Difficult airway in a pediatric case of pycodysostosis.

Pycodysostosis is a genetic autosomal rare disease with an incidence of 1:1.7 million births; the pathophysiology of the disease is related to mutation of cathepsin K gene. Sleep apnea, respiratory difficulties because of chest and oral abnormalities may cause a challenge to the anesthetist during intubation and/or mechanical ventilation. In this case report we will discuss a case of pycodysostosis with a difficult airway.

INTRODUCTION

Pycodysostosis is a genetic autosomal rare disease with an incidence of 1:1.7 million births, the pathophysiology of the disease is related to mutation of cathepsin K gene[1] leading to osteoclast cells dysfunction and consequently osteosclerosis.[12]

The patient characterized by being a short stature, increased bone density with fragile bone and frequent fractures, short and stubby fingers, and craniofacial abnormalities caused by delayed suture closure.[3]

Sleep apnoea, respiratory difficulties because of chest and oral abnormalities may cause a challenge to the anesthetist during intubation and/or mechanical ventilation.[4]

In this case report we will discuss a case of pycodysostosis with a difficult airway.

CASE REPORT

A 5-year-old boy with a good mentality had a fracture of his left femur scheduled to do plate in the left femur in the prince sultan military medical city, the patient known to have pycodysostosis.

The patient was underweight to his age (12 kg), had a blue sclera and short stature for his age (101 cm), frontal bushing, micrognathia, Mallampati grade II, prominent nose, and osteosclerosis and chest deformities in the form of pectusexcavatum [Figures 1–3].

Figure 1

Skull X-ray

Figure 3

Pectus excavatum of the chest, upper view

Inhalational induction and chest pectus excavatun

There is also a history of delayed sagittal stenosis, craniosynostosis involving the superior sagittal, which was corrected surgically at age of 2 years.

Furthermore, the patient had a history of gastro esophageal reflux, sleep apnea syndrome and trachiomalacia with an improving course.

There was history of anesthesia 1-week before where a laryngeal mask was tried first but with no satisfactory ventilation and the patient experienced severe desaturation and bradycardia, resuscitation was done, patient was awaken, shifted to the Intensive Care Unit (ICU) and the surgery was postponed.

The labs were normal; imaging regarding the cervical skeleton was also unremarkable.

Regarding his family history; there was a parental consanguinity and pycodysostosis in his both brothers.

The parents were clearly notified and agreed to sign about the case of their child, the risk possibility, the method of anesthesia and its complications, a pediatric ICU bed was ready.

In the operating room there was no previous premedication or an intravenous access, full routine monitoring was connected.

The anesthesia started by an inhalational technique using sevoflurane and 100% O2, there was good ventilation, and intravenous access was inserted and secured.

0.15 mg/kg of cisatracurium, fentanyl 3 μg/kg, dexameshtasone 0.15 mg/kg and granistron 40 μg/kg were given and intubation was tried 2 times using different blades sizes of Macintosh laryngoscope with an impossible intubation, the view was Cormack and Lehane grade IV, rapidly the patient airway was suctioned and ventilated, then Glidescope® blade size 2 was used and it facilitated the view greatly, endotrachial tube size 4.5 was inserted, checked, confirmed, secured and lung mechanically ventilated.

The glidescope showed a left and up deviation of the laryngeal opening but with normal anatomy [Figures 4 and 5].

Figure 4

The up and to the left larynx

Figure 5

Postextubation under vision of the glidescope

Anesthesia was maintained with sevoflurane, oxygen, and air and accompanied by caudal block that was easy.

DISCUSSION

Pycodysostosis is a very rare autosomal disease with the incidence of 1:1.7 million births with male:Female ratio 2:1.

This syndrome characterized by genetic defect located on chromosome 1q21 with a sequel of changes in a lysosomal cystine protease, cathepsin K.

The end result is: Short stature, increase in bone density, fractures, stubby hands and feet with osteolysis of the distal phalanges, dysplastic nails, clavicular dysplasia, congenital pseudarthrosis of the clavicle, spondylolysis, frontal and parietal bossing, beaked nose, prominent eyes with bluish sclera, hypoplasia of the maxilla and mandible, open fontanels and sutures, craniosynostosis, nonpneumatized paranasal sinuses, obtuse mandibular angle, grooved palate and Arnold–Chiari malformation.[35]

The above features make the people with this syndrome with potential difficult airway, which we already faced in this case.

Because of the rarity of this syndrome, very few cases reported with the fewer concern to anesthesia.[4678]

All the previous reports did not show a difficulty in the airway although all the features were presented.

In the previous literature no age or race was spared, the youngest diagnosed case was 9 months old but our case was diagnosed later on in age of 15 months.[4]

The new finding in this case is the trachiomalacia, pectus excavatum and the abnormal anterior and lateral shift of the larynx, which made the ventilation by the laryngeal mask impossible and the intubation by the conventional methods extremely difficult.

The conclusion is that the pycodysostosis can be associated with abnormal airway anatomy and difficult ventilation or even intubation, another thing is the great help of the Glidescope®.