Critical Care Bulletin - January 2022

 

Mechanical power in pediatric acute respiratory distress syndrome: a PARDIE study

 

by Anoopindar K. Bhalla, Margaret J. Klein, Vicent Modesto I Alapont, Guillaume Emeriaud, Martin C. J. Kneyber, Alberto Medina, Pablo Cruces, Franco Diaz, Muneyuki Takeuchi, Aline B. Maddux, Peter M. Mourani, Cristina Camilo, Benjamin R. White, Nadir Yehya, John Pappachan, Matteo Di Nardo

Critical Care volume 26, Article number: 2 (2022) Published: 03 January 2022

Background

Mechanical power is a composite variable for energy transmitted to the respiratory system over time that may better capture risk for ventilator-induced lung injury than individual ventilator management components. We sought to evaluate if mechanical ventilation management with a high mechanical power is associated with fewer ventilator-free days (VFD) in children with pediatric acute respiratory distress syndrome (PARDS).

Methods

Retrospective analysis of a prospective observational international cohort study.

Results

There were 306 children from 55 pediatric intensive care units included. High mechanical power was associated with younger age, higher oxygenation index, a comorbid condition of bronchopulmonary dysplasia, higher tidal volume, higher delta pressure (peak inspiratory pressure—positive end-expiratory pressure), and higher respiratory rate. Higher mechanical power was associated with fewer 28-day VFD after controlling for confounding variables (per 0.1 J·min−1·Kg−1 Subdistribution Hazard Ratio (SHR) 0.93 (0.87, 0.98), p = 0.013). Higher mechanical power was not associated with higher intensive care unit mortality in multivariable analysis in the entire cohort (per 0.1 J·min−1·Kg−1 OR 1.12 [0.94, 1.32], p = 0.20). But was associated with higher mortality when excluding children who died due to neurologic reasons (per 0.1 J·min−1·Kg−1 OR 1.22 [1.01, 1.46], p = 0.036). In subgroup analyses by age, the association between higher mechanical power and fewer 28-day VFD remained only in children < 2-years-old (per 0.1 J·min−1·Kg−1 SHR 0.89 (0.82, 0.96), p = 0.005). Younger children were managed with lower tidal volume, higher delta pressure, higher respiratory rate, lower positive end-expiratory pressure, and higher PCO2 than older children. No individual ventilator management component mediated the effect of mechanical power on 28-day VFD.

Conclusions

Higher mechanical power is associated with fewer 28-day VFDs in children with PARDS. This association is strongest in children < 2-years-old in whom there are notable differences in mechanical ventilation management. While further validation is needed, these data highlight that ventilator management is associated with outcome in children with PARDS, and there may be subgroups of children with higher potential benefit from strategies to improve lung-protective ventilation.

Take Home Message: Higher mechanical power is associated with fewer 28-day ventilator-free days in children with pediatric acute respiratory distress syndrome. This association is strongest in children <2-years-old in whom there are notable differences in mechanical ventilation management.

 

Pulse oximetry, racial bias and statistical bias

 

by Martin J. Tobin and Amal Jubran 

 

Annals of Intensive Care volume 12, Article number: 2 (2022) Published: 04 January 2022

 

On November 21, 2021, the British Health Minister, Sajid Javid, published an article in the Sunday Times pointing out that pulse oximeters tend to be inaccurate in patients with dark skin pigmentation [1]. The Minister remarked that “technologies are created and developed by people, and so bias, however inadvertent, can be an issue here too.” The article attracted immediate and widespread attention, being covered by newspapers and television channels around the world. Mr. Javid expanded on his concerns during interviews with Andrew Maar on the BBC and Trevor Phillips on Sky News.

A few years after the introduction of pulse oximetry in the 1980s, we noticed that oximeters were less reliable in Black patients. In a 1990 article focusing on oxygenation in mechanically ventilated patients, we reported that pulse oximetry was almost 2½ times less accurate in Black patients [2].

Given that pulse oximetry operates by shining a light through the skin at two wavelengths—660 nm (red) and 940 nm (infrared)—and measuring the difference in light absorbance at the two wavelengths to estimate arterial oxygen saturation [3], we surmised that inaccuracy in Black patients is related to skin pigmentation. Supporting evidence is the increase in the difference in light absorbance between red and infrared wavelengths with use of black nail varnish, causing pulse oximeters to register falsely low saturations [4].

Estimates of oxygen saturation by pulse oximetry differ from true oxygen saturation in an arterial blood sample (the reference standard). The magnitude of the difference between non-invasive estimates and reference-standard measurements (in a group of patients) is quantified as mean and standard deviation, which statisticians dub “bias and precision.” In White patients, the mean and standard deviation of the difference between non-invasive estimates of oxygen saturation and the reference standard are each around 2%, whereas they both exceed 3% in Black patients [2]. In our study, a pulse oximeter target of 92% ensured a safe arterial oxygen tension (PaO2) greater than 60 mmHg in 91.7% of White patients, but in only 50% of our Black patients [2].

In the first rigorous description of happy hypoxia in COVID-19, a situation where patients experience life-threateningly low oxygen saturations without provoking dyspnoea, we discussed several contributors to the phenomenon including the greater unreliability of pulse oximetry in Black patients [5]. Managing patients with unreliable measurements of oxygenation is hazardous, partly because dangerously low saturations are missed, but also because low saturations are exaggerated and lead to unnecessary intubation [6]. A major contributor to patient mortality in COVID-19 is inappropriate intubation [7], and it is possible that unreliable measurements of the oxygen saturations have contributed to increased mortality reported in Black patients [8].

In our 1990 article, we deduced that pulse oximetry was less reliable in Black patients because calibration data were drawn largely from White subjects [2]. The algorithms employed within software of pulse oximeters are trade secrets and not open to scrutiny [3]. We recommended that manufacturers collect data in Black patients to develop better calibration algorithms. In the 31 years since we made this recommendation, we are not aware of any manufacturer attempting to incorporate adjusted algorithms into pulse oximeters. The inaccuracy of pulse oximetry in Black patients is one further example of how medical information generated in (and for) White people contributes to inferior clinical outcome in patients of colour [9].

Hopefully, the attention generated by Mr. Javid’s highlighting of a significant problem with pulse oximetry will rouse manufacturers into action. Mr. Javid is working with his US counterpart, Xavier Becerra, to introduce new international medical standards. In the meantime, it would help if authors reverted to the more mundane (and precise) terminology of mean and standard deviation and refrained from use of the dodgy terms “bias and precision”, which gives rise to the notion that inanimate objects are capable of racial prejudice.

 

 

Sepsis Definitions: I Know It When I See It*

 

by Parker, Margaret M. 

 

Critical Care Medicine: January 2022 - Volume 50 - Issue 1 - p 148-150

 

Justice Potter Stewart’s comment regarding pornography that while he “wouldn’t attempt further to define it…I know it when I see it” could just as readily be said in reference to sepsis. Over the past 3–4 decades, efforts have been made to define sepsis, severe sepsis, and septic shock more objectively. For purposes of this editorial, “sepsis” will include the full spectrum of sepsis, severe sepsis, and septic shock. Why is sepsis so difficult to define? There are many signs, symptoms, and laboratory abnormalities that commonly occur in patients with sepsis, but there is not a single “gold standard” definition or criterion that clinicians can all agree on and that facilitates the prompt recognition of the syndrome. The manifestations of sepsis are highly variable, and an infecting organism is not identified in over a third of the patients (1). In children, the diagnosis is further complicated by age- and size-dependent developmental changes. Why is it important to have objective criteria with which to define sepsis? The principal reason is that the prompt recognition and treatment of sepsis have been shown to improve survival (2,3). In comparison with patients in the Emergency Department, recognition of sepsis in hospital inpatients is frequently delayed with a consequent delay in antibiotic therapy and increase in mortality (4,5). An additional and possibly equally important reason to have objective criteria to define sepsis is to enable research studies to be carried out on appropriate populations, which will enhance valid comparison of clinical trials that focus on comparable patient populations…

 

Patterns of ICU admissions and outcomes in patients with solid malignancies over the revolution of cancer treatment

by Clara Vigneron, Julien Charpentier, Sandrine Valade, Jérôme Alexandre, Samy Chelabi, Lola-Jade Palmieri, Nathalie Franck, Valérie Laurence, Jean-Paul Mira, Matthieu Jamme and Frédéric Pène 

Annals of Intensive Care volume 11, Article number: 182 (2021) Published: 24 December 2021

Background

Major therapeutic advances including immunotherapy and targeted therapies have been changing the face of oncology and resulted in improved prognosis as well as in new toxic complications. The aim of this study is to appraise the trends in intensive care unit (ICU) admissions and outcomes of critically ill patients with solid malignancies. We performed a retrospective single-centre study over a 12-year period (2007–2018) including adult patients with solid malignancies requiring unplanned ICU admission. Admission patterns were classified as: (i) specific if directly related to the underlying cancer; (ii) non-specific; (iii) drug-related or procedural adverse events.

Results

1525 patients were analysed. Lung and gastro-intestinal tract accounted for the two main tumour sites. The proportion of patients with metastatic diseases increased from 48.6% in 2007–2008 to 60.2% in 2017–2018 (p = 0.004). Critical conditions were increasingly related to drug- or procedure-related adverse events, from 8.8% of ICU admissions in 2007–2008 to 16% in 2017–2018 (p = 0.01). The crude severity of critical illness at ICU admission did not change over time. The ICU survival rate was 77.4%, without any significant changes over the study period. Among the 1279 patients with complete follow-up, the 1-year survival rate was 33.2%. Independent determinants of ICU mortality were metastatic disease, cancer in progression under treatment, admission for specific complications and the extent of organ failures (invasive and non-invasive ventilation, inotropes/vasopressors, renal replacement therapy and SOFA score). One-year mortality in ICU-survivors was independently associated with lung cancer, metastatic disease, cancer in progression under treatment, admission for specific complications and decision to forgo life-sustaining therapies.

Conclusion

Advances in the management and the prognosis of solid malignancies substantially modified the ICU admission patterns of cancer patients. Despite underlying advanced and often metastatic malignancies, encouraging short-term and long-term outcomes should help changing the dismal perception of critically ill cancer patients.

 

 

 

 

 

 

Racial Disparities in ICU Outcomes: A Systematic Review*

 

by McGowan, Samuel K.; Sarigiannis, Kalli A.; Fox, Samuel C.; Gottlieb, Michael A.; Chen, Elaine 

 

Critical Care Medicine: January 2022 - Volume 50 - Issue 1 - p 1-20

 

Objectives: 

Racial disparities in the United States healthcare system are well described across a variety of clinical settings. The ICU is a clinical environment with a higher acuity and mortality rate, potentially compounding the impact of disparities on patients. We sought to systematically analyze the literature to assess the prevalence of racial disparities in the ICU.

Data Sources: 

We conducted a comprehensive search of PubMed/MEDLINE, Scopus, CINAHL, and the Cochrane Library.

Study Selection: 

We identified articles that evaluated racial differences on outcomes among ICU patients in the United States. Two authors independently screened and selected articles for inclusion.

Data Extraction: 

We dual-extracted study characteristics and outcomes that assessed for disparities in care (e.g., in-hospital mortality, ICU length of stay). Studies were assessed for bias using the Newcastle-Ottawa Scale.

Data Synthesis: 

Of 1,325 articles screened, 25 articles were included (n = 751,796 patients). Studies demonstrated race-based differences in outcomes, including higher mortality rates for Black patients when compared with White patients. However, when controlling for confounding variables, such as severity of illness and hospital type, mortality differences based on race were no longer observed. Additionally, results revealed that Black patients experienced greater financial impacts during an ICU admission, were less likely to receive early tracheostomy, and were less likely to receive timely antibiotics than White patients. Many studies also observed differences in patients’ end-of-life care, including lower rates on the quality of dying, less advanced care planning, and higher intensity of interventions at the end of life for Black patients.

Conclusions: 

This systematic review found significant differences in the care and outcomes among ICU patients of different races. Mortality differences were largely explained by accompanying demographic and patient factors, highlighting the effect of structural inequalities on racial differences in mortality in the ICU. This systematic review provides evidence that structural inequalities in care persist in the ICU, which contribute to racial disparities in care. Future research should evaluate interventions to address inequality in the ICU.

 

Body Mass Index and Mortality in Coronavirus Disease 2019 and Other Diseases: A Cohort Study in 35,506 ICU Patients

 

by Kooistra, Emma J.; Brinkman, Sylvia; van der Voort, Peter H. J.; de Keizer, Nicolette F.; Dongelmans, Dave A.; Kox, Matthijs; Pickkers, Peter 

 

Critical Care Medicine: January 2022 - Volume 50 - Issue 1 - p e1-e10

 

OBJECTIVES: 

Obesity is a risk factor for severe coronavirus disease 2019 and might play a role in its pathophysiology. It is unknown whether body mass index is related to clinical outcome following ICU admission, as observed in various other categories of critically ill patients. We investigated the relationship between body mass index and inhospital mortality in critically ill coronavirus disease 2019 patients and in cohorts of ICU patients with non-severe acute respiratory syndrome coronavirus 2 viral pneumonia, bacterial pneumonia, and multiple trauma.

DESIGN: 

Multicenter observational cohort study.

SETTING: 

Eighty-two Dutch ICUs participating in the Dutch National Intensive Care Evaluation quality registry.

PATIENTS: 

Thirty-five–thousand five-hundred six critically ill patients.

INTERVENTIONS: 

None.

MEASUREMENTS AND MAIN RESULTS: 

Patient characteristics and clinical outcomes were compared between four cohorts (coronavirus disease 2019, nonsevere acute respiratory syndrome coronavirus 2 viral pneumonia, bacterial pneumonia, and multiple trauma patients) and between body mass index categories within cohorts. Adjusted analyses of the relationship between body mass index and inhospital mortality within each cohort were performed using multivariable logistic regression. Coronavirus disease 2019 patients were more likely male, had a higher body mass index, lower Pao2/Fio2 ratio, and were more likely mechanically ventilated during the first 24 hours in the ICU compared with the other cohorts. Coronavirus disease 2019 patients had longer ICU and hospital length of stay, and higher inhospital mortality. Odds ratios for inhospital mortality for patients with body mass index greater than or equal to 35 kg/m2 compared with normal weight in the coronavirus disease 2019, nonsevere acute respiratory syndrome coronavirus 2 viral pneumonia, bacterial pneumonia, and trauma cohorts were 1.15 (0.79–1.67), 0.64 (0.43–0.95), 0.73 (0.61–0.87), and 0.81 (0.57–1.15), respectively.

CONCLUSIONS: 

The obesity paradox, which is the inverse association between body mass index and mortality in critically ill patients, is not present in ICU patients with coronavirus disease 2019–related respiratory failure, in contrast to nonsevere acute respiratory syndrome coronavirus 2 viral and bacterial respiratory infections.

 

Dangers of hyperoxia

 

by Mervyn Singer, Paul J. Young, John G. Laffey, Pierre Asfar, Fabio Silvio Taccone, Markus B. Skrifvars, Christian S. Meyhoff and Peter Radermacher 

 

Critical Care volume 25, Article number: 440 (2021) Published: 19 December 2021

Oxygen (O2) toxicity remains a concern, particularly to the lung. This is mainly related to excessive production of reactive oxygen species (ROS). Supplemental O2, i.e. inspiratory O2 concentrations (FIO2) > 0.21 may cause hyperoxaemia (i.e. arterial (a) PO2 > 100 mmHg) and, subsequently, hyperoxia (increased tissue O2 concentration), thereby enhancing ROS formation. Here, we review the pathophysiology of O2 toxicity and the potential harms of supplemental O2 in various ICU conditions. The current evidence base suggests that PaO2 > 300 mmHg (40 kPa) should be avoided, but it remains uncertain whether there is an “optimal level” which may vary for given clinical conditions. Since even moderately supra-physiological PaO2 may be associated with deleterious side effects, it seems advisable at present to titrate O2 to maintain PaO2 within the normal range, avoiding both hypoxaemia and excess hyperoxaemia.

 

Hyperglycemia and insulin resistance in COVID-19 versus non-COVID critical illness: Are they really different?

 

by Lies Langouche, Greet Van den Berghe and Jan Gunst 

 

Critical Care volume 25, Article number: 437 (2021) Published: 17 December 2021

 

Hyperglycemia frequently develops in patients with severe COVID-19, regardless of preadmission diabetes status, as in non-COVID critically ill patients. In non-COVID patients, stress hyperglycemia has been attributed to insulin resistance due to elevated counterregulatory hormones, cytokines, and drugs including steroids, although beta-cell dysfunction through prolonged hyperglycemia, poor beta-cell reserve, hypoperfusion and inflammation may co-exist in some patients. As in non-COVID patients, numerous observational studies have associated more severe hyperglycemia and increased glucose variability with poor outcome in COVID-19 patients. However, causality remains unclear, since insulin resistance and resultant hyperglycemia closely relate to illness severity. In this regard, a recent observational study also associated insulin treatment with increased mortality of COVID-19. Evidently, observational studies have an inherent risk of residual confounding, whereby the ideal glucose target can only be derived from adequately powered randomized controlled trials (RCTs)…

 

Impact of rewarming rate on interleukin-6 levels in patients with shockable cardiac arrest receiving targeted temperature management at 33 °C: the ISOCRATE pilot randomized controlled trial

by Jean-Baptiste Lascarrou, Elie Guichard, Jean Reignier, Amélie Le Gouge, Caroline Pouplet, Stéphanie Martin, Jean-Claude Lacherade and Gwenhael Colin 

Critical Care volume 25, Article number: 434 (2021) Published: 17 December 2021

Purpose

While targeted temperature management (TTM) has been recommended in patients with shockable cardiac arrest (CA) and suggested in patients with non-shockable rhythms, few data exist regarding the impact of the rewarming rate on systemic inflammation. We compared serum levels of the proinflammatory cytokine interleukin-6 (IL6) measured with two rewarming rates after TTM at 33 °C in patients with shockable out-of-hospital cardiac arrest (OHCA).

Methods

ISOCRATE was a single-center randomized controlled trial comparing rewarming at 0.50 °C/h versus 0.25 °C/h in patients coma after shockable OHCA in 2016–2020. The primary outcome was serum IL6 level 24–48 h after reaching 33 °C. Secondary outcomes included the day-90 Cerebral Performance Category (CPC) and the 48-h serum neurofilament light-chain (NF-L) level.

Results

We randomized 50 patients. The median IL6 area-under-the-curve was similar between the two groups (12,389 [7256–37,200] vs. 8859 [6825–18,088] pg/mL h; P = 0.55). No significant difference was noted in proportions of patients with favorable day-90 CPC scores (13/25 patients at 0.25 °C/h (52.0%; 95% CI 31.3–72.2%) and 13/25 patients at 0.50 °C/h (52.0%; 95% CI 31.3–72.2%; P = 0.99)). Median NF-L levels were not significantly different between the 0.25 °C/h and 0.50 °C/h groups (76.0 pg mL, [25.5–3074.0] vs. 192 pg mL, [33.6–4199.0]; P = 0.43; respectively).

Conclusion

In our RCT, rewarming from 33 °C at 0.25 °C/h, compared to 0.50 °C/h, did not decrease the serum IL6 level after shockable CA. Further RCTs are needed to better define the optimal TTM strategy for patients with CA.

Take-Home Message: Rewarming at a rate of 0.25 °C/h, compared to 0.50 °C, did not result in lower serum IL6 levels after achievement of hypothermia at 33 °C in patients who remained comatose after shockable cardiac arrest. No associations were found between the slower rewarming rate and day-90 functional outcomes or mortality.

140-character Tweet: Rewarming at 0.25 °C versus 0.50 °C did not decrease serum IL6 levels after hypothermia at 33 °C in patients comatose after shockable cardiac arrest.

 

Flow Index accurately identifies breaths with low or high inspiratory effort during pressure support ventilation

 

by Filippo Albani, Federica Fusina, Gianni Ciabatti, Luigi Pisani, Valeria Lippolis, Maria Elena Franceschetti, Alessia Giovannini, Rossella di Mussi, Francesco Murgolo, Antonio Rosano, Salvatore Grasso and Giuseppe Natalini 

 

Critical Care volume 25, Article number: 427 (2021) Published: 15 December 2021

Background

Flow Index, a numerical expression of the shape of the inspiratory flow-time waveform recorded during pressure support ventilation, is associated with patient inspiratory effort. The aim of this study was to assess the accuracy of Flow Index in detecting high or low inspiratory effort during pressure support ventilation and to establish cutoff values for the Flow index to identify these conditions. The secondary aim was to compare the performance of Flow index,of breathing pattern parameters and of airway occlusion pressure (P0.1) in detecting high or low inspiratory effort during pressure support ventilation.

Methods

Data from 24 subjects was included in the analysis, accounting for a total of 702 breaths. Breaths with high inspiratory effort were defined by a pressure developed by inspiratory muscles (Pmusc) greater than 10 cmH2O while breaths with low inspiratory effort were defined by a Pmusc lower than 5 cmH2O. The areas under the receiver operating characteristic curves of Flow Index and respiratory rate, tidal volume,respiratory rate over tidal volume and P0.1 were analyzed and compared to identify breaths with low or high inspiratory effort.

Results

Pmusc, P0.1, Pressure Time Product and Flow Index differed between breaths with high, low and intermediate inspiratory effort, while RR, RR/VT and VT/kg of IBW did not differ in a statistically significant way. A Flow index higher than 4.5 identified breaths with high inspiratory effort [AUC 0.89 (CI 95% 0.85–0.93)], a Flow Index lower than 2.6 identified breaths with low inspiratory effort [AUC 0.80 (CI 95% 0.76–0.83)].

Conclusions

Flow Index is accurate in detecting high and low spontaneous inspiratory effort during pressure support ventilation.

 

A guide to enteral nutrition in intensive care units: 10 expert tips for the daily practice

 

by Jean-Charles Preiser, Yaseen M. Arabi, Mette M. Berger, Michael Casaer, Stephen McClave, Juan C. Montejo-González, Sandra Peake, Annika Reintam Blaser, Greet Van den Berghe, Arthur van Zanten, Jan Wernerman and Paul Wischmeyer 

 

Critical Care volume 25, Article number: 424 (2021) Published: 14 December 2021

The preferential use of the oral/enteral route in critically ill patients over gut rest is uniformly recommended and applied. This article provides practical guidance on enteral nutrition in compliance with recent American and European guidelines. Low-dose enteral nutrition can be safely started within 48 h after admission, even during treatment with small or moderate doses of vasopressor agents. A percutaneous access should be used when enteral nutrition is anticipated for ≥ 4 weeks. Energy delivery should not be calculated to match energy expenditure before day 4–7, and the use of energy-dense formulas can be restricted to cases of inability to tolerate full-volume isocaloric enteral nutrition or to patients who require fluid restriction. Low-dose protein (max 0.8 g/kg/day) can be provided during the early phase of critical illness, while a protein target of > 1.2 g/kg/day could be considered during the rehabilitation phase. The occurrence of refeeding syndrome should be assessed by daily measurement of plasma phosphate, and a phosphate drop of 30% should be managed by reduction of enteral feeding rate and high-dose thiamine. Vomiting and increased gastric residual volume may indicate gastric intolerance, while sudden abdominal pain, distension, gastrointestinal paralysis, or rising abdominal pressure may indicate lower gastrointestinal intolerance.

 

Lung histopathologic clusters in severe COVID-19: a link between clinical picture and tissue damage

 

by Maddalena Alessandra Wu, Gianluca Lopez, Manuela Nebuloni, Davide Ottolina, Jonathan Montomoli, Luca Carsana, Tommaso Fossali, Antonio Castelli, Roberto Rech, Chiara Cogliati, Emanuele Catena and Riccardo Colombo

Critical Care volume 25, Article number: 423 (2021) Published: 13 December 2021

Background

Autoptic pulmonary findings have been described in severe COVID-19 patients, but evidence regarding the correlation between clinical picture and lung histopathologic patterns is still weak.

Methods

This was a retrospective cohort observational study conducted at the referral center for infectious diseases in northern Italy. Full lung autoptic findings and clinical data of patients who died from COVID-19 were analyzed. Lung histopathologic patterns were scored according to the extent of tissue damage. To consider coexisting histopathologic patterns, hierarchical clustering of histopathologic findings was applied.

Results

Whole pulmonary examination was available in 75 out of 92 full autopsies. Forty-eight hospitalized patients (64%), 44 from ICU and four from the medical ward, had complete clinical data. The histopathologic patterns had a time-dependent distribution with considerable overlap among patterns. Duration of positive-pressure ventilation (p < 0.0001), mean positive end-expiratory pressure (PEEP) (p = 0.007), worst serum albumin (p = 0.017), interleukin 6 (p = 0.047), and kidney SOFA (p = 0.001) differed among histopathologic clusters. The amount of PEEP for long-lasting ventilatory treatment was associated with the cluster showing the largest areas of early and late proliferative diffuse alveolar damage. No pharmacologic interventions or comorbidities affected the lung histopathology.

Conclusions

Our study draws a comprehensive link between the clinical and pulmonary histopathologic findings in a large cohort of COVID-19 patients. These results highlight that the positive end-expiratory pressures and the duration of the ventilatory treatment correlate with lung histopathologic patterns, providing new clues to the knowledge of the pathophysiology of severe SARS-CoV-2 pneumonia.

 

Predicting 90-day survival of patients with COVID-19: Survival of Severely Ill COVID (SOSIC) scores

by Matthieu Schmidt, Bertrand Guidet, Alexandre Demoule, Maharajah Ponnaiah, Muriel Fartoukh, Louis Puybasset, Alain Combes and David Hajage 

Annals of Intensive Care volume 11, Article number: 170 (2021) Published: 11 December 2021

 Background

Predicting outcomes of critically ill intensive care unit (ICU) patients with coronavirus-19 disease (COVID-19) is a major challenge to avoid futile, and prolonged ICU stays.

Methods

The objective was to develop predictive survival models for patients with COVID-19 after 1-to-2 weeks in ICU. Based on the COVID–ICU cohort, which prospectively collected characteristics, management, and outcomes of critically ill patients with COVID-19. Machine learning was used to develop dynamic, clinically useful models able to predict 90-day mortality using ICU data collected on day (D) 1, D7 or D14.

Results

Survival of Severely Ill COVID (SOSIC)-1, SOSIC-7, and SOSIC-14 scores were constructed with 4244, 2877, and 1349 patients, respectively, randomly assigned to development or test datasets. The three models selected 15 ICU-entry variables recorded on D1, D7, or D14. Cardiovascular, renal, and pulmonary functions on prediction D7 or D14 were among the most heavily weighted inputs for both models. For the test dataset, SOSIC-7’s area under the ROC curve was slightly higher (0.80 [0.74–0.86]) than those for SOSIC-1 (0.76 [0.71–0.81]) and SOSIC-14 (0.76 [0.68–0.83]). Similarly, SOSIC-1 and SOSIC-7 had excellent calibration curves, with similar Brier scores for the three models.

Conclusion

The SOSIC scores showed that entering 15 to 27 baseline and dynamic clinical parameters into an automatable XGBoost algorithm can potentially accurately predict the likely 90-day mortality post-ICU admission (sosic.shinyapps.io/shiny). Although external SOSIC-score validation is still needed, it is an additional tool to strengthen decisions about life-sustaining treatments and informing family members of likely prognosis.

 

 

 

 

Impact of the COVID-19 pandemic on the epidemiology of out-of-hospital cardiac arrest: a systematic review and meta-analysis

 

by Seth En Teoh, Yoshio Masuda, Darren Jun Hao Tan, Nan Liu, Laurie J. Morrison, Marcus Eng Hock Ong, Audrey L. Blewer and Andrew Fu Wah Ho 

 

Annals of Intensive Care volume 11, Article number: 169 (2021) Published: 07 December 2021

 

Background

The coronavirus disease 2019 (COVID-19) pandemic has significantly influenced epidemiology, yet its impact on out-of-hospital cardiac arrest (OHCA) remains unclear. We aimed to evaluate the impact of the pandemic on the incidence and case fatality rate (CFR) of OHCA. We also evaluated the impact on intermediate outcomes and clinical characteristics.

Methods

PubMed, EMBASE, Web of Science, Scopus, and Cochrane Library databases were searched from inception to May 3, 2021. Studies were included if they compared OHCA processes and outcomes between the pandemic and historical control time periods. Meta-analyses were performed for primary outcomes [annual incidence, mortality, and case fatality rate (CFR)], secondary outcomes [field termination of resuscitation (TOR), return of spontaneous circulation (ROSC), survival to hospital admission, and survival to hospital discharge], and clinical characteristics (shockable rhythm and etiologies). This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42021253879).

Results

The COVID-19 pandemic was associated with a 39.5% increase in pooled annual OHCA incidence (p < 0.001). Pooled CFR was increased by 2.65% (p < 0.001), with a pooled odds ratio (OR) of 1.95 for mortality [95% confidence interval (95%CI) 1.51–2.51]. There was increased field TOR (OR = 2.46, 95%CI 1.62–3.74). There were decreased ROSC (OR = 0.65, 95%CI 0.55–0.77), survival to hospital admission (OR = 0.65, 95%CI 0.48–0.89), and survival to discharge (OR = 0.52, 95%CI 0.40–0.69). There was decreased shockable rhythm (OR = 0.73, 95%CI 0.60–0.88) and increased asphyxial etiology of OHCA (OR = 1.17, 95%CI 1.02–1.33).

Conclusion

Compared to the pre-pandemic period, the COVID-19 pandemic period was significantly associated with increased OHCA incidence and worse outcomes.

 

Automated left atrial strain analysis for predicting atrial fibrillation in severe COVID-19 pneumonia: a prospective study

by Christophe Beyls, Alexis Hermida, Yohann Bohbot, Nicolas Martin, Christophe Viart, Solenne Boisgard, Camille Daumin, Pierre Huette, Hervé Dupont, Osama Abou-Arab and Yazine Mahjoub 

Annals of Intensive Care volume 11, Article number: 168 (2021) Published: 07 December 2021

Background

Atrial fibrillation (AF) is the most documented arrhythmia in COVID-19 pneumonia. Left atrial (LA) strain (LAS) analysis, a marker of LA contractility, have been associated with the development of AF in several clinical situations. We aimed to assess the diagnostic ability of LA strain parameters to predict AF in patients with severe hypoxemic COVID-19 pneumonia. We conducted a prospective single center study in Amiens University Hospital intensive care unit (ICU) (France). Adult patients with severe or critical COVID-19 pneumonia according to the World Health Organization definition and in sinus rhythm were included. Transthoracic echocardiography was performed within 48 h of ICU admission. LA strain analysis was performed by an automated software. The following LA strain parameters were recorded: LA strain during reservoir phase (LASr), LA strain during conduit phase (LAScd) and LA strain during contraction phase (LASct). The primary endpoint was the occurrence of AF during ICU stay.

Results

From March 2020 to February of 2021, 79 patients were included. Sixteen patients (20%) developed AF in ICU. Patients of the AF group were significantly older with a higher SAPS II score than those without AF. LAScd and LASr were significantly more impaired in the AF group compared to the other group (− 8.1 [− 6.3; − 10.9] vs. − 17.2 [− 5.0; − 10.2] %; P < 0.001 and 20.2 [12.3;27.3] % vs. 30.5 [23.8;36.2] %; P = 0.002, respectively), while LASct did not significantly differ between groups (p = 0.31). In a multivariate model, LAScd and SOFA cv were significantly associated with the occurrence of AF. A LAScd cutoff value of − 11% had a sensitivity of 76% and a specificity of 75% to identify patients with AF. The 30-day cumulative risk of AF was 42 ± 9% with LAScd > − 11% and 8 ± 4% with LAScd ≤ − 11% (log rank test P value < 0.0001).

Conclusion

For patients with severe COVID-19 pneumonia, development of AF during ICU stay is common (20%). LAS parameters seem useful in predicting AF within the first 48 h of ICU admission.

 

Development of a new score for early mortality prediction in trauma ICU patients: RETRASCORE

 

by Luis Serviá, Juan Antonio Llompart-Pou, Mario Chico-Fernández, Neus Montserrat, Mariona Badia, Jesús Abelardo Barea-Mendoza, María Ángeles Ballesteros-Sanz and Javier Trujillano 

 

Critical Care volume 25, Article number: 420 (2021) Published: 07 December 2021

Background

Severity scores are commonly used for outcome adjustment and benchmarking of trauma care provided. No specific models performed only with critically ill patients are available. Our objective was to develop a new score for early mortality prediction in trauma ICU patients.

Methods

This is a retrospective study using the Spanish Trauma ICU registry (RETRAUCI) 2015–2019. Patients were divided and analysed into the derivation (2015–2017) and validation sets (2018–2019). We used as candidate variables to be associated with mortality those available in RETRAUCI that could be collected in the first 24 h after ICU admission. Using logistic regression methodology, a simple score (RETRASCORE) was created with points assigned to each selected variable. The performance of the model was carried out according to global measures, discrimination and calibration.

Results

The analysis included 9465 patients: derivation set 5976 and validation set 3489. Thirty-day mortality was 12.2%. The predicted probability of 30-day mortality was determined by the following equation: 1/(1 + exp (− y)), where y = 0.598 (Age 50–65) + 1.239 (Age 66–75) + 2.198 (Age > 75) + 0.349 (PRECOAG) + 0.336 (Pre-hospital intubation) + 0.662 (High-risk mechanism) + 0.950 (unilateral mydriasis) + 3.217 (bilateral mydriasis) + 0.841 (Glasgow ≤ 8) + 0.495 (MAIS-Head) − 0.271 (MAIS-Thorax) + 1.148 (Haemodynamic failure) + 0.708 (Respiratory failure) + 0.567 (Coagulopathy) + 0.580 (Mechanical ventilation) + 0.452 (Massive haemorrhage) − 5.432. The AUROC was 0.913 (0.903–0.923) in the derivation set and 0.929 (0.918–0.940) in the validation set.

Conclusions

The newly developed RETRASCORE is an early, easy-to-calculate and specific score to predict in-hospital mortality in trauma ICU patients. Although it has achieved adequate internal validation, it must be externally validated.

 

 

 

 

Clinical characteristics and risk factors associated with mortality in patients with severe community-acquired pneumonia and type 2 diabetes mellitus

 

by Dong Huang, Dingxiu He, Linjing Gong, Wen Wang, Lei Yang, Zhongwei Zhang, Yujun Shi and Zongan Liang 

 

Critical Care volume 25, Article number: 419 (2021) Published: 07 December 2021

 

Background

The present study was performed to investigate the impacts of type 2 diabetes mellitus (T2DM) on severe community-acquired pneumonia (SCAP) and to develop a novel prediction model for mortality in SCAP patients with T2DM.

Methods

This was a retrospective observational study conducted in consecutive adult patients with SCAP admitted to the intensive care unit (ICU) of West China Hospital, Sichuan University, China, between September 2011 and September 2019. The primary outcome was hospital mortality. A propensity score matching (PSM) analysis model with a 1:2 ratio was used for the comparisons of clinical characteristics and outcomes between T2DM and nondiabetic patients. The independent risk factors were identified via univariate and then multivariable logistic regression analysis and were then used to establish a nomogram.

Results

In total, 1262 SCAP patients with T2DM and 2524 matched patients without T2DM were included after PSM. Patients with T2DM had longer ICU length of stay (LOS) (13 vs. 12 days, P = 0.016) and higher 14-day mortality (15% vs. 10.8%, P < 0.001), 30-day mortality (25.7% vs. 22.7%, P = 0.046), ICU mortality (30.8% vs. 26.5%, P = 0.005), and hospital mortality (35.2% vs. 31.0%, P = 0.009) than those without T2DM. In SCAP patients with T2DM, the independent risk factors for hospital mortality were increased numbers of comorbidities and diabetes-related complications; elevated C-reactive protein (CRP), neutrophil to lymphocyte ratio (NLR), brain natriuretic peptide (BNP) and blood lactate; as well as decreased blood pressure on admission. The nomogram had a C index of 0.907 (95% CI: 0.888, 0.927) in the training set and 0.873 (95% CI: 0.836, 0.911) in the testing set, which was superior to the pneumonia severity index (PSI, AUC: 0.809, 95% CI: 0.785, 0.833). The calibration curve and decision curve analysis (DCA) also demonstrated its accuracy and applicability.

Conclusions

SCAP patients with T2DM had worse clinical outcomes than nondiabetic patients. The nomogram has good predictive performance for hospital mortality and might be generally applied after more external validations.

 

Efficacy of non-invasive and invasive respiratory management strategies in adult patients with acute hypoxaemic respiratory failure: a systematic review and network meta-analysis

 

by Masaaki Sakuraya, Hiromu Okano, Tomoyuki Masuyama, Shunsuke Kimata and Satoshi Hokari 

 

Critical Care volume 25, Article number: 414 (2021) 

 

Background

Although non-invasive respiratory management strategies have been implemented to avoid intubation, patients with de novo acute hypoxaemic respiratory failure (AHRF) are high risk of treatment failure. In the previous meta-analyses, the effect of non-invasive ventilation was not evaluated according to ventilation modes in those patients. Furthermore, no meta-analyses comparing non-invasive respiratory management strategies with invasive mechanical ventilation (IMV) have been reported. We performed a network meta-analysis to compare the efficacy of non-invasive ventilation according to ventilation modes with high-flow nasal oxygen (HFNO), standard oxygen therapy (SOT), and IMV in adult patients with AHRF.

Methods

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. Studies including adults with AHRF and randomized controlled trials (RCTs) comparing two different respiratory management strategies (continuous positive airway pressure (CPAP), pressure support ventilation (PSV), HFNO, SOT, or IMV) were reviewed.

Results

We included 25 RCTs (3,302 participants: 27 comparisons). Using SOT as the reference, CPAP (risk ratio [RR] 0.55; 95% confidence interval [CI] 0.31–0.95; very low certainty) was associated significantly with a lower risk of mortality. Compared with SOT, PSV (RR 0.81; 95% CI 0.62–1.06; low certainty) and HFNO (RR 0.90; 95% CI 0.65–1.25; very low certainty) were not associated with a significantly lower risk of mortality. Compared with IMV, no non-invasive respiratory management was associated with a significantly lower risk of mortality, although all certainties of evidence were very low. The probability of being best in reducing short-term mortality among all possible interventions was higher for CPAP, followed by PSV and HFNO; IMV and SOT were tied for the worst (surface under the cumulative ranking curve value: 93.2, 65.0, 44.1, 23.9, and 23.9, respectively).

Conclusions

When performing non-invasive ventilation among patients with de novo AHRF, it is important to avoid excessive tidal volume and lung injury. Although pressure support is needed for some of these patients, it should be applied with caution because this may lead to excessive tidal volume and lung injury.