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993.
Effects of long-term propranolol and octreotide on postprandial hemodynamics in cirrhosis: a randomized, controlled trial 总被引:6,自引:0,他引:6
Vorobioff JD Gamen M Kravetz D Picabea E Villavicencio R Bordato J Ruf A Bessone F Romero G Palazzi J Nicora A Passamonti M Tanno H 《Gastroenterology》2002,122(4):916-922
BACKGROUND & AIMS: Postprandial increases in portal pressure may influence esophageal variceal rupture. The effects of chronic propranolol and octreotide (100 and 200 microg subcutaneously in a single dose) on postprandial hemodynamics were evaluated. METHODS: FIRST STUDY: 36 cirrhotic patients were studied at baseline and 30 and 60 minutes after a standard meal and then treated with propranolol (139 +/- 9 mg/d during 39 +/- 2 days). SECOND STUDY: After baseline measurements, patients were randomized into 3 groups: (1) placebo, (2) octreotide (100 microg), or (3) octreotide (200 microg) (n = 12 for each group). Thirty minutes postinjection a new baseline was established and measurements were repeated 30 and 60 minutes after the meal. RESULTS: First study: Baseline portal pressure was 18.1 +/- 1.2 mm Hg, 30 and 60 minutes after the meal it was 21.5 +/- 0.8 mm Hg and 20.5 +/- 0.8 mm Hg, respectively (both P < 0.01 vs. baseline). Cardiac index (CI) was 4.5 +/- 0.2, 4.8 +/- 0.2, and 4.9 +/- 0.2 L x min(-1) x m(-2), respectively (both P < 0.05 vs. baseline). Peripheral vascular resistance was 1012 +/- 56, 902 +/- 51 (P = NS), and 884 +/- 49 dynes x sec x cm(-5) (P< 0.05 vs. baseline), respectively. Second study: Propranolol and placebo did not blunt postprandial increase in portal pressure. Octreotide (100 microg) partially ameliorated postprandial increase in portal pressure. Octreotide (200 microg) significantly enhanced the portal hypotensive effect of propranolol and blunted the postprandial increase in portal pressure. CONCLUSIONS: Octreotide blunts postprandial increase in portal pressure not prevented by long-term propranolol administration. 相似文献
994.
Despite an increasing incidence of spinal cord injury (SCI) in the elderly and evidence that age appears to influence outcome after neurotrauma, surprisingly little is known regarding clinical outcomes and secondary complications in elderly with an acute SCI. This study was undertaken to evaluate the effect of age on clinical outcomes after acute traumatic SCI managed in an acute care unit by a multidisciplinary team. A retrospective chart review of all patients with acute SCI admitted to an acute care unit at a university hospital between 1998 and 2000 was performed. Data on clinical outcomes and secondary complications in younger individuals (group 1: age < 60 years) were compared to elderly subjects (group 2: age > or = 60 years). There were 28 elderly (age 60-89 years) and 30 younger (age 17-56 years) individuals. The severity and level of SCI were similar in both groups (p = 0.11; p = 0.93). Co-morbidities were more frequent in the elderly (p < 0.01). There was a trend, which did not achieve significance, for an increased incidence of secondary complications in the elderly (57.1% versus 33.3%; p = 0.11). The most common secondary complications in both groups were infections, psychiatric disorders, pressure sores, and cardiovascular complications. Mortality rates in elderly and younger individuals with acute SCI (p = 0.41) were not significantly different. Our data suggest that rigorous attention to principles of acute SCI care can minimize previously reported higher susceptibility for secondary complications in the elderly. A multidisciplinary team approach to the management of the elderly with acute SCI is essential to minimize or prevent secondary complications. 相似文献
995.
Autonomic dysreflexia in acute spinal cord injury: an under-recognized clinical entity 总被引:9,自引:0,他引:9
While autonomic dysreflexia (AD) is well recognized in the chronic stage of spinal cord injury (SCI) this potentially life-threatening complication has been only rarely documented in the acute phase (1 month) after SCI. Based on our clinical experience we hypothesized that AD is under-recognized in the acute phase of SCI. This study was undertaken to determine the incidence and clinical associations of early AD in our center. We reviewed the charts of patients with acute traumatic SCI admitted to the Toronto Western Hospital Spinal Program between 1998 and 2000. Among 58 patients with acute traumatic SCI (15F, 43M; ages 17-89 years, mean of 55.4), all three individuals who developed evidence of early AD had complete cervical tetraplegia (1F, 2M; ages 31-42 years, mean of 38.3). The incidence of early AD was 5.2% (3 of 58), whereas the adjusted incidence for the population at risk (SCI at T6 or above) was 5.7% (3 of 53). A significant number of patients in this series (87.9%, or 51 of 58) had a cervical SCI. While the mean resting systolic arterial blood pressure among these three individuals was 105.7+/-3 mm Hg, the mean systolic blood pressure at the time of early AD was 173.3+/-14.8 mm Hg (increase in systolic blood pressure over baseline ranged from 35.5% to 95%). The earliest episode of AD occurred on the 4(th) post-injury day. The trigger mechanisms for AD were somatic pain, fecal impaction, and abdominal distention. Although numerous reports emphasize AD as a potential complication of chronic SCI, our study demonstrates that AD occurs in 5.7% of patients with acute SCI above T6. Patients with severe cervical SCI are particularly susceptible to the early onset of AD. Clinicians need to be aware and highly vigilant of the potential development of AD in the acute phase of SCI. 相似文献
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998.
Uribe N García-Granero E Millan M Belda J Calvete J García-Granero M 《Digestive surgery》2003,20(1):24-31
OBJECTIVE: To evaluate the effects of positive end-expiratory pressure (PEEP) on residual vascularization in gastric tubes for oesophageal replacement. DESIGN: Experimental open study. MATERIALS: Eleven mongrel dogs. METHODS: Intestinal parietal blood flow was evaluated by photoplethysmography (PPG) and measurement of surface oxygen (PsO(2)) and carbon dioxide (PsCO(2)) tensions under basal conditions. After Akiyama's tubular gastroplasty, three levels of PEEP were administered. At each level, fluids were infused to counter the drop in cardiac output. PPG, surface gas tensions, arterial pressure, cardiac output and arterial blood gas tensions were monitored. Control sections of the bowel were also monitored by PPG. RESULTS: Cardiac output dropped for each level of PEEP and returned to basal levels on volume restabilization and on removal of PEEP. Central venous pressure and pulmonary arterial and capillary pressures increased for each level of PEEP and only returned to basal levels on removal of PEEP. PsO(2) values dropped for each level of PEEP and returned to basal levels on volume restabilization and on removal of PEEP. PsCO(2) levels rose, and PPG wave amplitude dropped, for each level of PEEP; these two variables only returned to basal levels on removal of PEEP. PPG values for the control sections reflected those of the anastomotic area. CONCLUSIONS: PEEP affects surface oxygen values at the level of the gastroplasty by means of its effect on cardiac output. PEEP also creates a venous return compromise and PPG wave amplitude and surface carbon dioxide values are related to this compromise. All three variables could be significant in anastomotic wound healing. 相似文献
999.
Urodynamic changes induced by the intravaginal electrode during pelvic floor electrical stimulation 总被引:1,自引:0,他引:1
AIMS: The goal of this study was to evaluate whether the intravaginal electrode used to perform vaginal electrical stimulation could induce acute changes on the cystometrograms and urethral pressure profiles (UPP) recordings. METHODS: Three consecutive urodynamic examinations were performed on 30 women with stress urinary incontinence (SUI) symptoms. The first exam was performed without the electrode, the second with the electrode inserted into the vagina, but with the stimulator switched off and the third with the stimulator turned on. We used the INNOVA (Empi) stimulator with electrical parameters set at 50 Hz and 60 mA and on an intermittent cycle during the cystometries and a continuous stimulation during the UPP. The data of functional profile length (FPL), maximum urethral closure pressure (MUCP), and area of the resting UPP, as well as the filling sensations and its respective bladder volumes during the cystometries, were compared. With regard to the cystometries. RESULTS: No effect of the electrode was observed on cystometry. However, the simple presence of the electrode improved the FPL, MUCP, and areas of the UPP similar to those when the stimulation was applied. CONCLUSIONS: We conclude that, the presence of the intravaginal electrode induces changes in the UPP not related to the stimulation itself. The physiotherapeutic effect of the electrode itself is still to be evaluated. 相似文献
1000.
Photochemical properties of ofloxacin involved in oxidative DNA damage: a comparison with rufloxacin
Cuquerella MC Boscá F Miranda MA Belvedere A Catalfo A De Guidi G 《Chemical research in toxicology》2003,16(4):562-570
Photodegradation of ofloxacin (OFX) under aerobic conditions gives rise to N-demethylation, mainly involving coupling of radical cation OFX(*)(+ )()with superoxide radical anion. Although H(2)O(2) is produced as a byproduct, oxidative damage to DNA to give 8-OH-dGuo is associated with a type II mechanism. When the photosensitizing potentials of OFX and rufloxacin (RFX) are compared under the same conditions, the latter is shown to produce a much higher degree of DNA oxidation despite the close structural similarity. This is explained by a decrease of the triplet energy when sulfur instead of oxygen is attached to position 8 of the fluoroquinolone ring system. As a consequence, phosphate anions are able to quench OFX triplet but not RFX triplet; this reveals that the reaction medium has a strong influence on the photochemistry of OFX and hence on its photobiological properties. 相似文献