Procedural sedation and anesthesia (PSA) is defined as the process of depressing a patient’s consciousness to perform minimally invasive or unpleasant procedures. This term is original from human medicine but can also be applied to veterinary sciences.
This clinical review focuses on cats, where PSA may be required for various procedures and the elected protocol is highly dependent on the individual. The decision between PSA or general anesthesia requires reflection; advantages and disadvantages of each technique should be cautiously assessed, and a rigorous initial assessment of the patient should be performed. The latter is crucial to the protocol choice therefore, cat-friendly handling together with the recommendation of oral sedatives (gabapentin or trazadone) prior to the veterinary visit, should be considered to alleviate stress and anxiety in some cats.
It is known that cats have an increased risk of anesthetic death than dogs and that Himalayans have a higher risk of complications due to their brachycephalic conformation. Other factors, like age, weight, the type of procedure and the anesthetic protocol also affect the rate of mortality and are detailed in the paper.
Before the PSA, risk factors should be identified, required material should be ready and emergency drugs dosage should be calculated. Neuroleptanalgesia (the combination of an opioid analgesic and a tranquilizer/sedative) is recommended during PSA, not only because of the improved consequent level of sedation and analgesia and the better quality of recovery, but also for its lower adverse cardiopulmonary effects when compared with either drug administered alone at similar doses. Nevertheless, there are some occasional cases where opioids alone or the combination benzodiazepine-opioid are indicated.
Many evidence-based feline PSA protocols are detailed throughout this review. For example, it is affirmed that dexmedetomidine combinations may affect interpretations in echocardiography results, that acepromazine is not recommended in patients with hypovolemia, dehydration, or high risk of bleeding and that propofol causes dose-dependent cardiorespiratory depression.
The authors emphasize the importance of monitoring the patient, for a minimum of three hours following the end of the procedure as most of the fatalities occur within this period. It is also important to bear in mind that factors like body temperature, pain, and duration of the procedure, influence the quality of recovery.
Simon, Bradley T. and Steagall, Paulo V. Feline procedural sedation and analgesia. Journal of Feline Medicine and Surgery (2020) 22, 1029–1045. DOI: 10.1177/1098612X20965830