Anaesthetic considerations in posterior instrumentation of scoliosis due to spinal muscular atrophy: Case series of 56 operated patients

Profound hypoxemia and hypotension during posterior spinal fusion in a spinal muscular atrophy child with severe scoliosis: a case report

BACKGROUND

Anesthesia for spinal muscular atrophy (SMA) patients undergoing spinal deformity surgery is challenging. We report an unusual case of an SMA girl who developed severe intraoperative hypoxemia and hypotension during posterior spinal fusion related with surgical positioning.

CASE PRESENTATION

A 13-yr-old girl diagnosed with SMA type 2, severe kyphoscoliosis and thoracic deformity was scheduled for elective posterior spinal fusion. She developed severe hypoxemia and profound hypotension intraoperatively in the prone position with surgical table tilted 45° to the right. Though transesophageal echocardiography (TEE) could not be performed due to limited mouth opening, her preoperative computed tomography revealed a severely distorted thoracic cavity with much reduced volume of the right side. A reasonable explanation was when the surgeons performed surgical procedure with the tilted surgical table, the pressure was directly put on the shortest diameter of the significantly deformed thoracic cavity, causing severe compression of the pulmonary artery, resulting in both hypoxemia and hypotension. The patient stabilized when the surgical table was tilted back and successfully went through the surgery in the leveled prone position.

CONCLUSIONS

Spinal fusion surgery is beneficial for SMA patients in preventing scoliosis progression and improving ventilation. However, severe scoliosis and thoracic deformities put them at risk of both hemodynamic and respiratory instability during surgical positioning. When advanced monitoring like TEE is not practical intraoperatively, preoperative imaging may help with differential diagnosis, and guide the surgical positioning to minimize mechanical compression of the thoracic cavity, thereby helping the patient complete the surgery safely.

Clinical characteristics and anaesthetic management of severe scoliosis patients with spinal muscular atrophy: case series

Introduction and importance

There is no expert consensus or guidance on perioperative anaesthesia management for spinal surgery of spinal muscular atrophy (SMA) patients with severe scoliosis (Cobb≧90°). We provide a comprehensive summary of the perioperative characteristics observed in patients with SMA and propose an optimized perioperative management strategy for anaesthesia.

Methods

This study is a retrospective single-centre research. Twenty-six SMA patients with severe scoliosis underwent posterior spinal fusion surgery from September 2019 to September 2022 were enroled. The main outcomes were to show the patients' characteristics in anaesthesia, intra- and post-operative periods.

Outcomes

Nineteen patients underwent awake transnasal/transairway intubation. The median anaesthesia time of 25 patients treated under total intravenous anaesthesia was 425 min. After operation, the Cobb angle and correction rate in the coronal plane were median 54.0° and 54.4%. The length of mechanical ventilation with endotracheal intubation in ICU was median 17.5 h in 8 patients. The ICU length of stay of postoperative hospital was median 19 days. Postoperative pneumonia developed in nine patients, atelectasis in two patients, and pleural effusion in six patients. All patients did not need special oxygen therapy after discharge.

Conclusion

Multidisciplinary consultation, lung-protective ventilation strategy, appropriate anaesthetic drugs and reasonable blood transfusion scheme and postoperative monitoring were important in anaesthesia, intraoperative and postoperative periods in the patients of severe scoliosis with spinal muscular atrophy.