The effect of total spinal anesthesia on cardiac function in a large animal model of brain death.
Brain death (BD) causes cardiac dysfunction in organ donors, attributable to the catecholamine storm that occurs with raised intracerebral pressure (ICP). However the direct contribution of the spinal sympathetics has not been well described. We examined the effect of total spinal anesthesia (TSA) on cardiac function in a large animal model of BD. Eighteen pigs were allocated to 3 experimental groups: Group 1, the saline-treated control group; Group 2, TSA administered prior to BD; and Group 3, TSA administered 30 min after BD. Inflation of an intracerebral balloon-tipped catheter was used to induce BD. Ventricular function was assessed using a pressure-volume loop catheter and magnetic resonance imaging. Serum catecholamine levels were assessed with high performance liquid chromatography. Inflation of the intracerebral balloon-tipped catheter was associated with a dramatic rise in heart rate and blood pressure, along with increased concentrations of serum epinephrine and norepinephrine. This phenomenon was not observed in Group 2. In Group 1, there was a significant decline in contractility, whereas groups 2 and 3 saw no change. Group 2 had greater contractile reserve than groups 1 and 3. Our data demonstrate the central role of spinal sympathetics in the hemodynamic response to raised ICP. Further work is required to determine the utility of TSA in reversing cardiac dysfunction in BD donors.
Department of Anesthesia, Surgery, Physiology and Pathology, University of Manitoba, St. Boniface Hospital, Winnipeg, Canada.
Waiel A
WA
Almoustadi
Trevor W R
TW
Lee
Julianne
J
Klein
Kanwal
K
Kumar
Rakesh C
RC
Arora
Ganghong
G
Tian
Darren H
DH
Freed
D000775:Anesthesia, Spinal; D000818:Animals; D001926:Brain Death / Q000503:physiopathology*; D004195:Disease Models, Animal; D005260:Female; D006321:Heart / Q000502:physiology*; D016027:Heart Transplantation; D019028:Magnetic Resonance Imaging, Cine; D034421:Sus scrofa; D014019:Tissue Donors; D016277:Ventricular Function, Left / Q000502:physiology