Traumatic brain injury (TBI) makes the brain susceptible to secondary insults such as ischemia. This study tested the hypothesis that L-arginine would increase regional CBF (rCBF) and brain tissue po2 (PbtO2) at the injury site.
A secondary insult model was employed in rodents. rCBF was measured with laser doppler flowmetry (LDF) and PbtO2 with a po2 catheter at the impact site. Animals were randomized to receive L-arginine, D-arginine or saline intravenously, 5 minutes after impact.
In animals who received L-arginine, the percentage rCBF from baseline (%CBF) was higher at the impact site after impact (p < 0.001), during bilateral carotid occulation (BCO) (p = 0.001) and during reperfusion (p = 0.032). In contrast, PbtO2 was not significantly increased throughout the experiment for the L-arginine group.
Administration of L-arginine increased rCBF in the injured brain tissue, and resulted in better preservation of CBF during BCO than D-arginine and saline.
From the Departments of Pediatrics/Emergency Medicine (D.R.M.) and Neurosurgery (L.C., C.S.R.), Baylor College of Medicine, Houston, Texas.
Submitted for publication January 23, 2003.
Accepted for publication October 10, 2003.
This work was supported by NIH grant #PO1-NS27616.
Abstract presented orally at The National Pediatric Academic Societies Conference, Baltimore, MD, April 2001, and orally at The National Society of Academic Emergency Medicine Conference, Atlanta, GA, May 2001.
Address for reprints: Donna Mendez, MD, Baylor College of Medicine, Pediatric Emergency Medicine, 6621 Fannin St. Room A210, Houston, TX 77030; e-mail: email@example.com.