CURRENT Essentials of Critical Care.pdf

Chapter 5 Fluids, Electrolytes, & Acid-Base 63■■■HypervolemiaEssentials of Diagnosis• Increase in extracellular volume: generalized or localized to certaincompartments• Peripheral dependent pitting edema• Ascites with abdominal distention• Pulmonary edema or pleural effusions with dyspnea, rales,wheezes; resulting hypoxemia causing peripheral cyanosis, respiratoryfailure, altered mentation• Can be associated with decreased, normal or increased “effective”intravascular volumeDifferential Diagnosis• Congestive heart failure• Liver cirrhosis with ascites• Pre- and posthepatic portal hypertension with ascites• Nephrotic syndrome• Protein-losing enteropathy• Excess sodium intake: hypertonic solutions, dietary sources• Renal failure with oliguria• Hyperaldosteronism and hypercortisolismTreatment• Treatment depends on mechanism of disease• Diuretics mainstay of therapy• In reduced effective intravascular volume: delay diuresis untilintravascular fluid deficit corrected; some worsening of hypervolemiaacceptable during fluid resuscitation• Dietary sodium and fluid restriction• Large volume paracentesis or thoracentesis for symptom relief• Oxygen supplementation• Cardiogenic pulmonary edema: morphine, vasodilators (nitroprusside,hydralazine, ACE inhibitors), venodilators (nitrates),inotropes• Ventilatory support: mechanical or noninvasive ventilation• Hemodialysis or ultrafiltration in refractory cases■ PearlThe common practice of renal-dose dopamine to induce diuresis hasfailed to be supported by the literature.ReferenceKreimeier U: Pathophysiology of fluid imbalance. Crit Care 2000;4:S3. [PMID:11255592]