Cisatracurium Besylate

Approved Indications:

• Facilitation of Endotracheal Intubation during anesthesia induction.
• Maintenance of Skeletal Muscle Relaxation during general anesthesia in elective surgery (e.g., abdominal, thoracic procedures).
• Facilitation of Mechanical Ventilation in intensive care patients requiring sedation and neuromuscular blockade.

Off‑Label / Clinically Accepted Uses:

• Adjunct in rapid‑sequence induction when used with appropriate doses.
• In ICU: to control shivering, reduce oxygen consumption, or optimize ventilator synchrony.
• Rarely used in electroconvulsive therapy (ECT) to reduce motor convulsions (specialist use).

Adults:

• Intubation dose (IV): 0.15–0.2 mg/kg (3×ED95) administered ~ 2–3 min prior to intubation.
• Maintenance infusion: 1–3 µg/kg/min IV infusion, or intermittent 0.03 mg/kg boluses every 20–40 minutes as needed.

Elderly / Critically Ill:

• Lower initial dose may be needed (0.1–0.15 mg/kg) due to reduced volume of distribution and potential organ dysfunction.

Pediatrics (≥1 month):

• Intubation: 0.1–0.2 mg/kg IV.
• Infusion: 1–3 µg/kg/min, titrated based on neuromuscular monitoring.

Special Groups:

• Renal or Hepatic Impairment: No dose adjustment needed—metabolism is organ‑independent via Hofmann degradation.
• Obese Patients: Dosing based on ideal body weight.

Administration Route: IV injection or infusion through dedicated line; compatibility checked with IV fluids.

Cisatracurium is a non-depolarizing neuromuscular blocking agent of the benzylisoquinolinium class. It competitively binds to post‑junctional nicotinic acetylcholine receptors at the neuromuscular junction, preventing acetylcholine from activating muscle contraction. The result is flaccid, reversible skeletal muscle paralysis. Its intermediate duration and reduced release of histamine yield stable cardiovascular effects while facilitating intubation and surgical paralysis.

• Absorption/Distribution: Administered IV; onset of action ~2–3 minutes; peak effect at ~3–5 minutes. Volume of distribution ~0.3 L/kg.
• Metabolism: Undergoes Hofmann elimination (temperature/pH‑dependent organ‑independent degradation) to laudanosine and a quaternary acid. Minor ester hydrolysis contributes little.
• Active Metabolites: Laudanosine is weakly active centrally and accumulates in renal failure but generally clinically insignificant.
• Elimination: Primarily non‑enzymatic. Excreted via renal (>30 %) and minor biliary routes.
• Half‑Life: ~20–30 minutes; context-sensitive half-life supports predictable recovery.
• Onset/Duration: Onset within 2–3 min, clinical duration ~45–60 min (single bolus), recovery without infusion in ~90 min.

• Pregnancy: No formal FDA category. Limited data; use only if benefits outweigh risks. The drug does not cross the placental barrier significantly and is only used intraoperatively.
• Lactation: No data; systemic exposure is minimal and short-lived. Not expected to affect breastfed infants.

• Primary Class: Neuromuscular Blocking Agent
• Subclass: Non‑depolarizing benzylisoquinolinium neuromuscular blocker, intermediate‑acting

• Known hypersensitivity to cisatracurium or any benzylisoquinolinium compound.
• Acute porphyria (rare cases reported with neuromuscular blockers).
• Patients with myasthenia gravis or other neuromuscular transmission disorders without adjustment and monitoring.

• Use neuromuscular monitoring (e.g., train-of-four) to guide dosing and recovery.
• Residual paralysis risk—ensure full reversal before extubation to avoid respiratory complications.
• Laudanosine accumulation may cause seizures in patients with high-dose infusions or impaired elimination (rare).
• Avoid inadvertent histamine release (minimal with this agent), but monitor hypotension or bronchospasm.
• Hypothermia or acidosis (in ICU) may slow Hofmann degradation and prolong paralysis.
• Use cautiously in patients with severe acid–base disturbances.

Common:

• Rare histamine-mediated flushing, hypotension—less frequent than older agents.
• Mild bradycardia or transient tachycardia.

Less Common / Rare:

• Laudanosine-related CNS excitatory signs (tremor, convulsions) with massive prolonged infusion.
• Allergic reactions (urticaria, rare anaphylaxis).
• Residual neuromuscular blockade—leading to respiratory insufficiency if not reversed properly.

Timing:

• Hemodynamic effects may appear within minutes; residual weakness may persist post-infusion if monitoring is inadequate.

• Aminoglycosides, inhaled anesthetics, magnesium, tetracyclines: Potentiate neuromuscular block; reduce dose accordingly.
• Lithium: May enhance neuromuscular blockade.
• Corticosteroids (long-term): May induce resistance to neuromuscular blockade (rare).
• No involvement of CYP enzymes—interactions reflect pharmacodynamic synergy, not metabolic metabolism.

• ASA Practice Guidelines (2024): Recommend objective neuromuscular monitoring and full reversal before extubation to minimize postoperative residual blockade.
• Critical Care Bundles (2023): Prefer cisatracurium infusion in ARDS patients requiring paralysis due to predictable metabolism and minimal organ dependence.
• FDA Alerts (2023): Emphasis on avoidance of prolonged neuromuscular block in ICU without monitoring and sedation levels.

• Store at 2 °C to 8 °C (refrigerated).
• Protect from light.
• Do not freeze.
• Solution should be stored in sealed vials; once opened, use promptly as per manufacturer instructions.
• Inspect visually—discard if discolored or particulate matter present.
• Keep out of reach of children.