Study on the correlation of the changes of cerebral hemodynamics with intracranial pressure and cerebral perfusion pressure in patients with moderate and severe craniocerebral trauma
HUANG Guo-dong, LI Wei-ping, FU You-zeng, WANG Jian-zhong, WU Jian-ming, GAO Yong-zhong. Department of Neurosurgery, Second People's Hospital of Shenzhen City, Shenzhen 518035, China
Objective To explore the relationship of the changes of cerebral hemodynamics with intracranial pressure (ICP) and cerebral perfusion pressure (CPP) in patients with moderate and severe head injuries. Methods A prospective study of 52 patients with moderate and severe head injuries was done in their hemodynamics parameters of bilateral middle cerebral arteries monitored by transcranial Doppler (TCD), including peak systolic velocity (Vp), diastolic velocity(Vd), Mean velocity (Vm), pulsatility index(PI)and resistent index(RI). All patients were also detected in ICP, CPP, and mean arterial blood pressure (MABP). The correlation of the hemodynamics parameters and MABP, ICP CPP (CPP=MABP-ICP)was analyzed. Results There were positive correlations between PI, RI and ICP (PI: r=0.881, P0.0001; RI: r=0.789, P0.0001), inverse correlations between PI, RI and CPP (PI: r=-0.559, P0.01; RI: r=-0.508, P0.01), high positive correlations between non-invasive CPP (nCPP), non-invasive ICP (nICP) and invasive gold standard (CPP, ICP) (nCPP: r=0.815, P0.0001; nICP: r=0.831, P0.0001). By multivariant stepwise regression analysis, ICP, CPP and PI, RI, Vd, Vm were indicated the most close correlation; the regression equations between ICP and PI, RI: ICP=-8.593+24.295PI (t=13.216, P0.0001), ICP=-47.948+109.208RI (t=9.098, P0.0001); the equations between CPP and PI, MABP: CPP = 15.596-22.8-86PI + 0.910 MABP (F=76.597, P0.0001). Conclusion The non-invasive cerebral hemodynamics may actually and timely reflect the changes of ICP and CPP in patients with moderate and severe head injuries, so this is an effective means for monitoring ICP and CPP with advantages of non-invasiveness, safety, less cost and convenience.