Time-varying intensity of oxygen exposure is associated with mortality in critically ill patients with mechanical ventilation

Mortality rate analysis of patients on invasive mechanical ventilation in the intensive care unit on day 28

Outcomes in patients receiving invasive mechanical ventilation (IMV) are currently unclear. The present study aimed to explore the prognostic factors of the mortality rate on day 28 in patients treated in the intensive care unit (ICU) and undergoing IMV. The IMV Mortality Prediction Score (IMPRES) of 129 patients in the ICU receiving IMV after emergency (or selective) endotracheal intubation from March 2018 to August 2020 was calculated. The patients were divided into survival (n=73) and death groups (n=56) on day 28. The predictive factors of independent and combined mortality rates were determined using a receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC). The AUC of the IMPRES for predicting patient death on day 28 was 0.785 (95% confidence interval (CI): 0.704-0.864, P<0.01). When the IMPRES cut-off was 4.50, the Youden index was at its maximum (0.487) with a sensitivity of 85.7% and a specificity of 63.0%. The AUC of the ventilator use time (days) at 12.5 days cut-off was 0.653 (95% CI: 0.56-0.746, P<0.01), the Youden index was 0.235 with a sensitivity of 52.1% and a specificity of 71.4%. The AUC of the IMPRES combined with the duration of ventilator use was 0.856 (95% CI: 0.789-0.922, P<0.001), the Youden index was 0.635 with a sensitivity of 84.9% and a specificity of 78.6%. The IMPRES was observed to be the main factor influencing the mortality rate of patients receiving IMV at the ICU on day 28, and the IMPRES combined with the duration of ventilator use had a significant predictive value for the 28-day mortality rates of these patients.

The neutrophil-to-lymphocyte ratio levels over time correlate to all-cause hospital mortality in sepsis

Objective

This research aims to investigate the prognosis value using the time-weighted average neutrophil-to-lymphocyte ratio (TWA-NLR) for predicting all-cause hospital mortality among sepsis patients. Data were analyzed through the use of the eICU Collaborative Research Database (eICU-CRD 2.0) as well as Medical Information Mart for Intensive Care IV 2.2 (MIMIC-IV 2.2).

Methods

Septic patients from both eICU-CRD 2.0 as well as MIMIC-IV 2.2 databases were included. The neutrophil-to-lymphocyte ratios (NLR) were available for analysis, utilizing complete blood counts obtained on days one, four, and seven following ICU admission. The TWA-NLR was computed at the end of the seven days, and patients were then stratified based on TWA-NLR thresholds. 90-day all-cause mortality during hospitalization was the primary objective, with 60-day all-cause hospital mortality as a secondary objective. The correlation between TWA-NLR and sepsis patients' primary outcome was analyzed using univariable and multivariable Cox proportional hazard regressions. A restricted cubic spline (RCS) analysis was conducted in an attempt to confirm this association further, and subgroup analyses were employed to evaluate the correlation across various comorbidity groups.

Results

3921 patients were included from the eICU-CRD 2.0, and the hospital mortality rate was 20.8 %. Both multivariable as well as univariable Cox proportional hazard regression analyses revealed that TWA-NLR was independently correlated with 90-day all-cause hospital mortality, yielding a hazard ratio (HR) of 1.02 (95 % CI 1.01-1.02, P-value<0.01) as well as 1.12 (95 % CI 1.01-1.15, P-value<0.01), respectively. The RCS analysis demonstrated a significant nonlinear relationship between TWA-NLR and 90-day all-cause hospital mortality risk. The study subjects were divided into higher (>10.5) and lower (≤10.5) TWA-NLR cohorts. A significantly decreased incidence of 90-day all-cause hospital mortality (HR = 0.56, 95 % CI 0.48-0.64, P-value<0.01) and longer median survival time (40 days vs 24 days, P-value<0.05) were observed in the lower TWA-NLR cohort. However, septic patients with chronic pulmonary (interaction of P-value = 0.009) or renal disease (interaction of P-value = 0.008) exhibited significant interactive associations between TWA-NLR and 90-day all-cause hospital mortality, suggesting the predictive power of TWA-NLR may be limited in these subgroups. The MIMIC-IV 2.2 was utilized as a validation cohort and exhibited a similar pattern.

Conclusion

Our findings suggest that TWA-NLR is a powerful and independent prognostic indicator for 90-day all-cause hospital mortality among septic patients, and the TWA-NLR cutoff value may prove a useful method for identifying high-risk septic patients.

The association between frailty and the risk of mortality in critically ill congestive heart failure patients: findings from the MIMIC-IV database

Background

Frailty is a severe, common co-morbidity associated with congestive heart failure (CHF). This retrospective cohort study assesses the association between frailty and the risk of mortality in critically ill CHF patients.

Methods

Eligible patients with CHF from the Medical Information Base for Intensive Care IV database were retrospectively analyzed. The frailty index based on laboratory tests (FI_Lab) index was calculated using 33 variables to assess frailty status. The primary outcomes were in-hospital mortality and one-year mortality. The secondary outcomes were the incidence of acute kidney injury (AKI) and the administration of renal replacement therapy (RRT) in patients with concurrent AKI. Survival disparities among the FI_Lab subgroups were estimated with Kaplan-Meier survival analysis. The association between the FI_Lab index and mortality was examined with Cox proportional risk modeling.

Results

A total of 3273 adult patients aged 18 years and older were enrolled in the study, with 1820 men and 1453 women included. The incidence rates of in-hospital mortality and one-year mortality rate were 0.96 per 1,000 person-days and 263.8 per 1,000 person-years, respectively. Multivariable regression analysis identified baseline FI_Lab > 0.45 as an independent risk factor predicting in-hospital mortality (odds ratio = 3.221, 95% CI 2.341-4.432, p < 0.001) and one-year mortality (hazard ratio=2.152, 95% CI: 1.730-2.678, p < 0.001). In terms of predicting mortality, adding FI_Lab to the six disease severity scores significantly improved the overall performance of the model (all p < 0.001).

Conclusions

We established a positive correlation between the baseline FI_Lab and the likelihood of adverse outcomes in critical CHF patients. Given its potential as a reliable prognostic tool for such patients, further validation of FI_Lab across multiple centers is recommended for future research.

Clinical phenotypes and short-term outcomes based on prehospital point-of-care testing and on-scene vital signs

Emergency medical services (EMSs) face critical situations that require patient risk classification based on analytical and vital signs. We aimed to establish clustering-derived phenotypes based on prehospital analytical and vital signs that allow risk stratification. This was a prospective, multicenter, EMS-delivered, ambulance-based cohort study considering six advanced life support units, 38 basic life support units, and four tertiary hospitals in Spain. Adults with unselected acute diseases managed by the EMS and evacuated with discharge priority to emergency departments were considered between January 1, 2020, and June 30, 2023. Prehospital point-of-care testing and on-scene vital signs were used for the unsupervised machine learning method (clustering) to determine the phenotypes. Then phenotypes were compared with the primary outcome (cumulative mortality (all-cause) at 2, 7, and 30 days). A total of 7909 patients were included. The median (IQR) age was 64 (51-80) years, 41% were women, and 26% were living in rural areas. Three clusters were identified: alpha 16.2% (1281 patients), beta 28.8% (2279), and gamma 55% (4349). The mortality rates for alpha, beta and gamma at 2 days were 18.6%, 4.1%, and 0.8%, respectively; at 7 days, were 24.7%, 6.2%, and 1.7%; and at 30 days, were 33%, 10.2%, and 3.2%, respectively. Based on standard vital signs and blood test biomarkers in the prehospital scenario, three clusters were identified: alpha (high-risk), beta and gamma (medium- and low-risk, respectively). This permits the EMS system to quickly identify patients who are potentially compromised and to proactively implement the necessary interventions.

Association Between Early Hyperoxemia Exposure and Intensive Care Unit Mortality in Intracerebral Hemorrhage: An Observational Cohort Analysis

BACKGROUND

Supraphysiologic levels of oxygen could have potential adverse effects on the brain that may be dose and time dependent in patients with brain injury. We therefore aimed to assess whether exposure to excess supplemental oxygen, measured as time-weighted mean exposure to hyperoxemia, was associated with intensive care unit (ICU) mortality in patients with intracerebral hemorrhage (ICH).

METHODS

In this single-center retrospective cohort study, we included all patients admitted to our ICU with a diagnosis of primary spontaneous ICH. To provide a longitudinal measure of hyperoxemia exposure, we calculated the hyperoxemia dose, defined as the area under the partial pressure of oxygen in arterial blood (PaO2) time curve above the threshold PaO2 value of 100 mm Hg (13.3 kPa) divided by the number of hours of potential exposure. To provide consistent potential exposure windows and limit bias from informative censoring, nested subsets were created with progressively longer exposure periods (0-1 day, 0-2 days, 0-3 days, 0-4 days, 0-5 days, 0-6 days, 0-7 days). We used multivariable Cox regression, with hyperoxemia dose as a time-dependent covariate, to model ICU mortality. Admission ICH and Acute Physiology and Chronic Health Evaluation II scores were included as predictor covariables. A step-function extended Cox model was also fitted.

RESULTS

Between September 2019 and July 2022, 275 patients met the inclusion criteria, with 24,588 arterial blood gas results available for analysis. The mean age was 57.19 years (± 13.99), 59.64% were male, 23.64% had an infratentorial origin of hemorrhage, and ICU mortality was 35.64%. Almost all patients (97.45%) were exposed to hyperoxemia during their ICU admission. Cox regression modeling showed an association between hyperoxemia dose and ICU mortality (hazard ratio 1.15, confidence interval 1.05-1.25, p = 0.003). This association was observed in the 0-1 day subset in the step-function extended Cox model (hazard ratio 1.19, confidence interval 1.06-1.35, p = 0.005) but not in any of the subsequent exposure periods.

CONCLUSIONS

In patients with ICH admitted to the ICU, we observed an association between hyperoxemia dose and ICU mortality. Further prospective study is required to inform guidance on early systemic oxygen targets in ICH.

Advanced Respiratory Support Days as a Novel Marker of Mortality in COVID-19 Acute Respiratory Distress Syndrome Requiring Extracorporeal Membrane Oxygenation

Emerging evidence suggests prolonged use of noninvasive respiratory support may increase mortality of patients with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome who require extracorporeal membrane oxygenation (ECMO). Using a database of adults receiving ECMO for COVID-19, we calculated survival curves and multivariable Cox regression to determine the risk of death associated with pre-ECMO use of high-flow nasal oxygen (HFNO), noninvasive ventilation (NIV), and invasive mechanical ventilation (IMV) days. We investigated the performance of a novel variable, advanced respiratory support days (composite of HFNO, NIV, and IMV days), on Respiratory ECMO Survival Prediction (RESP) score. Subjects (N = 146) with increasing advanced respiratory support days (<5, 5-9, and ≥10) had a stepwise increase in 90 day mortality (32.2%, 57.7%, and 75.4%, respectively; p = 0.002). Ninety-day mortality was significantly higher in subjects (N = 121) receiving NIV >4 days (81.8% vs. 52.4%, p < 0.001). Each additional pre-ECMO advanced respiratory support day increased the odds of right ventricular failure (odds ratio [OR]: 1.066, 95% confidence interval [CI]: 1.002-1.135) and in-hospital mortality (1.17, 95% CI: 1.08-1.27). Substituting advanced respiratory support days for IMV days improved RESP score mortality prediction (area under the curve (AUC) or: 0.64 vs. 0.71). Pre-ECMO advanced respiratory support days were associated with increased 90 day mortality compared with IMV days alone. Adjusting the RESP score for advanced respiratory support days improved mortality prediction.

U-Shaped Association between Serum Chloride Levels and In-Hospital Mortality in Patients with Congestive Heart Failure in Intensive Care Units

Serum chloride level has clinical significance in the prognosis of heart failure. Little is known regarding the association between serum chloride levels and in-hospital mortality in patients with heart failure.This retrospective study used clinical data obtained from the Medical Information Mart for Intensive Care Database. The study cohort comprised patients who were categorized on the basis of their serum chloride levels, and the primary endpoint was in-hospital mortality. To assess the impact of serum chloride levels at the time of intensive care unit admission on in-hospital mortality, we used various statistical approaches, including multivariable logistic regression models, a generalized additive model, and a two-piecewise linear regression model. In addition, subgroup analysis was conducted to examine the robustness of the main findings.This study comprised 15,983 participants. When compared with the reference group (Q5), the groups with the highest (Q7) and lowest (Q1) blood chloride levels exhibited increased in-hospital mortality, with fully adjusted odds ratios (ORs) of 1.36 [95% confidence interval (CI): 1.08-1.71] and 1.25 (95% CI: 1-1.56), respectively. A U-shaped relationship was observed between blood chloride levels and in-hospital mortality, with the lowest risk observed at a threshold of 105.017 mmol/L. The effect sizes and corresponding CIs below and above the threshold were 0.969 (95% CI: 0.957-0.982) and 1.039 (95% CI: 1.002-1.076), respectively. Stratified analyses demonstrated the robustness of this correlation.The relationship between serum chloride levels and in-hospital mortality in patients with heart failure was U-shaped, with an inflection point of 105.017 mmol/L.

Early persistent exposure to high CVP is associated with increased mortality and AKI in septic shock: A retrospective study

PURPOSE

This study's objective was to investigate the association between exposure to different intensities of central venous pressure (CVP) over time in patients with septic shock with 28-day mortality and acute kidney injury (AKI).

MATERIALS AND METHODS

We obtained data from the AmsterdamUMCdb, which includes data on patients ≥18 years old with septic shock undergoing CVP monitoring. The primary outcome was mortality by day 28. Piecewise exponential additive mixed models were used to estimate the strength of the association over time.

RESULTS

9668 patients were included in the study. They exhibited 8.2% overall mortality at 28 days and 41.1% AKI incidence. Daily time-weighted average CVP was strongly associated with increased mortality at 28 days, primarily within 24 h of ICU admission. The mortality rate of patients was lowest when the CVP was 6-12 cmH2O. When the time of high CVP (TWA-CVP >12 cmH2O) exposure within the first 24 h was >5 h, the risk of death increased by 2.69-fold. Additionally, patients exposed to high CVP had a significantly increased risk of developing AKI.

CONCLUSIONS

The optimal CVP range for patients with septic shock within 24 h of ICU admission is 6-12 cmH2O. Mortality increased when patients were exposed to high CVP for >5 h.

The prognostic nutritional index predicts all-cause mortality in critically ill patients with acute myocardial infarction

BACKGROUND

Malnutrition is common in patients with acute myocardial infarction (AMI) and is associated with a poor prognosis. The prognostic value of the prognostic nutritional index (PNI) in patients with AMI remains controversial. We aimed to explore the relationship between PNI and all-cause mortality in critically ill patients with AMI and evaluate the incremental prognostic value of PNI to commonly used prognostic assessment tools.

METHODS

The Medical Information Mart for Intensive Care-IV (MIMIC-IV) database was used to conduct a retrospective cohort analysis on 1180 critically ill patients with AMI. The primary endpoints were defined as 6-month and 1-year all-cause mortality. Cox regression analysis was used to investigate the relationship between admission PNI and all-cause mortality. The effect of adding PNI to sequential organ failure assessment (SOFA) score, or charlson comorbidity index (CCI) on its discriminative ability was assessed using C-statistic, net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

RESULTS

Multivariate cox regression analysis demonstrated that the low PNI was regarded as an independent predictor of 1-year all-cause mortality in AMI patients admitted to ICU (adjusted Hazard Ratio: 95% CI = 1.75 (1.22-2.49)). The ROC test showed that admission PNI had a moderate predictive ability to predict all-cause mortality of critically ill patients with AMI. Furthermore, the net reclassification and integrated discrimination of the CCI alone model improved significantly with PNI. [C-statistic increased from 0.669 to 0.752, p < 0.001; NRI = 0.698, p < 0.001; IDI = 0.073, p < 0.001]. When PNI was added to the SOFA score, the C-statistic significantly improved from 0.770 to 0.805 (p < 0.001), and the NRI and IDI were estimated at 0.573 (p < 0.001) and 0.041 (p < 0.001), respectively.

CONCLUSION

PNI could be a novel predictor for identifying patients at high risk of 1-year all-cause mortality in critically ill patients with AMI. The addition of PNI to the SOFA score or CCI may be useful for very early risk stratification.

Effects of hyperoxemia in patients with sepsis - A post-hoc analysis of a multicentre randomized clinical trial

BACKGROUND

Administration of supplemental oxygen is a life-saving treatment in critically ill patients. Still, optimal dosing remains unclear during sepsis. The aim of this post-hoc analysis was to assess the association between hyperoxemia and 90-day mortality in a large cohort of septic patients.

METHODS

This is a post-hoc analysis of the Albumin Italian Outcome Sepsis (ALBIOS) randomized controlled trial (RCT). Patients with sepsis who survived the first 48 h since randomization were included and stratified into two groups according to their average PaO₂ levels during the first 48 h (PaO_{2 0-48 h}). The cut-off value was established at 100 mmHg (average PaO_{2 0-48 h} >100 mmHg: hyperoxemia group; PaO_{2 0-48h}≤100: normoxemia group). The primary outcome was 90-day mortality.

RESULTS

1632 patients were included in this analysis (661 patients in the hyperoxemia group, 971 patients in the normoxemia group). Concerning the primary outcome, 344 (35.4%) patients in the hyperoxemia group vs. 236 (35.7%) in the normoxemia group had died within 90 days from randomization (p = 0.909). No association was found after adjusting for confounders (HR 0.87; CI [95%] 0.736-1.028, p = 0.102) or after excluding patients with hypoxemia at enrollment, patients with lung infection or including post-surgical patients only. Conversely, we found an association between lower risk of 90-day mortality and hyperoxemia in the subgroup including patients who had the lung as primary site of infection (HR 0.72; CI [95%] 0.565-0.918). Mortality at 28 days, ICU mortality, incidence of acute kidney injury, use of renal replacement therapy, days to suspension of vasopressor or inotropic agents, and resolution of primary and secondary infections did not differ significantly. Duration of mechanical ventilation and length of stay in ICU were significantly longer in patients with hyperoxemia.

CONCLUSIONS

In a post-hoc analysis of a RCT enrolling septic patients, hyperoxemia as average PaO₂>100 mmHg during the first 48 h was not associated with patients' survival.

The Local and Systemic Exposure to Oxygen in Children With Severe Bronchiolitis on Invasive Mechanical Ventilation: A Retrospective Cohort Study

OBJECTIVES

Oxygen supplementation is a cornerstone treatment in critically ill children with bronchiolitis in the PICU. However, potential deleterious effects of high-dose oxygen are well-known. In this study, we aim to describe the pulmonary (local) and arterial (systemic) oxygen exposure over the duration of invasive mechanical ventilation (IMV) in children with severe bronchiolitis. Our secondary aim was to estimate potentially avoidable exposure to high-dose oxygen in these patients.

DESIGN

Retrospective cohort study.

SETTING

Single-center, tertiary-care PICU.

PATIENTS

Children younger than 2 years old admitted to the PICU for severe bronchiolitis receiving IMV.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Hourly measurements of Fio2 and peripheral oxygen saturation (Spo2), and arterial blood gas data were collected up to day 10 of IMV. A total of 24,451 hours of IMV were observed in 176 patients (median age of 1.0 mo [interquartile range (IQR), 1.0-2.3 mo]). The pulmonary exposure to oxygen was highest during the first day of IMV (median time-weighted average [TWA]-Fio2 0.46 [IQR, 0.39-0.53]), which significantly decreased over subsequent days. The systemic exposure to oxygen was relatively low, as severe hyperoxemia (TWA-Pao2 > 248 Torr [> 33 kPa]) was not observed. However, overuse of oxygen was common with 52.3% of patients (n = 92) having at least 1 day of possible excessive oxygen exposure and 14.8% (n = 26) with severe exposure. Furthermore, higher oxygen dosages correlated with increasing overuse of oxygen (rrepeated measures, 0.59; 95% CI, 0.54-0.63). Additionally, caregivers were likely to keep Fio2 greater than or equal to 0.50 when Spo2 greater than or equal to 97%.

CONCLUSIONS

Moderate to high-dose pulmonary oxygen exposure and potential overuse of oxygen were common in this cohort of severe bronchiolitis patients requiring IMV; however, this was not accompanied by a high systemic oxygen burden. Further studies are needed to determine optimal oxygenation targets to prevent overzealous use of oxygen in this vulnerable population.

The association of diastolic arterial pressure and heart rate with mortality in septic shock: a retrospective cohort study

BACKGROUND

The effects of diastolic arterial pressure (DAP) and heart rate (HR) on the prognosis of patients with septic shock are unclear, and whether these effects persist over time is unknown. We aimed to investigate the relationship between exposure to different intensities of DAP and HR over time and mortality at 28 days in patients with septic shock.

METHODS

In this cohort study, we obtained data from the Medical Information Mart for Intensive Care IV, which includes the data of adult patients (≥ 18 years) with septic shock who underwent invasive blood pressure monitoring. We excluded patients who received extracorporeal membrane oxygenation (ECMO) or glucocorticoids within 48 h of ICU admission. The primary outcome was mortality at 28 days. Piece-wise exponential additive mixed models were used to estimate the strength of the associations over time.

RESULTS

In total, 4959 patients were finally included. The median length of stay in the ICU was 3.2 days (IQR: 1.5-7.1 days), and the mortality in the ICU was 12.9%, with a total mortality at 28 days of 15.9%. After adjustment for baseline and time-dependent confounders, both daily time-weighted average (TWA) DAP and HR were associated with increased mortality at 28 days and strong association, mainly in the early to mid-stages of the disease. The results showed that mortality in patients with septic shock was lowest at a DAP of 50-70 mm Hg and an HR of 60-90 beats per minute (bpm). Throughout, a significant increase in the risk of death was found with daily exposure to TWA-DAP ≤ 40 mmHg (hazard ratio 0.99, 95% confidence interval (CI) 0.94-1.03) or TWA-HR ≥ 100 bpm (hazard ratio 1.16, 95% CI 1.1-1.21). Cumulative and interactive effects of harmful exposure (TWA-DAP ≤ 40 mmHg and TWA-HR ≥ 100 bpm) were also observed.

CONCLUSION

The optimal ranges for DAP and HR in patients with septic shock are 50-70 mmHg and 60-90 bpm, respectively. The cumulative and interactive effects of exposure to low DAP (≤ 40 mmHg) and tachycardia (≥ 100 bpm) were associated with an increased risk of death.

Frailty index based on laboratory tests improves prediction of short-and long-term mortality in patients with critical acute myocardial infarction

Background

Previous studies have shown that the frailty index based on laboratory tests (FI-Lab) can identify older adults at increased risk of adverse health outcomes. This study aimed to determine whether the FI-Lab is associated with mortality risk and can provide incremental improvements in risk stratification of patients with critical acute myocardial infarction (AMI).

Materials and methods

We conducted a secondary analysis of data from the Medical Information Mart for Intensive Care (MIMIC)-IV database. A 33-item FI-Lab was constructed. Outcomes of interest were in-hospital and 1-year mortality. Logistic regression models were used to investigate the association between the FI-Lab and outcomes. For the assessment of the incremental predictive value, the FI-Lab was added to several risk stratification scoring systems for critically ill patients, and the following indices were calculated: Δ C-statistic, integrated discrimination improvement (IDI), and net reclassification improvement (NRI).

Results

Out of 2,159 patients, 477 died in hospital (22.1%), and 898 died during the 1-year follow-up period. After adjustment for confounders, the FI-Lab was associated with increased in-hospital mortality [odds ratio (OR) = 1.06, 95% confidence interval (CI): 1.05-1.07] and 1-year mortality (OR = 1.05, 95% CI: 1.04-1.06) when assessed as a continuous variable (per 0.01-score increase). When assessed as a categorical variable, the FI-Lab was associated with in-hospital mortality (2nd Quartile: OR = 1.89, 95% CI: 1.18-3.03; 3rd Quartile: OR = 3.46, 95% CI: 2.20-5.46; and 4th Quartile: OR = 5.79, 95% CI: 3.61-9.28 compared to 1st Quartile) as well as 1-year mortality (2nd Quartile: OR = 1.66, 95% CI: 1.23-2.24; 3rd Quartile: OR = 2.40, 95% CI: 1.76-3.26; and 4th Quartile: OR = 3.76, 95% CI: 2.66-5.30 compared to 1st Quartile) after adjustment for confounders. The addition of the FI-Lab to all disease severity scores improved discrimination and significantly reclassified in-hospital and 1-year mortality risk.

Conclusion

The FI-Lab was a strong predictor of short- and long-term mortality in patients with critical AMI. The FI-Lab improved the ability to predict mortality in patients with critical AMI and therefore might be useful in the clinical decision-making process.