Evaluating Atlantoaxial Instability in Down Syndrome Patients Before Intubation

Initial Assessment

The American Society of Anesthesiologists recommends reviewing a patient's medical records for history of atlantoaxial instability, previous difficult intubation, or neurological symptoms suggesting cervical spine pathology in Down syndrome patients requiring intubation 1, 2
Assess for clinical signs of atlantoaxial instability including neck pain, torticollis, gait abnormalities, or neurological deficits in Down syndrome patients 1, 2
Evaluate facial and jaw features, including mouth opening, ability to prognath, head and neck mobility, and presence of prominent upper incisors in Down syndrome patients 1
Measure anatomical landmarks including Mallampati score, thyromental distance, sternomental distance, and interincisor distance in Down syndrome patients 1, 2

Obtain cervical spine radiographs with flexion-extension views to measure the atlantodens interval (ADI) - an ADI >4-5mm indicates instability in Down syndrome patients 2
Consider advanced imaging such as CT or MRI if radiographs are inconclusive or if neurological symptoms are present in Down syndrome patients 2
When available, use virtual laryngoscopy/bronchoscopy or three-dimensional printing to further characterize the airway anatomy in Down syndrome patients 1, 2

Have a preformulated strategy for management of the anticipated difficult airway, considering the patient's condition and risk of atlantoaxial instability in Down syndrome patients 2, 3
Ensure that a skilled assistant is present or immediately available to help with airway management and cervical spine stabilization in Down syndrome patients 2, 4
Prepare equipment for both routine and difficult airway management, including video laryngoscopy and flexible bronchoscopy in Down syndrome patients 2, 3

Consider awake intubation if the patient is cooperative and has significant atlantoaxial instability in Down syndrome patients 3, 5
For patients requiring general anesthesia, maintain neutral head position throughout induction and intubation in Down syndrome patients 6, 7
Apply manual in-line stabilization of the cervical spine during laryngoscopy to minimize neck movement in Down syndrome patients 7, 8
Use video laryngoscopy as the primary approach to minimize cervical spine movement during intubation in Down syndrome patients 2, 9
Limit the number of intubation attempts to avoid potential injury to the cervical spine in Down syndrome patients 3, 8

Confirm proper tube placement with continuous waveform capnography in Down syndrome patients 6, 8
Secure the endotracheal tube carefully to prevent tube movement that could disturb the cervical spine in Down syndrome patients 6, 7
Maintain neutral head position after intubation; avoid neck flexion which may push the tube further into the airway, and extension which may pull the tube out in Down syndrome patients 6, 7

Document the airway assessment findings, intubation technique used, and any difficulties encountered in Down syndrome patients 4, 5
Consider instructing the patient or family to register with an emergency notification service regarding the atlantoaxial instability in Down syndrome patients 4

Failure to recognize atlantoaxial instability before airway manipulation can lead to catastrophic neurological injury in Down syndrome patients 2, 3
Multiple assessment tools should be used in combination for better prediction of difficult airway in Down syndrome patients 1
Case reports have identified difficult laryngoscopy and intubation in patients with Down syndrome, highlighting the importance of thorough preparation 1, 2