Augmented Renal Clearance in Traumatic Brain Injury: A Single-Center Observational Study of Atrial Natriuretic Peptide, Cardiac Output, and Creatinine Clearance.
Augmented renal clearance (ARC) is being increasingly described in neurocritical care practice. The mechanisms driving this phenomenon are largely unknown. The aim of this project was therefore to explore changes in renal function, cardiac output (CO), and atrial natriuretic peptide (ANP) concentrations in patients with isolated traumatic brain injury (TBI). This prospective observational cohort study was conducted in a tertiary-level, university-affiliated intensive care unit (ICU). Patients with normal plasma creatinine concentrations (<120 μmol/L) at admission and no history of chronic kidney disease, admitted with isolated TBI, were eligible for enrollment. Continuous CO measures were obtained using arterial pulse waveform analysis. Eight-hour urinary creatinine clearances (CLCR) were used to quantify renal function. ANP concentrations in plasma were measured on alternate days. Data were collected from study enrollment until ICU discharge, death, or day 15, which ever came first. Eleven patients, contributing 100 ICU days of physiological data, were enrolled into the study. Most participants were young men, requiring mechanical ventilation. Median ICU length of stay was 9.6 [7.8-13.0] days. Elevated CLCRmeasures (>150 mL/min) were frequent and appeared to parallel changes in CO. Plasma ANP concentrations were also significantly elevated over the study period (minimum value = 243 pg/mL). These data suggest that ARC is likely to complicate the care of TBI patients with normal plasma creatinine concentrations, and may be driven by associated cardiovascular changes and/or elevated plasma ANP concentrations. However, significant additional research is required to further understand these findings.
1 Department of Intensive Care and Hyperbaric Medicine, The Alfred , Prahran, VIC, Australia .|2 School of Public Health and Preventive Medicine, Faculty of Medicine, Nursing, and Health Sciences, Monash University , The Alfred Center, Prahran, VIC, Australia .
Andrew A
AA
Udy
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Paul
P
Jarrett
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Melissa
M
Lassig-Smith
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Janine
J
Stuart
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Therese
T
Starr
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Rachel
R
Dunlop
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Renae
R
Deans
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .|4 Pharmacy Department, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .|5 Burns, Trauma, and Critical Care Research Center, The University of Queensland , Herston, QLD, Australia .
Jason A
JA
Roberts
6 The Townsville Hospital Intensive Care Unit , 2nd Floor North Block, The Townsville Hospital, Douglas, QLD, Australia .
Siva
S
Senthuran
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .
Robert
R
Boots
7 Heart Foundation Research Center, Menzies Health Institute Queensland, Griffith University , Gold Coast, QLD, Australia .
Kavita
K
Bisht
7 Heart Foundation Research Center, Menzies Health Institute Queensland, Griffith University , Gold Coast, QLD, Australia .
Andrew C
AC
Bulmer
3 Department of Intensive Care Medicine, Royal Brisbane and Women's Hospital , Herston, QLD, Australia .|5 Burns, Trauma, and Critical Care Research Center, The University of Queensland , Herston, QLD, Australia .
Jeffrey
J
Lipman
D000328:Adult; D009320:Atrial Natriuretic Factor / Q000097:blood*; D000070642:Brain Injuries, Traumatic / Q000097:blood* / Q000000981:diagnostic imaging / Q000503:physiopathology; D002302:Cardiac Output / Q000502:physiology*; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood*; D005260:Female; D006801:Humans; D007668:Kidney / Q000378:metabolism*; D008297:Male; D008657:Metabolic Clearance Rate / Q000502:physiology*; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult
D009320:Atrial Natriuretic Factor; D003404:Creatinine
biomarkers; clinical management of CNS injury; traumatic brain injury