ABSTRACTCardiovascular and respiratory function was studied after epidural injection of lignocaine hydrochloride (3 mg kg1) at the lumbosacral space in dogs premedicated with methadone (0–8 mg kg1), acepromazine (0.3 mg kg1) and atropine (0.6 to 1.2 mg). Analgesia was produced caudal to the third to fifth thoracic dermatomes; there was no significant change in cardiovascular function, respiratory rate, arterial blood pH or blood gas tensions. Relaxation of the hind leg and abdominal muscles was profound and haemorrhage caused a rapid fall in arterial blood pressure accompanied by tachycardi