Propofol was compared to benzodiazepines and opioids in clinical trials involving ICU patients. Of these, 302 received propofol and comprise the overall safety database for ICU sedation.
Across all clinical studies, the mean infusion maintenance rate for all propofol patients was 27 ± 21 mcg/kg/min. The maintenance infusion rates required to maintain adequate sedation ranged from 2.8 mcg/kg/min to 130 mcg/kg/min. The infusion rate was lower in patients over 55 years of age (approximately 20 mcg/kg/min) compared to patients under 55 years of age (approximately 38 mcg/kg/min). Although there are reports of reduced analgesic requirements, most patients received opioids for analgesia during maintenance of ICU sedation. In these studies, morphine or fentanyl was used as needed for analgesia. Some patients also received benzodiazepines and/or neuromuscular blocking agents. During long-term maintenance of sedation, some ICU patients were awakened once or twice every 24 hours for assessment of neurologic or respiratory function.
In Medical and Postsurgical ICU studies comparing propofol to benzodiazepine infusion or bolus, there were no apparent differences in maintenance of adequate sedation, mean arterial pressure, or laboratory findings. Like the comparators, propofol reduced blood cortisol during sedation while maintaining responsivity to challenges with adrenocorticotropic hormone (ACTH). Case reports from the published literature generally reflect that propofol has been used safely in patients with a history of porphyria or malignant hyperthermia.
In hemodynamically stable head trauma patients ranging in age from 19 years to 43 years, adequate sedation was maintained with propofol or morphine. There were no apparent differences in adequacy of sedation, intracranial pressure, cerebral perfusion pressure, or neurologic recovery between the treatment groups. In literature reports of severely head-injured patients in Neurosurgical ICUs, propofol infusion and hyperventilation, both with and without diuretics, controlled intracranial pressure while maintaining cerebral perfusion pressure. In some patients, bolus doses resulted in decreased blood pressure and compromised cerebral perfusion pressure.
Propofol was found to be effective in status epilepticus which was refractory to the standard anticonvulsant therapies. For these patients, as well as for ARDS/respiratory failure and tetanus patients, sedation maintenance dosages were generally higher than those for other critically ill patient populations.
(See WARNINGS and DOSAGE AND ADMINISTRATION - Handling Procedures.) The administration of propofol should be initiated as a continuous infusion and changes in the rate of administration made slowly (greater than 5 min) in order to minimize hypotension and avoid acute overdosage. (See DOSAGE AND ADMINISTRATION.)
Patients should be monitored for early signs of significant hypotension and/or cardiovascular depression, which may be profound. These effects are responsive to discontinuation of propofol, IV fluid administration, and/or vasopressor therapy. In the elderly, debilitated, or ASA-PS III or IV patients, rapid (single or repeated) bolus administration should not be used during sedation in order to minimize undesirable cardiorespiratory depression, including hypotension, apnea, airway obstruction, and oxygen desaturation.
As with other sedative medications, there is wide interpatient variability in propofol dosage requirements, and these requirements may change with time.
Failure to reduce the infusion rate in patients receiving propofol for extended periods may result in excessively high blood concentrations of the drug. Thus, titration to clinical response and daily evaluation of sedation levels are important during use of propofol infusion for ICU sedation, especially when it is used for long durations.
Opioids and paralytic agents should be discontinued and respiratory function optimized prior to weaning patients from mechanical ventilation. Infusions of propofol should be adjusted to maintain a light level of sedation prior to weaning patients from mechanical ventilatory support. Throughout the weaning process, this level of sedation may be maintained in the absence of respiratory depression. Because of the rapid clearance of propofol, abrupt discontinuation of a patient's infusion may result in rapid awakening with associated anxiety, agitation, and resistance to mechanical ventilation, making weaning from mechanical ventilation difficult. It is therefore recommended that administration of propofol be continued in order to maintain a light level of sedation throughout the weaning process until 10 minutes to 15 minutes prior to extubation, at which time the infusion can be discontinued.
Since propofol injectable emulsion is formulated in an oil-in-water emulsion, elevations in serum triglycerides may occur when propofol is administered for extended periods of time. Patients at risk of hyperlipidemia should be monitored for increases in serum triglycerides or serum turbidity. Administration of propofol should be adjusted if fat is being inadequately cleared from the body. A reduction in the quantity of concurrently administered lipids is indicated to compensate for the amount of lipid infused as part of the propofol formulation; 1 mL of propofol contains approximately 0.1 g of fat (1.1 kcal).
The long-term administration of propofol to patients with renal failure and/or hepatic insufficiency has not been evaluated.
Most adult patients under 55 years of age and classified as ASA-PS I or II require 2 mg/kg to 2.5 mg/kg of propofol for induction when unpremedicated or when premedicated with oral benzodiazepines or intramuscular opioids. For induction, propofol should be titrated (approximately 40 mg every 10 seconds) against the response of the patient until the clinical signs show the onset of anesthesia. As with other general anesthetics, the amount of intravenous opioid and/or benzodiazepine premedication will influence the response of the patient to an induction dose of propofol.
In adults, anesthesia can be maintained by administering propofol by infusion or intermittent IV bolus injection. The patient's clinical response will determine the infusion rate or the amount and frequency of incremental injections.
When propofol is administered for MAC sedation, rates of administration should be individualized and titrated to clinical response. In most patients, the rates of propofol injectable emulsion administration will be in the range of 25 mcg/kg/min to 75 mcg/kg/min.
During initiation of MAC sedation, slow infusion or slow injection techniques are preferable over rapid bolus administration. During maintenance of MAC sedation, a variable rate infusion is preferable over intermittent bolus dose administration. In the elderly, debilitated, or ASA-PS III or IV patients, rapid (single or repeated) bolus dose administration should not be used for MAC sedation. (See WARNINGS.) A rapid bolus injection can result in undesirable cardiorespiratory depression including hypotension, apnea, airway obstruction, and oxygen desaturation.
For intubated, mechanically ventilated adult patients, Intensive Care Unit (ICU) sedation should be initiated slowly with a continuous infusion in order to titrate to desired clinical effect and minimize hypotension. (See DOSAGE AND ADMINISTRATION.)
Most adult ICU patients recovering from the effects of general anesthesia or deep sedation will require maintenance rates of 5 mcg/kg/min to 50 mcg/kg/min (0.3 mg/kg/h to 3 mg/kg/h) individualized and titrated to clinical response. (See DOSAGE AND ADMINISTRATION.) With medical ICU patients or patients who have recovered from the effects of general anesthesia or deep sedation, the rate of administration of 50 mcg/kg/min or higher may be required to achieve adequate sedation. These higher rates of administration may increase the likelihood of patients developing hypotension. Administration should not exceed 4 mg/kg/hour unless the benefits outweight the risks. (See WARNINGS.)
Dosage and rate of administration should be individualized and titrated to the desired effect, according to clinically relevant factors including the patient’s underlying medical problems, preinduction and concomitant medications, age, ASA-PS classification, and level of debilitation of the patient. The elderly, debilitated, and ASA-PS III or IV patients may have exaggerated hemodynamic and respiratory responses to rapid bolus doses. (See WARNINGS.)
Propofol should be individualized according to the patient's condition and response, blood lipid profile, and vital signs. (See PRECAUTIONS - Intensive Care Unit Sedation.) For intubated, mechanically ventilated adult patients, Intensive Care Unit (ICU) sedation should be initiated slowly with a continuous infusion in order to titrate to desired clinical effect and minimize hypotension. When indicated, initiation of sedation should begin at 5 mcg/kg/min (0.3 mg/kg/h). The infusion rate should be increased by increments of 5 mcg/kg/min to 10 mcg/kg/min (0.3 mg/kg/h to 0.6 mg/kg/h) until the desired level of sedation is achieved. A minimum period of 5 minutes between adjustments should be allowed for onset of peak drug effect. Most adult patients require maintenance rates of 5 mcg/kg/min to 50 mcg/kg/min (0.3 mg/kg/h to 3 mg/kg/h) or higher. Administration should not exceed 4 mg/kg/hour unless the benefits outweigh the risks (see WARNINGS). Dosages of propofol should be reduced in patients who have received large dosages of narcotics. The propofol dosage requirement may also be reduced by adequate management of pain with analgesic agents. As with other sedative medications, there is interpatient variability in dosage requirements, and these requirements may change with time. (See SUMMARY OF DOSAGE GUIDELINES.) Evaluation of level of sedation and assessment of CNS function should be carried out daily throughout maintenance to determine the minimum dose of propofol required for sedation (see Clinical Trials - Intensive Care Unit (ICU) Sedation). Bolus administration of 10 mg or 20 mg should only be used to rapidly increase depth of sedation in patients where hypotension is not likely to occur. Patients with compromised myocardial function, intravascular volume depletion, or abnormally low vascular tone (e.g., sepsis) may be more susceptible to hypotension. (See PRECAUTIONS.)