Introduction: CBF tends to vary passively with changes of ABP during cerebral autorregulation (CA) impairment. This condition can lead to cerebral hyperemia or oliguemia and can be linked with brain edema and intracranial hypertension (ICH). The objective of this research is to analyze the CA during induced ICH and verify what is the effect of ICH treatment over CA.
Methods: Two-month old piglets were anesthetized with Propofol. Two 3-mm roles were performed located 1 cm lateral to the metopic suture: multiparameter catheter cerebral tissue (Neurovent-PTiO®; Raumedic) and pediatric bladder catheter, which was inflated with 0.9% saline solution; 4 ml and 7 ml triggered low intracranial pressure (ICP) and intracranial hypertension (ICH) respectively. After 1.5h, 3% saline solution was infused in the venous catheter. After 30 min the balloon was deflated. Low ICP was considered = 25 mmHg and ICH > 25 mmHg. The cerebral static autoregulation index (sARI) was evaluated through blood flow velocities (VM) obtained by ultrasound Doppler before and after each experimental step. Statistic: A two-way repeated-measures ANOVA was performed to determine the intervention’s effect on variables between the two groups.
Results: A total of 16 piglets underwent all data collection. The ICP variations were significant only in the ICH group (p=0.007). Although, ICP increase lead to an impairment of sCAI in both groups (table 2 and figure 2), it only reached statistical significance in the ICH group (p=0.001). There was increase in sCAI level after the saline injection (p-0.02) and after surgery (p=0.04) in the ICH group. There was an inverse correlation between ICP and sCAI (r = -0.68 and p<0.05) and direct correlation between cerebral pressure perfusion (CPP) with sCAI (r = 0.74 and p<0.05).
Conclusions: ICH impairs CA, which can recover normal levels after interventions to reduce the ICP.
Patient Care: The improved knowledge of the effects of treatment of intracranial hypertension on cerebral autoregulation may allow for changes in the intracranial hypertension management as well as interpretation of neuromonitoring information in neurocritical patients
Learning Objectives: To discuss about effects of intracranial hypertension on cerebral autoregulation
To analyze effect of hypertonic saline solution on cerebral autoregulation
To discuss the impact of low and severe intracranial hypertension in change in cerebral blood flow using ultrasound Doppler
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