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Dive into the research topics where Jan Dalenbäck is active.

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Featured researches published by Jan Dalenbäck.


The New England Journal of Medicine | 1996

Atrophic Gastritis and Helicobacter pylori Infection in Patients with Reflux Esophagitis Treated with Omeprazole or Fundoplication

Ernst J. Kuipers; Lars Lundell; Elly C. Klinkenberg-Knol; Niilo Havu; Henk P.M. Festen; Bengt Liedman; C.B.H.W. Lamers; Jan B.M.J. Jansen; Jan Dalenbäck; Pleun Snel; G. Frits Nelis; Stephan G. M. Meuwissen

BACKGROUND Helicobacter pylori infection plays an important part in the development of atrophic gastritis and intestinal metaplasia, conditions that predispose patients gastric cancer. Profound suppression of gastric acid is associated with increased severity of gastritis caused by H. pylori, but it is not known whether acid suppression increases the risk of atrophic gastritis. METHODS We studied patients from two separate cohorts who were being treated for reflux esophagitis: 72 patients treated with fundoplication in Sweden and 105 treated with omeprazole (20 to 40 mg once daily) in the Netherlands. In both cohorts, the patients were followed for an average of five years (range, three to eight). After fundoplication, the patients did not receive acid-suppressive therapy. The presence of H. pylori was assessed at the first visit by histologic evaluation in the fundoplication group and by histologic and serologic evaluation in the omeprazole group. The patients were not treated for H. pylori infection. Before treatment and during follow-up, the patients underwent repeated gastroscopy, with biopsy sampling for histologic evaluation. RESULTS Among the patients treated with fundoplication, atrophic gastritis did not develop in any of the 31 who were infected with H. pylori at base line or the 41 who were not infected; 1 patient infected with H. pylori had atrophic gastritis before treatment that persisted after treatment. Among the patients treated with omeprazole, none of whom had atrophic gastritis at base line, atrophic gastritis developed in 18 of the 59 infected with H. pylori(P<0.001) and 2 of the 46 who were not infected (P=0.62). CONCLUSIONS Patients with reflux esophagitis and H. pylori infection who are treated with omeprazole are at increased risk of atrophic gastritis.


Journal of Gastrointestinal Surgery | 2000

Impact of complete gastric fundus mobilization on outcome after laparoscopic total fundoplication

Anne Blomqvist; Jan Dalenbäck; Cecilia Hagedorn; Hans Lönroth; Anders Hyltander; Lars Lundell

With the objective of further optimizing the outcome of antireflux surgery, we have studied the importance of dividing the short gastric vessels when performing a laparoscopic total fundoplication. Ninetynine consecutive patients with chronic gastroesophageal reflux disease (GERD) were enrolled in the trial. Forty-seven patients (25 men, age 52 ±1.6 years [mean ± standard error]) were randomized to undergo a laparoscopic Nissen-Rossetti total fundic wrap with intact short gastric vessels, whereas 52 patients (29 men, 48 ±1.4 years) had complete division of these vessels. Quality of life was assessed by means of the psychological general well-being and gastrointestinal symptom rating scale indices. The 6- and 12-month follow-up data are reported. Two patients were converted to open surgery. Mobilization of the fundus significantly prolonged the operative time (120 vs. 104 minutes, P = 0.05); otherwise the complication rates were similar in the two groups. Both procedures were equally effective in controlling gastroesophageal reflux at 6 and 12 months’ postoperatively. Division of the short gastric vessels had no significant impact on the point prevalence of postfundoplication complaints at the given follow-up time points. Quality of life was significantly improved by both operative procedures and remained “normal” throughout the followup period. Dividing all short gastric vessels had no impact on the functional outcome during the first year of recovery after a total laparoscopic fundoplication.


Journal of Clinical Investigation | 1996

Sympathetic discharge to mesenteric organs and the liver. Evidence for substantial mesenteric organ norepinephrine spillover.

Anders Aneman; Graeme Eisenhofer; Lars Olbe; Jan Dalenbäck; Peter Nitescu; Lars Fändriks; Peter Friberg

This study using sampling of blood from the portal vein, in addition to arterial and hepatic sites, to estimate separately spillovers of norepinephrine from mesenteric organs and the liver in seven patients undergoing upper abdominal surgery. Conventional measurements in arterial and hepatic venous plasma provided a measure of net hepatomesenteric NE spillover (403 pmol/ml) that indicated a 13% contribution of these organs to total body spillover of NE into systemic plasma (3,071+/-518 pmol/min). The net hepatomesenteric spillover of NE into systemic plasma was much lower than the spillover of NE from mesenteric organs into portal venous plasma (1,684+/-418 pmol/min). This and the hepatic spillover of NE into systemic plasma (212+/-72 pmol/min) indicated a considerable combined spillover of NE from hepatomesenteric organs (1,896+/-455 pmol/min). The sum of the latter estimate with the difference between total body and net hepatomesenteric NE spillovers provided an adjusted total body spillover of NE into both systemic and portal venous plasma (4,564+/-902 pmol/min). Mesenteric organs made a 37% contribution, and the liver made a 5% contribution to the adjusted total body spillover of NE. Thus, a substantial proportion of total body sympathetic outflow is directed towards mesenteric organs; this is obscured by efficient hepatic extraction of NE (86+/-6%) when measurements are restricted to arterial and hepatic venous plasma.


World Journal of Surgery | 1998

Other laparoscopic bariatric procedures

Hans Lönroth; Jan Dalenbäck

Abstract. Laparoscopic surgery is regarded as a major improvement reflected by a rapid recovery and low perioperative and postoperative morbidity. In obese patients the gains of this new technique may be affected by obesity-related problems, such as impaired respiratory function, high intraabdominal pressure, thick abdominal wall, and liver steatosis. This review describes the development of laparoscopic vertical banded gastroplasty (VBG) and gastric bypass procedures; and it addresses questions such as feasibility, comparability to open procedures, procedure-related problems, and recovery. The clinical outcome after laparoscopic VBG and gastric bypass is also updated. Up to May 1997 we have operated on 105 patients with laparoscopic VBG and another 26 completed laparoscopic gastric bypass procedures. The weight loss after both procedures are in accordance with the weight loss seen with open surgery. Procedure-related complications are described in detail in this paper. It is concluded that laparoscopic bariatric surgery will remain an area of importance for clinical practice, research, and development.


Surgical Endoscopy and Other Interventional Techniques | 1998

Laparoscopic or open fundoplication? A complete cost analysis.

Anne Blomqvist; Hans Lönroth; Jan Dalenbäck; Lars Lundell

AbstractBackground: As part of a prospective observational trial, we set out to determine the direct and indirect costs of an open versus a laparoscopic fundoplication for chronic gastroesophageal reflux disease (GERD). Methods: Two groups of patients, each comprising 28 subjects, were studied. Results: All patients received a functioning fundoplication that did not require any additional therapy. Because 19 and 12 patients in the open and laparoscopy groups, respectively, were employed in the work force, we were able to assess the costs due to loss of production. The mean operating time was similar for both groups, but postoperative stay differed significantly; though it amounted to 8 days for the open group, it was only 2 days for the laparoscopy group. Postoperative sick leave was 29.9 days in the open and 9.9 in the laparoscopy group (p < 0.05). The costs of the operations were 18,363 SEK for laparoscopy and 12,856 SEK for conventional fundoplication. On the other hand, the cost for hospital stay amounted to 35,488 SEK in the open group but was only 25,571 SEK for those undergoing laparoscopy. When we add outpatient visits, endoscopies, and other medical expenses, the total direct costs in the laparoscopy group come to 27,693 SEK, as compared to 37,482 SEK for the open fundoplication. The indirect medical costs, which were dominated by loss of production (36,732 versus 12,126 SEK), came to 37,126 and 12,595 SEK in the open and laparoscopy groups, respectively. Conclusions: The total community-based costs for the open and laparoscopic operations for chronic GERD amounted to 74,608 and 40,289 SEK, respectively. Thus, we would recommend the laparoscopic procedure in most cases.


Journal of Gastrointestinal Surgery | 2004

Mechanical consequences of short gastric vessel division at the time of laparoscopic total fundoplication.

Cecilia Engström; Anne Blomqvist; Jan Dalenbäck; Hans Lönroth; Magnus Ruth; Lars Lundell

Laparoscopic Nissen fundoplication is currently the most commonly practiced antireflux operation. Some adverse consequences of the operation remain in the form of mechanical side effects, labeled postfundoplication complaints, of which dysphagia and gas bloat seem to predominate. Measures have been suggested to counteract some of these and one frequently advocated has been division of the short gastric vessels to create a short-floppy wrap. The advantages of this are still debated, particularly in the long-term perspective. The aim of the present study was to evaluate the mechanical consequences of dividing all short gastric vessels at the time of a laparoscopic total fundoplication. Ninety-nine patients with chronic gastroesophageal reflux disease (GERD) were originally allocated on a random basis to have either all short gastric vessels divided or left intact at the time of a laparoscopic total fundoplication. A subsample of these patients, again selected at random, were recruited for a comprehensive manometric investigation 1 year after the operation. In this cohort, 12 patients had all short gastrics divided and in 12 patients, the wrap was done with intact vessels by use of the anterior portion of the fundus. Manometry was carried out by the use of a sleeve sensor to straddle the lower esophageal sphincter (LES), and gastric distension (750 ml air) was used to trigger transient LES relaxations (TLESR). The basal LES tone was similar in the two groups (14.2 ± 2.4 and 18.8 ± 4.3, mean ± SE), respectively. Accordingly, all other relevant manometric variables were equal when the two groups were compared, except for the total number of TLESRs (triggered by gastric distension by air) that were significantly higher (p < 0.02) in patients having their short gastric vessels intact. Consequently, numerically more common cavities were recorded in the latter group. Very similar outcomes in terms of motor function of the LES and esophageal body were observed after a total fundoplication irrespective of whether a complete division of all gastric vessels had been carried out or not. However, after gastric distension with air, more TLESRs were recorded in the latter group suggesting a better maintained ability to vent air from the stomach.


European Journal of Surgery | 2000

Intestinal perfusion during pneumoperitoneum with carbon dioxide, nitrogen, and nitric oxide during laparoscopic surgery

Anders Aneman; Mats Svensson; O. Stenqvist; Jan Dalenbäck; Hans Lönnroth

OBJECTIVE To find out what effect insufflation pressure and type of gas have on intestinal perfusion during pneumoperitoneum. DESIGN Randomized, controlled, prospective, experimental study. SETTING University affiliated animal experimental laboratory, Sweden. ANIMALS Fasted, anaesthetised, domestic pigs of both sexes operated on laparoscopically (n = 7, weight 26-31 kg). INTERVENTIONS Insufflation of carbon dioxide (CO2), nitric oxide (NO), or nitrogen (N2) at intra-abdominal pressures of 0, 5, 10, 15 and 20 mm Hg. MAIN OUTCOME MEASURES Cardiac output, portal blood flow, and jejunal mucosal perfusion. RESULTS Cardiac output decreased during N2 and NO (15, 20 mm Hg) but not during CO2 insufflation because of an accompanying tachycardia. Portal flow decreased during insufflation with N2 and NO (15, 20 mm Hg) and CO2 (20 mm Hg). Jejunal perfusion was reduced during N2 and NO insufflation (5-20 mm Hg) but remained unchanged during CO2 insufflation (5-20 mm Hg). CONCLUSIONS Insufflation with CO2 maintained jejunal mucosal perfusion, probably as a result of hypercarbia as N2 at equal pressures reduced mesenteric flow. The vasodilator NO provided no haemodynamic benefit.


American Journal of Physiology-regulatory Integrative and Comparative Physiology | 1998

Human duodenogastric reflux, retroperistalsis, and MMC

Jan Dalenbäck; Hasse Abrahamson; Einar Björnson; Lars Fändriks; Anna Mattsson; Lars Olbe; Ann-Mari Svennerholm; Henrik Sjövall

The aim of this study was to determine to what extent human migrating motor complex (MMC)-related secretory phenomena are influenced by a recently discovered period of duodenal retroperistalsis during late phase III. A constant-flow perfusion technique was used to measure gastric appearance of acid, bicarbonate, pepsin, bilirubin, IgA, and duodenally infused [14C]polyethylene glycol (PEG) 4000 in 12 healthy volunteers. Interdigestive gastroduodenal motility was recorded by digital manometry. During late antral phase II and III, the gastric lumen was acidified ( P < 0.005 phase III vs. phase I) together with a marked increase in luminal pepsin output (3.1 ± 1.2 during phase III vs. 0.25 ± 0.08 kU/5 min in phase I, P < 0.01), followed by a realkalinization due to a simultaneous reduction of acid secretion and a duodenogastric reflux, aided by retrograde peristalsis, of bicarbonate and IgA but not of bilirubin, at the end of antral phase III ( P < 0.05 phase III vs. phase I values). This physiological duodenoantral reflux phenomenon may play an important role in the chemical and immunological restitution of the antral mucosal barrier function after the exposure to high acid and pepsin concentrations during antral phase III activity.The aim of this study was to determine to what extent human migrating motor complex (MMC)-related secretory phenomena are influenced by a recently discovered period of duodenal retroperistalsis during late phase III. A constant-flow perfusion technique was used to measure gastric appearance of acid, bicarbonate, pepsin, bilirubin, IgA, and duodenally infused [14C]polyethylene glycol (PEG) 4000 in 12 healthy volunteers. Interdigestive gastroduodenal motility was recorded by digital manometry. During late antral phase II and III, the gastric lumen was acidified (P < 0.005 phase III vs. phase I) together with a marked increase in luminal pepsin output (3.1 +/- 1.2 during phase III vs. 0.25 +/- 0.08 kU/5 min in phase I, P < 0.01), followed by a realkalinization due to a simultaneous reduction of acid secretion and a duodenogastric reflux, aided by retrograde peristalsis, of bicarbonate and IgA but not of bilirubin, at the end of antral phase III (P < 0.05 phase III vs. phase I values). This physiological duodenoantral reflux phenomenon may play an important role in the chemical and immunological restitution of the antral mucosal barrier function after the exposure to high acid and pepsin concentrations during antral phase III activity.


Scandinavian Journal of Gastroenterology | 1995

The pH/Pco2 Method for Continuous Determination of Human Gastric Acid and Bicarbonate Secretion A Validation Study

Jan Dalenbäck; Lars Fändriks; L. Olbe; Henrik Sjövall

BACKGROUND The present paper describes and evaluates a methodologic approach for registration of the fast, interdigestive, motility-related changes in gastric acid and bicarbonate outputs seen in man. METHODS The technique is based on continuous gastric luminal perfusion and measurements of pH and PCO2 in gastric effluent and concomitant intragastric/duodenal manometry. Fourteen healthy volunteers participated. RESULTS Direct acid secretory estimations from pH recordings, corrected for hydrogen ion activity, correlated closely with values obtained by conventional titration. After intragastric infusion of bicarbonate, 96 +/- 5% of the newly measured steady-state value was registered virtually instantaneously provided that corrections for the PCO2 electrode time constant and the perfusion/aspiration time were made. In the neutral pH range (pH 5-7), practically full quantitative recovery of intragastrically infused bicarbonate was obtained. In the acid pH interval (pH 2-5) the recovery was significantly lower (53 +/- 6%; p < 0.01). With an aspirate without air admixture and during high perfusion rates (31 and 46 ml/min), full recovery of bicarbonate was obtained also at an acid pH, whereas a reduced perfusion rate (16 ml/min) significantly (p < 0.05) reduced the recovery rate. CONCLUSIONS With the pH/PCO2 technique both acid and bicarbonate assessments have a close to on-line time resolution. Acid output is measured accurately, but the method potentially underestimates actual bicarbonate levels in the acid pH range, a combined effect of diffusion of CO2 into air bubbles in the aspirate and into the gastric mucosa from the lumen. A high gastric perfusion rate minimizes this source of error. The pH/PCO2 technique is well suited for studies of the interaction between secretion and motility in the human stomach.


Scandinavian Journal of Gastroenterology | 1993

Does Antral Distension Inhibit Gastric Acid Secretion or Stimulate Bicarbonate Secretion in ‘Healthy’ Subjects?

A. Hamlet; Jan Dalenbäck; L. Olbe; Lars Fändriks

The effects of a 150-ml antral balloon distension on pentagastrin-stimulated gastric acid secretion and bicarbonate secretion were studied in nine healthy subjects and eight duodenal ulcer (DU) patients. The gastric secretions were simultaneously measured, using a luminal perfusion and pH/PCO2 measurements. Two of the healthy subjects and six of the DU patients were positive for Helicobacter pylori. When H. pylori-positive and -negative subjects were compared, basal gastric acid and bicarbonate outputs did not differ significantly. In H. pylori-infected subjects the bicarbonate transport increased by about 70% on pentagastrin stimulation. In the H. pylori-negative group pentagastrin had no effect on the bicarbonate secretion. Antral distension elicited a 30-35% inhibition of pentagastrin-stimulated gastric acid secretion in the group of H. pylori-negative subjects, whereas the acid secretory level remained essentially unchanged in the positive group. Bicarbonate secretion decreased transiently by the distension in the negative subjects, whereas a slight increase was observed in the infected group. We conclude that antral distension inhibits pentagastrin-stimulated gastric acid output in healthy H. pylori-negative subjects. Our results strongly suggest that the underlying mechanism is a direct inhibition of gastric parietal cell function and not an increased gastric bicarbonate secretion. Furthermore, the results indicate that this defective distension-induced acid inhibition may be correlated to H. pylori infection rather than to duodenal ulcer disease.

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Lars Lundell

Karolinska University Hospital

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Hans Lönroth

University of Gothenburg

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Lars Fändriks

University of Gothenburg

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Anne Blomqvist

Sahlgrenska University Hospital

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L. Olbe

Sahlgrenska University Hospital

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Cecilia Hagedorn

Sahlgrenska University Hospital

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Eva Haglind

Sahlgrenska University Hospital

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Magnus Ruth

Sahlgrenska University Hospital

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