Abstract

Objective-To evaluate the use of the oxygen content-based index, Fshunt, as an indicator of venous admixture ([Formula: see text]s/[Formula: see text]t) at various fractions of inspired oxygen (Fio(2)s) in anesthetized sheep undergoing Flung or 2-lung ventilation. Animals-6 healthy adult female sheep. Procedures-Sheep were anesthetized and administered 5 different Fio(2)s (0.21, 0.40, 0.60, 0.80, and 1.00) in random order during 2-lung mechanical ventilation. Arterial and mixed venous blood samples were obtained at each Fio(2) after a 15-minute stabilization period. Vital capacity alveolar recruitment maneuvers were performed after blood collection. The previously used Fio(2) sequence was reversed for sample collection during Flung ventilation. Blood samples were analyzed for arterial, pulmonary end-capillary, and mixed venous oxygen content and partial pressure and for hemoglobin concentration. Oxygen hemoglobin saturation, [Formula: see text]s/[Formula: see text]t, Fshunt, and oxygen tension-based indices (OTIs; including Pao(2):Fio(2), alveolar-arterial difference in partial pressure of oxygen [Pao(2) - Pao(2)], [Pao(2) - Pao(2)]:Fio(2), [Pao(2) - Pao(2)]:Pao(2), and Pao(2):Pao(2)) were calculated at each Fio(2); associations were evaluated with linear regression analysis, concordance, and correlation tests. Intermethod agreement between [Formula: see text]s/[Formula: see text]t and Fshunt was tested via Bland-Altman analysis. Results-Strong and significant associations and substantial agreement were detected between Fshunt and [Formula: see text]s/[Formula: see text]t. Relationships between OTIs and [Formula: see text]s/[Formula: see text]t varied, but overall correlations were weak. Conclusions and Clinical Relevance-Whereas OTIs were generally poor indicators of [Formula: see text]s/[Formula: see text]t, Fshunt was a good indicator of [Formula: see text]s/[Formula: see text]t at various Fio(2)s, regardless of the magnitude of [Formula: see text]s/[Formula: see text]t, and could be potentially used as a surrogate for [Formula: see text]s/[Formula: see text]t measurements in healthy sheep.

Autore Pugliese

• Grasso Salvatore

Tutti gli autori

• GRASSO S.

Titolo volume/Rivista

Non Disponibile

Anno di pubblicazione

2012

ISSN

0002-9645

ISBN

Non Disponibile

Numero di citazioni Wos

Nessuna citazione

Ultimo Aggiornamento Citazioni

Non Disponibile

Numero di citazioni Scopus

21

Ultimo Aggiornamento Citazioni

Non Disponibile

Settori ERC

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Codici ASJC

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