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Patients with cirrhosis have a hyperdynamic circulation and an abnormal blood volume distribution with central hypovolemia, an activated sympathetic nervous s ystem (SNS) as well as the renin-angiotensin-aldosterone system (RAAS). As the hyperdynamic circulation in cirrhosis may be present only in the supine patient , we studied the humoral and central hemodynamic responses to changes with postu re. Twenty-three patients with alcoholic cirrhosis (Child-Turcotte-Pugh class es A/B/C: 2/13/8) and 14 healthy controls were entered. Measurements of central hemodynamics and activation of SNS and RAAS were taken in the supine position, a fter 30°head-down tilting, and after 60°passive head-up tilting for a maximu m of 20 minutes. After the head-up tilting, the central blood volume (CBV) decr eased in both groups, but the decrease was significantly smaller in patients tha n in controls (-19%vs. -36%, P < .01). Central circulation time increased on ly in the patients (+30%vs. -1%, P < .01). The absolute increases in circula ting norepinephrine and renin after head-up tilting were significantly higher i n the patients than in the controls (P < .05 and P < .01, respectively). In pati ents with cirrhosis, changes in SNS and RAAS were related to changes in arterial blood pressure, systemic vascular resistance, heart rate, non-CBV, plasma volu me, and arterial compliance. In conclusion, cardiovascular and humoral responses to changes in posture are clearly abnormal in patients with cirrhosis. Head-up tilting decreases the CBV less in patients with cirrhosis, and the results sugg est a differential regulation of central hemodynamics in patients with cirrhosis .
Patients with cirrhosis have a hyperdynamic circulation and an abnormal blood volume distribution with central hypovolemia, an activated sympathetic nervous system (SNS) as well as the renin-angiotensin-aldosterone system (RAAS). As the hyperdynamic circulation in cirrhosis may be present only in the supine patient, we studied the humoral and central hemodynamic responses to changes with postu re. Twenty-three patients with alcoholic cirrhosis (Child-Turcotte-Pugh class es A / B / C: 2/13/8) and 14 healthy controls were entered. Measurements of central hemodynamics and activation of SNS and RAAS were taken in the supine position, a fter 30 ° head-down tilting, and after 60 ° passive head-up tilting for a maximu m of 20 minutes. After the head- up tilting, the central blood volume (CBV) decr eased in both groups, but the decrease was significantly smaller in patients tha n in controls (-19% vs. -36%, P <.01) in the patients (+ 30% vs. -1%, P <.01). Th e absolute increases in circula ting norepinephrine and renin after head-up tilting were significantly higher in the patients than in the controls (P <.05 and P <.01, respectively). In pati ents with cirrhosis, changes in SNS and RAAS were related to changes in arterial blood pressure, systemic vascular resistance, heart rate, non-CBV, plasma volu me, and arterial compliance. In conclusion, cardiovascular and humoral responses to changes in posture are clearly abnormal in patients with cirrhosis. Head-up tilting decreases the CBV less in patients with cirrhosis, and the results sugg est a differential regulation of central hemodynamics in patients with cirrhosis.