Administering anesthesia to small animals is a routine aspect of veterinary practice. However, amidst the intricacies of anesthesia management, veterinary professionals are confronted with several challenges–most notably, peri-anesthetic hypothermia. This condition, characterized by a significant drop in body temperature, presents a multitude of implications for patient safety and recovery.
A prevalent concern for veterinarians and pet owners, ensuring preventive measures are in place is of vital importance. The consequences of peri-anesthetic hypothermia are vast, impacting physiological functions such as heart rate, drug metabolism, and respiratory patterns. Furthermore, the risk of mortality during the recovery phase of anesthesia underscores the urgency to mitigate the negative effects of sedation in small animals.
This article explores the causes, implications, and available solutions through comprehensive management strategies aimed at ensuring positive patient outcomes. From pre-warming techniques to using specialized warming devices, recent insights and advancements in animal anesthesia can provide veterinary professionals with the knowledge and tools to navigate the complexities of hypothermia prevention and treatment.
Peri-anesthetic hypothermia—a cause for concern
Peri-anesthetic hypothermia, when body temperature drops below 95 F, occurs in up to 80 percent of anesthetized cats and dogs.1Several factors contribute to this occurrence, including their smaller body size, altered peripheral perfusion from premedication and anesthetic drugs, intubation whereby inhaled gas bypasses the nose, breathing cold gases, and heat loss from the skin surface or open body cavities.
Heat loss is exponential. Premedication causes mild hypothermia, with dogs and cats typically experiencing a temperature decrease of up to one to two degrees F over the 30 to 60 minutes before anesthesia induction. This initial drop in core body temperature precedes the precipitous, critical heat loss of one to five degrees that occurs within the first 15 to 30 minutes after induction, during clip and prep time. However, once animals are draped for surgery, heat loss slows down considerably.1 (Figure 1)
