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Caudal epidural anesthesia is an easy and inexpensive method of analgesia that is commonly used in cattle. A high caudal epidural at the sacrococcygeal space (S5–Co1) desensitizes sacral nerves S2, S3, S4, and S5. The low caudal epidural at first coccygeal space (Co1–Co2) desensitizes sacral nerves S3, S4, and S5; as the anesthetic dose increases, nerves cranial to S2 may also become affected [6]. If possible, the hair should be clipped and the skin scrubbed and disinfected.

Standing alongside the cow, the tail should be moved up and down to locate the fossa between the last sacral vertebra and the first coccygeal vertebra (first freely moveable space) or between the first and second coccygeal vertebrae. An 18‐gauge, 3.8‐cm needle (with no syringe attached) is directed perpendicular to the skin surface. Once the skin is penetrated, place a drop of local anesthetic solution in the hub of the needle (hanging drop technique). The needle should then be advanced slowly until the anesthetic solution is drawn into the epidural space by negative pressure. The syringe may then be attached to the needle and anesthetic solution slowly injected with no resistance (Figure 17.4a). The dose of local anesthetic to be used is 0.5 ml per 45 kg body weight.

Figure 17.4 (a) Needle placement for caudal epidural. Source: Image courtesy of Dr. Douglas Hostetler.

Adapted with permission from Lumb and Jones’ Veterinary Anesthesia.

(b) Catheter placement for continuous flow epidural.

Source: From [1], © 2007, John Wiley & Sons. Adapted with permission from Lumb and Jones’ Veterinary Anesthesia.

An increased dose of local anesthetic can be used to facilitate other urogenital procedures including teaser bull preparation and ventral midline cesarean section. This is referred to as high‐volume caudal epidural anesthesia and is performed in the same way as the standard caudal epidural, only increasing the volume of local anesthetic used. The recommended dose is 1 ml per 5 kg body weight; however, volumes up to 0.5 ml/kg have been used without adverse effects. The patient will lose control of the hindlimbs, so recumbency is a must when using this technique. The effects on the hindlimbs may last up to four to six hours after administration. It is recommended that hobbles be placed on the hindlimbs and the patient be recovered in an area with good footing and left alone until they are able to stand unassisted [4, 7].