EMERGENCY MANAGMENT OF A DIFFICULT AIRWAY IN AN INFANT WITH ARTHROGRYPOSIS MULTIPLEX CONGENITA

A 4 month old infant with arthropgryposis multiplex congenital was admitted to the paediatric assessment unit. The infant had been acutely unwell over the preceding 12 hours with respiratory compromise and a productive cough with green sputum. He had signs of respiratory distress with a RR of 40, pulse oximetry showed SpO2 of 85% on air and only 90% with a facemask, reservoir bag and high flow oxygen. It was felt that the infant would need to be intubated and ventilated. Two months before the infant had had a respiratory arrest on the neonatal ward and was unable to be intubated. That situation was resolved by mask ventilation and rescue with an LMA. There were obvious concerns that direct laryngoscopy would be unsuccessful and may precipitate a terminal decline in the patient’s condition.

The infant’s breathing was supported by bag/mask ventilation whilst he was transferred to an ENT theatre. Further anaesthetic support and an ENT surgeon were sought. I.v. access was established through a scalp vein. Ventilation was switched to an Ayres T piece with Jackson-Rees modification. Induction of anaesthesia was initiated with sevoflurane and oxygen. Direct laryngoscopy showed a Lehane and Cormack grade 4 view.

A rigid bronchoscope with video camera monitor was used by the ENT surgeon to obtain a view of the glottis. An epidural catheter was placed down the side port of the bronchoscope and was directed through the vocal cords. The bronchoscope was removed and a fine bore suction catheter was railroaded over the epidural catheter to give more stiffness. The positions of the end of the catheters were checked with the bronchoscope. A size 3.0cm uncuffed endotracheal tube was then railroaded over the catheters into trachea. Position and length were confirmed with the bronchoscope and ventilation was continued. The arrangement is shown in Figure 1.

The child was then transferred to the adult ICU where a retrieval team arrived to transfer the patient to a PICU.

What is arthrogryposis? Describe some methods for achieving control of the difficult paediatric airway.

James Day

Arthrogryposis, also known as arthrogryposis multiplex congenital is a rare congenital disorder that comprises a variety of conditions characterised by multiple contractures found at birth. It is a non progressive disease. The disease derives its name from Greek; literally meaning ‘curved or hooked joints’. The condition occurs in 1/3000 live births. Prognosis depends on the underlying cause, most having a normal lifespan. If there is CNS involvement in addition then about 50% die in the first year.

The major cause of arthrogryposis is foetal akinesis due to foetal abnormalities or maternal disorders. During early embryogenesis, joint development is almost always normal. Motion is essential for the normal development of joints and their adjoining structures. Lack of foetal movement causes extra connective tissue to develop around the joint. This results in fixation of the joint, limiting movement and further aggravating the joint contracture.

Features include joint rigidity and dislocations. There is limitation of joint movement with fixation in typical postures due to shortening of the flexor muscles. Patients are classically described as being like a “thin wooden doll” due to the decreased muscle mass and deficient subcutaneous tissue. Although most contractures affect the extremities, the face can be involved too. The range of motion of the jaw can be significantly limited due to temperomandibular joint involvement and microstomia (1, 2). Other facial deformities include asymmetry, flat nasal bridge, haemangioma, micrognathia, cleft palate and trismus. Other respiratory issues include tracheal and laryngeal clefts and stenosis. Scoliosis, hypoplastic respiratory muscles and diaphragm may compromise respiratory function.

Patients may also be more sensitive to the respiratory depressant effects of intravenous and inhalational anesthetics agents (1,4). Respiratory problems may be related to associated myopathy, pulmonary hypoplasia and spine deformities (3,4). Baines et al. (10) reviewed 396 anaesthetic agents in 67 patients with AMC and found no episodes malignant hyperthermia with exposure to known triggering agents. Choice of neuromuscular blocking agent is important as patients with an underlying myopathic disorder are at risk of an exaggerated hyperkalaemic response.

Martin et al. (3) found a 25% incidence of maxillofacial involvement with limited mouth opening in 3 of the 12 patients. Steinberg et al. reviewed 23 patients and found maxillofacial involvement in 22% and 3 of the 23 patients had limited mouth opening. The limited mouth opening can be so severe as to make direct laryngoscope impossible (1,2,4,5).

Most of the techniques described in the literature for management of the difficult paediatric airways involve elective cases where there is time for preoperative assessment of the airway and preparation of various equipment. The following are various ways to achieve airway control.

There have been 2 case reports of using a flexible 2.2mm fibreoptic bronchhoscope with a preloaded 3.0mm ETT passed through a an LMA (6). In one case the LMA and ETT were left both in place; in the other case the LMA was removed by using a size smaller tube as an extension as a modification of Ullman’s technique (7).

Ravishankar et al. (8) described the use of a 70o lateral illuminating nasendoscope used orally to visualise the glottis and allow passage of a ETT loaded with a stylet and bent into a J shape. They described this technique in two cases, one 8kg and the other 10kg. The benefits of a rigid scope are better resolution than the end on flexible fibreoptic scope. As the size is reduced for paediatric use there is a reduction in the number of optical fibres compromising resolution and image size (9).

Other techniques such as use of retrograde intubation, lightwands, needle cricothyroidotomy, tracheostomy are described. Use of a gum elastic bougie to facilitate blind nasotracheal intubation in children has been reported in 3 cases of temporomandibular joint ankylosis where there was no mouth opening. It must be remembered that the fall back rescue techniques in such patients may prove to be very difficult to perform given neck shortening and contractures. In the emergency setting patients are not pre-medicated with anti-cholinergics and anti- sialogues.

Lessons Learnt

Management of a difficult paediatric airway remains a problem and challenge for anaesthetists and intensive care physicians. There is a lot written in the literature about planned airway procedures for elective operations but these may not always be utilised in the emergency case where the patient is acutely unwell.

In the district general hospital advanced paediatric skills are becoming diluted. These patients will attend their local hospital in the emergency setting but will likely attend a regional centre for elective procedures further diluting the skill base in the local hospital.

References

1. Epstein JB, Wittenberg GJ. Maxillofacial manifestations and management of arthrogryposis : literature review and case report. J Oral Maxillofac Surgery 1987; 45: 274-279.
2. Steinberg B, Nelson VS, Feinberg SE et al. Incidence of maxillofacial involvement in arthrogryposis multiplex congenital. J Oral Maxillofacial Surgery 1996; 54: 956-959.
3. Martin S, Tobias JD. Peroperative care of the child with arthrogryposis. Paediatr Anaesth 2006; 16: 31-37.
4. Oberoi GS, Kaul HL, Gill IS et al. Anaesthesia in arthrogryposis multiplex congenital: case report. Can J Anaesth 1987; 34: 288-90.
5. Thomas JA, Chiu-Yeh M, Moriconi ES. Maxillofacial implications and surgical treatment of arthrogryposis multiplex congenital. Compend contin Educ Dent 2001; 22: 588-592.
6. Nguyen NH, Morvant EM, Mayhew JF. Anesthetic management for patients with arthrogryposis multiplex congenital and severe micrognathia: case reports. Journal Clinical Anesthesia 2000; 12: 227-30.
7. Ullman DA. Laryngeal mask airway and the ASA difficult airway algorithm [Letter]. Anesthesiology 1996; 85: 685-8.
8. Ravishankar M, Kundra P, Agrawal K, Kutralam NS, Arun N, Vijaykumar OP. Rigid nasendoscope with video camera system for intubation in infants with Pierre-Robin sequence. British Journal of Anaesthesia 2001; 87: 728-31.
9. Ovassapian A. Fiberoptic Airway Endoscopy in Anesthesia and Critical Care, 1st Edn. New York: Raven Press. 1990; 6-8.
10. Baines DB, Douglas ID, Overton JH. Anaesthesia for patients with arthrogryposis multiplex congenital: what is the risk of malignant hyperthermia? Anaesth Intensive Care 1986; 14: 370-72