Elevation of Plasma Renin Activity, Angiotensins I and II, and Aldosterone in Burn Patients: Na+/Volume-Responsive But not Dependent

摘要

THE ACTIVITY OF physiologic responses instrumental in central volume restoration is greatly enhanced subsequent to injury. Controlled surgical trauma exaggerates solute and water retention, and mechanism(s) mediating this response manifest volume sensitivity. In the present investigation, we studied responsiveness of plasma renin activity (PRA), angiotensins I and II (Al and AII), and plasma aldosterone (PA) to exogenous sodium (Na(+)) administration in thermally injured subjects. Paralleling previous studies (5) from this laboratory showing elevated visceral (including renal) blood flow in burn patients, the present findings show elevated CRCL and circulating PRA, AI, AII, and PA in burns. Elevation of these hormones does not appear to be dependent on effective volume deficit. Nevertheless, concentrations of these hormones remain sodium-and/or volume-responsive, suggesting a resetting of hormonal control mechanism(s) as a result of thermal trauma.