Sleep alters respiratory mechanics and gas exchange, which can adversely affect arterial oxygenation. Whether sleep affects oxygenation in
hepatopulmonary syndrome is unknown. The aim of this study was to assess
oxygen desaturation during sleep in
hepatopulmonary syndrome. Twenty adults with
cirrhosis including 10 controls and 10 patients with
hepatopulmonary syndrome underwent home pulse-oximetry during sleep. Subjects at high risk for
obstructive sleep apnea were excluded through the Berlin questionnaire. Subjects who spent more than 10% of total sleep time with arterial oxygen saturation < 90% were classified as sleep-time
oxygen desaturators. Sleep-time desaturation was correlated with clinical variables. The results showed that 7 of 10
hepatopulmonary syndrome subjects and none of the 10 controls had sleep-time
oxygen desaturation. The median percentage of total sleep time with arterial oxygen saturation < 90% was significantly higher in
hepatopulmonary syndrome subjects than in controls (medians 25% versus 0%, P = 0.005).
Hepatopulmonary syndrome subjects had significantly lower wake-time arterial oxygen saturation level (median, 97% versus 95%; P = 0.003) and mean sleep-time arterial oxygen saturation level (median, 96% versus 91%; P = 0.0008) than did the controls. Sleep-time desaturation directly correlated with alveolar-arterial
oxygen gradient (P = 0.0007) and inversely correlated with wake-time arterial
oxygen tension (P = 0.0007) and oxygen saturation (P < 0.0001).
CONCLUSION: