Important Dosage and Administration Instructions

Important administration instructions include:

• NIMBEX is for intravenous use only.
• Administer NIMBEX in carefully adjusted dosage by or under the supervision of experienced clinicians who are familiar with the drug’s actions and the possible complications.
• Use NIMBEX only if the following are immediately available: personnel and facilities for resuscitation and life support (tracheal intubation, artificial ventilation, oxygen therapy); and an antagonist of NIMBEX [see Overdosage (10)].
• The dosage information which follows is intended to serve as an initial guide for individual patients; base subsequent NIMBEX dosage on the patients’ responses to the initial doses.
• Use a peripheral nerve stimulator to:
  • Determine the adequacy of neuromuscular blockade (e.g., need for additional NIMBEX doses, reduction of the infusion rate).
  • Minimize risk of overdosage or underdosage.
  • Assess the extent of recovery from neuromuscular blockade (e.g., spontaneous recovery or recovery after administration of a reversal agent, e.g., neostigmine).
  • Appropriately titrate doses to potentially limit exposure to toxic metabolites.
  • Facilitate more rapid reversal of the NIMBEX-induced paralysis.

Risk of Medication Errors

Accidental administration of neuromuscular blocking agents may be fatal. Store NIMBEX with the cap and ferrule intact and in a manner that minimizes the possibility of selecting the wrong product [see Warnings and Precautions (5.5)].

Recommended NIMBEX Dose for Performing Tracheal Intubation

Tracheal Intubation in Adults

Prior to selecting the initial NIMBEX bolus dose, consider the desired time to tracheal intubation and the anticipated length of surgery, factors affecting time to onset of complete neuromuscular block such as age and renal function, and factors that may influence intubation conditions such as the presence of co-induction agents (e.g., fentanyl and midazolam) and the depth of anesthesia.

In conjunction with a propofol/nitrous oxide/oxygen induction-intubation technique or a thiopental/nitrous oxide/oxygen induction-intubation technique, the recommended starting weight-based dose of NIMBEX is between 0.15 mg/kg and 0.2 mg/kg administered by bolus intravenous injection. Doses up to 0.4 mg/kg have been safely administered by bolus intravenous injection to healthy patients and patients with serious cardiovascular disease [see Clinical Pharmacology (12.2)].

Patients with Neuromuscular Disease

The maximum recommended initial bolus dose of NIMBEX is 0.02 mg/kg in patients with neuromuscular diseases (e.g., myasthenia gravis and myasthenic syndrome and carcinomatosis) [see Warnings and Precautions (5.1)].

Geriatric Patients and Patients with End-Stage Renal Disease

Because the time to maximum neuromuscular blockade is approximately 1 minute slower in geriatric patients compared to younger patients (and in patients with end-stage renal disease than in patients with normal renal function), consider extending the interval between administering NIMBEX and attempting intubation by at least 1 minute to achieve adequate intubation conditions in geriatric patients and patients with end-stage renal disease. A peripheral nerve stimulator should be used to determine the adequacy of muscle relaxation for the purposes of intubation and the timing and amounts of subsequent doses [see Use in Specific Populations (8.5, 8.6) and Clinical Pharmacology (12.3)].

Tracheal Intubation in Pediatric Patients

Infants 1 to 23 Months of Age

The recommended dose of NIMBEX for intubation of pediatric patients ages 1 month to 23 months is 0.15 mg/kg administered over 5 to 10 seconds. When administered during stable opioid/nitrous oxide/oxygen anesthesia, 0.15 mg/kg of NIMBEX produced maximum neuromuscular blockade in about 2 minutes (range: 1.3 to 4.3 minutes) with a clinically effective block (time to 25% recovery) for about 43 minutes (range: 34 to 58 minutes) [see Clinical Studies (14.2)].

Pediatric Patients 2 to 12 Years of Age

The recommended weight-based bolus dose of NIMBEX for pediatric patients 2 to 12 years of age is 0.1 to 0.15 mg/kg administered over 5 to 10 seconds. When administered during stable opioid/nitrous oxide/oxygen anesthesia, 0.1 mg/kg NIMBEX produced maximum neuromuscular blockade in an average of 2.8 minutes (range: 1.8 to 6.7 minutes) with a clinically effective block (time to 25% recovery) for 28 minutes (range: 21 to 38 minutes). When administered during stable opioid/nitrous oxide/oxygen anesthesia, 0.15 mg/kg NIMBEX produced maximum neuromuscular blockade in an average of about 3 minutes (range: 1.5 to 8 minutes) with a clinically effective block for 36 minutes (range: 29 to 46 minutes) [see Clinical Studies (14.2)].

Recommended Maintenance Bolus NIMBEX Doses in Adult Surgical Procedures

Determine if maintenance bolus doses are needed based on clinical criteria including the response to peripheral nerve stimulation. The recommended maintenance bolus dose of NIMBEX is 0.03 mg/kg; however, smaller or larger maintenance doses may be administered based on the required duration of action. Administer the first maintenance bolus dose starting:

• 40 to 50 minutes after an initial dose of NIMBEX 0.15 mg/kg;
• 50 to 60 minutes after an initial dose of NIMBEX 0.2 mg/kg.

For long surgical procedures using inhalational anesthetics administered with nitrous oxide/oxygen at the 1.25 MAC level for at least 30 minutes, consider administering less frequent maintenance bolus doses or lower maintenance bolus doses of NIMBEX [see Clinical Pharmacology (12.2)]. No adjustment to the initial NIMBEX maintenance bolus dose should be necessary when NIMBEX is administered shortly after initiation of volatile agents or when used in patients receiving propofol anesthesia.

Dosage in Burn Patients

Burn patients have been shown to develop resistance to nondepolarizing neuromuscular blocking agents; therefore, consider increasing the NIMBEX dosages for intubation and maintenance [see Use in Specific Populations (8.8)].

Dosage for Continuous Infusion

Continuous Infusion for Surgical Procedures in Adults and Pediatric Patients

During extended surgical procedures, NIMBEX may be administered by continuous infusion to adults and pediatric patients aged 2 or more years if patients have spontaneous recovery after the initial NIMBEX bolus dose. Following recovery from neuromuscular blockade, it may be necessary to re-administer a bolus dose to quickly re-establish neuromuscular blockade prior to starting the continuous infusion.

If patients have had recovery of neuromuscular function, the recommended initial NIMBEX infusion rate is 3 mcg/kg/minute [see Dosage and Administration (2.6)]. Subsequently reduce the rate to 1 to 2 mcg/kg/minute to maintain continuous neuromuscular blockade. Use peripheral nerve stimulation to assess the level of neuromuscular blockade and to appropriately titrate the NIMBEX infusion rate. If no response is elicited to peripheral nerve stimulation, discontinue the infusion until a response returns.

Consider reducing the infusion rate by up to 30% to 40% when NIMBEX is administered during stable isoflurane anesthesia for at least 30 minutes (administered with nitrous oxide/oxygen at the 1.25 MAC level) [see Clinical Pharmacology (12.2)]. Greater reductions in the NIMBEX infusion rate may be required with longer durations of administration of isoflurane or with the administration of other inhalational anesthetics.

Patients Undergoing Coronary Artery Bypass Graft (CABG) Surgery

Consider reducing the infusion rate in patients undergoing CABG with induced hypothermia to half the rate required during normothermia [see Clinical Pharmacology (12.2)]. Spontaneous recovery from neuromuscular block following discontinuation of NIMBEX infusion is expected to proceed at a rate comparable to that following administration of a single bolus dose.

Continuous Infusion for Mechanical Ventilation in the Intensive Care Unit in Adults

During extended need for mechanical ventilation and skeletal muscle relaxation in the intensive care unit (ICU), NIMBEX may be administered by continuous infusion to adults if a patient has spontaneous recovery of neuromuscular function after the initial NIMBEX bolus dose. Following recovery from neuromuscular blockade, it may be necessary to re-administer a bolus dose to quickly re-establish neuromuscular blockade prior to starting the continuous infusion.

The recommended NIMBEX infusion rate in adult patients in the ICU is 3 mcg/kg/minute (range: 0.5 to 10.2 mcg/kg/minute) [see Dosage and Administration (2.6)]. Use peripheral nerve stimulation to assess the level of neuromuscular blockade and to appropriately titrate the NIMBEX infusion rate.

Rate Tables for Continuous Infusion

The intravenous infusion rate depends upon the NIMBEX concentration, the desired dose, the patient's weight, and the contribution of the infusion solution to the fluid requirements of the patient. Tables 1 and 2 provide guidelines for the NIMBEX infusion rate, in mL/hour (equivalent to microdrops/minute when 60 microdrops = 1 mL), in concentrations of 0.1 mg/mL or 0.4 mg/mL, respectively.

Preparation of NIMBEX

Visually inspect NIMBEX for particulate matter and discoloration prior to administration. If a NIMBEX solution is cloudy or contains visible particulates, do not use NIMBEX. NIMBEX is a colorless to slightly yellow or greenish-yellow solution.

​Discard unused portion of the 5 mL and 20 mL single-dose vials.

NIMBEX may be diluted to 0.1 mg/mL in the following solutions:

• 5% Dextrose Injection, USP
• 0.9% Sodium Chloride Injection, USP, or
• 5% Dextrose and 0.9% Sodium Chloride Injection, USP

Store these diluted NIMBEX solutions either in a refrigerator or at room temperature for 24 hours without significant loss of potency.

NIMBEX also may be diluted to 0.1 mg/mL or 0.2 mg/mL in the following solution:

• Lactated Ringer’s and 5% Dextrose Injection

Store this diluted NIMBEX solution under refrigeration for no more than 24 hours.

Do not dilute NIMBEX in Lactated Ringer’s Injection, USP due to chemical instability.

Drug Compatibility

NIMBEX is compatible and may be administered with the following solutions through Y-site administration:

• 5% Dextrose Injection, USP
• 0.9% Sodium Chloride Injection, USP
• 5% Dextrose and 0.9% Sodium Chloride Injection, USP
• Sufentanil Citrate Injection, diluted as directed
• Alfentanil Hydrochloride Injection, diluted as directed
• Fentanyl Citrate Injection, diluted as directed
• Midazolam Hydrochloride Injection, diluted as directed
• Droperidol Injection, diluted as directed

NIMBEX is acidic (pH = 3.25 to 3.65) and may not be compatible with alkaline solution having a pH greater than 8.5 (e.g., barbiturate solutions). Therefore, do not administer NIMBEX and alkaline solutions simultaneously in the same intravenous line.

NIMBEX is not compatible with propofol injection or ketorolac injection for Y-site administration. Compatibility studies with other parenteral products have not been conducted.