Chest
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The mortality rate among patients with human immunodeficiency virus (HIV) requiring mechanical ventilation (MV) for acute respiratory failure (ARF) secondary to Pneumocystis carinii pneumonia (PCP) is still a matter of discussion. For some authors, it is in the 50 percent range, while for others the prognosis is grim, with virtually no survivors. The aim of this retrospective study conducted between January 1987 and January 1992 was to analyze the outcome of such patients. ⋯ The interval between treatment and MV was 8.1 +/- 6.5 days and the duration of MV was 11.4 +/- 9.9 days. The patients were classified into 3 groups on the basis of the duration and type of treatment before MV, as follows: group 1, n = 10: TMP-SMZ (20-100 mg/kg) IV and methylprednisolone (MP) < 5 days before MV; group 2, n = 4: TMP-SMZ > or = 5 days and MP < 5 days; group 3, n = 19: TMP-SMZ and MP > or = 5 days before MV. (The MP dose was as follows: 240 mg/d once a day from day 1 to day 3; 120 mg/d from day 4 to day 6; and 60 mg/d from day 7 to day 9.) Despite MV, TMP-SMZ, and MP, death secondary to PCP-related ARF occurred in 81.9 percent of patients, 20 +/- 4.8 days after the beginning of treatment and 11.4 +/- 9.9 days after the beginning of MV. Six patients survived, five in group 1 and one in group 3.(ABSTRACT TRUNCATED AT 400 WORDS)
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Oxygen consumption (VO2) has been shown to be decreased after acute myocardial infarction (AMI) complicated by cardiogenic shock. ⋯ VO2 is increased in UAMI and represents increased metabolic demands of peripheral tissues and not cardiac oxygen uptake. A reduction in VO2 (< 100 ml/min.m2) after AMI may be an early predictor of subsequent development of cardiogenic shock. Measurement of VO2 in UAMI by indirect calorimetry in the emergency department may be of value to identify patients at high risk and could influence their management.
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Cardiopulmonary failure resulting from progression of obstructive sleep apnea (OSA) is treated with endotracheal intubation and mechanical ventilation. This study was conducted to determine whether the use of nasal continuous positive airway pressure (CPAP) would rapidly reverse changes in mental status and hypercapnic acidosis in such patients with decompensated hypercapnic respiratory failure resulting from OSA. Six morbidly obese patients (mean weight, 159 +/- 19 kg) were treated with nasal CPAP and supplemental oxygen. ⋯ None of the patients required intubation and mechanical ventilation. There were no complications attributable to the CPAP delivered by nasal mask. We conclude that CPAP delivered by nasal mask can be safe and effective in rapidly reversing changes in mental status and hypercapnic acidosis in this group of patients with severe respiratory failure, and nasal CPAP obviates the need for endotracheal intubation and mechanical ventilation.
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The effects of Carbicarb, sodium bicarbonate, and sodium chloride on arterial blood gases, lactate concentrations, hemodynamics, and myocardial intracellular pH were compared in hypoxic lactic acidosis with controlled carbon dioxide elimination. Twenty-one young mongrel dogs were anesthetized, mechanically ventilated, and randomly allocated into one of three treatment groups. After hypoxic lactic acidosis was induced and maintained, 2.5 mEq/kg of one of the agents was infused over 30 min. ⋯ Stroke volume index was also increased significantly with decreased heart rate. The data suggest that Carbicarb administration in hypoxic lactic acidosis improved hemodynamics compared with sodium bicarbonate or sodium chloride administration. The increased stroke volume and cardiac contractility appear to be due to improved myocardial intracellular pH.
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Major surgery in the elderly continues to have a high mortality rate. Preoperative myocardial ischemia is a known risk factor. Cardiac failure is also a risk factor, but is difficult to quantify objectively. ⋯ A low AT associated with preoperative ischemia resulted in the death of 8 of 19 patients, a mortality rate of 42 percent. When the ischemia was associated with the higher AT, then 1 patient out of 25 died, a mortality rate of 4 percent (p < 0.01). Both preoperative ischemia and preoperative cardiac failure are independent risk factors for perioperative mortality in the elderly.