Use of average volume-assured pressure support as a therapeutic option in patients with central sleep apnea syndrome.

PURPOSE: Central sleep apnea (CSA) syndrome commonly occurs with other medical conditions such as congestive heart failure, opiate use, and brainstem disorders. Various treatment modalities have been used with varied effectiveness in an attempt to improve ventilation and reduce the apnea-hypopnea index (AHI) in patients with CSA. This study evaluated whether or not a bilevel positive airway pressure mode of noninvasive ventilation, average volume-assured pressure support (AVAPS) is effective in treating CSA. METHODS: This was a retrospective review of patients with CSA who underwent AVAPS titration studies at our institution. We included patients with CSA with apnea-hypopnea index (events/hour) (AHI) ≥ 15, and examined the effectiveness of AVAPS in reducing AHI, improving oxygenation parameters, and improving sleep architecture. RESULTS: There were 12 patients, with mean age 62.8 ± 11.5 years, body mass index (BMI) 33.5 ± 4.7 kg/m2, 8 men, and Epworth Sleepiness Scale 9.3 ± 4.9. Five patients had CSA attributed to opiate use, 4 patients had CSA with Cheyne-Stokes respiration, and 3 patients had primary CSA. The only significant change from baseline PSG was AHI reduction with AVAPS: 63.3 ± 19.1 to 30.5 ± 30.3 (p < 0.003). In 5 patients (42%), AHI was reduced to < 15 with AVAPS use. Improvement in AHI was not related to gender, BMI, opiate use, or age. Defining response to therapy as AHI reduced to < 15, we found that lack of hypertension was the only significant predictor of response (p = 0.045). No significant changes in sleep architecture between the two studies were found. CONCLUSION: AVAPS is an effective mode of treating CSA in a significant proportion of patients. More studies are needed to confirm these findings and determine what factors are associated with response to therapy.

Invasive mechanical ventilation using a bilevel PAP ST device in a healthy swine model.

PURPOSE: The Coronavirus Disease 2019 (COVID-19) pandemic may cause an acute shortage of ventilators. Standard noninvasive bilevel positive airway pressure devices with spontaneous and timed respirations (bilevel PAP ST) could provide invasive ventilation but evidence on their effectiveness in this capacity is limited. We sought to evaluate the ability of bilevel PAP ST to effect gas exchange via invasive ventilation in a healthy swine model. METHODS: Two single limb respiratory circuits with passive filtered exhalation were constructed and evaluated. Next, two bilevel PAP ST devices, designed for sleep laboratory and home use, were tested on an intubated healthy swine model using these circuits. These devices were compared to an anesthesia ventilator. RESULTS: We evaluated respiratory mechanics, minute ventilation, oxygenation, and presence of rebreathing for all of these devices. Both bilevel PAP ST devices were able to control the measured parameters. There were noted differences in performance between the two devices. Despite these differences, both devices provided effective invasive ventilation by controlling minute ventilation and providing adequate oxygenation in the animal model. CONCLUSIONS: Commercially available bilevel PAP ST can provide invasive ventilation with a single limb respiratory circuit and in-line filters to control oxygenation and ventilation without significant rebreathing in a swine model. Further study is needed to evaluate safety and efficacy in clinical disease models. In the setting of a ventilator shortage during the COVID-19 pandemic, and in other resource-constrained situations, these devices may be considered as an effective alternative means for invasive ventilation.

Gait-speed and oxygen flow during six-minute walk test predicts mortality in patients with advanced lung disease.

The six-minute walk test (6MWT) is a useful tool to predict outcomes in patients with advanced lung diseases. Greater distance walked has been shown to have more favorable prognostic value compared to other recorded variables.  We reviewed the medical records of 164 patients with advanced lung disease who underwent lung transplant evaluation. Results of the 6MWT (distance walked, oxygen required, and mean gait speed) were recorded and analyzed with respect to mortality. 6MWT mean oxygen (O2) flow via nasal cannula was 3.5 ± 3.7 L/min. The distance walked in meters (m) and % predicted were inversely associated with mortality, OR: 0.995 (0.992-0.998) and 0.970 (0.950-0.990), respectively. Patients who walked < 200 meters (OR: 2.1 (1.1-4.0)) or < 45% of predicted, OR: 2.7 (1.2-5.7) had higher mortality. O2 flow during the test had a direct association with mortality (OR: 1.1 (1.0-1.2). In multivariate analysis, O2 flow > 3.5 L/min remained predictive of mortality, OR: 1.1 (1.0-1.2). Mean gait speed was higher in patient who lived compared with patients who died (mean 0.83 ± 0.35 m/mim vs mean 0.69 ± 0.33 m/min, respectively, p= 0.03). Gait speed was a predictor of survival, OR 3.4 (1.1, 10.6). O2 flow during the 6MWT was an independent predictor of mortality in patients with advanced lung disease. The patients that required more than 3.5 L/m of O2 had a higher mortality. Faster gait speed during the 6MWT was also associated with better survival.

The utility of current criteria for split-night polysomnography for predicting CPAP eligibility.

INTRODUCTION: Traditionally, evaluation of obstructive sleep apnea (OSA) has consisted of a diagnostic polysomnogram (PSG), followed by a continuous positive pressure (CPAP) titration. However, to reduce costs, many third-party payers mandate performance of split-night studies (SPL), combining diagnostic and CPAP titration testing. We ascertained the utility of performing SPL for diagnosis and treatment of OSA. METHODS: We reviewed the PSG records of 200 patients suspected of having OSA. Using both American Academy of Sleep Medicine (AASM) and Medicare (CMS) criteria for scoring, we calculated the sensitivity, specificity, positive (PPV), and negative predictive value (NPV) of the AHI in the first 2 h of sleep for predicting an overall AHI > 15. RESULTS: For predicting an overall AHI > 15, the sensitivity, specificity, PPV, and NPV of an AHI (AASM criteria) > 40 in the first 2 h were respectively: 0.304, 1.000, 1.000, and 0.335. For an AHI > 20 in the first 2 h, the corresponding values were 0.770, 0.962, 0.983, and 0.595. Corresponding values using CMS criteria were 0.347, 1.0, 1.0, and 0.6 for AHI > 40, and 0.693, 0.99, 0.986, and 0.76 for AHI > 20, respectively. CONCLUSION: For justification of CPAP (overall AHI > 15), the sensitivity is slightly lower when using an AHI > 40 vs AHI > 20, but the specificity and PPV are much higher. Using AHI > 20 as criteria for SPL as opposed to the guideline criteria of AHI > 40 may be more effective in obtaining CPAP for patients with moderate to severe OSA.

Acute eosinophilic pneumonia triggered by secondhand cigarette smoke exposure in an elderly man.

The spectrum of eosinophilic lung diseases comprises a diverse group of pulmonary disorders associated with tissue or peripheral eosinophilia. [Acute eosinophilic pneumonia (AEP)] is an uncommon eosinophilic lung disease that can be idiopathic, but identifiable causes include medications, inhalational exposures and infections. Most cases in the literature are associated with first-time cigarette smoking or resuming smoking. Herein, we present a case of AEP in an elderly man triggered by exposure to secondhand tobacco smoke, in whom a transbronchial biopsy was diagnostic. The patient recovered fully with glucocorticoid therapy without recurrence after avoiding further secondhand smoke.

Comparison of American Academy of Sleep Medicine (AASM) versus Center for Medicare and Medicaid Services (CMS) polysomnography (PSG) scoring rules on AHI and eligibility for continuous positive airway pressure (CPAP) treatment.

BACKGROUND: Obstructive sleep apnea (OSA) is an important clinical condition. Eligibility for treatment usually depends on disease severity, measured as the apnea-hypopnea index (AHI), equal to the sum of apneas plus hypopneas per hour of sleep. There is divergence on scoring rules for hypopneas between the recommendations of the American Academy of Sleep Medicine (AASM) and the Center for Medicare Services (CMS), the latter being more restrictive. Thus, patients could be eligible for treatment under AASM rules, but not under CMS rules. METHODS: Sleep laboratory records of 112 consecutive patients were reviewed (85 < 65, 27 ≥ 65 years old). AHI was calculated both by AASM and by CMS criteria. Information on demographics, and important comorbidities, was also reviewed. RESULTS: AHI was lower in younger patients using CMS criteria. However, differences in AHI using the two sets of criteria were not significantly different in the older patients. Incorporating all criteria for eligibility (severity, presence of certain comorbid conditions) for treatment, we found that fewer younger patients would be eligible using CMS criteria, but among the older patients, eligibility for treatment was the same whether AASM or CMS criteria were used. CONCLUSIONS: Use of CMS criteria for scoring hypopneas results in lower estimates of OSA severity, with fewer younger patients eligible for treatment. However, among Medicare age patients, the rate of treatment eligibility was the same whether AASM or CMS scoring rules were used.

Comparison of a simple obstructive sleep apnea screening device with standard in-laboratory polysomnography.

BACKGROUND: Obstructive sleep apnea (OSA) is a common underdiagnosed sleep disorder. Various strategies have been employed to easily screen for OSA. The ApneaStrip® (AS - S.L.P. Ltd, Tel Aviv, Israel) is an FDA approved OSA screening device applied to the upper lip at home. We evaluated the performance of this device against simultaneous in-laboratory polysomnography (PSG) in a group of well-characterized OSA patients. METHODS: Diagnostic PSG was performed in 56 patients (29 M, 37 F; age 48.9 ± 14.6 years; body mass index [BMI] 37.5 ± 9.0 kg/m(2); apnea-hypopnea index-events/h-[AHI] 32.8 ± 22.9). The AS was applied and positioned to detect nasal and oral airflow. The AS gives a "positive" result for AHI ≥ 15. We examined the sensitivity and specificity of the AS against three thresholds derived from PSG: AHI ≥ 5, AHI ≥ 15 (company recommendation), and AHI ≥ 30. RESULTS: For PSG AHI ≥ 15, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the AS were 80, 54.5, 87.8, and 40 %, respectively. For PSG AHI ≥ 5, the values were 75.1, 66.7, 97.1, and 13.3 %, respectively. For PSG AHI ≥ 30, the values were 86.9, 36.2, 48.8, and 80 %, respectively. There were no significant modifying effects of age, BMI, gender, hypertension, diabetes, lung disease, and heart disease. CONCLUSION: The AS has a high sensitivity for detection of OSA with AHI ≥ 15, but only modest specificity. The AS could be a useful component of an OSA screening program; however, negative results should be interpreted cautiously.

Successful Treatment of Respiratory Failure in a Patient with Prader-Willi Syndrome with Noninvasive Ventilation with AVAPS.

Prader-Willi syndrome (PWS) is the most prevalent syndromic form of obesity, which starts during early childhood in the setting of hyperphagia. Due to the development of obesity, there is a high prevalence of obstructive sleep apnea (OSA) among these patients. This case report presents a patient with PWS with morbid obesity, severe OSA, and obesity hypoventilation syndrome admitted to the hospital for hypoxemic and hypercapnic respiratory failure. Noninvasive ventilation (NIV) with average volume-assured pressure support, a newer NIV modality, was used successfully to treat this patient, achieving major clinical and gas exchange improvement both during the hospitalization and long term after discharge.

Average Volume-assured Pressure Support as Rescue Therapy after CPAP Failure in Pediatric Obstructive Sleep Apnea: A Retrospective Case Series Study.

Background: Continuous positive airway pressure (CPAP) is frequently prescribed for patients with residual obstructive sleep apnea (OSA) following adenotonsillectomy. Objectives: The goal was to examine the efficacy of noninvasive ventilation with average volume-assured pressure support (AVAPS) as a potential option for children with failed CPAP titration. Methods: In a single-center retrospective study, we included children aged 1-17 years, with polysomnographically confirmed OSA who underwent AVAPS titration following failed CPAP titration. In addition to describing the clinical characteristics of the included patients, we compared polysomnographic parameters before and after AVAPS. Results: Nine patients met the inclusion criteria; out of them, 8 (89%) were males with an age range of 6.7 ± 3.9 years and a body mass index percentile of 81.0 ± 28.9. Reasons for failed CPAP titration were: 3 (33%) patients due to inability to control apnea-hypopnea index (AHI), 3 (33%) patients due to sleep-related hypoventilation, 2 (22%) patients due to treatment-emergent central sleep apnea, and 1 (11%) patient due to intolerance to CPAP. AVAPS resulted in a greater reduction in AHI than CPAP (reduction following CPAP = 24.6 ± 29.3, reduction following AVAPS = 42.5 ± 37.6, p = 0.008). All patients had resolution of the problems which caused CPAP failure. Conclusion: In this case a series of children with OSA and with failed CPAP titration, AVAPS resulted in a greater reduction in AHI compared with CPAP as well as resolution of the problems which caused CPAP failure.

Sleep-disordered breathing may be under-recognized in patients who wean from prolonged mechanical ventilation.

BACKGROUND: The prevalence of sleep-disordered breathing (SDB) in patients with prolonged mechanical ventilation (PMV) is unknown. The aim of this study was to assess the frequency of SDB in patients admitted to a long-term acute care (LTAC) hospital who weaned from PMV. METHODS: Retrospective chart review was conducted of all PMV patients who had in-patient polysomnography (PSG) between January 2007 and May 2010. Main outcome measures included the frequency of SDB and tracheostomy decannulation. RESULTS: Nineteen patients were studied, age 53.4 ± 13.4 years, 11 males (57.9%), with mean body mass index of 44.0 ± 12.7 kg/m(2) (range 27.3-75.7). Eighteen patients (94.7%) demonstrated SDB as evidenced by obstructive sleep apnea (OSA), with a median respiratory disturbance index (RDI) of 24.2 events/h (range 5.9-82.0 events/h). Fourteen patients underwent successful positive airway pressure titration, with improvement in the median RDI to 0.9 events/h (range 0.0-9.1 events/h) (P < .001). Seventeen patients (89.5%) were decannulated without adverse event. CONCLUSIONS: There may be a high prevalence of unrecognized SDB in patients who are candidates for decannulation after weaning from PMV.

Images: polysomnographic findings of nystagmus caused by a midbrain hemorrhagic stroke.

Brainstem strokes can present with an array of ophthalmologic findings depending on the location of the lesion. Eye movements are recorded on electrooculogram during polysomnography for sleep staging. We present the case of a patient with a dorsal midbrain hemorrhagic stroke and nystagmus with distinct findings on the electrooculogram during polysomnography. These eye movements from nystagmus differed in many aspects (frequency and amplitude) from the classic findings of other eye movements recorded during different stages of sleep. These polysomnography findings have not been reported in the setting of midbrain stroke. Future studies comparing nystagmus in multiple sleep stages in stroke patients would be of interest. CITATION: Shoukat U, Glick DR, Chaturvedi S, Diaz-Abad M. Images: Polysomnographic findings of nystagmus caused by a midbrain hemorrhagic stroke. J Clin Sleep Med. 2022;18(5):1479-1482.

Average volume-assured pressure support for patients with obstructive sleep apnea with failed CPAP titration.

Objectives: Obstructive sleep apnea (OSA) is a common disease, often treated using continuous positive airway pressure (CPAP) therapy. In many cases, patients fail a CPAP titration study due to inadequate control of the apnea-hypopnea index (AHI, events/hour) or due to treatment-emergent central sleep apnea (TE-CSA). We report our experience using a mode of non-invasive ventilation for alternative treatment of these patients. Material and Methods: We reviewed records of adults who had OSA with AHI≥15 diagnosed on polysomnography (PSG) with failed CPAP titration and in whom titrations with average volume-assured pressure support (AVAPS) with auto-titrating expiratory positive airway pressure were performed. Results: Forty-five patients, age 57.9±13.1 y, 26 males, body mass index (BMI) 40.2±8.7kg/m2. Reasons for CPAP titration failure included: TE-CSA (25, 55.6%) and inadequate control of AHI at maximum CPAP of 20cm H2O (20, 44.4%). Changes noted from baseline PSG to AVAPS titration: AHI: 65.3±29.3 decreased to 22.3±16.1 (p<0.001). Median time SpO2 ≤88%: 63.7 to 6.9min (p<0.001). In 16 patients the AHI was reduced to <15 and in 16 additional patients the AHI was reduced to <30. Improvement in AHI was not related to gender, age, or opioid use, but was correlated with BMI: ∆AHI=12.2 - (1.4 * BMI); p=0.05. AVAPS resulted in improved sleep architecture: median N3 sleep increased: 1.4% to 19.6% total sleep time (TST) (p<0.001), and median R sleep increased: 6.4% to 13.6% TST (p<0.01). Discussion: For patients with OSA for whom CPAP titration failed, titration with AVAPS may be an effective treatment.

Spirometry testing for extracorporeal membrane oxygenation (ECMO) bridge to transplant patients.

PURPOSE: ECMO can provide a bridge to transplantation and improve survival for patients with advanced lung disease. Although pulmonary function testing (PFT) is an important component of the lung allocation score (LAS), it is not always feasible on patients requiring ECMO. While generally safe, PFT testing has contraindications and is not recommended in unstable patients. Currently there are no recommendations regarding the performance of spirometry in ECMO patients. STUDY DESIGN: and Methods: We reviewed data on five patients with advanced lung disease requiring ECMO-bridge to transplant. After careful consideration of the theoretical physiologic risks associated with forced expiratory maneuvers, bedside spirometry was performed in order to update the patients' LAS. RESULTS: All patients successfully completed three forced expiratory maneuvers in the seated position with a bedside spirometer. Vital signs and ECMO flow were stable during testing and without complication. In 2 patients who had both a LAS pre and post spirometry, the LAS increased by 3-5 points. CONCLUSION: Spirometry results are pivotal to organ allocation under current organ sharing protocols. This case series demonstrates that bedside spirometry testing may be performed safely in patients on ECMO awaiting lung transplantation without appreciable side effects, leading to a more accurate LAS score.

Poor Sleep Quality and Other Risk Factors for Unemployment Among Patients on Opioid Agonist Treatment.

Purpose: Patients with opioid use disorder (OUD) face high rates of unemployment, putting them at higher risk of treatment nonadherence and poor outcomes, including overdose death. The objective of this study was to investigate sleep quality and its association with other biopsychosocial risk factors for unemployment in patients receiving opioid agonist treatment (OAT) for OUD. Methods: Using a cross-sectional survey design, participants from 3 OAT programs for OUD completed questionnaires to measure sleep quality (Pittsburgh Sleep Quality Index [PSQI]); pain disability; catastrophic thinking; injustice experience; quality of life; and self-assessed disability. Spearman's rank correlation was used to test for associations between sleep quality and other study variables. Results: Thirty-eight participants completed the study, with mean age 45.6 ± 10.9 years, 27 (71.1%) males, and 16 (42.1%) reporting a high school diploma/equivalent certification as the highest level of academic attainment. Poor sleep quality (defined as PSQI > 5) was identified in 29 participants (76.3%) and was positively correlated with pain disability (r = 0.657, P < .01), self-assessed disability (r = 0.640, P < .001), symptom catastrophizing (r = 0.499, P < .001), and injustice experience (r = 0.642, P < .001), and negatively correlated with quality of life (r = -0.623, P < .001). Conclusions: There was a high prevalence of poor sleep quality in patients with OUD on OAT and this was associated with multiple known risk factors for unemployment. These findings warrant the consideration of regular screening for sleep problems and the inclusion of sleep-related interventions to improve sleep quality, decrease the unemployment rate, and enhance the recovery process for individuals with OUD undergoing OAT.

Granulomatous Pneumocystis jiroveci Pneumonia in an HIV-Positive Patient on Antiretroviral Therapy: A Diagnostic Challenge.

Human Immunodeficiency Virus (HIV)-related Opportunistic Infections (OI), including Pneumocystis jiroveci pneumonia (PCP), have become much less commonplace with anti-retroviral therapy (ART). Despite this, OIs are still common and it is important to remain vigilant for their presence and be aware of how ART and OI chemoprophylaxis may lead to atypical disease presentations. We present the case of a 51-year-old woman with HIV and CD4+ T helper lymphocytes cell count > 200 cells/ul on both ART and trimethoprim/sulfamethoxazole prophylaxis who presented with cavitating lung masses, mediastinal lymphadenopathy and pleural effusions. Negative bronchoalveolar lavage (BAL) and transbronchial biopsy (TBBx) prompted a second diagnostic procedure with a transthoracic core needle biopsy; the final diagnosis was granulomatous PCP. This case showcases a very rare presentation of PCP, with both large cavitating lung masses on imaging and granulomatous reaction on pathology, as well as the challenge of a potentially missed diagnosis with negative BAL and TBBx requiring transthoracic core needle biopsy for a final diagnosis.

Atraumatic Splenic Rupture Associated with Influenza A (H1N1) Pneumonia: Case Report and Review of the Literature.

Influenza virus infection may present with fever, chills, headache, myalgia, malaise, and respiratory symptoms, with a few cases developing into pneumonia, respiratory failure, and other organ damage. Very few cases of atraumatic splenic rupture associated with influenza infection have been reported. Atraumatic splenic rupture, while rare, is associated with high mortality. Here, we report the first case of atraumatic splenic rupture associated with influenza infection in the English literature and review the prior reported literature. The patient was diagnosed with influenza A (H1N1) pneumonia and subsequently developed hemorrhagic shock requiring emergency laparotomy and removal of the ruptured spleen.

Improving sleep medicine education among health professions trainees.

STUDY OBJECTIVES: Despite increasing recognition of its importance, sleep medicine education remains limited during medical training. We sought to assess the baseline knowledge of a group of health professions trainees and to determine whether an educational sleep medicine "boot camp" led to improvement in sleep medicine knowledge. METHODS: Participants attended a 2-day introduction to sleep medicine course designed for new sleep medicine fellows in July 2017 and 2018. Participants completed 2 validated sleep knowledge questionnaires (The Assessment of Sleep Knowledge in Medical Education and The Dartmouth Sleep Knowledge and Attitude Survey) prior to and at the conclusion of the course. RESULTS: A total of 21 health professions trainees including 14 sleep medicine fellows completed both presurveys and postsurveys. Baseline Assessment of Sleep Knowledge in Medical Education Survey score was 21.4 ± 3.4 out of 30 (71.4% ± 11.4%) and baseline Dartmouth Sleep Knowledge and Attitude Survey score was 16.1 ± 2.4 out of 24 (67.3% ± 9.9%). There was no difference in baseline scores between sleep medicine fellows and other health professions trainees. There was a statistically significant improvement in the Assessment of Sleep Knowledge in Medical Education Survey (2.9 ± 2.1 points, P = .004) and Dartmouth Sleep Knowledge and Attitude Survey (2.5 ± 3.0 points, P = .001) scores among all participants after the course, without a difference in degree of improvement among sleep medicine fellows compared to other health professions trainees. CONCLUSIONS: Our findings suggest that baseline sleep medicine knowledge is higher than previously reported among health professions trainees. An educational sleep medicine boot camp improved knowledge even in a group of learners with high baseline knowledge and interest in sleep medicine, including new sleep medicine fellows. CITATION: Wappel SR, Scharf SM, Cohen L, et al. Improving sleep medicine education among health profession trainees. J Clin Sleep Med. 2021;17(12):2461-2466.

Assessing calorie and protein recommendations for survivors of critical illness weaning from prolonged mechanical ventilation - can we find a proper balance?

BACKGROUND & AIMS: Survivors of critical illness requiring prolonged mechanical ventilation (PMV) are predisposed to malnutrition, muscle wasting, and weakness. There is a lack of data regarding nutrition adequacy among these patients, and although nitrogen balance has been studied as a marker of adequate protein intake in healthy individuals and acutely critically ill patients, it has not been well studied in critically ill patients with PMV. The purpose of this study was to determine if patients requiring PMV admitted to a long-term acute care hospital (LTACH) achieved registered dietitian (RD) recommended goals for energy and protein intake and if the recommendations were adequate to avoid negative nitrogen balance. METHODS: Using a retrospective, cohort study design, patients requiring PMV who had orders for 24-h urine collections for urea nitrogen (24hrUUN) were included. Energy and protein intake was calculated from chart documentation of dietary intake for the 24-h period during which patients underwent a 24hrUUN. Nitrogen intake was estimated from protein intake. Dietary intake was compared to RD-recommendations to determine the percentage of RD-recommendations achieved. Nitrogen balance was calculated as nitrogen intake minus nitrogen loss, with negative balance categorized as less than -1. RESULTS: Subjects (n = 16) were 38% male and 75% African American (mean age 61.5 ± 3.2 years; mean BMI 27.5 ± 2.5 kg/m2). Duration of LTACH hospitalization was 26.5 (6-221) days. Mean energy and protein intake was 21.7 ± 2.9 kcal/kg/d and 1.1 ± 0.1 g/kg/d, respectively, which corresponded to 86% of both RD energy and protein recommendations. Ten patients achieved a positive nitrogen balance (mean 0.9 ± 1.1 g). In addition, there was a positive linear relationship between protein intake and nitrogen balance (r = 0.59, p = 0.016). CONCLUSION: Survivors of critical illness requiring PMV achieved a high percentage of RD-recommended protein and calories, and prevented a negative nitrogen balance in a majority of patients. Increasing protein intake can prevent a negative nitrogen balance. Future studies should evaluate whether these patients are able to maintain a steady state of nitrogen intake and excretion over time and how this affects time to and/or success of weaning.

A successful case of extracorporeal membrane oxygenation for COVID-19: walking home without oxygen supplementation.

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged from Wuhan, China in December 2019 and is the strain of coronavirus that causes coronavirus disease 2019 (COVID-19). Approximately one-third of the patients with COVID-19 require intensive care unit (ICU) admission, and almost 30% of the patients develop acute respiratory distress syndrome (ARDS). Extracorporeal membrane oxygenation (ECMO) is used as salvage therapy for severe ARDS. The role of ECMO in the treatment of COVID-19 remains unclear, although there is emerging evidence that this approach may be an effective salvage therapy for severe ARDS. Case Presentation: We present a case of a previously healthy 39-year-old Hispanic male who presented to the hospital with flu-like symptoms, including headache, fatigue, and myalgia for 8 days in late April 2020. He denied dyspnea on exertion. The patient's symptoms progressed, resulting in pneumonia and acute respiratory distress syndrome (ARDS). The patient was managed with prone positioning, convalescent plasma and veno-venous extracorporeal membrane oxygenation (VV-ECMO) for 35 days. The patient successfully recovered and was able to ambulate independently and was discharged home from an acute care hospital without oxygen supplementation on hospital day 63. Conclusion: We present one of the first few documented cases of ECMO for severe ARDS due to COVID-19. After a prolonged hospital course requiring VV-ECMO, the patient was discharged home from an acute care hospital without oxygen requirement and ambulated independently, likely as a result of daily aggressive mobility-focused rehabilitation.

The role of non-invasive ventilation in weaning and decannulating critically ill patients with tracheostomy: A narrative review of the literature.

INTRODUCTION: Invasive mechanical ventilation (IMV) is associated with several complications. Placement of a long-term airway (tracheostomy) is also associated with short and long-term risks for patients. Nevertheless, tracheostomies are placed to help reduce the duration of IMV, facilitate weaning and eventually undergo successful decannulation. METHODS: We performed a narrative review by searching PubMed, Embase and Medline databases to identify relevant citations using the search terms (with synonyms and closely related words) "non-invasive ventilation", "tracheostomy" and "weaning". We identified 13 publications comprising retrospective or prospective studies in which non-invasive ventilation (NIV) was one of the strategies used during weaning from IMV and/or tracheostomy decannulation. RESULTS: In some studies, patients with tracheostomies represented a subgroup of patients on IMV. Most of the studies involved patients with underlying cardiopulmonary comorbidities and conditions, and primarily involved specialized weaning centres. Not all studies provided data on decannulation, although those which did, report high success rates for weaning and decannulation when using NIV as an adjunct to weaning patient off ventilatory support. However, a significant percentage of patients still needed home NIV after discharge. CONCLUSIONS: The review supports a potential role for NIV in weaning patients with a tracheostomy either off the ventilator and/or with its decannulation. Additional research is needed to develop weaning protocols and better characterize the role of NIV during weaning.