Haemodynamic evaluation during small volume resuscitation in patients with acute respiratory failure

Abstract

In addition to the invasive haemodynamic monitoring procedures, an on-line assessment of cardiac performance by means of transoesophageal echocardiography might have a certain role in small volume resuscitation of patients with acute respiratory failure or Adult Respiratory Distress Syndrome (ARDS). The goal of this investigation was therefore to determine the effects of a hypertonic hyperoncotic solution, hypertonic hydoxyethl-starch (HHES), (HHES = HES [200.000/0.6-0.66; 60 g l-1; Leopold, Graz; Austria] combined with NaCl [75 g l-1) on haemodynamics and cardiac performance using the transoesophageal echocardiography. After institutional approval we investigated 23 patients suffering from septic ARDS after trauma or major surgery during four periods of resuscitation. Phase I = control values after infusion of 20 ml kg-1 crystalloid solution, phase II = 50% hypertonic hydroxyethyl-starch solution (2 ml kg-1), phase III = at the end of HHES (4 ml kg-1), IV = 30 min after the end of HHES. Before HHES-infusion, all patients showed arterial hypotension with mean arterial pressures of 64 +/- 2 mmHg. The infusion of 2 ml kg-1 HHES resulted in a significant increase of systemic and pulmonary arterial pressures over the study period. A significant improvement in cardiac output was associated with increasing stroke volumes, oxygen delivery and oxygen consumption (see Tables 1 and 2). Small volume resuscitation also resulted in significant increases of endsystolic and endiastolic left ventricular areas and the corresponding calculated wall stress (Figs 1-3). We conclude from our preliminary data that when using HHES, only modest fluid resuscitation was sufficient to restore adequate preload and oxygen delivery in patients with sepsis-related acute respiratory failure.