Separate revascularization of the visceral arteries in thoracoabdominal aneurysm repair.

We successfully repaired a ruptured aortic patch containing the visceral arteries after thoracoabdominal aneurysm repair in a young patient with Marfan syndrome. This unexpected and tricky situation was treated by separate revascularization of each visceral artery using small-caliber prosthetic grafts as interposition between the aortic prosthesis and the ostia of the visceral arteries.

Microcirculation in chronic alcoholic pancreatitis: a laser Doppler flow study.

Experimental chronic pancreatitis is associated with microcirculatory disturbances but can also be induced or aggravated by perfusion changes. Microcirculatory alterations in human chronic pancreatitis are poorly defined. In this clinical study we investigated pancreatic microcirculation in the normal human pancreas and in chronic pancreatitis by laser Doppler flowmetry. Laparotomy was performed on 13 patients with nonpancreatic disease and on nine patients with chronic alcoholic pancreatitis for pancreatic head resection. Blood flow was measured over the pancreatic head, the uncinate process, over the mesenteric vein, the pancreatic corpus, and over the pancreatic tail by laser Doppler flowmetry. Blood flow was highest in the head of a normal pancreas with a mean of 436 +/- 34 perfusion units (PU), 399 +/- 43 PU in the uncinate process, 286 +/- 30 PU in the pancreatic corpus, and 351 +/- 46 PU in the tail of the pancreas. In the normal pancreas, lowest blood flow was measured over the mesenteric vein (228 +/- 23 PU). In chronic pancreatitis, blood flow in the pancreas was significantly decreased across the whole pancreas (p < 0.01). Furthermore flow-wave pattern was altered in chronic pancreatitis as compared with the normal pancreas. The normal human pancreas has a spatial variation in blood flow, correlating with the pancreatic arterial blood supply. In the chronically inflamed human pancreas, blood flow is significantly diminished, with a lower flow toward the pancreatic head.

Splanchnic microcirculatory changes during CO2 laparoscopy.

BACKGROUND: Splanchnic macrocirculatory changes during high-pressure CO2 pneumoperitoneum include a decrease in mesenteric arterial blood flow, and decreased gastric perfusion with a drop in gastric pH in experimental studies. Microcirculatory changes in abdominal organs under clinical conditions with a low pressure CO2 pneumoperitoneum are unknown. STUDY DESIGN: In 18 patients undergoing routine laparoscopy with a CO2 pneumoperitoneum (7 symptomatic cholecystolithiasis, 3 acute cholecystitis, and 8 acute appendicitis) gastric, duodenal, jejunal, colonic, hepatic, and peritoneal blood flow was measured with a custom-made laser Doppler flow probe at an intra-abdominal pressure of 0, 10, and 15 mm Hg. RESULTS: Intra-abdominal pressure elevation from 10 mm Hg to 15 mm Hg significantly decreased the blood flow in the stomach by 40 percent to 54 percent, the jejunum by 32 percent, the colon by 44 percent, the liver by 39 percent, the parietal peritoneum by 60 percent, and the duodenum by 11 percent. Splanchnic blood flow decreased with operative time at a constant intra-arterial pressure (r = 0.88, p < 0.0001). CONCLUSIONS: From our study, we concluded that laparoscopic procedures with a CO2 pneumoperitoneum should be performed at a pressure of 10 mm Hg or lower to avoid splanchnic microcirculatory disturbances.

Thoracotomy and thoracoscopy: postoperative pulmonary function, pain and chest wall complaints.

OBJECTIVE: Two different surgical accesses combined with standard pain management procedures are compared regarding early and intermediate pulmonary function and pain relief. METHODS: In a prospective study, 15 consecutive patients undergoing video-thoracoscopy for pulmonary wedge resection (group 1) were matched to 15 patients undergoing standard postero-lateral thoracotomy for lobectomy (group 2) according to age, gender and preoperative pulmonary function. Postoperative pain control consisted of patient controlled analgesia in group 1 and epidural analgesia in group 2. Pain intensity was scored from 0-4. The predicted postoperative pulmonary function (FVC and FEV 1) after lobectomies was calculated from the preoperative value according to the extent of resection. A clinical measurement was obtained after a mean follow-up time of 4.2 months. RESULTS: The ratios of postoperative measured to predicted values of FVC and FEV1 for group 1 compared with group 2 were 0.64 +/- 0.15 and 0.65 +/- 0.14 compared with 0.60 +/- 0.19 and 0.59 +/- 0.13, resp. (both n.s.) at the first day postoperative; 0.92 +/- 0.18 and 0.95 /- 0.17 compared with 0.76 +/- 0.20 (P < 0.05) and 0.83 +/- 0.23 (n.s.), resp. at hospital discharge; 0.98 +/- 0.10 and 0.94 +/- 0.14 compared with 1.01 +/- 0.17 (n.s.) and 1.10 +/- 0.17 (P < 0.05), resp. at follow-up. Pain intensity score one day after surgery ranged from 0.4 (resting position) to 1.6 (coughing) for group 1, and from 0.3 to 1.2 for group 2. Thirty-six percent of the thoracoscopy patients and 33% of the thoracotomy group complained of persistent pain or discomfort on the site of the operation after 3-18 months. CONCLUSION: Post-thoracotomy pain can be effectively controlled with epidural analgesia and pain intensity is no higher than in patients after thoracoscopy who are managed with patient controlled analgesia. FVC is slightly more decreased after thoracotomy during the early postoperative period. FVC and FEV 1 approach the predicted values after four months in both groups. The rate of persistent pain is similar after thoracoscopy and thoracotomy.

[Progress in surgical therapy of bronchus carcinoma]. / Fortschritte in der chirurgischen Therapie des Bronchuskarzinoms.

Surgical progresses in the treatment of lung cancer are not only related to technical details of surgery itself, but rely much upon an interdisciplinary approach before and after the operation. This will improve patient selection, multimodality treatment concepts and morbidity and mortality with overall improvement of quality of life in these patients.

Short-term influence of alcohol on spatial brightness contrast sensitivity.

The present crossover, controlled study demonstrates that alcohol at a blood concentration of approximately 0.08% reduces the contrast sensitivity (p less than 0.001). The mean contrast sensitivity was 15.03 dB in the control measurements and 14.39 dB in the measurements with alcohol. Brightness contrast sensitivity was measured with white, green, red and blue light, in this sequence. Therefore, the test design may present time effects as well as 'color effects'. The mean decrease in contrast sensitivity was with white light -1.26 dB, with green light -0.88 dB and with red light -0.57 dB. Contrast sensitivity tested with blue light showed even a slight increase with alcohol (+0.12 dB). The time interval between alcohol consumption and the test was important (p less than 0.001). The mean decrease in contrast sensitivity with alcohol in subjects with a short interval of 40 min was less reduced (-0.3 dB) than in subjects with a long interval of 60 min (-0.98 dB). In summary, at moderate doses of alcohol, contrast sensitivity is only moderately decreased and this decrease depends on the time between alcohol consumption and the test.

Spatial brightness contrast sensitivity measured with white, green, red and blue light.

Grating contrast sensitivity was measured using different colors and different grating orientations. The contrast sensitivity was highest when measured with green light, a little less when measured with red light, and lowest with blue light. The contrast sensitivity with blue light was relatively low compared with green and red light for high spatial frequencies, and relatively high for low spatial sensitivities. The so-called 'oblique effect' was confirmed in this study, but a difference between horizontal and oblique gratings was only found in spatial frequencies higher than 18 cycles/degree. The present study, carried out on 20 persons, suggests that the inter- and intraindividual components of variance are smallest when measured with green light and vertically oriented gratings.

The influence of alcohol on the outcome of automated static perimetry.

It is well known that perimetric findings fluctuate within a single examination. There is additional fluctuation between perimetric examinations. The cause of this fluctuation is not yet fully understood, but such things as changes in attention, patient cooperation, or drugs have been discussed. To study such possible factors, we carried out perimetry on subjects who had consumed alcohol and who had not. The results indicate that alcohol, at a blood concentration of approximately 0.08%, barely influences the results of static automated perimetry. Differential light sensitivity remained unchanged by alcohol at all eccentricities tested. A decrease in the ability to cooperate was manifested by a significant higher score of false-positives in catch trials. There was also a tendency toward an increase in false-negative responses in catch trials, an increase in the number of stimuli presentations required, and higher short-term fluctuation. Lack of the influence of alcohol on the differential light threshold does not necessarily mean that alcohol has no influence on visual function. It indicates, however, that differential light sensitivity, as measured with the automated perimeter Octopus, is not influenced by moderate alcohol ingestion.

Effects of epidural anaesthesia on microcirculatory blood flow in free flaps in patients under general anaesthesia.

It has been suggested that epidural anaesthesia may increase blood flow in free flaps on the lower extremity. The objective of the present study was to test this hypothesis in 21 patients undergoing reconstructive surgery of the lower extremity with free muscle (n = 8), fasciocutaneous (n = 6) or musculocutaneous (n = 7) flaps. Microcirculatory blood flow was measured continuously with a multichannel laser Doppler flowmetry, both in muscle and skin of the free flap as well as in the intact skin and muscle on the same extremity. After completion of surgery, general anaesthesia was continued and the epidural block was induced by an injection of 2% lignocaine-hydrochloride into a pre-operatively inserted and tested epidural catheter. The epidural block caused no change in microcirculatory flow in the intact skin and muscle, however, it resulted in a marked decrease in microcirculatory blood flow in all the free flaps studied (20-30%; P < 0.05). The epidural block also caused a significant decrease in mean arterial blood pressure, from 85 (+/- 2.8) mmHg to 68 (+/- 2.8) mmHg (P < 0.01). It was concluded that epidural anaesthesia may decrease microcirculatory blood flow in free flaps on the lower extremity by diverting flow away from the flap to normal intact tissues (a steal phenomenon).

[Effect of grid orientation of interference patterns on contrast sensitivity in white and colored light]. / Der Einfluss der Streifenrichtung von Interferenzmustern auf die Kontrastempfindlichkeit bei weissem und farbigem Licht.

The contrast sensitivity of 34 healthy eyes and 32 suspected of having glaucoma was measured at 3, 6, 12, 18, and 24 cycles/degree with vertical, oblique and horizontal interference fringes. These were produced by the Haag-Streit Visometer as modified by Lotmar with an additional device for contrast variation. At all frequencies, maximum contrast sensitivities were found for vertical gratings. However, there was a tendency for oblique gratings to show relatively low contrast sensitivities at high spatial frequencies; the same applied for horizontal gratings at low frequencies. The effect of stimulus orientation was similar for white, red, green and blue light.

A direct search procedure to optimize combinations of epidural bupivacaine, fentanyl, and clonidine for postoperative analgesia.

BACKGROUND: The authors applied an optimization model (direct search) to find the optimal combination of bupivacaine dose, fentanyl dose, clonidine dose, and infusion rate for continuous postoperative epidural analgesia. METHODS: One hundred ninety patients undergoing 48-h thoracic epidural analgesia after major abdominal surgery were studied. Combinations of the variables of bupivacaine dose, fentanyl dose, clonidine dose, and infusion rate were investigated to optimize the analgesic effect (monitored by verbal descriptor pain score) under restrictions dictated by the incidence and severity of side effects. Six combinations were empirically chosen and investigated. Then a stepwise optimization model was applied to determine subsequent combinations until no decrease in the pain score after three consecutive steps was obtained. RESULTS: Twenty combinations were analyzed. The optimization procedure led to a reduction in the incidence of side effects and in the mean pain scores. The three best combinations of bupivacaine dose (mg/h), fentanyl dose (microg/h), clonidine dose (microg/h), and infusion rate (ml/h) were: 9-21-5-7, 8-30-0-9, and 13-25-0-9, respectively. CONCLUSIONS: Given the variables investigated, the aforementioned combinations may be the optimal ones to provide postoperative analgesia after major abdominal surgery. Using the direct search method, the enormous number of possible combinations of a therapeutic strategy can be reduced to a small number of potentially useful ones. This is accomplished using a scientific rather than an arbitrary procedure.

Evaluation of laser doppler flowmetry for the study of benign and malignant gastric blood flow in vivo.

BACKGROUND: Tumour vascularisation is a determinant of the development of metastases. AIMS: To measure blood flow in normal stomach and gastric adenocarcinomas by laser Doppler flowmetry and correlate blood flow with vascularisation after immunohistochemical staining of resected specimens for CD31 and von Willebrand factor. PATIENTS: Twenty two undergoing resection for gastric adenocarcinoma and 10 undergoing cholecystectomy. RESULTS: Mean (SD) gastric blood flow was 208 (35) perfusion units (PU) in patients undergoing cholecystectomy and 190 (75) PU in the undiseased part of the stomach in patients with gastric adenocarcinoma. Gastric blood flow was higher in the border of gastric adenocarcinomas (322 (120) PU, p<0.01 v normal stomach) but lower in the centre (74 (27) PU, p<0.01 v normal stomach and tumour border). Blood flow was higher in tumours staged T>/=3 than in those staged T<3. Blood vessel density in normal stomach was 41 (8) stained cells/field viewed and was 1. 9-3.4 times higher in gastric adenocarcinomas. CONCLUSION: Laser Doppler flowmetry is a valuable tool for studying the pathophysiological alterations of malignant blood flow in the human stomach in vivo.

Role of thromboxane and leukotriene B4 in patients with acute respiratory distress syndrome after oesophagectomy.

We have studied prospectively the clinical course and serum concentrations of thromboxane B2 (TxB2) and leukotriene B4 (LTB4) in patients developing adult respiratory distress syndrome (ARDS) after oesophagectomy. The clinical course was assessed according to a validated ARDS score, and intra- and postoperative measurements of TxB2 and LTB4 in pre- and post-pulmonary blood were performed in 18 patients undergoing oesophagectomy for oesophageal carcinoma and 11 control patients undergoing thoracotomy and pulmonary resection. Six of 18 patients undergoing oesophagectomy, but no control patient, developed ARDS. The ARDS score was highest on day 8 after operation. Only patients with ARDS had a significant postoperative increase in post-pulmonary, but not pre-pulmonary, TxB2 concentrations (P < 0.05 vs patients without ARDS). This study provides evidence that TxA2, originating from the lungs, was associated with the development of ARDS after oesophageal resection. In view of the high incidence of ARDS after oesophagectomy (10-30%), prophylactic treatment of patients undergoing oesophageal resection with clinically applicable thromboxane synthetase inhibitors may be warranted.