title: Postoperative arterial blood gases in spay/castration dogs: a comparison of butorphanol versus hydromorphone.
authors.affiliation: University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: V L
authors.initials: VL
authors.lastname: Campbell
authors.affiliation: University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: K J
authors.initials: KJ
authors.lastname: Drobatz
authors.affiliation: University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: S Z
authors.initials: SZ
authors.lastname: Perkowski