Research

N-acetylcysteine decreases lactate signal intensities in liver tissue and improves liver function in septic shock patients, as shown by magnetic resonance spectroscopy: extended case report

Ortrud Vargas Hein¹, Renate Öhring², Andreas Schilling², Michael Oellerich³, Victor W Armstrong³, Wolfgang J Kox¹ and Claudia Spies¹

¹Department of Anesthesiology and Intensive Care Medicine Charité, Campus Mitte, Humboldt University Berlin, Germany

²Department of Neurology, Benjamin Franklin Medical Center, Free University Berlin, Germany

³Department of Clinical Chemistry, Georg-August University Göttingen, Germany

author email corresponding author email

Critical Care 2004, 8:R66-R71

Published:	22 January 2004

See related Commentary: http://ccforum.com/content/8/2/93

Abstract

Background

N-acetylcysteine (NAC) has been shown to improve splanchnic blood flow in experimental studies. This report evaluates the effects of NAC on liver perfusion and lactate signal intensities in the liver tissue of septic shock patients using proton magnetic resonance imaging and spectroscopy. Furthermore, the monoethylglycinexylidide (MEGX) test was used to investigate hepatic function.

Methods

Five septic shock patients received 150 mg/kg body weight NAC as an intravenous bolus injection over 15 min. Lidocaine was injected both prior to and following NAC administration in order to determine MEGX formation. Measurements (hemodynamics, oxygen transport-related variables, blood samples for lactate, liver-related markers) were performed 1 hour before and 1 hour after NAC injection. In addition to the proton magnetic resonance imaging patients received two proton magnetic resonance spectra, one prior to and one 30 min subsequent to the onset of the NAC infusion at a 1.5 Tesla clinical scanner, for measurement of liver perfusion and liver lactate signal intensity.

Main findings

Following NAC infusion, the lactate signal intensity in the liver tissue showed a median decrease of 89% (11–99%), there was a median increase in liver perfusion of 41% (-14 to 559%), and the MEGX serum concentration increased three times (1.52–5.91).

Conclusions

A decrease in the lactate signal intensity in the liver tissue and an increase in the MEGX serum concentration and in liver perfusion might indicate improved liver function as a result of NAC administration. Patients with compromised hepatosplanchnic function, such as patients with septic shock due to peritonitis, may therefore benefit from NAC therapy.