title: Appropriate timing of blood sampling for blood gas analysis in the ventilated rabbit.
abstract: Arterial and venous blood gas analyses (BGAs) are essential to evaluate devices that measure biological oxygenation. The appropriate timing of blood sampling for BGA after respiratory rate (RR) change in animal experiments has not been reported. This study investigated the appropriate timing of blood sampling for BGA in ventilated rabbits and whether venous samples are an alternative to arterial samples.
  
  
  
  Under general anesthesia, 14 rabbits (body weight, 3.02 ± 0.09 kg) were ventilated and their RR was changed (40/min, 30/min, and 20/min). Blood was sampled through cervical arterial and venous catheters. Experiment 1: in seven rabbits, arterial BGA was measured at 0, 0.5, 1, 2, 3, 5, 10, 15, and 20 min after the RR change. Experiment 2: in seven different rabbits, simultaneous arterial and venous BGA were measured at 0, 2, 5, 10, 15, and 20 min after the RR change.
  
  
  
  Oxygen partial pressure (PO2) and saturation (SO2) of the arterial blood stabilized 0.5 min after the RR changed. In venous BGA, no index stabilized during observation. The arterial and venous values of the carbon dioxide partial pressure (PCO2) and pH had significant correlations (arterial PCO2= 0.9316 × venous PCO2-4.4425 [r = 0.9178]; arterial pH = 1.0835 × venous pH-0.5795 [r = 0.9453]).
  
  
  
  In ventilated rabbits, arterial PO2and SO2stabilized in 0.5 min. No venous value stabilized after the RR change. Only the PCO2and pH of venous samples may be an alternative to arterial samples under the defined formula.
authors.affiliation: Department of Obstetrics and Gynecology, National Defense Medical College, Tokorozawa, Saitama, Japan. Electronic address: sei@ndmc.ac.jp.
authors.forename: Kiguna
authors.initials: K
authors.lastname: Sei
authors.affiliation: Division of Environmental Medicine, National Defense Medical College Research Institute, Tokorozawa, Saitama, Japan. Electronic address: fujitama@ndmc.ac.jp.
authors.forename: Masanori
authors.initials: M
authors.lastname: Fujita
authors.affiliation: Department of Medical Engineering, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Shinpei
authors.initials: S
authors.lastname: Okawa
authors.affiliation: Department of Medical Engineering, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Hirasawa
authors.affiliation: Department of Medical Engineering, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kushibiki
authors.affiliation: Department of Obstetrics and Gynecology, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Sasa
authors.affiliation: Department of Obstetrics and Gynecology, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Furuya
authors.affiliation: Department of Medical Engineering, National Defense Medical College, Tokorozawa, Saitama, Japan.
authors.forename: Miya
authors.initials: M
authors.lastname: Ishihara
mesh_terms: D000768:Anesthesia, General; D000818:Animals; D001158:Arteries; D015415:Biomarkers / Q000097:blood; D001784:Blood Gas Analysis; D001800:Blood Specimen Collection / Q000379:methods*; D002245:Carbon Dioxide / Q000097:blood*; D005260:Female; D010100:Oxygen / Q000097:blood*; D011817:Rabbits; D012121:Respiration, Artificial; D056152:Respiratory Rate; D014680:Veins
chemical_list: D015415:Biomarkers; D002245:Carbon Dioxide; D010100:Oxygen
keywords: Arterial sample; Blood gas analysis; Oxygen saturation; Rabbit; Sample timing; Venous sample