Effects of different inspired oxygen fractions on sildenafil-induced pulmonary anti-hypertensive effects in a sheep model of acute pulmonary embolism
Abstract
Aims: Sildenafil is a pulmonary anti-hypertensive agent whose action could be modified by different fractions of inspired oxygen (FiO(2)). We compared the effects of pure oxygen (FiO(2) > 90%) or room air (21% FiO(2)) on the cardiopulmonary actions of sildenafil in sheep with acute pulmonary embolism (APE).Main methods: Forty anesthetized, mechanically ventilated sheep (34.9 +/- 5.4 kg), were randomly distributed into four groups (n = 4 per group): FiO(2) > 90% without intervention; APE induced by microspheres with FiO(2) > 90%, followed 30 min later by placebo (Emb(90)); or APE followed 30 min later by intravenous sildenafil (0.7 mg/kg over 30 min) with FiO(2) > 90% (Emb + Sild(90)) or 21% FiO(2) (Emb + Sild(21)). Variables were recorded until 30 min after the end of treatment administration.Key findings: Microsphere injection increased (P < 0.05) mean pulmonary artery pressure (MPAP) in all embolized groups (111-140% higher than that of baseline). Compared with values recorded 30 min after induction of APE (E-30), sildenafil induced greater decreases in MPAP in the Emb + Sil(90) group than in the Emb + Sil(21) group (23% and 14% lower than E-30, respectively). Hypotension (mean arterial pressure <60 mm Hg) Hg) was precipitated by sildenafil due to systemic vasodilation in the Emb + Sil(21) group. Embolization lowered the PaO2/FiO(2) ratio and increased venous admixture, but sildenafil did not alter the oxygenation impairment induced by APE.Significance: Sildenafil induces a more consistent pulmonary anti-hypertensive effect and causes less interference with the systemic circulation with the concomitant use of pure oxygen than that with room air in the APE setting. (C) 2015 Elsevier Inc. All rights reserved.
How to cite this document
Language
Sponsor
Grant number

Related items
Showing items related by title, author, creator and subject.
-
Núcleos de Ensino da Unesp: artigos 2009
Pinho, Sheila Zambello de; Oliveira, José Brás Barreto de
; Gazola, Rodrigo José Cristiano
; Mazotti, Adriano César
; Molero, Camila Schimite
; Mendes, Carolina Borghi
; Mello, Denise Fernandes de
; Marques, Emilia de Mendonça Rosa
; Talamoni, Jandira Liria Biscalquini
; Silva, José Humberto Dias da
et al. (Coleção PROGRAD (UNESP), 2011) [Livro]
-
Núcleos de Ensino da Unesp: artigos 2008
Pinho, Sheila Zambello de; Oliveira, José Brás Barreto de
; Pontes, Sueli Rodrigues
; Almeida, Djanira Soares de Oliveira e
; Godoy, Kathya Maria Ayres de
; Rosa, Claudia de Souza
; Nunes, Julianus Araújo
; Salvador, Sérgio Azevedo
; David, Célia Maria
; Vilche Peña, Angel Fidel
et al. (Coleção PROGRAD (UNESP), 2011) [Livro]
-
Ser e tornar-se professor: práticas educativas no contexto escolar
Pinho, Sheila Zambello de; Spazziani, Maria de Lourdes
; Mendonça, Sueli Guadelupe de Lima
; Rubo, Elisabete Aparecida Andrello
; Villarreal, Dalva Maria de Oliveira
; Duarte, Camila
; Okamoto, Mary Yoko
; Souza, Thais R.
; Garms, Gilza Maria Zauhy
; Marin, Fátima Aparecida Dias Gomes
et al. (Coleção PROGRAD (UNESP), 2012) [Livro]