COVID-19 ARDS: Points to Be Considered in Mechanical Ventilation and Weaning

Association of biomarkers with successful ventilatory weaning in COVID-19 patients: an observational study

OBJECTIVE

To evaluate the association of biomarkers with successful ventilatory weaning in COVID-19 patients.

METHODS

An observational, retrospective, and single-center study was conducted between March 2020 and April 2021. C-reactive protein, total lymphocytes, and the neutrophil/lymphocyte ratio were evaluated during attrition and extubation, and the variation in these biomarker values was measured. The primary outcome was successful extubation. ROC curves were drawn to find the best cutoff points for the biomarkers based on sensitivity and specificity. Statistical analysis was performed using logistic regression.

RESULTS

Of the 2,377 patients admitted to the intensive care unit, 458 were included in the analysis, 356 in the Successful Weaning Group and 102 in the Failure Group. The cutoff points found from the ROC curves were -62.4% for C-reactive protein, +45.7% for total lymphocytes, and -32.9% for neutrophil/lymphocyte ratio. These points were significantly associated with greater extubation success. In the multivariate analysis, only C-reactive protein variation remained statistically significant (OR 2.6; 95%CI 1.51 - 4.5; p < 0.001).

CONCLUSION

In this study, a decrease in C-reactive protein levels was associated with successful extubation in COVID-19 patients. Total lymphocytes and the neutrophil/lymphocyte ratio did not maintain the association after multivariate analysis. However, a decrease in C-reactive protein levels should not be used as a sole variable to identify COVID-19 patients suitable for weaning; as in our study, the area under the ROC curve demonstrated poor accuracy in discriminating extubation outcomes, with low sensitivity and specificity.

The intervention of artificial intelligence to improve the weaning outcomes of patients with mechanical ventilation: Practical applications in the medical intensive care unit and the COVID-19 intensive care unit: A retrospective study

Patients admitted to intensive care units (ICU) and receiving mechanical ventilation (MV) may experience ventilator-associated adverse events and have prolonged ICU length of stay (LOS). We conducted a survey on adult patients in the medical ICU requiring MV. Utilizing big data and artificial intelligence (AI)/machine learning, we developed a predictive model to determine the optimal timing for weaning success, defined as no reintubation within 48 hours. An interdisciplinary team integrated AI into our MV weaning protocol. The study was divided into 2 parts. The first part compared outcomes before AI (May 1 to Nov 30, 2019) and after AI (May 1 to Nov 30, 2020) implementation in the medical ICU. The second part took place during the COVID-19 pandemic, where patients were divided into control (without AI assistance) and intervention (with AI assistance) groups from Aug 1, 2022, to Apr 30, 2023, and we compared their short-term outcomes. In the first part of the study, the intervention group (with AI, n = 1107) showed a shorter mean MV time (144.3 hours vs 158.7 hours, P = .077), ICU LOS (8.3 days vs 8.8 days, P = .194), and hospital LOS (22.2 days vs 25.7 days, P = .001) compared to the pre-intervention group (without AI, n = 1298). In the second part of the study, the intervention group (with AI, n = 88) exhibited a shorter mean MV time (244.2 hours vs 426.0 hours, P = .011), ICU LOS (11.0 days vs 18.7 days, P = .001), and hospital LOS (23.5 days vs 40.4 days, P < .001) compared to the control group (without AI, n = 43). The integration of AI into the weaning protocol led to improvements in the quality and outcomes of MV patients.

Using Artificial Intelligence to Predict Mechanical Ventilation Weaning Success in Patients with Respiratory Failure, Including Those with Acute Respiratory Distress Syndrome

The management of mechanical ventilation (MV) remains a challenge in intensive care units (ICUs). The digitalization of healthcare and the implementation of artificial intelligence (AI) and machine learning (ML) has significantly influenced medical decision-making capabilities, potentially enhancing patient outcomes. Acute respiratory distress syndrome, an overwhelming inflammatory lung disease, is common in ICUs. Most patients require MV. Prolonged MV is associated with an increased length of stay, morbidity, and mortality. Shortening the MV duration has both clinical and economic benefits and emphasizes the need for better MV weaning management. AI and ML models can assist the physician in weaning patients from MV by providing predictive tools based on big data. Many ML models have been developed in recent years, dealing with this unmet need. Such models provide an important prediction regarding the success of the individual patient's MV weaning. Some AI models have shown a notable impact on clinical outcomes. However, there are challenges in integrating AI models into clinical practice due to the unfamiliar nature of AI for many physicians and the complexity of some AI models. Our review explores the evolution of weaning methods up to and including AI and ML as weaning aids.

Factors Affecting Mechanical Ventilator Weaning Success and 28-Day Survival Among Patients With Acute Respiratory Distress Syndrome Secondary to COVID-19

Introduction

The process of weaning patients off mechanical ventilation (MV) is difficult and complex. Critical care nurses must maintain continuity of care for patients undergoing MV weaning, assess patients' overall condition, and meet patients' needs.

Objectives

The study aimed to explore clinical factors of MV weaning success and 28-day survival among patients with acute respiratory distress syndrome secondary to COVID-19.

Methods

This prospective observational study was conducted on 90 newly admitted patients in the general intensive care unit Assiut Univeristy Main Hospital in Egypt from October 2021 to March 2022. The researchers applied a standard weaning protocol for all of the patients in this study and then assessed the outcome variables: success or failure of weaning trials from a mechanical ventilator, and 28-day survival.

Results

In total, 50 (55.6%) patients were successfully weaned from MV, and 45 (50%) patients survived at 28 days. In a multivariate regression analysis, dynamic compliance (OR, 1.115; 95% CI, 1.010-1.230, p = .031*), lymphocyte count (OR, 3.025; 95% CI, 1.322-6.923, p = .009*), urine output (OR, 1.002; 95% CI, 1.001-1.004, p = .002*), and alanine aminotransferase (ALT; OR, 0.993; 95% CI, 0.988-0.999, p = .017*) were significantly associated with weaning success. In addition, age (OR, 1.058; 95% CI, 1.015-1.102; p = .007*), lymphocyte count (OR, 3.304; 95% CI, 1.348-8.100; p = .009*), urine output (OR, 1.003; 95% CI, 1.001-1.004; p = .001*), and ALT (OR, 0.994; 95% CI, 0.989-0.99, p = .015*) were significantly associated with survival at 28 days.

Conclusion

Dynamic lung compliance, lymphocyte count, urine output, and ALT were found to be predictive parameters that may affect the success of weaning off MV. Additionally, it was found that age, lymphocyte count, urine output, and ALT are predictors of survival at 28 days. We recommend further studies with larger, more systematic samples and complete follow-up, focusing on pulmonary function and quality of life in postweaning patients with acute respiratory distress syndrome.

Acute liver injury in COVID-19 patients hospitalized in the intensive care unit: Narrative review

In recent years, humanity has been confronted with a global pandemic due to coronavirus disease 2019 (COVID-19), which has caused an unprecedented health and economic crisis worldwide. Apart from the respiratory symptoms, which are considered the principal manifestations of COVID-19, it has been recognized that COVID-19 constitutes a systemic inflammatory process affecting multiple organ systems. Across the spectrum of organ involvement in COVID-19, acute liver injury (ALI) has been gradually gaining increasing attention by the international scientific community. COVID-19 associated liver impairment can affect a considerable proportion of COVID-19 patients and seems to correlate with the severity of the disease course. Indeed, COVID-19 patients hospitalized in the intensive care unit (ICU) run a greater risk of developing ALI due to the severity of their clinical condition and in the context of multi-organ failure. The putative pathophysiological mechanisms of COVID-19 induced ALI in ICU patients remain poorly understood and appear to be multifactorial in nature. Several theories have been proposed to explain the occurrence of ALI in the ICU setting, such as hypoperfusion and ischemia due to hemodynamic instability, passive liver congestion as a result of congestive heart failure, ischemia-reperfusion injury, hypoxia due to respiratory failure, mechanical ventilation itself, sepsis and septic shock, cytokine storm, endotheliitis with concomitant coagulopathy, drug-induced liver injury, parenteral nutrition and direct cytopathic viral effect. It should be noted that no specific therapy for COVID-19 induced ALI exists. Therefore, the therapeutic approach lies in preventive measures and is exclusively supportive once ALI ensues. The aim of the current review is to scrutinize the existing evidence on COVID-19 associated ALI in ICU patients, explore its clinical implications, shed light on the underlying pathophysiological mechanisms and propose potential therapeutic approaches. Ongoing research on the particular scientific field will further elucidate the pathophysiology behind ALI and address unresolved issues, in the hope of mitigating the tremendous health consequences imposed by COVID-19 on ICU patients.

Delayed onset phlegmasia cerulea dolens post-SARS-CoV-2 infection treated with minimally invasive clot retrieval technology

Coronavirus disease 2019 is associated with a significant venous thromboembolic risk. Phlegmasia cerulean dolens is a severe form of deep vein thrombosis that can lead to acute limb ischemia. In this report, we present a 58-year-old woman who developed a delayed-onset left lower extremity phlegmasia cerulean dolens 8 weeks after coronavirus disease 2019 onset that led to compartment syndrome and acute limb ischemia from external compression of the arterial vasculature from edematous muscle. The patient received an emergent minimally invasive percutaneous mechanical thrombectomy and four-compartment fasciotomy, resulting in adequate perfusion and ultimately made a full recovery.

Usefulness of KL-6 for Predicting Clinical Outcomes in Hospitalized COVID-19 Patients

Background: Krebs von den Lungen 6 (KL-6) is a novel biomarker for interstitial lung disease, and it reflects acute lung injury. We explored the usefulness of KL-6 to predict clinical outcomes in hospitalized coronavirus disease 2019 (COVID-19) patients. Methods: In a total of 48 hospitalized COVID-19 patients, KL-6 levels were measured using the HISCL KL-6 assay (Sysmex, Kobe, Japan) with the HISCL 5000 automated analyzer (Sysmex). Clinical outcomes (intensive care unit [ICU] admission, ventilator use, extracorporeal membrane oxygenation [ECMO] use, and 30-day mortality) were analyzed according to KL-6 percentiles. Age, initial KL-6 level, Charlson comorbidity index (CCI), and critical disease were compared using the receiver operating characteristic (ROC) curve and Kaplan-Meier methods for clinical outcomes. Results: KL-6 quartiles were associated with ICU admission, ventilator use, and ECMO use (all p < 0.05), except 30-day mortality (p = 0.187). On ROC curve analysis, initial KL-6 level predicted ICU admission, ventilator use, and ECMO use significantly better than age, CCI, and critical disease (all p < 0.05); age, initial KL-6 level, CCI, and critical disease predicted 30-day mortality comparably. On Kaplan−Meier survival analysis, hazard ratios (95% confidence interval) were 4.8 (1.2−19.3) for age, 4.7 (1.1−21.6) for initial KL-6 level, 3.9 (0.9−16.2) for CCI, and 2.1 (0.5−10.3) for critical disease. Conclusions: This study demonstrated that KL-6 could be a useful biomarker to predict clinical outcomes in hospitalized COVID-19 patients. KL-6 may contribute to identifying COVID-19 patients requiring critical care, including ICU admission and ventilator and/or ECMO use.

The Feasibility of Percutaneous Dilatational Tracheostomy in Immunosuppressed ICU Patients with or without Thrombocytopenia

Background

Percutaneous dilatational tracheostomy (PDT) has become the preferred method in several intensive care units (ICUs), but data on PDT performed in immunosuppressed and thrombocytopenic patients are scarce. This study aimed to analyze the feasibility of PDT in immunosuppressed and thrombocytopenic patients compared to conventional open surgical tracheostomy (OST).

Methods

We retrospectively analyzed the charts of patients who underwent PDT or OST between May 2017 and November 2020. Our outcomes were stoma site infections and bleeding complications.

Results

63 patients underwent PDT, and 21 patients underwent OST. Distribution of gender ratio, age, SAPS II, time of ventilation before tracheostomy, and preexisting hematooncological diseases was comparable between the two groups. After allogeneic stem cell transplantation (alloSCT), patients were more likely to undergo PDT than OST (p=0.033). The PDT cohort suffered from mucositis more frequently (p=0.043). There were no significant differences in leucocyte or platelet count on the tracheostomy day. Patients with coagulation disorders and patients under immunosuppression were distributed equally among both groups. Stoma site infection was documented in five cases in PDT and eight cases in the OST group. Moderate infections were remarkably increased in the OST group. Smears were positive in six cases in the PDT group; none of these patients had local infection signs. In the OST group, smears were positive in four cases; all had signs of a stroma site infection. Postprocedural bleedings occurred in eight cases (9.5%) and were observed significantly more often in the OST group (p=0.001), leading to emergency surgery in one case of the OST group.

Conclusion

PDT is a feasible and safe procedure in a predominantly immunosuppressed and thrombocytopenic patient cohort without an increased risk for stoma site infections or bleeding complications.

Efficacy and Safety of Extracorporeal Membrane Oxygenation in Patients under Mechanical Ventilation with COVID-19 and Severe Acute Respiratory Distress Syndrome: A Health Technology Assessment

We aimed to assess the efficacy and safety of extracorporeal membrane oxygenation (ECMO) in patients under mechanical ventilation with COVID-19 and severe acute respiratory distress syndrome (ARDS). A systematic review of the literature published in PubMed, Cochrane Library and LILACS databases, was performed. A manual search was also conducted using the reference lists of the studies included in the full-text assessment, as well as a grey-literature search on Google. Additionally, websites of state institutions and organizations developing clinical practice guidelines and health technology assessments were reviewed. The ClinicalTrials.gov website was screened along with the websites of the International Clinical Trial Registry Platform and the National Registry of Health Research Projects of the Peruvian National Institute of Health. No restrictions were applied in terms of language, time, or country. A total of 13 documents were assessed, which included 7 clinical practice guidelines, 3 health technology assessments, 1 systematic review, 1 randomized clinical trial, and 1 observational study. A critical appraisal was conducted for each document. After this, we considered that the currently available evidence is insufficient for a conclusion supporting the use of ECMO in patients under mechanical ventilation with severe ARDS associated to COVID-19 in terms of mortality, safety, and quality of life.

Ventilator-associated pneumonia in critically ill patients with COVID-19 infection, a narrative review

COVID pneumonitis can cause patients to become critically ill. They may require intensive care and mechanical ventilation. Ventilator-associated pneumonia is a concern. This review aims to discuss the topic of ventilator-associated pneumonia in this group. Several reasons have been proposed to explain the elevated rates of VAP in critically ill COVID patients compared to non-COVID patients. Extrinsic factors include understaffing, lack of PPE and use of immunomodulating agents. Intrinsic factors include severe parenchymal damage, immune dysregulation, along with pulmonary vascular endothelial inflammation and thrombosis. The rate of VAP has been reported at 45.4%, with an ICU mortality rate of 42.7%. Multiple challenges to diagnosis exist. Other conditions such as acute respiratory distress syndrome, pulmonary oedema and atelectasis can present with similar features. Frequent growth of gram-negative bacteria has been shown in multiple studies, with particularly high rates of pseudomonas aeruginosa. The rate of invasive pulmonary aspergillosis has been reported at 4–30%. We would recommend the use of invasive techniques when possible. This will enable de-escalation of antibiotics as soon as possible, decreasing overuse. It is also important to keep other possible causes of ventilator-associated pneumonia in mind, such as COVID-19 associated pulmonary aspergillosis, cytomegalovirus, etc. Diagnostic tests such as galactomannan and B-D-glucan should be considered. These patients may face a long treatment course, with risk of re-infection, along with prolonged weaning, which carries its own long-term consequences.

Effects in vitro and in vivo of hesperidin administration in an experimental model of acute lung inflammation

Mechanical ventilation (MV) is a tool used in critical patient care. However, it can trigger inflammatory and oxidative processes capable of causing or aggravating lung injuries, which is known as ventilator-induced lung injury (VILI). Hesperidin is a flavonoid with antioxidant and anti-inflammatory properties in various diseases. The role of hesperidin in the process triggered by MV is poorly studied. Thus, we hypothesize hesperidin could protect the lung of mice submitted to mechanical ventilation. For that, we evaluated cell viability and reactive oxygen species (ROS) formation in macrophages using different hesperidin concentrations. We observed hesperidin did not reduce cell viability, however; it attenuated the production of intracellular ROS in cells stimulated with lipopolysaccharide (LPS). We further evaluated the effects of hesperidin in vivo in animals submitted to MV. In the bronchoalveolar lavage fluid, there were higher levels of macrophage, lymphocyte and neutrophil counts in animals submitted to MV, indicating an inflammatory process. In the lung tissue, MV induced oxidative damage and increased myeloperoxidase activity, though the antioxidant enzyme activity decreased. MV also induced the production of the inflammatory mediators CCL-2, TNF-α and IL-12. Pretreatment with hesperidin resulted in less recruitment of inflammatory cells to the airways and less oxidative damage. Also, it reduced the formation of CCL-2 and IL-12. Our results show pretreatment with hesperidin can protect the lungs of mice submitted to mechanical ventilation by modulating the inflammatory response and redox imbalance and may act to prevent MV injury.