Changes in sympathetic outflow, and the associated cardiovascular effects, are well known to occur during refractory intracranial hypertension, uncal herniation and brainstem death. However, sympathetically mediated changes in renal perfusion and the cortical microcirculation, although hypothesised to occur, are not well documented. Using contrast enhanced ultrasound, the presented case demonstrates a dramatic improvement in, previously abnormal, renal blood flow following uncal herniation. These findings potentially illustrate the effect of sympathetic tone on organ perfusion and the microcirculation in critical illness. Future study in this area may have important implications on vasopressor and organ transplantation practices.
WatchornJHuangDBramhamK, et al.Decreased renal cortical perfusion, independent of changes in renal blood flow and sublingual microcirculatory impairment, is associated with the severity of acute kidney injury in patients with septic shock. Crit Care2022; 26: 261, https://link.springer.com/article/10.1186/s13054-022-04134-6 (2022).
4.
SchneiderAGGoodwinMDSchellemanA, et al.Contrast-enhanced ultrasound to evaluate changes in renal cortical perfusion around cardiac surgery: a pilot study. Crit Care2013; 17: R138, https://link.springer.com/article/10.1186/cc12817 (2013).
5.
SchneiderAGGoodwinMDSchellemanA, et al.Contrast-enhanced ultrasonography to evaluate changes in renal cortical microcirculation induced by noradrenaline: a pilot study. Crit Care2014; 18: 653, https://link.springer.com/article/10.1186/s13054-014-0653-3 (2014).
Pérez LópezSOtero HernándezJVázquez MorenoN, et al.Brain death effects on catecholamine levels and subsequent cardiac damage assessed in organ donors. J Heart Lung Transplant2009; 28: 815–820, https://www.sciencedirect.com/science/article/pii/S1053249809002435 (2009).
ShivalkarBvan LoonJWielandW, et al.Variable effects of explosive or gradual increase of intracranial pressure on myocardial structure and function. Circulation1993; 87: 230–239.
11.
DietrichCAverkiouMCorreasJM, et al.An EFSUMB introduction into dynamic contrast-enhanced ultrasound (DCE-US) for quantification of tumour perfusion. Ultraschall in der Medizin - Eur J Ultrasound2012; 33: 344–351.
12.
van WylenDGD'AlecyLG. Regional blood flow distribution during the Cushing response: alterations with adrenergic blockade. Am J Physiol1985; 248: H98–108.
DamianakiAHendriks-BalkMBritoW, et al.Contrast-enhanced ultrasonography reveals a lower cortical perfusion and a decreased renal flow reserve in hypertensive patients. Nephrol Dial Transplant2024; 39: 242–250.
15.
Hendriks-BalkMCDamianakiAPolychronopoulouE, et al.Contrast-Enhanced ultrasonography enables the detection of a cold pressor test-induced increase in renal microcirculation in healthy participants. Front Cardiovasc Med2022; 9: 899327.
16.
HamillRWWoolfPDMcDonaldJV, et al.Catecholamines predict outcome in traumatic brain injury. Ann Neurol1987; 21: 438–443.
PennefatherSHBullockREMantleD, et al.Use of low dose arginine vasopressin to support brain-dead organ donors. Transplantation1995; 59: 58.
21.
PluradDSBrickerSNevilleA, et al.Arginine vasopressin significantly increases the rate of successful organ procurement in potential donors. Am J Surg2012; 204: 856–860; discussion 860-1, https://www.americanjournalofsurgery.com/article/S0002-9610(12)00433-3/fulltext (2012).
22.
BragadottirGRedforsBRickstenS-E. Mannitol increases renal blood flow and maintains filtration fraction and oxygenation in postoperative acute kidney injury: a prospective interventional study. Crit Care2012; 16: R159.
