Pulmonary benign metastasizing leiomyoma presenting as acute hypoxemic respiratory failure: a case report.

Pulmonary benign metastasizing leiomyoma is an uncommon condition, predominantly affecting women of childbearing age with a history of uterine smooth muscle tumors and uterine leiomyoma surgery for uterine leiomyoma. The progression of PBML is often unpredictable and depends on the extent of lung involvement. Generally, most patients remain asymptomatic, but a minority may experience coughing, wheezing, or shortness of breath, which are frequently misdiagnosed as pneumonia. consequently, this presents significant challenges in both treatment and nursing care before diagnosis. This paper reports the case of a 35-year-old woman primarily diagnosed with acute hypoxic respiratory failure who was transferred from the emergency room to the intensive care unit. The initial computed tomography scan of the patient's lungs indicated diffuse interstitial pneumonia, but the sequencing of the alveolar lavage fluid pathogen macro did not detect any bacteria, fungi, or viruses. Moreover, the patient remained in a persistent hypoxic state before the definitive diagnosis. Therefore, our focus was on maintaining the airway patency of the patient, using prone ventilation, inhaling nitric oxide, monitoring electrical impedance tomography, and preventing ventilator-associated pneumonia to improve oxygenation, while awaiting immunohistochemical staining of the patient's biopsied lung tissue. This would help us clarify the diagnosis and treat it based on etiology. After meticulous treatment and nursing care, the patient was weaned off the ventilator after 26 days and transferred to the respiratory ward after 40 days. This case study may serve as a reference for clinical practice and assist patients suffering from PBML.

From Cosmetic Surgery to Critical Care: Clinical Mimicry of Acute Respiratory Distress Syndrome Following Gluteal Augmentation Surgery.

Gluteal augmentation surgery, commonly known as the Brazilian Butt Lift (BBL), has become increasingly popular and is offered at numerous surgical centers. Typically performed on an outpatient basis, the procedure takes less than four hours, making it an appealing option for many patients. However, BBL is associated with multiple complications, some of which can be severe, resulting in high mortality rates. Most such post-operative adverse events necessitate urgent transfer to hospitals for optimal care, with post-operative respiratory distress being one such critical sign. Fat embolism syndrome (FES) is a notable complication of BBL. The diagnosis of FES is primarily clinical, supported by imaging studies such as chest X-rays and CT scans. FES often goes underdiagnosed due to the lack of definitive diagnostic criteria and its clinical and radiological similarities to other conditions. Despite its underdiagnosis, FES is reported in approximately 0.06% of patients undergoing BBL. Failure to diagnose it early can lead to complications from empiric treatment of other suspected conditions, potentially worsening the prognosis. Our patient developed respiratory failure within an hour after undergoing BBL. The time to symptom onset and the patient's agitation before the respiratory episode broadened the differential for her condition. This case report highlights the importance of recognizing FES and exploring potential preventive measures, including advancements in surgical techniques and prophylactic strategies.

Clinical Characteristics and Risk Factors of Mechanical Ventilation Among COVID-19 Patients on High-Flow Nasal Oxygen (HFNO).

INTRODUCTION: COVID-19 is a viral infection affecting the respiratory system, primarily. It has spread globally ever since it first appeared in China in 2019. The use of high-flow nasal oxygen (HFNO) for the treatment of COVID-19 has not been well established. OBJECTIVES: The primary objectives of this study are to observe the success of HFNO in preventing escalation to mechanical ventilation (MV) and to measure the prevalence of HFNO in King Abdulaziz Medical City (KAMC). The secondary objective is to describe patients who received HFNO clinically. METHODS: This is a retrospective cohort study of all polymerase chain reaction (PCR)-confirmed COVID-19 patients who require oxygen therapy in KAMC, Jeddah between March 1st, 2020, and December 31st, 2020. Any patients requiring MV on admission were excluded. RESULTS: 259 patients fit the inclusion criteria, and 25.5% of those included received HFNO. The number of non-survivors is 47 (18.1%). Mortality for HFNO, MV, and intensive care unit (ICU) are 30 (45.5%), 31 (60.8%), and 24 (32%), respectively. Their demographic was as follows; 160 were males, with a mean age of 60.93±15.01. Regarding the types of oxygen, low-flow nasal oxygen (LFNO) was administered to 243 out of the 259 patients, 66 received HFNO, 42 received MV, and 49 received other modes of ventilation. Additionally, 43.9% received HFNO escalated to MV. Patients who did not receive HFNO or MV were 178 (68.7%) in total. CONCLUSION: The use of HFNO in COVID-19 patients could show better outcomes than MV in addition to preventing the use of MV. Larger studies are required to determine the efficacy of HFNO in COVID-19 patients.

Persistent Peril: Recurrent Deep Vein Thrombosis and Pulmonary Embolism in a Patient With Protein S Deficiency Despite Optimal Anticoagulation Therapies.

The clotting system has evolved as an adaptive mechanism to prevent blood loss during vascular damage. However, the intricate nature of the clotting cascade and the complexities of human life can sometimes lead to the unnatural activation of this delicate cascade. This can result in blood clot formation within the cardiovascular system, contributing to a wide range of pathological conditions. Abnormal intravascular coagulation most commonly occurs in the deep veins of the lower extremities, and can emboli to other organs, hence, it is termed "venous thromboembolism" (VTE). In this report, we introduce a challenging case of VTE that poses a dilemma for current medical management. The patient with possible protein S deficiency underwent various guideline-directed medical treatments, yet experienced recurrent VTE episodes, including deep vein thrombosis (DVT) and pulmonary embolism (PE), leading to hospital readmissions. This case report sheds light on our challenges in effectively treating VTE.

Case series of dogs with blastomycosis managed with high-flow nasal oxygen therapy (2019-2023): 19 cases.

Objective: To describe the clinical presentation, progression, treatment, and outcome of dogs with blastomycosis treated with high-flow nasal oxygen therapy (HFNOT). Design: Retrospective case review. Setting: University veterinary teaching hospital. Animals: Nineteen client-owned dogs with strongly suspected or confirmed blastomycosis treated with HFNOT. Measurements and main results: The medical records of dogs with strongly suspected or confirmed blastomycosis between October 2019 and May 2023 that received HFNOT were evaluated. Nineteen dogs were included. Nine dogs were started directly on high-flow nasal oxygen therapy. The remaining 10 dogs first received traditional oxygen therapy and were then transitioned to HFNOT 3-142 h later. Of the 19 dogs, 1 survived to discharge from hospital, 12 were euthanized due to progression of disease, and 6 died during the hospitalization period. Conclusions and clinical importance: The prognosis for survival of dogs with severe blastomycosis requiring therapy beyond traditional oxygen methods was poor to grave in this population. This is the first known documented report of HFNOT use in dogs with confirmed or suspected blastomycosis.

High-Flow Nasal Cannula Versus Noninvasive Ventilation as Initial Treatment in Acute Hypoxia: A Propensity Score-Matched Study.

IMPORTANCE: Patients presenting to the emergency department (ED) with hypoxemia often have mixed or uncertain causes of respiratory failure. The optimal treatment for such patients is unclear. Both high-flow nasal cannula (HFNC) and noninvasive ventilation (NIV) are used. OBJECTIVES: We sought to compare the effectiveness of initial treatment with HFNC versus NIV for acute hypoxemic respiratory failure. DESIGN SETTING AND PARTICIPANTS: We conducted a retrospective cohort study of patients with acute hypoxemic respiratory failure treated with HFNC or NIV within 24 hours of arrival to the University of Michigan adult ED from January 2018 to December 2022. We matched patients 1:1 using a propensity score for odds of receiving NIV. MAIN OUTCOMES AND MEASURES: The primary outcome was major adverse pulmonary events (28-d mortality, ventilator-free days, noninvasive respiratory support hours) calculated using a win ratio. RESULTS: A total of 1154 patients were included. Seven hundred twenty-six (62.9%) received HFNC and 428 (37.1%) received NIV. We propensity score matched 668 of 1154 (57.9%) patients. Patients on NIV versus HFNC had lower 28-day mortality (16.5% vs. 23.4%, p = 0.033) and required noninvasive treatment for fewer hours (median 7.5 vs. 13.5, p < 0.001), but had no difference in ventilator-free days (median [interquartile range]: 28 [26, 28] vs. 28 [10.5, 28], p = 0.199). Win ratio for composite major adverse pulmonary events favored NIV (1.38; 95% CI, 1.15-1.65; p < 0.001). CONCLUSIONS AND RELEVANCE: In this observational study of patients with acute hypoxemic respiratory failure, initial treatment with NIV compared with HFNC was associated with lower mortality and fewer composite major pulmonary adverse events calculated using a win ratio. These findings underscore the need for randomized controlled trials to further understand the impact of noninvasive respiratory support strategies.

Designing a Bayesian adaptive clinical trial to evaluate novel mechanical ventilation strategies in acute respiratory failure using integrated nested Laplace approximations.

BACKGROUND: Adaptive trials usually require simulations to determine values for design parameters, demonstrate error rates, and establish the sample size. We designed a Bayesian adaptive trial comparing ventilation strategies for patients with acute hypoxemic respiratory failure using simulations. The complexity of the analysis would usually require computationally expensive Markov Chain Monte Carlo methods but this barrier to simulation was overcome using the Integrated Nested Laplace Approximations (INLA) algorithm to provide fast, approximate Bayesian inference. METHODS: We simulated two-arm Bayesian adaptive trials with equal randomization that stratified participants into two disease severity states. The analysis used a proportional odds model, fit using INLA. Trials were stopped based on pre-specified posterior probability thresholds for superiority or futility, separately for each state. We calculated the type I error and power across 64 scenarios that varied the probability thresholds and the initial minimum sample size before commencing adaptive analyses. Two designs that maintained a type I error below 5%, a power above 80%, and a feasible mean sample size were evaluated further to determine the optimal design. RESULTS: Power generally increased as the initial sample size and the futility threshold increased. The chosen design had an initial recruitment of 500 and a superiority threshold of 0.9925, and futility threshold of 0.95. It maintained high power and was likely to reach a conclusion before exceeding a feasible sample size. CONCLUSIONS: We designed a Bayesian adaptive trial to evaluate novel strategies for ventilation using the INLA algorithm to efficiently evaluate a wide range of designs through simulation.

Using the ROX Index to Predict Treatment Outcome for High-Flow Nasal Cannula and/or Noninvasive Ventilation in Patients With COPD Exacerbations.

BACKGROUND: The ratio of oxygen saturation index (ROX index; or SpO2 /FIO2 /breathing frequency) has been shown to predict risk of intubation after high-flow nasal cannula (HFNC) support among adults with acute hypoxemic respiratory failure primarily due to pneumonia. However, its predictive value for other subtypes of respiratory failure is unknown. This study investigated whether the ROX index predicts liberation from HFNC or noninvasive ventilation (NIV), intubation with mechanical ventilation, or death in adults admitted for respiratory failure due to an exacerbation of COPD. METHODS: We performed a retrospective study of 260 adults hospitalized with a COPD exacerbation and treated with HFNC and/or NIV (continuous or bi-level). ROX index scores were collected at treatment initiation and predefined time intervals throughout HFNC and/or NIV treatment or until the subject was intubated or died. A ROX index score of ≥ 4.88 was applied to the cohort to determine if the same score would perform similarly in this different cohort. Accuracy of the ROX index was determined by calculating the area under the receiver operator curve. RESULTS: A total of 47 subjects (18%) required invasive mechanical ventilation or died while on HFNC/NIV. The ROX index at treatment initiation, 1 h, and 6 h demonstrated the best prediction accuracy for avoidance of invasive mechanical ventilation or death (area under the receiver operator curve 0.73 [95% CI 0.66-0.80], 0.72 [95% CI 0.65-0.79], and 0.72 [95% CI 0.63-0.82], respectively). The optimal cutoff value for sensitivity (Sn) and specificity (Sp) was a ROX index score > 6.88 (sensitivity 62%, specificity 57%). CONCLUSIONS: The ROX index applied to adults with COPD exacerbations treated with HFNC and/or NIV required higher scores to achieve similar prediction of low risk of treatment failure when compared to subjects with hypoxemic respiratory failure/pneumonia. ROX scores < 4.88 did not accurately predict intubation or death.

A Prospective Observational Study Comparing Oxygen Saturation/Fraction of Inspired Oxygen Ratio with Partial Pressure of Oxygen in Arterial Blood/Fraction of Inspired Oxygen Ratio among Critically Ill Patients Requiring Different Modes of Oxygen Supplementation in Intensive Care Unit.

Background: Intensive care unit (ICU) patients face a significant rise in mortality rates due to acute hypoxemic respiratory failure (AHRF). The diagnosis of AHRF is based on the PF ratio, but it has limitations in resource-constrained settings. Instead, the Kigali modification suggests using the oxygen saturation/fraction of inspired oxygen (SF) ratio. This study aims to correlate SF ratio and arterial oxygen pressure (PF) ratio in critically ill adults with hypoxemic respiratory failure, who required O2 therapy through different modes of oxygen supplementation. Materials and methods: In an ICU, a prospective observational study included 125 adult AHRF patients receiving oxygen therapy, with data collected on FiO2, PaO2, and SpO2. The SF ratio and PF ratio were calculated, and their correlation was assessed using statistical analysis. The receiver operator characteristics (ROC) curve analysis was conducted to assess the diagnostic precision of the SF ratio in identifying AHRF. Results: Data from a total of 250 samples were collected. The study showed a positive correlation (r = 0.622) between the SF ratio and the PF ratio. The SF threshold values of 252 and 321 were established for PF values of 200 and 300, respectively, featuring a sensitivity of 69% and specificity of 95%. Furthermore, it is worth noting that the PF ratio and SF ratio are interchangeable, regardless of the type of oxygen therapy, as the median values of both the PF ratio and SF ratio displayed statistical significance (p < 0.01) in both acidosis and alkalosis conditions. Conclusion: For patients with AHRF, the noninvasive SF ratio can effectively serve as a substitute for the invasive PF ratio across all oxygen supplementation modes. How to cite this article: Alur TR, Iyer SS, Shah JN, Kulkarni S, Jedge P, Patil V. A Prospective Observational Study Comparing Oxygen Saturation/Fraction of Inspired Oxygen Ratio with Partial Pressure of Oxygen in Arterial Blood/Fraction of Inspired Oxygen Ratio among Critically Ill Patients Requiring Different Modes of Oxygen Supplementation in Intensive Care Unit. Indian J Crit Care Med 2024; 28(3):251-255.

Diagnosis and Epidemiology of Acute Respiratory Failure.

Acute respiratory failure is a common clinical finding caused by insufficient oxygenation (hypoxemia) or ventilation (hypocapnia). Understanding the pathophysiology of acute respiratory failure can help to facilitate recognition, diagnosis, and treatment. The cause of acute respiratory failure can be identified through utilization of physical examination findings, laboratory analysis, and chest imaging.

Association between the ROX index and mortality in patients with acute hypoxemic respiratory failure: a retrospective cohort study.

BACKGROUND: Although ROX index is frequently used to assess the efficacy of high-flow nasal cannula treatment in acute hypoxemic respiratory failure (AHRF) patients, the relationship between the ROX index and the mortality remains unclear. Therefore, a retrospective cohort study was conducted to evaluate the ability of the ROX index to predict mortality risk in patients with AHRF. METHOD: Patients diagnosed with AHRF were extracted from the MIMIC-IV database and divided into four groups based on the ROX index quartiles. The primary outcome was 28-day mortality, while in-hospital mortality and follow-up mortality were secondary outcomes. To investigate the association between ROX index and mortality in AHRF patients, restricted cubic spline curve and COX proportional risk regression were utilized. RESULT: A non-linear association (L-shaped) has been observed between the ROX index and mortality rate. When the ROX index is below 8.28, there is a notable decline in the 28-day mortality risk of patients as the ROX index increases (HR per SD, 0.858 [95%CI 0.794-0.928] P < 0.001). When the ROX index is above 8.28, no significant association was found between the ROX index and 28-day mortality. In contrast to the Q1 group, the mortality rates in the Q2, Q3, and Q4 groups had a substantial reduction (Q1 vs. Q2: HR, 0.749 [0.590-0.950] P = 0.017; Q3: HR, 0.711 [0.558-0.906] P = 0.006; Q4: HR, 0.641 [0.495-0.830] P < 0.001). CONCLUSION: The ROX index serves as a valuable predictor of mortality risk in adult patients with AHRF, and that a lower ROX index is substantially associated with an increase in mortality.

Immunomodulators for immunocompromised patients hospitalized for COVID-19: a meta-analysis of randomized controlled trials.

Background: Although immunomodulators have established benefit against the new coronavirus disease (COVID-19) in general, it is uncertain whether such agents improve outcomes without increasing the risk of secondary infections in the specific subgroup of previously immunocompromised patients. We assessed the effect of immunomodulators on outcomes of immunocompromised patients hospitalized for COVID-19. Methods: The protocol was prospectively registered with PROSPERO (CRD42022335397). MEDLINE, Cochrane Central Register of Controlled Trials and references of relevant articles were searched up to 01-06-2022. Authors of potentially eligible randomized controlled trials were contacted to provide data on immunocompromised patients randomized to immunomodulators vs control (i.e., placebo or standard-of-care). Findings: Eleven randomized controlled trials involving 397 immunocompromised patients hospitalized for COVID-19 were included. Ten trials had low risk of bias. There was no difference between immunocompromised patients randomized to immunomodulators vs control regarding mortality [30/182 (16.5%) vs 41/215 (19.1%); RR 0.93, 95% CI 0.61-1.41; p = 0.74], secondary infections (RR 1.00, 95% CI 0.64-1.58; p = 0.99) and change in World Health Organization ordinal scale from baseline to day 15 (weighed mean difference 0.27, 95% CI -0.09-0.63; p = 0.15). In subgroup analyses including only patients with hematologic malignancy, only trials with low risk of bias, only trials administering IL-6 inhibitors, or only trials administering immunosuppressants, there was no difference between comparators regarding mortality. Interpretation: Immunomodulators, compared to control, were not associated with harmful or beneficial outcomes, including mortality, secondary infections, and change in ordinal scale, when administered to immunocompromised patients hospitalized for COVID-19. Funding: Hellenic Foundation for Research and Innovation.

IgA-Dominant Staphylococcus-Associated Glomerulonephritis: An Uncommon Complication of Intravenous Drug Use.

A 24-year-old female with a history of intravenous heroin use presented with two weeks of chills, myalgias, and cough and was found to be in acute hypoxemic respiratory failure. Subsequent workup revealed the presence of bilateral septic pulmonary emboli and tricuspid valve endocarditis. Several weeks into her hospitalization, she developed periorbital edema and laboratory testing revealed she had developed acute renal failure and nephrotic range proteinuria. A renal biopsy confirmed the diagnosis of IgA-dominant Staphylococcus-associated glomerulonephritis (IgA-SAGN). Early recognition of this newly recognized variant of glomerulonephritis is paramount, as improper treatment may lead to catastrophic consequences.

Urgent Cesarean Section in a Patient on Venovenous Extracorporeal Membrane Oxygenation.

A G7P6 40-year-old female at 20 weeks gestation, with a history of polysubstance use disorder and hepatitis C, presented to the emergency department with severe shortness of breath and hypoxia requiring intubation. After a thorough workup, she was diagnosed with aspiration pneumonitis and was treated with a course of antibiotics. After progressing well, she was soon extubated and transferred to a subacute rehabilitation facility (SAR). There, she acutely decompensated, requiring readmission, reintubation, and venovenous extracorporeal membrane oxygenation (ECMO) cannulation. After a brief period of improvement, the patient became increasingly unstable with hypotension, anemia, and downtrending fibrinogen. Bedside imaging indicated a possible placental abruption. After extensive discussion among the care teams and patient's healthcare proxy, an urgent cesarean section was performed. Although the fetus was determined to be nonviable, the patient tolerated the procedure well and was eventually decannulated from ECMO and transferred to a SAR.

Optimal timing for awake prone positioning in Covid-19 patients: Insights from an observational study from two centers.

BACKGROUND: The widespread application and interest in awake prone positioning stems from its ease and availability and its ability to enhance patients' oxygenation. Nevertheless, due to the absence of consensus over the regimen of awake prone positioning, the efficacy of awake prone positioning remains uncertain. OBJECTIVE: To explore the optimal regimen for awake prone positioning, including the timing of initiation, ideal daily duration, and strategies for improving patient comfort and encouraging adherence. DESIGN: Retrospective observational study. SETTING(S): Two university-affiliated hospitals in Shanghai. PARTICIPANTS: Between December 2022 and February 2023, a total of 475 patients with COVID-19-related pneumonia who received awake prone positioning were observed. METHODS: The data were collected from the hospital's electronic medical record system. The differentiation efficiency of peripheral blood oxygen saturation [SpO2]:fractional oxygen concentration in inspired air [FiO2] ratio at first awake prone positioning for different outcomes was tested by the area under the receiver operating characteristic curve. The Cox proportional hazard regression model was used to analyze the relationship between time to occurrence of 28-day outcomes and collected variables. Kaplan-Meier curves were plotted with the percentage of 28-day outcomes according to the SpO2:FiO2 ratio at first awake prone positioning after controlling covariates through Cox regression. RESULTS: The best efficiency in predicting patient outcomes was achieved when the cutoff SpO2:FiO2 ratio at first awake prone positioning was 200. Patients with a reduced SpO2:FiO2 ratio (≤200) experienced more adverse respiratory outcomes (RR = 5.42, 95%CI [3.35, 8.76], p < 0·001) and higher mortality (RR = 16.64, 95%CI [5.53, 50.13], p < 0.001). Patients with a SpO2:FiO2 ratio of ≥200 at first awake prone positioning, longer duration between first awake prone positioning and admission, more awake prone positioning days, and better awake prone positioning completion were significantly protected from 28-day adverse respiratory outcomes and mortality. CONCLUSIONS: Initiating awake prone positioning with a SpO2:FiO2 ratio exceeding 200, increasing the number of awake prone positioning days, prolonging the time between first awake prone positioning and admission, and achieving better completion of awake prone positioning were found to be significantly associated with reduced adverse respiratory outcomes and mortality. REGISTRATION: ClinicalTrials.gov; No.: NCT05795751; URL: www. CLINICALTRIALS: gov.

The Effect of Lower Tidal Volume Ventilation Facilitated by Extracorporeal Carbon Dioxide Removal Compared With Conventional Lung Protective Ventilation on Cardiac Function.

OBJECTIVES: Lower tidal volume ventilation (targeting 3 mL/kg predicted body weight, PBW) facilitated by extracorporeal carbon dioxide removal (ECCO2R) has been investigated as a potential therapy for acute hypoxemic respiratory failure (AHRF) in the pRotective vEntilation with veno-venouS lung assisT in respiratory failure (REST) trial. We investigated the effect of this strategy on cardiac function, and in particular the right ventricle. DESIGN: Substudy of the REST trial. SETTING: Nine U.K. ICUs. PATIENTS: Patients with AHRF (Pao2/Fio2 < 150 mm Hg [20 kPa]). INTERVENTION: Transthoracic echocardiography and N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurements were collected at baseline and postrandomization in patients randomized to ECCO2R or usual care. MEASUREMENTS: The primary outcome measures were a difference in tricuspid annular plane systolic excursion (TAPSE) on postrandomization echocardiogram and difference in NT-proBNP postrandomization. RESULTS: There were 21 patients included in the echocardiography cohort (ECCO2R, n = 13; usual care, n = 8). Patient characteristics were similar in both groups at baseline. Median (interquartile range) tidal volumes were lower in the ECCO2R group compared with the usual care group postrandomization; 3.6 (3.1-4.2) mL/kg PBW versus 5.2 (4.9-5.7) mL/kg PBW, respectively (p = 0.01). There was no difference in the primary outcome measure of mean (sd) TAPSE in the ECCO2R and usual care groups postrandomization; 21.3 (5.4) mm versus 20.1 (3.2) mm, respectively (p = 0.60). There were 75 patients included in the NT-proBNP cohort (ECCO2R, n = 36; usual care, n = 39). Patient characteristics were similar in both groups at baseline. Median (interquartile range [IQR]) tidal volumes were lower in the ECCO2R group than the usual care group postrandomization; 3.8 (3.3-4.2) mL/kg PBW versus 6.7 (5.8-8.1) mL/kg PBW, respectively (p < 0.0001). There was no difference in median (IQR) NT-proBNP postrandomization; 1121 (241-5370) pg/mL versus 1393 (723-4332) pg/mL in the ECCO2R and usual care groups, respectively (p = 0.30). CONCLUSIONS: In patients with AHRF, a reduction in tidal volume facilitated by ECCO2R, did not modify cardiac function.

Effectiveness and safety of awake prone positioning in COVID-19-related acute hypoxaemic respiratory failure: an overview of systematic reviews.

OBJECTIVE: To evaluate and summarize systematic reviews of the effects and safety of awake prone positioning for COVID-19-related acute hypoxaemic respiratory failure. METHODS: A comprehensive search was conducted on PubMed, Embase, the Cochrane Library, Web of Science, CNKI, CSPD, CCD and CBM from their inception to March 28, 2023. Systematic reviews (SRs) of awake prone positioning (APP) for COVID-19-related acute hypoxaemic respiratory failure in adults were included. Two reviewers screened the eligible articles, and four reviewers in pairs extracted data and assessed the methodological quality/certainty of the evidence of all included SRs by AMSTAR 2 and GRADE tools. The overlap of primary studies was measured by calculating corrected covered areas. Data from the included reviews were synthesized with a narrative description. RESULTS: A total of 11 SRs were included. The methodological quality of SRs included 1 "High", 4 "Moderate", 2 "Low" and 4 "Critically low" by AMSTAR 2. With the GRADE system, no high-quality evidence was found, and only 14 outcomes provided moderate-quality evidence. Data synthesis of the included SR outcomes showed that APP reduced the risk of requiring intubation (11 SRs) and improving oxygenation (3 SRs), whereas reduced significant mortality was not found in RCT-based SRs. No significant difference was observed in the incidence of adverse events between groups (8 SRs). The corrected covered area index was 27%, which shows very high overlap among studies. CONCLUSION: The available SRs suggest that APP has benefits in terms of reducing intubation rates and improving oxygenation for COVID-19-related acute hypoxemic respiratory failure, without an increased risk of adverse events. The conclusion should be treated with caution because of the generally low quality of methodology and evidence. TRIAL REGISTRATION: The protocol for this review was registered with PROSPERO: CRD42023400986. Registered 15 April 2023.

Low Tidal Volume Ventilation Is Poorly Implemented for Patients in North American and United Kingdom ICUs Using Electronic Health Records.

BACKGROUND: Low tidal volume ventilation (LTVV; < 8 mL/kg predicted body weight [PBW]) is a well-established standard of care associated with improved outcomes. This study used data collated in multicenter electronic health record ICU databases from the United Kingdom and the United States to analyze the use of LTVV in routine clinical practice. RESEARCH QUESTION: What factors are associated with adherence to LTVV in the United Kingdom and North America? STUDY DESIGN: This was a retrospective, multicenter study across the United Kingdom and United States of patients who were mechanically ventilated. METHODS: Factors associated with adherence to LTVV were assessed in all patients in both databases who were mechanically ventilated for > 48 h. We observed trends over time and investigated whether LTVV was associated with patient outcomes (30-day mortality and duration of ventilation) and identified strategies to improve adherence to LTVV. RESULTS: A total of 5,466 (Critical Care Health Informatics Collaborative [CCHIC]) and 7,384 electronic ICU collaborative research database [eICU-CRD] patients were ventilated for > 48 h and had data of suitable quality for analysis. The median tidal volume (VT) values were 7.48 mL/kg PBW (CCHIC) and 7.91 mL/kg PBW (eICU-CRD). The patients at highest risk of not receiving LTVV were shorter than 160 cm (CCHIC) and 165 cm (eICU-CRD). Those with BMI > 30 kg/m2 (CCHIC OR, 1.9 [95% CI, 1.7-2.13]; eICU-CRD OR, 1.61 [95% CI, 1.49-1.75]) and female patients (CCHIC OR, 2.39 [95% CI, 2.16-2.65]; eICU-CRD OR, 2.29 [95% CI, 2.26-2.31]) were at increased risk of having median VT > 8 mL/kg PBW. Patients with median VT < 8 mL/kg PBW had decreased 30-day mortality in the CCHIC database (CCHIC cause-specific hazard ratio, 0.86 [95% CI, 0.76-0.97]; eICU-CRD cause-specific hazard ratio, 0.9 [95% CI, 0.86-1.00]). There was a significant reduction in VT over time in the CCHIC database. INTERPRETATION: There has been limited implementation of LTVV in routine clinical practice in the United Kingdom and the United States. VT > 8 mL/kg PBW was associated with worse patient outcomes.