Pressure Reactivity Index (PRx): A Concept to Optimize Cerebral Perfusion Pressure in Traumatic Brain Injury

Akhyar Nur Uhud, Dewi Yulianti Bisri, Zafrullah Khany Jasa, Tatang Bisri

Abstract


Two common factors contributing to poorer outcomes in TBI patients are high intracranial pressure (ICP) and low cerebral perfusion pressure (CPP). These two factors constitute a vicious circle that will have a negative impact on TBI patients. An increase in ICP will cause a decrease in CPP, while a reduction in CPP will cause ischemia, which will worsen the high ICP. However, increasing the CPP by increasing MAP will not help the situation; in fact, it may worsen the impact due to impairment of cerebral autoregulation (CA). Therefore, it is critical to manage TBI patients with an ideal CPP. Pressure reactivity index (PRx) is a measurement of the linear relationship between the mean arterial pressure (MAP) and ICP. A positive correlation between ICP and MAP indicates an impairment of CA, which suggests a suboptimal CPP value. The basis of PRx theory is that the rise, because of the presence of CA, an increase in MAP should not be followed by the rise in ICP because there is a compensatory effect in the form of a decrease in cerebral blood volume, so that ICP does not increase. That being said, this mechanism will not work when the limit of autoregulation is exceeded. Based on PRx and CPP, an optimal CPP could be obtained by using a U-shaped curve. The outcomes of TBI patients can be enhanced by treating them according to their optimal CPP (CPPopt).


Keywords


Cerebral perfusion pressure, intracranial pressure, mean arterial pressure, pressure reactivity index, traumatic brain injury

Full Text:

PDF

References


Czosnyka M, Dias C. Role of pressure reactivity index in neurocritical care. In: Uchino H, Ushijima K, Ikeda Y, eds. Neuroanesthesia and cerebrospinal protection. Springer Japan. 2015, 223–36.

Saleh SC, Rehatta NM. Neuroanestesia dan Critical Care. 1st ed. Vol. 1. Surabaya: Airlangga University Press; 2023. 1–263.

Ragland J, Lee K. Critical care management and monitoring of intracranial pressure. J Neurocrit Care. 2016;9(2):105–12. Doi: https://doi.org/10.18700/jnc.160101

Canac N, Jalaleddini K, Thorpe SG, Thibeault CM, Hamilton RB. Review: Pathophysiology of intracranial hypertension and noninvasive intracranial pressure monitoring. Fluids Barriers CNS. 2020;17(1): 1–21. Doi: 10.1186/s12987-020-00201-8.

Hawryluk GWJ, Aguilera S, Buki A, Bulger E, Citerio G, Cooper DJ, et al. A management algorithm for patients with intracranial pressure monitoring: the Seattle International Severe Traumatic Brain Injury Consensus Conference (SIBICC). Intensiv Care Med. 2019; 45(12):1783-94. Doi: 10.1007/s00134-019-05805-9

Carney N, Totten AM, Ullman JS, Hawryluk GWJ, Bell MJ, Bratton SL, et al. Guidelines for the management of severe traumatic brain injury 4th Edition. Neurosurgery. 2016;0(0):1–15. Doi: 10.1227/NEU.0000000000001432

Tas J, Beqiri E, Van Kaam RC, Czosnyka M, Donnelly J, Haeren RH, et al. Targeting autoregulation-guided cerebral perfusion pressure after traumatic brain injury (COGiTATE): A feasibility randomized controlled clinical trial. J Neurotrauma. 2021;38(20):2790–800. Doi: 10.1089/neu.2021.0197

Czosnyka M, Czosnyka Z, Smielewski P. Pressure reactivity index: journey through the past 20 years. Acta Neurochir. 2017; 159(11): 2063–65. Doi: 10.1007/s00701-017-3310-1

Svedung Wettervik T, Howells T, Hillered L, Rostami E, Lewén A, Enblad P. Autoregulatory or fixed cerebral perfusion pressure targets in traumatic brain injury: Determining which is better in an energy metabolic perspective. J Neurotrauma. 2021;38(14):1969–78. Doi: 10.1089/neu.2020.7290

Prabhakar H, Sandhu K, Bhagat H, Durga P, Chawla R. Current concepts of optimal cerebral perfusion pressure in traumatic brain injury. J Anaesthesiol Clin Pharmacol. 2014;30(3):318-27. Doi: 10.4103/0970-9185.137260.

Patel S, Maria-Rios J, Parikh A, Okorie ON. Diagnosis and management of elevated intracranial pressure in the emergency department. Int J Emerg Med. 2023;16(1): 72.

Tsigaras ZA, Weeden M, McNamara R, Jeffcote T, Udy AA, Anstey J, et al. The pressure reactivity index as a measure of cerebral autoregulation and its application in traumatic brain injury management. Crit Care Resusc. 2023;25(4): 229–36. Doi: 10.1016/j.ccrj.2023.10.009.

Cottrell JE, Patel PM. Neuroanesthesia. 7th ed. Soriano SG, Patel PM, Cottrell JE, Flexman AM, editors. Philadelphia: Elsevier Inc; 2024.

Prabhakar H. Textbook of neuroanesthesia and neurocritical care. Prabhakar H, Ali Z, editors. Singapore: Springer Singapore; 2019.

Budohoski KP, Czosnyka M, De Riva N, Smielewski P, Pickard JD, Menon DK, et al. The relationship between cerebral blood flow autoregulation and cerebrovascular pressure reactivity after traumatic brain injury. Neurosurgery. 2012;71(3):652–60. discussion 660-1. doi: 10.1227/NEU.0b013e318260feb1

Gritti P, Bonfanti M, Zangari R, Bonanomi E, Farina A, Pezzetti G, et al. Cerebral autoregulation in traumatic brain injury: ultra-low-frequency pressure reactivity index and intracranial pressure across age groups. Crit Care. 2024 ;28(1): 1-13. Doi: 10.1186/s13054-024-04814-5

Aries MJH, Czosnyka M, Budohoski KP, Steiner LA, Lavinio A, Kolias AG, et al. Continuous determination of optimal cerebral perfusion pressure in traumatic brain injury. Crit Care Med. 2012;40(8):2456–63. Doi; 10.1097/CCM.0b013e3182514eb6.

Zweifel C, Lavinio A, Steiner LA, Radolovich D, Smielewski P, Timofeev I, et al. Continuous monitoring of cerebrovascular pressure reactivity in patients with head injury. Neurosurg Focus. 2008;25(4): E2. Doi: 10.3171/FOC.2008.25.10.E2

Donnelly J, Czosnyka M, Adams H, Robba C, Steiner LA, Cardim D, et al. Pressure reactivity-based optimal cerebral perfusion pressure in a traumatic brain injury cohort Acta Neurochir Suppl. 2018;126:209–12. Doi: 10.1007/978-3-319-65798-1_43.

Petkus V, Preiksaitis A, Krakauskaite S, Zubaviciute E, Rocka S, Rastenyte D, et al. Benefit on optimal cerebral perfusion pressure targeted treatment for traumatic brain injury patients. J Crit Care. 2017;41:49–55. Doi: 10.1016/j.jcrc.2017.04.029




DOI: https://doi.org/10.24244/jni.v14i2.693

Refbacks

  • There are currently no refbacks.


                                    

 

JNI is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License