of patients with mucopolysaccharidosis

Stabilize my neck

  • MPS patients are at a high risk of cervical cord injury, which may result in paralysis and sudden, premature death
  • They may experience atlantoaxial instability,1–4 commonly associated with cervical cord compression and myelopathy
  • Use manual in-line stabilisation to prevent cervical spine injury5
  • Limit the degree of flexion/extension because of the possible laxity of ligaments (with or without odontoid dysplasia) and cervical stenosis
  • Intubation: maintain the patient in a neutral position during intubation since the “sniff” position may not be possible. Use fibre-optic intubation or video laryngoscopy5
  • Maintain the rest of the spinal column in the neutral position, as compression may occur in other regions
  • Neurophysiological monitoring is recommended for all patients undergoing prolonged procedures (more than 30 minutes) or all procedures involving a spine or manipulation of the head (oral surgery, etc) surgeries

HIGH RISK ANAESTHESIA (both intubation and extubation)

  • Respiratory failure and airway–related emergencies are a common cause of morbidity in MPS patients,5 especially during surgical interventions.6 Critical decreases in oxygen saturation may occur suddenly
  • In an airway anaesthesia emergency, there may be less than 3–5 minutes to perform an emergency tracheostomy before permanent brain damage occurs
  • ANY sedative can cause respiratory complications, severe hypoxaemia, and, consequently, neurological impairment
  • Airway obstruction:
    • MPS patients may have obstructive sleep apnoea (OSA), increasing the risk of airway emergencies and chronic hypoxaemia
    • Airway obstructions (see video) may cause diffculties with mask ventilation and intubation
    • Temporomandibular joint contracture with diffculty opening the mouth, and accumulation of glycosaminoglycans (GAGs) in the tongue, oral pharynx, and larynx can impede access to the upper airway and identification of the glottis. This may result in negative pressure pulmonary oedema, or an inability to ventilate/intubate5 or visualise the airway7
    • Serious complications may occur during extubation, including pulmonary oedema, and the need for re–intubation or emergency tracheostomy
  • Have an otolaryngologist (ENT), preferably with MPS experience, readily available during any surgical procedure on MPS patients due to the high potential for an emergency tracheostomy5
  • Ensure the ENT is aware that performing an emergency tracheostomy is more diffcult, has a higher risk and will take longer for a patient with MPS because of their shorter neck, thickened soft tissue, and the depth of their trachea5
  • Be prepared for alternative methods of intubation (e.g. fibre–optic intubation) if mask induction followed by oral tracheal intubation is unsuccessful5
  • An oral anxiolytic may reduce anxiety and increase the potential for successful fibre–optic intubation – but, if the patient falls asleep, he or she may desaturate to dangerous levels due to upper airway obstruction
  • Have the pre–op nurse closely monitor oxygen saturation and call the anaesthesia team immediately if changes in oxygen saturation occur
  • Provide supplemental O2 during intubation due to the potential for diffculty in ventilation and oxygenation
  • Consider use of nitrous oxide to assist in placement of an intravenous catheter, followed by induction with midazolam or fentanyl (reversed by flumazenil and naloxone, if required)5
  • Consider placing the patient in the lateral position during induction phase if this improves their airway
  • Use fibre–optic bronchoscopy for tracheal induction if patient has a diffcult airway5
  • Use of a laryngeal mask airway (LMA) or nasal airway has been found to improve ventilation during bronchoscopy5
  • Consider inserting a J–tipped guide–wire through the suction channel of the bronchoscope into the trachea, remove the bronchoscope and insert a ureteral dilator or airway exchange catheter over the wire, then advancing the endotracheal tube (ETT) over this to help guide it into the trachea5
  • Avoid use of muscle relaxants until endotracheal intubation is achieved5
  • Use an ETT that is 2–3 times smaller than expected based on age8
  • In order to increase oxygen delivery to the patient during fibre–optic bronchoscopy, consider advancing a short ETT into the contralateral nares to provide continuous O2 into hypopharynx. Also, attach O2 to the suction port of the bronchoscope and intermittently inject O2 from tip of fibre
  • Ensure full reversal of the muscle relaxant and place a nasopharyngeal airway prior to extubation5
  • Perform extubation in an area with access to the full medical personnel required should the patient need immediate re–intubation or an emergency tracheostomy5


  • Diffcult intubations may result in injury to the glottis, stridor, infection or airway collapse
  • Potential for chronic hypoxaemia due to obstructive sleep apnoea (OSA)
  • Once MPS patients are extubated, re–intubation may not be possible, creating a potential emergency
  • Video of anaesthesia techniques
  • If injury to the glottis has occurred, consider delaying extubation
  • Do not extubate until the airway is confirmed to be clear
  • Always have an experienced otolaryngologist (ENT) or paediatric surgeon in the room during all surgical procedures on MPS patients due to the high potential for an emergency tracheostomy


  • Significant cardiac manifestations are reported for MPS patients9,10
  • Cardiac valve disease is the most commonly reported cardiac manifestation in MPS patients,5,9,10 increasing the risk of mortality during surgical procedures5
  • Irreversible ischaemia and cardiac arrest due to hypotension may occur
  • Continuously monitor MPS patients with electrocardiography to identify conduction abnormalities and signs of myocardial ischaemia
  • Perform an echocardiogram to identify cardiac valve regurgitation or stenosis, as well as decreased function
  • Monitor blood pressure using intra–arterial cannulae if surgery is lengthy or high risk5