Respiratory Failure In Patients Research Articles

Leukocyte-platelet aggregates in the pathogenesis of respiratory failure in patients with COVID-19 with varying degrees of oxygen support

Leukocyte-platelet aggregates in the pathogenesis of respiratory failure in patients with COVID-19 with varying degrees of oxygen support

Nonlinear relationship between platelet count and 30-day in-hospital mortality in ICU acute respiratory failure patients: a multicenter retrospective cohort study

BackgroundLimited evidence exists regarding the link between platelet count and 30-day in-hospital mortality in acute respiratory failure (ARF) patients. Thus, this study aims to investigate this association among ICU patients experiencing acute respiratory failure.MethodsWe conducted a retrospective cohort study across multiple centers, utilizing data from the US eICU-CRD v2.0 database covering 22,262 patients with ARF in the ICU from 2014 to 2015. Our aim was to investigate the correlation between platelet count and 30-day in-hospital mortality using binary logistic regression, subgroup analyses, and smooth curve fitting.ResultsThe 30-day in-hospital mortality rate was 19.73% (4393 out of 22,262), with a median platelet count of 213 × 109/L. After adjusting for covariates, our analysis revealed an inverse association between platelet count and 30-day in-hospital mortality (OR = 0.99, 95% CI 0.99, 0.99). Subgroup analyses supported the robustness of these findings. Furthermore, a nonlinear relationship was identified between platelet count and 30-day in-hospital mortality, with the inflection point at 120 × 109/L. Below the inflection point, the effect size (OR) was 0.89 (0.87, 0.91), indicating a significant association. However, beyond this point, the relationship was not statistically significant.ConclusionThis study establishes a clear negative association between platelet count and 30-day in-hospital mortality among ICU patients with ARF. Furthermore, we have identified a nonlinear relationship with saturation effects, indicating that among ICU patients with acute respiratory failure, the lowest 30-day in-hospital mortality rate occurs when the baseline platelet count is approximately 120 × 109/L.

Exploring variable observational time windows for patient–ventilator asynchrony during mechanical ventilation treatment

Background and Objective:Patient–ventilator asynchrony (PVA) is prevalent in mechanical ventilation (MV) for critically ill patients and has been associated with adverse patient outcomes. However, studies investigating the associations between PVA and patient outcomes employ differing time windows for PVA evaluation. In this study, machine learning methods are used to quantify the prevalence and magnitude of asynchrony at different time windows, as well as its temporal trends. The study aims to identify the optimal time window for assessing the temporal changes in the asynchrony index (AI) and magnitude of asynchrony (Masyn,avg). Methods:This study uses Convolutional Neural Networks (CNN) and Convolutional Autoencoders (CAE) to detect incidences of PVA and quantify its severity in 30 MV respiratory failure patients with 2722 h of respiratory data. The frequency of PVA and the breath-average magnitude were determined over different time periods, t, where t=0.5, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 45, 60 min and throughout MV. The AI for the patients was determined using the CNN model. Given an asynchronous breath, the CAEs were used to reconstruct asynchrony-free waveforms. The Masyn,avg was quantified as the difference between the two waveforms. The change in AI (ΔAI) and the change in Masyn,avg (ΔMasyn,avg) for all time windows, t were also calculated for each patient. Results:The median [interquartile range] overall AI and Masyn,avg for the patient cohort are 24.8 [12.9–46.1]% and 37.2 [33.4–45.3]% respectively. Analysis of the patient cohort also shows significant intra-patient variability in AI and Masyn,avg, while the inter-patient variation in AI is greater as compared to Masyn,avg. The cohort mean ΔAI and ΔMasyn,avg exhibit a converging trend with a minima at t=5 min and with values of 5.32 ± 2.37% and 2.80 ± 1.03%, respectively. A time window of t=5 min was preferred for AI and Masyn,avg evaluation as it can capture the granular changes in asynchrony while also being representative of longer temporal trends, thus preventing excessive variations in patient AI and Masyn,avg. Conclusion:Overall, this study provides new insight into both the short- and long-term trends of PVA in MV patients. By understanding these patterns, healthcare providers can enhance the monitoring of MV, leading to more informed and timely intervention. Ultimately, this could lead to improved patient care and outcomes.

The ventilatory effect of High Velocity Nasal Insufflation versus Non-invasive Positive Pressure Ventilation in the treatment of acute hypercapnic respiratory failure in patients with AECOPD.

The ventilatory effect of High Velocity Nasal Insufflation versus Non-invasive Positive Pressure Ventilation in the treatment of acute hypercapnic respiratory failure in patients with AECOPD.

Digital Twins of Acute Hypoxemic Respiratory Failure Patients Suggest a Mechanistic Basis for Success and Failure of Noninvasive Ventilation.

To clarify the mechanistic basis for the success or failure of noninvasive ventilation (NIV) in acute hypoxemic respiratory failure (AHRF). We created digital twins based on mechanistic computational models of individual patients with AHRF. Interdisciplinary Collaboration in Systems Medicine Research Network. We used individual patient data from 30 moderate-to-severe AHRF patients who had failed high-flow nasal cannula (HFNC) therapy and subsequently underwent a trial of NIV. Using the digital twins, we evaluated lung mechanics, quantified the separate contributions of external support and patient respiratory effort to lung injury indices, and investigated their relative impact on NIV success or failure. In digital twins of patients who successfully completed/failed NIV, after 2 hours of the trial the mean (sd) of the change in total lung stress was -10.9 (6.2)/-0.35 (3.38) cm H2O, mechanical power -13.4 (12.2)/-1.0 (5.4) J/min, and total lung strain 0.02 (0.24)/0.16 (0.30). In the digital twins, positive end-expiratory pressure (PEEP) produced by HFNC was similar to that set during NIV. In digital twins of patients who failed NIV vs. those who succeeded, intrinsic PEEP was 3.5 (0.6) vs. 2.3 (0.8) cm H2O, inspiratory pressure support was 8.3 (5.9) vs. 22.3 (7.2) cm H2O, and tidal volume was 10.9 (1.2) vs. 9.4 (1.8) mL/kg. In digital twins, successful NIV increased respiratory system compliance +25.0 (16.4) mL/cm H2O, lowered inspiratory muscle pressure -9.7 (9.6) cm H2O, and reduced the contribution of patient spontaneous breathing to total driving pressure by 57.0%. In digital twins of AHRF patients, successful NIV improved lung mechanics, lowering respiratory effort and indices associated with lung injury. NIV failed in patients for whom only low levels of positive inspiratory pressure support could be applied without risking patient self-inflicted lung injury due to excessive tidal volumes.

An evaluation of noninvasive mechanical ventilation application in intensive care

Aims: Noninvasive mechanical ventilation (NIMV) is a positive pressure treatment applied with a mask without the need for endotracheal intubation in patients with acute and chronic respiratory failure. C-reactive protein (CRP), procalcitonin (PCT), albumin, red blood cell distribution width (RDW), and mean platelet volume (MPV) are frequently used markers in clinical practice. Arterial blood gas (ABG) analysis is a standard method in clinical practice in intensive care, which is known to have a higher risk of complications than venous blood gas (VBG) analysis. Studies have shown a strong correlation between ABG and VBG with regard to pH, partial arterial carbon dioxide pressure (PCO2), and serum bicarbonate (HCO3). In this study, we aimed to evaluate the relationship between CRP, PCT, albumin, MPV, and RDW and in-hospital mortality and acute respiratory failure in patients undergoing NIMV. Our secondary aim was to evaluate the relationship between these parameters and VBG values. Methods: Patients with acute hypoxemic and hypercapnic respiratory failure that underwent NIMV in intensive care unit (ICU) were evaluated retrospectively. Results: The study included 99 patients with a mean age of 69.39±9.79 years. In-hospital mortality occurred in 5 (5.1%) patients. Hypercapnic respiratory failure was detected in 66 (66.7%), hypoxemic respiratory failure in 19 (19.2%), and hypoxemic + hypercapnic respiratory failure in 14 (14.1%) patients. PCT was significantly higher in patients with acute hypoxemic respiratory failure and MPV was significantly higher in patients with acute hypercapnic respiratory failure compared to other patients (p<0.05 for both). Both MPV and RDW were significantly higher in patients with in-hospital mortality (p<0.05). The baseline and 24-h PO2/FiO2 ratios were significantly lower in patients with acute hypoxemic + hypercapnic respiratory failure (p<0.05). The 24-h PO2/FiO2 ratio was significantly lower in patients with in-hospital mortality compared to patients without mortality (p<0.05). Conclusion: Both RDW and MPV should be employed in predicting mortality in patients undergoing NIMV due to acute respiratory failure. Further multicenter, prospective studies are needed to evaluate the PaO2/FiO2 ratio particularly in VBG in patients receiving NIMV due to acute respiratory failure.

ROX Index Variation as a Predictor of Outcomes in COVID-19 Patients.

Background: During the COVID-19 pandemic, emergency departments were overcrowded with critically ill patients, and many providers were confronted with ethical dilemmas in assigning respiratory support to them due to scarce resources. Quick tools for evaluating patients upon admission were necessary, as many existing scores proved inaccurate in predicting outcomes. The ROX Index (RI), a rapid and straightforward scoring system reflecting respiratory status in acute respiratory failure patients, has shown promise in predicting outcomes for COVID-19 patients. The 24 h difference in the RI accurately gauges mortality and the need for invasive mechanical ventilation (IMV) among patients with COVID-19. Methods: Study design: Prospective cohort study. A total of 204 patients were admitted to the emergency department from May to August 2020. Data were collected from the clinical records. The RI was calculated at admission and 24 h later, and the difference was used to predict the association with mortality and the need for IMV, a logistic regression model was used to adjust for age, sex, presence of comorbidities, and disease severity. Finally, the data were analyzed using ROC. Results: The difference in respiratory RI between admission and 24 h is a good predictor for death (AUC 0.92) and for mechanic ventilation (AUC: 0.75). Each one-unit decrease in the RI difference at 24 h was associated with an odds ratio of 1.48 for the risk of death (95%CI: 1.31-1.67) and an odds ratio of 1.16 for IMV (95% IC: 1.1-1.23). Conclusions: The 24 h variation of RI is a good prediction tool to allow healthcare professionals to identify the patients who will benefit from invasive treatment, especially in low-resource settings.

Severe respiratory failure secondary to unilateral phrenic nerve injury: A case report

AbstractPatients with unilateral phrenic nerve paralysis are usually asymptomatic at rest. We present a 77‐year‐old woman with a chest wall osteoarthropathy associated with synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome that developed severe hypercapnic respiratory failure following cryoballoon ablation for the management of atrial fibrillation. Her right phrenic nerve injury (PNI) was confirmed by chest radiography, phrenic nerve conduction studies, and diaphragmatic ultrasonography. We conclude that unilateral PNI during ablation invalidated the diaphragmatic compensation for pre‐existing reduced thoracic expansion, resulted in severe hypoventilation. Clinicians should be careful of the fact even unilateral PNI could cause catastrophic respiratory failure in patients with restricted thoracic expansion.

A Diagnostic Nomogram for Predicting Hypercapnic Respiratory Failure in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

To develop and validate a nomogram for assessing the risk of developing hypercapnic respiratory failure (HRF) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). From January 2019 to August 2023, a total of 334 AECOPD patients were enrolled in this research. We employed the Least Absolute Shrinkage and Selection Operator (LASSO) regression and multivariate logistic regression to determine independent predictors and develop a nomogram. This nomogram was appraised by the area under the receiver operating characteristic curve (AUC), calibration curve, Hosmer-Lemeshow goodness-of-fit test (HL test), decision curve analysis (DCA), and clinical impact curve (CIC). The enhanced bootstrap method was used for internal validation. Sex, prognostic nutritional index (PNI), hematocrit (HCT), and activities of daily living (ADL) were independent predictors of HRF in AECOPD patients. The developed nomogram based on the above predictors showed good performance. The AUCs for the training, internal, and external validation cohorts were 0.841, 0.884, and 0.852, respectively. The calibration curves and HL test showed excellent concordance. The DCA and CIC showed excellent clinical usefulness. Finally, a dynamic nomogram was developed (https://a18895635453.shinyapps.io/dynnomapp/). This nomogram based on sex, PNI, HCT, and ADL demonstrated high accuracy and clinical value in predicting HRF. It is a less expensive and more accessible approach to assess the risk of developing HRF in AECOPD patients, which is more suitable for primary hospitals, especially in developing countries with high COPD-related morbidity and mortality.

Implementation and Mixed-Methods Assessment of an Early Mobility Interprofessional Education Simulation.

Extended periods of bed rest and mechanical ventilation (MV) have devastating effects on the body. Early mobility (EM) for patients in respiratory failure is safe and feasible, and an interprofessional team is recommended. Using simulation to train EM skills improves student confidence. The purpose of this study was to enable health care student collaboration as an interprofessional team in providing safe management and monitoring during an EM simulation for a patient requiring MV. Nursing (n = 33), respiratory (n = 7), occupational (n = 24), and physical therapist students (n = 55) participated in an EM interprofessional education (IPE) simulation experience. A mixed-methods analytic approach was used with pre/post quantitative analysis of the Student Perceptions of Interprofessional Clinical Education-Revised, Version 2 instrument and qualitative analysis of students' guided reflection papers. Pre/post surveys completion rate was 39.5% (n = 47). The Student Perceptions of Interprofessional Clinical Education-Revised, Version 2 instrument indicated a significant improvement (P = .037) in students' perceptions of interprofessional collaborative practice. Qualitative data showed a positive response to the EM simulation IPE. Themes reflected all 4 Interprofessional Education Collaborative competencies. This study demonstrated improved perception of interprofessional collaborative practice and better understanding of the Interprofessional Education Collaborative competencies. Students collaborated in the simulation-based IPE to provide EM for a patient requiring MV and reported perceived benefits of the experience.

Autonomic Function and Baroreflex Control in COVID-19 Patients Admitted to the Intensive Care Unit.

Background: Autonomic function and baroreflex control might influence the survival rate of coronavirus disease 2019 (COVID-19) patients admitted to the intensive care unit (ICU) compared to respiratory failure patients without COVID-19 (non-COVID-19). This study describes physiological control mechanisms in critically ill COVID-19 patients admitted to the ICU in comparison to non-COVID-19 individuals with the aim of improving stratification of mortality risk. Methods: We evaluated autonomic and baroreflex control markers extracted from heart period (HP) and systolic arterial pressure (SAP) variability acquired at rest in the supine position (REST) and during a modified head-up tilt (MHUT) in 17 COVID-19 patients (age: 63 ± 10 years, 14 men) and 33 non-COVID-19 patients (age: 60 ± 12 years, 23 men) during their ICU stays. Patients were categorized as survivors (SURVs) or non-survivors (non-SURVs). Results: We found that COVID-19 and non-COVID-19 populations exhibited similar vagal and sympathetic control markers; however, non-COVID-19 individuals featured a smaller baroreflex sensitivity and an unexpected reduction in the HP-SAP association during the MHUT compared to the COVID-19 group. Nevertheless, none of the markers of the autonomic and baroreflex functions could distinguish SURVs from non-SURVs in either population. Conclusions: We concluded that COVID-19 patients exhibited a more preserved baroreflex control compared to non-COVID-19 individuals, even though this information is ineffective in stratifying mortality risk.

Outcomes of bailout use of continuous positive airway pressure in patients with severe COVID-19 respiratory failure

During the first wave of the Coronavirus-19 (COVID-19) pandemic, due to an overflow of patients in the ICU, continuous positive airway pressure (CPAP) was used as a last resort to mechanical ventilation. The purpose of this study is to evaluate prognostic factors in COVID-19 severe respiratory failure patients treated with helmet CPAP. We reviewed the medical records of COVID-19 respiratory failure patients treated with H-CPAP at the Emergency Department from February 23rd to March 14th, 2020. A total of 202 (40%) patients admitted for respiratory failure due to COVID-19 pneumonia were considered. 129 (64%) patients received H-CPAP, while 73 (36%) required endotracheal intubation and invasive mechanical ventilation despite initial H-CPAP. 99 patients (49%) died. The mortality rate in the IMV group was 37%, compared to 56% in the group that received only H-CPAP (p= 0.004). The age and comorbidities of patients in the two groups differed significantly (p < 0.001). Age and PaO2/FiO2 were identified as the only independent risk factors for death. Identifying these independent predictors of mortality in patients with acute respiratory insufficiency may help clinicians optimize treatment escalation.

To NIRS or not: understanding clinical decision-making of respiratory support management related to acute respiratory failure using Critical Decision Method

Clinical decisions related to noninvasive respiratory support (NIRS) for acute respiratory failure patients are complex. NIRS strategies have favorable benefits for patients when successful but NIRS failure comes with longer ICU stays, increased mortality, and more intubation-related and mechanical ventilator-associated complications. Our goal is to understand how physicians make decisions regarding NIRS and explore the differences between emergency physicians and critical care physicians—who commonly make these decisions. We used the critical decision method to conduct ten semi-structured interviews with five emergency physicians and five critical care physicians from ten different healthcare systems across the United States. We found that physicians similarly use objective and subjective clinical cues but differentially use temporal and contextual cues in their decision-making. Several insights identified in our study can be helpful in the design and development of clinical decision support systems for respiratory support decision-making. Specifically, we recommend two customized distinct clinical decision support systems for respiratory support decision-making, one for each designated clinical setting (i.e., ED and ICU) with tailored designs that support the different decision-making processes.

FREQUENCY OF TYPE-II RESPIRATORY FAILURE IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE

Background: In chronic obstructive pulmonary disease (COPD) patients the alveoli do not ventilate fully due to bronchial obstruction. This leads to the incomplete ventilation, incomplete clearance of carbon dioxide causing hypercapnia. There are some muscular abnormalities also in COPD patients. All these pathogeneses lead to type 2 (hypercapnic) respiratory failure. The aim of this study was to determine the frequency of type II respiratory failure in patients with COPD. Methods: This descriptive cross-sectional study was conducted at Department of Medicine, Hayatabad Medical Complex, Peshawar from 21st Aug 2021 to 20th Feb 2022. A total of 129 patients with COPD were enrolled. COPD was diagnosed based on clinical findings and confirmation with spirometry showing FEV1/FVC less than 70% of predicted. Confirmation of type II respiratory failure was done by Arterial-blood gas (ABG) test on heparinized arterial blood sample analysis showing hypercapnia (Paco2 ?45 mmHg). Results: Type II respiratory failure was observed in 31 patients (24%); 19 (22.9%) patients with type respiratory failure had age more than 55 years. Eight (36.4%) patients with type II respiratory failure had GOLD stage 4 COPD. Age of the patients ranged from 40 to 65 years with mean age 53.410±9.362 years. Male to female ratio was 2.4:1. Conclusion: Type 2 respiratory failure is more prevalent in elder patients above 55 years of age, and is more common among males. The severity of COPD does not appear to have a direct relationship with the occurrence of type 2 respiratory failure. Pak J Physiol 2024;20(1):33-6

Venous blood gases in the assessment of respiratory failure in patients undergoing sleep studies: a randomized study.

Venous blood gases (VBGs) are not consistently considered suitable surrogates for arterial blood gases (ABGs) in assessing acute respiratory failure due to variable measurement error. The physiological stability of patients with chronic ventilatory failure may lead to improved agreement in this setting. Adults requiring ABGs for sleep or ventilation titration studies had VBGs drawn before or after each ABG, in a randomized order. Veno-arterial correlation and agreement were examined for carbon dioxide tension (PCO2), pH, oxygen tension (PO2), and oxygen saturation (SO2). We analyzed 115 VBG-ABG pairs from 61 patients. Arterial and venous measures were correlated (P < .05) for PCO2 (r = .84) and pH (r = .72), but not for PO2 or SO2. Adjusted mean veno-arterial differences (95% limits of agreement) were +5.0 mmHg (-4.4 to +14.4) for PCO2; -0.02 (-0.09 to +0.04) for pH; -34.3 mmHg (-78.5 to +10.0) for PO2; and -23.9% (-61.3 to +13.5) for SO2. VBGs obtained from the dorsal hand demonstrated a lower mean PCO2 veno-arterial difference (P < .01). A venous PCO2 threshold of ≥ 45.8 mmHg was > 95% sensitive for arterial hypercapnia, so measurements below this can exclude the diagnosis without an ABG. A venous PCO2 threshold of ≥ 53.7 mmHg was > 95% specific for arterial hypercapnia, so such readings can be assumed diagnostic. The area under the receiver operating characteristic curve of 0.91 indicated high discriminatory capacity. A venous PCO2 < 45.8 mmHg or ≥ 53.7 mmHg would exclude or diagnose hypercapnia, respectively, in patients referred for sleep studies, but VBGs are poor surrogates for ABGs where precision is important. Registry: Australian New Zealand Clinical Trials Register; Name: A comparison of arterial and blood gas analyses in sleep studies; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=372717; Identifier: ACTRN12617000562370. Lindstrom SJ, McDonald CF, Howard ME, etal. Venous blood gases in the assessment of respiratory failure in patients undergoing sleep studies: a randomized study. J Clin Sleep Med. 2024;20(8):1259-1266.

Factors Associated With Respiratory Failure After Open Ventral Hernia Repair: An Evaluation of the NSQIP Database.

An analysis of ACS-NSQIP open ventral hernia repair (OVHR) data (2017-2019) was performed. Respiratory failure (RF) occurred in 643 patients (1%) and not in 63,213 (99%) (nRF). Respiratory failure patients were older (63.7 vs 57years, P < .001) and more comorbid: insulin-dependent diabetes (14.7% vs 5.8%, P < .001), COPD (19.4% vs 5.2%, P < .001), BMI (36.0 vs 32.8, P < .001), and current tobacco use (24.9% vs 17.6%, P < .001). Respiratory failure patients had greater ASA scores (ASA 3: 63.3% vs 47.8%, P < .001), bowel resection (8.2% vs 1.3%, P < .001), component separation (20.1% vs 9.0%, P < .001), operative times (178.4 vs 98.8minutes, P < .001), complications (deep wound infections 3.6% vs 1.0%, organ space infections 13.2% vs 1.0%, wound dehiscence 3.1% vs 0.6%, acute renal failure 11.7% vs 0.1%), and hospital stay (13.7 vs 2.3 days), with fewer home discharges (44.3% vs 96.4%) (all P < .001). Respiratory failure patients had higher mortality compared to nRF (20.2% vs 0.1%, P < .001). Respiratory failure after OVHR is rare but correlates closely with significant wound, systemic, and social complications. Preoperative management of risk factors would be appropriate in high-risk patients.

Risk factors for intubation and mortality in patients treated with high flow nasal cannula due to COVID-19 infection. Survival Analysis Study in a Northern Mexican Population.

COVID-19-related acute hypoxic respiratory failure patients often use high-flow nasal cannula (HFNO) oxygen therapy. COVID-19 HFNO intubation and mortality risk factors are understudied in the Mexican population, so the aim was to study them. This retrospective study searched electronic medical records from March 2020 to June 2022 for patients with COVID-19 who required hospitalization and HFNO. Descriptive statistics, a survival curve analysis, and Cox proportional hazard models were used to determine predictor factors for intubation and mortality in patients with HFNO and COVID-19, respectively. A total of 134 patients received HFNO treatment. Ninety-one (67.9%) were men with a mean (SD) age of 54.5 (17.9) years. Common medical history included obesity (n = 89, 66.4%) with a Body Mass Index (BMI) mean (SD) of 31.8 (5.9), hypertension (n = 67, 50.0%), type 2 diabetes (n = 55, 41.0%), and dyslipidemias (n = 43, 32.1%). The variables associated with a greater risk of requiring intubation after high-flow therapy were age (HR = 1.018, 95% CI 1.003-1.034, p = 0.022) and BMI (HR = 1.071, 95% CI 1.024-1.120, p = 0.003). No variables were associated with lower risk. Increased mortality was associated with increasing age (HR = 1.151, 95% CI 1.102-1.201, p = <0.001), hypertension (HR = 4.092, 95% CI 1.369-12.236, p = 0.012), and dyslipidemia (HR = 3.954, 95% CI 1.395-11.209, p = 0.010). Patients with type 2 diabetes had a lower risk of mortality (HR = 0.235, 95% CI 0.080-0.688, p = 0.008). A higher age and BMI were associated with an increased risk of intubation in patients with HFNO and COVID-19. Hypertension and dyslipidemias were associated with a higher risk of mortality.

Outcomes of Acute Respiratory Failure in Patients With Cancer in the United States

ObjectiveTo determine the epidemiological effect-magnitude and outcomes of patients with cancer vs those without cancer who are hospitalized with acute respiratory failure (ARF). Patients and MethodsWe reviewed hospitalizations within the National Inpatient Sample (NIS) database between January 1, 2016, and December 31, 2018. Patients were classified based on a diagnosis of solid-organ cancer, hematologic cancer, or no cancer. Noninvasive positive pressure ventilation (NIPPV) failure was defined as patients who initially received NIPPV and had progression to invasive mechanical ventilation. Weighted samples were used to derive population estimates. ResultsDuring the study period, there were an estimated 8,837,209 admissions with ARF in the United States, 8.9% (783,625) of which had solid-organ cancer and 2.0% (176,095) had hematologic cancers. Annually, 319,907 patients with cancer are admitted with ARF, with 27.3% (87,302) requiring invasive mechanical ventilation and 10.0% (31,998) requiring NIPPV. In-hospital mortality was higher in patients with cancer vs those without cancer (24.0% [76,813] vs 12.3% [322,465]; P<.001), and this proprotion persisted when stratified by the highest method of oxygen delivery. Patients with cancer had longer hospital length of stay (7.0 days [3.0 to 12.0 days] vs 5.0 days [3.0 to 10.0 days]; P<.001) and were more likely to have NIPPV failure (14.9% [3,992] vs 12.8% [41,875]). Compared with those with solid-organ cancer, patients with hematologic cancers experienced worse outcomes. The association between underlying cancer diagnosis and outcomes remained consistent when adjusted for age, sex, and comorbidities. ConclusionIn the United States, patients with cancer account for over 10% of ARF hospital admissions (959,720 of 8,837,209). They experience an approximately 2-fold higher mortality versus those without cancer. Those with hematologic cancers appear to experience worse outcomes than patients with solid-organ cancers.

Hypercapnia is not excluded by normoxia in neuromuscular disease patients: implications for oximetry.

Pulse oximetry is widely used in the assessment of chronic respiratory failure in neuromuscular disease (NMD) patients. Chronic respiratory failure is the major cause of morbidity and mortality, necessitating early diagnosis and intervention. Guidelines suggest that an arterial blood gas (ABG) measurement is indicated if oxygen saturation (S pO2 ) is ≤94% in the absence of lung disease. However, hypercapnia with normoxia (S pO2 ≥95%) has been observed on ABGs of patients with NMD, in particular those with motor neurone disease. A single-centre retrospective audit of room-air ABGs in stable hypercapnic chronic respiratory failure patients from 1990 to 2020 was performed. Patients with parenchymal lung disease were excluded. Patients were grouped into three main categories: non-NMD, other NMD and motor neurone disease. 297 ABGs with hypercapnia from 180 patients with extrinsic restrictive lung disease were analysed. No patients with non-NMD, 54% of patients with other NMD and 36% of motor neurone disease patients demonstrated hypercapnia with normoxia (Chi-squared 61.33; p<0.001). The potential mechanism is proposed to be a difference in calculated respiratory quotient. If the alveolar-arterial gradient is assumed to be normal, the calculated respiratory quotient was significantly higher in motor neurone disease patients and other NMD patients compared with non-NMD patients (estimated marginal mean 0.99, 95% CI 0.94-1.03; 0.86 0.76-0.96; 0.73, 0.63-0.83, respectively; p<0.001) by mixed-model analysis. Hypercapnia is not excluded with normal oximetry in NMD patients and may be due to an elevated respiratory quotient. This has implications in the diagnosis and monitoring of respiratory insufficiency in NMD patients with oximetry alone.

Tenecteplase With Concomitant Anticoagulation for Acute Respiratory Failure in Patients With COVID-19: A Randomized Controlled Trial.

Background Pulmonary thrombosis and thromboembolism play a significant role in the physiologic derangements seen in COVID-19 acute respiratory failure. The effect of thrombolysis with tenecteplase on patient outcomes is unknown. Methods We conducted a randomized, controlled, double-blind, phase II trial comparing tenecteplase versus placebo in patients with COVID-19 acute respiratory failure (NCT04505592). Patients with COVID-19 acute respiratory failure were randomized to tenecteplase 0.25 mg/kg or placebo in a 2:1 proportion. Both groups received therapeutic heparin for at least 72 hours. Results Thirteen patients were included in the trial. Eight patients were randomized to tenecteplase and five were randomized to placebo. At 28 days, 63% (n = 5) of patients assigned to the treatment group were alive and free from respiratory failure compared to 40% (n = 2) in the placebo arm (p = 0.43). Mortality at 28 days was 25% (n = 2) in the treatment arm and 20% (n = 1) in the control arm (p = 1.0). No patients in the treatment arm developed renal failure by 28 days compared to 60% (n = 3) in the placebo arm (p = 0.07). Major bleeding occurred in 25% (n = 2) of the treatment arm and 20% (n = 1) in the placebo arm; however, no patients in either arm experienced intracranial hemorrhage. Conclusions Tenecteplase with concomitant heparin may improve patient outcomes in patients with COVID-19 respiratory failure. As this study was limited by a small sample size, larger confirmatory studies are needed.