Evaluation of indirect blood pressure monitors in isoflurane anesthetized cats: optimization of Doppler accuracy and evaluation of the performance of a new oscillometric monitor

• Grant number: 12/09837-8
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2012
• End date: July 31, 2014
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Francisco José Teixeira Neto
• Grantee: Francisco José Teixeira Neto
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Rationale: Although the Doppler is the most commonly used blood pressure monitor cats, systolic blood pressures (SBP) derived from this monitor underestimate the SBP recorded via the invasive method by 25 mmHg in this animal species (Caulkett et al, 1998). It is possible to optimize the accuracy of Doppler estimates of SBP by comparing several cuff positionings and/or by using cuffs of smaller size than those traditionally used (cuff width-to-girth ratio < 40%). However, there are no studies evaluating these possibilities with the aim of optimizing the accuracy of SBP values obtained with the Doppler monitor in feline species. In addition to the Doppler monitor, the PetMap® is an oscillometric blood pressure monitor that has been frequently used in cats. However, the agreement between the blood pressures derived from this monitor and the blood pressures derived from the direct method has not been evaluated in cats presented with hypotension and hypertension.Objectives: Objective 1: To compare cuffs with 2 different sizes (# 1 and # 2) placed in different locations (above the tarsus, below the tarsus, distal third of the radius/ulna), aiming to find the Doppler monitor configuration that allows better agreement with SBP derived from the direct method in cats. Objective 2: To compare the agreement of blood pressures derived from a hand-held oscillometric monitor (PetMap®) and from a tabletop oscillometric monitor (Digicare®) with the blood pressures obtained from the direct method in cats. Animals: 8 adult catsProcedures: After premedication with midazolam (0.2 mg/kg), ketamine (5 mg/kg), and methadone (0.1 mg/kg), anesthesia will be induced with propofol and maintained with isoflurane in oxygen under mechanical ventilation. With the Doppler monitor, cuff sizes #1 and #2 will be placed above and below the tarsus, and above the carpus. The cuff for the PetMap® and the Digicare® monitors will be placed on the thoracic limb. Based on direct blood pressure measurements (catheterization of the dorsal pedal artery), conditions of low systolic blood pressure (SBP < 90 and e 60 mmHg), normal SBP ((e 90 and < 140 mmHg) and high SBP ((>140 and d 180) will be induced via changes in isoflurane concentrations and or administration of dopamine. Differences between non-invasive methods and the gold standard (direct blood pressure) will be analyzed by the Bland-Altman method. Means biases will be compared by ANOVA, followed by a Tukey's test (p<0.05). Expected results: Objective 1: It is anticipated that the agreement between SBP values derived from the Doppler monitor and from the invasive method will be optimized with the use of smaller cuff size (width-to-girth ratio < 0.3). We also expect to identify which cuff positioning (above the tarsus, below the tarsus, and above the carpus) would be recommended to optimize the agreement between direct and indirect (Doppler) blood pressure in cats. Objective 2: We expect to verify if the new oscillometric blood pressure monitor (PetMap®) presents an adequate performance (bias of < 10 mmHg in comparison with the gold standard method during most of the occasions) in order to be accepted as a clinically useful method of blood pressure monitoring in anaesthetized cats. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CEREJO, SOFIA A.; TEIXEIRA-NETO, FRANCISCO J.; GAROFALO, NATACHE A.; RODRIGUES, JESSICA C.; CELEITA-RODRIGUEZ, NATHALIA; LAGOS-CARVAJAL, ANGIE P.. Comparison of two species-specific oscillometric blood pressure monitors with direct blood pressure measurement in anesthetized cats. JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, v. 27, n. 4, p. 409-418, JUL-AUG 2017. (12/09837-8)

CEREJO, SOFIA A.; TEIXEIRA-NETO, FRANCISCO J.; GAROFALO, NATACHE A.; PIMENTA, EUTALIO L. M.; ZANUZZO, FELIPE S.; KLEIN, V, ADRIANA. Effects of cuff size and position on the agreement between arterial blood pressure measured by Doppler ultrasound and through a dorsal pedal artery catheter in anesthetized cats. VETERINARY ANAESTHESIA AND ANALGESIA, v. 47, n. 2, p. 191-199, MAR 2020. (12/09837-8)