Side effects
There is considerable variability in a patient's response to propofol, at times showing profound sedation with small doses.
One of propofol's most common side effects is pain on injection, especially in smaller veins, due to activation of the sensory nerve pain receptor, TRPA1,[55]. This can be mitigated by pretreatment with lidocaine[56] or slower infusion in a large vein (antecubital fossa).
Propofol may effect low blood pressure related to vasodilation. Reports of blood pressure drops of 30% or more are thought to be at least partially due to inhibition of sympathetic nerve activity.[57] This effect is related to the dose and rate of propofol administration. It may also be potentiated by opioid analgesics.[58]
Transient apnea and cerebrovascular effects have followed induction doses. Propofol has more pronounced hemodynamic effects relative to many intravenous anesthetic agents.[59] Propofol can also decrease systemic vascular resistance, myocardial blood flow, and oxygen consumption, possibly through direct vasodilation.[60] There are also reports that it may cause green discoloration of the urine.[61]
Although propofol is widely used in the adult ICU setting, the side effects associated with medication seem to be more concerning in children. In the 1990s, multiple reported deaths of children in ICUs associated with propofol sedation prompted the FDA to issue a warning.[62]
As a respiratory depressant, propofol frequently produces apnea. The persistence of apnea can depend on factors such as premedication, dose administered, and rate of administration, and may sometimes persist for longer than 60 seconds.[63] Possibly as the result of depression of the central inspiratory drive, propofol may produce significant decreases in respiratory rate, minute volume, tidal volume, mean inspiratory flow rate, and functional residual capacity.[59]
Propofol administration also results in decreased cerebral blood flow, cerebral metabolic oxygen consumption, and intracranial pressure.[64] In addition, propofol may decrease intraocular pressure by as much as 50% in patients with normal intraocular pressure.[65]
A more serious but rare side effect is dystonia.[66] Mild myoclonic movements are common, as with other intravenous hypnotic agents. Propofol appears to be safe for use in porphyria, and has not been known to trigger malignant hyperthermia.
Propofol is also reported to induce priapism in some individuals,[67][68] and has been observed to suppress REM sleep and to worsen the poor sleep quality in some patients.[69]
Rare side effects include:[70] As with any other general anesthetic agent, propofol should be administered only where appropriately trained staff and facilities for monitoring are available, as well as proper airway management, a supply of supplemental oxygen, artificial ventilation, and cardiovascular resuscitation.[71]
Because of propofol's formulation (using lecithin and soybean oil), it is prone to bacterial contamination, despite the presence of the bacterial inhibitor benzyl alcohol; consequently, some hospital facilities require the IV tubing (of continuous propofol infusions) to be changed after 12 hours. This is a preventive measure against microbial growth and potential infection.[72]
- anxiety
- changes in vision
- cloudy urine
- coughing up blood
- delirium or hallucinations
- difficult urination
- difficulty swallowing
- dry eyes, mouth, nose, or throat
Propofol infusion syndrome
A rare, but serious, side effect is propofol infusion syndrome. This potentially lethal metabolic derangement has been reported in critically ill patients after a prolonged infusion of high-dose propofol, sometimes in combination with catecholamines and/or corticosteroids.[73]
