Pediatric obstructive sleep apnea: a prospective observational study of respiratory events in the immediate recovery period after adenotonsillectomy.

BACKGROUND: Adenotonsillectomy is often curative for pediatric obstructive sleep apnea, yet children remain at high risk of respiratory complications in the postoperative period. We sought to determine the incidence and risk factors for respiratory depression and airway obstruction, as well as clinically apparent respiratory events in the post-anesthesia care unit (PACU) in high-risk children after adenotonsillectomy. METHODS: In this prospective cohort study, we enrolled 60 high-risk children having adenotonsillectomy. Our primary outcome was respiratory depression and airway obstruction in the PACU measured using a noninvasive respiratory volume monitor (RVM) and defined by episodes of predicted minute ventilation less than 40% for at least 2 min. We measured clinically apparent respiratory events using continuous observation by trained study staff. RESULTS: The median (range) age of our sample was 4 years (1, 16) and 27 (45%) were female. Black and Hispanic race children comprised 80% (n = 48) of our cohort. Thirty-nine (65%) had at least one episode of PACU respiratory depression or airway obstruction measured using the RVM, while only 21 (35%) had clinically apparent respiratory events. Poisson regression demonstrated the following associations with an increase in episodes of respiratory depression and airway obstruction: BMI Z-score less than -1 (estimate 3.91; [95%CI 1.49-10.23]), BMI Z-score 1-2 (estimate 2.04; [1.20-3.48]), and two or more comorbidities (estimate 1.96; [1.11-3.46]). CONCLUSIONS: Respiratory volume monitoring in the immediate postoperative period after pediatric high-risk adenotonsillectomy identifies impaired ventilation more frequently than is clinically apparent.

Angelman and Prader-Willi Syndromes: Sister Imprinting Disorders With High Complication Rates Following Spinal Deformity Surgery.

We sought to examine the modern surgical treatment of spinal deformity associated with sister imprinting disorders, Prader-Willi syndrome (PWS) and Angelman syndrome (AS), with emphasis on the specific complications encountered in these patient populations. Fifteen patients with PWS and 5 patients with AS who underwent surgical intervention for spinal deformity between 2000 and 2018 were identified. Postoperative complications were classified using the modified Clavien-Dindo-Sink (CDS) system and further categorized into specific subtypes including excessive drainage, dehiscence, implant failure, infection, and delayed wound healing. Perioperative and final follow-up radiographic data were analyzed. Mean age at surgery was 12.9 years (range, 4-21 years) with mean follow-up of 46.1 months (range, 1-145 months). There were postoperative complications in 17 patients (85%). Ten major complications (CDS ≥ 3) occurred in 9 patients (45%). These included 5 infections requiring reoperation, 1 seroma requiring drainage, 2 severe cervical-thoracic deformities requiring reoperation, 1 implant failure requiring reoperation, and 1 death secondary to fungal sepsis and thromboembolic disease. Eight additional patients (40%) had minor complications (CDS 1 or 2). Eight intraoperative complications occurred in 5 patients (25%), including loss of neuromonitoring signals and cerebrospinal fluid leaks. Surgical intervention for scoliosis in PWS and AS continues to have high complication rates secondary to medical and behavioral comorbidities found in these patient populations. The exact etiology of the high complication rates encountered cannot be definitively stated, but both syndromes frequently present with a number of unique features that may predispose patients to develop surgical complications. [Orthopedics. 2023;46(4):e223-e229.].

Curve Characteristics and Surgical Outcomes in Scoliosis Associated With Childhood Sternotomy or Thoracotomy.

BACKGROUND: The purpose of this study is to describe curve characteristics and postoperative outcomes in patients undergoing spinal fusion (SF) to treat thoracogenic scoliosis related to sternotomy and/or thoracotomy as a growing child. METHODS: A retrospective review of electronic medical records of all patients with Post-Chest Incision scoliosis treated with SF was performed at 2 tertiary care pediatric institutions over a 19-year period. Curve characteristics, inpatient, and outpatient postoperative outcomes are reported. RESULTS: Thirty-nine patients (62% female) were identified. Eighteen had sternotomy alone, 14 had thoracotomy alone, and 7 had both. Mean age at the time of first chest wall surgery was 2.5 years (range: 1.0 d to 14.2 y). Eighty-five percent of patients had a main thoracic curve (mean major curve angle 72 degrees, range: 40 to 116 degrees) and 15% had a main lumbar curve (mean major curve angle 76 degrees, range: 59 to 83 degrees). Mean thoracic kyphosis was 40 degrees (range: 4 to 84 degrees). Mean age at the time of SF was 14 years (range: 8.2 to 19.9 y). Thirty-six patients had posterior fusions and 3 had combined anterior/posterior. Mean coronal curve correction measured at the first postoperative encounter was 53% (range: 9% to 78%). There were 5 (13%) neuromonitoring alerts and 2 (5%) patients with transient neurological deficits. Mean length of hospital stay was 9±13 days. At an average follow-up time of 3.1±2.4 years, 17 complications (10 medical and 7 surgical) were noted in 9 patients for an overall complication rate of 23%. There was 1 spinal reoperation in the cohort. 2/17 (12%) complications were Clavien-Dindo-Sink class III and 5/17 (29%) were class IV. CONCLUSION: Kyphotic thoracic curves predominate in patients with Post-Chest Incision scoliosis undergoing SF. Although good coronal and sagittal plane deformity can be expected after a fusion procedure, postoperative complications are not uncommon in medically complex patients, often necessitating longer postoperative stays. LEVEL OF EVIDENCE: Level III.

Use of transcranial motor-evoked potentials to provide reliable intraoperative neuromonitoring for the Charcot-Marie-Tooth population undergoing spine deformity surgery.

PURPOSE: Intraoperative neuromonitoring (IONM) has historically been difficult to obtain in patients with Charcot-Marie-Tooth (CMT) disease. Transcranial motor-evoked potentials (TcMEPs) have been found to be safe and effective for other spinal deformity patients. Our objective was to determine the effectiveness of TcMEP monitoring in patients with CMT. METHODS: An IRB-approved, retrospective review of CMT patients undergoing spinal deformity surgery assessing TcMEP, somatosensory-evoked potential (SSEP), and neurogenic motor evoked potential (NMEP) IONM was performed. A 2:1 matched cohort control group of idiopathic spinal deformity patients was used. A waveform grading system was applied to review baseline TcMEP reliability and quality, which was validated via intraclass correlation coefficient amongst five raters. RESULTS: Twenty-three CMT patients (26 surgical cases) were identified. The use of TcMEP improved the ability to obtain baseline IONM when compared to SSEP (83% vs. 20%; p < 0.001) and NMEP (83% vs. 18%; p = 0.003). Baseline monitoring was obtained less often for CMT patients using SSEP (20% vs. 100%; p < 0.001) and TcMEP (83% vs. 100%; p = 0.111) compared to idiopathic patients. Sweep length (time from stimulation waveform evaluation) and maximum stimulation voltage were higher in the CMT group (289 ms vs. 111 ms p = 0.007 and 740 V vs. 345 V p = 0.089, respectively). CONCLUSION: TcMEP monitoring significantly improves the ability to provide IONM for CMT patients undergoing spinal deformity surgery. Utilizing longer sweep lengths enhances the ability to attain baseline TcMEP readings, allowing surgeons to more safely proceed with surgery for these complex patients. LEVEL OF EVIDENCE: Therapeutic-Level III.

Lack of in-brace x-rays in compliant AIS patients wearing full-time TLSO braces associates with failure.

BACKGROUND: In-brace correction and brace compliance with thoraco-lumbo-sacral orthotic (TLSO) braces are associated with successful treatment of adolescent idiopathic scoliosis (AIS). This paper compares patients who had consistent radiographic documentation of in-brace correction to those who did not. METHODS: All skeletally immature (Risser 0-2) patients were treated for AIS (25-45°) with full-time TLSO braces that had compliance temperature monitors. All patients wore their braces at least 12 h a day. Brace failure was defined as curve progression to a surgical magnitude (≥ 50°). All patients were followed until brace discontinuation. RESULTS: Ninety patients (F 82, M 8) with an average age of 12.1 (10.1-15.0) years, Risser grade 0 (0-2), BMI percentile 48.5 (0.0-98.8), and daily brace wear of 16.5 (12.1-21.6) h/day were treated for 24.3 (8.0-66.6) months. Patients went through 1.7 (1-4) braces on average. Forty-two out of 90 (46.7%) patients had some amount of brace time with an unknown in-brace correction, which, on average, was 66.1% of their total treatment course (11.5-100). On univariate analysis, patients that did not have a repeat in-brace x-ray with major brace adjustments or new brace fabrication tended to be more skeletally immature (Risser 0 and tri-radiate open, p = 0.028), wear more braces throughout their treatment (2.0 vs 1.4, p < 0.001), were treated for a longer period of time (27 vs 22 months, p = 0.022), and failed bracing more often (47.6% vs 22.9%, p = 0.014). CONCLUSIONS: Patients who did not have new in-brace x-rays with major brace adjustments and/or new brace fabrication were 3.1 (95% CI 1.2-7.6) times more likely to fail bracing than patients who were re-checked with new in-brace x-rays. TRIAL REGISTRATION: ClinicalTrials.gov- NCT02412137 , initial registration date April 2015 LEVEL OF EVIDENCE: III.

Ponte osteotomies in a matched series of large AIS curves increase surgical risk without improving outcomes.

PURPOSE: The routine use of Ponte osteotomies in adolescent idiopathic scoliosis (AIS) surgery is controversial with conflicting data for coronal plane correction and little analysis in the sagittal plane. The objective of this study was to analyze the efficacy of Ponte osteotomies in large curve AIS. METHODS: A single institution, prospectively-collected series of consecutive AIS patients who had Ponte osteotomies (P cohort) was directly matched to patients with no Pontes (NP cohort) by age, gender, Lenke classification, surgeon, coronal, and sagittal Cobb angles. The radiographic review included adjusted values using a 3D-derived published formula for preoperative T5-T12 kyphosis. Patient-reported outcomes (PROs) were assessed with the SRS-30 and Spinal Appearance Questionnaire (SAQ). RESULTS: There were 68 patients (34/cohort) with minimum 2-year follow-up with no differences between P and NP cohorts in age, preoperative coronal Cobb (74.5° vs 70.8°), flexibility index, measured or 3D-adjusted T5-T12 kyphosis. Rod material/diameter, fusion levels, blood loss, and operative time did not differ, but implant density was higher in the P group (1.53 vs 1.31, p < 0.001). The P group had 7.9% greater coronal Cobb correction (66.6% vs 58.7%, p < 0.003) without difference in final Cobb angles (24.7° vs. 29.1°, p = 0.052). There were no differences in measured or adjusted T5-T12 kyphosis in the sagittal plane. The P group had a 15% rate of critical intraoperative neuromonitoring changes versus 0% in the NP group (p = 0.053). At follow-up, there were no differences in scoliometer measurements or any domain of SRS-30 or SAQ scores. CONCLUSION: In this first reported matched series of AIS patients, Ponte osteotomies provide small radiographic gains in the coronal plane with no improvement in the sagittal plane and no change in truncal rotation. There was a higher risk of critical intraoperative neuromonitoring changes, and no benefits in patient-reported outcomes. This calls into question the routine use of Ponte osteotomies in AIS, even for curves averaging 70 degrees. LEVEL OF EVIDENCE: II.

Spinal balance and lumbar curve stability after selective thoracic fusion in idiopathic scoliosis.

PURPOSE: Selective thoracic fusion (STF) for double curve patterns in idiopathic scoliosis is an attractive treatment option. However, short-term coronal decompensation and truncal imbalance are known findings. Previous studies with hook constructs showed that eventually balance is achieved via an increase in lumbar curve magnitude, as the lumbosacral obliquity did not change following surgery. Our aim is to investigate patients with idiopathic curves who underwent STF using all-pedicle screw constructs to determine if the uninstrumented lumbar curve and lumbosacral obliquity responded in the same manner as was previously reported with all-hook constructs. METHODS: 102 consecutive patients with Lenke 1B, 1C or 3C curves who underwent STF using all-screw constructs at a single institution were included in this study. Radiographic assessment was performed, and patient reported outcomes were obtained. Subgroup analyses were performed based on preoperative thoracic: lumbar curve ratio as well as lumbar curve magnitude. RESULTS: Overall, the patients showed statistically significant improvement in both trunk shift and L4-pelvis obliquity at final follow-up. The uninstrumented lumbar curves trended toward improvement over time, but did not reach statistical significance (p = 0.107). SRS-30 scores were statistically significantly improved in multiple domains. CONCLUSION: Selective thoracic fusion is an excellent treatment option in most double curve patterns. Balance in the coronal plane is predictably achieved at 2-year follow-up. The lumbosacral obliquity improves more with screw technology than was previously found with hook constructs; therefore, the improvement in balance over time does not depend upon an increase in the uninstrumented lumbar curve. LEVEL OF EVIDENCE: IV.

Continued deterioration in pulmonary function at average 23-year follow-up from early thoracic fusion in non-neuromuscular scoliosis.

PURPOSE: Historically, early-onset scoliosis was treated with early fusion to prevent further deformity at the expense of thoracic growth. This has proven to have a detrimental effect on pulmonary function. The purpose of this study is to evaluate patients' pulmonary and functional status at long-term follow-up after undergoing thoracic fusion at a young age. METHODS: All patients at a single institution who had undergone thoracic spinal fusion prior to age nine with minimum 13-year follow-up were eligible. Patients underwent pulmonary function testing, radiographic analysis, and functional testing. Results were compared to the patients' previous pulmonary function data at average of 11 years post-surgery. RESULTS: Fifteen out of twenty-eight eligible patients returned for testing. The average age at the time of surgery was 3.3 years (range 0.9-8.4 years) with follow-up of 23.6 years (range 13.2-33.2 years). There was a statistically significant interval decline in predicted forced vital capacity (42.8% versus 54.7% of normal predicted values, p = 0.0001) and predicted forced expiratory volume in one second (42.2% versus 55.2% of normal predicted values, p = 0.0001) when compared to previous follow-up. There was a strong positive correlation between thoracic height and forced vital capacity (r = 0.925, p = 0.002). CONCLUSIONS: Pulmonary function in patients who had undergone thoracic spinal fusion for scoliosis prior to the age of six continues to decline into adulthood at a rate that is faster than that of their peers. The majority of these patients have clinically important restrictive lung disease, which can be fatal. Alternative treatment strategies should be considered. LEVEL OF EVIDENCE: III.

Intraoperative Prone Radiographs During Scheuermann Kyphosis Correction Closely Estimate Standing Thoracic and Lumbar Parameters at 2 Years.

BACKGROUND: In patients with Scheuermann kyphosis (SK) undergoing posterior spinal fusion with instrumentation (PSFI), intraoperative lateral radiographs assess deformity correction in the prone position. The relationship between thoracic and (partially un-instrumented) lumbar parameters on prone intraoperative versus standing postoperative radiographs is unknown. METHODS: Forty-five consecutive patients with SK who underwent PSFI between 2007 and 2014 were reviewed. Thoracic kyphosis (TK), lumbar lordosis (LL), instrumented level kyphosis [upper instrumented vertebrae (UIV)-lower instrumented vertebrae (LIV)], and traditional sagittal parameters were recorded from preoperative standing, intraoperative prone, first outpatient standing, and >2-year standing radiographs and time periods were compared. Exclusion criteria included reduction modification after intraoperative radiographs and postoperative construct revision prohibiting comparison to initial intraoperative radiographs. RESULTS: Twenty-five patients averaging 16 (12 to 20) years old during surgery with 3.1 (2 to 7) years follow-up met inclusion criteria. Average surgical variables included: 13±1 fusion levels, UIV at T2, LIV at L3, 3.8±1.6 osteotomies per patient, and 43±9% correction of TK. Preoperative TK and LL measured 82 and 76 degrees, respectively. TK on intraoperative (47 degrees), 6-week (49 degrees), and >2-year (50 degrees) radiographs changed significantly only between intraoperative and >2-year radiographs (P=0.03) by just 3 degrees. LL increased 5 degrees from intraoperative prone to 6-week standing radiographs (51 to 56 degrees, P=0.01) without further significant change at >2 years (59 degrees, P=0.09). Instrumented levels (UIV-LIV) had increased kyphosis at 6 weeks (32 to 35 degrees, P=0.01) without further change at >2 years (36 degrees, P=0.06). CONCLUSIONS: TK on intraoperative prone radiographs during PSFI for SK should match the standing TK ∼6 weeks later. Intraoperative prone LL only slightly increases on early standing radiographs. Assuming a routine postoperative course, intraoperative radiographs slightly underestimate TK (by 3 degrees) and LL (by 8 degrees) on >2-year standing radiographs. These parameters (TK, LL, UIV-LIV) are visualized during surgery and should be used in future studies to predict long-term outcomes. LEVEL OF EVIDENCE: Level IV-retrospective study.

Two AIS spine surgeries on the same day by the same surgeon: is performance and outcome the same for the second patient?

STUDY DESIGN: Retrospective case-controlled study. OBJECTIVES: To analyze the overall performance and outcome of two-a-day surgery days for adolescent idiopathic scoliosis (AIS). As a method to improve efficiency and operating room utilization, some surgeons are now performing two surgeries for AIS in a single day. METHODS: A prospectively collected series of AIS patients who underwent posterior spinal fusion on the same day as a second AIS patient by the same surgeon and surgical team were retrospectively reviewed. Patients who underwent same-day surgery (SD) were grouped according to whether they were the first (SD1) or second (SD2) case of the day and were matched (M1 and M2) by surgeon, curve magnitude, Lenke classification, and fusion levels. Comparisons were made: SD1 vs. SD2, SD1 vs. M1, and SD2 vs. M2. RESULTS: There were 56 patients, with no differences between groups in age, gender, BMI, or curve magnitude (66° vs. 62° vs. 65° vs. 63°). Surgical time was shorter for the SD1 group (17.2 min/level) compared to M1 (20.5 min/level) for a 15% operative time reduction of 44 min (p = 0.008). There were no differences between the groups in curve correction (65.8% vs. 62.8% vs. 66.1% vs. 58.5%), estimated blood loss (EBL), length of stay, or complication rate. One SD2 patient had a malpositioned screw that required revision. There were no other complications. CONCLUSIONS: When performing two AIS surgeries on the same day, surgical time was reduced by 44 min, or 15%, on the first case compared to a matched control. This may be a reflection of the team moving along more efficiently, given the full operative day scheduled. The performance measures of curve correction, EBL, complications, and length of stay did not decline in this new model, and no increased incidence of complications was seen.

The incidence and risk factors for perioperative allogeneic blood transfusion in primary idiopathic scoliosis surgery.

STUDY DESIGN: Case-control study. OBJECTIVES: Evaluate the rate and risk factors for perioperative allogeneic blood transfusion (ABT) in primary idiopathic scoliosis surgery at a single institution. Avoiding perioperative ABT is ideal as transfusions are associated with adverse reactions, increased rates of infection, prolonged hospitalization, additional laboratory testing, and increased cost. Risk factors identified in other studies have differed, and to our knowledge, few studies have identified clinical strategies to predict patients at high risk for ABT. METHODS: We reviewed 402 idiopathic scoliosis patients who underwent primary posterior spinal fusion and instrumentation (PSFI) at a single institution from 2015 to 2017. Medical records and radiographs were reviewed for all patients. Transfused patients were compared to the remaining cohort to find significant differences and identify predictors of higher ABT risk. RESULTS: ABT occurred in 73 patients (18.2%), with the majority of transfusions occurring intraoperatively (41%) or postoperatively on the day of surgery (25%). The seven surgeons involved varied significantly in incidence of ABT (2.4-35.8%, p = 0.002). Patients who had ABT were younger (13.3 vs. 14.1 years, p < 0.01), had lower BMI (48th vs. 61st percentile, p < 0.001), and lower preoperative hemoglobin (13.1 vs. 13.7 g/dL, p < 0.01). Greater preoperative major Cobb angle (69° vs. 61.5°, p < 0.001), number of fusion levels (11.8 vs. 10.3, p < 0.001), and estimated blood loss (770 vs. 448 mL, p < 0.001) also predicted ABT. CONCLUSIONS: ABT was associated with several risk factors, five of which are known preoperatively. Surgeons can use knowledge of these risk factors to assess transfusion risk preoperatively and plan surgery, blood management, and laboratory testing accordingly. The development of best practices for ordering ABT is possible given the variation amongst providers. LEVEL OF EVIDENCE: Level III.