Spinal cord compression following excision of posterior mediastinal tumor - Anesthesia concerns of a rare complication

Sir,

Spinal cord compression following thoracotomy for posterior mediastinal mass is a rare occurrence. Common causes such as hematoma, thrombosis of anterior spinal artery, and migration of hemostatic agents have been reported in literature. We report a case of posterior mediastinal mass who developed paraparesis after its excision in the postoperative period.

A 28-year-old male, belonging to ASA 1 physical status, was posted for excision of posterior mediastinal mass. Chest X-ray showed a round globular mass on left side of the chest [Figure 1a]. Computed tomography scan revealed a mass of 6 × 4 cm fixed to the sixth and seventh ribs near costovertebral junction [Figure 1b]. On arrival to operation theater, all standard ASA monitors were attached and a combined spinal epidural was performed at L3–L4 level and intrathecal morphine 300 μg was given. General anesthesia was induced and maintained with desflurane in O₂. Left muscle sparing thoracotomy through fifth intercostal space was performed. Tumor was found adherent to the posterior fifth, sixth, and seventh ribs. Complete removal of the mass along with partial removal of ribs was done. Surgicel was placed between transverse process. Patient was hemodynamically stable throughout and was extubated and shifted to ICU for monitoring. He was moving both lower limbs and was pain free. After 3 h, patient started complaining of band like pain in abdomen and weakness of both lower limbs, which quickly progressed to complete motor weakness of both lower limbs along with complete loss of sensations below T₈ dermatome. Bilateral plantar reflexes and bowel and bladder control were absent. Neurology consultation immediately obtained. Magnetic resonance imaging (MRI) lumbosacral spine was done, which revealed fracture of D₆ pedicle and spinal hematoma causing spinal cord compression [Figure 1c]. Therefore, an emergency costotransversectomy of D₅, D₆ along with hemilaminectomy of D₆ vertebrae were done along with hematoma evacuation. Postoperatively the patient's motor power in lower limb improved gradually and patient was shifted to ward with power of 2/5 in both lower limbs. Since his motor power in lower limbs was not improving, we did MRI lumbosacral spine, which revealed myelomalacia due to spinal hematoma. Patient is presently receiving limb physiotherapy.

Figure 1.

(a) Chest X-ray showing mediastinal mass. (b) Computed tomography scan showing the posterior mediastinal mass. (c) Magnetic resonance imaging revealing hematoma at D_6-7

Postthoracotomy paraplegia is rare (0.08%) but catastrophic.[1] Perioperative management of posterior mediastinal tumor can be complicated with a rare and dreaded event, such as postthoracotomy paraplegia. Factors such as hematoma at the costovertebral angle, migration of oxidized cellulose into spinal canal, and thrombosis of anterior spinal artery can be implicated.[2,3] Bleeding at the costovertebral junction is particularly notorious and difficult to control. It may require the use of surgicel, bone wax, and electrocauterization. Since spinal canal is only a few millimeters from the intrathoracic opening of the intervertebral foramen, closure of the wound with rib approximation may force surgicel or bone wax into the adjacent foramen by causing compressive forces on it.[4]

Hemostatic agents swell to form a gelatinous mass and may later migrate through intervertebral foramen into the epidural space. Such experiences ought to alert the anesthetist for the possibility of spinal cord compression, because the epidural catheter can easily be incriminated without thorough evaluation. Use of bone wax or surgicel must be brought to the knowledge of the anesthesiologist and periodic neurological examination should be carried out. There is a need for a high level of suspicion for iatrogenic spinal cord injury and strict postoperative vigilance for early diagnosis of spinal cord compression to ensure early intervention for such cases.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.