Cerebral vascular resistance assessed by transcranial color Doppler ultrasonography in patients with chronic liver diseases

Abstract

Background and Aim: Cerebral hemodynamic derangement is well known in patients with liver cirrhosis. The advent of transcranial Doppler enables a non‐invasive observation of cerebral hemodynamics. To evaluate the clinical usefulness we examined cross‐sectionally and longitudinally cerebral hemodynamic parameters in patients with cirrhosis. Methods: The subjects of the cross‐sectional study were 117 patients with cirrhosis, 15 patients with chronic hepatitis and 25 healthy controls. The longitudinal study included 26 cirrhotic patients without encephalopathy, and 27 cirrhotic patients with encephalopathy. The pulsatility and resistive indices of the right middle cerebral artery were used as parameters of cerebral hemodynamics. Results: Cerebral pulsatility and resistive indices were significantly higher in patients with cirrhosis (1.05 ± 0.23, P < 0.0001 and 0.63 ± 0.07, P < 0.0001, respectively) than in the controls (0.75 ± 0.11 and 0.55 ± 0.05, respectively) and patients with chronic hepatitis (0.81 ± 0.11 and 0.52 ± 0.05, respectively). Cerebral pulsatility and resistive indices were significantly related with the severity of liver cirrhosis. Patients with encephalopathy had higher cerebral pulsatility and resistive indices than patients without encephalopathy. In the longitudinal studies, cerebral pulsatility and resistive indices were changed in parallel with the severity of cirrhosis and encephalopathy. Cerebral pulsatility and resistive indices were significantly correlated with the blood ammonia level and serum levels of bilirubin and albumin. Conclusion: These cross‐sectional and longitudinal studies showed that cerebral vascular resistance indices measured by using transcranial Doppler were increased in association with the severity of cirrhosis and encephalopathy. Cerebral pulsatility and resistive indices are real‐time and useful parameters to assess and monitor cirrhotic patients.

Cerebral Hemodynamics and Cognitive Function in Cirrhotic Patients with Hepatic Encephalopathy

“…Simultaneously, PI and RI paralleled the severity of HE. As PI reflects the compliance and elasticity of the cerebral vasculature and RI reflects diastolic, systolic, and resistant status of the cerebral vasculature this result suggests that systolic and diastolic cerebral autoregulation is impaired, as PI and RI increased in cirrhotic patients with HE and cerebral hemodynamics was related to severity of HE, consistent with results from previous studies [33, 34]. …”

Cerebral hemodynamics in patients with cirrhosis

“…Kawakami et al (17) showed that increased cerebral vascular resistance, which may change with the severity of hepatic encephalopathy, is directly related to hepatic encephalopathy. They compared 27 patients with hepatic encephalopathy to 26 patients without hepatic encephalopathy and found that the PI and RI levels were higher in patients with hepatic encephalopathy.…”

Transcranial doppler assessment of cerebral perfusion in critically ill septic patients: a pilot study

“…In vitro and in vivo studies show that both indexes are related to changes in peripheral vascular resistances [23-25]. Increased PI is associated with angiographically demonstrated diffuse intracranial vessel disease [26], and both RI and PI have been found to be increased in patients who suffer from diabetes with microangiopathy or advanced cirrhosis with encephalopathy [27,28]. The increased values of PI and RI that we observed in septic patients (compared with control critically ill patients) should be interpreted as a manifestation of enhanced vascular resistance in the cerebral circulation during early sepsis.…”