The problem with audible alarms in general is that at times of high stress, people may not 'hear' them. A search for 'inattentional deafness' will bring up some good papers on the topic. If designing an alerting system, 'cognitive tunnelling' should also be considered. There are many academic papers on both topics, and they have been examined in aviation, clinical, and other contexts.
In aviation, we are fortunate that most of our audible alerts have been standardised; one sound means the same thing across all manufacturers. In the ward and theatre, this standardisation has not taken place, and clinicians have to cope with different machines which use the same sound for completely different, sometimes opposite, alert conditions. I'm not sure if that's true in the veterinary world.
Generally, I agree with vapilot; a well-trained, experienced, and alert, nurse, with the back-up of appropriate audible and visual alerts, would be my preference.