Propofol blood concentrations at steady-state are generally proportional to infusion rates, especially in individual patients. Undesirable effects such as cardiorespiratory depression are likely to occur at higher blood concentrations which result from bolus dosing or rapid increases in the infusion rate. An adequate interval (3 minutes to 5 minutes) must be allowed between dose adjustments to allow for and assess the clinical effects.
Shake well before use. Do not use if there is evidence of excessive creaming or aggregation, if large droplets are visible, or if there are other forms of phase separation indicating that the stability of the product has been compromised. Slight creaming, which should disappear after shaking, may be visible upon prolonged standing.
When administering propofol injectable emulsion by infusion, syringe or volumetric pumps are recommended to provide controlled infusion rates. When infusing propofol injectable emulsion to patients undergoing magnetic resonance imaging, metered control devices may be utilized if mechanical pumps are impractical.
Changes in vital signs indicating a stress response to surgical stimulation or the emergence from anesthesia may be controlled by the administration of 25 mg (2.5 mL) to 50 mg (5 mL) incremental boluses and/or by increasing the infusion rate of propofol injectable emulsion.
For minor surgical procedures (e.g., body surface) nitrous oxide (60% to 70%) can be combined with a variable rate propofol injectable emulsion infusion to provide satisfactory anesthesia. With more stimulating surgical procedures (e.g., intra-abdominal), or if supplementation with nitrous oxide is not provided, administration rate(s) of propofol injectable emulsion and/or opioids should be increased in order to provide adequate anesthesia.
Infusion rates should always be titrated downward in the absence of clinical signs of light anesthesia until a mild response to surgical stimulation is obtained in order to avoid administration of propofol injectable emulsion at rates higher than are clinically necessary. Generally, rates of 50 mcg/kg/min to 100 mcg/kg/min in adults should be achieved during maintenance in order to optimize recovery times.
Other drugs that cause CNS depression (e.g., sedatives, anesthetics, and opioids) can increase CNS depression induced by propofol. Morphine premedication (0.15 mg/kg) with nitrous oxide 67% in oxygen has been shown to decrease the necessary propofol injection maintenance infusion rate and therapeutic blood concentrations when compared to non-narcotic (lorazepam) premedication.
Induction of General Anesthesia
Adult Patients
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 injectable emulsion for induction when unpremedicated or when premedicated with oral benzodiazepines or intramuscular opioids. For induction, propofol injectable emulsion 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 injectable emulsion.
Elderly, Debilitated, or ASA-PS III or IV Patients
It is important to be familiar and experienced with the intravenous use of propofol injectable emulsion before treating elderly, debilitated, or ASA-PS III or IV patients. Due to the reduced clearance and higher blood concentrations, most of these patients require approximately 1 mg/kg to 1.5 mg/kg (approximately 20 mg every 10 seconds) of propofol injectable emulsion for induction of anesthesia according to their condition and responses. A rapid bolus should not be used, as this will increase the likelihood of undesirable cardiorespiratory depression including hypotension, apnea, airway obstruction, and/or oxygen desaturation (see DOSAGE AND ADMINISTRATION).
Pediatric Patients
Most patients aged 3 years through 16 years and classified ASA-PS I or II require 2.5 mg/kg to 3.5 mg/kg of propofol injectable emulsion for induction when unpremedicated or when lightly premedicated with oral benzodiazepines or intramuscular opioids. Within this dosage range, younger pediatric patients may require higher induction doses than older pediatric patients. 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 injectable emulsion. A lower dosage is recommended for pediatric patients classified as ASA-PS III or IV. Attention should be paid to minimize pain on injection when administering propofol injectable emulsion to pediatric patients. Boluses of propofol injectable emulsion may be administered via small veins if pretreated with lidocaine or via antecubital or larger veins (see PRECAUTIONS, General).
Neurosurgical Patients
Slower induction is recommended using boluses of 20 mg every 10 seconds. Slower boluses or infusions of propofol injectable emulsion for induction of anesthesia, titrated to clinical responses, will generally result in reduced induction dosage requirements (1 mg/kg to 2 mg/kg) (see PRECAUTIONS and DOSAGE AND ADMINISTRATION).
Cardiac Anesthesia
Propofol injectable emulsion has been well–studied in patients with coronary artery disease, but experience in patients with hemodynamically significant valvular or congenital heart disease is limited. As with other general anesthetics and sedation drugs, propofol injectable emulsion in healthy patients causes a decrease in blood pressure that is secondary to decreases in preload (ventricular filling volume at the end of the diastole) and afterload (arterial resistance at the beginning of the systole). The magnitude of these changes is proportional to the blood and effect site concentrations achieved. These concentrations depend upon the dose and speed of the induction and maintenance infusion rates.
In addition, lower heart rates are observed during maintenance with propofol injectable emulsion, possibly due to reduction of the sympathetic activity and/or resetting of the baroreceptor reflexes. Therefore, anticholinergic agents should be administered when increases in vagal tone are anticipated.
As with other anesthetic agents, propofol injectable emulsion reduces myocardial oxygen consumption. Further studies are needed to confirm and delineate the extent of these effects on the myocardium and the coronary vascular system.
Morphine premedication (0.15 mg/kg) with nitrous oxide 67% in oxygen has been shown to decrease the necessary propofol injectable emulsion maintenance infusion rates and therapeutic blood concentrations when compared to non–narcotic (lorazepam) premedication. The rate of propofol injectable emulsion administration should be determined based on the patient's premedication and adjusted according to clinical responses.
A rapid bolus induction should be avoided. A slow rate of approximately 20 mg every 10 seconds until induction onset (0.5 mg/kg to 1.5 mg/kg) should be used. In order to assure adequate anesthesia, when propofol injectable emulsion is used as the primary agent, maintenance infusion rates should not be less than 100 mcg/kg/min and should be supplemented with analgesic levels of continuous opioid administration. When an opioid is used as the primary agent, propofol injectable emulsion maintenance rates should not be less than 50 mcg/kg/min, and care should be taken to ensure amnesia. Higher doses of propofol injectable emulsion will reduce the opioid requirements (see Table 4). When propofol injectable emulsion is used as the primary anesthetic, it should not be administered with the high-dose opioid technique as this may increase the likelihood of hypotension (see PRECAUTIONS, Cardiac Anesthesia).
Table 4. Cardiac Anesthesia Techniques |
|
|
|
|
|
Primary Agent
| Rate
| Secondary Agent/Rate (Following Induction with Primary Agent)
|
Propofol injectable emulsion
| | OPIOIDa/0.05 mcg/kg/min to 0.075 mcg/kg/min (no bolus)
|
Preinduction Anxiolysis
| 25 mcg/kg/min
| |
Induction
| 0.5 mg/kg over 60 sec
| |
Maintenance (Titrated to Clinical Response)
| 100 mcg/kg/min
| |
OPIOIDb
| | Propofol injectable emulsion/50 mcg/kg/min (no bolus)
|
Induction
| 25 mcg/kg
| |
Maintenance
| 0.2 mcg/kg/min
| |
Maintenance of General Anesthesia
Propofol injectable emulsion has been used with a variety of agents commonly used in anesthesia such as atropine, scopolamine, glycopyrrolate, diazepam, depolarizing and nondepolarizing muscle relaxants, and opioid analgesics, as well as with inhalational and regional anesthetic agents.
In the elderly, debilitated, or ASA-PS III or IV patients, rapid bolus doses should not be used, as this will increase cardiorespiratory effects including hypotension, apnea, airway obstruction, and oxygen desaturation.
Adult Patients
In adults, anesthesia can be maintained by administering propofol injectable emulsion 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.
Continuous Infusion
Propofol injectable emulsion 100 mcg/kg/min to 200 mcg/kg/min administered in a variable rate infusion with 60% to 70% nitrous oxide and oxygen provides anesthesia for patients undergoing general surgery. Maintenance by infusion of propofol injectable emulsion should immediately follow the induction dose in order to provide satisfactory or continuous anesthesia during the induction phase. During this initial period following the induction dose, higher rates of infusion are generally required (150 mcg/kg/min to 200 mcg/kg/min) for the first 10 minutes to 15 minutes. Infusion rates should subsequently be decreased 30% to 50% during the first half-hour of maintenance. Generally, rates of 50 mcg/kg/min to 100 mcg/kg/min in adults should be achieved during maintenance in order to optimize recovery times.
Other drugs that cause CNS depression (e.g., sedatives, anesthetics, and opioids) can increase the CNS depression induced by propofol.
Intermittent Bolus
Increments of propofol injectable emulsion 25 mg (2.5 mL) to 50 mg (5 mL) may be administered with nitrous oxide in adult patients undergoing general surgery. The incremental boluses should be administered when changes in vital signs indicate a response to surgical stimulation or light anesthesia.
Pediatric Patients
Propofol injectable emulsion administered as a variable rate infusion supplemented with nitrous oxide 60% to 70% provides satisfactory anesthesia for most children 2 months of age or older, ASA-PS I or II, undergoing general anesthesia.
In general, for the pediatric population, maintenance by infusion of propofol injectable emulsion at a rate of 200 mcg/kg/min to 300 mcg/kg/min should immediately follow the induction dose. Following the first half-hour of maintenance, infusion rates of 125 mcg/kg/min to 150 mcg/kg/min are typically needed. Propofol injectable emulsion should be titrated to achieve the desired clinical effect. Younger pediatric patients may require higher maintenance infusion rates than older pediatric patients. (See Table 2 Clinical Trials.)
Monitored Anesthesia Care (MAC) Sedation
Adult Patients
When propofol injectable emulsion 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.
Initiation of MAC Sedation
For initiation of MAC sedation, either an infusion or a slow injection method may be utilized while closely monitoring cardiorespiratory function. With the infusion method, sedation may be initiated by infusing propofol injectable emulsion at 100 mcg/kg/min to 150 mcg/kg/min (6 mg/kg/h to 9 mg/kg/h) for a period of 3 minutes to 5 minutes and titrating to the desired clinical effect while closely monitoring respiratory function. With the slow injection method for initiation, patients will require approximately 0.5 mg/kg administered over 3 minutes to 5 minutes and titrated to clinical responses. When propofol injectable emulsion is administered slowly over 3 minutes to 5 minutes, most patients will be adequately sedated, and the peak drug effect can be achieved while minimizing undesirable cardiorespiratory effects occurring at high plasma levels.
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). The rate of administration should be over 3 minutes to 5 minutes and the dosage of propofol injectable emulsion should be reduced to approximately 80% of the usual adult dosage in these patients according to their condition, responses, and changes in vital signs (see DOSAGE AND ADMINISTRATION).
Maintenance of MAC Sedation
For maintenance of sedation, a variable rate infusion method is preferable over an intermittent bolus dose method. With the variable rate infusion method, patients will generally require maintenance rates of 25 mcg/kg/min to 75 mcg/kg/min (1.5 mg/kg/h to 4.5 mg/kg/h) during the first 10 minutes to 15 minutes of sedation maintenance. Infusion rates should subsequently be decreased over time to 25 mcg/kg/min to 50 mcg/kg/min and adjusted to clinical responses. In titrating to clinical effect, allow approximately 2 minutes for onset of peak drug effect.
Infusion rates should always be titrated downward in the absence of clinical signs of light sedation until mild responses to stimulation are obtained in order to avoid sedative administration of propofol injectable emulsion at rates higher than are clinically necessary.
If the intermittent bolus dose method is used, increments of propofol injectable emulsion 10 mg (1 mL) or 20 mg (2 mL) can be administered and titrated to desired clinical effect. With the intermittent bolus method of sedation maintenance, there is increased potential for respiratory depression, transient increases in sedation depth, and prolongation of recovery.
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). The rate of administration and the dosage of propofol injectable emulsion should be reduced to approximately 80% of the usual adult dosage in these patients according to their condition, responses, and changes in vital signs (see DOSAGE AND ADMINISTRATION).
Propofol injectable emulsion can be administered as the sole agent for maintenance of MAC sedation during surgical/diagnostic procedures. When propofol injectable emulsion sedation is supplemented with opioid and/or benzodiazepine medications, these agents increase the sedative and respiratory effects of propofol injectable emulsion and may also result in a slower recovery profile (see PRECAUTIONS, Drug Interactions).
ICU Sedation
(See WARNINGS and DOSAGE AND ADMINISTRATION, Handling Procedures.)
Abrupt discontinuation of propofol injectable emulsion prior to weaning or for daily evaluation of sedation levels should be avoided. This may result in rapid awakening with associated anxiety, agitation, and resistance to mechanical ventilation. Infusions of propofol injectable emulsion should be adjusted to assure a minimal level of sedation is maintained throughout the weaning process and when assessing the level of sedation (see PRECAUTIONS).
Adult Patients
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 outweigh 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 injectable emulsion 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 injectable emulsion should be reduced in patients who have received large dosages of narcotics. The propofol injectable emulsion 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 injectable emulsion 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).