SN4 SHORT NOTE 5M

Describe Propofol Infusion Syndrome in detail.

General Surgery · Final Professional

Definition

Propofol infusion syndrome (PRIS) is a rare but potentially fatal complication of prolonged, high-dose propofol infusion — classically in critically ill patients and children sedated in intensive care for long periods. It is thought to result from impaired mitochondrial fatty-acid metabolism.

Features & Management

It is characterised by severe metabolic (lactic) acidosis, rhabdomyolysis, hyperkalaemia, acute kidney injury, lipaemia, and cardiac failure/arrhythmias that can be refractory and fatal. Management is to stop propofol immediately, switch to an alternative sedative, and provide supportive care (correct acidosis, cardiovascular and renal support, sometimes haemofiltration). Prevention is by avoiding prolonged high-dose infusion and monitoring for early acidosis.

DANGER / REMEMBER

Suspect PRIS in any patient on a prolonged high-dose propofol infusion who develops an unexplained metabolic acidosis, rising lactate or arrhythmia — stop the propofol at once. It is largely a syndrome of ICU sedation, not of short operative infusions.

Recognition in the ICU

The importance of propofol infusion syndrome lies in recognising it early, because once established it is often refractory and fatal: the warning signs are an unexplained and worsening metabolic acidosis with a rising lactate, new arrhythmias or a widening QRS, and evidence of rhabdomyolysis in a patient who has been receiving propofol at high dose for more than a day or two. The response is to stop propofol immediately and switch to an alternative sedative, alongside aggressive supportive care, which is why sedation guidelines cap the dose and duration of propofol infusions and encourage vigilance for early acidosis.

CLINICAL PEARL

Suspect propofol infusion syndrome whenever a patient on a prolonged, high-dose propofol infusion develops an unexplained metabolic acidosis and rising lactate; the treatment is simple in principle — stop the propofol at once and support the patient — but the syndrome is often fatal once established, so prevention and early recognition are everything.

CLINICAL PEARL

In short, a rising lactate on long-term propofol is propofol infusion syndrome until proven otherwise.

Limit dose and duration in intensive care sedation.

KEY POINT

Key points TO remember

PRIS: rare, fatal complication of prolonged high-dose propofol infusion (ICU, children).
Impaired mitochondrial fatty-acid metabolism.
Features: metabolic acidosis, rhabdomyolysis, hyperkalaemia, AKI, cardiac failure/arrhythmia.
Stop propofol immediately + supportive care; prevent by avoiding prolonged high-dose infusion.

EXAM TIP

Sources: Morgan & Mikhail’s Clinical Anesthesiology; Miller’s Anesthesia; Ajay Yadav’s Short Textbook of Anaesthesia.

All questions in Intravenous Anaesthetic Agents

Every General Surgery chapter →