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H Sitter

Publications and source records attributed to H Sitter.

At least 73 records · Page 4Linked to original sources
PubMed1994

Parathyroid function following ligation of the inferior thyroid arteries during bilateral subtotal thyroidectomy.

A randomized controlled trial was performed to compare two techniques of bilateral subtotal thyroidectomy for non-toxic nodular goitre with regard to postoperative parathyroid function. The 50 patients in group 1 underwent ligation of the trunks of the inferior thyroid arteries. In group 2 (50 patients) the branches of these arteries were suture-ligated at the thyroid capsule. Total calcium, ionized calcium and parathyroid hormone levels were determined before operation, and 6, 24 and 72 h after surgery. Ninety-one patients were seen at follow-up 5-10 months after operation. Ten patients in group 1 and 12 in group 2 required calcium and/or vitamin D supplementation for symptomatic hypocalcaemia in the immediate postoperative period. At follow-up only one patient in each group had mild hypoparathyroidism. No statistically significant differences were found between groups regarding total calcium, ionized calcium and parathyroid hormone levels. Truncal ligation of the inferior thyroid arteries during bilateral subtotal thyroidectomy does not cause hypoparathyroidism or hypocalcaemia.

Calcium↗
PubMed1994

Granulocyte colony-stimulating factor prophylaxis before operation protects against lethal consequences of postoperative peritonitis.

BACKGROUND: Postoperative peritonitis has a high mortality in human beings. It is accepted that cytokines are important mediators in pathophysiology of sepsis. The recent failure of clinical trials increased the necessity to proof new drugs in more clinically relevant animal models. The aim of this study was to examine the effect of granulocyte colony-stimulating factor (G-CSF) in addition to an antibiotic in postoperative peritonitis. METHODS: Dose-response curves and experimental conditions were developed in a total of 295 rats. The main experiment included three groups: control animals receiving a fecal inoculum, a group treated with antibiotic, and a third group receiving G-CSF in addition to the antibiotic. The main outcome was death, but in addition, serum tumor necrosis factor (TNF) level was determined. RESULTS: The mortality rate of 60% in antibiotic treated animals was considerably reduced by G-CSF to 20%. All animals of the control group died during the observation period of 120 hours. A correlation between TNF levels and mortality rate was observed. In G-CSF treated animals total suppression of TNF serum levels was accessible in contrast to the others. CONCLUSIONS: In a clinically relevant animal model G-CSF was effective as an additional concept of prophylaxis. These data are promising toward clinical trials.

Animals↗
PubMed1993

Perioperative nonspecific histamine release: a new classification by aetiological mechanisms and evaluation of their clinical relevance.

As a consequence of the performance of a randomized controlled clinical trial on perioperative histamine release and cardiovascular and respiratory disturbances, several types of increases in plasma histamine had to be distinguished instead of only two which existed at the beginning of the study: drug-induced allergic and pseudoallergic reactions. First of all, the new classification by aetiology (clinical epidemiology) was derived from a meta-analysis (secondary analysis) of the most recent literature. According to that histamine release in the perioperative period has several, different causes and is involved in several, different disease manifestations. A clear distinction (classification), however, is necessary if histamine release as an unwanted (adverse) effect has to be recognized, value judged according to its clinical relevance and therefore also prevented by histamine antagonists. Histamine release by neuro-endocrine and neuro-inflammatory mechanisms, cytotoxic histamine release and local, cytokine induced histamine release have been distinguished from pseudoallergic histamine release, but its functions are not yet clear. It has been analysed in prospective trials which used special clinical situations as models: patients on a normal ward or before and during upper GI endoscopy without premedication, but also in specific phases of laparoscopic cholecystectomy (trocar phase and dissection phase). Their existence in the clinical reality is now very likely, but new trials must investigate the pathophysiological effects such as in metabolism, coagulation, pulmonary haemodynamics (shunt volume) and gastric acid secretion. Histamine release by pseudoallergic mechanisms, however, was identified in the very vulnerable post-induction phase of anaesthesia up to skin incision. Its incidence was much higher than ever expected and its clinical relevance was demonstrated by the severity of reactions and the intervention strategies of the anaesthetists who were blinded concerning the type of the plasma substitute given and the prophylaxis with antihistamines. Pseudoallergic histamine release was clearly unwanted (adverse). Its occurrence in the other phases of anaesthesia has to be further evaluated in the tedious procedure of data analysis of the Mainz-Marburg-trial. The overall incidence of histamine release in the trial was so incredible high (72% of all patients, some of them with up to 4 episodes of histamine release) that a distinction between pseudoallergic (unwanted) and other types of histamine release (possibly less unwanted or even beneficial) is urgently needed. In the phase of steady state (maintenance) of anaesthesia the H1-(+)H2-prophylaxis was highly effective. Further analysis must show whether this is also the case during the phases of induction of anesthesia.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1992

Intraoperative ultrasonography in surgery for chronic pancreatitis.

We report our experience with intraoperative ultrasonography in 49 patients undergoing surgery for chronic pancreatitis. Among drainage procedures, there were 14 laterolateral pancreaticojejunostomies, 15 pseudocystojejunostomies, and 2 pseudocystoduodenostomies. Under the guidance of intraoperative ultrasonography, left sided partial resection of the pancreas was performed in 7 patients, whereas a Whipple-type procedure was necessary in 6 cases. All preoperatively diagnosed pseudocysts, abscess formations, and dilated pancreatic ductal systems could be easily localized with the assistance of intraoperative ultrasound. Additionally to diagnoses already made preoperatively, intraoperative ultrasonography revealed a second, smaller pseudocyst in one patient and pancreaticolithiasis in another case. However, significant assistance and comfort to the operating surgeon was provided in all cases by intraoperative ultrasound imaging. This technique, which is cost effective and minimally invasive, proved to be extremely helpful in localizing pancreatic fluid collections and the course of the pancreatic duct. It facilitates the operation by reducing tissue traumatization and operative time. In experienced hands, intraoperative ultrasonography is a reliable method and a useful adjunct to the surgeon.

Adult↗
PubMed1992

[Histamine release during induction of combination anesthesia using nalbuphine or fentanyl. Modulation of the reaction by premedication with promethazine/pethidine].

In a controlled clinical trial in patients admitted for general surgery (mainly abdominal and thyroid), histamine release following nalbuphine 1 mg/kg i.v. versus fentanyl 5 micrograms/kg i.v. was studied in the course of an otherwise routine induction with promethazine/pethidine as premedication 30 min before the opioids and alcuronium-flunitrazepam-thiopental 5 min later. Succinylcholine was given before intubation and further analgesia was obtained by repeated administration of either nalbuphine or fentanyl. Plasma histamine levels were measured by a specific fluorometric assay, heart rate and blood pressure were measured for assessing hemodynamics, and clinical signs of anaphylactoid reactions such as skin eruptions and arrhythmias were registered. RESULTS. Nalbuphine and fentanyl both released histamine with an incidence of more than 40%. In addition, nalbuphine potentiated the histamine release evoked by the sequential administration of alcuronium-flunitrazepam-thiopental in one complex of application. The incidence of histamine release in the nalbuphine group was 6/13 = 46%, in the fentanyl group only 1/11 = 9% (chi2 test, P less than 0.05). Furthermore, this study showed high histamine levels after succinylcholine and intubation in a relation to time of administration that suggested histamine release as a stress response to intubation. Finally, the incidence of histamine release after a second injection of the opioids was still 30%. A direct correlation between plasma histamine levels, hemodynamic changes, and skin reactions could not be shown. A detailed causality analysis with histamine release as a contributory determinant showed histamine release less detrimental to hemodynamic stability than the opposite, which had been expected. However, the promethazine administered 30 min before induction of anaesthesia had strong H1- and H2-receptor antagonistic activity and was given with optimum timing for H1- and H2-prophylaxis. CONCLUSION. The study demonstrated that histamine release during anaesthesia and surgery depends strongly on the time sequence of drugs and measures used. Histamine release is not predictable from studies in human volunteers alone; studies in patients have to be added. Histamine release is not always detrimental. H3-receptor-mediated effects after H1- and H2-prophylaxis may help patients to counteract the effects of a series of vasoactive drugs given during induction of anaesthesia.

Adult↗
PubMed1992

[What is the cost of laparoscopic cholecystectomy?].

After laparoscopic cholecystectomy (LC) has replaced open cholecystectomy (OC) to a large extent as standard method in the operative treatment of cholecystolithiasis the question of costs and economics raises. To evaluate this question the data of 50 patients who underwent elective LC were analysed in a retrospective study and compared with the data of 50 patients who were cholecystectomized using the open technique. The median of in-hospital stay was 6 (3-15) days for LC and 10 (3-33) days for OC. The median of time of working-disability was 14 (2-35) days for LC and 21 (2-56) days for OC. Total cost (median) of 3788 (2637-8101) DM for LC compared to 4509 (2041-15218) DM for OC. The median of hospital income was 2790 (1395-6975) DM for the LC-group and 4650 (1395-15346) DM for the OC-group. Due to the shorter in-hospital stay of LC-patients this method causes a microeconomical loss for the hospital compared to OC. Macroeconomically LC represents a benefit because of shorter working-disability.

Adult↗
PubMed1992

[Acute abdominal pain--standardized findings as diagnostic support. Results of a prospective multicenter intervention study and testing of a computer-assisted diagnosis system].

Despite powerful diagnostic tools (e.g. ultrasound, special laboratory investigations), the diagnosis of acute abdominal pain is still a considerable problem. Several studies in the UK have shown that the diagnostic accuracy can be improved by structured and standardized history taking and clinical examination and by computer-aided diagnosis. In the framework of a concerted action of the European Community we have conducted a prospective multicenter interventional trial comparing two consecutive phases: a) a baseline phase in clinical routine without additional intervention, b) a test phase with structured and standardized history and clinical examination (questionnaire, documentation programme). In addition, a computer-aided diagnostic system developed in the UK was applied to the cases in the test phase. Outcome criteria were the diagnostic accuracy of the initial and the final examiner, the perforated appendix rate, the negative appendectomy rate, the negative laparotomy rate and the rates of diagnostic errors with missing indication to operation and of delayed urgent operations. No differences could be found between the phases with respect to the outcome criteria. In the baseline phase (test phase) diagnostic accuracy was 59% (59%), diagnostic accuracy after investigation (senior examiner) was 77% (78%), perforated appendix rate was 11% (16%), negative appendectomy rate was 13% (15%), negative laparotomy rate was 7% (8%), the rate of missed urgent indications to operation was 1.1% (1.9%) and the rate of delayed urgent operations was 3.4% (2.4%). Major differences between the centers were recorded. Computer-aided diagnosis resulted in a diagnostic accuracy of 51%. The introduction of structured and standardized history taking and clinical examination has not brought any improvement of the good results in clinical routine. It is doubtful, whether existing systems of computer-aided diagnosis are able to significantly decrease the still remaining error rate of 20%.

Abdomen, Acute↗
PubMed1991

Controlled clinical trials and cross-sectional studies with plasma histamine measurements and histamine receptor antagonists: solving the problem of preoperative H1- + H2-prophylaxis by asking new questions?

The problem of a preoperative histamine H1- + H2 - prophylaxis was tackled by a group of new studies including randomized controlled clinical trials and cross-sectional studies with plasma histamine measurements and administration of H1- + H2 - antagonists to a control group. The first study demonstrated serial histamine release in the induction of anaesthesia up to 4 times in a single patient. Basal plasma histamine levels in resting subjects fell below 100 pg/ml during the time necessary for preparation of the surgical patient. Hence, spikes of elevated plasma histamine concentrations corresponded to histamine release. Although this histamine release very often was less than 1 ng/ml plasma histamine, it created systemic reactions after atracurium. The cut-off point of 1 ng/ml for such anaphylactoid reactions does no longer exist, also lower plasma levels are of patho-physiological significance. The clinical signs of histamine release in the induction of anaesthesia vary from drug to drug. Sometimes tachycardia and hypertension produce the highest likelihood ratio, sometimes tachy- and bradycardia, but no changes in blood pressure as in the case of atracurium. It is concluded that the reasons why histamine release in anaesthesia and surgery is so much underreported and under-estimated include the present paradigms about plasma histamine levels and the "classical picture" of histamine release. Both are no longer valid and need a re-assessment.

Adolescent↗
PubMed1991

Elevated plasma histamine concentration as a sensitive real-time parameter for distinct phases of surgical trauma: a tool for technology assessment.

High technology plays an important role in surgery, either to expand surgical procedures or to reduce tissue trauma, which is a main goal of minimum invasive surgery. Due to the tremendous increase of costs the problem of technology assessment will not only be solved by statistical methods, but also by biomedical considerations and laboratory tests. Histamine release could be an indication for tissue trauma, which is caused directly by tissue damage or indirectly by infection or hypoxia. Therefore histamine release was investigated during different phases of operation in two clinically very important and complex situations: resection of liver metastases of colorectal carcinoma and resection of the oesophagus because of an oesophageal carcinoma. To model this situation in animal experiments, two randomized controlled studies were conducted in sheep. Traditional techniques were compared with techniques of minimum invasive surgery. Plasma histamine levels were determined at well-defined phases of the operation. Histamine release was demonstrated at distinct phases of operation indicating considerable specificity of this parameter, if sensitivity is guaranteed by advanced tests. Incision of the liver capsule by thermocauterization, liver ischaemia, tissue trauma in more extended disruption of perioesophageal tissue were causes of more extended histamine release. It is concluded that measurement of plasma histamine is a suitable indicator for discriminating between extended and minimum invasive surgery. The consequence of considering this parameter may be less complications in the post-operative period and a short hospital stay with better quality of life.

Animals↗
PubMed1991

[Ultrasonic diagnosis in suspected acute appendicitis: probable or certain indications for surgery?].

The diagnostic accuracy and the clinical impact of routine ultrasonography performed by 4 surgeons, were prospectively studied in 366 unselected patients admitted for suspected acute appendicitis. Clinical and sonographic findings on admission were correlated with laparotomy findings, pathological outcome and clinical as well as follow-up data. The overall sensitivity, specificity and accuracy of the clinical diagnosis of acute appendicitis were 55.3%, 94.6% and 84.2% respectively (positive predictive value (PPV) 75.8%, negative predictive value (NPV) 87.3%). Ultrasound enabled visualization of the disease in 67 of 85 (prevalence 23.3%) patients with a histologically confirmed acute appendicitis; false positive results were recorded in 7 cases (sensitivity 78.8%, specificity 97.5%, accuracy 93.1%, PPV 90.5%, NPV 93.8%). Ultrasound was particularly useful in patients presenting with equivocal or highly unsuspective signs of acute appendicitis: of 38 patients with an acute appendicitis in this group ultrasonography enabled to make the diagnosis in 26. The combined approach of clinical evaluation and routine ultrasonography markedly improved the diagnostic accuracy (sensitivity 85.9%, specificity 96.4%, accuracy 94%) and substantially reduced the negative laparotomy rate (7.9%) in patients with suspected acute appendicitis. It is concluded, that ultrasonographic evaluation of the patient with suspected acute appendicitis performed by surgeons is of great assistance in surgical practice.

Abdomen, Acute↗