title: [Right-to-left shunt determination in dog lungs under inhalation anesthesia with rebreathing and non-rebreathing system].
abstract: OBJECTIVE
  To investigatge right-to-left shunt determination in dog lungs under inhalantion anesthesia with non-rebreathing and rebreathing systems and fraction of inspired oxygen (F I O2) of 0.9 and 0.4, respectively.
  
  
  METHODS
  Two groups of 10 dogs each under inhalation anesthesia with sevoflurane: GI in which it was utilized non-rebreathing semiclosed system and F I O2 = 0.9, and GII in which it was utilized rebreathing semiclosed system and F I O2 = 0.4. The study parameters were: heart rate, medium arterial pressure, right-to-left intrapulmonary shunt, hematocrit, hemoglobin, arterial partial pressure of oxygen, mixed venous partial pressure of oxygen, mixed venous oxygen saturation, arterial partial pressure of carbon dioxide, partial pressure of water in the alveoli.
  
  
  RESULTS
  Shunt results were significantly different between the two groups - GI data were higher than GII in all the evaluated moments. Hence, the group with nonrebreathing (GI) developed a superior grade of intrapulmonary shunt when compared with the rebreathing group (GII). The partial pressure of water in the alveoli was significantly higher in GII.
  
  
  CONCLUSIONS
  The inhalation anesthesia with non-rebreathing system and F I O2 = 0.9 developed a higher grade of intrapulmonary right-to-left shunt when compared with the rebreathing system and F I O2 = 0.4. The higher humidity in GII contributed to the result.
authors.affiliation: School of Veterinary Medicine, São Paulo Methodistic University, São Bernardo do Campo, Brazil.
authors.forename: André Leguthe
authors.initials: AL
authors.lastname: Rosa
authors.forename: Patrícia Cristina Azevedo
authors.initials: PC
authors.lastname: Mota
authors.forename: Yara Marcondes Machado
authors.initials: YM
authors.lastname: Castiglia
mesh_terms: D000764:Anesthesia, Closed-Circuit; D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D000818:Animals; D004285:Dogs; D005260:Female; D006813:Humidity; D006993:Hypnotics and Sedatives / Q000008:administration & dosage*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage; D023421:Models, Animal; D010100:Oxygen / Q000008:administration & dosage*; D010101:Oxygen Consumption / Q000502:physiology; D011652:Pulmonary Circulation / Q000502:physiology*; D012121:Respiration, Artificial; D000077149:Sevoflurane; D013874:Thiopental / Q000008:administration & dosage
chemical_list: D018685:Anesthetics, Inhalation; D006993:Hypnotics and Sedatives; D008738:Methyl Ethers; D000077149:Sevoflurane; D013874:Thiopental; D010100:Oxygen