Muscle Relaxants Facilitate Intubation in Bilateral Mandibular Condylar Fractures
Yes, muscle relaxants are strongly recommended to facilitate tracheal intubation in patients with bilateral mandibular condylar fractures, as they reduce poor intubating conditions from 24.6% to 4.1% and decrease pharyngeal and laryngeal injury from 18.7-22.6% to 9.7%. 1, 2, 3
Primary Recommendation
The use of a muscle relaxant is recommended to facilitate tracheal intubation (GRADE 1+ recommendation with STRONG AGREEMENT). 1 This applies universally to all patients requiring tracheal intubation, including those with mandibular fractures where anatomical distortion already complicates airway management.
Muscle relaxants specifically reduce the incidence of pharyngeal and laryngeal injuries during intubation from 18.7-22.6% down to 9.7%, which is particularly critical in trauma patients with mandibular fractures who already have compromised airway anatomy. 2, 3
Clinical Rationale for Mandibular Fracture Cases
In bilateral mandibular condylar fractures, the mandible loses its normal structural support, making mouth opening and jaw manipulation during laryngoscopy more difficult and potentially more traumatic. 4
Without muscle relaxation, intubation difficulty increases significantly (12% vs 1% difficult intubation rate), and this baseline difficulty would be compounded by the anatomical distortion from bilateral condylar fractures. 5
Post-intubation upper airway symptoms occur more frequently without muscle relaxants (57% at 2 hours vs 43% with relaxants), which is particularly problematic in patients with pre-existing mandibular trauma. 5
Specific Agent Selection
For patients with bilateral mandibular condylar fractures requiring intubation:
Succinylcholine 1.0-1.5 mg/kg IV (70-105 mg for a 70 kg patient) is first-line when no contraindications exist, providing the fastest onset (approximately 1 minute) for rapid-sequence intubation. 6, 7
Rocuronium 1.0-1.2 mg/kg IV (70-84 mg for a 70 kg patient) is the alternative when succinylcholine is contraindicated, though it has a slightly lower first-pass success rate (74.6% vs 79.4%). 6, 7
Cisatracurium is an excellent option for patients with renal or hepatic dysfunction due to organ-independent Hofmann elimination, requiring no dose adjustment. 2
Critical Safety Considerations
The sedative-hypnotic agent (etomidate 0.2-0.4 mg/kg or ketamine 1-2 mg/kg) MUST be administered before the neuromuscular blocking agent to prevent awareness during paralysis, with awareness occurring in 2.6% of emergency intubations when this sequence is violated. 6
Etomidate provides superior hemodynamic stability compared to other induction agents, which is important in trauma patients who may have concurrent injuries. 6
Fentanyl 1-2 mcg/kg IV (70-140 mcg for a 70 kg patient) should be administered prior to induction for analgesia. 6
Alternative Approach (Not Recommended as First-Line)
While awake nasotracheal intubation with bilateral superior laryngeal nerve block has been described for mandibular fractures, this technique is more complex and does not provide the optimal intubating conditions that muscle relaxants offer. 4
Relaxant-free intubation can achieve clinically acceptable conditions in 98.4% of routine cases, but excellent conditions occur significantly less frequently (72% vs 87% with relaxants), and this margin of safety is unacceptable in already-difficult airways. 8
Common Pitfalls to Avoid
Do not attempt intubation without muscle relaxants in mandibular fracture patients based on the misconception that relaxants are optional for short procedures—the anatomical distortion from bilateral condylar fractures already creates a difficult airway that requires optimal conditions. 1, 5
Avoid using inadequate doses of muscle relaxants (below 2× ED95), as subtherapeutic dosing negates the benefits while still exposing patients to side effects. 1
Do not use succinylcholine if the patient has hyperkalemia risk, malignant hyperthermia history, known myopathy, immobilization >3 days, burns, crush injuries, or spinal cord injuries. 6
Ensure sugammadex (if using rocuronium) and dantrolene (if using succinylcholine) are immediately available for emergency reversal or complications. 6