Objectives To analyze the influences of mild and severe intracranial hypertension
on cerebral autoregulation (CA). Patients and Methods Duroc piglets were monitored
with an intracranial pressure (ICP) catheter. Intracranial hypertension was induced
via infusion of 4 or 7 ml of saline solution by a bladder catheter that was inserted
into the parietal lobe. The static cerebral autoregulation (sCA) index was evaluated
via cerebral blood flow velocities (CBFv). Piglets with ICPs <= 25 and > 25 mmHg were
considered as group 1 and 2, respectively. Continuous variables were evaluated using
the Kolmogorov-Smirnov goodness-of-fit test. The main parameters were collected before
and after ICH induction and compared using two-factor mixed-design ANOVAs with the
factor of experimental group (mild and severe ICH). Results In group 1 (ICP <= 25
mmHg), there were significant differences in sCA (p= .01) and ICP (p= .0002) between
the basal and balloon inflation conditions. In group 2 (ICP > 25 mmHg), there were
significant differences in CBFv (p= .0072), the sCA index (p= .0001) and ICP (p= .00001)
between the basal and balloon inflation conditions. Conclusion We conclude that ICH
may have a direct effect on mild and severe sCA.
