The challenges in scoring hypopneas in children: is pulse wave amplitude drop the answer?

BackgroundIdentifying electroencephalogram (EEG) cortical arousals are crucial in scoring hypopneas and respiratory efforts related arousals (RERAs) during a polysomnogram. As children have high arousal threshold, many of the flow limited breaths or hypopneas may not be associated with visual EEG arousals, hence this may lead to potential underestimation of the degree of sleep disordered breathing. Pulse wave amplitude (PWA) is a signal obtained from finger photoplethysmography which correlates directly to finger blood flow. The drop in PWA has been shown to be a sensitive marker for subcortical/autonomic and cortical arousals. Our aim was to use the drop in PWA as a surrogate for arousals to guide scoring of respiratory events in pediatric patients.MethodsTen polysomnograms for patients between the ages of 5–15 years who had obstructive apnea-hypopnea indices between 1 and 5 events/hour were identified. Patients with syndromes were excluded. A drop in PWA signal of at least 30% that lasted for 3 s was needed to identify subcortical/autonomic arousals. Arousals were rescored based on this criteria and subsequently respiratory events were rescored. Paired t-tests were employed to compare PSG indices scored with or without PWA incorporation.ResultsThe sample of 10 children included 2 females, and the average age was 9.8 ± 3.1 years. Overall, polysomnography revealed an average total sleep time of 464.1 ± 25 min, sleep efficiency of 92% +/−4.2, sleep latency of 19.6 ± 17.0 min, rapid eye movement (REM) latency 143 ± 66 min, N1 3.9% +/−2.0, N2 50.3% +/−12.0, N3 28.2% +/−9.1, REM 16.7% +/−4.0, and wakefulness after sleep onset (WASO) 18.1 ± 7.5 min. Including arousals from PWA changes, respiratory indices significantly increased including total AHI (2.3 ± 0.7 vs 5.7 ± 2.1, p < 0.001), obstructive AHI (1.45 ± 0.7 vs 4.8 ± 1.8, p < 0.001), and RDI (2.36 ± 0.7 vs 7.6 ± 2.0, p < 0.001). Likewise, total arousal index was significantly higher (8.7 ± 2.3 vs 29.4 ± 6.5, p < 0.001).ConclusionsThe drop in pulse wave amplitude signal is a useful marker to guide scoring arousals that are not otherwise easily identified in pediatric polysomnography and subsequently helped in scoring respiratory events that otherwise would not be scored. Further studies are needed to delineate if such methodology would affect clinical outcome.     

Analysis of arterial hypertension pharmacotherapy in patients with obstructive sleep apnea syndrome

IntroductionObstructive sleep apnea (OSA) is often connected with arterial hypertension and it could also be a cause of secondary hypertension. Treatment of arterial hypertension and optimal blood pressure level are important for prevention of cardiovascular complications. It is not well known how to treat patients with OSA and arterial hypertension. Also many patients with OSA suffer from metabolic syndrome which worsen their prognosis.AimThe aim of our study was to assess arterial hypertension compensation in patients with metabolic syndrome and moderate to severe OSA and to analyze used pharmacotherapy.Materials and methods85 hypertensive patients (75 men) with metabolic syndrome, average age 53.6 ± 9.3 years, were evaluated using overnight sleep study with diagnosis of OSA, average apnea–hypopnea index (AHI) 56.3 ± 23. Patients underwent 24 h ambulatory blood pressure monitoring (ABPM) and their current pharmacotherapy data were obtained. Appropriate combinations of antihypertensive drugs (patients with metabolic syndrome) were derived from ESH/ESC 2013 guidelines.ResultsArterial hypertension was well compensated in only 11.8% of the patients. 24.7% patients were treated according to current guidelines. Fisher's exact test with analysis of adjusted residues has found higher rate of blood pressure subcompensation in patients treated with triple+ combination of drugs (p = 0.035, 51.4% vs 10%).ConclusionOnly a small number of patients had optimal blood pressure level and were treated according to current ESH/ESC guidelines. We have to constantly appeal to all physicians to perform ABPM in patients with OSA.     

Matrix metalloproteinase 9 (MMP9) level and MMP9 -1562C>T in patients with obstructive sleep apnea: a systematic review and meta-analysis of case-control studies

BackgroundThe peripheral level of matrix metalloproteinase (MMP)-9 and polymorphism of MMP9 -1562C>T in patients with obstructive sleep apnea (OSA) remains controversial. Therefore, the aims of this systemic review and meta-analysis are to assess the MMP9 level in OSA patients and identify the relationship between MMP9 -1562C>T and OSA susceptibility.MethodsThis systematic review was performed following the PRISMA guideline. We searched for studies in major databases, identifying those indexed from inception to July 3, 2019 which related to MMP9 level, MMP9 -1562C>T and OSA. The pooled standardized mean differences (SMDs) and 95% confidence interval (CI) of MMP9 levels were calculated. In addition, the relationship between MMP9 -1562C>T and OSA susceptibility was assessed by three genetic models. The heterogeneity analysis and calculation of the pooled odds ratio (OR) were also performed, followed by quality assessment using the Newcastle-Ottawa Scale (NOS).ResultsIn sum, our review included 15 eligible studies regarding MMP9 level and three regarding MMP9 -1562C>T. The pooled results showed that peripheral level of MMP9 was increased in OSA patients (SMD = 1.37; 95% CI = 1.15–1.59). Furthermore, significant difference of MMP9 level can be found between severe and mild-to-moderate OSA patients (SMD = 28.17; 95% CI = 4.23–52.11) or between moderate-severe and mild OSA (SMD = 36.62; 95% CI = 12.19–61.04). However, no relationship was observed between MMP9 -1562C>T and OSA susceptibility in three genetic models (Homozygote model, OR = 1.37; 95% CI = 0.87–2.18); (Recessive model, OR = 1.42; 95% CI = 0.83–2.42); (Allele model, OR = 1.07; 95% CI = 0.96–1.18).ConclusionsThis systemic review and meta-analysis indicated that the level of MMP9 was increased in patients with OSA and this increase is relevant to OSA severity. Moreover, the relationship between MMP9 -1562 C>T and OSA susceptibility has currently not been proven by current merging values. Further analyses with larger sample size are required to verify these associations.     

基于“肝主疏泄”治疗便秘的体会

中医论治便秘多从肺、脾胃、肾等脏着手,对肝脏的调理不够重视。然笔者却认为便秘之病症与肝的关系更为密切一些。本文从肝主疏泄的理论依据、肝与便秘的关系、从肝论治便秘等三方面论述,并总结两个治疗医案进行佐证,以飨同道。