Continuous and bilevel positive airway pressure may improve radiotherapy delivery in patients with intra-thoracic tumors

Background

Minimizing tumor motion in radiotherapy for intra-thoracic tumors reduces side-effects by limiting radiation exposure to healthy tissue. Continuous or Bilevel Positive Airway Pressure (CPAP/BiPAP) could achieve this, since it could increase lung inflation and decrease tidal volume variability. We aim to identify the better CPAP/BiPAP setting for minimizing tumor motion.

Methods

In 10 patients (5 with lung cancer, 5 with other intra-thoracic tumors), CPAP/BiPAP was tested with the following settings for 10 min each: CPAP 5, 10 and 15 cmH2O and BiPAP 14/10 cmH2O with a lower (7 breaths/min) and higher back-up respiratory rate (BURR initially 1 breath/min above the spontaneous breathing frequency, with the option to adjust if the patient continued to initiate breaths). Electrical impedance tomography was used to analyse end-expiratory lung impedance (EELI) as an estimate of end-expiratory lung volume and tidal impedance variation (TIV) as an estimate of tidal volume.

Results

Nine out of ten patients tolerated all settings; one patient could not sustain CPAP-15. A significant difference in EELI was observed between settings (χ2 22.960, p < 0.001), with most increase during CPAP-15 (median (IQR) 1.03 (1.00 - 1.06), normalized to the EELI during spontaneous breathing). No significant differences in TIV and breathing variability were found between settings.

Conclusions

This study shows that the application of different settings of CPAP/BiPAP in patients with intra-thoracic tumors is feasible and tolerable. BiPAP with a higher BURR may offer the greatest potential for mitigating tumor motion among the applied settings, although further research investigating tumor motion should be conducted.

Lung ultrasound for prediction of surfactant requirement in Indian preterm neonates: a diagnostic accuracy study

Surfactant replacement for respiratory distress syndrome (RDS) is currently guided by oxygen (FiO2) requirement in preterm neonates. Lung ultrasound (LUS) has emerged as an important predictive tool; however, there is a paucity of evidence from developing countries. The objective of this study was to determine the diagnostic accuracy of the LUS score in comparison to standard criteria based on FiO2 requirement for prediction of surfactant requirement. In this prospective study, preterm neonates of < 34 weeks' gestation with RDS were included within 2 h of life. Surfactant was administered if the FiO2 requirement exceeded 30%. Baseline characteristics, respiratory parameters, and LUS clips were recorded soon after birth and compared between the surfactant and non-surfactant groups. LUS scoring was later performed by masked assessors which was not used in the management of neonates. Among 82 neonates (mean gestation 30.6 weeks and weight 1375 g) included in the study, 33 (40.2%) received surfactant. The surfactant group had a higher Silverman score, required higher FiO2 and mean airway pressure, and needed invasive ventilation more frequently. The mean (± SD) LUS score was significantly higher in the surfactant (9.4 ± 3.2) compared to the non-surfactant group (5.1 ± 2.1). The diagnostic accuracy of LUS scoring was determined by ROC curve analysis (AUC (95% CI): 0.83 (0.74-0.92), p < 0.01). A cutoff score of ≥ 8 for LUS was considered optimal for the prediction of surfactant requirement (sensitivity and specificity (95% CI) of 70% (51-84) and 80% (66-90), respectively).    Conclusion: Lung ultrasound is a valid diagnostic tool for the prediction of surfactant requirements in resource-limited settings. What is Known: • Lung ultrasound has a good diagnostic accuracy in predicting the need for surfactant administration in preterm neonates in developed countries, but its role in developing countries is unclear. What is New: • Lung ultrasound proved to be a valid diagnostic tool in predicting surfactant replacement therapy in resource-limited settings. • The diagnostic performance of lung ultrasound was better in neonates on non-invasive ventilation, compared to invasive ventilation.

Looking beyond in Sleep Medicine Practice: Effect of OSA Management in Floppy Eyelid Syndrome - A Case Report

Obstructive Sleep Apnea Syndrome (OSA) is a common sleep disorder characterized by recurrent episodes of partial or complete upper airway obstruction during sleep. Floppy Eye Syndrome (FES) is a condition in which the upper eyelids easily evert with upward traction due to underlying tarsal plate laxity and is associated with chronic, reactive papillary conjunctivitis; this causes the eye to be vulnerable to discomfort and visual symptoms. A 49-year-old man with an 8-year history of snoring, sleep fragmentation, and daytime sleepiness was admitted as an outpatient in our sleep clinic. The patient had complied ocular symptoms such as burning eyes, redness, and irritative ocular symptoms in the past five years, arising upon waking up. The symptoms did not regress with the use of artificial tears and proper ointment. The patient was diagnosed with OSA and began using continuous positive airway pressure (CPAP). CPAP therapy significantly corrected the symptoms of FES associated with OSA . This would help to sensibilize ocular findings in patients with OSA and identify hidden sleeping diseases needing a more appropriate investigation and possible treatment. We must look beyond our approach to sleep clinic patients and avoid being kept to the common symptoms patients represent.

Management of Obstructive Sleep Apnea in the Infant and Newborn

Obstructive sleep apnea in newborns and infants presents a unique challenge with distinct differences in sleep physiology, etiologies, and management compared to older children. The indications for and interpretation of polysomnography are less well defined in infants. There are also no broadly accepted clinical practice guidelines for treating sleep apnea in this age group. Etiologies include general causes of upper airway obstruction in infants such as laryngomalacia, micrognathia, and nasal obstruction in addition to adenotonsillar hypertrophy. Treatment strategies must be tailored to the specific anatomic features and comorbidities of the specific patients and often require a multidisciplinary approach.

Obstructive Sleep Apnea, Obesity Hypoventilation Syndrome, and Pulmonary Hypertension: A State-of-the-Art Review

The pathophysiological interplay between sleep-disordered breathing (SDB) and pulmonary hypertension (PH) is complex and can involve a variety of mechanisms by which SDB can worsen PH. These mechanistic pathways include wide swings in intrathoracic pressure while breathing against an occluded upper airway, intermittent and/or sustained hypoxemia, acute and/or chronic hypercapnia, and obesity. In this review, we discuss how the downstream consequences of SDB can adversely impact PH, the challenges in accurately diagnosing and classifying PH in the severely obese, and review the limited literature assessing the effect of treating obesity, obstructive sleep apnea, and obesity hypoventilation syndrome on PH.

Age matters: association between age and depression severity at the time of OSA diagnosis and PAP adherence in adult patients

STUDY OBJECTIVES

Numerous studies have shown an association and symptom overlaps between obstructive sleep apnea (OSA) and depression. However, data are limited on the association between age, sex, the severity of depression at the time of OSA diagnosis, and its impact on positive airway pressure (PAP) adherence. The Patient Health Questionnaire (PHQ-9) is a validated depression screening and severity scoring tool recommended by the Diagnostic and Statistical Manual of Mental Disorders (fifth edition). In this retrospective observational study, we evaluate the interrelationship between age at OSA diagnosis, depression severity, and PAP adherence.

METHODS

Patients with new OSA diagnosis, seen at the University of California San Francisco-Fresno Sleep Center between February and October of 2022, were evaluated. PHQ-9 scores for depression severity uses a 1 to 5 scale (1 = none, 2 = mild, 3 = moderate, 4 moderately severe, 5 = severe). The PHQ-9 was administered at the time of OSA diagnosis and follow-up. Average daily PAP usage hours were obtained from PAP devices between 1 to 3 months after therapy initiation. IBM SPSS version 29.0.0 was used to calculate descriptive statistics, Pearson correlation, and Mann-Whitney test.

RESULTS

Seventy-seven patients fit the inclusion criteria, of which 28 were women (36.4%). The average baseline apnea-hypopnea index was 34.5 (standard deviation 31.8), with a PHQ-9 mean of 8.3 with standard deviation ± 5.9. A Mann-Whitney comparison between the group with normal PHQ-9 scores and the group with PHQ-9 scores consistent with depression (score of 5 or greater) showed no statistically significant differences in apnea-hypopnea index (P = .470) or average night hour use (P = .195). There was a statistically significant difference in age between both groups (P = .031). Spearman correlation confirmed a negative, statistically significant correlation between PHQ-9 scores and age in patients with OSA.

CONCLUSIONS

This study showed that PHQ-9 scores at the time of OSA diagnosis are moderately correlated with younger age, with those patients younger than 50 years old having more moderate to severe depression scores than older patients. We did not find a correlation between age and PAP adherence or between PHQ-9 scores and PAP adherence. Our findings can help identify high-risk depression patients early in the diagnosis of OSA and bring awareness that the young adult population can be particularly vulnerable.

CITATION

Niraula R, Singh A, DelRosso LM, Meghpara S, Keenan L. Age matters: association between age and depression severity at the time of OSA diagnosis and PAP adherence in adult patients. J Clin Sleep Med. 2024;20(6):859-862.

Management of neonates with respiratory distress syndrome in resource-limited settings

In South Africa, prematurity stands as one of the foremost causes of neonatal mortality. A significant proportion of these deaths occur because of respiratory distress syndrome of prematurity. The implementation of non-invasive respiratory support, such as continuous positive airway pressure (CPAP), has demonstrated both safety and efficacy in reducing mortality rates and decreasing the need for mechanical ventilation. Given the absence of blood gas analysers and limited radiological services in many district hospitals, the severity of respiratory distress is often assessed through observation of the infant's work of breathing and the utilisation of bedside scoring systems. Based on the work of breathing, non-invasive therapy can be commenced timeously. While evidence supporting the use of high-flow nasal cannula as a primary treatment for respiratory distress syndrome remains limited, it may be considered as an alternative, provided that CPAP machines are available. The purpose of this article is to advocate the use of non-invasive therapy in low resource-limited settings and describe the indications, contraindications, complications, and application of CPAP therapy. This would benefit healthcare workers, especially in low-care settings and district hospitals.

Assessment and management of continuous positive airway pressure therapy in patient with obstructive sleep apnea

Obstructive sleep apnea (OSA) causes excessive daytime sleepiness, impaired daytime functioning, and an increased risk of cardiovascular diseases. Continuous positive airway pressure (CPAP) is a highly effective therapy for moderate to severe OSA. Although CPAP adherence is commonly assessed using a 4-hthreshold, determining the optimal usage time based on clinical outcomes is crucial. While subjective sleepiness often improves with ≥4 h of CPAP usage, an extended duration (≥6 h) may be necessary to impact objective sleepiness. CPAP demonstrated a modest yet clinically meaningful dose-dependent effect on lowering blood pressure. For patients seeking antihypertensive benefits from CPAP therapy, the goal should extend beyond 4 h of use to maximize the therapeutic impact. Recognizing individual variations in sleep duration and responses to CPAP therapy is essential. The adoption of 'individualized goals for CPAP use,' outlining target times for specific outcomes, should also consider an individual's total sleep duration, including periods without CPAP. The impact of CPAP on clinical outcomes may vary, even with the same duration of CPAP use, depending on the period without CPAP use, particularly during the first or second half of sleep. Patients who remove or initiate CPAP midway or have a low CPAP usage frequency may require different forms of guidance. Tailoring patient education to address CPAP usage patterns may be necessary to enhanced satisfaction, self-efficacy, and adherence to therapy. Management of CPAP treatment should be personalized to meet individual needs and adapted based on specific response patterns for achieving treatment efficacy.

Lung Volume and Ventilation Distribution After Bariatric Surgery-High-Flow Nasal Cannula Versus CPAP

BACKGROUND

Patients with obesity are at increased risk of postoperative pulmonary complications. CPAP has been used successfully to prevent and treat acute respiratory failure, but in many clinical scenarios, high-flow nasal cannula (HFNC) therapy is emerging as a possible alternative. We aimed to compare HFNC and CPAP in a sequential study measuring their effects on gas exchange, lung volumes, and gas distribution within the lungs measured through electrical impedance tomography (EIT).

METHODS

We enrolled 15 subjects undergoing laparoscopic bariatric surgery. Postoperatively they underwent the following oxygen therapy protocol (10 min/step): baseline air-entrainment mask, HFNC at increasing (40, 60, 80, and 100 L/min) and decreasing flows (80, 60, and 40 L/min), washout air-entrainment mask and CPAP (10 cm H2O). Primary outcome was the change in end-expiratory lung impedance (ΔEELI) measured by EIT data processing. Secondary outcomes were changes of global inhomogeneity (GI) index and tidal impedance variation (TIV) measured by EIT, arterial oxygenation, carbon dioxide content, pH, respiratory frequency, and subject's comfort.

RESULTS

Thirteen subjects completed the study. Compared to baseline, ΔEELI was higher during 10 cm H2O CPAP (P = .001) and HFNC 100 L/min (P = .02), as well as during decreasing flows HFNC 80, 60, and 40 L/min (P = .008, .004, and .02, respectively). GI index was lower during HFNC 100 compared to HFNC 60increasing (P = .044), HFNC 60decreasing (P = .02) HFNC 40decreasing (P = .01), and during 10 cm H2O CPAP compared to washout period (P = .01) and HFNC 40decreasing (P = .03). TIV was higher during 10 cm H2O CPAP compared to baseline (P = .008). Compared to baseline, breathing frequency was lower at HFNC 60increasing, HFNC 100, and HFNC 80decreasing (P = .01, .02, and .03, respectively). No differences were detected regarding arterial oxygenation, carbon dioxide content, pH, and subject's comfort.

CONCLUSIONS

HFNC at a flow of 100 L/min induced postoperative pulmonary recruitment in bariatric subjects, with no significant differences compared to 10 cm H2O CPAP in terms of lung recruitment and ventilation distribution.

Follow-up assessment of sleep-related symptoms in patients after treatment for cancer: responses to continuous positive airway pressure treatment for co-morbid obstructive sleep apnoea

PURPOSE

To assess changes in sleep-related symptoms in patients with breast cancer, endometrial cancer and melanoma previously examined for sleep-related symptoms and the presence of PSG (polysomnography)-determined OSA, ≥ 3 years post-treatment; and to evaluate how CPAP treatment affects sleep-related symptoms in patients previously diagnosed with OSA.

METHODS

Patients initially recruited from breast cancer, endometrial cancer, and melanoma follow-up clinics at Westmead Hospital (Sydney, Australia) participated in this questionnaire-based study. Demographic and change in cancer status data were collected at follow-up. Patients completed the Pittsburgh Sleep Quality Index [poor sleep quality, PSQITOTAL ≥ 5au], Insomnia Severity Index, Epworth Sleepiness Scale and Functional Outcomes of Sleep Questionnaire; with ΔPSQITOTAL ≥ 3au indicating a clinically meaningful change in sleep quality over follow-up. PSG-determined OSA was confirmed using the apnoea-hypopnoea index. CPAP compliance was determined via self-report (CPAP compliant, CPAP; not compliant, non-CPAP). Logistic regression models determined if changes in cancer status, AHI, cancer subgroup or CPAP treatment was predictive of ΔPSQITOTAL ≥ 3 au and p < 0.05 indicated statistical significance.

RESULTS

The 60 patients recruited had breast cancer (n = 22), endometrial cancer (n = 15), and melanoma (n = 23). Cancer subgroups were similarly aged, and all had median follow-up PSQITOTAL scores ≥ 5au; breast cancer patients scoring the highest (p < 0.05). The CPAP group had significantly reduced PSQITOTAL scores (p = 0.02) at follow-up, unlike the non-CPAP group. Cancer subgroups had similar median ISITOTAL, ESSTOTAL and FOSQ-10TOTAL scores at follow-up, regardless of CPAP treatment. There were no significant predictors of ΔPSQITOTAL ≥ 3 au at follow-up.

CONCLUSION

Sleep-related symptoms persist in patients with cancer ≥ 3 years after treatment, although these symptoms improve with CPAP. Future studies should evaluate how CPAP affects survival outcomes in cancer patients with comorbid OSA.

Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea in a Patient with Cerebral Palsy

INTRODUCTION

Obstructive sleep apnea (OSA) is common amongst patients with cerebral palsy in part due to significant hypotonia. Hypoglossal nerve stimulation (HGNS) is a novel tool used to treat sleep apnea when there is failure with CPAP. To our knowledge, the literature has not discussed HGNS as a treatment option for severe OSA in patients with cerebral palsy.

METHODS

Case report and literature review.

RESULTS

A 28-year-old male with cerebral palsy, neuromuscular deformity, proximal junction kyphosis, and developmental delay presented with severe obstructive sleep apnea and was intolerant to CPAP and BiPAP. After HGNS implantation, a sleep study revealed improved ventilation and oxygenation at 2.4 V; AHI decreased from baseline of 112 to 12 events per hour with only mild intermittent snoring. The patient's family reported increased utilization compared with previous CPAP use.

CONCLUSION

HGNS can be a safe and effective treatment modality for OSA in this patient population. Laryngoscope, 134:2478-2479, 2024.

Sleep apnea, the risk of out-of-hospital cardiac arrest, and potential benefits of continuous positive airway pressure therapy: A nationwide study

OBJECTIVE

Patients with sleep apnea (SA) are at increased cardiovascular risk. However, little is known about the risk of out-of-hospital cardiac arrest (OHCA) in patients with SA. Therefore, we studied the relation between SA patients who did and did not receive continuous positive airway pressure (CPAP) therapy with OHCA in the general population.

METHODS

Using nationwide databases, we conducted a nested case-control study with OHCA-cases of presumed cardiac causes and age/sex/OHCA-date matched non-OHCA-controls from the general population. Conditional logistic regression models with adjustments for well-known OHCA risk factors were performed to generate odds ratio (OR) of OHCA comparing patients with SA receiving and not receiving CPAP therapy with individuals without SA.

RESULTS

We identified 46,578 OHCA-cases and 232,890 matched non-OHCA-controls [mean: 71 years, 68.8% men]. Compared to subjects without SA, having SA without CPAP therapy was associated with increased odds of OHCA after controlling for relevant confounders (OR:1.20, 95%-Cl:1.06-1.36), while having SA with CPAP therapy was not associated with OHCA (OR:1.04, 95%-Cl:0.93-1.36). Regardless of CPAP therapy, age and sex did not significantly influence our findings. Our findings were confirmed in: (I) patients with neither ischemic heart disease nor heart failure (untreated SA, OR:1.24, 95%-CI:1.04-1.47; SA with CPAP, OR:1.08, 95%-CI:0.93-1.25); and (II) in patients without cardiovascular disease (untreated SA, OR:1.33, 95%-CI:1.07-1.65; SA with CPAP, OR:1.14, 95%-CI:0.94-1.39).

CONCLUSION

SA not treated with CPAP was associated with OHCA, while no increased risk of OHCA was found for SA patients treated with CPAP.

Customized Silicone Foam Dressing Under Noninvasive Ventilation and Skincare Bundle to Reduce Hospital-Acquired Pressure Injuries in Neonates

In a sixty-eight-bed level-IV NICU, an increased incidence of hospital-acquired pressure injuries (HAPIs) from noninvasive ventilation (NIV) devices was identified. The aim of this quality improvement project was to decrease HAPIs from NIV by 10%. A literature review and the Plan-Do-Study-Act were implemented. The intervention included a customized silicone foam dressing under NIV, an NIV skincare bundle, and multidisciplinary support. Hospital-acquired pressure injury rates were tracked over 3 years postinterventions. The incidence of HAPIs declined by 20% from 0.2 per 1,000 patient days to 0.05 per 1,000 patient days. Relative risk was 4.6 times greater prior to intervention (p = .04). Continuous positive airway pressure (CPAP) failure was not noted and measured by the percentage of patients on ventilators pre- and postintervention. Customized silicone foam dressings under NIV, NIV skincare bundle, and multidisciplinary team support may decrease HAPIs in neonates without CPAP failure.

Long-term pneumatic stenting with positive expiratory pressure therapy for severe expiratory central airway collapse

Expiratory central airway collapse (ECAC) comprising excessive central airway collapse (EDAC) and tracheobronchomalacia. Treatment is challenging for severe cases that are not candidates for surgical management. We report a case of severe ECAC successfully managed with continuous positive airway pressure (CPAP) therapy. A 75-year-old female patient status post right pneumonectomy, presented with chronic cough. Dynamic bronchoscopy evaluation showed severe EDAC which improved with intraprocedural noninvasive positive pressure (NIPPV) therapy. Due to patients' comorbidities, she was not a candidate to surgical tracheobronchoplasty. Therefore, we attempted pneumatic stenting with long-term CPAP therapy resulting in improvement of symptoms and functional capacity. The long-term efficacy of pneumatic stenting has not been clearly established yet. Literature review of management of ECAC with NIPPV consist primarily of case reports and there is only one clinical trial being conducted to assess the efficacy of CPAP therapy in ECAC. While NIPPV arises as a sufficient alternative for management of severe ECAC, larger scale studies are needed to prove the real efficacy of NIPPV in this setting.

The Effect of Continuous Positive Airway Pressure (CPAP) Therapy on Serum Caspase-3 Level in Patients with Obstructive Sleep Apnea (OSA)

INTRODUCTION

Intermittent hypoxemia has an important role in the physiopathogenesis of obstructive sleep apnea (OSA) complications. Increased apoptosis due to intermittent hypoxemia may be an important clinical entity in OSA. In this study, we aimed to evaluate caspase-3 enzyme level, which is an indirect marker of increased apoptosis in patients with OSA and to evaluate the effect of OSA treatment with continuous positive airway pressure on caspase-3 enzyme level.

MATERIALS AND METHODS

This study included 141 consecutive patients admitted to the sleep-disordered breathing laboratory within 6 months. Caspase-3 was measured in routine blood samples obtained on the morning of polysomnography (PSG) performed at night. The compliance of the patients to CPAP treatment was evaluated and caspase-3 levels were checked again after treatment.

RESULTS

A total of 141 patients, 39 females (27,7%) and 102 males (72,3%) were included in the study. The mean age of the patients was 49 ± 12 years (min-17, max-77). According to PSG results, OSA was detected in 95.7% (135/141) of the cases. Mild OSA was 35 (24.8%), moderate OSA 39 (27.7%) and severe OSA 61 (43.3%) cases. Median caspase-3 enzyme levels were similar in men and women in the study group. There was no statistically significant difference in hemogram parameters and caspase-3 enzyme levels between the groups divided according to the presence and severity of OSA. It was determined that caspase-3 enzyme level did not change significantly after 3 months of CPAP treatment in OSA compared to pretreatment. Caspase-3 was found to have a negative correlation with both the percentage of daily use of CPAP therapy and the percentage of CPAP device use for more than 1 h per night. It was found that the control caspase-3 level decreased statistically significantly as the percentage of daily use of CPAP therapy increased (r = -0.397, p = 0.030). It was found that the control caspase-3 level decreased statistically significantly as the percentage of CPAP therapy use for more than 1 h per night increased (r = -0.411, p = 0.024).

CONCLUSION

The results of this study did not reveal a relationship between the severity of OSA and caspase-3 levels. However, blood caspase-3 levels decreased as treatment compliance increased, suggesting that CPAP treatment may correct increased apoptosis in OSA. There is a need for more comprehensive studies on this issue.

Impacts of conservative treatment on the clinical manifestations of obstructive sleep apnea-systematic review and meta-analysis

INTRODUCTION

Obstructive sleep apnea (OSA) is a chronic disease with a high populational prevalence that is characterized as airway closure during sleep. Treatment is multidisciplinary and varies according to each case. Continuous positive airway pressure (CPAP), oral appliances, and surgery are the primary therapeutic options. Non-invasive conservative treatments such as sleep hygiene, positional therapy, physical exercises, and weight loss aim to reduce the worsening of the disease while being complementary to the invasive primary treatment.

OBJECTIVE

To analyze the impact of non-invasive conservative therapies on the clinical manifestations of OSA syndrome (OSA), compared with other interventions.

METHOD

This was a systematic review with meta-analysis. The searches were performed without filters for the time period, type of publication, or language. Randomized clinical trials on subjects over 18 years of age diagnosed with untreated OSA were included. Responses to non-invasive conservative treatment were compared with responses to the primary intervention. Primary outcomes were assessed using the Epworth Sleepiness Scale and/or Functional Outcomes of Sleep Questionnaire (FOSQ).

RESULTS

A total of eight studies were included in the review. The heterogeneity of the effect was estimated at 89.77%. Six studies compared conservative treatment with CPAP, one with oral appliances, and one with oropharyngeal exercises. Using the Epworth Sleepiness Scale measurements, the standardized difference in the estimated means, based on the random-effects model, was 0.457 (95% CI (1.082 to 0.169)) and the mean result did not differ significantly from zero (z = 1.43; p = 0.153). The conservative therapies assessed in this study improved the subjective quality of sleep, although the post-treatment ESE scores did not show significant results. The reduction in AHI and better outcomes in the evaluated domains, as well as in cognition and mood, were superior in the groups that received CPAP and IOD.

CONCLUSION

The most commonly used treatments of choice for OSA are invasive, including the use of CPAP, oral appliances, and surgeries, being the most utilized options. This study demonstrated that non-invasive conservative treatments, such as sleep hygiene, yield results as effective as invasive treatments. Further studies are needed to confirm this result and to predict whether invasive treatment can be used as the primary treatment or only as a supplement.

"Every breath you take": evaluating sound levels and acoustic characteristics of various neonatal respiratory support and ventilation modalities

Background

Early sensory experiences have a significant impact on the later life of preterm infants. The NICU soundscape is profoundly influenced by various modalities of respiratory support or ventilation, which are often mandatory early in the care. The incubator, believed to shield from external noise, is less effective against noise originating inside. The objective of this study was to evaluate the sound levels and characteristics of frequently used respiratory support and ventilation modalities, taking into consideration the developing auditory system of premature infants.

Methods

To evaluate sound dynamics inside and outside an incubator during respiratory support/ventilation, experimental recordings were conducted at the Center for Pediatric Simulation Training of the Medical University Vienna. The ventilator used was a FABIAN HFOI®.

Results

Jet CPAP (Continuous positive airway pressure), whether administered via mask or prongs, generates significantly higher sound levels compared to High-flow nasal cannula (HFNC) and to High-frequency oscillatory ventilation (HFOV) delivered through an endotracheal tube. Upon evaluating the sound spectrum of jet CPAP support, a spectral peak is observed within the frequency range of 4 to 8 kHz. Notably, this frequency band aligns with the range where the hearing threshold of preterm infants is at its most sensitive.

Conclusion

Non-invasive HFNC and invasive HFOV generate lower sound levels compared to those produced by jet CPAP systems delivered via masks or prongs. Moreover, HFNC and HFOV show a reduced acoustic presence within the frequency range where the preterm infant's hearing is highly sensitive. Therefore, it is reasonable to speculate that the potential for auditory impairment might be more pronounced in preterm infants who require prolonged use of jet CPAP therapy during their time in the incubator.

Potential Therapeutic Targets in Obesity, Sleep Apnea, Diabetes, and Fatty Liver Disease

Obesity and metabolic syndrome affect the majority of the US population. Patients with obesity are at increased risk of developing type 2 diabetes (T2DM), obstructive sleep apnea (OSA), and metabolic dysfunction-associated steatotic liver disease (MASLD), each of which carry the risk of further complications if left untreated and lead to adverse outcomes. The rising prevalence of obesity and its comorbidities has led to increased mortality, decreased quality of life, and rising healthcare expenditures. This phenomenon has resulted in the intensive investigation of exciting therapies for obesity over the past decade, including more treatments that are still in the pipeline. In our present report, we aim to solidify the relationships among obesity, T2DM, OSA, and MASLD through a comprehensive review of current research. We also provide an overview of the surgical and pharmacologic treatment classes that target these relationships, namely bariatric surgery, the glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon receptor agonists.

Method for evaluating the fit of custom-fit Continuous Positive Airway Pressure masks using finite element analysis

Continuous Positive Airway Pressure (CPAP) is a common therapy used to treat breathing disorders such as obstructive sleep apnea. In previous work, we designed a custom-fit CPAP mask to address comfort and leakage issues patients often experience. This paper presents a method to create a finite element (FE) model to evaluate the fit of the custom-fit mask before fabrication. The model includes details such as a skull to represent the variable soft tissue thicknesses on the face, and two strap configurations, original and X. The model was tested on four subjects and results show that the X strap configuration results in a more even stress distribution, measured by standard deviation, on the face compared to the original strap, indicating better fit. The simulations also show gaps in the stress distribution that seem to correspond to areas of leakage based on two initial in vivo tests on two subjects. This simulation method proves to be a valuable tool for custom-fit mask development by allowing us to evaluate designs before fabrication.

Obstructive Sleep Apnea and Stroke: Determining the Mechanisms Behind their Association and Treatment Options

Sleep-disordered breathing (SDB) can be a sequela of stroke caused by vascular injury to vital respiratory centers, cerebral edema, and increased intracranial pressure of space-occupying lesions. Likewise, obstructive sleep apnea (OSA) contributes to increased stroke risk through local mechanisms such as impaired ischemic cerebrovascular response and systemic effects such as promoting atherosclerosis, hypercoagulability, cardiac arrhythmias, vascular-endothelial dysfunction, and metabolic syndrome. The impact of OSA on stroke outcomes has been established, yet it receives less attention in national guidelines on stroke management than hyperglycemia and blood pressure dysregulation. Furthermore, whether untreated OSA worsens stroke outcomes is not well-described in the literature. This scoping review provides an updated investigation of the correlation between OSA and stroke, including inter-relational pathophysiology. This review also highlights the importance of OSA treatment and its role in stroke outcomes. Knowledge of pathophysiology, the inter-relationship between these common disorders, and the impact of OSA therapy on outcomes affect the clinical management of patients with acute ischemic stroke. In addition, understanding the relationship between stroke outcomes and pre-existing OSA will allow clinicians to predict outcomes while treating acute stroke.

The "ZEEP-PEEP test" to evaluate the response to positive end-expiratory pressure delivered by helmet: A prospective physiologic study

Introduction

The improvement in oxygenation after helmet application in hypoxemic patients may be explained by the alveolar recruitment obtained with positive end expiratory pressure (PEEP) or by the administration of a more accurate inspiratory fraction of oxygen (FiO2). We have designed the "ZEEP-PEEP test", capable to distinguish between the FiO2-related or PEEP-related oxygenation improvement. Our primary aim was to describe the use of this test during helmet CPAP to assess the oxygenation improvement attributable to PEEP application.

Material and methods

We performed a prospective physiological study including adult critically ill patients. Respiratory and hemodynamic parameters were recorded before helmet application (PRE step), after helmet application without PEEP (ZEEP step) and after the application of the PEEP valve (PEEP step), while maintaining a constant FiO2. We defined as "PEEP responders" patients showing a PaO2/FiO2 ratio improvement ≥10% after PEEP application.

Results

93 patients were enrolled. Compared to the PRE step, PaO2/FiO2 ratio was significantly improved during helmet CPAP both at ZEEP and PEEP step (189 ± 55, 219 ± 74 and 241 ± 82 mmHg, respectively, p < 0.01). Both PEEP responders (41%) and non-responders showed a significant improvement of PaO2/FiO2 ratio after the application of helmet at ZEEP, PEEP responders also showed a significant improvement of oxygenation after PEEP application (208 ± 70 vs 267 ± 85, p < 0.01).

Conclusions

Helmet CPAP improved oxygenation. This improvement was not only due to the PEEP effect, but also to the increase of the effective inspired FiO2. Performing the ZEEP-PEEP test may help to identify patients who benefit from PEEP.

Distance follow-up by a remote medical care centre improves adherence to CPAP in patients with obstructive sleep apnoea over the short and long term

BACKGROUND

Adherence to continuous positive air pressure (CPAP) in patients with obstructive sleep apnoea (OSA) has remained invariably low over the last decades. Remote monitoring of the nocturnal CPAP treatment, within telemedicine (TM)-based follow-up programs, in these patients has been suggested as a potential tool to improve adherence and release the workload of sleep units. The aim of this study was therefore to assess whether a follow-up program carried out by a Remote Medical Care Centre (RMCC), outside the sleep unit, improves adherence to CPAP in the short and long term in patients with OSA.

METHODS

In this pilot protocol, we enrolled 37 patients starting CPAP in our Sleep Centre (SC). After three months of standard care in our SC, patients initiated a six-month remote follow-up carried out by the RMCC, functioning as an intermediary between patients and SC. Monthly reports and indication for face-to-face visits were sent to the SC for six months. After this period patients returned to usual care for one year. Results were compared with those obtained in 38 patients (controls) followed with usual care over the same time range.

RESULTS

Mean nightly use of CPAP increased from 3.2 ± 2.4 h pre-RMCC to 5.2 ± 1.9 h post-RMCC (p < 0.0001). Nights/month of CPAP use improved from 19.8 ± 9.2 to 25.2 ± 2.5 (p < 0.05) and nights/month with CPAP use >4 h from 12.5 ± 10 to 21.03 ± 8.9 (p < 0.05). This improvement remained stable after 12 months from the return of patients to usual care. No significant changes in CPAP use were observed in controls over the time.

CONCLUSION

A six-month follow-up through a remote facility can significantly improve adherence to CPAP in the short and long term. This pilot study provides a solid base for the design of multicentre randomized trials focusing on new models which are able to increase the long-term efficacy of TM programs.

Awake pronation with helmet CPAP in early COVID-19 ARDS patients: effects on respiratory effort and distribution of ventilation assessed by EIT

Prone positioning with continuous positive airway pressure (CPAP) is widely used for respiratory support in awake patients with COVID-19-associated acute respiratory failure. We aimed to assess the respiratory mechanics and distribution of ventilation in COVID-19-associated ARDS treated by CPAP in awake prone position. We studied 16 awake COVID-19 patients with moderate-to-severe ARDS. The study protocol consisted of a randomized sequence of supine and prone position with imposed positive end-expiratory pressure (PEEP) of 5 and 10 cmH2O delivered by helmet CPAP. Respiratory mechanics and distribution of ventilation were assessed through esophageal pressure (PES) and electrical impedance tomography (EIT). At the end of each 20-min phase, arterial blood gas analysis was performed, and PES swing and EIT tracings were recorded for the calculation of the respiratory mechanics and regional ventilation. The patient's position had no significant effects on respiratory mechanics. EIT analysis did not detect differences among global indices of ventilation. A significant proportion of pixels in the sternal region of interest showed an increase in compliance from the supine to prone position and PaO2/FIO2 increased accordingly. The best improvement of both PaO2/FIO2 and sternal compliance was obtained in the prone position with PEEP 10 cmH2O. In the studied subjects, prone positioning during CPAP treatment raised oxygenation without improvement of "protective" ventilation or global ventilatory inhomogeneity indices. Prone positioning with higher PEEP significantly increased the compliance of sternal regions.

Carrara V, Meeyai A, Aderoba AK, Nosten F, Gross MM, McGready R. Antenatal corticosteroids reduce neonatal mortality in settings without assisted ventilatory support: a retrospective cohort study of early preterm births on the Thailand-Myanmar border

Background

Prematurity is the highest risk for under-five mortality globally. The aim of the study was to assess the effect of antenatal dexamethasone on neonatal mortality in early preterm in a resource-constrained setting without assisted ventilation.

Methods

This retrospective (2008-2013) cohort study in clinics for refugees/migrants on the Thai-Myanmar border included infants born <34 weeks gestation at home, in, or on the way to the clinic. Dexamethasone, 24 mg (three 8 mg intramuscular doses, every 8 hours), was prescribed to women at risk of preterm birth (28 to <34 weeks). Appropriate newborn care was available: including oxygen but not assisted ventilation. Mortality and maternal fever were compared by the number of doses (complete: three, incomplete (one or two), or no dose). A sub-cohort participated in neurodevelopmental testing at one year.

Results

Of 15,285 singleton births, 240 were included: 96 did not receive dexamethasone and 144 received one, two or three doses (56, 13 and 75, respectively). Of live-born infants followed to day 28, (n=168), early neonatal and neonatal mortality/1,000 livebirths (95%CI) with complete dosing was 217 (121-358) and 304 (190-449); compared to 394 (289-511) and 521 (407-633) with no dose. Compared to complete dosing, both incomplete and no dexamethasone were associated with elevated adjusted ORs 4.09 (1.39 to 12.00) and 3.13 (1.14 to 8.63), for early neonatal death. By contrast, for neonatal death, while there was clear evidence that no dosing was associated with higher mortality, adjusted OR 3.82 (1.42 to 10.27), the benefit of incomplete dosing was uncertain adjusted OR 1.75 (0.63 to 4.81). No adverse impact of dexamethasone on infant neurodevelopmental scores (12 months) or maternal fever was observed.

Conclusions

Neonatal mortality reduction is possible with complete dexamethasone dosing in pregnancies at risk of preterm birth in settings without capacity to provide assisted ventilation.

Multisystem approach for management of OSA in Down syndrome: a case report

Obstructive sleep apnea (OSA) is common in children with Down syndrome, with reported prevalence rates as high as 69-76%. Multiple factors predispose children with Down syndrome for OSA, including craniofacial hypoplasia (maxillary and mandibular), airway abnormalities, macroglossia, generalized hypotonia, airway hypotonia, adenotonsillar hypertrophy, and obesity. Despite the fact that the pathophysiology for OSA in children with Down syndrome is multifactorial in nature, treatment methods have focused on soft tissue in the upper airway using adenotonsillectomy and/or continuous positive airway pressure therapy. Here we present a case of a patient with Down syndrome whose severe OSA was approached in a multisystem manner, including upper airway soft tissue, orthognathic, maxillofacial, and bariatric surgery, resulting in resolution of the OSA without reliance on a continuous positive airway pressure device.

CITATION

Finch CE, Raol N, Roser SM, Leu RM. Multisystem approach for management of OSA in Down syndrome: a case report. J Clin Sleep Med. 2024;20(3):471-473.