fluids should be administered if cardiovascular compromise is evident, but they may exacerbate pulmonary or cerebral edema. The volume of blood loss may be significant in hypocoagulable patients or small‐sized patients [1, 2]. Treatment includes replacement of the injection port and administration of intravenous fluids or whole blood, if signs of hypovolemia are present or severe [1].
Expected outcome
If recognized promptly and vascular air aspiration is limited, clinical signs can improve and horses can return to normal after vascular air emboli. In one study, 19% of horses were euthanized or died subsequent to vascular air embolism [27–31]. Similarly, blood loss from a disconnected catheter was unlikely to be significant or affect prognosis, unless the hemorrhage was not recognized or treated.
References
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3 3. Spriet, M., Trela, J.M., and Galuppo, L.D. (2015). Ultrasound‐guided injection of the median artery in the standing sedated horse. Equine Vet. J. 47: 245–248.
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8 8. Lorello, O. and Orsini, J.A. (2014). Intravenous catheter placement. In: Equine Emergencies: Procedures and Treatments, 4e (ed. J.A. Orsini and T.J. Divers), 9–11. St. Louis: Elsevier Saunders.
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12 12. Spurlock, S.L., Spurlock, G.H., Parker, G. et al. (1990). Long‐term jugular vein catheterization in horses. J. Am. Vet. Med. Assoc. 196: 425–430.
13 13. Ettlinger, J.J., Palmer, J.E., and Benson, C. (1992). Bacteria found on intravenous catheters removed from horses. Vet. Rec. 130: 248–249.
14 14. Fiege, K., Schwarzwald, C.C., and Bombeli, T. (2003). Comparison of unfractioned and low molecular weight heparin for prophylaxis of coagulopathies in 52 horses with colic: a randomized double‐blind clinical trial. Equine Vet. J. 35: 506–513.
15 15. Geraghty, T.E., Love, S., Taylor, D.J. et al. (2009). Assessment of subclinical venous catheter‐related diseases in horses and associated risk factors. Vet. Rec. 164: 227–231.
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18 18. Lankveld, D.P.K., Ensink, J.M., Dijk, P.V. et al. (2001). Factors influencing the occurrence of thrombophlebitis after post‐surgical long‐term intravenous catheterization of colic horses: a study of 38 cases. J. Vet. Med. A. 48: 545–552.
19 19. Rikjenhuizen, A.B. and van Swieten, H.A. (1998). Reconstruction of the jugular vein in horses with post thrombophlebitis stenosis using saphenous vein graft. Equine Vet. J. 30: 236–239.
20 20. Culp, W.T.N., Weisse, C., Berent, A.C. et al. (2008). Percutaneous endovascular retrieval of an intravascular foreign body in five dogs, a goat, and a horse. J. Am. Vet. Med. Assoc. 232: 1850–1856.
21 21. Pokharel, K., Biswas, B.K., Tripathi, M. et al. (2015). Missed central venous guide wires: a systematic analysis of published case reports. Crit. Care Med. 42: 1745–1756.
22 22. Nannarone, S., Falchero, V., Gialletti, R. et al. (2013). Successful removal of a guidewire from the jugular vein of a mature horse. Equine Vet. Educ. 25: 173–176.
23 23. Hoskinson, J.J., Wooten, P., and Evans, R. (1991). Nonsurgical removal of a catheter embolus from the heart of a foal. J. Am. Vet. Med. Assoc. 199: 233–235.
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4 Complications of Endoscopy
Julie E. Dechant DVM, MS, DACVS, DACVECC
School of Veterinary Medicine, University of California–Davis, Davis, California
Overview
Endoscopy is performed using a flexible video‐endoscope, although rigid endoscopes may be used for certain surgical applications. The
