Exposure to high altitude induces pulmonary hypertension that may lead to life-threatening conditions. In a randomized, double-blind, placebo-controlled study, the effects of oral sildenafil on altitude-induced pulmonary hypertension and gas exchange in normal subjects were examined. Twelve subjects (sildenafil [SIL] n = 6; placebo [PLA] n = 6) were exposed for 6 days at 4,350 m. Treatment (3 x 40 mg/day) was started 6 to 8 hours after arrival from sea level to high altitude and maintained for 6 days. Systolic pulmonary artery pressure (echocardiography) increased at high altitude before treatment (+29% versus sea level, p < 0.01), then normalized in SIL (-6% versus sea level, NS) and remained elevated in PLA (+21% versus sea level, p < 0.05). Pulmonary acceleration time decreased by 27% in PLA versus 6% in SIL (p < 0.01). Cardiac output and systemic blood pressures increased at high altitude then decreased similarly in both groups. Pa(O(2)) was higher and alveolar-arterial difference in O(2) lower in SIL than in PLA at rest and exercise (p < 0.05). The altitude-induced decrease in maximal O(2) consumption was smaller in SIL than in PLA (p < 0.05). Sildenafil protects against the development of altitude-induced pulmonary hypertension and improves gas exchange, limiting the altitude-induced hypoxemia and decrease in exercise performance.

In patients undergoing partial ventilatory support, with clinical and electromyographic signs of increased respiratory muscle loading, ASV provided levels of minute ventilation comparable to those of SIMV-PS. However, with ASV, central respiratory drive and sternocleidomastoid activity were markedly reduced, suggesting decreased inspiratory load and improved patient-ventilator interactions. These preliminary results warrant further testing of ASV for partial ventilatory support.

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Using a noninvasive, continuous technique to estimate cardiac sympathovagal balance, no significant variation in autonomic balance induced by spinal anesthesia was observed. However, untoward episodes of bradycardia and hypotension occurred in three patients, who could not be prospectively identified by the parameters studied.

A significant correlation was observed between predicted values of V'ti/V'peak and those values measured in patients undergoing pressure support. These findings should stimulate further research into the possible applications of this mathematical model to optimize expiratory trigger setting. Furthermore, our findings suggest that expiratory trigger should be adjustable and provide a wider range of cutoff levels than that which is currently available.

These results confirm that the baroreflex sensitivity is depressed in end-stage liver disease in line with an autonomic nervous system imbalance. The liver transplantation reverses this disturbance only in some patients.

This pilot study suggests that increasing tacrolimus dosage could be considered as treatment against early acute rejection episodes including the severe grade.

We describe the first association between Hodgkin’s lymphoma and Wegener’s granulomatosis, heralded by renal involvement. A 43-year-old man developed rapidly progressive glomerulonephritis requiring chronic hemodialysis 8 months after remission of Hodgkin’s lymphoma. At that moment, no extrarenal involvement was found, despite extensive investigation. Antineutrophil cytoplasm antibodies were positive, without specificity for proteinase-3 or myeloperoxydase. Six months after beginning hemodialysis, multiple pulmonary nodules appeared, along with rapid clinical worsening. A surgical biopsy was performed which disclosed a giant cell granuloma. Antimyeloperoxydase antibodies remained negative, whereas proteinase-3 antibodies became positive. Wegener’s granulomatosis was diagnosed and treatment with cyclophosphamide and steroids was started. Clinical and radiological improvement occurred promptly. Eleven months after treatment, both Wegener’s disease and Hodgkin’s lymphoma remained in remission.