Emprego da pletismografia para mensuração indireta da pressão arterial sistólica em gatas anestesiadas para ovariosalpingohisterectomia

Abstract

The measurement of blood pressure in small animals is of utmost importance for the diagnosis and staging of several chronic diseases, such as cardiovascular disorders, renal and endocrine diseases. In anesthesiology is a vital parameter in the monitoring of anesthetized patients, along with other measures it can indicate the depth of anesthesia, pain perception or vasodilation induced by drugs. The measurement methods are divided into direct and indirect methods, being the direct method the gold standard for this measure, but requires some degree of technical skill. The indirect methods, for its time, offer greater convenience for use on a day to day basis. This study aimed to evaluate the reliability of the use of the pleth as an indicator of systolic blood pressure in feline anesthetized and submitted to ovariohysterectomy elective. Participated in the survey 14 mongrel cats, aged between one and five years, previously set to reduce the influence of stress on the results obtained, on the day of the surgical procedure were pre-medicated with meperidine 4 mg/kg intramuscular, induced to anesthesia with propofol 4 mg/kg intravenously and maintained in surgical anesthesia with isoflurane diluted in 100% oxygen using a universal vaporizer. Measurements occurred simultaneously with the vascular Doppler was used appropriate cuff size for each patient which was placed above the radiocarpal joint of the left forelimb, the doppler sensor was placed on the ulnar artery and the pulse oximeter sensor was placed between the digits in the same state. The cuff was inflated up to suppress the arterial pulse and the pleth, then was deflated gradually until the pulse returned to be audible and which formed the wave on the display of the pulse oximeter. The two values were documented, as well as other vital parameters and subsequently submitted to one-way analysis of variance, followed by post-hoc Neuman Keuls test, in addition to simple correlation test to check the influence of a parameter on the other (Doppler X Pulse Oximeter). The study demonstrated that the pleth generated by pulse oximetry, as compared to the Doppler method, proved to be efficient as indirect method for measuring blood pressure in anaesthetised cats, becoming a cheaper alternative and also practical for routine use in veterinary medicine.