A 63-year-old man is hospitalized with dyspnea due to right lower lobe pneumonia. On the third day of hospitalization, he develops progressive respiratory failure and bilateral lung infiltrates. His trachea was intubated and mechanical ventilation is initiated. His blood pressure is 146/80 mm Hg, and pulse is 97/min. The patient's pulse oximetry shows 89% on assist-control mode with tidal volumes of 450 mL, respiratory rate of 30/min, fraction of inspired oxygen of 100%, and positive end-expiratory pressure of 12 cm H₂O. Examination shows diffuse crackles all over the lung fields, normal first and second heart sounds, and capillary refill of

Question

A 63-year-old man is hospitalized with dyspnea due to right lower lobe pneumonia. On the third day of hospitalization, he develops progressive respiratory failure and bilateral lung infiltrates. His trachea was intubated and mechanical ventilation is initiated. His blood pressure is 146/80 mm Hg, and pulse is 97/min. The patient's pulse oximetry shows 89% on assist-control mode with tidal volumes of 450 mL, respiratory rate of 30/min, fraction of inspired oxygen of 100%, and positive end-expiratory pressure of 12 cm H₂O. Examination shows diffuse crackles all over the lung fields, normal first and second heart sounds, and capillary refill of < 2 seconds. There is trace pre-sacral edema. Laboratory results are as follows: His chest-x ray reveals dense bilateral alveolar opacities. Bedside echocardiogram shows left ventricular ejection fraction of 65%. A central line is placed and the central venous pressure is 10 mm Hg. Conservative fluid management using diuretic therapy in this patient is most likely to positively affect which of the following?

Quizplus · Accepted Answer

11ec193a_9718_dfc9_853d_5bc99d9ed899_MD0002_00 This patient's presentation is consistent with acute respiratory distress syndrome (ARDS). Pulmonary edema in acute lung injury is dependent mainly on the quantity of intravascular hydrostatic pressure as oncotic pressure is unable to retain fluid in the capillaries. As a result, pulmonary edema can develop more easily in ARDS patients at any given hydrostatic pressure. Fluid restriction can decrease the risk of developing pulmonary edema. Studies have shown that conservative management with fluid restriction and diuretics is more effective in hemodynamically stable patients, as shown in the figure. Conservative management improved oxygenation index, and lung injury score (comprised of PaO₂/FiO₂ ratio, number of quadrants of infiltrates on chest x-ray, PEEP, and lung compliance). It resulted in fewer days on the ventilator and in the intensive care unit (Choice E). There was no significantly increased incidence of shock or renal failure (Choice D). In addition, there was no significant change in mortality in the hospital or oxygen saturation in mixed venous blood (Choices A and B). This patient appears hemodynamically stable and would benefit from conservative fluid management with diuretics given his high central venous pressure (CVP). (Choice C) Residual lung function was not measured in the fluid management studies of ARDS patients. Educational objective: Patients with acute lung injury and adequate perfusion should receive conservative fluid management that targets a CVP of < 4 mm Hg or a pulmonary artery occlusion pressure of < 8 mm Hg. Although this target is difficult to achieve, conservative fluid management results in improved oxygenation index and more ventilator-free days. __________ References: Comparison of two fluid-management strategies in acute lung injury. (http://www.ncbi.nlm.nih.gov/pubmed/16714767)

A 63-Year-Old Man Is Hospitalized with Dyspnea Due to Right