Correlation and Prognostic Significance of Oxygenation Indices in Invasively Ventilated Adults (OXIVA-CARDS) with COVID-19-associated ARDS: A Retrospective Study.

Background: Oxygenation index [OI = (MAP × FiO2 × 100)/PaO2] assesses the severity of hypoxic respiratory failure. Oxygen saturation index [OSI = (MAP × FiO2 × 100)/SpO2] is a noninvasive method to assesses the severity of hypoxic respiratory failure. Conventionally used PaO2/FiO2 (P/F) ratio to measure the severity of ARDS requires arterial blood gas (ABG) sampling. It tenders limited prognostic information mandating the need for better markers. Oxygenation index (needs arterial sampling) and OSI (a noninvasive method) are substitutes to provide mortality information in ARDS patients. We evaluated the correlation between P/F, OI, and OSI in invasively ventilated COVID-19 ARDS patients (C-ARDS) and looked at its relationship with mortality. Patients and methods: A retrospective study of invasively ventilated C-ARDS >18 years of age managed in COVID ICU. Ventilator settings (FiO2, mean airway pressure), pulse oximetry (SpO2), and ABG values (PaO2) were simultaneously noted at the time of sample collection. Patient outcomes (alive and deceased) were documented. Differences in parameters between survivors and nonsurvivors were assessed using independent sample t-test. Receiver operating characteristic (ROC) analysis with Youden's index was used to identify cutoff values to determine survival. Results: A total of 1557 measurements for 203 patients were collected over the maximum duration of 21 days after ventilation. About 147 (72.4%) were males and 56 (27.6%) were females. On day one of ventilation, 161 (79.3%) had P/F ratio <200, 28 (13.8%) had P/F ratio between 200 and 300, and 14 (6.9%) had P/F ratio >300. There was a linear relationship between P/F ratio and OSI (r = -0.671), P/F and OI (r = -0.753), and OSI and OI (r = 0.893) (p < 0.001). After natural log transform, the correlation between these factors became stronger [P/F ratio and OSI (r = -0.797), PF and OI (r = -0.949), and OSI and OI (r = 0.902) (p < 0.001)]. About 74 (36.5%) patients survived. Survivors had significantly higher P/F ratio as compared with nonsurvivors (p < 0.05). Oxygen saturation index and OI were significantly lower in survivors as compared with nonsurvivors. Based on day-1 reading, a higher OSI (AUC = 0.719, 95% CI = 0.648-0.790) and OI (AUC = 0.752. 95% CI = 0.684-0.819) significantly can predict mortality. On the other hand, a higher P/F ratio can predict survival (AUC = 0.734, 95% CI = 0.664-0.805). P/F ratio of 160 on day 1 can predict survival. Oxygen saturation index values above 10.4% and OI above 13.5% were the cutoff derived for day 1 values to predict mortality. Conclusion: Noninvasive OSI can be used to assess the severity of hypoxic respiratory failure in C-ARDS without arterial access in resource-limited settings. Oxygen saturation index can noninvasively provide prognostic information in invasively ventilated C-ARDS patients. How to cite this article: Vadi S, Suthar D, Sanwalka N. Correlation and Prognostic Significance of Oxygenation Indices in Invasively Ventilated Adults (OXIVA-CARDS) with COVID-19-associated ARDS: A Retrospective Study. Indian J Crit Care Med 2023;27(11):801-805.

Pediatric Acute Respiratory Distress Syndrome in COVID-19 Pandemic: Is it the Puzzle of the Century?

Bhowmick R, Gulla KM. Pediatric Acute Respiratory Distress Syndrome in COVID-19 Pandemic: Is it the Puzzle of the Century? Indian J Crit Care Med 2022;26(3):264-265.

Expert consensus statements for the management of COVID-19-related acute respiratory failure using a Delphi method.

BACKGROUND: Coronavirus disease 2019 (COVID-19) pandemic has caused unprecedented pressure on healthcare system globally. Lack of high-quality evidence on the respiratory management of COVID-19-related acute respiratory failure (C-ARF) has resulted in wide variation in clinical practice. METHODS: Using a Delphi process, an international panel of 39 experts developed clinical practice statements on the respiratory management of C-ARF in areas where evidence is absent or limited. Agreement was defined as achieved when > 70% experts voted for a given option on the Likert scale statement or > 80% voted for a particular option in multiple-choice questions. Stability was assessed between the two concluding rounds for each statement, using the non-parametric Chi-square (χ2) test (p < 0·05 was considered as unstable). RESULTS: Agreement was achieved for 27 (73%) management strategies which were then used to develop expert clinical practice statements. Experts agreed that COVID-19-related acute respiratory distress syndrome (ARDS) is clinically similar to other forms of ARDS. The Delphi process yielded strong suggestions for use of systemic corticosteroids for critical COVID-19; awake self-proning to improve oxygenation and high flow nasal oxygen to potentially reduce tracheal intubation; non-invasive ventilation for patients with mixed hypoxemic-hypercapnic respiratory failure; tracheal intubation for poor mentation, hemodynamic instability or severe hypoxemia; closed suction systems; lung protective ventilation; prone ventilation (for 16-24 h per day) to improve oxygenation; neuromuscular blocking agents for patient-ventilator dyssynchrony; avoiding delay in extubation for the risk of reintubation; and similar timing of tracheostomy as in non-COVID-19 patients. There was no agreement on positive end expiratory pressure titration or the choice of personal protective equipment. CONCLUSION: Using a Delphi method, an agreement among experts was reached for 27 statements from which 20 expert clinical practice statements were derived on the respiratory management of C-ARF, addressing important decisions for patient management in areas where evidence is either absent or limited. TRIAL REGISTRATION: The study was registered with Clinical trials.gov Identifier: NCT04534569.

Misfortune and spy story in the neurological manifestations of Covid-19.

Covid-19 is associated with different neurological manifestations. About one third of Covid-19 patients have some neurological disorders as paresthesia, headache, cold extremities and disturbances of consciousness, which are more evident in severely affected patients. These neurological manifestations may coexist or precede the onset of respiratory manifestations by about 2-3 weeks. Acute ischaemic stroke (AIS) and associated brain damage may develop due to acute respiratory distress syndrome (ARDS) induced-hypoxia. Prolonged hypoxia in late-stage Covid-19 leads to vasodilatation, intracranial hypertension, brain oedema, and AIS. In view of substantial evidence, this perspective explores the potentially direct or indirect effect of SARS-CoV-2 on the Central Nervous System of patients with COVID-19 pneumonia. The AIS is the end of most Covid-19-induced neurological complications. Covid-19 can lead to various neurological manifestations due to involvement of CNS directly through olfactory neurons or indirectly through induction of cytokine storm.

Arterial Blood Gas as a Predictor of Mortality in COVID Pneumonia Patients Initiated on Noninvasive Mechanical Ventilation: A Retrospective Analysis.

Background: The alveolar-arterial oxygen (A-a) gradient measures the difference between the oxygen concentration in alveoli and the arterial system, which has considerable clinical utility. Materials and methods: It was a retrospective, observational cohort study involving the analysis of patients diagnosed with acute COVID pneumonia and required noninvasive mechanical ventilation (NIV) over a period of 3 months. The primary objective was to investigate the utility of the A-a gradient (pre-NIV) as a predictor of 28-day mortality in COVID pneumonia. The secondary objective included the utility of other arterial blood gas (ABG) parameters (pre-NIV) as a predictor of 28-day mortality. The outcome was also compared between survivors and nonsurvivors. The outcome variables were analyzed by receiver-operating characteristic (ROC) curve, Youden index, and regression analysis. Results: The optimal criterion for A-a gradient to predict 28-day mortality was calculated as ≤430.43 at a Youden index of 0.5029, with the highest area under the curve (AUC) of 0.755 (p <0.0001). On regression analysis, the odds ratio for the A-a gradient was 0.99. A significant difference was observed in ABG predictors, including PaO2, PaCO2, A-a gradient, AO2, and arterial-alveolar (a-A) (%) among nonsurvivors vs survivors (p-value <0.001). The vasopressor requirement, need for renal replacement therapy, total parenteral requirement, and blood transfusion were higher among nonsurvivors; however, a significant difference was achieved with the vasopressor need (p <0.001). Conclusion: This study demonstrated that the A-a gradient is a significant predictor of mortality in patients initiated on NIV for worsening respiratory distress in COVID pneumonia. All other ABG parameters also showed a significant AUC for predicting 28-day mortality, although with variable sensitivity and specificity. Key messages: COVID-19 pneumonia shows an initial presentation with type 1 respiratory failure with increased A-a gradient, while a subsequent impending type 2 respiratory failure requires invasive ventilation. A significant difference was observed in ABG predictors, including PaO2, PaCO2, A-a gradient, AO2, and a-A (%) among nonsurvivors vs survivors. (p-value <0.001). The vasopressor requirement, need for renal replacement therapy, total parenteral requirement, and blood transfusion need were higher among nonsurvivors than survivors; however, a significant difference was achieved with the vasopressor need (p <0.001). How to cite this article: Gupta B, Jain G, Chandrakar S, Gupta N, Agarwal A. Arterial Blood Gas as a Predictor of Mortality in COVID Pneumonia Patients Initiated on Noninvasive Mechanical Ventilation: A Retrospective Analysis. Indian J Crit Care Med 2021;25(8):866-871.

Extracorporeal Membrane Oxygenation in COVID-19 Patients: More Hype than Substance?

Trikha A, Venkateswaran V, Soni KD. Extracorporeal Membrane Oxygenation in COVID-19 Patients: More Hype than Substance? Indian J Crit Care Med 2021;25(11):1322-1323.

COVID-19: Management.

Coronavirus disease (COVID-19) has grasped the world including Pakistan. Clinical features of this disease are variable, ranging from asymptomatic to critical disease. In this unprecedented global war, the Pakistan Chest Society has written a guideline for quick review for the specialists providing care to suspected or confirmed patients. This review highlights the approach to a patient with COVID-19, including definition of the various syndromes of the disease, the abnormal laboratory parameters and outlines the therapeutic measures which are currently under investigation.

Role of H2 receptor blocker famotidine over the clinical recovery of COVID-19 patients: A randomized controlled trial.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global pandemic putting the population at a high risk of infection-related health hazards, mortality and a potential failure of proper medical therapies. Therefore, it is necessary to evaluate the potential use of the existing drugs that could be used as options for the medical management of COVID-19 patients. AIM: To evaluate the role of the H2 receptor blocker "famotidine" in COVID-19 illness. METHODS: This study was done on seriously ill COVID-19 patients admitted to the intensive care unit (ICU) from different institutes in Bangladesh. Patients were divided into famotidine treatment group "A" (famotidine 40 mg to 60 mg oral formulation every 8 h with other treatment as given), and control group "B" (treatment as given). National early warning score (NEWS)-2, and sequential organ failure assessment day-1 score was calculated to evaluate the outcome. Outcomes were evaluated by the time required for clinical improvement, characterized as duration required from enrollment to the achievement of NEWS-2 of ≤ 2 maintained for 24 h; time to symptomatic recovery, defined as the duration in days (from randomization) required for the recovery of the COVID-19 symptoms; mortality rate; duration of ICU and hospital stay; total period of hospitalization; the rate of supplementary oxygen requirement; the computed tomography (CT) chest recovery (%), the time required for the viral clearance and "NEWS-2" on discharge. RESULTS: A total of 208 patients were enrolled in this study with 104 patients in each group. The famotidine treatment group had comparatively better recovery of 75% and a low mortality of 25% than the control with a recovery of 70% and a mortality of 30%. Duration of clinical improvement (group A 9.53 d, group B 14.21 d); hospitalization period among the recovered patients (group A 13.04 d, group B 16.31 d), pulmonary improvement in chest CT (group A 21.7%, group B 13.2%), and the time for viral clearance (group A 20.7 d, group B 23.8 d) were found to be statistically significant P ≤ 0.05. However, the Kaplan Meier survival test was not significant among the two study groups, P = 0.989. CONCLUSION: According to our study, treatment with famotidine achieved a better clinical outcome compared to the control group in severe COVID-19 illness, although no significant survival benefit was found.