Effects of endoscopic variceal sclerotherapy on azygos vein blood flow and systemic haemodynamics

Relationships between splenorenal shunt/portal vein diameter ratio and systemic hemodynamics in patients with liver cirrhosis

OBJECTIVES

The purpose of this study was to investigate the relationships between the splenorenal shunt (SRS)/portal vein (PV) diameter ratio (SRS/PV ratio) and systemic hemodynamics in patients with liver cirrhosis.

PATIENTS AND METHODS

Thirty-seven patients with SRS due to liver cirrhosis were included in this study. SRS was evaluated in the retropancreatic space on contrast-enhanced CT and the diameter was measured at the maximum point. Systemic hemodynamics was studied using a thermodilution catheter.

RESULTS

The SRS/PV ratio showed a significant correlation with the cardiac index (p < 0.01), and showed an inverse correlation with the systemic vascular resistance index and the arteriovenous oxygen content difference [C(a-v)O2] (p < 0.01). The Child-Pugh score showed a correlation with the SRS/PV ratio (p < 0.01). The SRS/PV ratio was 0.89 ± 0.52, 1.02 ± 0.51, and 1.74 ± 0.50 in the Child-Pugh A, B, and C classes, respectively. The SRS/PV ratio in the Child-Pugh C class was significantly higher than those in classes A and B (p < 0.01). The plasma ammonia level was 75.3 ± 23.2 in the group with an SRS/PV ratio <1.0 (n = 19) versus 102.6 ± 34.8 in the group with an SRS/PV ratio ≥1.0 (n = 18), and the ratio of encephalopathy was 5% (1/19) in the group with an SRS/PV ratio <1.0 (n = 19) versus 50% (9/18) in the group with an SRS/PV ratio ≥1.0 (n = 18), respectively. The differences between the two groups were statistically significant (p < 0.01).

CONCLUSIONS

We conclude that the increase in the SRS/PV ratio is accompanied by deteriorated liver function, hyperdynamic status, and narrowed C(a-v)O2.

Effects of endoscopic variceal ligation on oxygen transport and the arterial lactate levels in patients with cirrhosis

OBJECTIVE

Despite the increased cardiac output and oxygen delivery, an impaired oxygen uptake has been noted in patients with cirrhosis. We recently observed that endoscopic variceal ligation decreased the cardiac output due to a reduction in the cardiac preload. It is thus possible that a variceal ligation decreases the oxygen delivery and thereby negatively influences tissue oxygenation in patients receiving such treatment. We thus investigated the effects of variceal ligation on oxygen delivery, oxygen uptake, and the arterial lactate levels.

METHODS

There were 22 patients with compensated cirrhosis and risky esophageal varices (Child's class A:B=13:9). Twelve patients underwent an endoscopic variceal ligation and 10 patients received gastroscopy as a control. The cardiac function, blood gas status, oxygen delivery, and arterial lactate concentration were also assessed before and after variceal ligation. The oxygen uptake was calculated by the Fick equation.

RESULTS

Following variceal ligation, there was an immediate decrease in the cardiac output and oxygen delivery. The reduction in oxygen delivery was associated with a slight but significant increase in the arterial lactate concentration. The decreased oxygen delivery was also associated with a concomitant decrease in the oxygen uptake. In the control subjects, gastroscopy did not alter the systemic hemodynamics, arterial oxygen status, or arterial lactate levels.

CONCLUSION

We found a significant decrease in the oxygen delivery in patients undergoing an endoscopic variceal ligation. Such deteriorated tissue oxygenation may be serious especially in patients with a low oxygen transport ability such as in patients with variceal hemorrhage with anemia. However, the clinical significance of these changes remains unclear and further studies are therefore warranted.