[Comparative study of pancreatic head resection in chronic pancreatitis]. / Pancreasfej-reszekciók összehasonlító vizsgálata chronicus pancreatitisben.

Between 1991 and 1998 the authors performed 21 pylorus-preserving pancreatoduodenectomies (PPPD), 32 Beger and 13 Frey procedures in chronic pancreatitis with inflammatory head enlargement. The pre- and intraoperative data, as well as the postoperative early and late results were also compared. The preoperative clinical features and the intraoperative morphology were similar in the three groups. Considering the operative and late mortality and the reoperation there was no statistical difference between the procedures. The postoperative hospitalization time was the shortest after the duodenum-preserving pancreatic head resections (Beger and Frey). While the rate of early complications was significantly higher after PPPD, there was no difference in the rate of late complications between the groups. Although each operation gave similarly good late results (freedom from pain, weight gain, exocrine function, quality of life), the condition of the patients was better and the development rate of diabetes was lower (1/27), after Beger procedure, that after PPPD (6/14). Consequently the duodenum-preserving pancreatic head resections seem to be more advantageous, than the PPPD. Nevertheless the latter procedure is the only possibility in some cases.

Late complications after pharyngogastrostomy.

A case of severe stricture and a case of tracheogastric fistula after laryngopharyngo-esophagectomy and pharyngogastrostomy for cervical esophageal cancer are described. Stricture is often seen but tracheogastric fistula is a rare complication, however, both are devastating conditions. According to the literature, the survival rate is poor in both cases. The surgical management demands several principles. Recurrent or metastatic cancer must be ruled out. The patients' general condition and nutritional status must be optimized. Pulmonary infection must be cleared. The surgical management of the stricture was a free jejunal transfer after failed attempts of several dilation procedures. The treatment of tracheogastric fistula was suturing the stomach and covering the trachea with a pedicled left sternocleidomastoideus flap. The survival of the patient treated with free jejunal interposition exceeds 24 month. Unfortunately, the patient with tracheogastric fistula, treated with interpositioned sternocleidomastoideus muscular flap, lived two weeks after this operation. The surgical managements described in this report may provide palliation or definitive treatment for these devastating complications.

Methylene blue restores vasodilation to bradykinin after inhibition of nitric oxide production in the isolated dog lung.

Methylene blue (MB) is a widely used putative inhibitor of nitric oxide (NO)-dependent responses, particularly in cell culture and vascular ring studies. MB is postulated to diminish vasodilation to NO either by preventing activation of guanylate cyclase by NO or by oxidizing NO formed by NO synthase. In the present study we examined whether MB inhibited vasodilation to bradykinin (BK) in the cyclooxygenase-inhibited, isolated canine lung lobe perfused with blood at constant flow. One group of lobes (n = 5) was challenged with BK at baseline vascular tone, after tone was doubled by infusion of serotonin (5-HT), and again after MB treatment. Bradykinin challenge failed to evoke a depressor response at baseline vascular tone but induced marked vasodilation after vascular tone was increased by 5-HT. Subsequent treatment with MB, however, failed to significantly diminish vasodilation to BK (p > 0.05). A second group of lobes (n = 4) was challenged with BK after cyclooxygenase inhibition and the doubling of vascular tone with serotonin infusion. The dose-dependent vasodilation to BK was diminished (p < 0.01) after treatment with 1.8 mM N omega-nitro-L-arginine (L-NA), a potent inhibitor of nitric oxide synthase. However, subsequent treatment with MB restored the vasodilator response to bradykinin to pre-L-NA values (p < 0.01). While our results suggest that vasodilation to bradykinin is mediated in part by NO formation, MB treatment does not appear to alter BK-induced vasodilation, and even enhanced vasodilation to bradykinin after L-NA. MB appears to have some nonspecific effects on vascular tone and reactivity that are unrelated to NO formation.

Effect of methylene blue on vasoreactivity in dog lung.

We examined the effect of methylene blue (MB), a putative inhibitor of guanylate cyclase (GC) activation by endothelium-derived relaxing factor (EDRF) and nitrovasodilator compounds, on vascular tone and reactivity to vasoactive substances in the isolated, blood-perfused canine lower left lung lobe. Lobar vascular resistance was partitioned into arterial and venous segments by venous outflow occlusion. Because MB did not alter vasoconstriction to either serotonin or acetylcholine (P greater than 0.05) except after cyclooxygenase inhibition (COI), we determined the effectiveness of MB as an inhibitor of GC activation by nitrovasodilators. Lobes were given graded bolus doses of nitroglycerin (GTN), sodium nitroprusside (SNP), and bradykinin (BK) at baseline vascular tone, after COI, and after vascular tone was raised by either U-46619, a thromboxane analogue, or MB infusion. GTN and BK but not SNP induced dose-dependent vasodilation when vascular tone was raised by U-46619. However, when vascular tone was increased to a similar level by 30 mg MB and 0.5 mg/min infusion, vasodilation to GTN, SNP, and BK was enhanced from U-46619 infusion. In contrast to MB, NG-nitro-L-arginine, a putative inhibitor of EDRF synthesis, diminished vasodilation to BK in cyclooxygenase-inhibited lobes with elevated vascular tone. Because MB potentiated vasodilation to GTN, SNP, and BK, it is questionable whether MB is an effective inhibitor of vasodilation to nitrovasodilators or BK in the isolated, blood-perfused canine lung.

Effects of different cyclooxygenase inhibitors on the segmental distribution of pulmonary vascular resistance in the dog.

An increase in pulmonary vascular resistance (PVR) after cyclooxygenase inhibition (COI) is well documented in the dog, but the site of vasoconstriction to chemically distinct cyclooxygenase inhibitors is largely unknown. The purpose of the present study was to examine and compare equimolar concentrations of three chemically unrelated cyclooxygenase inhibitors, indomethacin (INDO; n = 6), meclofenamate (MECLO; n = 6) and ibuprofen (IBU; n = 5), upon the longitudinal distribution of PVR in the isolated canine lower left lung lobe perfused at constant flow with autologous blood. At successive increases in the blood concentration of each cyclooxygenase inhibitor, PVR was partitioned into upstream (arterial, Ra), middle (Rm) and downstream (venous, Rv) resistance by arterial and venous flow occlusion with capillary pressure estimated by a double flow occlusion technique. All three cyclooxygenase inhibitors produced significant pulmonary vasoconstriction with the largest increase in PVR after INDO (104 +/- 21%) and the smallest after IBU (69 +/- 10%). The PVR increase in the INDO and MECLO group was related to an elevation in both Ra (p less than 0.01) and Rv (p less than 0.01), whereas only Rv was increased by IBU (p less than 0.01). While none of the cyclooxygenase inhibitors increased Rm (p greater than 0.05), capillary pressure was increased from pretreatment levels by each cyclooxygenase inhibitor. Although each of the three chemically distinct cyclooxygenase inhibitors raised PVR, the segmental distribution of PVR and the magnitude of the capillary pressure increase varied at equimolar blood concentration.

Density analysis of scintigram with flow dynamics at bolus radionuclide venography: count correction with velocity.

The authors analyse the difference in the density of dynamic scintigrams produced in radionuclide venography. The difference in density is always connected with the velocity of the radionuclide flow. The lost activity is found after multiplying the count difference calculated from the time activity curve by velocity. The importance of the investigation is that the capacity of different venous channels can be determined in radionuclide venography by this method of calculation.

Testing minimal transit time in the venous system of the lower limbs using dynamic radionuclide venography.

The Authors used a test of venous occlusion applied during plethysmography in performing radionuclide venography. The minimal transit time of maximal venous outflow was tested in the subinguinal region using 99mTc-DTPA. Significant differences could be observed in compensated and non-compensated cases of occlusion of the iliac vein and chronic venous insufficiency caused by primary varicosity if compared to the controls. The functional change of suprapubic venous bypass was examined after Palma operation. Such a dynamic bolus radionuclide venography is considered to be suitable for extending the preoperative selective methods of reconstruction operations and monitoring patients postoperatively.