Short Communication Long-term facial artery catheter implantation for serial arterial blood sampling and invasive arterial blood pressure measurement in horses Deborah Penteado Martins Dias ⇑ , Luisa Gouvêa Teixeira, Paulo Aléscio Canola, Raquel Mincarelli Albernaz, José Antônio Marques, José Corrêa de Lacerda Neto Departamento de Clínica e Cirurgia Veterinária, Faculdade de Ciências Agrárias e Veterinárias – FCAV/Unesp, Jaboticabal – SP 14884-900, Brazil article info Article history: Accepted 17 June 2011 Keywords: Arterial blood pressure Arterial blood sampling Catheter Exercise Horse abstract The purpose of this investigation was to evaluate surgical catheter implantation in the facial artery of horses and the long-term maintenance of such arteries using heparin and ascorbic acid as filling solution. Nine horses were implanted with a polyurethane catheter. The catheters were flushed with a heparin/ ascorbic acid solution every 8 h and remained patent for 25 days. Arterial blood samples were collected twice a day, and one exercise test that included serial blood samples and arterial pressure recordings was performed on a treadmill. Polyurethane catheters surgically implanted in the facial artery can be kept patent by filling with a heparin/ascorbic acid solution and provide convenient invasive arterial access in horses which is suitable for use for serial blood sampling and blood pressure recordings, even during exercise on treadmill. Ó 2011 Elsevier Ltd. All rights reserved. Invasive arterial access is important for obtaining substantial data in a large range of research protocols. However, serial arterial sampling and dynamic cardiac variable measurement are difficult due to complications associated with catheter implantation and maintenance. Subcutaneous relocation of the common carotid ar- tery is a technique commonly used for accessing arterial blood in horses (Butler, 1962; Tavernor, 1969; Dueck et al., 1982; Orsini and Roby, 1997; Prassinos et al., 2001) and can be used to record arterial blood pressure at rest (Tavernor, 1969). Other authors have used the medial coccygeal artery to measure arterial pressure at rest (Parry et al., 1984; Magdesian, 2004; Piccione et al., 2009), while the use of wireless telemetry has also been described (Ricco et al., 2009). Using catheterization of relocated common carotid arteries, Tavernor (1969) performed pressure recordings in conscious horses, and Evans and Rose (1988) performed arterial blood sam- pling of Thoroughbreds during exercise on a treadmill. Magdesian (2004) reported the feasibility of transverse facial artery catheter- ization for monitoring arterial pressure. Unfortunately, none of these studies described their methods for flushing the catheters, and they did not indicate the length of time over which catheter function was maintained. The period over which an implanted percutaneous catheter can be used is limited by difficulties in avoiding intra-catheter throm- bus formation in studies longer than 12 h and by proper catheter placement, especially for exercise evaluations on a treadmill. Addi- tionally, methods of catheterization which require measurements to be taken over long periods of time, such as for indirect and tele- metric blood pressure evaluation, have never been tested in exer- cising horses. The purpose of this investigation was to evaluate the feasibility of surgical catheter implantation in the facial artery, the long-term maintenance of catheters using heparin and ascorbic acid as a fill- ing solution, and the feasibility of using such catheters for serial blood sampling and blood pressure evaluation at rest and during exercise on a treadmill. The study received ethical approval (CEBEA – Protocol number 004302-06). Nine adult mixed breed healthy horses, five males and four females, with a mean age of 9 ± 2 years and a mean body mass of 297 ± 8 kg were used. One week before surgery, the horses were accustomed to the treadmill (Galloper, Sahinco) for 3 days, so that they could walk, trot and canter without difficulty. Food, but not water, was withheld for 12 h before the surgical procedure. Procaine penicillin G (Pencivet Plus, Intervet) at 22,000 U/kg IM was given preoperatively. The horses were re- strained in stocks, sedated with 0.1 mg/kg IM acepromazine (Acep- ran, Univet) and pethidine chloride (Petinan, BioChimico) at 2.0 mg/kg IM, followed by infiltration of 5 mL of 2% lidocaine chlo- ride (Xylestesin, Cristália) into the subcutaneous tissue over the fa- cial artery. After sterile preparation, a 4 cm skin incision was made in a caudoventral direction starting from 3 cm above the ventral aspect of the horizontal mandibular branch. The incision was deepened by 1090-0233/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.tvjl.2011.06.031 ⇑ Corresponding author. Tel.: +55 16 32092631. E-mail address: deborah_dias@hotmail.com (D.P.M. Dias). The Veterinary Journal 192 (2012) 541–543 Contents lists available at ScienceDirect The Veterinary Journal journal homepage: www.elsevier.com/locate/tvjl