Have You Heard Of Propofol?
Propofol is one of the most widely used anesthetic agents worldwide, in the medical and veterinary fields. Up until a few years ago, however, it wasn’t exactly a household name. Now it’s a drug name that most people recognize, sadly as a result of the tragedy surrounding the death of Michael Jackson.
As a veterinarian myself, I have had first-hand experience using propofol when anesthetizing my patients in general practice. As with all general anesthetic agents, it is a very useful and versatile drug, and when administered by trained medical personnel (I’m talking about anesthesiologists, nurse anesthetists, and veterinarians here), it can be used safely. As is also the case with all anesthetic drugs, however, it is not without risks.
How Does Propofol Work?
It’s a very rapid and short-acting hypnotic agent (causing almost instantaneous sleep). Although its mechanism of action isn’t completely understood, one of its proposed actions is to potentiate GABAA receptors in the brain. GABA is an inhibitory neurotransmitter that is essential for proper brain functioning – it binds to its receptors in the central nervous
system and reduces excessive brain activity, promoting a state of calm.
What Are The Risks?
Propofol not only reduces a patient’s blood pressure, but it also depresses their respiration. In this short video, CNN’s Dr Sanjay Gupta watches an anesthesiologist colleague at work in the operating room. You can see for yourself how the patient stops breathing when given propofol anesthesia.
The respiratory depression is a known, and expected effect of the agent. This is the reason why patients receiving propofol anesthesia are mechanically ventilated, as is the case in a hospital operating room. Let’s not forget that an important aspect of anesthesia involves not just putting patients to sleep, but recovering them and waking them from the procedure.
So you can understand how it can be a deadly agent when used by untrained personnel, or if used inappropriately and without the necessary ancillary equipment. If propofol is used without a patient being adequately monitored by trained medical professionals, and without intubation, the effects can be fatal.
If an intubated patient suffers from respiratory distress during anesthesia, the stage is already set for medical staff to be able to respond rapidly and mechanically ventilate him, hopefully to resuscitation. Without intubation and monitoring, however, a patient in respiratory distress can progress to respiratory failure and death very quickly due to the rapid action of the drug. Additionally, when combined with other drugs that also cause respiratory depression, such as the benzodiazepines (the class of drugs that Valium belongs to), these adverse effects are exacerbated.
Milk Of Amnesia
Its milky white color has led to propofol being jokingly referred to by medical professionals as the “milk of amnesia”. But on the contrary, medical professionals using the drug typically respect its potency and take their role as a patient protector very seriously. This is not a drug to be dispensed for at-home use, and neither is it considered a sleep aid.
Image credit Wikipedia