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T Strate

Publications and source records attributed to T Strate.

17 recordsLinked to original sources
PubMed2005

Effects of isovolaemic haemodilution on oxygenation of liver and skeletal muscle.

BACKGROUND AND OBJECTIVE: Hydroxyethyl starch is frequently used for volume substitution during surgical procedures and for isovolaemic haemodilution. Haemodilution has also been shown to improve tissue oxygen tension in skeletal muscle: However, effects of this volume substitute on tissue oxygen tension of the liver during haemodilution remains unknown. METHODS: Fourteen foxhounds were anaesthetized with fentanyl/midazolam and mechanically ventilated with 30% oxygen. Following splenectomy animals were randomly assigned to a control group without haemodilution but fluid substitution with Ringer's lactate (Group C) or underwent isovolaemic haemodilution to a haematocrit of 25% with hydroxyethyl starch 70/0.5 (Group H). Haemodynamic parameters and oxygen transport during 100 min following isovolaemic haemodilution were measured. Liver oxygen tension was recorded using a flexible polarographic electrode tonometer, whereas in the muscle a polarographic needle probe was used. RESULTS: Animal characteristics and baseline haematocrit were similar in both groups. At baseline the tissue oxygen tension of liver and skeletal muscle were not different between groups. Haemodilution with hydroxyethyl starch 70/0.5 provided augmentation of mean liver tissue oxygen tension (baseline: 46 +/- 13 mmHg; 20 min: 60.3 +/- 12 mmHg; 60 min: 60 +/- 16 mmHg; 100 min: 63 +/- 16 mmHg; P < 0.05 vs. baseline), while oxygen tensions in Group C remained unchanged (baseline: 48 +/- 16 mmHg; 20 min: 52 +/- 19 mmHg; 60 min: 49 +/- 12 mmHg; 100 min: 52 +/- 16 mmHg) and no differences could be detected between groups. Oxygen tension in skeletal muscle changed as follows: Group H - baseline: 24 +/- 32 mmHg; 20 min: 32 +/- 3 mmHg; 60 min: 33 +/- 7 mmHg; 100 min: 33 +/- 11 mmHg. Group C - baseline: 22 +/- 6 mmHg; 20 min: 21 +/- 3 mmHg; 60 min: 24 +/- 4 mmHg; 100 min: 18 +/- 4 mmHg (P < 0.05 vs. baseline, p < 0.05 vs. Group C). CONCLUSION: In this animal model, isovolaemic haemodilution with hydroxyethyl starch 70/0.5 increased tissue oxygen tension in liver and skeletal muscle in comparison with baseline values. However, when compared between groups haemodilution only resulted in an increase of tissue oxygen tension in the muscle but not in the liver.

Anesthetics, Intravenous↗
PubMed2003

Ambulatory long-term pH monitoring in pigs.

BACKGROUND: pH monitoring has been established as the "gold standard" in the diagnosis of gastroesophageal reflux. Evaluation of experimental antireflux therapy should therefore also include this technique, but a suitable technique in an experimental model did not exist so far. The aim of our study was to establish a reliable method for the evaluation of an experimental reflux model in pigs. METHODS: A total of 33 German Landrace pigs with an average body weight of 56 (50.2-67.2) kg were included. pH monitoring was performed before and after open cardiomyotomy in each animal. All manipulations were performed under general anesthesia. After manometric localization of the gastroesophageal high-pressure zone, a standard pH probe was inserted into the pharynx through a small needle-punctured canal on the side of the animal's snout and placed under endoscopic guidance with the proximal sensor 3 cm above the lower esophageal sphincter (LES) and the distal sensor in the stomach for reference. The harness to carry the pH recorder on the animal's back consisted of a modified belly strap that enabled the animal to move around without limitation. For analysis the same threshold levels were defined as in humans. Gastroesophageal reflux was induced by cardiomyotomy. RESULTS: The placement of the standard pH probe was possible in all cases. Inserting the probe on the side of the snout left the animals free to nuzzle, which complies with the normal habits of pigs, without breaking the probes and without being compromised in their natural behavior. Repeated punctures for multiple measurements were easily feasible. We performed up to three examinations in each individual animal. Recording was performed for 48 h. A mean number of 67.3 (+/-9.7) acidic refluxes were registered. The mean number of long acidic refluxes was 3.2 (+/-0.75). For an average total time of 75.5 (+/-14.3) min the pH was below 4 accounting for a fraction time pH below 4 of 3.5% (+/-0.68%). Following cardiomyotomy the number of acidic refluxes increased significantly to 166.1 (+/-21.8) and the number of long refluxes to 17.74 (+/-3.35). The total time of pH below 4 increased to 371.3 (+/-62) min so that the fraction time pH below 4 was 14.5% ( p = 0.0006). CONCLUSION: pH monitoring should be mandatory in any investigation of antireflux therapy. Our method is easy and secure to perform. It is suitable for other gastrointestinal investigations (Bilitec, long-term manometry) that could be carried out using the same technique. The described data represent the basis for other investigations of experimental antireflux therapy.

Animals↗
PubMed2003

Klatskin tumors and Klatskin mimicking lesions of the biliary tree.

AIM: We report on the preoperative capability of imaging modalities and clinical assessment to differentiate between Klatskin tumors and Klatskin mimicking lesions of the biliary tree. Adenocarcinomas of the hepatic ducts (Klatskin tumors) mimic benign fibrosing cholangitis. Extensive resections carry a substantial risk but offer the only chance for cure in patients with a Klatskin tumor. METHODS: Thirty-three consecutive patients who underwent resection for suspicion of a malignant tumor of the hepatic hilum were reviewed. All patients underwent preoperative ultrasonography, computed tomography, ERCP and angiography. The patients were divided into a group of true Klatskin tumors and a group of benign Klatskin mimicking lesions. RESULTS: Twenty-seven of the resected specimens were malignant tumors, and six lesions showed only fibrosing cholangitis. Preoperative clinical presentation and imaging modalities were very similar between Klatskin tumors and fibrosing cholangitis. CONCLUSIONS: Management of obstruction of the liver hilum is dictated by the suspicion of malignancy. Complete removal of the tumor remains the therapeutic aim but clinical presentation and imaging modalities cannot help to differentiate between Klatskin tumors and Klatskin mimicking lesions prior to surgery.

Aged↗
PubMed2002

Chronic pancreatitis: etiology, pathogenesis, diagnosis, and treatment.

BACKGROUND AND AIMS: This review discusses current concepts regarding the etiology, pathogenesis, diagnosis, and treatment of chronic pancreatitis. RESULTS: Treatment of patients suffering from complications of chronic pancreatitis remains a major challenge. Continuous alcohol consumption, a disease with enormous personal and social impact, is still the leading factor in the development of chronic pancreatitis. The most distressing symptom for the patient is pain, which in many instances has already led to a considerable analgesic abuse before a specialist is even consulted. The development of an enlargement of the pancreatic head, the "pacemaker of the disease," parallels pain and potential organ complications such as common bile duct stenosis or portal hypertension. What triggers pancreatic head enlargement is still not known; in particular it is unclear what triggers growth factors to step into action. Pain is most likely due to a combination of hypertension in the organ and parenchymal alterations. Current therapeutic concepts therefore aim at alleviating pain and at management of organ complications while preserving functional tissue to best prevent exocrine and endocrine dysfunction. The ideal procedure thus seems today to be the "customized" pancreatic head resection with additional optional drainage of the pancreatic body and tail.

Chronic Disease↗
PubMed2002

Intractable hiccup: an odd complication after laparoscopic fundoplication for gastroesophageal reflux disease.

Intractable hiccup can be an unbearable circumstance and its treatment is often frustrating. More than 100 causes for hiccup have been described in the literature; the most common cause is gastroesophageal reflux disease (GERD). We report a case of a 31-year-old patient who suffered from intractable hiccup starting 3 weeks after laparoscopic Nissen fundoplication for GERD, a potential surgical complication that has not been described. After frustrating medical treatment, the patient underwent computed tomography and nerve stimulator-guided blockade of vagal and phrenic nerves on each side separately. Hiccup ceased only after blockade of the right phrenic nerve with 4 ml/h l% ropivacaine and relapsed soon after discontinuation. He underwent thoracoscopic right phrenicectomy, which rendered him symptom free for well over 2 months, at the time of this writing.

Adult↗
PubMed2001

Attenuation of sepsis-related immunoparalysis by continuous veno-venous hemofiltration in experimental porcine pancreatitis.

OBJECTIVES: In light of evidence suggesting that hemofiltration favorably influences septic diseases by removing sepsis mediators, the impact of different modalities of continuous veno-venous hemofiltration (CVVH) on outcome and immunologic derangements in porcine pancreatogenic sepsis was evaluated. DESIGN: Randomized, controlled intervention trial. SUBJECTS: Forty-eight minipigs of either sex. INTERVENTIONS: Pancreatitis was induced by intraductal injection of sodium taurocholate (4%, 1 mL/kg body weight [BW]) and enterokinase (2 U/kg BW). Animals were allocated either to untreated controls-group 1-or to one of three treatment groups-group 2: low-volume CVVH (20 mL/kg BW), no change of hemofilters; group 3: low-volume CVVH, filters changed every 12 hrs; and group 4: high-volume CVVH (100 mL/kg BW), filters changed every 12 hrs. Survival represented the major parameter of the study. Serum cytokine levels, sepsis-related down-regulation of major histocompatibility complex II and CD14 expression on leukocytes, bacterial translocation, and endotoxemia were further parameters evaluated in the study. MEASUREMENTS AND MAIN RESULTS: High-volume CVVH combined with periodic filter change was significantly superior compared with less intensive treatment modalities (low-volume CVVH, no filter change) in sepsis protection. Long-term survival (>60 hrs) was found in 67% of group 4 and 33% of group 3 animals (p <.05), whereas in controls and group 2 no animal survived. CVVH ameliorated the initial serum tumor necrosis factor-alpha response and prevented sepsis-induced in vitro endotoxin hyporesponsiveness. Down-regulation of major histocompatibility complex II and CD14 expression on monocytes was significantly improved by CVVH. Improved oxidative burst and phagocytosis capacity in polymorphonuclear leukocytes suggested that leukocyte function was stabilized by CVVH. Also, CVVH significantly reduced bacterial translocation and endotoxemia. CONCLUSIONS: Hemofiltration reversed sepsis-induced immunoparalysis in a porcine model of bile acid-induced pancreatitis. Implications for human pancreatitis must be validated in prospective, clinical protocols.

Acute Disease↗
PubMed2000

Orthotopic liver transplantation for complicated HELLP syndrome. Case report and review of the literature.

A case of hepatic complication in a pregnant woman suffering from HELLP syndrome resulting in the need for transplantation is reported, and an algorithm for those instances is suggested. According to the literature, this is the 5th report of hepatic complications in HELLP syndrome necessitating liver transplantation. Since all but one of the transplanted patients survived (as opposed to a high mortality in non-transplanted patients), it is concluded, that a timely decision for transplantation is a safe option in this high risk group.

Adult↗
PubMed1999

Gastric tonometry accurately predicts mortality in experimental peritonitis in both laparoscopic and conventional surgery.

OBJECTIVES: Tonometry is widely used in the diagnosis of sepsis and splanchnic ischemia. This study was devised to analyze the predictive value of gastric tonometry for outcome of experimental viscus perforation-induced peritonitis. The impact of conventional and laparoscopic intervention on tonometric measurements was the main scope. METHODS: This randomized controlled intervention trial was performed in a University experimental laboratory, using 24 female Duroc pigs. Pigs were subjected to gastric perforation followed by a 12 h interval of peritonitis, and then to either laparoscopic or conventional surgical repair of the defect with peritoneal lavage. Gastric tonometry and cardiocirculatory monitoring were performed. RESULTS: Septic shock associated with peritonitis and subsequent lethal outcome was accurately predicted with gastric tonometry. Changes of gastric mucosal pH correlated significantly with decreases of MAP (r2=0.880; P<0.001) and SVR (r2=0.678; P<0.001), increase of QT (r2=0.486; P=0.013), and mortality (r=0.752; P<0.001). Mortality was significantly higher in laparoscopically treated animals compared to those subjected to the open procedure (78% vs 22%; P<0.045). CONCLUSIONS: Gastric tonometry accurately predicted mortality in experimental peritonitis. The decline of gastric mucosal pH in the laparoscopic group was more than double that of to conventionally treated animals. This finding not only reflected the increase of systemic CO2 due to higher absorption during CO2-pneumoperitoneum, but probably also indicated a more severe form of splanchnic ischemia during laparoscopic surgery. Even though tonometry can be used to accurately predict mortality and separate the high risk group, extreme caution should be applied under conditions associated with severe peritonitis.

Animals↗
PubMed1999

A pneumoperitoneum perpetuates severe damage to the ultrastructural integrity of parietal peritoneum in gastric perforation-induced peritonitis in rats.

BACKGROUND: Minimal invasive surgery is increasingly used in conditions complicated by peritonitis-e.g., peptic ulcer perforation. This study was devised to assess the effect of a pneumoperitoneum (PP) on the ultrastructural integrity of parietal peritoneum in perforation-induced peritonitis. METHODS: Anesthetized rats were subjected either to standardized gastrotomy simulating gastric perforation (groups Ia-d; IIa-d) or to sham perforation (groups IIIa-d, IVa-d). In group I (a-d) and III (a-d), CO2 was insufflated 12 h after gastrotomy for 60 min (Pia 4 mmHg). Glutaraldehyde was administered intraperitoneally at the end of the PP period while the abdominal wall was still extended (group index a), as well as 30 sec (b), 2 h (c), and 12 h (d) after desufflation. Specimens were taken from the parietal peritoneum of the left diaphragm for scanning electronic-microscopic (SEM) analysis. In groups II (a-d) and IV (a-d), simple puncture of the abdominal cavity was performed, and specimens were taken at corresponding times. RESULTS: In group Ia (gastric perforation with PP), distortion of the mesothelial cell layer with concomittant opening of stomata to the submesothelial tissue was already observed in specimens harvested while the abdominal wall was still extended. Concomitantly, scarce microvilli, which appeared coarse and thickened, were lying flat on top of the mesothelial cells. After desufflation (groups Ib-c), a rapid process of mesothelial disintegration with disruption from the submesothelial layer and vanishing of microvilli occurred. At 12 h after PP (group Id), complete deterioration of mesothelial cell integrity was observed. In groups IIa-c (gastric perforation without PP), microvilli appeared shrunk and coarse, while integrity of the mesothelial cell layer remained intact up to 2 h after the abdominal puncture. At 12 h after abdominal puncture (group IId), the microvilli had nearly completely vanished and the mesothelium was breaking apart into multiple soils. CONCLUSIONS: In SEM analysis of parietal peritoneum, premature distortion, and disintegration of the mesothelial cell layer was observed in animals exposed to increased abdominal pressure in addition to gastric perforation-induced peritonitis.

Animals↗
PubMed1999

Hemostasis with the ultrasonically activated scalpel. Effective substitute for electrocautery in surgical patients with pacemakers.

In patients with implanted pacemaker/cardioverter defibrillator (ICD), the use of electrocautery can lead to serious pacemaker dysfunction. The ultrasonically activated scalpel, however, which has been introduced mainly for the use in laparoscopic surgery, could potentially avoid the outlined problem, since no electrical current flows while in use. This hypothesis was tested in a pacemaker patient undergoing laparoscopic cholecystectomy. During the procedure, no abnormal rhythms or ECG interferences were detected while working in close vicinity to the device. Thus, the ultrasonically activated scalpel provides adequate hemostasis and does not bear the risk of pacemaker dysfunction.

Cholecystectomy, Laparoscopic↗
PubMed1998

Laparoscopic vs open repair of gastric perforation and abdominal lavage of associated peritonitis in pigs.

BACKGROUND: Laparoscopy is increasingly used in conditions complicated by peritonitis, e.g., peptic ulcer perforation. Of some theoretical concern is the capnoperitoneum, which may aggravate peritonitis and induce septic shock due to increased intraabdominal pressure and distension of the peritoneum. This animal study was devised to analyze the effectiveness of laparoscopic versus traditional open repair of gastric perforation and abdominal lavage for associated peritonitis. METHODS: To simulate gastric perforation, female Duroc pigs were subjects to standardized gastrotomy. Either 6 or 12 h after gastric perforation, the animals underwent either traditional open or laparoscopic repair of the gastric defect and peritoneal lavage. The subjects were divided into the following four groups: peritonitis for 6 h and open surgery (group I) or laparoscopic surgery (group II); peritonitis for 12 h and open surgery (group III) or laparoscopic surgery (group IV). After an observation period of 6 days, the surviving animals were killed. The main outcome criteria were survival, perioperative changes of hemodynamics suggestive for septic shock, bacteremia, and endotoxemia. RESULTS: There were no significant differences between group I and II. Mortality was 22% in group III, as compared to 78% in group IV (p = 0.045). In group IV, the incidence of perioperative bacteremia and plasma endotoxin concentrations were significantly higher than in group III. Concomitantly, decreased mean arterial pressure and systemic vascular resistance, and increased cardiac output suggested a higher incidence of septic shock in group IV. CONCLUSION: Critical appraisal of laparoscopic surgery is warranted in conditions associated with severe, longstanding peritonitis.

Animals↗
PubMed1998

[Prognostic value of gastric tonometry in peritonitis due to intestinal perforation and laparoscopic versus conventional management in the swine model].

After a 12 hour period of experimental peritonitis induced by gastric perforation mortality was significantly higher in the laparoscopically treated group of pigs when compared to the open procedure. In both groups the treatment was simple oversowing of the defect plus peritoneal lavage. Septic shock associated with peritonitis and subsequent "multi organ failure syndrome" could accurately be predicted with gastric tonometry. In both groups the decline of pHi in septic animals that died was higher than expected.

Animals↗
PubMedDate not supplied

Modifications of the duodenum-preserving pancreatic head resection.

Surgery for chronic pancreatitis has gained wide acceptance because of excellent results regarding pain alleviation and control of complications arising from adjacent organs. After the introduction of the duodenum preserving pancreatic head resection by Beger almost three decades ago, many modifications have been proposed, evaluated and compared. This article reviews the variety of operations, the reported results and potential advantages. Besides the Beger- and Frey procedure, none of the modifications have been properly evaluated in a prospective randomised trial. Both procedures managed to relief the outlined problems while achieving low operative mortality and morbidity. Only the operations according to Beger and Frey can be considered standard procedures in chronic Pancreatitis.

Chronic Disease↗