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Drugs to Aid Intubation


Vanessa Moll

, MD, DESA, Emory University School of Medicine, Department of Anesthesiology, Division of Critical Care Medicine

Reviewed/Revised Apr 2023

Pulseless and apneic or severely obtunded patients can (and should) be intubated without pharmacologic assistance. Other patients are given sedating and paralytic drugs to minimize discomfort and facilitate intubation (termed rapid sequence intubation).

Pretreatment before intubation

Pretreatment typically includes

  • 100% oxygen

  • Lidocaine and/or fentanyl

  • Sometimes atropine, a neuromuscular blocker, or both

If time permits, patients should be placed on 100% oxygen for 3 to 5 minutes; this measure may maintain satisfactory oxygenation in previously healthy patients for up to 8 minutes. Noninvasive ventilation (NIV) or high-flow nasal cannula (HFNC) can be used to aid preoxygenation (1 General references Pulseless and apneic or severely obtunded patients can (and should) be intubated without pharmacologic assistance. Other patients are given sedating and paralytic drugs to minimize discomfort... read more ). Even in apneic patients, such preoxygenation has been shown to improve arterial oxygen saturation and prolong the period of safe apneic time (2 General references Pulseless and apneic or severely obtunded patients can (and should) be intubated without pharmacologic assistance. Other patients are given sedating and paralytic drugs to minimize discomfort... read more ). However, oxygen demand and safe apnea times are very dependent on pulse rate, pulmonary function, red blood cell count, and numerous other metabolic factors.

Laryngoscopy can stimulate coughing and causes a sympathetic-mediated pressor response with an increase in heart rate, blood pressure, and possibly intracranial pressure. When time permits, some practitioners give lidocaine 1.5 mg/kg IV 1 to 2 minutes before sedation and paralysis to decrease coughing and possibly to decrease the sympathetic-mediated pressor response, although the evidence is mixed. Fentanyl (eg, 3 to 5 mcg/kg IV), also given 1 to 2 minutes prior to intubation, may also blunt the increase sympathetic-mediated pressor response.

Children and adolescents often have a vagal response (marked bradycardia) in response to intubation and are given atropine 0.02 mg/kg IV (minimum: 0.1 mg in infants, 0.5 mg in children and adolescents) at the same time.

Some physicians include a small dose of a neuromuscular blocker, such as vecuronium 0.01 mg/kg IV, in patients > 4 years to prevent muscle fasciculations caused by full doses of succinylcholine. Fasciculations may result in muscle pain on awakening and cause transient hyperkalemia; however, the actual benefit of such pretreatment is unclear.

Sedation and analgesia for intubation

Laryngoscopy and intubation are uncomfortable; in conscious patients, a short-acting IV drug with sedative or combined sedative and analgesic properties is mandatory.

Etomidate 0.3 mg/kg IV, a nonbarbiturate hypnotic, may be the preferred drug.

Fentanyl 5 mcg/kg IV (2 to 5 mcg/kg in children) also works well and causes no cardiovascular depression. NOTE: This dose is higher than the analgesic dose and needs to be reduced if used in combination with a sedative-hypnotic, eg, propofol or etomidate. Fentanyl is an opioid and thus has analgesic as well as sedative properties. However, at higher doses, chest wall rigidity may occur.

Ketamine 1 to 2 mg/kg IV is a dissociative anesthetic with cardiostimulatory properties. It is generally safe but may cause hallucinations or bizarre behavior on awakening. These adverse effects can be managed with low doses of prophylactic benzodiazepines.

Propofol, a sedative and amnesic, is commonly used in induction at doses of 1.5 to 3 mg/kg IV but can cause cardiovascular depression leading to hypotension.

Thiopental 3 to 4 mg/kg IV and methohexital 1 to 2 mg/kg IV tend to cause hypotension and are used less often.

Drugs to cause paralysis for intubation

Skeletal muscle relaxation with an IV neuromuscular blocker markedly facilitates intubation.

Succinylcholine (1.5 mg/kg IV, 2.0 mg/kg for infants), a depolarizing neuromuscular blocker, has the most rapid onset (30 seconds to 1 minute) and shortest duration (3 to 5 minutes). It should be avoided in patients with burns, muscle crush injuries > 1 to 2 days old, spinal cord injury, neuromuscular disease, renal failure, or possibly penetrating eye injury. About 1/15,000 children (and fewer adults) have a genetic susceptibility to malignant hyperthermia Malignant Hyperthermia Malignant hyperthermia is a life-threatening elevation in body temperature usually resulting from a hypermetabolic response to concurrent use of a depolarizing muscle relaxant and a potent,... read more due to succinylcholine. Succinylcholine should always be given with atropine in children because pronounced bradycardia may occur.

Alternative nondepolarizing neuromuscular blockers have longer duration of action (> 30 minutes) but also have slower onset unless used in high doses that prolong paralysis significantly. Drugs include atracurium 0.5 mg/kg, mivacurium 0.15 mg/kg, rocuronium 1.0 mg/kg, and vecuronium 0.1 to 0.2 mg/kg injected over 60 seconds.

Topical anesthesia for intubation

Intubation of an awake patient (typically not done in children) requires anesthesia of the nose and pharynx. A commercial aerosol preparation of benzocaine, tetracaine, butyl aminobenzoate (butamben), and benzalkonium is commonly used. Alternatively, 4% lidocaine can be nebulized and inhaled via face mask. Caution is needed when benzocaine is used because it can cause methemoglobinemia.

Post-intubation sedation and analgesia

Appropriate medications should also be immediately available for post-intubation sedation and analgesia. Combinations of opioids and benzodiazepines (eg, fentanyl and midazolam) can be quickly administered as bolus doses. Continuous infusion of sedatives such as propofol or dexmedetomidine can also be used. After initial intubation and resuscitation, clinical practice guidelines recommend the use of light sedation (rather than deep sedation) in adult critically ill patients and recommend the use of propofol or dexmedetomidine over benzodiazepines. Benzodiazepines have a higher incidence of delirium (3 General references Pulseless and apneic or severely obtunded patients can (and should) be intubated without pharmacologic assistance. Other patients are given sedating and paralytic drugs to minimize discomfort... read more ).

General references

  • 1. Higgs A, McGrath BA, Goddard C, et al: Guidelines for the management of tracheal intubation in critically ill adults. Br J Anaesth 120:323–352, 2018. doi: 10.1016/j.bja.2017.10.021

  • 2. Mosier JM, Hypes CD, Sakles JC: Understanding preoxygenation and apneic oxygenation during intubation in the critically ill. Intensive Care Med 43(2):226–228, 2017. doi: 10.1007/s00134-016-4426-0

  • 3. Devlin JW, Skrobik Y, Gélinas C, et al: Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU. Crit Care Med 46(9):e825-e873, 2018. doi:10.1097/CCM.0000000000003299

Drugs Mentioned In This Article

Drug Name Select Trade
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, AsperFlex, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidocan II, DermacinRx Lidocan III, DermacinRx Lidogel, DermacinRx Lidorex, DermacinRx Lidotral, DERMALID, Dologesic, Ela-Max, GEN7T, Glydo, Gold Bond, Icy Hot , LidaFlex, LidaMantle, Lido King Maximum Strength, Lidocan, LIDOCANNA, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , LidoLite, Lidomar , Lidomark, Lidopin, LidoPure, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, Lidtopic, Lidtopic Max, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lubricaine, Lubricaine For Her, Lydexa, MENTHO-CAINE , Moxicaine, Numbonex, Professional DNA Collection Kit, Proxivol, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Regenecare HA, Salonpas Lidocaine, Senatec, Solarcaine, SOLUPAK, SUN BURNT PLUS, Suvicort, Topicaine, Tranzarel, VacuStim Silver, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, ZiloVal, Zingo, Zionodi, ZTlido
ABSTRAL, Actiq, Duragesic, Fentora, IONSYS, Lazanda, Onsolis, Sublimaze, SUBSYS
Atreza, Atropine Care , Atropisol , Isopto Atropine, Ocu-Tropine, Sal-Tropine
Anectine, Quelicin
Diprivan, Fresenius Propoven
Advocate Pain Relief Stick, Americaine, Anbesol, Anbesol Baby , Anbesol Jr , Banadyne-3, Benzodent, Benz-O-Sthetic, Boil-Ease, Cepacol Sensations, Chloraseptic, Comfort Caine , Dry Socket Remedy, Freez Eez, HURRICAINE, HURRICAINE ONE, Little Remedies for Teethers, Monistat Care, Orabase, OraCoat CankerMelts, Orajel, Orajel Baby, Orajel Denture Plus, Orajel Maximum Strength, Orajel P.M., Orajel Protective, Orajel Severe Pain, Orajel Swabs, Orajel Ultra, Oral Pain Relief , Oticaine , Otocain, Outgro, Pinnacaine, Pro-Caine, RE Benzotic, Topex, Topicale Xtra, Zilactin-B
AK-T Caine, Pontocaine, Pontocaine in Dextrose, Pontocaine Niphanoid, Tetcaine, TetraVisc, TetraVisc Forte, Viractin
Nayzilam, Versed, Versed Syrup
IGALMI, Precedex
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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