• anesthesia complications;
  • ASA PS;
  • canine;
  • lung disease


Objective: To define the peri-anesthetic risk factors that are associated with the development of postoperative pulmonary complications (PPCs) in dogs following laparotomy.

Study design: Retrospective study.

Animals: One hundred and sixty-two dogs that underwent laparotomy at a veterinary teaching hospital.

Methods: Cases were evaluated for factors including signalment, American Society of Anesthesiologists (ASA) physical status (PS) score, duration of fast, duration of anesthesia, anesthetic and analgesic protocols, fluid and blood product therapy, animal positioning, and postoperative temperature.

Results: Statistically significant differences between dogs that developed PPCs and those that did not (nPPCs) were identified in the following categories: ASA PS score≥III (P=0.041), emergent surgery (P=0.038), longer duration of anesthesia (P=0.0462), and use of butorphanol or oxymorphone instead of hydromorphone for postoperative medication (P=0.04 and 0.015, respectively). Dogs that received transfusions of stored blood products (fresh frozen plasma or packed red blood cells) during their hospital stay were also more likely to develop PPCs (P=0.035 and 0.005, respectively). Dogs that developed PPCs were also more likely to have received antagonists for potent opiates or benzodiazepines postoperatively and to have recovered in the intensive care unit (ICU) (P=0.03 and 0.009, respectively).

Conclusions: Dogs with ASA PS scores≥III, or those requiring longer or emergency anesthesia are at a higher risk of developing PPCs. Additionally, dogs receiving stored blood products in the perioperative period may be at risk for pulmonary complications. Dogs fitting criteria for the above risk factors should be monitored closely postoperatively for development of pulmonary complications.