Critical care medicine
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To evaluate the use of serum lactic acid values to predict flow-dependent increases in oxygen consumption (VO2) in response to increasing oxygen delivery (DO2) after blood transfusion in surgical sepsis. ⋯ Blood transfusion can be used to augment DO2 and VO2 in septic surgical patients. Increased serum lactic acid values do not predict patients who will respond. The absence of lactic acidosis should not be used in this patient population to justify withholding blood transfusions to improve flow-dependent VO2. Patients who have increased lactate concentrations may have a peripheral oxygen utilization defect that prevents improvement in VO2 with increasing DO2.
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Critical care medicine · Mar 1991
Comparative StudyAcute airway injury during high-frequency jet ventilation and high-frequency oscillatory ventilation.
We compared tracheal histologic injury patterns, airway pressure (Paw) requirements, and in vivo and in vitro estimate of airway humidification in 13 adult cats with normal lungs mechanically ventilated for 16 hr. Six animals were treated with high-frequency jet ventilation at 400 breaths/min and seven animals with high-frequency oscillatory ventilation at 900 breaths/min. ⋯ In this animal model, high-frequency ventilation using either jet or oscillation techniques produced similar inflammatory tracheal damage despite differences in Paw exposure and humidity.
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Critical care medicine · Mar 1991
Comparative StudyAge effects susceptibility to pulmonary barotrauma in rabbits.
We studied the effect of age on the development of pulmonary barotrauma after mechanical ventilation with high peak inspiratory pressures (PIP). ⋯ These data indicate that the lungs of young rabbits had a higher baseline microvascular permeability and were more susceptible to the development of ventilator-induced increased microvascular permeability. More compliant lungs and chest wall and the larger distending volumes attained at each peak airway pressure appear to be the mechanisms.