Biomedical subjects

I Boaventura

Publications and source records attributed to I Boaventura.

7 recordsLinked to original sources

PubMed1995

Influence of non-steroidal anti-inflammatory drugs on renal function and 24h ambulatory blood pressure-reducing effects of enalapril and nifedipine gastrointestinal therapeutic system in hypertensive patients.

OBJECTIVE: To evaluate the influence of non-steroidal anti-inflammatory drugs (NSAIDs; aspirin and indomethacin) on the renal and antihypertensive effects of enalapril and nifedipine gastrointestinal therapeutic system (GITS) in patients with essential hypertension. DESIGN AND METHODS: In a crossover study, 18 patients on an unrestricted-salt diet were randomly assigned to receive either enalapril (20-40 mg/day) or nifedipine-GITS (30-60 mg/day) for 4-8 weeks, followed by aspirin (100 mg/day for 2 weeks) and then indomethacin (75 mg/day for 1 week). Blood pressure was measured by 24h ambulatory monitoring. RESULTS: Enalapril and nifedipine-GITS significantly reduced blood pressure compared with placebo. Aspirin did not alter the antihypertensive effect of either drug. Indomethacin attenuated (by 45%) the antihypertensive effect of enalapril throughout the 24h period of evaluation, but did not interfere with the effect of nifedipine. Furthermore, indomethacin significantly reduced the fractional excretion of sodium and plasma levels of prostaglandins in a similar way when added to either the enalapril or the nifedipine regimen. CONCLUSIONS: Vasodilatory prostaglandins are probably involved in the antihypertensive effects of enalapril but not of nifedipine, and this interaction seems to be independent of any indomethacin-induced decrease in renal sodium excretion. Nifedipine may be an appropriate drug to treat hypertensive patients requiring concomitant therapy with NSAID.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1994

[Compliance to therapy -- its importance in research and clinical practice].

Compliance, defined as patients behaviour to treatment schedule over time, specially in chronic diseases, is an important parameter to be measured in clinical trials. Compliance to a specific drug may compromise the final efficacy expected result assumed by phase I II and III studies. The medication events monitors systems (MEMS) appeared to get a more specific and sensitive measurement than the classic counting pills and drug or markers levels to analyses of compliance. The authors made a revision of literature in order to evaluate the benefits of compliance measurement in trials (specially hypertension as a paradigm of chronic disease) and clinical practice. Partial compliance with antihypertensive treatment could be an obstacle to an effective control or to demonstrate long term efficacy on decreasing morbidity and mortality. A short discussion is made about the possible benefits of using MEMS on clinical trials to evaluate patient's quality of life and behaviour to long term treatment for chronic diseases.

Clinical Medicine↗

PubMed1993

[Automatic measurement of arterial pressure].

Whenever we have a new technique for the measurement of Blood Pressure (BP), variations to standard devices should be expected. Recent guidelines for measurement and validation of automatic devices by Scientific Societies should be followed if doctors want to improve the accuracy of readings, avoiding mistakes in the diagnosis and monitoring of hypertension. To characterize the variability and reproducibility of the DINAMAP (Dynamic Automatic Mean Arterial Pressure), a random comparison with two observers (A; B) between this device and the sphygmomanometer was performed in a group of 80 patients with different pathologies. To evaluate the variability and reproducibility in the same person we analysed as well the mean variation in a setting of successive readings in 3 persons. The global correlation was good for both systolic (r = 0.9) and diastolic pressures. The behaviour of the DINAMAP for different pressure levels was obtained by the regression analyses of the pressures differences between both devices. The best correlation is found around the 140 mmHg measurements, pressures above or under this level are respectively underestimated and undervalued. We discuss the needs of a standard statistical methodology with physiological meaning for the analysis which enables to understand the multiple variations that doctors can find when performing the comparison tests.

Adult↗

PubMed1992

[Pulmonary embolism--mortality risk].

We conducted a retrospective analysis on 311 patients with clinical diagnosis of pulmonary embolism (PE) in a period of 3 years. 163 patients were excluded based on clinical-laboratorial criteria. The remaining 146 patients had a median age of 69 years (range: 30-91 years). 54% of the patients were male. We found dyspnea (94%), abnormal cardiopulmonary observation (89%), risk factors for venous thromboembolism (74%), tachycardia (53%), cyanosis (49%), and neck vein distension (45%) to be the most frequent findings. 64% of the patients had heart failure, 32% had myocardial ischemia, 13% had cancer, and 11% had myocardial infarction. Lactic dehydrogenase (LDH) was higher than two-fold in 54% of the patients. There was severe hypoxemia in 55% of the cases and hypocapnia in 43% of the cases. Creatinine phosphokinase (CPK) was elevated in 16% of the cases. Electrocardiography was suggestive of PE in 37% of the cases. Echocardiography showed right heart dysfunction in 30% of the cases, 92% of the patients were treated with heparin, 37 patients (25%) died, 54% of which during the first 4 days after admittance. Trying to define an index of mortality in PE we evaluated all patients by discriminant analysis coming up with 14 items with good discriminative power. By approximation of their odds-ratios we determined how many points would correspond to each item in the total sum.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[Determination of endoxin in hypertensive patients].

Digoxin like immunoreactive factor (DLIF), has been implicated on the effect of sodium in essential hypertension. The different concentration of DLIF as a function of sodium intake was demonstrated in animal experience by some authors. In this work the urinary DLIF excretion is evaluated by RIA and its biological activity by Na+/K+ ATPase inhibition, in 5 urine samples at the end of a free sodium diet week and in 10 urine samples in the last day of a week with 250 mg sodium diet. The urinary DLIF excretion after the free sodium diet week was 0.3460 +/- 0.055 and at the end of sodium restriction diet week of 0.2910 +/- 0.061 nmol/l. Although the DLIF values in the sodium restriction week were smaller than the DLIF values of the free sodium diet week, there was no statistical difference (p = 0.113). In five patients the DLIF could be evaluated at the end of the first and second weeks without changes in the hypertensive therapeutics, with clonidine and nifedipine, along the two weeks. In these five patients at the end of the free sodium diet week and at end of the sodium restricted diet week were 0.3460 +/- 0.055 and 0.2780 +/- 0.060 nmol/l. The reduction of urinary DLIF excretion in the sodium restricted diet week, was significative (p = 0.020). The results of the Na/K ATPase inhibition in the same five patients were: 34.6 +/- 6.51% at the end of the free sodium diet week and 31.7 +/- 6.32% at the end of the sodium restricted diet week, the differences were not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

[Automatic measurement of arterial pressure. A new method for analysis, quantification and evaluation of hypertensive disease].

The authors try to analyse the role of ambulatory 24 h blood pressure monitoring (ABP) in the diagnosis of hypertension, and review medical literature on this subject. They emphasized the quantification and definition value of normal results and circadian profiles in ABP. The accuracy of the device and the choice of a correct statistical parameter of prognosis is essential in all prospectives studies. In the future a better correlation is expected between blood pressure and organ damage when blood pressure is measured by ambulatory recordings then office method.

Blood Pressure Determination↗

PubMedDate not supplied

[Ambulatory monitoring of blood pressure. Validation of a method].

Before the routine use of our ambulatory blood pressure (ABP) device, we did the correlation analysis of 153 pairs of blood pressure measurements within the ABP and gold-standard sphygmomanometer. We got a good correlation but a systematic statistical error about less 7 mmHg on systolic measurement and 11 mmHg on diastolic measurement by the ABP device. The different qualities found among the devices that we have in the market, lead to the proposal of protocols of validation in the premarketing and periodic quality assessment by the clinics.

Blood Pressure Determination↗