Jennifer C. Hess1, DVM; Kurt A. Grimm2, DVM, MS, PhD, DACVA, DACVP; G. John Benson2, DVM, MS, DACVA; William A. Tranquilli2, DVM, MS, DACVA; Ragenia Sarr2, CVT; Peter D. Constable2, BVSc, MS, PhD, DACVIM
Vascular access ports (VAP) have been used for arterial blood collection in non-lacertilians. We describe a technique for VAP placement in seven 1 kg adult green iguanas and report the arterial blood gas values from five iguanas. The blood samples were obtained using the ports while the animals were manually restrained.
VAPs were purchased from Access Technologies in Skokie, IL, USA and consisted of a Sla port with a Hydrocoat catheter (size 3.5 French). Using sterile technique, a 1.5-cm incision was made on the right-lateral neck. Blunt dissection ventral to the external jugular vein exposed the internal and external carotid arteries. The catheter was inserted into the right internal carotid artery and then guided to the common carotid artery. The other end of the catheter was connected to a port located caudal-dorsal to the ipsilateral scapula. The skin was closed, and the port was flushed twice a week with 0.2 ml heparinized 0.9% saline. Postoperative difficulties with the VAP included port disconnection (n=1), inability to aspirate blood after a few weeks (n=2), and infection (n=1).
The iguanas were breathing room air prior to and during blood collection at an ambient temperature of 32°C. From the five healthy iguanas with a functional VAP, the blood pH, PCO2, PO2, HCO3-, BE, Na+, K+, Cl-, Ca++, Anion Gap, PCV, and TP (37°C) were 7.45±0.07; 36.5±6.5 mm Hg, 93.5±5.5 mm Hg, 24.4±2.2 mmol/L, 0.2±2.2 mmol/L, 158.6±3.6 mmol/L, 3.0±0.5 mmol/L, 133±5 mmol/L, 5.4±0.4 mmol/L, 4.6±1.3 mEq/L, 28.8±5.7%, 4.8±1.3 g/dl respectively (mean ± SD). Except for the low anion gap, these values are similar to the normal values for mammals. In conclusion, VAPs can be used to collect arterial blood in conscious green iguanas.
Reprinted with permission: American College of Veterinary Anesthesiologists 29th Annual Meeting, Phoenix, AZ, 19–25 October 2004. Veterinary Anaesthesia and Analgesia. 32(4):236–248.