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O Mathisen

Publications and source records attributed to O Mathisen.

At least 19 recordsLinked to original sources
PubMed2002

A comparative study of the short-term outcome following open and laparoscopic liver resection of colorectal metastases.

BACKGROUND: Laparoscopic resection of liver tumors is feasible, but few studies have compared short-term outcome of the laparoscopic approach to that of a conventional technique. METHODS: Eighteen tumor resections performed during 14 procedures (14 patients) by conventional surgery were compared to 21 similar resections performed laparoscopically during 15 procedures (13 patients). All patients had colorectal liver metastases. RESULTS: No perioperative mortality occurred. Surgical time, peroperative bleeding and blood transfusion requirement were similar in the two groups. The resection margin was involved by tumor tissue in one specimen laparoscopically resected and in two specimens conventionally resected (p = 0.58). Patients operated laparoscopically remained in hospital for median 4 days, while patients operated conventionally stayed median 8.5 days (p <0.001). Patients operated laparoscopically required less opioid medication than patients having conventional surgery (median 1 vs 5 days; p = 0.001). CONCLUSIONS: Short-term outcome of laparoscopic liver resection compares to that of conventional surgery, with the additional benefits derived from minimal invasive therapy.

Adult↗
PubMed2002

Laparoscopic cholecystectomy: bile duct and vascular injuries: management and outcome.

BACKGROUND: This is a retrospective study of 32 consecutive patients referred in the period 1992-2000 for management of serious bile duct injuries caused by elective laparoscopic cholecystectomy. METHODS: The patients were referred on median 29 days (0 days to 34 months). Only 7 patients were referred immediately after discovery of the injury. At the local hospital, 25 patients underwent various procedures in attempts at repair. Ten of the patients were treated for bile duct strictures after previous repairs in other hospitals. RESULTS: At referral, 23 patients (72%) had complete transection of the bile duct, while 9 had bile leakage injuries. Additional complications were occlusion of the right hepatic artery in 8 patients (24%) and occlusion of the mesenteric superior artery in 1 patient. Infectious complications were prominent in 21 patients (70%), 6 of whom had septicaemia. Operative management with hepaticojejunostomy Roux-Y was employed in 22 patients. Various non-operative strategies were chosen, including endoscopically or transhepatic stenting of the bile duct and embolization of the right hepatic artery. There was no difference in hospital stay between operative and non-operative procedures which on median was 16 days ( range 7-69 days). Three patients died: one had thrombosis of the superior mesenteric artery, while the other two died of complications to bile peritonitis. Median observation period is 5 years (5 months to 8 years). Two patients have cholangitis; both had injury to the right hepatic artery. The other patients all had normal ultrasonograms of the liver and normal/almost normal liver function tests. CONCLUSIONS: Bile duct injuries continue to occur, are serious and may result in death. Injury to the right hepatic artery is present in many cases. Patients are referred late to a competent center, resulting in serious infection in 70%.

Adolescent↗
PubMed2001

Magnetic-resonance-guided percutaneous cryoablation of hepatic tumours.

OBJECTIVE: To study the feasibility of percutaneous cryoablation of hepatic tumours monitored by magnetic resonance imaging (MRI). DESIGN: Prospective study SETTING: University hospital, Norway PATIENTS: Six patients with hepatic metastases from colorectal cancer. INTERVENTIONS: Percutaneous cryoprobe positioning under general anaesthesia. Positioning and freezing monitored by near-real-time MRI using an open 0.5 Tesla MRI configuration system. MAIN OUTCOME MEASURES: Safety and feasibility of the procedure. Measurement of volumes of cryolesions. RESULTS: One patient developed a biliary leakage that had to be drained. Four patients developed pleural fluid. Two small tumours were adequately cryoablated. In the remaining 4 patients with large (>4 cm) tumours, an adequate cryolesion could not be formed. Cryolesion volumes larger than 105 cm3 were not produced even using 3-4 probes. MRI visualised the growing cryolesion well, but positioning of the cryoprobes was time-consuming. CONCLUSION: MR guided cryoablation is clinically feasible and gives good visualisation of the procedure. Patients with small tumours (<3 cm) seem to be best suited to this percutaneous approach as cryolesion volumes claimed to be adequate for tumour destruction can be produced. Measurement of tumour volume preoperatively may help to select patients who will respond.

Aged↗
PubMed2001

Veno-venous bypass in liver transplantation: heparin-coated perfusion circuits reduce the activation of humoral defense systems in an in vitro model.

We studied the effects of bypass circuit surface heparinization on kallikrein-kinin, coagulation, fibrinolytic and complement activation in a closed model system for simulating veno-venous bypass (WBP) in orthotopic liver transplantation (OLT). The circuits were identical to those in routine use during clinical OLT in our institution. Fresh whole human blood diluted 1:2 with Ringer's acetate was circulated at a non-pulsatile flow (2 l/min) and at a constant temperature (37.5 degrees C) for 12 h. In 10 experiments, the entire inner surface of the circuits was coated with end-point attached heparin (HC). In the remaining 10, non-treated PVC tubing was used (NC). Components of the plasma kallikrein-kinin, coagulation, fibrinolytic and complement systems were analyzed using functional techniques (chromogenic peptide substrate assays) and enzyme immunoassays at baseline, 3 and 12 h. Significant activation of the initial (C3bc) and terminal (TCC) components of the complement system were found in both the NC and HC groups after 3 and 12 h: C3bc: NC: baseline = 4 (3.5-7.7), 3 h = 17.3* (12.5-27), 12h = 31* (17.7-63.6), HC: baseline = 4.9 (3.2-6.8), 3h = 9* (6-14.4), 12h = 13.7* (7.4-18.1). TCC: NC: baseline = 0.4 (0.2-0.6), 3h = 5*(0.8-11.9), 12 h: 13.1* (4.2-25.7). HC: baseline = 0.5 (0.1-0.6), 3 h = 0.6* (0.1-0.8), 12 h = 1.2* (0.3-2) AU/ml; median and range (*: p < 0.05). The C3bc and TCC concentrations were significantly higher in the NC group at 3 and 12 h, compared to the HC group: C3bc (NC vs. HC group): 3 h, p < 0.001; 12 h, p < 0.001. TCC (NC vs. HC group): 3h, p < 0.001; 12 h, p < 0.001. Significant increases in the values of thrombin-antithrombin complexes (p = 0.003), prothrombin fragment 1 + 2 (p = 0.006) and plasmin-alpha2-antiplasmin complexes (p = 0.016) were found in the non-coated group, but not in the heparin-coated group during the observation period, showing that the coagulation and fibrinolytic systems were activated in the non-coated circuits. We conclude that heparin-coating of the internal surface of the extracorporeal perfusion circuit used for WBP reduces activation of the plasma cascade systems in a closed venous system in vitro.

Blood Coagulation Factors↗
PubMed1999

Plasma proteolytic activity in liver transplant rejection.

In this study, we evaluated the role of proteolytic enzymes belonging to the coagulation, fibrinolytic, and plasma contact systems in the early postoperative phase after orthotopic liver transplantation (OLT). Twenty-nine patients were studied at the time of OLT and during the first 2 postoperative weeks. Blood samples were collected daily after OLT and analyzed for kallikrein-like activity (KK), functional kallikrein inhibition (KKI), plasmin-like activity (PL), and alpha2-antiplasmin (AP). In addition, prekallikrein (PKK), prothrombin (PTH), antithrombin III (AT III), plasminogen (PLG), prothrombin/antithrombin III complexes (TAT), prothrombin fragment 1 + 2 (F1 + 2), and plasmin/alpha2-antiplasmin complexes (PAP) were measured. Nineteen patients experienced biopsy-verified acute rejections (AR) and ten patients had uneventful courses and served as controls. Plasma analyses showed that the contact, coagulation, and fibrinolytic systems were activated during OLT. Following OLT, continuous thrombin and plasmin generation was observed, and these effects were more pronounced in the group having an uneventful course than in patients with AR. Factors that could possibly affect plasma proteolytic activity, such as blood product usage during and after OLT and cold ischemia time of the liver graft, did not differ between the groups, nor did the routine liver function tests, alanine aminotransferase (ALT) and aspartate aminotransferase (AST).

Adolescent↗
PubMed1997

Percutaneous technique for venovenous bypass including a heat exchanger is safe and reliable in liver transplantation.

We have introduced and evaluated several modifications of the conventional venovenous bypass (VVBP) in 29 adult patients undergoing liver transplantation (OLT). A percutaneous technique for insertion of a jugular venous return cannula and a femoral vein cannula was applied. The inferior mesenteric vein (IMV) was used for splanchnic decompression, which facilitated dissection of the recipient liver and allowed portal anastomosis to be performed without disconnecting the portal bypass. A heat exchanger was introduced into the bypass circuit to prevent heat loss. The percutaneous technique prevented complications related to dissection in the axilla and groin. Hemodynamic characteristics corresponded to those found using the traditional technique. Complications related to the VVBP were seen in only one patient in whom the femoral catheter was accidentally introduced into the femoral artery. We conclude that percutaneous cannulas, use of the IMV for splanchnic decompression and the introduction of a heat exchanger offer significant benefits and that they are safe and reliable.

Adult↗
PubMed1996

[Liver transplantation in Norway. Results after 10 years and 114 transplantations].

A total of 114 liver transplantations were performed in 106 patients in Norway during 1984-1994. Survival after one year was 65% and after three years 57%. The most frequent causes of death were infections and rejections. The survival rate improved considerably during the period, and after 1990 the 1 year survival was 70%. Approximately 2/3 of the patients return to work or education. Very few patients die later than 12 months after the transplantation. The most frequent indications were primary biliary cirrhosis, metabolic liver disease, primary sclerosing cholangitis, autoimmune cirrhosis and fulminant liver failure. The number of liver transplantations (approximately 4 per million inhabitants) is lower in Norway than in the other Nordic countries. The number should be increased to 7-8 per million inhabitants.

Adolescent↗
PubMed1995

Activation of the plasma contact system and hemodynamic changes after graft revascularization in liver transplantation.

In this study, the relation between activation of the plasma contact system and hemodynamic changes during orthotopic liver transplantation was evaluated. Nineteen consecutive courses of OLT in 17 adult patients were investigated. Veno-venous bypass was used in all patients. Blood samples were drawn through all phases of the procedure, and analyzed for the following parameters using functional techniques (chromogenic peptide substrate assays): plasma kallikrein (KK), prekallikrein, functional plasma kallikrein inhibition, C1 inhibitor, and alpha 2-macroglobulin. Plasma high molecular weight kininogen (HK) degradation was evaluated using the immunoblotting technique. An abrupt rise in KK activities occurred within 1 min after portal reperfusion of the liver graft (7-16 U/L, P < 0.05). Simultaneously, proteolytic breakdown of HK was seen. The elevated KK activities were maintained the next 1 1/2 hr. Ten min after graft reperfusion, a significant increase in cardiac output compared with the anhepatic phase (7.2-12.4 L/min, P < 0.05) was found. At the same time, systemic vascular resistance fell significantly (817-408 dynes x sec/cm-5, P < 0.05). The increase in plasma KK activities accompanied by simultaneous degradation of HK seen immediately after reperfusion of the liver graft may be due to contact activation as recipient blood contacts with the underlying basement membrane of injured sinusoidal endothelium in the transplanted liver. We suggest that hemodynamic changes associated with the postreperfusion syndrome seen after revascularization of the liver in OLT could at least be caused in part by bradykinin release due to contact activation.

Adult↗
PubMed1995

Risk factors associated with mortality and morbidity after elective splenectomy.

OBJECTIVE: To assess the effect of certain risk factors on the outcome of elective splenectomy. DESIGN: Retrospective cohort study. SETTING: University hospital, Norway. SUBJECTS: 135 patients who underwent elective splenectomy from 1978 to 1992 for autoimmune diseases (n = 58), myeloproliferative disorders (n = 58), and other diagnoses (n = 19). MAIN OUTCOME MEASURES: Morbidity and mortality, and the effect on outcome of age, malignancy, platelet count, treatment with steroids, and blood transfusion during the operative period. RESULTS: Three patients died, one from each diagnostic group; all had been treated with steroids. The overall complication rate was 31% (42/135). Most of the complications (31, 74%) were infective (pneumonia n = 23, abscess or sepsis n = 8). Nine patients required reoperation (haemorrhage, n = 6, and wound dehiscence, n = 2, and bowel obstruction, n = 1). Neither treatment with steroids nor severe thrombocytopaenia were risk factors for any complication, but age (p = 0.05) and a diagnosis of myeloproliferative disease (p = 0.08) had an important though not significant role. Blood transfusion during the operative period was the only independent risk factor (p = 0.001), and further analysis showed that transfusion of blood had a dose dependent effect on the incidence of infective complications (chi-square for linear trend 14.21 p < 0.001). CONCLUSION: To reduce the complication rate of elective splenectomy blood transfusion during the operative period should be avoided.

Adolescent↗
PubMed1993

Radiology of the ileal J-pouch-anal anastomosis (IPAA).

Forty-four consecutive patients operated on with ileal J-pouch-anal anastomosis (IPAA) and diverting ileostomy were examined with barium contrast medium of the pouch before closure of the ileostomy. CT was performed in 4 of the patients. The anatomy of the ileal reservoir as well as complications were assessed. As normal postoperative anatomy we found a "blind loop" at the upper part of the reservoir in 29 patients and a contrast lucency at the anastomosis between the anal channel and the pouch in 5 patients. Complications were revealed at barium contrast medium examinations in 13 patients, including stenoses at the anastomosis between the pouch and the anal channel in 8 patients and fistulas in 5 patients. CT was especially valuable in the exact diagnosis and location of a pelvic abscess in 3 patients, none of which was shown at pouchography.

Adolescent↗
PubMed1992

[Natural products can be hazardous to health].

Side effects of herbal and health food products have been infrequently reported such as hepatic damage after use of such products. Four such patients were treated in our department in the course of two years. In all four patients, the use of herbal remedies was the probable cause of serious hepatic damage, but both etiology and pathogenesis were difficult to establish. Two major areas of concern are inaccurate formulation and contaminated preparations. As long as no therapeutic effect can be demonstrated from this type of medicine, serious side effects are unacceptable. A critical attitude should be adopted towards these medicines and the use of them.

Adult↗
PubMed1991

Hepatic and splanchnic metabolism of plasma proteolytic enzymes before, during, and after clamping of the hepatic artery and portal vein.

Parameters of the kallikrein-kinin, fibrinolytic, and coagulation systems before (control), during, and after occlusion of the hepatic artery and the portal vein were studied in anesthetized pigs. Hepatic synthesis was observed for kallikrein, plasmin, and plasminogen. The other factors, prekallikrein, kallikrein inhibitor, alpha 2-antiplasmin, prothrombin, and antithrombin-III were all released by the liver and underwent partial hepatic inactivation. The splanchnic area showed a significant synthesis of antithrombin-III. After 90 min of hepatic arterial occlusion, the hepatic release of all factors declined, and synthesis of kallikrein, plasmin, and plasminogen fell an average of 54%. The inactivation of prekallikrein and alpha 2-antiplasmin was increased and the splanchnic synthesis of antithrombin-III fell. Portal vein blood flow fell by 38%. After 15 min of portal vein occlusion (combined occlusion of the hepatic artery and portal vein) the splanchnic area started to synthetize kallikrein and the hepatic inflow of kallikrein increased by more than 50%. Splanchnic metabolism of other factors was also altered, but after revascularization of the hepatic artery changes were mostly insignificant. Hepatic synthesis of kallikrein and plasmin remained depressed after reperfusion, and that of plasminogen fell to zero. After this short period of occlusion of the hepatic artery and portal vein, plasma concentrations of prekallikrein, plasmin, and alpha 2-antiplasmin were decreased, causing a state of fibrinolysis. A role for kallikrein/bradykinin in hepatic blood flow regulation is proposed and implications of these observations for liver transplantation are discussed.

Animals↗
PubMed1991

Mechanism of ursodeoxycholic acid- and canrenoate-induced biliary bicarbonate secretion and the effect on glucose- and amino acid-induced cholestasis.

The mechanism of ursodeoxycholic acid (UDCA)- and canrenoate-induced bicarbonate choleresis was studied before and during the administration of glucose or amino acids in anaesthetized pigs. Previous studies have shown that the canalicular secretion has, on a molar basis, a relationship among the secretion of chloride, bicarbonate, and bile acids of 0.9, 0.3, and 1, respectively. Ductular secretion is associated with the transport of 0.25 mol chloride per 1 mol bicarbonate. In control experiments UDCA was associated with a biliary secretion of about 1.3 mol chloride and 0.5 mol bicarbonate per 1 mol bile acid, and canrenoate caused the secretion of 1.2 mol chloride per 1 mol bicarbonate. Intravenous infusion of glucose or amino acids increased these relationships, and after administration of UDCA or canrenoate, these relationships were still increased by at least 70% on average when compared with the control experiments. A reduction in bile secretion after glucose or amino acid infusion is opposed by UDCA or canrenoate. The effect of UDCA or canrenoate on bile secretion is not disturbed by glucose or amino acids. Both substances stimulate canalicular bicarbonate secretion and could be of importance in improving cholestatic conditions.

Amino Acids↗
PubMed1991

Effect of phlorizin on hepatic bile production before and during glucose infusion.

During intravenous infusion of glucose, bile secretion is reduced (cholestasis), indicating that hepatocellular metabolism of glucose could have harmful effects on the liver. Phlorizin has been identified as a compound capable of impeding glucose uptake of liver cells. To examine whether phlorizin had any effect on glucose-associated cholestasis, three groups of experiments were performed on anaesthetized pigs. In group I phlorizin (100 mg/kg body wt) during normoglycaemia stimulated bicarbonate-dependent bile secretion by 56 +/- 4%. After phlorizin, hyperglycaemia decreased both bile acid- and bicarbonate-dependent bile secretion by 37 +/- 4%. But after the glucose load normalization of plasma glucose concentration increased the bicarbonate-dependent fraction by 38 +/- 4%. In group II phlorizin (100 mg/kg body wt, infused intravenously) during hyperglycaemia stimulated bicarbonate-dependent bile secretion by 35 +/- 5%. In group III bile secretion was continuously stimulated by infusion of Na-taurocholate. Hyperglycaemia reduced bicarbonate-dependent bile secretion by 33 +/- 4%, but after phlorizin both bile acid- and bicarbonate-dependent bile secretion increased on average by 121 +/- 8%. The osmotic effect of hyperglycaemia cannot be blocked by phlorizin, but judged by the effect on bile secretion, phlorizin may decrease the cholestatic effect induced by metabolism of glucose. Phlorizin could be an interesting compound for use in solutions for organ preservation.

Animals↗
PubMed1991

Effect of insulin on hepatic bile secretion during normoglycaemia and hyperglycaemia.

The roles of hyperosmolality, hyperglycaemia, and insulin in glucose-induced reduction of bile secretion were examined in anaesthetized pigs. Compared with normoglycaemia, intravenous infusion of isotonic glucose reduced bile acid-dependent bile secretion at a plasma glucose concentration of 18 mmol/l, with 34 +/- 4%. Lowering of plasma glucose concentration to normoglycaemia after administration of insulin (10 U/kg body wt. low dose) increased bicarbonate-dependent bile secretion by 23 +/- 3%. Induction of hyperglycaemia (plasma glucose concentration, 16 mmol/l) and the combined infusion of isotonic glucose and the low insulin dose decreased bile secretion by 22 +/- 3%. During hyperglycaemia (plasma glucose concentration, 16 mmol/l) the combined infusion of isotonic glucose and a high dose of insulin (60 U/kg body wt) increased bile acid-dependent bile secretion by 26 +/- 3%. Hyperglycaemia reduces bile secretion without altering plasma osmolality. Endogenous production (or too rapid degradation) of insulin may be too small during intravenous glucose infusion to cope with the metabolic demands of hepatocellular glucose conversion. This may be overcome by administration of insulin in a large dose, which stimulates bile acid secretion.

Animals↗
PubMed1991

Perivascular low attenuation zone at CT of liver transplants. A follow-up study.

A follow-up study of 30 liver transplant patients confirmed that periportal and pericaval rims of low attenuation found at CT reflect hepatic lymph stasis. The perivascular rims are found coexistent with acute allograft rejection, but are not correlated with acute rejection, immunosuppressive agents (cyclosporin A), or intercurrent infection. Disappearance of the perivascular low attenuation zone in our material coincided with normalization of liver biochemistry probably associated with reestablishment of lymphatic drainage. Like previous reports on experimental hepatic lymph stasis, our study thus indicates that lymph stasis may have harmful effects on human liver allografts.

Adolescent↗
PubMed1990

Dose-dependent effects of glycine, alanine, and glucose on hepatic bile secretion, oxygen consumption, and hemodynamics.

To assess the effects of a small (0.5%) and a large dose (5%) of glycine and alanine and of hypertonic glucose on hepatic bile secretion, oxygen consumption, and hemodynamics, experiments were performed on anesthetized pigs. Only the large dose of amino acids exerted significant changes. Glycine, alanine, and glucose reduced bile acid-dependent bile secretion gradually, which was nearly halved from a control value of 0.32 +/- 0.04 ml/min. Oxygen consumption was thereby continuously stimulated during amino acid and glucose infusion and increased from 448 +/- 132 mumol/min before to 995 +/- 226 mumol/min after the infusion of glycine, alanine, and glucose. Hepatic arterial blood flow increased from 214 +/- 14 ml/min to 238 +/- 14 ml/min after glycine infusion, whereas portal venous blood flow decreased from 542 +/- 50 ml/min to 481 +/- 47 ml/min. Total hepatic blood flow remained unchanged. Alanine and glucose provoked no further changes in hepatic blood flow. Bile secretion is a sensitive marker of hepatic metabolism, whereas hepatic blood flow is not a dominant regulator of bile secretion. Stimulation of hepatic metabolism is not followed by changes in total hepatic blood flow.

Alanine↗