L-arginine pathway in the sepsis syndrome : Critical Care Medicine (original) (raw)

Clinical Investigations: PDF Only

LORENTE, JOSÉ A. MD; LANDÍN, LUIS MD, PHD; DE PABLO, RAUL MD; RENES, EMILIO MD; LISTE, DAVID MD

From Unidades de Cuidados Intensivos, and the Hospital Universitario de Getafe (Dr. Lorente), Hospital Ramóny Cajal (Drs. Landín, de Pablo, and Liste), Hospital 12 de Octubre (Dr. Renes), Madrid, Spain.

Abstract

Objective

To investigate the role of nitric oxide in the regulation of vascular tone in patients with the sepsis syndrome.

Design

Prospective, intervention study.

Setting

Tertiary care hospital.

Patients

Fifteen patients admitted to our medical intensive care unit with the diagnosis of sepsis syndrome by defined criteria.

Interventions

Eight patients received Nω-nitro-L-arginine was followed by hypertension (mean blood pressure increased from 89 ± 8 to a maximum of 140 ± 12 mm Hg) accompanied by a decrease in cardiac index (from 3.51 ± 0.39 to a minimum of 2.65 ± 0.21 L/min/m2) and an increase in right atrial and pulmonary artery occlusion pressure. Systemic vascular resistance index increased from 1871.1 ± 302.3 to 3825.6 ± 244.4 dyne·sec/cm5·m2, and pulmonary vascular resistance increased from 533.2 ± 125.8 to 816.0 ± 117.3 dyne·sec/cm5·m2. These changes induced by Nω-nitro-L-arginine were reversed by the administration of L-arginine.

The administration of L-arginine to another group of patients caused transient hypotension (from 103 ± 6 to 81 ± 10 mm Hg) and an increase in cardic index (from 3.57 ± 0.15 to 4.74 ± 0.54 L/min/m2). Both systemic and pulmonary vascular resistance indices decreased (from 1987.6 ± 163.9 to 1251.4 ± 231.5 dyne·sec/cm5·m2, and from 486.1 ± 65.2 to 380.5 ± 70.3 dyne·sec/cm5·m2). Parallel to the increase in oxygen transport due to the increase in cardiac output, oxygen consumption index increased significantly 1 min after L-arginine (from 127.0 ± 19.0 to 182.5 ± 37.3 mL/min/m2). All mentioned changes were statistically significant (p<.05).

Conclusions

A continuous basal release of nitric oxide plays a role in the regulation of systemic and pulmonary vascular tone in patients with sepsis syndrome. L-arginine has systemic and pulmonary vasodilatory actions. (Crit Care Med 1993; 21:1287–1295)