Early versus late tracheal intubation in COVID-19 patients: a "pros/cons" debate also considering heart-lung interactions

Diagnosis and Management of Acute Respiratory Failure

Acute hypoxemic respiratory failure is defined by Pao2 less than 60 mm Hg or SaO2 less than 88% and may result from V/Q mismatch, shunt, hypoventilation, diffusion limitation, or low inspired oxygen tension. Acute hypercapnic respiratory failure is defined by Paco2 ≥ 45 mm Hg and pH less than 7.35 and may result from alveolar hypoventilation, increased fraction of dead space, or increased production of carbon dioxide. Early diagnostic maneuvers, such as measurement of SpO2 and arterial blood gas, can differentiate the type of respiratory failure and guide next steps in evaluation and management.

Intubation Time, Lung Mechanics and Outcome in COVID-19 Patients Suffering Acute Respiratory Distress Syndrome: A Single-Center Study

Background

We examined the effect of intubation time and the lung mechanics on clinical outcomes in coronavirus disease 2019 (COVID-19) patients.

Methods

Based on the patient's hospital admission, intubation time was defined as early (≤ 2 days) or late (> 2 days). Patients were further divided into three groups; early (≤ 3 days), late (4 - 6 days), and very late (> 6 days) intubated.

Results

A total of 194 patients were included; 66.5% male, median age 65 years. Fifty-eight patients (29.9%) were intubated early and 136 (70.1%) late. Early intubated patients revealed lower mortality (44.8% vs. 72%, P < 0.001), were younger (60 vs. 67, P = 0.002), had lower sequential organ failure assessment (SOFA) scores (6 vs. 8, P = 0.002) and higher lung compliance on admission days 1, 6 and 12 (42 vs. 36, P = 0.006; 40 vs. 33, P < 0.001; and 37.5 vs. 32, P < 0.001, respectively). Older age (adjusted odds ratio (aOR) = 1.15, P < 0.001), intubation time (aOR = 1.15, P = 0.004), high SOFA scores (aOR = 1.81, P < 0.001), low partial pressure of oxygen (PaO2)/fractional inspired oxygen tension (FiO2) ratio (aOR = 0.96, P = 0.001), and low lung compliance on admission days 1 and 12 (aOR = 1.12, P = 0.012 and aOR = 1.14, P < 0.001, respectively) were associated with higher mortality. Very late and late intubated patients had higher mortality rates than patients intubated early (78.4% vs. 63.4% vs. 44.6%, respectively, P < 0.001).

Conclusions

Among COVID-19 intubated patients, age, late intubation, high SOFA scores, low PaO2/FiO2 ratio, and low lung compliance are associated with higher intensive care unit (ICU) mortality.

Feasibility, safety and efficacy of COVID-19 severe acute respiratory distress syndrome management without invasive mechanical ventilation

BACKGROUND

COVID-19 acute respiratory distress syndrome (ARDS) is often managed with mechanical ventilation (MV), requiring sedation and paralysis, with associated risk of complications. There is limited evidence on the use of high flow nasal cannula (HFNC). We hypothesized that management of COVID-19 ARDS without MV is feasible.

METHODS

Included were all adult patients diagnosed with COVID-19 ARDS, with PaO2/FiO2 ratio <100 at admission, and whose management was initially performed without MV. We evaluated need for intubation during ICU stay, mortality and hospital/ICU length of stay (LOS).

RESULTS

Out of 118 patients, 41 were managed only with HFNC from hospital admission (and at least during first 24 hours in ICU) and had a PaO2/FiO2 ratio <100 (72.9±13.0). Twenty-nine out of 41 patients never required MV: 24 of them survived and were discharged home. Their median ICU LOS was 11 (7-17) days, and their hospital LOS was 29 (18-45) days. We identified PaO2/FiO2 ratio at ICU admission as the only significant predictor for need for MV during ICU stay. We also identified age, length of non-invasive respiratory support before ICU admission, mean value of PaO2/FiO2 ratio during first half and whole ICU stay as predictors of mortality.

CONCLUSIONS

It is safe to monitor in ICU and use HFNC in patients affected by COVID-19 ARDS who initially present data suggesting an early need for intubation. The 41 patients admitted with a PaO2/FiO2 ratio <100 and initially treated only with HFNC show a 22% mortality that is in the lower range of what is reported in recent literature.

Beneficial effects of prehospital use of statins in a large United States cohort of hospitalized coronavirus disease 2019 patients

AIMS

This large cohort study aimed to assess the role of chronic statin use on COVID-19 disease severity.

METHODS

An observational retrospective study from electronic medical records of hospitalized patients (n = 43 950) with COVID-19 between January and September 2020 in 185 hospitals in the United States. A total of 38 875 patients met inclusion criteria; 23 066 were included in the propensity-matched sampling with replacement cohort; 11 533 were prehospital statin users. The primary outcome was all-cause death; secondary outcomes were death from COVID-19 and serious complications. Mean, standard deviation, chi-square test, Student's t-test, linear regression, and binary and multinomial logistic regressions were used for statistical analysis.

RESULTS

Among 38 875 patients, 30% were chronic statin users [mean age, 70.82 (±12.25); 47.1% women] and 70% were statin nonusers [mean age, 58.44 (±18.27); 48.5% women]. Key propensity-matched outcomes among 11 533 chronic statin users showed 20% lower risk of all-cause mortality (OR 0.80, 95% CI 0.74-0.86, P < 0.001), 23% lower risk of mortality from COVID-19 (OR 0.77, 95% CI 0.71-0.84, P < 0.001), 16% lower risk of ICU admission (OR 0.84, 95% CI 0.79-0.89, P < 0.001), 24% lower risk of critical acute respiratory distress syndrome with COVID-19 (OR 0.76, 95% CI 0.70-0.83, P < 0.001), 23% lower risk of mechanical ventilation (OR 0.77, 95% CI 0.71-0.82, P < 0.001), 20% lower risk of severe sepsis with septic shock (OR 0.80, 95% CI 0.67-0.93, P = 0.004), shorter hospital length of stay [9.87 (±8.94), P < 0.001] and brief duration of mechanical ventilation [8.90 (±8.94), P < 0.001].

CONCLUSION

Chronic use of statins is associated with reduced mortality and improved clinical outcomes in patients hospitalized for COVID-19.

Association between Body Mass Index and Hospital Outcomes for COVID-19 Patients: A Nationwide Study

BACKGROUND

Coronavirus disease 2019 (COVID-19) caused significant morbidity and mortality worldwide. There is limited information describing the hospital outcomes of COVID-19 patients in regard to specific body mass index (BMI) categories.

METHODS

We utilized the Healthcare Cost and Utilization Project Nationwide Inpatient Sample (NIS) 2020 database to collect information on patients hospitalized for COVID-19 in the United States. Using the International Classification of Diseases, 10th revision, Clinical Modification (ICD-10-CM) coding system, adult patients (≥18 years of age) with a primary hospitalization for COVID-19 were identified. Adjusted analyses were performed to assess for mortality, morbidity, and resource utilization, and compare the outcomes among patients categorized according to BMI.

RESULTS

A total of 305,284 patients were included in this study. Of them, 248,490 had underlying obesity, defined as BMI ≥ 30. The oldest patients were observed to have BMI < 19, while youngest patients were in the BMI > 50 category. BMI < 19 category had the highest crude in-hospital mortality rate. However, after adjusted regression, patients with BMI > 50 (adjusted odds ratio (aOR) 1.63, 95% CI 1.48-1.79, p-value < 0.001) had the highest increased odds, at 63%, of in-hospital mortality compared to all other patients in the study. Patients with BMI > 50 also had the highest increased odds of needing invasive mechanical ventilation (IMV) and mortality associated with IMV compared to all other patient, by 37% and 61%, respectively. Obese patients were noted to have shorter average hospital length of stay (LOS), by 1.07 days, compared to non-obese patients, but there was no significant difference in average hospitalization charges.

CONCLUSION

Among obese patients primarily hospitalized with COVID-19, those with BMI ≥ 40 had significantly increased rates of all-cause in-hospital mortality, need for IMV, mortality associated with IMV, and septic shock. Overall, obese patients had shorter average hospital LOS, however, did not have significantly higher hospitalization charges.

Validation of Sequential ROX-Index Score Beyond 12 Hours in Predicting Treatment Failure and Mortality in COVID-19 Patients Receiving Oxygen via High-Flow Nasal Cannula

Background

High-flow nasal cannula (HFNC) is an oxygen delivery method shown to reduce the risk of intubation and mortality in patients with type 1 respiratory failure. The ROX-index score can predict HFNC failure. This study aims to evaluate sequential ROX-index assessments as predictors of HFNC failure and mortality.

Methods

Prospective observational single-center study including all adult patients with positive SARS-CoV-2 PCR placed under HFNC from 1st November 2020 to 31st May 2021, and patients with hemodynamic instability or unable to tolerate HFNC were excluded. The primary endpoint was successful HFNC de-escalation.

Results

In univariate analysis, HFNC de-escalation was associated with younger age (59.2 ± 14 vs. 67.7 ± 10.5 and p < 0.001), lower levels of serum lactate (1.1 vs. 1.5 and p=0.013), and higher ROX-index at 12 hrs (5.09 vs. 4.13 and p < 0.001). ROC curve analysis of ROX-index at 12 hrs yielded a c-statistic of 71.2% (95% CI 61.6-80.9 and p < 0.001). ROX-index at 12 hrs and age retained significance in multivariate analysis. Using an optimal cutoff point of 4.43, we calculated a sensitivity of 64.5% and specificity of 69.6%. In univariate survival analysis, older age (68.8 ± 9.7 vs. 58.9 ± 13.9 and p < 0.001), greater creatinine values (0.96 vs. 0.84 and p=0.022), greater SOFA score (p=0.039), and a lower 12 hrs ROX-index (4.22 vs. 4.95 and p=0.02) were associated with hospital mortality. The SOFA score and age retained significance in multivariate survival analysis.

Conclusion

ROX-index is proven to be a valuable and easy-to-use tool for clinicians in the assessment of COVID-19 patients under HFNC.

Providing respiratory and ventilation care in the face of shifting evidence: current opinion in critical care

PURPOSE OF REVIEW

To review the clinical problem and noninvasive treatments of hypoxemia in critically-ill patients with coronavirus disease 2019 pneumonia and describe recent advances in evidence supporting bedside decision making.

RECENT FINDINGS

High-flow nasal oxygen and noninvasive ventilation, along with awake prone positioning are potentially helpful therapies for acute hypoxemic respiratory failure. High-flow nasal oxygen therapy has been widely implemented as a form of oxygen support supported by prepandemic randomized controlled trials showing possible benefit over noninvasive ventilation. Given the sheer volume of patients, noninvasive ventilation was often required, and based on a well conducted randomized controlled trial there was a developing role for helmet-interface noninvasive. Coupled with noninvasive supports, the use of awake prone positioning demonstrated physiological benefits, but randomized controlled trial data did not demonstrate clear outcome superiority.

SUMMARY

The use of noninvasive oxygen strategies and our understanding of the proposed mechanisms are evolving. Variability in patient severity and physiology may dictate a personalized approach to care. High-flow nasal oxygen may be paired with awake and spontaneously breathing prone-positioning to optimize oxygen and lung mechanics but requires further insight before widely applying to clinical practice.

Early intubation and clinical outcomes in patients with severe COVID-19: a systematic review and meta-analysis

BACKGROUND

Evidence regarding the timing of the application of mechanical ventilation among patients with severe coronavirus disease (COVID-19) is insufficient. This systematic review and meta-analysis aimed to evaluate the effectiveness of early intubation compared to late intubation in patients with severe and critical COVID-19.

METHODS

For this study, we searched the MEDLINE, EMBASE, and Cochrane databases as well as one Korean domestic database on July 15, 2021. We updated the search monthly from September 10, 2021 to February 10, 2022. Studies that compared early intubation with late intubation in patients with severe COVID-19 were eligible for inclusion. Relative risk (RR) and mean difference (MD) were calculated as measures of effect using the random-effects model for the pooled estimates of in-hospital mortality, intensive care unit (ICU) length of stay (LOS), duration of mechanical ventilation (MV), hospital LOS, ICU-free days, and ventilator-free days. Subgroup analysis was performed based on the definition of early intubation and the index time. To assess the risk of bias in the included studies, we used the Risk of Bias Assessment tool for Non-randomized studies 2.0.

RESULTS

Of the 1523 records identified, 12 cohort studies, involving 2843 patients with severe COVID-19 were eligible. There were no differences in in-hospital mortality (8 studies, n = 795; RR 0.91, 95% CI 0.75-1.10, P = 0.32, I² = 33%), LOS in the ICU (9 studies, n = 978; MD -1.77 days, 95% CI -4.61 to 1.07 days, P = 0.22, I² = 78%), MV duration (9 studies, n = 1,066; MD -0.03 day, 95% CI -1.79 to 1.72 days, P = 0.97, I² = 49%), ICU-free days (1 study, n = 32; 0 day vs. 0 day; P = 0.39), and ventilator-free days (4 studies, n = 344; MD 0.94 day, 95% CI -4.56 to 6.43 days, P = 0.74, I² = 54%) between the early and late intubation groups. However, the early intubation group had significant advantage in terms of hospital LOS (6 studies, n = 738; MD -4.32 days, 95% CI -7.20 to -1.44 days, P = 0.003, I² = 45%).

CONCLUSION

This study showed no significant difference in both primary and secondary outcomes between the early intubation and late intubation groups. Trial registration This study was registered in the Prospective Register of Systematic Reviews on 16 February, 2022 (registration number CRD42022311122).

Outcomes of COVID-19 Patients with Severe Hypoxemic Acute Respiratory Failure: Non-Invasive Ventilation vs. Straight Intubation-A Propensity Score-Matched Multicenter Cohort Study

The best timing for endotracheal intubation in patients with coronavirus disease 2019 (COVID-19) hypoxemic acute respiratory failure (hARF) remains debated. Aim of this study is to compare the outcomes of COVID-19 patients with hARF receiving either a trial of non-invasive ventilation (NIV) or intubated with no prior attempt of NIV ("straight intubation"). All consecutive patients admitted to the 25 participating ICUs were included and divided in two groups: the "straight intubation" group and the "NIV" group. A propensity score matching was performed to correct for biases associated with the choice of the respiratory support. Primary outcome was in-hospital mortality. Secondary outcomes were length of mechanical ventilation, hospital stay and reintubation rate. A total of 704 COVID-19 patients were admitted to ICUs during the study period. After matching, 141 patients were included in each group. No clinically relevant difference at ICU admission was found between groups. In-hospital mortality was significantly lower in the NIV group (22.0% vs. 36.2%), with no significant difference in secondary endpoints. There was no significant mortality difference between patients who received straight intubation and those intubated after NIV failure. In COVID-19 patients with hARF it is worth and safe attempting a trial of NIV prior to intubation.

Airway Management of Patients with Suspected or Confirmed COVID-19: Survey Results from Physicians from 19 Countries in Latin America

Airway management during the COVID-19 pandemic has been one of the most challenging aspects of care that anesthesiologists and intensivists face. This study was conducted to evaluate the management of tracheal intubation in patients with suspected or confirmed COVID-19 infection. This is a cross-sectional and international multicenter study based on a 37-item questionnaire. The survey was available to physicians who had performed intubations and tracheostomies in patients with suspected or confirmed COVID-19 and had provided informed consent to participate. The primary outcome is the preference to use a specific device for tracheal intubation. Secondary outcomes are clinical practice variables, use of video laryngoscopes, difficult airway management, and safety features to prevent cross-infection. This study included 2411 physicians who performed an average of 11.90 and 20.67 tracheal intubations in patients diagnosed or suspected of having COVID-19 disease, respectively. Physicians were mainly from the specialties of Anesthesiology (61.2%) and Intensive Care (7.4%). COVID-19 infection diagnosed by positive PCR or serology in physicians participating in intubation in this study was 15.1%. Respondents considered preoxygenation for more than three minutes very useful (75.7%). The preferred device for tracheal intubation was the video laryngoscope (64.8%). However, the direct laryngoscope (57.9%) was the most commonly used, followed by the video laryngoscope (37.5%). The preferred device to facilitate intubation was the Eschmann guide (34.2%). Percutaneous tracheostomy was the preferred technique (39.5%) over the open tracheostomy (22%). The predicted or unpredicted difficult airway management in these patients was preferably performed with a video laryngoscope (61.7% or 63.7, respectively). Intubation was mostly performed by two or more expert airway physicians (61.6%). The use of personal protective equipment increased the practitioners' discomfort during intubation maneuvers. The video laryngoscope is the preferred device for intubating patients with COVID-19, combined with the Eschmann guide, flexible stylet within the endotracheal tube, or Frova guide to facilitate intubation. The sub-analysis of the two groups of physicians by the level of intubation experience showed a higher use of the video laryngoscope (63.4%) in the experts group and no significant differences between the two groups in terms of cross-infection rates in physicians, in their preference for the use of the video laryngoscope or in the number of intubations performed in confirmed or suspected COVID-19 patients.

SIMEU position paper on non-invasive respiratory support in COVID-19 pneumonia

The rapid worldwide spread of the Coronavirus disease (COVID-19) crisis has put health systems under pressure to a level never experienced before, putting intensive care units in a position to fail to meet an exponentially growing demand. The main clinical feature of the disease is a progressive arterial hypoxemia which rapidly leads to ARDS which makes the use of intensive care and mechanical ventilation almost inevitable. The difficulty of health systems to guarantee a corresponding supply of resources in intensive care, together with the uncertain results reported in the literature with respect to patients who undergo early conventional ventilation, make the search for alternative methods of oxygenation and ventilation and potentially preventive of the need for tracheal intubation, such as non-invasive respiratory support techniques particularly valuable. In this context, the Emergency Department, located between the area outside the hospital and hospital ward and ICU, assumes the role of a crucial junction, due to the possibility of applying these techniques at a sufficiently early stage and being able to rapidly evaluate their effectiveness. This position paper describes the indications for the use of non-invasive respiratory support techniques in respiratory failure secondary to COVID-19-related pneumonia, formulated by the Non-invasive Ventilation Faculty of the Italian Society of Emergency Medicine (SIMEU) on the base of what is available in the literature and on the authors' direct experience. Rationale, literature, tips & tricks, resources, risks and expected results, and patient interaction will be discussed for each one of the escalating non-invasive respiratory techniques: standard oxygen, HFNCO, CPAP, NIPPV, and awake self-repositioning. The final chapter describes our suggested approach to the failing patient.

Various Aspects of Non-Invasive Ventilation in COVID-19 Patients: A Narrative Review

Non-invasive ventilation (NIV) is primarily used to treat acute respiratory failure. However, it has broad applications to manage a range of other diseases successfully. The main advantage of NIV lies in its capability to provide the same physiological effects as invasive ventilation while avoiding the placement of an artificial airway and its associated life-threatening complications. The war on the COVID-19 pandemic is far from over. The present narrative review aimed at identifying various aspects of NIV usage, in COVID-19 and other patients, such as the onset time, mode, setting, positioning, sedation, and types of interface. A search for articles published from May 2020 to April 2021 was conducted using MEDLINE, PMC central, Scopus, Web of Science, Cochrane Library, and Embase databases. Of the initially identified 5,450 articles, 73 studies and 24 guidelines on the use of NIV were included. The search was limited to studies involving human cases and English language articles. Despite several reported benefits of NIV, the evidence on the use of NIV in COVID-19 patients does not yet fully support its routine use.

Predictors of Pneumothorax/Pneumomediastinum in Mechanically Ventilated COVID-19 Patients

OBJECTIVE

To determine the incidence, predictors, and outcome of pneumothorax (PNX)/pneumomediastinum (PMD) in coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS).

DESIGN

Observational study.

SETTING

Tertiary-care university hospital.

PARTICIPANTS

One hundred sixteen consecutive critically ill, invasively ventilated patients with COVID-19 ARDS.

INTERVENTIONS

The authors collected demographic, mechanical ventilation, imaging, laboratory, and outcome data. Primary outcome was the incidence of PNX/PMD. Multiple logistic regression analyses were performed to identify predictors of PNX/PMD.

MEASUREMENTS AND MAIN RESULTS

PNX/PMD occurred in a total of 28 patients (24.1%), with 22 patients developing PNX (19.0%) and 13 developing PMD (11.2%). Mean time to development of PNX/PMD was 14 ± 11 days from intubation. The authors found no significant difference in mechanical ventilation parameters between patients who developed PNX/PMD and those who did not. Mechanical ventilation parameters were within recommended limits for protective ventilation in both groups. Ninety-five percent of patients with PNX/PMD had the Macklin effect (linear collections of air contiguous to the bronchovascular sheaths) on a baseline computed tomography scan, and tended to have a higher lung involvement at intensive care unit (ICU) admission (Radiographic Assessment of Lung Edema score 32.2 ± 13.4 v 18.7 ± 9.8 in patients without PNX/PMD, p = 0.08). Time from symptom onset to intubation and time from total bilirubin on day two after ICU admission were the only independent predictors of PNX/PMD. Mortality was 60.7% in patients who developed PNX/PMD versus 38.6% in those who did not (p = 0.04).

CONCLUSION

PNX/PMD occurs frequently in COVID-19 patients with ARDS requiring mechanical ventilation, and is associated with increased mortality. Development of PNX/PMD seems to occur despite use of protective mechanical ventilation and has a radiologic predictor sign.

Semiquantitative ChestCT Severity Score Predicts Failure of Noninvasive Positive-Pressure Ventilation in Patients Hospitalized for COVID-19 Pneumonia

Objective

Noninvasive positive-pressure ventilation (NPPV) emerged as an efficient tool for treatment of COVID-19 pneumonia. The factors influencing NPPV failure still are elusive. The aim of the study was to investigate the relationships between semiquantitative chest computed tomography (CT) scoring and NPPV failure and mortality in patients with COVID-19.

Design

Observational study.

Setting

Nonintensive care setting.

Participants

A total of 112 patients consecutively admitted for COVID-19 pneumonia.

Interventions

Usual care including various degrees of respiratory support.

Measurements and Main Results

The semiquantitative CT score was calculated at hospital admission. Subgroups were identified according to the ventilation strategy used (oxygen delivered by Venturi mask n = 53; NPPV-responder n = 38; NPPV-failure n = 21). The study's primary endpoint was the use of NPPV. The secondary endpoints were NPPV failure and in-hospital death, respectively. CT score progressively increased among groups (six v nine v 14, p < 0.05 among all). CT score was an independent predictor of all study endpoints (primary endpoint: 1.25 [95% confidence interval {CI} 1.1-1.4], p = 0.001; NPPV failure: 1.41 [95% CI 1.18-1.69], p < 0.001; in-hospital mortality: 1.21 [95% CI 1.07-1.38], p = 0.003). According to receiver operator characteristics curve analysis, CT score was the most accurate variable for prediction of NPPV failure (area under the curve 0.862 with p < 0.001; p < 0.05 v other variables).

Conclusions

The authors reported the common and effective use of NPPV in patients with COVID-19 pneumonia. In the authors’ population, a semiquantitative chest CT analysis at hospital admission accurately identified those patients responding poorly to NPPV.