[Infrarenal aortic aneurysm: results of surgical treatment]

Between 1976 and 1987 93 patients with an infrarenal aortic aneurysm underwent surgical correction. In 62 patients the procedure was performed electively, whilst 13 displayed an unstable aneurysm and in 18 cases a ruptured aneurysm was present at operation. During the past 5 years the mortality was lowered to 2% in elective cases, whereas in cases of ongoing rupture only moderate improvement took place. The most frequent cause of a lethal outcome was pump failure of the heart (6 times), followed by renal insufficiency and haemorrhagic shock and bleeding complications. Among the non-lethal complications, relaparotomy on the basis of postoperative bleeding ranks first, followed by pulmonary insufficiency, peripheral emboli and partial ischemia of the spine. Resection of infrarenal aneurysms should be performed in the stable state of disease, since insufficiency of multiple vital organ systems increases the mortality by up to 20 fold.

The results of operative treatment of osteochondritis dissecans of the patella

The course of osteochondritis dissecans (OCD) of the patella and the results of operative treatment are analyzed retrospectively in a review of 31 operatively treated cases in 25 patients. Followup was obtained for 21 cases, with an average of 73 months (range, 15 months to 20 years). These 25 patients were predominantly males, and averaged 18 years of age at the time of surgery. A history of trauma was associated with the lesion in 38% of the cases, and the lesion was bilateral in one out of four patients. The most common presenting complaints were subpatellar pain and swelling. The most common initial physical findings were patellofemoral crepitus and joint effusion. Forty-four operations were performed on 31 knees. The most commonly performed procedures were curettage of the patella and removal of loose bodies, in combination or as part of another procedure. A new patellofemoral rating scale was used to evaluate results. Thirty-eight percent of the knees had a good or excellent result, while 62% had a fair or poor result. Persistent pain with restricted function and residual patellofemoral crepitus were common findings. In general, the patients who come to surgery for OCD of the patella have a guarded prognosis for full recovery of knee function.

Surgical therapy of radiation-induced lesions of the colon and rectum

Thirty-six operations for late sequelae of radiotherapy were carried out in 31 patients from 1971 to 1986. The most frequent indications for surgery were stricture (58 percent) and fistula (29 percent). In the first 8 year period from 1971 through 1978, 13 of 14 operations were diversions (colostomy or by-pass). From 1979 through 1986, a more aggressive approach prevailed. Only 32 percent of the operations were diversions. This more aggressive strategy was accompanied by a decrease of the postoperative mortality rate from 21 percent through 1978 to 0 in the later period. The overall complication rate was 23 percent. Complications were relatively more frequent after two-layer sutured or stapled anastomoses and after resection or fistula closure without temporary colostomy. We conclude that in radiation-induced colonic and rectal lesions, diversion should be performed in patients with unproved cure of disease or tumor persistence. Resection and fistula closure can be carried out safely, and a temporary colostomy is strongly recommended.

[Prognostic factors in cardia cancer]

Among 164 patients operated upon for adenocarcinoma of the cardia 102 (61%) were resected, 87 of them with curative intent. The mortality within 30 days was 20%, and the 5-year survival 15%. A total gastrectomy was performed in 36 patients, whereas a proximal partial gastrectomy was carried out in 66 cases. The median survival was 19 months after total gastrectomy, and 11 months after proximal resection (Breslow: 0.22). Only in stages N0 and N1 total gastrectomy resulted in a significantly longer (32 months) median survival than proximal resection (11 months; p = 0.03). The impact of total gastrectomy was more pronounced in the diffuse type according to Lauren, whereas lymphadenectomy was more effective in stages N0 and N1 and in Lauren's intestinal type. It is concluded that total gastrectomy should be carried out in all cases of carcinoma of the cardia.

[Diagnosis of peritoneovenous shunt occlusion]

Reaccumulation of ascitic fluid after peritoneovenous shunt implantation demands accurate diagnostic procedure. Between 1973 and 1985 81 peritoneovenous shunts have been implanted at the IInd Surgical Department of the University of Vienna. In the same time 34 reoperations in 17 patients have been performed for reasons of shunt-dysfunction. Besides thorax x-ray, diagnosis was established in 11 cases by means of Doppler ultrasound investigation, in 26 cases by technetium scan and in 15 cases by shunt angiography. Shuntography proved to be the method of choice, with no false results. Doppler ultrasound results were unclear in a high percentage, thus this method is not used any more.

Event-related cross-correlations between spike trains illustrated on interactions between motor units and muscle spindle afferents

A method is presented for computing correlation coefficients of two (or more) output spike trains in temporal relation to one (or more) input even trains. These event-related correlation functions are computed by convolving the output spike trains, represented as point processes, with rectangular pulses of selectable width, and by then calculating linear correlation coefficients for the pairs of amplitude values obtained from the two convolved processes in temporal relation to the input events. The merits of this technique are illustrated on stimulus trains delivered to motor units (MUs) and output spike trains recorded from muscle spindle afferents of the same cat hindlimb muscle. The correlation functions obtained show the temporal course of the correlated firings of the two afferents (mostly Ia afferents from primary muscle spindle endings) as a function of time from MU activation; they are compared with the conventional cross-correlation histograms (CCHs) between afferents and with peri-stimulus time histograms (PSTHs) between stimulus and afferent firing patterns. Stimulus-related cross-correlation functions as displayed here can be calculated for any three spike trains. Possible extensions of the method to larger numbers of input and output channels are also discussed.

Effect of the prokinetic drug cisapride on gastrointestinal hormone release

The influence of the prokinetic drug cisapride on the release of gastrointestinal hormones was studied in volunteers. First, acute effects of single doses of cisapride compared with saline were investigated. Cisapride at doses of 8 mg and 20 mg intravenously significantly increased plasma concentrations of pancreatic polypeptide (hPP) by 145% and 146%, respectively. Cholecystokinin (CCK) levels were increased by 176% at 8 mg cisapride, whereas gastrin and insulin levels remained unchanged. Enhancement of PP and CCK secretion was almost completely abolished by pretreatment with 1 mg atropine. Carbachol (250 micrograms subcutaneously) increased PP release by 62% but did not affect the other hormones. Second, the influence of a 1-week treatment (10 mg three times daily, given orally) on plasma hormone levels was studied. After 1 week the postprandial CCK release was diminished by 58%. Basal levels and postprandial responses of gastrin, PP, and insulin were not altered by prolonged cisapride administration. It is concluded that acute application of cisapride stimulates secretion of PP and CCK via atropine-sensitive mechanisms and that chronic treatment with cisapride diminishes CCK release by an unknown mechanism.

Role of endogenous prostaglandins in somatostatin-induced inhibition of gastrointestinal hormone secretion

Endogenous prostaglandins have been reported to be essential for the inhibitory effect of somatostatin on acid secretion. From these results it could be suggested that the effect of somatostatin on the secretion of gastroentero-pancreatic hormones may also be medulated by prostaglandins. This hypothesis was investigated in man and in the rat. Somatostatin-induced inhibition of postprandial gastrin, cholecystokinin, pancreatic polypeptide, and insulin release was not influenced by indomethacin pretreatment in healthy subjects. Using the isolated perfused rat stomach preparation, inhibition of acetylcholine-stimulated gastrin secretion by somatostatin was found to be unchanged by indomethacin treatment. It is concluded that endogenous prostaglandins are unlikely to be indispensable for the inhibitory effect of somatostatin on gastroentero-pancreatic endocrine cells.

The dissociation of the extracellular hemoglobin of Tubifex tubifex at extremes of pH and its reassociation upon return to neutrality

The dissociation of the extracellular hemoglobin of Tubifex tubifex at alkaline and acid pH, and its reassociation upon return to neutral pH, was investigated using gel filtration, ultracentrifugation, and polyacrylamide gel electrophoresis in sodium dodecyl sulfate (SDS-PAGE). Tubifex hemoglobin dissociated at pH above 8 and below 6; both dissociations appeared to be equilibrium processes. The extent of dissociation increased as the pH moved away from neutrality; although dissociation was virtually complete at pH 11, its extent at acid pH did not exceed 50-60% at pH 4. Ca(II), Mg(II), and Sr(II) cations over the range 1-100 mM decreased the extent of the dissociation only at alkaline pH. The visible absorption spectrum of the oxyhemoglobin remained unaltered in the pH range 4-9. At more extreme pH, it changed with time, altering irreversibly to that of the aquo ferri form. Gel filtration of the hemoglobin at both extremes of pH showed that it dissociated into two heme-containing fragments; one consisting of subunit 1 (Mr approximately 17,000) and the other containing subunits 2, 3, and 4 of the hemoglobin (Mr approximately 60,000). Upon return to neutral pH, the dissociated fragment reassociated to the extent of 50 to 80% to whole hemoglobin molecules. The reassociation decreased with increase in alkaline pH, and with decrease in acid pH to which the hemoglobin had been exposed; it increased in the presence of Ca(II), Sr(II), and Mg(II) only subsequent to dissociation at alkaline pH. The SDS-PAGE patterns, gel-filtration elution volumes, and alpha-helical contents, determined from circular dichroism at 222 nm, of the reassociated whole molecules were identical to those of the native hemoglobin.

Growth hormone, cortisol, and glucagon concentrations during plasma free fatty acid depression: different effects of nicotinic acid and an adenosine derivative (BM 11.189)

Two chemically unrelated inhibitors of lipolysis were used in order to differentiate between the effect of FFA depression and a possible FFA-unrelated drug effect, respectively, on the plasma concentrations of GH, cortisol, and glucagon. Saline infusion served as a control experiment. In eight healthy male volunteers, a similar FFA depression by either iv infusion of nicotinic acid (3-pyridine-carboxylic acid, NA) or oral intake of an adenosine derivative, N(6)-allyl-N(6)-cyclohexyl-adenosine (AD-D), was followed by a significant GH increase (to 22.1 +/- 6.2 and 9.6 +/- 2.9 ng/ml at 240 and 270 min, respectively). Due to the large scatter of the GH concentrations during NA infusion, these responses were not significantly different. No GH increase occurred when the FFA depression was prevented by addition of a lipid infusion. In contrast, plasma cortisol and glucagon both increased significantly (by 107.4 micrograms/liter at 270 min and by 48.4 pg/ml at 60 min, respectively) during NA- but not during AD-D-induced FFA depression. Addition of the lipid infusion abolished the cortisol increase during NA infusion but had no influence on basal cortisol concentrations during AD-D intake. It lowered glucagon to values slightly below basal concentrations when added to the NA infusion and more markedly during AD-D administration. The results provide evidence that 1) depression of plasma FFA per se stimulates the secretion of GH, and 2) the increase of cortisol and glucagon during NA infusion is probably unrelated to the FFA depression. Hence, the stimulatory effect of FFA lack on glucagon secretion needs to be reconsidered.

[Treatment with 10% glycerin in acute ischemic cerebral infarct. Doubleblind study]

56 patients with acute ischemic cerebral infarction were randomly allocated to intravenous treatment for 6 days with either 500 ml of a 10% glycerol solution or 500 ml of a 5% dextrose solution (placebo). The neurological status of the patients was evaluated by a blinded investigator before the beginning of the treatment, after 2 weeks and again after 6 months. According to the initial degree of neurological deficit, patients were stratified into a mild, intermediate and severe group (using a scoring system). After 2 weeks there was significantly less neurological deficit in the total glycerol-treated group than in the placebo group (2p less than 0.02). This favourable effect of glycerol was even greater in the patients with an initially intermediate degree of neurological deficity (2p less than 0.01). After 6 months there was no difference between the total glycerol-treated and the placebo group. A beneficial effect of glycerol treatment, however, was still demonstrable in the intermediate group (2p less than 0.05). Mortality was not influenced by glycerol treatment. No side effects of the glycerol treatment could be detected. Intravenous administration of 10% glycerol can thus be recommended in patients with acute cerebral infarction.

Logopaedic findings following advancement of the maxilla

From 1972 to 1974, the authors carried out logopaedic examinations of over 100 patients with retrodisplaced maxillae at the Clinic for Maxillo-Facial Surgery at the University of Zurich (Director: Prof. H. Obwegeser, M.D., D.M.D.). From this clinical material, 40 cases which were fully documented in respect of medical history, surgical treatment and speech behavior were selected, and the effect of the advancement of the maxilla on the individual ability to articulate was studied.