Heterogeneity in the evaluation of suspected MIS-C: a cross-sectional vignette-based survey.

BACKGROUND AND OBJECTIVES: Multisystem Inflammatory Syndrome in Children (MIS-C) is an emerging complication of COVID-19 which lacks a definitive diagnostic test and evidence-based guidelines for workup. We sought to assess practitioners' preferences when initiating a workup for pediatric patients presenting with symptoms concerning for MIS-C. METHODS: In a cross-sectional vignette-based survey, providers were presented with clinical vignettes of a patient presenting with 24 h of fever from a community with high rates of COVID-19. Respondents were asked about their general practices in pursuing a workup for potential MIS-C including testing obtained, criteria for diagnosis, and timing to confirm or rule out the diagnosis. RESULTS: Most of the 174 respondents were physicians from the United States at academic medical centers. The majority of providers would not initiate MIS-C workup for fever and non-specific symptoms unless the fever lasted more than 72 h. Skin rash, abdominal pain, and shortness of breath were symptoms that raised greatest concern for MIS-C. Most providers would obtain COVID-19 PCR or antigen testing, plus blood work, in the initial workup. The list of laboratory studies providers would obtain is extensive. Providers primarily rely on cardiac involvement to confirm a MIS-C diagnosis, and establishing a diagnosis takes 24-48 h. CONCLUSIONS: Significant heterogeneity exists amongst providers as to when to initiate the MIS-C workup, the order and content of the workup, and how to definitively diagnose MIS-C. A diagnostic test with high sensitivity and specificity for MIS-C and refined evidence-based guidelines are needed to expedite diagnosis and treatment.

Combination Tonsillectomy and Hypoglossal Nerve Stimulation for Sleep Apnea Patients With Oropharyngeal Lateral Wall Collapse.

OBJECTIVE: The efficacy of hypoglossal nerve stimulation (HGNS) therapy is limited by obstruction of the oropharyngeal lateral walls (OLWs). Our objective was to investigate the effect of palatine tonsillectomy on HGNS efficacy in obstructive sleep apnea (OSA) patients with OLW collapse. STUDY DESIGN: Case-control study of patients with moderate-to-severe OSA, complete-or-partial OLW collapse, and small tonsils (1 - 2+). Concomitant palatine tonsillectomy and HGNS (HGNS+T) were compared against a control group of patients who underwent HGNS alone. SETTING: Single academic institution. METHODS: Study outcomes were measures of HGNS efficacy defined as a %reduction in apnea-hypopnea index (AHI) (primary) and successful treatment response (50% AHI reduction to <15/h, logistic regression), respectively. Regression analyses quantified the additional effect of tonsillectomy (HGNS+T vs HGNS alone, independent variable) on HGNS efficacy. Analyses were adjusted for OLW collapse severity (complete vs partial), tonsil size, age, sex, body mass index, and baseline AHI. RESULTS: Nineteen patients underwent HGNS+T and had follow-up sleep testing for the current analysis. The control group (HGNS alone) consisted of 78 patients. Baseline demographics and OSA severity were similar between the groups, except HGNS+T group had increased prevalence of complete OLW collapse. Linear regression demonstrated that adding tonsillectomy resulted in an additional 22.9% [7.5, 35.2] reduction in AHI [95% confidence interval, CI] (P = .006), and 8.6 [1.7,43.4] (P = .010) greater odds [95% CI] of a successful treatment response with HGNS. CONCLUSION: Compared to historically poorer outcomes of HGNS in patients with OLW collapse, these early results suggest combining tonsillectomy with HGNS may represent a promising strategy to improve success rates.

Physiological Determinants of Snore Loudness.

Rationale: The physiological factors modulating the severity of snoring have not been adequately described. Airway collapse or obstruction is generally the leading determinant of snore sound generation; however, we suspect that ventilatory drive is of equal importance. Objective: To determine the relationship between airway obstruction and ventilatory drive on snore loudness. Methods: In 40 patients with suspected or diagnosed obstructive sleep apnea (1-98 events/hr), airflow was recorded via a pneumotachometer attached to an oronasal mask, ventilatory drive was recorded using calibrated intraesophageal diaphragm electromyography, and snore loudness was recorded using a calibrated microphone attached over the trachea. "Obstruction" was taken as the ratio of ventilation to ventilatory drive and termed flow:drive, i.e., actual ventilation as a percentage of intended ventilation. Lower values reflect increased flow resistance. Using 165,063 breaths, mixed model analysis (quadratic regression) quantified snore loudness as a function of obstruction, ventilatory drive, and the presence of extreme obstruction (i.e., apneic occlusion). Results: In the presence of obstruction (flow:drive = 50%, i.e., doubled resistance), snore loudness increased markedly with increased drive (+3.4 [95% confidence interval, 3.3-3.5] dB per standard deviation [SD] change in ventilatory drive). However, the effect of drive was profoundly attenuated without obstruction (at flow:drive = 100%: +0.23 [0.08-0.39] dB per SD change in drive). Similarly, snore loudness increased with increasing obstruction exclusively in the presence of increased drive (at drive = 200% of eupnea: +2.1 [2.0-2.2] dB per SD change in obstruction; at eupneic drive: +0.14 [-0.08 to 0.28] dB per SD change). Further, snore loudness decreased substantially with extreme obstruction, defined as flow:drive <20% (-9.9 [-3.3 to -6.6] dB vs. unobstructed eupneic breathing). Conclusions: This study highlights that ventilatory drive, and not simply pharyngeal obstruction, modulates snore loudness. This new framework for characterizing the severity of snoring helps better understand the physiology of snoring and is important for the development of technologies that use snore sounds to characterize sleep-disordered breathing.