Abscess of the medulla oblongata following endotracheal intubation

A 71 year old man was admitted for a myocardial infarction following which he was successfully resuscitated for a cardiac arrest secondary to ventricular fibrillation. He was intubated and ventilated in the peri‐arrest period. After extubation, he complained of neck pain and dysphagia. A flexible laryngoscopy examination revealed an oedematous left larynx. He was subsequently lost to follow up. His symptoms worsened over the next 2 months. He lost 15 kg in weight and suffered fevers and night sweats.

On readmission, he was cachectic. He had discomfort on moving his neck. He had a chest wall abscess and a hard lymph node attached to the left trapezius muscle. Magnetic resonance imaging (MRI) of the neck revealed a large retropharyngeal abscess with osteomyelitis of the C1 and C2 vertebrae. Aspiration of the chest wall abscess revealed methicillin resistant Staphylococcus aureus. Intravenous vancomycin and metronidazole were commenced and the neck was stabilised with a hard collar.

One week later, he complained of acute onset severe neck pain. He developed bulbar palsy and right sided weakness. MRI revealed an abscess in the posterior part of the medulla in continuity with the retropharyngeal collection (fig 1A) and multiple lung abscesses. He required a tracheostomy and positive pressure ventilation. It was felt that surgical aspiration of the medulla abscess would be too risky, thus a halo traction brace was applied and conservative management with antibiotics was adopted.

Figure 1 Post‐gadolinium T1 weighted magnetic resonance imaging of the brainstem and cervical spinal cord. (A) One week post admission, showing the development of a medullar abscess in continuity with the retropharyngeal collection and C1/2 osteomyelitis; (B) 6 months later after prolonged antibiotic therapy demonstrating near resolution.

He was weaned off the ventilator and the halo traction was replaced by a hard collar. It was not possible to wean him from his tracheostomy, because of a residual left sided bulbar palsy. He also required permanent gastrostomy feeding. His right hemiparesis improved, although he was left wheelchair bound. Repeat MRI 6 months after admission showed near resolution of the medulla abscess (Fig 1B). Antibiotics were continued for 10 months. The patient was discharged to a nursing home 8 months after admission and has shown continuing physical improvement in outpatient follow up.

Retropharyngeal abscesses are a rare but recognised complication of intubation.¹ They usually occur following foreign body ingestion (usually fish or chicken bones), pharyngotonsillitis, peritonsillar abscesses and dental infections.² They can cause great morbidity. Reported complications include airway obstruction, mediastinitis, empyema, septicaemia, osteomyelitis, and epidural abscesses.²,³,⁴ To our knowledge, this is the first case reported of an intraparenchymal brainstem abscess occurring as a complication of a retropharyngeal abscess.

Brainstem abscesses may arise spontaneously, or from haematogenous or contiguous spread, usually from the ears.⁵ Case mortality is thought to be high, but reports in the literature have, like this one, mainly been of single cases that have had a successful outcome. There is no consensus over management. Options include open surgical drainage, stereotactic aspiration, and medical management with antibiotics alone.⁵ Conservative management may be useful where the causative organism is known and/or the lesion would present too great a surgical risk, as in this case. Operative intervention is useful for identifying the causative organism, for decompressing large lesions, and when the patient is deteriorating despite antibiotic therapy.⁵ The duration of antibiotic treatment is to an extent empirical. In previous reports of brainstem abscesses treated with antibiotics, the treatment was usually continued for 6–8 weeks. In our case, antibiotics were continued for 10 months because of the coexistent cervical osteomyelitis.

This case illustrates a devastating complication arising from endotrachracheal intubation and the possibility of conservative management in the management of medulla abscesses owing to the obvious risks of surgical intervention.