title: Hepatopulmonary syndrome: a prospective study of relationships between severity of liver disease, PaO(2) response to 100% oxygen, and brain uptake after (99m)Tc MAA lung scanning.
abstract: BACKGROUND
  Because of the spectrum of intrapulmonary vascular dilation that characterizes hepatopulmonary syndrome (HPS), PaO(2) while breathing 100% oxygen varies. Abnormal extrapulmonary uptake of (99m)Tc macroaggregated albumin (MAA) after lung perfusion is common.
  
  
  OBJECTIVE
  To describe relationships between (1) severity of liver disease measured by the Child-Pugh (CP) classification; (2) PaO(2) while breathing room air (RA) and 100% oxygen on 100% oxygen; and (3) extrapulmonary (brain) uptake of (99m)Tc MAA after lung scanning.
  
  
  METHODS
  We prospectively measured PaO(2) on RA, PaO(2) on 100% oxygen, and brain uptake after lung perfusion of (99m)Tc MAA in 25 consecutive HPS patients.
  
  
  RESULTS
  Mean PaO(2) on RA, PaO(2) on 100% oxygen, PaCO(2) on RA, and (99m)Tc MAA brain uptake were similar when categorized by CP classification. Brain uptake was abnormal (> or = 6%) in 24 patients (96%). Brain uptake was 29 +/- 20% (mean +/- SD) and correlated inversely with PaO(2) on RA (r = -0.57; p<0.05) and PaO(2) on 100% oxygen (r = -0.41; p<0.05). Seven patients (28%) had additional nonvascular pulmonary abnormalities and lower PaO(2) on 100% oxygen (215+/-133 mm Hg vs 391+/-137 mm Hg; p<0.007). Eight patients (32%) died. Mortality in patients without coexistent pulmonary abnormalities was associated with greater brain uptake of (99m)Tc MAA (48+/-18% vs 25+/-20%; p<0.04) and lower PaO(2) on RA (40+/-7 mm Hg vs 57+/-11 mm Hg; p<0.001).
  
  
  CONCLUSIONS
  The degree of hypoxemia associated with HPS was not related to the CP severity of liver disease. HPS patients with additional nonvascular pulmonary abnormalities exhibited lower PaO(2) on 100% oxygen. Mortality was associated with lower PaO(2) on RA, and with greater brain uptake of (99m)Tc MAA.
authors.affiliation: Division of Pulmonary and Critical Care, Mayo Clinic, Rochester, MN, USA. krowka@mayo.edu
authors.forename: M J
authors.initials: MJ
authors.lastname: Krowka
authors.forename: G A
authors.initials: GA
authors.lastname: Wiseman
authors.forename: O L
authors.initials: OL
authors.lastname: Burnett
authors.forename: J R
authors.initials: JR
authors.lastname: Spivey
authors.forename: T
authors.initials: T
authors.lastname: Therneau
authors.forename: M K
authors.initials: MK
authors.lastname: Porayko
authors.forename: R H
authors.initials: RH
authors.lastname: Wiesner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000792:Angiography; D001921:Brain / Q000378:metabolism*; D002648:Child; D005260:Female; D020065:Hepatopulmonary Syndrome / Q000150:complications / Q000175:diagnosis* / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D000860:Hypoxia / Q000175:diagnosis / Q000209:etiology / Q000378:metabolism; D008168:Lung / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D012129:Respiratory Function Tests; D012720:Severity of Illness Index; D013438:Sulfhydryl Compounds / Q000493:pharmacokinetics; D013668:Technetium Tc 99m Aggregated Albumin / Q000493:pharmacokinetics
chemical_list: D013438:Sulfhydryl Compounds; D013668:Technetium Tc 99m Aggregated Albumin; C082426:technetium Tc99m-mercaptoacetyl albumin; D010100:Oxygen