Fiberoptic Intubation and Monitoring of Somatosensory Evoked Potentials in Children with Mucopolysaccharidoses

Priv.Doz. Dr.med. Hinnerk Wulf and Ulf Linstedt
Department of Anesthesiology and Intensive Care Medicine
Hospital of the Christian-Albrechts-University, Kiel
Schwanenweg 21, D 24105 Kiel, Germany

Phone: ++49 (0)431 597 2984/2991; Fax: ++49 (0)431 597 3002
email: wulf@anaesthesie.uni-kiel.de

The correct citation of this article for reference is:

Wulf H, Linstedt U: Fiberoptic Intubation and Monitoring of Somatosensory Evoked Potentials in Children with Mucopolysaccharidoses. The Internet Journal of Anesthesiology 1999; Vol3N1: http://www.ispub.com/journals/IJA/Vol3N1/mpssep.htm ; Published January 1, 1999; Last Updated January 1, 1999.

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Abstract

Background Information

Cases

Discussion

References

Key words: fibreoptic intubation; difficult airway; mucopolysaccharidoses; monitoring; neurologic complication; tetraparesis; somatosensory evoked potentials.

Abstract   (Back to Quick Links)

The management of children with mucopolysaccharidosis (MPS) is a challenge for the anesthesiologist, primarily because of difficult airways. Furthermore, certain types of MPS (I,VI, VII) are at risk for cervical spine compression. Therefore, we recommend monitoring of somatosensory potentials during intubation and during positioning of these patient for surgery. Two case reports are presented to demonstrate the perioperative management.

Background Information (Back to Quick Links)

Children with mucopolysaccharidosis (MPS) are a challenge for the anesthesiologist, especially since difficult airways are often associated with these hereditary lysosomal storage diseases. In addition, in some types of MPS there is a specific risk for compression of the cervical spinal cord (table 1). Therefore, our management of two children suffering from mucopolysaccharidosis is described with special emphasize on these two problems, difficult airway and compression of the spinal cord, respectively.

Table 1: Risk of cervical spinal cord compression in different types of MPS.

Cases (Back to Quick Links)

Case 1: A 12-year-old girl with MPS type VI (Maroteaux-Lamy) underwent a preoperative magnetic resonance imaging (MRI) showing a critical stenosis of the cervical spinal cord due to thickening of the dura and a hypoplastic dens axis, but was without clinical symptoms of spinal cord compression. She was scheduled for orofacial surgery to improve the instability of her jaw. Monitoring of somatosensory evoked potentials (SEP) was applied and fibreoptic guided intubation was achieved during sedation and spontaneous breathing. During intubation and the first hour of surgery SEP remained stable. Suddenly the cortical waves first decreased and than vanished and spinal cord compression was suggested. The operation was interrupted and the head was newly positioned. The cortical waves of the SEP reoccurred immediately. Surgery was completed without further complication and the girl showed no neurological deficits postoperatively (1).

Case 2: A 4-year-old boy with MPS type I (Hurler) presented for tonsillectomy and adenotomy because of recurrent upper airway infections, often complicated by airway obstruction. Preoperative magnetic resonance imaging showed abnormal thickening of the dura without critical stenosis of the cervical spinal cord. Again, a fibreoptic intubation was performed under slight sedation and spontaneous breathing. Assisted by SEP-monitoring the optimal position for surgery could be evaluated. Anesthesia and surgery was completed without problems and the neurological status was unaltered postoperatively.

Discussion (Back to Quick Links)

Difficult airway management is a well known risk factor of mucopolysaccharidosis.

Therefore, it is recommended to anticipate difficult airways in these patients and to use fibreoptic intubation as the method of choice. In a recent case report the management of two children with mucopolysaccharidosis MPS type I and VI, respectively, is described using fibreoptic intubation after placing a laryngeal mask (2). Nevertheless, difficult intubation serves not as the only reason to use fibreoptic intubation in these cases. Conventional laryngoscopy should be avoided because of the risk of cervical spinal cord compression while positioning the patient for (difficult) intubation. If the laryngeal mask airway is used as a device to assist fibreoptic intubation, one should rather refrain from extending the neck in order to introduce the laryngeal mask.

Some types of MPS are at special risk for compression of the cervical spinal cord (table 1). These are atlanto-axial dislocation in presence of a hypoplastic dens axis, and preexisting spinal cord compression due to abnormal thickening of the dura (3,4,5,6). Obviously there is an indication for monitoring intraoperatively the neural conduction in the cervical spinal cord during intubation and positioning of the patient for surgery. It is our current clinical practice to monitor somatosensory evoked potentials of the median nerve (SEP) routinely in patients at risk, as described above for anesthesia in children with mucopolysaccharidoses:

Due to the risk of severe permanent neurologic sequelae (tetraplegia) we consider the monitoring of SEP to be an essential contribution to the safety of anesthesia in patient with a type of MPS that is at specific risk (types I, IV, VI, VII, (table 1)(6,7)). Critical stenosis could be present without clinical symptoms. Therefore, in these types of MPS a preoperative MRI should be considered to evaluate the individual risk (5).

References (Back to Quick Links)

1. Linstedt U, Maier Ch, Jöhnk H, Stephani U: Threatening spinal cord compression during anesthesia in a child with mucopolysaccharidosis VI. Anesthesiology 1994; 80: 227-229. (Back to text)

2. Walker RWM, Allen DL, Rothera MR: A fibreoptic intubation technique for children with mucopolysaccharidoses using the laryngeal mask airway. Paediatric Anaesth 1997; 7: 421-426. (Back to text)

3. Beighton P, Craig J: Atlanto-axial subluxation in the Morquio syndrome. Report of a case. J Bone Joint Surg 1973; 55: 478-481. (Back to text)

4. Sostrin RD, Hasso AN, Peterson DI, Thompson JR: Myelographic features of mucopolysaccharidoses: a new sign. Radiology 1977; 125: 421-424. (Back to text)

5. Kulkarni MV, Williams JC, Yeakley JW: Magnetic resonance imaging in the diagnosis of the cranio-cervical manifestations of the mucopolysaccharidoses. Magn Reson Imaging 1987; 5: 317-323. (Back to text)

6. Diaz JH, Belani KG: Perioperative management of children with mucopolysaccharidoses. Anesth Analg 1993; 77: 1261-1270. (Back to text)

7. Walker RWM, Darowski M, Morris P, Wraith JE: Anaesthesia and mucopolysaccharidoses. Anaesthesia 1994; 49: 1078-1984. (Back to text)

Address for correspondence:

Priv.Doz. Dr.med. Hinnerk WULF
Department of Anesthesiology and Intensive Care Medicine
Hospital of the Christian-Albrechts-University, Kiel
Schwanenweg 21
D 24105 Kiel, Germany
Phone: ++49 (0)431 597 2984/2991; Fax: ++49 (0)431 597 3002
email: wulf@anaesthesie.uni-kiel.de

© Internet Scientific Publications, L.L.C., 1996 to 1999.

First Published: October 1996

The Internet Journal of Anesthesiology