I will only move forward with your permission when ready. At this stage your pet will be sleeping deeply and very comfortably under a surgical level of anaesthesia.
For dogs, I will place a small intravenous catheter in to a vein in their back leg. I can administer a dose of barbiturate through this line. This will deepen your friend’s plane of anaesthesia still further and allow them to pass. If your pet’s health is such that it is not possible to place a catheter I can instead move, under anaesthesia, to administer the barbiturate without the need for intravenous access.
For cats, I can give the barbiturate either in to a vein in their leg or in to their tummy, easing them deeper in to anaesthesia, and they will pass.