Testing preload responsiveness by the tidal volume challenge assessed by the photoplethysmographic perfusion index.

Background: To detect preload responsiveness in patients ventilated with a tidal volume (Vt) at 6 mL/kg of predicted body weight (PBW), the Vt-challenge consists in increasing Vt from 6 to 8 mL/kg PBW and measuring the increase in pulse pressure variation (PPV). However, this requires an arterial catheter. The perfusion index (PI), which reflects the amplitude of the photoplethysmographic signal, may reflect stroke volume and its respiratory variation (pleth variability index, PVI) may estimate PPV.

The Effect of Positive End-Expiratory Pressure on Pulmonary Vascular Resistance Depends on Lung Recruitability in Patients with Acute Respiratory Distress Syndrome.

A U-shaped relationship should exist between lung volume and pulmonary vascular resistance (PVR), with minimal PVR at FRC. Thus, positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) should increase PVR if it induces significant lung distension compared with recruitment. However, this has never been proved in patients.

Clinical significance of thrombocytopenia in patients with septic shock: An observational retrospective study.

Purpose: Whether thrombocytopenia in critically ill patients accounts for a bystander of severity or drives specific complications is unclear. We addressed the effect of thrombocytopenia on septic shock, with emphasis on intensive care unit (ICU)-acquired bleeding, infections and thrombotic complications.

Materials And Methods: A retrospective (2008-2019) single-center study of patients with septic shock.