Oscillometry: A substitute of spirometry in children with neuromuscular diseases?

INTRODUCTION: Spirometry plays an important role in the assessment of possible respiratory failure in children with neuromuscular diseases (NMDs). However, obtaining reliable spirometry results is a major challenge. We studied the relation between oscillometry and spirometry results. Oscillometry is an easy, noninvasive method to measure respiratory resistance R and reactance X. We hypothesized an increased R and reduced X in patients with more reduced lung function. METHODS: In this prospective single-center study, we included all children with NMDs able to perform spirometry. We consecutively measured R and X at 5, 11, and 19 Hz and (forced) vital capacity, peak expiratory flow. Spearman correlation coefficients and positive and negative predictive values were calculated. Regression curves were estimated. RESULTS: We included 148 patients, median age 13 years (interquartile range: 8-16). A negative correlation was found between R and spirometry outcomes (Spearman correlation coefficient [ρ]: -0.5 to -0.6, p < 0.001). A positive correlation was found between X (i.e., less negative outcomes) and spirometry outcomes (ρ: 0.4-0.6, p < 0.001). Highest correlation was found at lower frequencies. Regression analysis showed a nonlinear relation. Measurement of inspiratory and expiratory R and X did not provide added value. Positive predictive values of 80%-85% were found for z-scores of R measured at 5 Hz versus (F)VC ≤ 60%. CONCLUSION: We found a nonlinear relation between oscillometry and spirometry results with increased R and reduced X in patients with more restrictive lung function decline. Given the difficulties with performing spirometry, oscillometry may be a promising substitute.

Pretreatment tumor sampling and prognostic factors in patients with soft-tissue sarcoma of the head and neck.

BACKGROUND: Insufficient preoperative work-up and consequent intralesional or marginal resection of soft-tissue sarcomas of the head and neck (STSHNs) is common. METHODS: This retrospective cohort study comprised 63 patients with STSHN treated at the Helsinki University Hospital between 2005 and 2017. We assessed the effect of pretreatment tumor sampling on surgical margin status and need for supplemental surgery, as well as prognostic factors and survival. RESULTS: The lack of representative pretreatment biopsy specimen was associated with unfavorable margin status. Primary surgery at a non-academic center was associated with need for supplemental surgery. The 3-year overall survival (OS) was 68%, disease-specific survival (DSS) 71%, and recurrence-free survival (RFS) 61%. Higher tumor grade and primary tumor size over 5 cm were associated with reduced DSS. CONCLUSIONS: Diagnosis and management of STSHNs should be centralized to experienced academic centers. Decision-making between needle biopsy, open biopsy, or upfront radical surgery depends on tumor location and size.