Practice Trends in the Use of Extracorporeal Treatments for Poisoning in Four Countries

Toxidromes and a general approach to poisoning

A toxicologic syndrome, or toxidrome, is a distinct pattern of effects of poisoning. Well-defined toxidromes are the opioid, anticholinergic, cholinergic and sympathomimetic, and an additional described toxidrome is GABAergic. These toxidromes are named for the receptor effects causing their specific clinical findings, and knowledge of toxidromes allows rapid pattern recognition of specific poisonings. In this review, toxidromes and the initial assessment and general approach to management of acute poisoning are discussed. This article details the receptor-level effects of the poisoning, key clinical signs and symptoms and the role antidotes play in treatment. Clinical resources such as Toxbase and others exist to provide detailed guidance on clinical management of poisoning.

Neurologic Complications in Critically Ill Patients with Toxic Alcohol Poisoning: A Multicenter Population-Based Cohort Study

BACKGROUND

Toxic alcohol poisoning is regularly encountered in emergency departments and intensive care units (ICUs). Most patients present with an altered level of consciousness, but the subsequent course and spectrum of neurologic complications and outcomes is highly variable.

METHODS

We performed a population-based, multicenter retrospective cohort study of critically ill patients with toxic alcohol poisoning admitted to ICUs in Alberta, Canada, between 2007 and 2019 to describe neurologic sequelae, including seizures, coma, neuroimaging abnormalities, persistent cognitive or visual impairment, and mortality. Multivariate analysis was performed to identify predictors of poor outcome.

RESULTS

We identified 104 patients, including 55 (53%) with methanol ingestion, 36 (35%) with ethylene glycol ingestion, and 13 (13%) with isopropanol ingestion. In patients who underwent neuroimaging, abnormalities were detected in 9 of 24 (38%) with methanol toxicity, 5 of 20 (25%) with ethylene glycol toxicity, and 0 of 10 with isopropanol toxicity (p = 0.07). Basal ganglia were commonly involved with both methanol and ethylene glycol poisoning, but prominent subcortical involvement and restricted diffusion were observed only with methanol poisoning. The composite of death, persistent cognitive impairment, or visual loss occurred in 13 (24%) patients with methanol poisoning, compared with one (3%) with ethylene glycol poisoning and none with isopropanol poisoning (p = 0.006). Among patients with methanol toxicity, greater elevation of the anion gap and lower Glasgow Coma Scale score were independent predictors of poor outcome. No patient with an anion gap ≥ 28 at presentation had a favorable recovery. Progression to death by neurologic criteria occurred in 3 of 55 (5%) patients with methanol poisoning and in none with other toxic alcohols.

CONCLUSIONS

Methanol overdose is the most common form of toxic alcohol poisoning to result in ICU admission. Poor neurologic outcomes may occur especially with methanol poisoning, with more than one in five patients dying or having persistent cognitive or visual impairment. A wide anion gap independently predicts poor outcome, emphasizing the importance of expeditious recognition and treatment.

Management of Poisonings and Intoxications

Poisoning occurs after exposure to any of a number of substances, including medicines, which can result in severe toxicity including death. The nephrologist may be involved in poisonings that cause kidney disease and for targeted treatments. The overall approach to the poisoned patient involves the initial acute resuscitation and performing a risk assessment, whereby the exposure is considered in terms of the anticipated severity and in the context of the patient's status and treatments that may be required. Time-critical interventions such as gastrointestinal decontamination ( e.g. , activated charcoal) and antidotes are administered when indicated. The nephrologist is usually involved when elimination enhancement techniques are required, such as urine alkalinization or extracorporeal treatments. There is increasing data to guide decision making for the use of extracorporeal treatments in the poisoned patient. Principles to consider are clinical indications such as whether severe toxicity is present, anticipated, and/or will persist and whether the poison will be significantly removed by the extracorporeal treatment. Extracorporeal clearance is maximized for low-molecular weight drugs that are water soluble with minimal protein binding (<80%) and low endogenous clearance and volume of distribution. The dosage of some antidotes ( e.g. , N-acetylcysteine, ethanol, fomepizole) should be increased to maintain therapeutic concentrations once the extracorporeal treatment is initiated. To maximize the effect of an extracorporeal treatment, blood and effluent flows should be optimized, the filter with the largest surface area selected, and duration tailored to remove enough poison to reduce toxicity. Intermittent hemodialysis is recommended in most cases when an extracorporeal treatment is required because it is the most efficient, and continuous kidney replacement therapy is prescribed in some circumstances, particularly if intermittent hemodialysis is not readily available.

Derivation and elimination of uremic toxins from kidney-gut axis

Uremic toxins are chemicals, organic or inorganic, that accumulate in the body fluids of individuals with acute or chronic kidney disease and impaired renal function. More than 130 uremic solutions are included in the most comprehensive reviews to date by the European Uremic Toxins Work Group, and novel investigations are ongoing to increase this number. Although approaches to remove uremic toxins have emerged, recalcitrant toxins that injure the human body remain a difficult problem. Herein, we review the derivation and elimination of uremic toxins, outline kidney-gut axis function and relative toxin removal methods, and elucidate promising approaches to effectively remove toxins.

Kidney outcomes after methanol and ethylene glycol poisoning: a systematic review and meta-analysis

INTRODUCTION

Ingestions with methanol, ethylene glycol, diethylene glycol, propylene glycol, and isopropanol are rare yet exceedingly dangerous conditions that may require emergent management with kidney replacement therapy. Little is known regarding short- and long-term kidney outcomes post-ingestion.

OBJECTIVES

To comprehensively synthesize existing evidence regarding short- and long-term kidney and other outcomes of adult patients following these poisonings.

METHODS

We developed a search strategy in MEDLINE via OVID and then translated it into other databases including EMBASE (via OVID), PubMed, CENTRAL (via OVID). The databases were searched from their dates of inception to 29 July 2021. A grey literature search was conducted in the International Traditional Medicine Clinical Trial Registry and ClinicalTrials.gov. All interventional and observational studies and case series with ≥ five participants that reported on the outcomes of toxic alcohol (methanol, ethylene glycol, diethylene glycol, propylene glycol and isopropanol) poisonings in adult patients ≥18 years old were included. Studies that reported mortality, kidney outcomes and/or complications attributed to toxic alcohol poisoning were eligible.

RESULTS

The search strategy identified 1,221 citations. Sixty-seven studies (13 retrospective observational studies, one prospective observational study, 53 case series) met inclusion criteria (total N = 2,327 participants). No randomized controlled trials were identified per our prespecified criteria. Generally, included studies had small sample sizes (median of 27 participants) and were of low quality. Methanol and/or ethylene glycol poisoning made up 94.1% of included studies, whereas one study reported on isopropanol and none reported on propylene glycol. Results of the 13 observational studies of methanol and/or ethylene glycol poisoning were pooled for meta-analyses. The pooled in-hospital mortality estimates amongst patients with methanol and ethylene glycol poisoning were 24 and 11%, respectively. A more recent year of publication, female sex and mean age were associated with lower in-hospital mortality amongst individuals with ethylene glycol poisoning. Although hemodialysis was the most frequently employed kidney replacement therapy, the indications for initiation of this therapy were not reported in the majority of studies. At hospital discharge, kidney recovery occurred in 64.7-96.3% of patients with ethylene glycol poisoning. In studies of methanol and/or ethylene glycol poisoning, 2-3.7% of individuals required ongoing dialysis. Only one study reported post-discharge mortality. Furthermore, long-term toxic alcohol-mediated sequelae, such as visual and neurologic outcomes, were scarcely reported.

DISCUSSION

Ingestions of methanol and ethylene glycol were associated with a significant short-term risk of mortality. Although a wealth of literature in the form of case reports and case series exists, high-quality evidence regarding kidney outcomes after these poisonings is lacking. We identified a paucity of standardized reporting in clinical presentations, therapeutics and outcomes amongst adults with toxic alcohol poisoning. Amongst the included studies, there was substantial heterogeneity encompassing study type, outcomes, duration of follow-up and treatment modalities. These sources of heterogeneity restricted our ability to perform comprehensive meta-analyses of all outcomes of interest. An additional limitation is the lack of studies pertaining to propylene glycol and the paucity of data on isopropanol.

CONCLUSIONS

The indications for hemodialysis, long-term kidney recovery and long-term mortality risk vary widely in these poisonings and are inconsistently reported in the literature. This highlights the need for further research with standardized reporting of baseline kidney function, indications for initiation of kidney replacement therapy and short-term and long-term kidney outcomes.

REGISTRATION

This systematic review protocol is registered at PROSPERO, CRD42018101955.

Extracorporeal treatment for ethylene glycol poisoning: systematic review and recommendations from the EXTRIP workgroup

Ethylene glycol (EG) is metabolized into glycolate and oxalate and may cause metabolic acidemia, neurotoxicity, acute kidney injury (AKI), and death. Historically, treatment of EG toxicity included supportive care, correction of acid-base disturbances and antidotes (ethanol or fomepizole), and extracorporeal treatments (ECTRs), such as hemodialysis. With the wider availability of fomepizole, the indications for ECTRs in EG poisoning are debated. We conducted systematic reviews of the literature following published EXTRIP methods to determine the utility of ECTRs in the management of EG toxicity. The quality of the evidence and the strength of recommendations, either strong ("we recommend") or weak/conditional ("we suggest"), were graded according to the GRADE approach. A total of 226 articles met inclusion criteria. EG was assessed as dialyzable by intermittent hemodialysis (level of evidence = B) as was glycolate (Level of evidence = C). Clinical data were available for analysis on 446 patients, in whom overall mortality was 18.7%. In the subgroup of patients with a glycolate concentration ≤ 12 mmol/L (or anion gap ≤ 28 mmol/L), mortality was 3.6%; in this subgroup, outcomes in patients receiving ECTR were not better than in those who did not receive ECTR. The EXTRIP workgroup made the following recommendations for the use of ECTR in addition to supportive care over supportive care alone in the management of EG poisoning (very low quality of evidence for all recommendations): i) Suggest ECTR if fomepizole is used and EG concentration > 50 mmol/L OR osmol gap > 50; or ii) Recommend ECTR if ethanol is used and EG concentration > 50 mmol/L OR osmol gap > 50; or iii) Recommend ECTR if glycolate concentration is > 12 mmol/L or anion gap > 27 mmol/L; or iv) Suggest ECTR if glycolate concentration 8-12 mmol/L or anion gap 23-27 mmol/L; or v) Recommend ECTR if there are severe clinical features (coma, seizures, or AKI). In most settings, the workgroup recommends using intermittent hemodialysis over other ECTRs. If intermittent hemodialysis is not available, CKRT is recommended over other types of ECTR. Cessation of ECTR is recommended once the anion gap is < 18 mmol/L or suggested if EG concentration is < 4 mmol/L. The dosage of antidotes (fomepizole or ethanol) needs to be adjusted during ECTR.

The serum glycolate concentration: its prognostic value and its correlation to surrogate markers in ethylene glycol exposures

CONTEXT

Ethylene glycol poisoning manifests as metabolic acidemia, acute kidney injury and death. The diagnosis and treatment depend on history and biochemical tests. Glycolate is a key toxic metabolite that impacts prognosis, but assay results are not widely available in a clinically useful timeframe. We quantitated the impact of serum glycolate concentration for prognostication and evaluated whether more readily available biochemical tests are acceptable surrogates for the glycolate concentration.

OBJECTIVES

The objectives of this study are to 1) assess the prognostic value of the initial glycolate concentration on the occurrence of AKI or mortality in patients with ethylene glycol exposure (prognostic study); 2) identify surrogate markers that correlate best with glycolate concentrations (surrogate study).

METHODS

A systematic review of the literature was performed using Medline/PubMed, EMBASE, Cochrane library, conference proceedings and reference lists. Human studies reporting measured glycolate concentrations were eligible. Glycolate concentrations were related to categorical clinical outcomes (acute kidney injury, mortality), and correlated with continuous surrogate biochemical measurements (anion gap, base excess, bicarbonate concentration and pH). Receiver operating characteristic curves were constructed to calculate the positive predictive values and the negative predictive values of the threshold glycolate concentrations that predict acute kidney injury and mortality. Further, glycolate concentrations corresponding to 100% negative predictive value for mortality and 95% negative predictive value for acute kidney injury were determined.

RESULTS

Of 1,531 articles identified, 655 were potentially eligible and 32 were included, reflecting 137 cases from 133 patients for the prognostic study and 154 cases from 150 patients for the surrogate study. The median glycolate concentration was 11.2 mmol/L (85.1 mg/dL, range 0-38.0 mmol/L, 0-288.8 mg/dL), 93% of patients were treated with antidotes, 80% received extracorporeal treatments, 49% developed acute kidney injury and 13% died. The glycolate concentration best predicting acute kidney injury was 12.9 mmol/L (98.0 mg/dL, sensitivity 78.5%, specificity 88.1%, positive predictive value 86.4%, negative predictive value 80.9%). The glycolate concentration threshold for a 95% negative predictive value for acute kidney injury was 6.6 mmol/L (50.2 mg/dL, sensitivity 96.9%, specificity 62.7%). The glycolate concentration best predicting mortality was 19.6 mmol/L (149.0 mg/dL, sensitivity 61.1%, specificity 81.4%, positive predictive value 33.3%, negative predictive value 93.2%). The glycolate concentration threshold for a 100% negative predictive value for mortality was 8.3 mmol/L (63.1 mg/dL, sensitivity 100.0%, specificity 35.6%). The glycolate concentration correlated best with the anion gap (R² = 0.73), followed by bicarbonate (R² = 0.57), pH (R² = 0.50) and then base excess (R² = 0.25), while there was no correlation between the glycolate and ethylene glycol concentration (R² = 0.00). These data can assist clinicians in planning treatments such as extracorporeal treatments and prognostication. Potentially, they may also provide some reassurance regarding when extracorporeal treatments can be delayed while awaiting the results of further testing in patients in whom ethylene glycol poisoning is suspected but not yet confirmed.

CONCLUSIONS

This systematic review demonstrates that the glycolate concentration predicts mortality (unlikely if <8 mmol/L [61 mg/dL]). The anion gap is a reasonable surrogate measurement for glycolate concentration in the context of ethylene glycol poisoning. The findings are mainly based on published retrospective data which have various limitations. Further prospective validation studies are of interest.

Treating ethylene glycol poisoning with alcohol dehydrogenase inhibition, but without extracorporeal treatments: a systematic review

CONTEXT

Ethylene glycol is metabolized to toxic metabolites that cause acute kidney injury, metabolic acidemia, and death. The treatment of patients with ethylene glycol poisoning includes competitively inhibiting alcohol dehydrogenase with ethanol or fomepizole to prevent the formation of toxic metabolites, and extracorporeal treatments such as hemodialysis to remove ethylene glycol and its metabolites. In the absence of significant metabolic acidemia or kidney injury, it is hypothesized that extracorporeal treatments may be obviated without adverse outcomes to the patient if alcohol dehydrogenase inhibitors are used.

OBJECTIVES

The objectives of this study are to: (1) identify indicators predicting ADH inhibitor failure in patients with ethylene glycol poisoning treated with either ethanol or fomepizole for whom extracorporeal treatment was not performed (aside from rescue therapy, see below) (prognostic study), and (2) validate if the anion gap, shown in a previous study to be the best surrogate for the glycolate concentration, is associated with acute kidney injury and mortality (anion gap study).

METHODS

We conducted a systematic review to identify all reported patients with ethylene glycol poisoning treated without extracorporeal treatments but with either fomepizole (fomepizole monotherapy) or ethanol (ethanol monotherapy). Analyses were performed using both one case per patient and all cases (if multiple events were reported for a single patient). Data were compiled regarding poisoning, biochemistry, and outcomes. Treatment failure was defined as mortality, worsening of acid-base status, extracorporeal treatments used as rescue, or a worsening of kidney or neurological function after alcohol dehydrogenase inhibition was initiated. Also, we performed an analysis of previously described anion gap thresholds to determine if they were associated with outcomes such as acute kidney injury and mortality.

RESULTS

Of 115 publications identified, 96 contained case-level data. A total of 180 cases were identified with ethanol monotherapy, and 231 with fomepizole monotherapy. Therapy failure was noted mostly when marked acidemia and/or acute kidney injury were present prior to therapy, although there were cases of failed ethanol monotherapy with minimal acidemia (suggesting that ethanol dosing and/or monitoring may not have been optimal). Ethylene glycol dose and ethylene glycol concentration were predictive of monotherapy failure for ethanol, but not for fomepizole. In the anion gap study (207 cases), death and progression of acute kidney injury were almost nonexistent when the anion gap was less than 24 mmol/L and mostly observed when the anion gap was greater than 28 mmol/L.

CONCLUSION

This review suggests that in patients with minimal metabolic acidemia (anion gap <28 mmol/L), fomepizole monotherapy without extracorporeal treatments is safe and effective regardless of the ethylene glycol concentration. Treatment failures were observed with ethanol monotherapy which may relate to transient subtherapeutic ethanol concentrations or very high ethylene glycol concentrations. The results are limited by the retrospective nature of the case reports and series reviewed in this study and require prospective validation.

Prognostic factors of acetaminophen exposure in the United States: An analysis of 39,000 patients

Acetaminophen is a frequently used over-the-counter or prescribed medication in the United States. Exposure to acetaminophen can lead to acute liver cytolysis, acute liver failure, acute kidney injury, encephalopathy, and coagulopathy. This retrospective cohort study (1/1/2012 to 12/31/2017) investigated the clinical outcomes of intentional and unintentional acetaminophen exposure using the National Poison Data System data. The frequency of outcomes, chronicity, gender, route of exposure, the reasons for exposure, and treatments as described. Binary logistic regression was used to estimate the prognostic factors and odds ratios (OR) with 95% confidence intervals (CI) for outcomes. This study included 39,022 patients with acetaminophen exposure. Our study demonstrated that the likelihood of developing severe outcomes increased by aging (OR = 1.12, 95% CI: 1.08-1.015) and was lower in females (OR = 0.88, 95% CI: 0.78-0.99). Drowsiness/lethargy (OR = 1.48, 95% CI: 1.22-1.82), agitation (OR = 1.66, 95% CI: 1.11-2.50), coma (OR = 23.95, 95% CI: 17.05-33.64), bradycardia (OR = 2.29, 95% CI: 1.22-4.32), rhabdomyolysis (OR = 8.84, 95% CI: 3.71-21.03), hypothermia (OR = 4.1, 95% CI: 1.77-9.51), and hyperthermia 2.10 (OR = 2.10, 95% CI: 1.04-4.22) were likely associated with major outcomes or death. Treatments included intravenous N-acetylcysteine (61%), oral N-acetylcysteine (10%), vasopressor (1%), hemodialysis (0.7%), fomepizole (0.1%), hemoperfusion (0.03%), and liver transplant (0.1%). In conclusion, it is important to consider clinical presentations of patients with acetaminophen toxicity that result in major outcomes and mortality to treat them effectively.

Fundaments of Toxicology-Approach to the Poisoned Patient

Management of the poisoned patient begins with supportive care, assessment of organ function and dysfunction, and consideration of known or suspected poisons. The possibility of multiple ingestions should be considered with intentional exposures or suicide attempts. Enteric decontamination involves treatment to prevent the absorption of toxins from the gastrointestinal system and includes the use of activated charcoal. Poisoned patients may benefit from the use if antidotes are available, or enhanced elimination as with salicylate ion trapping during urinary alkalinization. The use of intravenous lipid therapy is of clinical benefit in poisoning from bupivacaine, amitriptyline, and bupropion. Hemodialysis is the most inexpensive, widely available, and most commonly used method of extracorporeal drug removal in the treatment of poisoning. Chelators with different chemical properties can bind toxic metals, providing an essential mechanism for detoxification, and may be used in combination with extracorporeal therapies such as DFO with HD for aluminum or iron, and DMSA or DMPS with HD to treat arsenic or mercury intoxication. The use of displacers with hemodialysis can be considered to augment clearance of protein-bound toxins.

Acute Renal Failure of Nosocomial Origin

BACKGROUND

10-20% of hospitalized patients develop acute kidney injury (AKI)/acute renal failure during their hospital stay. The mortality of nosocomial AKI is approximately 30%.

METHODS

This review is based on relevant publications retrieved by a search in multiple databases (PubMed and Uptodate), archives, and pertinent medical journals.

RESULTS

The most common causes of nosocomial AKI are volume depletion, sepsis, heart diseases, polytrauma, liver diseases, and drug toxicity. AKI can also be of postrenal (obstructive) origin, or a result of renal diseases including glomeruloneph- ritis, vasculitis, tubulointerstitial nephritis, and cholesterol embolism. In about 13% of cases, nosocomial AKI develops on the basis of pre-existing chronic renal disease. Patients with AKI are at elevated risk of developing chronic renal disease and must be followed up appropriately after they are discharged from the hospital. Indispens- able elements of the evaluation of nosocomial AKI include renal ultrasonography, the exclusion of postrenal obstruction, urine chemistry, and microbiological urinaly- sis. Potentially nephrotoxic drugs and those that impair renal hemodynamics must be avoided to the greatest possible extent in patients with acute renal damage. Hypotension must be avoided as well.

CONCLUSION

Early, specific nephrological diagnosis and treatment are important components of the management of nosocomial AKI, particularly because causally directed treatment is available for some of the conditions that underlie it.

Extracorporeal Removal of Poisons and Toxins

Extracorporeal therapies have been used to remove toxins from the body for over 50 years and have a greater role than ever before in the treatment of poisonings. Improvements in technology have resulted in increased efficacy of removing drugs and other toxins with hemodialysis, and newer extracorporeal therapy modalities have expanded the role of extracorporeal supportive care of poisoned patients. However, despite these changes, for at least the past three decades the most frequently dialyzed poisons remain salicylates, toxic alcohols, and lithium; in addition, the extracorporeal treatment of choice for therapeutic removal of nearly all poisonings remains intermittent hemodialysis. For the clinician, consideration of extracorporeal therapy in the treatment of a poisoning depends upon the characteristics of toxins amenable to extracorporeal removal (e.g., molecular mass, volume of distribution, protein binding), choice of extracorporeal treatment modality for a given poisoning, and when the benefit of the procedure justifies additive risk. Given the relative rarity of poisonings treated with extracorporeal therapies, the level of evidence for extracorporeal treatment of poisoning is not robust; however, extracorporeal treatment of a number of individual toxins have been systematically reviewed within the current decade by the Extracorporeal Treatment in Poisoning workgroup, which has published treatment recommendations with an improved evidence base. Some of these recommendations are discussed, as well as management of a small number of relevant poisonings where extracorporeal therapy use may be considered.

[Acute intoxications: markers for screening, diagnosis and therapy monitoring]

Acute poisonings account for a significant proportion of the patient population presenting to intensive care units, whereby mixed drug overdoses and prescription drug overdoses predominate. The aim of this article was to describe indications for screening, diagnosis and therapy monitoring in acute overdoses in the intensive care unit. To conduct this work, a literature search was carried out and a review was written based on guidelines, case reports, expert opinions and scientific publications. Toxidromes are a useful tool for classification of clinical characteristics when the causative agent is initially unknown. Especially in critical care medicine, identifying and quantifying of the causative toxin by enzyme immunoassays, chromatography and mass spectrometry should be attempted. Intensive care treatment of patients with acute overdoses includes not only monitoring and support of vital functions but also methods for primary and secondary elimination of toxins. The indication for the use of extracorporeal procedures should be carefully evaluated and the method should be chosen based on protein binding and molecular size. Lipid emulsion therapy, high-dose insulin euglycaemia therapy and hyperbaric oxygenation are also increasingly used.

Extracorporeal Treatment in the Management of Acute Poisoning: What an Intensivist Should Know?

Extracorporeal treatment (ECTR) represents a treatment modality promoting removal of endogenous or exogenous poisons and supporting or temporarily replacing a vital organ. This article aims to provide a brief overview of the technical aspects and the potential indications and limitations of the different ECTRs, highlighting the important characteristics of poison amenable to ECTR and the most appropriate prescriptions used in the setting of acute poisoning. The various principles that govern poison elimination by ECTR (diffusion, convection, adsorption, and centrifugation) and how components of the ECTR can be adjusted to maximize clearance have also being discussed.

Outcomes after toxic alcohol poisoning: a systematic review protocol

BACKGROUND

Toxic alcohols have been implicated in accidental ingestions and intentional exposures. Recognition of toxic alcohol poisoning is challenging. The main treatment modalities include antidotes with alcohol dehydrogenase inhibitors and dialysis. Current guidelines exist for both methanol and ethylene glycol intoxication. However, treatment consensus related to other toxic alcohols is limited. Furthermore, uncertainties regarding thresholds for when to initiate antidotes and dialysis persist. As a consequence, variations exist in the interventions utilized for management of all toxic alcohol poisonings. To our knowledge, no prior systematic review of clinical outcomes of toxic alcohols exists. The objective of this study is to summarize existing evidence on short- and long-term outcomes of patients following toxic alcohol poisonings, including methanol, ethylene glycol, isopropanol, propylene glycol, and diethylene glycol.

METHODS

A literature search in PubMed, MEDLINE, and EMBASE will be performed based on pre-determined criteria. There will be no restrictions on publication dates or languages. The search will be supplemented by manual scan of bibliographies of eligible studies and gray literature assessment. Observational studies and clinical trials will be included in this review. Once eligible studies have been selected based on pre-specified criteria, two investigators will extract relevant data independently and perform quality assessment per validated tools. A pooled analysis of mortality and short- and long-term secondary outcomes will be performed. Pre-specified subgroup analyses will be performed according to the type of toxic alcohol intoxication, mode of renal replacement therapy, and medical interventions received. A meta-analysis will be performed if three or more studies with similar populations, type of toxic alcohol poisoning, and outcome measures, as well as adequate quality, are identified. This review will be reported according to the recommendations of the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) Statement.

DISCUSSION

This systematic review aims to synthesize current evidence in the short- and long-term outcomes of post-toxic alcohol poisoning. The results will enhance the understanding of patient morbidity and mortality after toxic alcohol poisoning, help inform uniform concrete management guideline development, identify gaps in the current state of knowledge, and provide evidence to help implement post-treatment follow-up.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42018101955.

Extracorporeal treatments in poisonings from four non-traditionally dialysed toxins (acetaminophen, digoxin, opioids and tricyclic antidepressants): A combined single-centre and national study

The use of extracorporeal treatments (ECTRs) for poisonings with four non-traditionally dialysed toxins (NTDTs) is increasing in the United States. This study evaluated whether ECTRs are prescribed for toxin removal or the treatment of other medical illnesses or complications. We performed a 2-Phase retrospective analysis evaluating the main indication for ECTRs in patients with poisoning from a NTDT (defined for this study as acetaminophen, opioids, tricyclic antidepressants (TCAs) or digoxin) and ECTR. The first phase assessed all cases from a single site (New York City Poison Control Center) between the years 2000 and 2016, and the second phase surveyed all United States Poison Control Centers (PCCs). In Phase 1, demographics, toxin ingested and main indication for ECTR were extracted. In Phase 2, a query to the National Poison Data System using the a pragmatic subset of inclusion criteria from Phase 1 restricted to single toxin ingestions over a narrower time frame (2014-2016) provided the cases for study. A structured online questionnaire was sent to all United States PCCs to request their database review regarding the indication for ECTR for their cases. In Phase 1, 92 cases met inclusion criteria. In Phase 2, 519 cases were screened and 425 met inclusion criteria. In Phase 1 91/92 (98.9%) and Phase 2 411/425 (96.7%), of extracorporeal treatments were used to treat underlying medical conditions or poisoning-related complications rather than accelerate toxin removal. The increasing number of ECTRs reported in patients who ingested one of the four NTDTs thus appears to be for medical indications rather than attempts at toxin removal, a distinction that is important.

Recent advances in green nanoparticulate systems for drug delivery: efficient delivery and safety concern

Nanotechnology manipulates therapeutic agents at the nanoscale for the development of nanomedicines. However, there are current concerns over nanomedicines, mainly related to the possible toxicity of nanomaterials used for health medications. Due to their small size, they can enter the human body more readily than larger sized particles. Green chemistry encompasses the green synthesis of drug-loaded nanoparticles by reducing the use of hazardous materials in the synthesis process, thus reducing the adverse health impacts of pharmaceutics. This would greatly expand their potential in biomedical treatments. This review highlights the potential risks of nanomedicine formulations to health, delivery routes of green nanomedicines, recent advances in the development of green nanoscale systems for biomedical applications and future perspectives for the green development of nanomedicines.