Related Experiment Video
Updated: Oct 26, 2026
Non-Intubated Video-Assisted Thoracoscopic Surgery
Published on: May 26, 2023
Transthoracic lung ultrasound for perioperative assessment of dogs undergoing nonemergency anesthesia: a prospective
Emily P Wheeler1, Bonnie L Hay Kraus1, Jonathan P Mochel2
1Iowa State University College of Veterinary Medicine, Veterinary Clinical Sciences, Lloyd Veterinary Medical Center, Ames, IA, USA.
Objective:
To explore whether lung ultrasound (LUS) findings suggestive of atelectasis in humans could be identified in dogs after anesthesia and to evaluate whether these findings were associated with clinical variables.
Study Design:
Prospective, repeated-measures observational study with masked offline analysis.
Animals:
Forty-four client-owned dogs (American Society of Anesthesiologists physical status classification I-II) undergoing nonemergency surgical procedures in dorsal recumbency; 27 breathed spontaneously throughout anesthesia and 17 had intermittent positive-pressure ventilation.
Methods:
Dogs underwent a standardized LUS examination at two time points: immediately pre- (time point 1) and postanesthesia (time point 2). LUS examinations were performed by a single observer trained in a standardized protocol with dogs standing or in sternal recumbency. A curvilinear 8-5 MHz transducer probe was used to capture 4-second cineloops at eight sites (right and left caudal, perihilar, middle, and cranial). Images were assessed by an observer masked to dog and time point using a standardized scoring system (maximum score of 32) developed for the study that considered B-lines (vertical hyperechoic artefacts), irregular pleural line, and subpleural abnormalities. At time point 2, while dogs were receiving an FiO2 of 100%, arterial partial pressure of oxygen was measured using a point-of-care blood gas analyzer on samples collected from the dorsal pedal artery. LUS scores were compared between time points using the Wilcoxon signed-rank test. Animal, anesthetic, surgical, and respiratory variables were assessed for association with time point 2 LUS scores using univariable linear models adjusted for the time point 1 LUS score.
Results:
LUS scores increased significantly (p < 0.001) from time point 1 to 2: median (range) 1 (0-5) versus 7 (0-18); Hodges-Lehmann median increase 6.5 points (95% confidence interval 5.0 to 8.5), p < 0.001. Exploratory analyses did not detect an association between time point 2 LUS scores and any assessed variables after correction for multiple comparisons (age, adjusted p = 0.443).
Conclusions:
LUS scores increased in dogs following general anesthesia.
Clinical Relevance:
Further investigation of LUS as an accessible and affordable diagnostic method for detecting atelectasis in the perianesthetic period is warranted.
