Comparison of two pharmacological prophylaxis strategies for venous thromboembolism in spinal cord injury patients: a retrospective study.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To compare the cost and incidence of venous thromboembolism (VTE) and bleeding between two different VTE pharmacological prophylaxis strategies in individuals with spinal cord injury: one based on motor impairment (Protocol 1) and the other based on time from the lesion and presence of associated risk factors for VTE (Protocol 2). SETTING: A tertiary rehabilitation hospital in Brazil. METHODS: We retrospectively reviewed a total of 1475 charts of individual admissions: 814 individuals received pharmacological prophylaxis according to Protocol 1 and 661 according to protocol 2. These cohorts were compared with respect to age, time and level of injury, length of stay, AIS classification, type of injury, and occurrence of VTE and major bleeding. The number of prescribed doses of enoxaparin and expenditures associated with enoxaparin during each period were evaluated. RESULTS: The median lesion time was 3 years. The risk-based strategy drastically reduced the average monthly use of enoxaparin by 75% and the 12-month enoxaparin expenditure by $119,930.33, without increasing the risk of VTE. The incidence density of thromboembolic events was 0.55/10,000 patient-days, and all events occurred in individuals receiving prophylaxis according to Protocol 1. CONCLUSIONS: Time from injury and risk of VTE-based protocol for indication of pharmacological prophylaxis drastically reduced costs. No difference in occurrence of VTE was observed.

ABPM in COPD patients with sleep desaturation.

BACKGROUND: Sleep hypoxemia may change blood pressure by sympathetic activation. Few studies have analyzed blood pressure parameters in COPD patients who do not present sleep apnea, but do present sleep desaturation. OBJECTIVES: To analyze blood pressure parameters in COPD patients with sleep desaturation not caused by apnea. METHODS: Thirteen patients with COPD underwent spirometry, blood gas, polysomnography and ABPM for blood pressure evaluation. Fourteen patients without COPD underwent spirometry, oximetry and ABPM. Blood pressure analyses were carried out both during wakefulness and sleep. Both groups were comprised of patients with no history of hypertension. RESULTS: The two groups were similar as regards age, height, weight, and body mass index. A significant difference (p<0.05) was found between blood pressure levels during the wakefulness, sleep, 24-hour and sleep dip periods. Higher blood pressure levels were observed in patients with COPD, except for diastolic levels during wakefulness and maximum values during sleep and in the 24 hours. Sleep dip in the COPD group was attenuated, whereas physiological dip was observed in the control group, with lower blood pressure levels. CONCLUSIONS: Systolic and diastolic blood pressure levels in the COPD group were higher than those of the control group, with a significant difference found for all periods studied, except for diastolic levels during wakefulness and in the 24 hours. We can conclude that the group of COPD patients with sleep desaturation has significantly higher blood pressure levels than the control group.

Stability of the animal model of oleic acid-induced acute lung injury.

OBJECTIVE: To evaluate the stability of hemodynamic, respiratory and gas exchange variables in an animal model of oleic acid-induced acute lung injury. METHODS: This was an experimental study involving 10 mongrel dogs. The variables were measured at baseline, as well as at 30, 60, 90 and 120 min after the administration of oleic acid. In order to analyze repeated measurements, linear and quadratic effects were tested. Mixed linear models with diversified variance and covariance structures were used, depending on the variable studied. RESULTS: We found that mean arterial blood pressure stabilized at 30 min, as did heart rate, pulmonary arterial pressure and pulmonary capillary pressure at 60 min. Respiratory rate, tidal volume, minute volume and respiratory work stabilized at 30 min. Regarding gas exchange variables, PaO2, PaO2/FiO2 ratio and pulmonary shunt fraction stabilized at 30 min. The remaining variables maintained a continuous rise or fall. CONCLUSIONS: This oleic acid-induced acute lung injury model is stable for some of the variables tested, although stabilization occurs at different times. The respiratory and gas exchange variables stabilized at 30 min, whereas the hemodynamic variables stabilized at 60 min.

The influence of lung function and muscular strength on the functional capacity of chronic obstructive pulmonary disease patients.

AIM: To determine which variable (forced expiratory volume in 1 second (FEV1), partial pressure of oxygen in arterial blood (PaO2), nocturnal hypoxaemia and muscular strength of femoral quadriceps) can predict the distance walked in the six-minute walk test (6MWT) by COPD patients. METHODS: A cross-sectional and observational study of thirty patients referred to a pulmonary rehabilitation programme at a university hospital. Lung function was evaluated by spirometry, arterial blood gas analysis and nocturnal oximetry. Muscle function was evaluated by quadriceps strength and functional capacity by the 6MWT. RESULTS: Bivariate regression analysis showed that quadriceps strength, was the only variable to correlate significantly with the distance walked in the 6MWT (p=0.002), accounting for 38% of the 6MWT variance. The statistical relationship established for these variables was 1kg of quadriceps strength equalled 5.9 metres walked in the 6MWT. CONCLUSIONS: Our results showed the importance of lower limb muscle strength in submaximal exercise testing. We conclude that femoral quadriceps muscle strength is the only one of the variables studied which can predict the distance COPD patients walk in the 6MWT.

Correlation between mild hypoxaemia and limb skeletal muscle function in chronic obstructive pulmonary disease - pilot study.

RATIONALE: Exercise capacity in COPD patients depends on the degree of airflow obstruction, the severity of the hypoxaemia and skeletal muscle function. Muscle atrophy and weakness are considered systemic consequences of COPD and are associated with reduced exercise capacity. AIMS: To investigate the correlation between mild hypoxaemia and muscular strength, muscular fatigue and functional capacity in COPD patients. METHODS: Ten patients enrolled on a PRP at the Hospital Universitário de Brasília - HUB were included in this study. Lung function was evaluated by spirometry and arterial blood gas analysis. Functional evaluation was made using the 6MWT and using isometric contraction of deltoid and quadriceps muscles. RESULTS: There were positive correlations between PaO2, quadriceps strength (r2 = 0.61 and p = 0.007) and PaO2 and the 6MWT (r2 = 0.96, p = 0.001). There were negative correlations between PaO2 and median frequency of quadriceps (r2 = -0.42 and p = 0.04). We observed significant correlation between quadriceps strength and the 6MWT (r2 = 0.67 and p = 0.001). There was negative correlation between median frequency of quadriceps and the 6MWT (r2 = -0.42 and p = 0.04). We did not observe any correlation between PaO2 and strength or median frequency of deltoid muscle. CONCLUSIONS: PaO2 has important correlations with muscular function variables. The main negative impact of mild hypoxaemia and precocious limb muscular disability on COPD patients is decreased functional capacity.