Objective—To compare the time to desaturation in healthy dogs that breathed oxygen or room air for 3 minutes before induction of anesthesia.
Animals—20 healthy dogs.
Procedures—Dogs were sedated with morphine and acepromazine maleate. Dogs received a 3-minute treatment of room air or oxygen (100 mL/kg/min) via face mask. Arterial blood samples were collected before and after treatment to determine PaCO2, PaO2, pH, and SaO2; propofol (6 mg/kg, IV) was injected during a 7-second period, and the dogs were intubated. A lingual pulse oximeter probe was placed. Dogs remained disconnected from the breathing circuit until SpO2 equaled 90% (desaturation point) and then connected and ventilated until the SpO2 was ≥ 97%. Arterial blood samples were collected and SpO2 was recorded every 30 seconds for 4 minutes and then every minute until the desaturation point. Times to first breath and the desaturation point were recorded. Data were collected at 0, 5, 30, 60, 90, 120, and 150 seconds.
Results—Mean ± SEM time to desaturation differed significantly between dogs treated with room air (69.6 ± 10.6 seconds) and oxygen (297.8 ± 42.0 seconds). Lowest mean PaO2 and SaO2 when dogs were breathing room air were 62 ± 6.3 mm Hg and 82.3 ± 4%, respectively, at 30 seconds.
Conclusions and Clinical Relevance—Preoxygenation for 3 minutes increased the time to desaturation in healthy dogs sedated with acepromazine and morphine in which anesthesia was induced with propofol.
Objective—To compare preoperative administration
of meloxicam and butorphanol to perioperative administration
of butorphanol alone for control of postoperative
signs of pain in dogs.
Animals—40 client-owned dogs scheduled for surgical
repair of a cranial cruciate ligament rupture.
Procedure—Group-1 dogs received butorphanol (0.2
mg/kg, IV) and meloxicam (0.2 mg/kg, IV) just prior to
surgery. Group-2 dogs received butorphanol just prior
to surgery (0.2 mg/kg, IV) and at incision closure (0.1
mg/kg, IV). Pain assessment began 1 to 2 hours
before surgery and from extubation until 24 hours
after surgery by obtaining the following measurements:
the visual analog scale (VAS) score, cumulative
pain score (CPS), adjusted cumulative pain score,
modified cumulative pain score, and the adjusted
modified cumulative pain score (AMCPS). Serum cortisol
concentration was measured between 12 to 24
and between 1 to 2 hours prior to surgery, and at 30
minutes, and 1, 2, 4, 8, 18, and 24 hours after extubation.
Results—No significant differences between treatment
groups were observed in CPS or VAS score. At
8, 9, 10, and 11 hours after extubation, meloxicambutorphanol-
treated dogs had a significantly lower
AMCPS, compared with butorphanol-alone-treated
dogs. Total serum cortisol concentration (area under
the curve) during the measurement period was significantly
lower in meloxicam-butorphanol-treated
dogs, compared with butorphanol-alone treated dogs.
Conclusions and Clinical Relevance—Preoperative
single dose administration of meloxicam-butorphanol
is equivalent to or slightly better than the administration
of 2 perioperative doses of butorphanol for the
control of postoperative signs of pain in dogs. (Am J
Vet Res 2002;63:1557–1563)