Skin perfusion decreases after dexmedetomidine administration in dogs but remains stable for up to 60 minutes under general anesthesia.

OBJECTIVE

To determine the effect of general anesthesia on skin perfusion in healthy dogs.

METHODS

Client-owned dogs (n = 22) undergoing a dental cleaning procedure were enrolled in a prospective study. All dogs were administered trazodone (4 to 6 mg/kg, PO) the evening prior to and morning of their dental procedure. After premedication (0.2 mg/kg of butorphanol and 4 μg/kg of dexmedetomidine, IM), anesthesia was induced with propofol (4 mg/kg, IV, to effect) and maintained with isoflurane in 100% oxygen. The mean speckle contrast (MSC; inversely proportional to perfusion) was recorded using laser speckle contrast imaging for the pinna, hind limb, neck, and ventral midline prior to any medication, after premedication, and every 15 minutes while under isoflurane anesthesia for 60 minutes. The percentage of change in MSC from baseline was recorded.

RESULTS

MSC increased after premedication versus prior to any medication for all sites, indicating a decrease in perfusion. The magnitude was greater for the ventral midline (37.2 ± 8.1%), neck (28.3 ± 9.5%), and pinna (26.8 ± 6.1%) compared to the hind limb (8.7 ± 3.1%). A mild decrease in MSC (increased perfusion) was observed over time during isoflurane anesthesia. The magnitude was greater for the pinna (-11.0 ± 3.5%) compared to the neck (-1.8 ± 1.6%), midline (8.1 ± 0.2%), and hind limb (3.5 ± 0.6%).

CONCLUSIONS

A decrease in skin perfusion following IM dexmedetomidine was seen. No further decrease in skin perfusion was seen over time for up to 60 minutes under isoflurane anesthesia.

CLINICAL RELEVANCE

Veterinarians should not hesitate to place patients under general anesthesia for short durations even when skin perfusion is a concern; however, it may be prudent to avoid dexmedetomidine.