title: Reflection of differential pulmonary perfusion in polytrauma patients on differential lung ventilation (DLV). A comparison of two CO2-derived methods.
abstract: Seventeen polytrauma patients with asymmetric pulmonary contusion were treated with differential lung ventilation (DLV). The ratios of differential values of end-tidal CO2 concentration (ETCO2) and CO2 excretion ml/min (VCO2) were compared as indirect parameters for differential pulmonary perfusion. Both CO2-derived methods indicated asymmetry after starting DLV suggesting asymmetric pulmonary perfusion as a consequence of contusion. Prior to stopping DLV a significant improvement in asymmetry was indicated by the differential ratios of ETCO2 and VCO2 values. The ETCO2 ratio increased from 0.74 +/- 0.17 to 0.88 +/- 0.10, the VCO2 ratio from 0.57 +/- 0.23 to 0.86 +/- 0.11. In two patients with very severe contusion who underwent bilobectomies a marked difference between the ratios of ETCO2 and VCO2 was observed. It is concluded that differential measurement of CO2-derived variables may be useful in indicating differential perfusion in clinical practice on DLV. In very severe asymmetric contusion ETCO2 ratios may underestimate the differential perfusion ratio.
authors.affiliation: Afdeling voor Anaesthesiologie en Intensive Care, Academisch Ziekenhuis Groningen, The Netherlands.
authors.forename: D F
authors.initials: DF
authors.lastname: Zandstra
authors.forename: C P
authors.initials: CP
authors.lastname: Stoutenbeek
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002245:Carbon Dioxide / Q000032:analysis; D006801:Humans; D008168:Lung / Q000503:physiopathology / Q000601:surgery; D055370:Lung Injury; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009104:Multiple Trauma / Q000503:physiopathology / Q000601:surgery / Q000628:therapy*; D011013:Pneumonectomy; D012121:Respiration, Artificial; D014692:Ventilation-Perfusion Ratio
chemical_list: D002245:Carbon Dioxide