Paralytics can help with oxygenation, ventilation or dyssynchrony during mechanical ventilation by reducing metabolic demands and CO2 production, and by increasing chest compliance.
- Consider using paralytics for early severe ARDS (significant practice pattern variation remains).
- Based on 2013 meta-analysis, short-term infusion of cisatracurium besylate reduces hospital mortality and barotrauma and does not appear to increase ICU-acquired weakness for critically ill adults with ARDS.
- In contrast, the ROSE trial (2019) suggested no mortality benefit at 90 days to early continuous paralysis.
- Possible side effects: histamine release (succinylcholine), hypotension, tachycardia, bronchospasm, malignant hyperthermia (treat with dantrolene), and prolonged paralysis.
- Paralytics must be used with a sedation regimen that provides reliable amnesia (e.g. propofol or midazolam) that should not be titrated down while the patient is paralyzed.
- Avoid prolonged (>48 hours) continuous infusion of paralytics if possible, particularly in patients on corticosteroids, due to the risk of critical illness myopathy/neuropathy and pneumonia. Try to discontinue when possible.
- Train-of-Four monitoring: titrate dose of paralytics to maintain >1/4 twitches.
| Agent | Dose | Advantages | Disadvantages | Contraindications | |
|---|---|---|---|---|---|
|
|
Bolus |
Infusion |
|
|
|
|
Vecuronium |
0.1 mg/kg |
0.8-1.5 mcg/kg/min |
Minimal cardiovascular effects |
Longer acting |
Liver dysfunction Caution in kidney disease |
|
Cisatracurium “Nimbex” |
0.15-0.2 mg/kg |
1-4 mcg/kg/min |
Can be used in hepatic and renal failure (Hoffman elimination) Short acting |
Expensive Not always readily available |
None |
- Both vecuronium and cisatracurium are relatively slow in onset, and so therefore not used for induction in RSI. For short-acting paralytics, see section Rapid Sequence Intubation.
Alhazzani W, Alshahrani M, Jaeschke R, et al. Neuromuscular blocking agents in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials. Crit Care. 2013 Mar 11;17(2):R43.
Murray MJ, Cowen J, DeBlock H, et al. Clinical practice guidelines for sustained neuromuscular blockade in the adult critically ill patient. Crit Care Med 2002; 30:142-156.
National Heart L, Blood Institute PCTN, Moss M, Huang DT, Brower RG, Ferguson ND, Ginde AA, Gong MN, Grissom CK, Gundel S, et al. Early neuromuscular blockade in the acute respiratory distress syndrome. N Engl J Med. 2019;380:1997–2008.
Papazian L, Forel JM, et al. Neuromuscular Blockers in Early Acute Respiratory Distress Syndrome. N Engl J Med 2010; 363:1107-1116.
Segredo V, Caldwell JE, Matthay MA, et al. Persistent paralysis in critically ill patients after long-term administration of vecuronium. N Engl J Med 1992; 327:524-528.