The Anion Gap is a Predictive Clinical Marker for Death in Patients with Acute Pesticide Intoxication

Association between Albumin-Corrected Anion Gap and Mortality in Patients with Cardiogenic Shock

Background

Cardiogenic shock (CS) is a critical illness with a high mortality rate in clinical practice. Although some biomarkers have been found to be associated with mortality in patients suffering from CS in previous studies. The albumin-corrected anion gap (ACAG) has not been studied in depth. Our study aimed to explore the relationship between ACAG and mortality in patients with CS.

Methods

All baseline data was extracted from Medical Information Mart for Intensive Care-IV version: 2.0 (MIMIC-IV). According to the prognosis at 30 days of follow-up, they were divided into survivors and non-survivors groups. The survival curves between the two groups were drawn using the Kaplan-Meier method and the log-rank test. Valid factors were selected using the least absolute shrinkage and selection operator (LASSO) logistic analysis model. Analysis was performed to investigate the relationship between mortality and all enrolled patients using restricted cubic spline (RCS) and Cox proportional hazards models. Receiver operating characteristic (ROC) curves were used to assess the predictive ability of ACAG. Evaluation of final result stability using sensitivity analysis.

Results

839 cases were selected to meet the inclusion criteria and categorized into survivors and non-survivors groups in the final analysis. The ACAG value measured for the first time at the time of admission was selected as the research object. Kaplan-Meier (K-M) survival curves showed that cumulative 30- and 90-day survival decreased progressively with elevated ACAG (p < 0.001), and multifactorial Cox regression analyses showed ACAG to be an independent risk factor for increased 30- and 90-day mortality in patients suffering from CS (p < 0.05). RCS curves revealed that all-cause mortality in this group of patients increased with increasing ACAG ( χ 2 = 5.830, p = 0.120). The ROC curve showed that the best cutoff value for ACAG for predicting 30-day mortality in patients with CS was 22.625, with a sensitivity of 44.0% and a specificity of 74.7%. The relationship between ACAG and CS short-term mortality remained stable in all sensitivity analyses (All p < 0.05).

Conclusions

The ACAG is an independent risk factor for 30- and 90-day mortality in CS patients and predicts poor clinical outcomes in CS patients. According to our study, elevated ACAG at admission, especially when ACAG > 20 mmol/L, was an independent predictor of all-cause mortality in CS.

Association Between Albumin-Corrected Anion Gap and In-Hospital Mortality and Sepsis-Associated Acute Kidney Injury

BACKGROUND This study aimed to investigate the association between albumin-corrected anion gap (ACAG) and in-hospital mortality in sepsis-associated acute kidney injury (S-AKI). MATERIAL AND METHODS We conducted this retrospective study based on data from the Medical Information Mart for Intensive Care IV database, and assessed the prognostic capabilities of ACAG in comparison with albumin (ALB) and anion gap (AG) to predict in-hospital mortality of patients with S-AKI. Binomial logistic regression analysis was performed to identify whether ACAG was an independent risk factor for in-hospital mortality for the patients, and receiver operating characteristic (ROC) curves were plotted to clarify its efficacy in predicting in-hospital mortality. We also performed a decision curve analysis (DCA) to determine whether there were net clinical benefits for patients when ACAG was used to predict in-hospital mortality. RESULTS Binary logistic regression analysis showed that ACAG was an independent risk factor for in-hospital mortality in patients with S-AKI, with an area under the ROC (AUC) curve of 0.675 (moderate predictive value) for the prediction of in-hospital mortality, higher than that of ALB or AG alone, with the highest Youden's index (0.2675). The DCA substantiated the superiority of ACAG in net clinical benefits at various threshold probability, enhancing its clinical applicability. CONCLUSIONS The research emphasizes the potential of ACAG as a valuable predictive tool for in-hospital mortality in S-AKI patients, which is better than albumin and AG, encouraging its consideration in clinical practice.

Preoperative albumin corrected anion gap is associated with in-hospital and long-term mortality in patients undergoing coronary artery bypass grafting in a retrospective cohort study

Background

Coronary artery disease remains a global health concern and the leading cause of death. Till today, coronary artery bypass grafting (CABG) is one of the main treatment strategies for coronary artery disease, especially for Multivessel coronary disease or complex coronary lesions. The present study aimed to explore the relationship of preoperative albumin corrected anion gap (ACAG) with mortality in all those patients who undergoing CABG.

Methods

All the patients undergoing CABG were included in the study. All clinical data were collected from CareVue and MetaVision system. The predictive value of ACAG for mortality was determined by receiver operating characteristic (ROC) curves survival curves were estimated using the Kaplan-Meier method. Multivariate regression models were constructed to determine the association of ACAG with mortality.

Results

A total of 2,180 patients were identified and divided into a high ACAG group (ACAG ≥16.0 mmol/L) and low ACAG group (ACAG <16.0 mmol/L) according to the ROC analysis. Patients in the high ACAG group were older and presented with more comorbidities and concomitant valvular surgeries. Further more, in the high ACAG group, we observed a higher length of stay in the intensive care unit [3.88 (2.15, 7.09) vs. 2.29 (1.29, 3.94), P<0.001]. Both the in-hospital mortality [28 (4.5%) vs. 11 (0.7%), P<0.001], and the 4-year mortality [125 (27.1%) vs. 111 (12.7%), P<0.001] were also rised in those patients. And it was also showed in the survival curves, patients with ACAG ≥16.0 mmol/L had a significant lower 4-year survival (P<0.001). While in the multivariate regression model, we found ACAG was act as an independent risk factor for both the in-hospital mortality [odds ratio (OR): 1.248 (1.060, 1.470), P=0.008] and the 4-year mortality [hazard ratio (HR): 1.134 (1.063, 1.210), P<0.001]. An ACAG ≥16.0 mmol/L was significantly associated with a 2.7-fold risk of in-hospital mortality [OR: 2.732 (1.129, 6.610), P=0.026].

Conclusions

Preoperative ACAG is an independent risk factor for in-hospital and long-term mortality in CABG patients. A higher ACAG may relate to severe coronary artery stenosis and cardiac dysfunction, which is more likely to lead to a postoperative systemic inflammatory response, microcirculation disorder, and subsequent complications.

Prediction Model of Acute Respiratory Failure in Patients with Acute Pesticide Poisoning by Intentional Ingestion: Prediction of Respiratory Failure in Pesticide Intoxication (PREP) Scores in Cohort Study

Acute respiratory failure is the primary cause of mortality in patients with acute pesticide poisoning. The aim of the present study was to develop a new and efficient score system for predicting acute respiratory failure in patients with acute pesticide poisoning. This study was a retrospective observational cohort study comprised of 679 patients with acute pesticide poisoning by intentional poisoning. We divided this population into a ratio of 3:1; training set (n = 509) and test set (n = 170) for model development and validation. Multivariable logistic regression models were used in developing a score-based prediction model. The Prediction of Respiratory failure in Pesticide intoxication (PREP) scoring system included a summation of the integer scores of the following five variables; age, pesticide category, amount of ingestion, Glasgow Coma Scale, and arterial pH. The PREP scoring system developed accurately predicted respiratory failure (AUC 0.911 [0.849−0.974], positive predictive value 0.773, accuracy 0.873 in test set). We came up with four risk categories (A, B, C and D) using PREP scores 20, 40 and 60 as the cut-off for mechanical ventilation requirement risk. The PREP scoring system developed in the present study could predict respiratory failure in patients with pesticide poisoning, which can be easily implemented in clinical situations. Further prospective studies are needed to validate the PREP scoring system.

Osmolal and anion gaps after acute self-poisoning with agricultural formulations of the organophosphorus insecticides profenofos and diazinon: A pilot study

Self-poisoning with organophosphorus (OP) insecticides is an important means of global self-harm. The insecticides are formulated with solvents that may also contribute to toxicity. We set up a study to detect changes in osmolal and anion gaps following ingestion of OP insecticides. We recruited consecutive patients admitted to a Teaching Hospital, Sri Lanka, with a history of OP self-poisoning. The osmolal and anion gaps were calculated on admission and at 4, 24 and 72 h post-ingestion together with ethanol concentration. Forty-nine patients were recruited (28 profenofos, 10 diazinon, one coumaphos, one chlorpyrifos, one phenthoate and eight unknown OP). Only modest increases in osmolal and anion gaps were noted. Small rises in osmolal gap above the upper limit of normal were noted in 16/49 (32.7%) of all cases, 9/28 (32.1%) profenofos cases and 4/10 (40.0%) diazinon cases. The anion gap was raised in 24/49 (49.0%) of all cases, 15/28 (53.6%) profenofos cases and 5/10 (50.0%) diazinon cases. We observed a trend for a fall in osmolal gap during the first 24 h, followed by an increase up to 72 h. There was no correlation between the anion gap and serum lactate concentration, indicating that a lactic acidosis was not responsible for the anion gap. Formate, which could have explained the increased gap, was not detected in any of the samples; ketoacids (beta-hydroxybutyrate and acetoacetate) were not measured. This pilot study found that profenofos and diazinon poisoning caused only modest increases in the osmolal and anion gaps in a minority of cases.

Albumin corrected anion gap for predicting in-hospital mortality among intensive care patients with sepsis: A retrospective propensity score matching analysis

BACKGROUND

The relationship between albumin corrected anion gap (ACAG) and in-hospital mortality of intensive care sepsis patients is currently inconclusive.

METHODS

The baseline data, concentration of albumin, anion gap (AG), ACAG and in-hospital prognosis of intensive care patients with sepsis were retrieved from the Medical Information Mart for Intensive Care IV database. Propensity score matching (PSM) analysis was performed to reduce bias. Receiver operating characteristic curves were drawn for albumin, AG, and ACAG, and comparisons between the areas under the ROC curves were conducted. Decision curve analysis (DCA) was performed to determine the net benefit of ACAG.

RESULTS

ACAG was related to in-hospital mortality in intensive care patients with sepsis. The AUCs of ACAG were 0.689 (before PSM) and 0.644 (after PSM), which were significantly higher than that of albumin or AG. The Youden's index of ACAG was the highest, and the net benefit range of ACAG was also the largest according to the DCA.

CONCLUSIONS

ACAG has the highest predictive value for in-hospital mortality of intensive care patients with sepsis, which is better than albumin and AG. Using ACAG to predict the in-hospital mortality to guide clinical applications may obtain the highest net benefit.

Impact of Acid-Base Status on Mortality in Patients with Acute Pesticide Poisoning

We investigated clinical impacts of various acid-base approaches (physiologic, base excess (BE)-based, and physicochemical) on mortality in patients with acute pesticide intoxication and mutual intercorrelated effects using principal component analysis (PCA). This retrospective study included patients admitted from January 2015 to December 2019 because of pesticide intoxication. We compared parameters assessing the acid-base status between two groups, survivors and non-survivors. Associations between parameters and 30-days mortality were investigated. A total of 797 patients were analyzed. In non-survivors, pH, bicarbonate concentration (HCO₃⁻), total concentration of carbon dioxide (tCO₂), BE, and effective strong ion difference (SIDe) were lower and apparent strong ion difference (SIDa), strong ion gap (SIG), total concentration of weak acids, and corrected anion gap (corAG) were higher than in survivors. In the multivariable logistic analysis, BE, corAG, SIDa, and SIDe were associated with mortality. PCA identified four principal components related to mortality. SIDe, HCO₃⁻, tCO₂, BE, SIG, and corAG were loaded to principal component 1 (PC1), referred as total buffer bases to receive and handle generated acids. PC1 was an important factor in predicting mortality irrespective of the pesticide category. PC3, loaded mainly with pCO₂, suggested respiratory components of the acid-base system. PC3 was associated with 30-days mortality, especially in organophosphate or carbamate poisoning. Our study showed that acid-base abnormalities were associated with mortality in patients with acute pesticide poisoning. We reduced these variables into four PCs, resembling the physicochemical approach, revealed that PCs representing total buffer bases and respiratory components played an important role in acute pesticide poisoning.

Diagnosis of acute intoxications in critically ill patients: focus on biomarkers - part 2: markers for specific intoxications

In medical intensive care units, acute intoxications contribute to a large proportion of all patients. Epidemiology and a basic overview on this topic were presented in part one. The purpose of this second part regarding toxicological biomarkers in the ICU setting focuses on specific poisons and toxins. Following the introduction of anion and osmol gap in part one, it's relevance in toxic alcohols and other biomarkers for these poisonings are presented within this publication. Furthermore, the role of markers in the blood, urine and cerebrospinal fluid for several intoxications is evaluated. Specific details are presented, amongst others, for cardiovascular drug poisoning, paracetamol (acetaminophen), ethanol, pesticides, ricin and yew tree intoxications. Detailed biomarkers and therapeutic decision tools are shown for carbon monoxide (CO) and cyanide (CN^-) poisoning. Also, biomarkers in environmental toxicological situations such as mushroom poisoning and scorpion stings are presented.

Diagnosis of acute intoxications in critically ill patients: focus on biomarkers - part 1: epidemiology, methodology and general overview

Acute intoxications account for a significant proportion of the patient population in intensive care units and sedative medications, ethanol, illicit drugs, inhalable poisons and mixed intoxications are the most common causes. The aim of this article is to describe biomarkers for screening and diagnosis of acute intoxications in critically ill patients. For this purpose, a survey of the relevant literature was conducted, and guidelines, case reports, expert assessments, and scientific publications were reviewed. In critical care, it should always be attempted to identify and quantify the poison or toxin with the assistance of enzyme immunoassay (EIA), chromatography, and mass spectrometry techniques and this section is critically appraised in this publication. The principles for anion gap, osmol gap and lactate gap and their usage in intoxications is shown. Basic rules in test methodology and pre-analytics are reviewed. Biomarkers in general are presented in part one and biomarkers for specific intoxications including ethanol, paracetamol, cardiovascular drugs and many others are presented in part two of these publications.

Novel Clinical Toxicology and Pharmacology of Organophosphorus Insecticide Self-Poisoning

Organophosphorus insecticide self-poisoning is a major global health problem, killing over 100,000 people annually. It is a complex multi-organ condition, involving the inhibition of cholinesterases, and perhaps other enzymes, and the effects of large doses of ingested solvents. Variability between organophosphorus insecticides—in lipophilicity, speed of activation, speed and potency of acetylcholinesterase inhibition, and in the chemical groups attached to the phosphorus—results in variable speed of poisoning onset, severity, clinical toxidrome, and case fatality. Current treatment is modestly effective, aiming only to reactivate acetylcholinesterase and counter the effects of excess acetylcholine at muscarinic receptors. Rapid titration of atropine during resuscitation is lifesaving and can be performed in the absence of oxygen. The role of oximes in therapy remains unclear. Novel antidotes have been tested in small trials, but the great variability in poisoning makes interpretation of such trials difficult. More effort is required to test treatments in adequately powered studies.

Psychiatric comorbidities in patients with intentional methanol intoxication

BACKGROUND

Intentional methanol intoxication (IMI) is an emerging public health issue in Asian countries, but few data are available in the literature on underlying psychiatric comorbidities in these suicide attempters.

PATIENTS AND METHODS

We conducted a retrospective chart review on patients with methanol intoxication (MI) treated at Chang-Gung Memorial Hospital, Linkou, Taiwan during 2000-2016. Of the 56 cases of documented MI, 16 were IMI. Baseline demographic, clinical, laboratory, psychiatric diagnoses, and mortality data were collected and analyzed.

RESULTS

Patient group with IMI had more females (62.5% vs 7.5%, P=0.000), less alcohol consumption (33.3% vs 92.5%, P=0.000), and less smoking (40.0% vs 79.5%, P=0.009), but higher past psychiatric disease (73.3% vs 10.0%, P=0.000) and past suicide attempts (81.1% vs 2.5%, P=0.000) than patient group with unintentional MI (UMI). Pesticides (50.0%) comprised the most common source used for suicide, followed by industrial methanol (37.5%). There was no significant difference in mortality rates between these two group (25.0% vs 22.5%, P=0.548). Twelve (75.0%) survivors of IMI were referred to a psychiatric consultation-liaison team, and depressive disorder (58.3%) and adjustment disorder (25.0%) were common.

CONCLUSION

There is a female predominance and a high prevalence of psychiatric comorbidities, namely depression and adjustment disorder in patients with IMI. Besides, alcohol consumption is a prevalent but not adequately treated condition in UMI group.

Study of Acid-Base Disorders and Biochemical Findings of Patients in a Tertiary Care Hospital: A Descriptive Cross-sectional Study

INTRODUCTION

Acid base disorder is a condition characterized by alteration in blood pH by the imbalance between the components of blood leading to a life threatening situation. The main aim of this study was to find the prevalence of acid-base disorders and biochemical findings of such disorders in patients in a tertairy care hospital.

METHODS

This descriptive cross-sectional study was conducted in Nobel Medical College Teaching Hospital from 1st September, 2018 to 31st August, 2019. Ethical apporoval was taken from Institutional Review Committee. All the patients presented to emergency department, intensive care units and wards were included during the study period. Data were entered and calculations were done in Microsoft Excel, point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data.

RESULTS

Out of arterial blood gas analysis of 1144 patients, the prevalence of acid base disorders was 718 (62.76%) at 95% Confidence Interval (59.96-65.56%). Simple and mixed acid base disorders were observed in 332 (46.24%) and 386 (53.76%) patients respectively. Respiratory alkalosis was most common among 134 (40.36%) cases in simple acid base disorder whereas metabolic acidosis and respiratory alkalosis was most common among 204 (52.85%) in mixed acid base disorder. All types of disorders were observed more in elderly people (41-60 and >60 age group) than other age groups.

CONCLUSIONS

Acid base disorder was found to be more common in very ill patients in emergency and intensive care units. Mixed acid base disorder was the most common with male and elderly patients in predominance.

Anion gap and base deficit are predictors of mortality in acute pesticide poisoning

BACKGROUND:

Acute pesticide poisoning has long been a serious problem as a method of suicide worldwide. This poisoning is a highly fatal condition that requires a rapid and precise diagnosis for adequate treatment. However, various studies on mortality predictor factors have been insufficient for whole pesticide treatments. We hypothesized that the initial plasma anion gap (AG) and base deficit (BD) are reliable prognostic factors.

METHODS:

A retrospective study analyzed 561 patients with a diagnosis of acute pesticide poisoning between January 1, 2014 and June 30, 2017. The initial AG and BD values were divided into quartiles according to the number of patients. Survival at 30 days from admission was estimated using the Kaplan-Meier survival analysis. Receiver-operator characteristic (ROC) curves were drawn, and the areas under the curve for AG and BD for mortality were calculated.

RESULTS:

Fifty-eight (10.3%) of 561 patients died within 30 days. The highest AG quartile (>22 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with an AG less than 14.7 mEq/L, these patients had a 4.18-fold higher risk of 30-day hospital mortality and the highest BD quartile (>7.9 mEq/L) was associated with an increased risk of 30-day hospital mortality. Compared to patients with a BD less than 1.4 mEq/L, these patients had 2.23-fold higher risk of 30-day hospital mortality. The areas under the ROC for AG and BD curve were 0.699 and 0.744, respectively.

CONCLUSIONS:

Initial high AG and BD values could predict mortality and require precise intensive care.

Rapid Diagnosis of Ethylene Glycol Poisoning by Urine Microscopy

Patient: Male, 57

Final Diagnosis: Ethylene glycol poisoning

Symptoms: Unconsciousness and high anion gap

Medication: Bicarbonate • electrolyte correction • intravenous ethyl alcohol infusion • hemodialysis

Clinical Procedure: icroscopy of calcium oxalate monohydrate crystals

Specialty: Nephrology • Intensive Care Unit • Biochemistry and Immunology

Pulmonary Infection Is an Independent Risk Factor for Long-Term Mortality and Quality of Life for Sepsis Patients

Background. Long-term outcomes (mortality and health-related quality of life) of sepsis have risen as important indicators for health care. Pulmonary infection and abdominal infection are the leading causes of sepsis. However, few researches about long-term outcomes focused on the origin of sepsis. Here we aim to study the clinical differences between pulmonary-sepsis and abdominal-sepsis and to investigate whether different infection foci were associated with long-term outcomes. Methods. Patients who survived after hospital discharge were followed up by telephone interview. Quality of life (QoL) was assessed using the EuroQol 5-dimension (EQ5D) questionnaire. Results. Four hundred and eighty-three sepsis patients were included, 272 (56.3%) had pulmonary-sepsis, and 180 (37.3%) had abdominal-sepsis. The overall ICU and one-year mortality rates of the cohort were 17.8% and 36.1%, respectively. Compared with abdominal-sepsis, pulmonary-sepsis patients had older age, higher APACHE II, higher ICU mortality (31.7% versus 12.6%), and one-year mortality (45.4% versus 24.4%), together with worse QoL. Age, septic shock, acute renal failure, fungus infection, anion gap, and pulmonary infection were predictors for one-year mortality and pulmonary infection was a risk factor for poor QoL. Conclusions. Pulmonary-sepsis showed worse outcome than abdominal-sepsis. Pulmonary infection is a risk factor for one-year mortality and QoL after sepsis.