Pressure Regulated Volume Control (PRVC): Set it and forget it?

Pressure-regulated volume control (PRVC) is a mode of ventilation in which the ventilator attempts to achieve set tidal volume at lowest possible airway pressure. This mode of ventilation is being commonly used as the initial mode of ventilation in many intensive care units. We describe two cases where this adaptive mode of ventilation became maladaptive leading to patient-ventilator dyssynchrony.

The Use of Portal Vein Pulsatility to Differentiate Hypervolemic and Hypovolemic Hyponatremia.

Hypotonic hyponatremia is a common electrolyte disorder defined by a blood serum sodium value of less than 136 meq/L. A challenge in managing hyponatremia is accurately determining the etiology for the free water excess as management can markedly differ. Accurate diagnosis of the etiology of hypotonic hyponatremia requires precision in the determination of extracellular volume status. Determination of volume status has traditionally relied on physical examination, imaging modalities, and clinical gestalt, all of which are inaccurate. Portal vein pulsatility is an easy to perform bedside ultrasound imaging study which can be used as a marker for hypervolemia and venous congestion. We present 2 cases of hypervolemic hyponatremia in which portal vein pulsatility was used in the diagnosis and management and as a marker for efficacy of treatment.