The Thoracic Inlet Index in patients with tracheal obstruction caused by chest wall deformity: Validation in patients and age-matched controls

Variation in thoracic inlet measurements and its correlation with pulmonary dysfunction in kyphoscoliotic deformities: a prospective case-control study

BACKGROUND

Pulmonary dysfunction in thoracic kyphoscoliosis has been correlated with chest wall distortion, uneven trunk growth and restrictive pattern. The study aims to analyse the variation in thoracic inlet measurements on pulmonary dysfunction with varying curve magnitude and thoracic cage parameters.

METHODS

In a non-randomised, prospective case-control study, 80 consecutive patients with thoracic kyphoscoliosis were divided into 3 groups based on Cobb angle: Group 1 (31-50), Group 2 (51-80) and Group 3 (> 80). Thoracic inlet measurement was calculated by thoracic inlet index (TI) on MRI at the sternal level. Pulmonary function and thoracic cage parameters [hemi thorax height, rib-apex distance, AP chest diameter at sternal level and transverse thoracic diameter] were documented. TI values were compared with 20 age-matched asymptomatic controls. Multivariate correlation and regression analysis were performed to investigate the correlations.

RESULTS

The mean age of the study cohort was 14.1 ± 4.4 years, including Group 1 (6 patients), Group 2 (55 patients) and Group 3 (19 patients) versus 12.9 ± 2.2 years in controls. The mean TI was 2.8 ± 0.56 in Group 1, 3.7 ± 0.9 in Group 2 and 4.0 ± 1.12 in Group 3 versus 2.6 ± 0.43 in controls. Pulmonary dysfunction was severe with TI > 7.1 (p < 0.001) in Group 3 patients with thoracic hypokyphosis. Multivariate regression for thoracic parameters and TI > 5.6 showed significant correlation of pulmonary dysfunction in Group 2 and 3 curves with apex between T1 and T4, whereas transverse thoracic diameter, rib-apex distance and hemi thorax height were weakly associated.

CONCLUSION

Thoracic inlet index (TI), a neglected pre-operative variable associated with pulmonary dysfunction in thoracic kyphoscoliosis, can be evaluated on MRI without an additional cost and radiation.

LEVEL OF EVIDENCE: 3

Unsuspected severe tracheal stenosis and tracheomalacia after correction surgery for congenital scoliosis: A case report

Tracheal stenosis and tracheomalacia in patients with congenital scoliosis are serious and rare conditions caused by congenital dysplasia, postintubation injury, trauma, and tracheal tumor. Anesthesia of a child with tracheal stenosis is challenging for anesthesiologists. We describe an 8-year-old female patient developed severe tracheal stenosis and tracheomalacia after growing rod implantation for congenital scoliosis. Comprehensive assessment of preoperative pulmonary function and airway morphology, which can be neglected clinically, should be performed in congenital scoliosis patients.

An Analysis of Tracheostomy Complications in Pediatric Patients With Scoliosis

OBJECTIVES/HYPOTHESISAL

To analyze tracheostomy-related complications in pediatric patients with scoliosis.

STUDY DESIGN

Retrospective chart review.

METHODS

A retrospective chart review of all patients with tracheostomy and scoliosis was performed at a single institution. The charts were reviewed for variables including difficulties with tracheostomy tube changes, poor positioning of tube, abnormal appearance of trachea, and emergency room visits and admissions for complications. Decannulation rates were also identified.

RESULTS

About 102 patients met inclusion criteria, 96 (94.1%) had scoliosis involving the thoracic spine, and 4 had scoliosis involving the cervical spine; 13 (12.8%) patients had documented poor positioning on tracheoscopy; 31 patients (30.3%) had at least one emergency room visit or admission for complications, such as accidental decannulation or bleeding from the tracheostomy; 19 (18.6%) patients required at least one tube change due to poor positioning, with 7 (6.9%) requiring multiple changes; 18 (17.7%) had reported difficulties with home tube changes. Custom length tubes were required in 9 patients (8.8%). The level of scoliosis was not associated with any of these complications. Abnormalities of the trachea, such as tortuosity, obstructive granulomas, or tracheomalacia, were seen in 35 patients (34.3%) on bronchoscopy. Scoliosis repair was performed in 18 patients (17.65%), of which two achieved decannulation. Ten patients (9.8%) overall were decannulated.

CONCLUSION

A portion of patients with scoliosis who are tracheostomy-dependent have anatomical abnormalities of the trachea and poor positioning of the tracheostomy tube. Decannulation rates are also lower in this population compared to the literature. Further work is required to elucidate if scoliosis predisposes patients toward tracheostomy-related complications.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

Bezold-Jarisch reflex causing bradycardia and hypotension in a case of severe dystrophic cervical kyphotic deformity: a case report and review of literature

PURPOSE

A 17-year-old adolescent with neurofibromatosis and severe cervicothoracic deformity was identified to have thoracic inlet compression leading to bradycardia and hypotension, only during prone positioning, and we discuss its successful management.

METHODS

Preoperative halo-gravity traction reduced the deformity from 126° to 91°. During prone positioning, sudden onset bradycardia was followed by asystole, which disappeared immediately on turning over to supine position. Surgery was called off after two additional failed attempts of prone positioning.

RESULTS

A retrospective analysis of CT and MRI showed severe narrowing of the thoracic inlet. In this patient, the right thoracic inlet was severely narrow, and prone positioning caused a further dynamic compromise stimulating right vagal nerve. The right vagus supplies the sinoatrial node, which is the natural pacemaker of the heart, and its stimulation causes sympathetic inhibition. Bezold-Jarisch reflex is a cardio-inhibitory reflex occurring due to vagal stimulation resulting in sudden bradycardia, asystole, and hypotension. To facilitate prone positioning, the medial end of the clavicles, along with limited manubrium excision, was performed relieving the vagal compression. C2-T4 instrumented decompression followed by anterior reconstruction and cervical plating was performed. The postoperative period was uneventful, and the final deformity was 45°.

CONCLUSION

Bezold-Jarisch Reflex as a result of narrow thoracic inlet caused by cervical kyphosis and compensatory hyperlordosis of the upper thoracic spine has never been reported. This case highlights the need to introspect into thoracic inlet morphology in severe cervicothoracic deformities. Thoracic inlet decompression is an efficient way of addressing this unique complication.

Critical Airway Stenosis in an Adolescent Male With Pompe Disease and Thoracic Lordosis: A Case Report

An adolescent male with late-onset Pompe disease (glycogen storage disease type II) presented with a history of restrictive airway disease and a near-cardiorespiratory arrest during anesthesia for a liver biopsy initially thought to be due to bronchospasm. During a subsequent posterior spinal fusion procedure, he suffered cardiorespiratory arrest resulting in the procedure being aborted. Bronchoscopy performed shortly after resuscitation revealed an undiagnosed narrowing of the distal trachea and bronchi. This is the first description of a patient with late-onset Pompe disease with undiagnosed critical tracheal stenosis due to the progression of thoracic lordosis, which was ultimately relieved by posterior spinal fusion.