Knut Svanes
University of Bergen
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Thorax | 2010
Cecilie Svanes; Jordi Sunyer; Estel Plana; Shyamali C. Dharmage; Joachim Heinrich; Deborah Jarvis; R. de Marco; Dan Norbäck; Chantal Raherison; Simona Villani; Matthias Wjst; Knut Svanes; J. M. Anto
Background: Early life development may influence subsequent respiratory morbidity. The impact of factors determined in childhood on adult lung function, decline in lung function and chronic obstructive pulmonary disease (COPD) was investigated. Methods: European Community Respiratory Health Survey participants aged 20–45 years randomly selected from general populations in 29 centres underwent spirometry in 1991–3 (n = 13 359) and 9 years later (n = 7738). Associations of early life factors with adult forced expiratory volume in 1 s (FEV1), FEV1 decline and COPD (FEV1/FVC ratio <70% and FEV1 <80% predicted) were analysed with generalised estimating equation models and random effects linear models. Results: Maternal asthma, paternal asthma, childhood asthma, maternal smoking and childhood respiratory infections were significantly associated with lower FEV1 and defined as “childhood disadvantage factors”; 40% had one or more childhood disadvantage factors which were associated with lower FEV1 (men: adjusted difference 95 ml (95% CI 67 to 124); women: adjusted difference 60 ml (95% CI 40 to 80)). FEV1 decreased with increasing number of childhood disadvantage factors (⩾3 factors, men: 274 ml (95% CI 154 to 395), women: 208 ml (95% CI 124 to 292)). Childhood disadvantage was associated with a larger FEV1 decline (1 factor: 2.0 ml (95% CI 0.4 to 3.6) per year; 2 factors: 3.8 ml (95% CI 1.0 to 6.6); ⩾3 factors: 2.2 ml (95% CI −4.8 to 9.2)). COPD increased with increasing childhood disadvantage (1 factor, men: OR 1.7 (95% CI 1.1 to 2.6), women: OR 1.6 (95% CI 1.01 to 2.6); ⩾3 factors, men: OR 6.3 (95% CI 2.4 to 17), women: OR 7.2 (95% CI 2.8 to 19)). These findings were consistent between centres and when subjects with asthma were excluded. Conclusions: People with early life disadvantage have permanently lower lung function, no catch-up with age but a slightly larger decline in lung function and a substantially increased COPD risk. The impact of childhood disadvantage was as large as that of heavy smoking. Increased focus on the early life environment may contribute to the prevention of COPD.
Annals of Surgery | 2004
Bjørg-Tilde Svanes Fevang; Jonas Fevang; Stein Atle Lie; Odd Søreide; Knut Svanes; Asgaut Viste
Aim of Study:The objective of this study was to determine the pattern of recurrence after one or more episodes of adhesive small bowel obstruction (ASBO) during a follow-up period of up to 40 years. Furthermore, we wanted to analyze possible factors with an influence on the recurrence rate and to study the magnitude of “everyday” abdominal pain among these patients. Patients and Methods:Hospital records of 500 patients operated on for adhesive obstruction at Haukeland University Hospital from 1961 to 1995 were studied. The patients were followed until death, loss to follow-up, or end of study (February 2002), with a median follow-up of 10 years and a maximum follow-up time of 40 years. A questionnaire was sent to all living patients to obtain information on recurrences and abdominal complaints. Results:The cumulative recurrence rate for patients operated once for ASBO was 18% after 10 years and 29% at 30 years. For patients admitted several times for ASBO, the relative risk of recurrent ASBO increased with increasing number of prior ASBO episodes. The cumulative recurrence rate reached 81% for patients with 4 or more ASBO admissions. Other factors influencing the recurrence rate were the method of treatment of the last previous ASBO episode (conservative versus surgical) and the number of abdominal operations prior to the initial ASBO operation. Compared to results from the general populations, more ASBO patients suffer from abdominal pain at home. Women and patients having matted adhesions have significantly more complaints about abdominal pain than men and patients with band adhesions. Conclusion:The risk of recurrence increased with increasing number of ASBO episodes. Most recurrent ASBO episodes occur within 5 years after the previous one, but a considerable risk is still present 10 to 20 years after an ASBO episode. Surgical treatment decreased the risk of future admissions for ASBO, but the risk of new surgically treated ASBO episodes was the same regardless of the method of treatment. People treated for ASBO seem to be more prone to experiencing abdominal pain than the normal population, especially those having matted adhesions.
Annals of Surgery | 2000
Bjørg Tilde Svanes Fevang; Jonas Fevang; Lodve Stangeland; Odd Søreide; Knut Svanes; Asgaut Viste
OBJECTIVE To study factors influencing complications and death after operations for small bowel obstruction (SBO) using multifactorial statistical methods. SUMMARY BACKGROUND DATA Death after surgery for SBO is believed to be influenced by factors such as old age, comorbidities, bowel gangrene, and delay in treatment. No studies have been reported in which adverse factors related to death and complications have been systematically investigated with modern statistical methods. METHODS The authors studied retrospectively 877 patients who underwent 1,007 operations for SBO from 1961 to 1995. Patients with paralytic ileus, intussusception, and abdominal cancer were excluded. Odds ratios for death, complications, postoperative hospital stay, and strangulation were calculated by means of logistic regression analyses. RESULTS Death and complication rates decreased during the study period. Old age, comorbidity, nonviable strangulation, and a treatment delay of more than 24 hours were significantly associated with an increased death rate. The rate of nonviable strangulation increased markedly with patient age. Major factors increasing the complication rate were old age, comorbidity, a treatment delay of more than 24 hours, and the need for repeat surgery. CONCLUSION Death and complication rates after SBO decreased from 1961 to 1995. Major factors influencing the rates were age, comorbidity, nonviable strangulation, and treatment delay. Nonviable strangulation was more common in old patients.
Annals of Surgery | 1998
Kjell Øvrebø; Jan Gunnar Hatlebakk; Asgaut Viste; Hans H. Bassøe; Knut Svanes
OBJECTIVE To compare gastric banding (GB) and vertical banded gastroplasty (VBG) with respect to postsurgical gastroesophageal reflux (GER) and to investigate the role of preexisting hiatus hernia. SUMMARY BACKGROUND DATA GB and VBG have for a long time been used in the treatment of morbidly obese patients. The introduction of laparoscopic techniques has renewed the interest in these operations. The long-term results after GB have, however, been poor. VBG was suggested to have antireflux properties because it involves repositioning and retaining the gastroesophageal junction within the abdomen and constructing an elongated intraabdominal tube. METHODS Forty-three morbidly obese patients accepted for GB or VBG were evaluated for GER before and at regular intervals after surgery. All patients were questioned about adverse symptoms and need for antireflux medication. Both before and after surgery, 24-hour pH measurement and upper gastrointestinal endoscopies were performed. RESULTS The prevalence of heartburn and acid regurgitation among patients treated with GB increased from 14% and 13% to 63% and 69%, respectively. Heartburn and acid regurgitation were present before surgery in 32% and 23% of patients treated with VBG, percentages unchanged by the procedure. The 24-hour reflux time increased significantly from 6.4% to 30.9% in patients treated with GB but was essentially unchanged in patients treated with VBG. The prevalence of esophagitis after GB and VBG was 75% and 20%. Acid inhibitors were needed in 81% of patients after GB and 29% of patients after VBG. CONCLUSIONS The prevalence of GER was unchanged by VBG, but VBG did not demonstrate antireflux properties. The incidence of GER increased markedly after GB.
European Journal of Surgery | 2002
B. T. Fevang; D. Jensen; Knut Svanes; Asgaut Viste
OBJECTIVE To evaluate the outcome after initial non-operative treatment in patients with small bowel obstruction (SBO). DESIGN Prospective study. SETTING University hospital, Norway. PATIENTS One hundred and fifty-four patients with 166 episodes of SBO admitted during the period (1994-1995). Patients younger than 10 years as well as patients with large bowel obstruction, paralytic ileus, incarcerated hernia or SBO caused by cancer were excluded from the study. INTERVENTIONS Patients with signs of strangulation were operated on early. The rest were given a trial of conservative treatment. MAIN OUTCOME MEASURES Need of operative treatment. Incidence of bowel strangulation, complications and death. RESULTS There were 166 cases of SBO. Twenty patients were operated on early among whom bowel was strangulated in 9. Among the 146 patients initially treated conservatively 93 (64%) settled without operation, 9 (6%) had strangulated bowel and 3 (2%) died. Of the 91 patients with partial obstruction but no sign of strangulation, 72 (79%) resolved on conservative treatment. CONCLUSIONS Patients with partial obstruction with no sign of strangulation should initially be treated conservatively. When complete obstruction is present, it may settle on conservative management, but the use of supplementary diagnostic tools might be desirable to find the patients who will need early operative treatment.
Annals of Surgery | 1994
Cecilie Svanes; Rolv T. Lie; Knut Svanes; Stein Atle Lie; Odd Søreide
ObjectiveThe authors assessed the consequences of delayed treatment for ulcer perforation with regard to short-term and long-term survival, complication rates, and length of hospital stay. Summary Background DataImportant adverse effects of delayed treatment have not been studied previously. Conflicting results have been given with regard to short-term survival. MethodsOne thousand two hundred ninety-two patients operated on for perforated peptic ulcer in the Bergen area between 1935 and 1990 were studied. The effect of delay on postoperative lethality and complications adjusted for age, sex, ulcer site, and year of perforation was analyzed by stepwise logistic regression. The effect of delay on duration of hospital stay adjusted for potential confounding factors was analyzed by Cox proportional hazards regression. Observed survival was estimated by the Kaplan-Meier method, and expected survival was calculated from population mortality data. ResultsAdverse effects increased markedly when delay exceeded 12 hours. Delay of more than 24 hours increased lethality sevenfold to eightfold, complication rate to threefold, and length of hospital stay to twofold, compared with delay of 6 hours or less. The reduced long-term survival for patients treated more than 12 hours after perforation could be attributed entirely to high postoperative mortality. ConclusionsDelayed treatment after peptic ulcer perforation reduced survival, increased complication rates, and caused prolonged hospital stay. To improve outcome after ulcer perforation, an effort should be made to keep delay at less 12 hours, particularly in elderly patients.
Gut | 1993
Cecilie Svanes; H Salvesen; Lodve Stangeland; Knut Svanes; Odd Søreide
Perforated gastroduodenal ulcer was studied in 1483 patients in the Bergen area during the years 1935-90 to discover time trends in age and sex, disease characteristics, treatment, and outcome. The male:female ratio fell from 10:1 to 1.5:1, median age increased from 41 to 62 years. Most perforations were found in the duodenum in 1935-64, and in the pyloric and praepyloric area in 1965-90. There was a 10% occurrence of gastric ulcers throughout the study period. Ulcer site was related to age (more gastric and less duodenal perforations with increasing age) and sex (more pyloric and less duodenal ulcers among women). There were twice as many perforations in the evening compared with the early morning. The diurnal variation was more pronounced for duodenal and pyloric than for gastric and praepyloric perforations. Circadian and seasonal variation of ulcer perforation did not change during the 56 years studied. Treatment delay increased from median five hours to median nine hours. Infective complications and mortality fell with the introduction of antibiotics around 1950. General complications has increased in recent years because of the increase of elderly patients. Among patients who died, the proportion with associated disease rose from 27 to 85% during the study period.
European Journal of Surgery | 2000
B. T. Fevang; D. Jensen; J. Fevang; Karl Søndenaa; Kjell Øvrebø; Ola Røkke; H. Gislasson; Knut Svanes; Asgaut Viste
OBJECTIVE To find out whether contrast radiography helps to resolve small bowel obstruction. DESIGN Prospective randomised trial. SETTING University hospital, Norway. SUBJECTS 98 consecutive patients with symptoms of small bowel obstruction and a plain abdominal radiograph that confirmed the diagnosis. INTERVENTIONS The patients were randomly allocated to receive a mixture of barium and sodium diatrizoate (Gastrografin) (n = 48) or not (n = 50). Both groups were followed up clinically and by repeated abdominal films. MAIN OUTCOME MEASURES Non-operative resolution of small bowel obstruction; number of patients with strangulated bowel; bowel resections; mortality; complications; hospital stay; and time from admission to operation. RESULTS No significant differences were observed between the groups in the incidence of non-operative resolution (31/48 in contrast group, 35/50 in control group, OR: 0.89), strangulation obstruction (1/48 in contrast group, 4/50 in control group, OR: 0.24), bowel resection (3/48 in contrast group, 4/50 in control group, OR: 0.76), complications (8/48 in contrast group, 5/50 in control group, OR: 1.80), mortality (3/48 in contrast group, 1/50 in control group, OR: 3.26), and hospital stay (0-7 days: 34/48 in contrast group, 38/50 in control group, p = 0.95). The contrast group had a shorter interval between admission and operation than the control group (0-24 hours: 12/48 in contrast group, 3/50 in control group, p = 0.005). CONCLUSION The contrast examination did not contribute to the resolution of small bowel obstruction.
European Surgical Research | 1991
S. Dabrowiecki; Knut Svanes; Jon Lekven; Ketil Grong
The purpose of the present work was to study the tissue reaction to polypropylene mesh (Marlex) implanted in three different layers of the abdominal wall, comparable to common clinical practices. The reaction to mesh was compared in terms of tissue oedema, blood flow, and histological appearance in rats. When mesh was placed between muscle layers, blood flow in the abdominal wall was high during the first 4 days after implantation but similar to flow in nonoperated rats 14 and 140 days after implantation. When mesh was placed under skin or on the peritoneum, there was no hyperaemia early after implantation, and flow rate was clearly lower than in non-operated controls 140 days after implantation. The operative procedure produced increased tissue water content, declining from the 1st to the 14th day after operation. Mesh induced additional oedema in adjacent muscle tissue irrespective of localization of the implant (p less than 0.01, vs. sham). Except when separated by peritoneum, mesh caused hyperaemia in muscle tissue in direct contact with mesh the 1st and the 4th day after implantation. After 14 and 140 days no mesh-induced hyperaemia was present. The inflammatory response to mesh was similar in the peritoneum and between muscles, less pronounced in the subcutis. It was characterized by the accumulation of macrophages and the formation of inflammatory granulation tissue in the subacute phase, later followed by the formation of fibrous tissue around mesh fibres. This study suggests that mesh implants should be placed in apposition to muscles in order to obtain well-vascularized healing.
Surgical Endoscopy and Other Interventional Techniques | 2001
F. F. Gudmundsson; H. G. Gislason; Aly Dicko; Arild Horn; Asgaut Viste; Ketil Grong; Knut Svanes
BackgroundThe aim of the study was to investigate the effects of prolonged intra-abdominal pressure on systemic hemodynamics and gastrointestinal blood circulation.MethodsThe intra-abdominal pressure in anesthetized pigs was elevated to 20 mmHg (7 animals), 30 mmHg (7 animals), and 40 mmHg (4 animals), respectively. These pressures were maintained for 3 h by intra-abdominal infusion of Ringer’s solution. A control group of seven animals had normal intra-abdominal pressure (IAP). Transit time flowmetry and colored microspheres were used to measure blood flow.ResultsAn IAP of 20 mmHg did not cause significant changes in systemic hemodynamics or tissue blood flow. An IAP of 30 mmHg caused reduced blood flow in the portal vein, gastric mucosa, small bowel mucosa, pancreas, spleen, and liver. Serum lactate increased in animals with an IAP of 30 mmHg, but microscopy did not disclose mucosal damage in the stomach or small bowel. An IAP of 40 mmHg was followed by severe circulatory changes.ConclusionsProlonged IAP at 20 mmHg did not cause changes in general hemodynamics or gastrointestinal blood flow. Prolonged IAP at 30 mmHg caused reduced portal venous blood flow and reduced tissue flow in various abdominal organs, but no mucosal injury. A prolonged IAP of 40 mmHg represented a dangerous trauma to the animals.