows. Within half a year 60-73% of patients have endoscopic recurrence. This percentage increases substantially in as time passes. Symptoms will not always be present when endoscopic lesions are detected. The etiology of recurrent Crohn's disease is unknown. Some studies show that initial complications or extra-intestinal manifestations are more frequently seen in patients with a recurrence. The recurrent pattern of the lesions is also comparable to the pre-surgical state. The length of recurrent ileal inflammation after ileocolonic resection correlates with the pre-surgical extent of the disease. Some investigators have found electron-microscopic lesions in histologically unaffected resection margins demonstrating the presence of lesions. Luminal factors probably plays an important role as bypassing an anastomosis prevents an endoscopic recurrence. Some factors are considered to be important to increase the chance of a recurrence. A more aggressive disease may lead to earlier recurrence. Onset of disease at a younger age, a short pre-operative time, and localization, might play an important role. Smoking certainly influences the clinical, endoscopic and surgical recurrence. The number of daily cigarettes smoked and the duration of smoking, significantly increases the risk of recurrence. The type of surgery (kind of anastomosis, multiple anastomoses, length of resection) are not important. A longer macroscopic disease-free resection margin or presence of granuloma does not influence the recurrence rate. Also, the presence of microscopic disease at the margin is not important. Prevention of recurrent disease can be provided by administrating sulphasalazine, 5-aminosalicylic acid or metronidazole. For this reason, prophylactic medication after surgical resection seems appropriate.

Anastomosis, Surgical↗
PubMed1998

Laparoscopic-assisted bowel resections in inflammatory bowel disease: state of the art.

The objectives of this paper are to review the rational, the present results and future of laparoscopic-assisted bowel surgery in patients with inflammatory bowel disease (IBD). Only a few centres in the world report on laparoscopic bowel resection in IBD that include stoma surgery, ileocolic resection, left, right and (sub)total colectomy for Crohn's disease, and subtotal or restorative total proctocolectomy (ileal pouch anal procedures). The combined series report conversion rates between 2.5% and 22.2%. Ileocolic resection, stoma creation, stricturoplasty and segmental small bowel resection are associated with an acceptable length of surgery, but laparoscopic(-assisted) total colectomy or restorative proctocolectomy still demand up to 4-6 hours of operative time. The few randomised studies addressing laparoscopic-assisted (segmental) bowel surgery versus conventional surgery demonstrated significantly less pain, a quicker return to self-care and a shorter hospital stay. The results of the series reporting on laparoscopic-assisted (ileo)colectomy in IBD are similar to those from these randomised studies. Laparoscopic-assisted subtotal colectomy and restorative proctocolectomy have no benefit compared with conventional surgery other than superior cosmesis. Morbidity of laparoscopic (ileo)colectomy in IBD is low, that of laparoscopic-assisted subtotal colectomy and restorative proctocolectomy remains to be seen. The various laparoscopic bowel resections done in IBD are all feasible. The first series describing laparoscopic surgery for IBD indicate that laparoscopic-assisted segmental (ileo)colectomy is safe and is the preferred approach provided it is done in a centre specialised in the treatment of IBD and by skilled laparoscopic surgeons beyond the learning curve. Until now, laparoscopic-assisted subtotal colectomy and restorative proctocolectomy do not have the same short-term benefits as seen in other laparoscopic colorectal procedures. Patients with inflammatory bowel disease (IBD) have a high life-time risk of having abdominal surgery and reoperations. The proposed advantages of laparoscopic surgery in this group of young patients might be higher than in patients with other colorectal diseases. Minimal physiologic insult in patients who already are under significant physiologic stress, less adhesion formation and superior cosmesis are important benefits over time. In a time where patient's demands will increase, the future of laparoscopic colonic surgery in IBD looks assured.

Anastomosis, Surgical↗
PubMed1997

Origin of endotoxemia influences the metabolic response to endotoxin in dogs.

Different routes of endotoxin administration have been used to mimic inflammatory and metabolic responses observed during sepsis. Because the origin of endotoxemia may affect the reactions to endotoxin, we compared the induction of tumor necrosis factor (TNF), interleukin-6 (IL-6), hormones, and glucose production after endotoxin (1.0 microg/kg Escherichia coli 0111:B4) administration into a peripheral (n = 8) versus the portal (n = 8) vein in anesthetized dogs. Prior to endotoxin, a laparotomy was performed for cannulation of hepatic vessels. To evaluate the effects of surgery and anesthesia, we also studied the effects of peripheral endotoxin administration in six awake dogs. The rate of appearance of glucose was measured by primed continuous infusion of [6,6-2H2]glucose. In anesthetized dogs, arterial concentrations of TNF and IL-6 increased after endotoxin administration (P < 0.01 vs basal; NS between groups). Net hepatic TNF production was increased after endotoxin administration (peripheral vs portal endotoxin administration: 533 +/- 177 vs 2135 +/- 1127 ng/min, both P < 0.05 vs basal; NS between groups). Net hepatic IL-6 production was stimulated only after portal endotoxin delivery (from 86 +/- 129 to 4740 +/- 1899 ng/min, P < 0.05; NS between groups). Although there were no differences in neuroendocrine activation, portal endotoxin administration resulted in decreased glucose production compared with peripheral administration (13.6 +/- 0.9 vs 16.8 +/- 1.2 micromol/kg.min, P < 0. 05). In contrast to anesthetized dogs, endotoxin increased glucose production considerably in awake dogs from 13.8 +/- 1.2 to 24.2 +/- 3.2 micromol/kg.min (P < 0.05; P < 0.05 vs anesthetized dogs). The contribution of anesthesia and surgery increased the endotoxin-induced IL-6 response by approximately 350% compared with the effect of endotoxin in awake dogs (P < 0.01). In conclusion, there are no major differences in the responses to endotoxin between peripherally treated and portally treated dogs, except for differences in glucose production. Portal delivery compared with systemic delivery of endotoxin alters hepatic metabolism through nonendocrine mechanisms, reflected in decreased glucose production. The inflammatory, endocrine, and metabolic effects of endotoxin are altered by the combination of surgery and anesthesia.

Anesthesia↗
PubMed1997

Laparoscopic cholecystectomy using abdominal wall retraction. Hemodynamics and gas exchange, a comparison with conventional pneumoperitoneum.

BACKGROUND: Disadvantages related to CO2 pneumoperitoneum have led to development of the abdominal wall retractor (AWR), a device designed to facilitate laparoscopic surgery without conventional pneumoperitoneum (15 mmHg CO2). We investigated the effects of the AWR on hemodynamics and gas exchange in humans. We also investigated whether the use of an AWR imposed extra technical difficulties for the surgeon. A pilot study revealed that cholecystectomy without low-pressure pneumoperitoneum was technically impossible. METHODS: A prospective randomized controlled trial: Twenty patients undergoing laparoscopic cholecystectomy were randomly allocated into group 1: AWR with low-pressure pneumoperitoneum (5 mmHg), or group 2: conventional pneumoperitoneum (15 mmHg). RESULTS: Surgery using the AWR lasted longer, 72 +/- 16 min (mean +/- SD) vs 50 +/- 18 min compared with standard laparoscopic cholecystectomy. There were no differences between the groups with respect to hemodynamic parameters, although a small reduction of the cardiac output was observed using conventional pneumoperitoneum (from 3.9 +/- 0.7 to 3. 2 +/- 1.1 l/min) and an increase during AWR (from 4.2 +/- 0.9 to 5.2 +/- 1.5 l/min). Peak inspiratory pressures were significantly higher during conventional pneumoperitoneum compared to AWR. A slight decrease in pH accompanied by an increase in CO2 developed during pneumoperitoneum and during the use of the AWR. In both groups arterial PO2 decreased. CONCLUSIONS: The results indicate that the view was impaired during use of the AWR and therefore its use was difficult and time-consuming. Possible advantages of this devices' effects on hemodynamics and ventilatory parameters could not be confirmed in this study.

Abdominal Muscles↗
PubMed1997

Laparoscopic surgery in Crohn's disease.

In a prospective study the feasibility and safety of laparoscopic-assisted ileocaecal resection for Crohn's disease was studied and compared with 16 patients who had open ileocaecal resection, and the value of laparoscopic stoma surgery was assessed. From January to November 1995 laparoscopic-assisted ileocaecal resection for Crohn's disease was undertaken in 7 patients, laparoscopic-assisted stoma formation in 10 patients. In 1 patient laparoscopic ileocaecal resection was converted to open surgery due to an unrecognised ileocolic fistula. Operating time in laparoscopic-assisted ileocaecal resections was longer than in open ileocaecal resection (150 vs. 127 min, P = 0.7). Blood loss (386 vs. 445 ml, P = 0.7), first bowel movement (3.5 vs. 4.9 postoperative days, P = 0.07) and postoperative time to discharge (5.2 vs. 9.9 days, P < 0.01) in patients who had a laparoscopic-assisted ileocaecal resection were less than in patients who had open surgery. In all 10 patients laparoscopic formation of a stoma was possible. Operating time was 62 min. Oral solids were restored on the 1.5 postoperative day. Mean postoperative stay was 8.8 days, prolonged due to time needed for stoma-care training. These preliminary results indicate that laparoscopic-assisted ileocaecal resection and stoma surgery for Crohn's disease are feasible and safe. Both procedures are characterised by rapid recovery and superior cosmetic results.

Adult↗
PubMed1997

The decrease in nonsplenic interleukin-6 (IL-6) production after splenectomy indicates the existence of a positive feedback loop of IL-6 production during endotoxemia in dogs.

The spleen is involved in endotoxin-induced interleukin-6 (IL-6) production. To quantitate the relative contribution of the spleen to endotoxin-induced IL-6 production, we studied the effect of endotoxin (1.0 microg/kg of body weight) in control dogs (n = 7) and splenectomized dogs (n = 7). Blood for analysis of tumor necrosis factor (TNF) and IL-6 was sampled from the femoral artery and the portal, hepatic, and splenic (only in controls) veins. Arterial plasma endotoxin and cortisol levels were also measured. Whole-body IL-6 production was calculated by a deconvolution technique. Splenic IL-6 production in control dogs was measured from splenic blood flow and arteriovenous concentration differences. Endotoxin levels were higher in splenectomized dogs (P < 0.05) because of a decreased distribution volume (P < 0.05) and decreased clearance of endotoxin (P < 0.05). Endotoxin-induced plasma IL-6 levels were decreased by approximately 75% in splenectomized dogs (P < 0.01), and whole-body IL-6 production rates were severalfold lower (median of 8.7 mg/4 h and range of 3.9 to 11.4 mg/4 h versus a median of 32.3 mg/4 h and a range of 22.7 to 70.2 mg/4 h) (P < 0.05). However, in control dogs splenic IL-6 production (0.6 +/- 0.2 mg/4 h) was only approximately 2% of whole-body IL-6 production. Plasma TNF levels increased in both groups (P < 0.01) but were not different between the groups. Plasma cortisol levels were slightly higher in splenectomized dogs than in control dogs (P < 0.05). In conclusion, splenectomy decreases the distribution volume and clearance rate of endotoxin. Splenectomy results in decreased endotoxin-induced IL-6 production, which is caused not by the absence of splenic IL-6 production, but by a decrease in nonsplenic IL-6 production. Therefore, the spleen is an important mediator in the complete activation of nonsplenic IL-6 production by endotoxin.

Animals↗
PubMed1996

Laparoscopic-assisted colectomy with the dexterity pneumo sleeve.

UNLABELLED: The dexterity pneumo sleeve is designed to provide abdominal access for the surgeon's hand while preserving pneumoperitoneum during laparoscopy. The first experience using the dexterity pneumo sleeve in colorectal surgery is reported. METHODS: Four patients with diverticulitis and one with a dolichocolon had manually assisted laparoscopic sigmoid colectomy with the dexterity pneumo sleeve. RESULTS: Assistance of the left hand, introduced through the dexterity device proved to be extremely helpful in identifying the plane of dissection in one patient with a large diverticular mass and in another with a colovaginal fistula. Mean operative time was 109 minutes, blood loss was 80 ml, and length of incision was 7.5 cm. Flatus reoccurred at the second postoperative day, bowel movement occurred on the third day after surgery, and patients were discharged after 4.8 days. CONCLUSIONS: With the dexterity pneumo sleeve, the tactile sensation is regained, which makes laparoscopic-assisted colectomy safer and faster.

Blood Loss, Surgical↗
PubMed1996

Complications of an implantable venous access device (Port-a-Cath) during intermittent continuous infusion of chemotherapy.

In 149 patients, treated with intermittent continuous infusion of different chemotherapeutic agents, 169 Port-a-Caths were implanted by qualified surgeons and residents in training. The peri- and postoperative complications of implantation of the Port-a-Cath system and the complications during treatment were retrospectively analysed. The Port-a-Cath was in situ for a total of 36247 days (median 181, range 1-1332). Of the 169 catheters, major complications occurred during treatment, with infection in 4 patients (2.4%), occlusion in 3 (1.8%), thrombosis in 8 (4.7%), extravasation in 8 (4.7%) and migration in 3 (1.8%). The peri- and postoperative complication rate was low, although pneumothorax occurred in 6 patients (3.6%). In 25 patients (14.8%) the Port-a-Cath had to be explanted due to complications. It can be concluded that continuous infusion of chemotherapy via a Port-a-Cath system is a relatively safe procedure, although major complications do occur. The experience of the surgeon could not be related to the complications.

Adult↗
PubMed1996

Laparoscopic ultrasonography for staging of gastrointestinal malignancy.

BACKGROUND: Diagnostic laparoscopy has been used frequently as a preoperative staging procedure for different gastrointestinal malignancies. The assessment of solid abdominal organs and retroperitoneal ingrowth or detection of lymph-node metastasis is limited, however. A recent development, laparoscopic ultrasonography, will probably increase the preoperative evaluation of these lesions and thus further improve the preoperative staging. METHOD: Since 1993 diagnostic laparoscopy combined with laparoscopic ultrasonography has been performed as an additional diagnostic procedure in patients who have already been selected for curative resection of different GI malignancies. In this prospective study, staging after conventional work-up is compared with the tumour stage after laparoscopy. All patients underwent exploratory laparotomy except those with histologically proven metastases/ingrowth. RESULTS: For patients with cancer of the esophagus and gastric cardia (n = 56) the preoperative stage was altered in 17% but laparotomy could only be avoided in 5% (for a subgroup of patients with a tumour of the gastric cardia laparotomy was avoided in 11%). Additional findings during laparoscopy showed that laparotomy could be avoided in 55% of the patients (n = 44) with primary liver tumours, liver metastasis or proximal bile duct tumours. For patients with pancreatic head tumours (n = 73) the preoperative stage of the tumor changed in 40%; the strategy of treatment was changed in 26% and laparotomy could be avoided in 20%. CONCLUSIONS: Laparoscopy combined with laparoscopic ultrasonography is effective (more accurate) in the staging of gastrointestinal malignancies, in particular for patients with liver, biliary and pancreatic tumours. The preoperative tumour stage changed between 15 and 60% for the different gastrointestinal malignancies and laparotomy could be avoided in 5-55%. The procedure is highly operator-dependent and has a learning curve.

Endosonography↗
PubMed1996

Comparison of laparoscopic and transabdominal ultrasonography in staging of cancer of the pancreatic head region.

The value of laparoscopic ultrasonography in the staging of cancer of the pancreatic head region was compared prospectively to that of transabdominal ultrasonography. Eighty patients underwent LUS, after ultrasonography had shown normal Doppler findings of portal vessels and no signs of metastatic disease. Presence of hepatic or lymph node metastases and vascular tumor infiltration were evaluated in 74 and 48 patients, respectively. Laparoscopic ultrasonography showed liver metastases in 10 patients (14%). Specificity and positive predictive value for the laparoscopic technique determining vascular ingrowth were 97% and 92%, respectively, versus 89% and 77% by sonography in patients with normal Doppler findings (difference not statistically significant). Laparoscopic ultrasonography has shown improved detection of hepatic metastases compared to sonography, but it still must prove its value, as compared to noninvasive methods, in local staging.

Adult↗
PubMed1995

Diagnostic laparoscopy combined with laparoscopic ultrasonography in staging of cancer of the pancreatic head region.

The aim of this study was to assess the additional role of diagnostic laparoscopy combined with laparoscopic ultrasonography in the staging of patients with pancreatic head malignancy. Between January 1993 and June 1994, 73 patients with stage I cancer of the pancreatic head determined by preoperative investigation (endoscopic retrograde cholangiopancreatography and Doppler ultrasonography) were eligible for laparoscopic ultrasonography. The peritoneal cavity was investigated for peritoneal deposits, intrahepatic metastases, malignant infiltration of the portal and superior mesenteric vessels, and N3 lymph node metastases. All patients without histologically proven metastases proceeded to laparotomy. Seventy patients were eligible for evaluation. Sixteen of the 21 patients with distant metastases were diagnosed by laparoscopy with ultrasonography. Forty-nine patients had surgical exploration and trial dissection to assess local resectability. Twenty-nine patients (41 per cent) had resectable pancreatic head tumours. The positive predictive value of local ingrowth as determined by laparoscopic sonography was 93 per cent. Laparotomy was avoided in 19 per cent of patients and the preoperative stage was changed in 41 per cent. Laparoscopy including ultrasonography was effective in staging pancreatic head malignancy.

Humans↗
PubMed1995

Laparoscopy and laparoscopic ultrasonography in staging of carcinoma of the esophagus and gastric cardia.

BACKGROUND: The objective of this prospective study was to assess the contribution of laparoscopy combined with laparoscopic ultrasonography (LLU) in the preoperative staging of patients with carcinoma of the esophagus and cardia. STUDY DESIGN: Preoperative LLU was performed in 56 patients who were selected for curative resection of carcinoma of the esophagus (n = 38) or gastric cardia with involvement of the distal esophagus (n = 18) after routine preoperative workup. During LLU, the peritoneal cavity was scrutinized for metastatic disease, and ultrasonography of the liver and celiac axis was performed. In all patients without histologically proven metastases, laparotomy was then performed. RESULTS: The morbidity rate of the procedure was 3.5 percent (two superficial wound infections). In three (5 percent) of the 56 patients, laparotomy was excluded by the presence of intra-abdominal metastases. In three other patients, laparotomy was necessary to confirm the suspected hepatic or peritoneal metastases, or both, because histologic proof was not obtained at laparoscopy. In one patient, LLU failed to detect a small hepatic metastasis in segment VII. The preoperative stage was altered by laparoscopy in nine (17 percent) patients (M1 in six, T4 in three). Laparotomy was avoided in two (11 percent) and the preoperative stage changed in seven patients (41 percent), all of whom had carcinoma of the gastric cardia, as occurred in one (3 percent) and two (6 percent) patients with middle and distal carcinoma of the esophagus, respectively. CONCLUSIONS: Preoperative staging by LLU is of little value in patients with carcinoma of the middle and lower esophagus. The probable role of LLU in the staging of patients with carcinomas of the gastric cardia remains to be confirmed in larger series.

Cardia↗