Evaluation of capillary miR-122 as a prognostic biomarker of paracetamol-induced liver toxicity.

INTRODUCTION: Paracetamol (acetaminophen) overdose is a leading cause of acute liver failure in many Western countries. Diagnostic tools for this poisoning may be suboptimal in some cases and new biomarkers have been investigated. We investigated the role of capillary microRNA-122 (miR-122) as a prognostic biomarker of liver injury in the clinical management of patients with paracetamol overdose. METHODS: In a paracetamol overdose patient cohort, miR-122 was measured by quantitative polymerase chain reaction in a blood drop obtained by a finger prick at the end of an antidote cycle treatment with N-acetylcysteine treatment (12 h). Liver injury was defined as serum alanine aminotransferase (ALT) activity > 100 IU/L collected at 10 or 20 h after the start of treatment. Pearson's correlation analyses were performed. RESULTS: In patients with paracetamol overdose, capillary miR-122 was positively correlated with ALT measured at 10 h and at 20 h (r = 0.83, P < 0.0001; r = 0.96, P < 0.0001, respectively). CONCLUSION: This work supports the potential use of capillary miR-122 as a prognostic biomarker of liver injury throughout clinical management of patients with paracetamol overdose. Capillary miR-122 can be measured in a blood drop collected by a finger prick, a minimally invasive diagnostic test for patient stratification.

New drug controls and reduced hospital presentations due to novel psychoactive substances in Edinburgh.

AIMS: Recreational use of novel psychoactive substance (NPS) has become increasingly common. We aimed to assess the association of national legislation and local trading standards activity with hospital presentations. METHODS: We established observational cohorts of patients with recreational drug toxicity presenting to Edinburgh Royal Infirmary and dying with detectable recreational drugs in Edinburgh. We assessed associations with two temporary class drug-orders (April 2015: methylphenidates, Nov 2015: methiopropamine), the Psychoactive Substances Act (June 2016), and trading standards forfeiture orders (October 2015). RESULTS: The methylphenidate temporary class drug-order was associated with rapid 46.7% (P = 0.002) and 21.0% (P = 0.003) reductions in presentations and admissions, respectively, for NPS drug toxicity, comparing 12 months before with 6 months after. The change was greatest for ethylphenidate toxicity (96.7% reduction in admissions, P < 0.001) that was partly offset by a tripling in synthetic cannabinoid receptor agonist cases (P < 0.001) over the next 6 months. This increase reversed following trading standards activity removing all NPS drugs from local shops in October 2015, associated with 64.3% (P < 0.001) and 83.7% (P < 0.001) reductions in presentations and admissions, respectively, for all NPS drugs over the next 12 months. The effect was sustained and associated with a reduced postmortem detection of stimulant NPS drugs. The two interventions prevented an estimated 557 (95% confidence interval 327-934) NPS admissions during 2016, saving an estimated £303 030 (£177 901-508 133) in hospital costs. CONCLUSIONS: We show here that drug legislation and trading standards activity may be associated with effective and sustained prevention. Widespread adoption of trading standards enforcement, together with focused legislation, may turn the tide against these highly-damaging drugs.

Effect of the UK's revised paracetamol poisoning management guidelines on admissions, adverse reactions and costs of treatment.

AIMS: In September 2012 the UK's Commission on Human Medicines (CHM) recommended changes in the management of paracetamol poisoning: use of a single '100 mg l(-1) ' nomogram treatment line, ceasing risk assessment, treating all staggered/uncertain ingestions and increasing the duration of the initial acetylcysteine (NAC) infusion from 15 to 60 min. We evaluated the effect of this on presentation, admission, treatment, adverse reactions and costs of paracetamol poisoning. METHODS: Data were prospectively collected from adult patients presenting to three large UK hospitals from 3 September 2011 to 3 September 2013 (year before and after change). Infusion duration effect on vomiting and anaphylactoid reactions was examined in one centre. A cost analysis from an NHS perspective was performed for 90 000 patients/annum with paracetamol overdose. RESULTS: There were increases in the numbers presenting to hospital (before 1703, after 1854; increase 8.9% [95% CI 1.9, 16.2], P = 0.011); admitted (1060/1703 [62.2%] vs. 1285/1854 [69.3%]; increase 7.1% [4.0, 10.2], P < 0.001) and proportion treated (626/1703 [36.8%] vs. 926/1854 [50.0%]; increase: 13.2% [95% CI 10.0, 16.4], P < 0.001). Increasing initial NAC infusion did not change the proportion of treated patients developing adverse reactions (15 min 87/323 [26.9%], 60 min 145/514 [28.2%]; increase: 1.3% [95% CI -4.9, 7.5], P = 0.682). Across the UK the estimated cost impact is £8.3 million (6.4 million-10.2 million) annually, with a cost-per-life saved of £17.4 million (13.4 million-21.5 million). CONCLUSIONS: The changes introduced by the CHM in September 2012 have increased the numbers of patients admitted to hospital and treated with acetylcysteine without reducing adverse reactions. A safety and cost-benefit review of the CHM guidance is warranted, including novel treatment protocols and biomarkers in the assessment of poisoning.

Assessment and management of paracetamol poisoning in adults.

Paracetamol is a low cost, effective analgesic that is widely available in the UK. Paracetamol is the drug most commonly taken in overdose and can lead to acute liver failure, which can be fatal. This article focuses on the assessment and management of paracetamol poisoning in adults. It includes current UK guidelines on paracetamol poisoning, which changed in September 2012 following a review by the Commission on Human Medicines. It also discusses strategies to reduce incidence and severity of paracetamol poisoning, and outlines the metabolism of paracetamol at therapeutic doses and in overdose.

Management of poisoning in adults.

Nurses play a key role in the care of patients presenting with poisoning. Assessment and management of such patients can be challenging, especially if they are intoxicated, have co-ingested other agents or their mental health is compromised. In addition, some nurses may be unfamiliar with current management guidelines. This article outlines a number of protocols and initiatives aimed at improving consistency in the management of patients following an overdose. The article focuses on paracetamol poisoning, the most common overdose presentation in the UK. This article was updated on May 7 2013 to include current UK guidelines for management of paracetamol overdose, which changed in September 2012 following a review by the Commission on Human Medicines. In addition, the authors published recently an article in this journal that discussed the assessment and management of patients who present to hospital following a paracetamol overdose ( Pettie and Dow 2013 ).

An integrated care pathway improves the management of paracetamol poisoning.

BACKGROUND: Paracetamol poisoning remains a major cause of morbidity and mortality. Clinical care of paracetamol poisoning depends on a range of patient variables and typically involves both medical and nursing care. An integrated care pathway (ICP) is a multidisciplinary management plan that incorporates guidelines and best practice to enhance care and documentation for a specific patient group. Paracetamol overdose is thus amenable to an ICP. AIM: To evaluate the introduction of an ICP on process of care of the paracetamol poisoned patient. METHODS: A retrospective case note review of consecutive patients admitted to the Royal Infirmary of Edinburgh following a paracetamol overdose was conducted. Data were collected for a 3-month period before and after introduction of the ICP to the emergency department and toxicology inpatient unit. RESULTS: The ICP was used in 77% of cases in the time period studied and was associated with improvements in initial documentation of patient assessment (pre-ICP vs post-ICP: 87/161 (54%) vs 101/113 (89%), p<0.0001) and appropriateness of blood sampling (146/161 (91%) vs 111/113 (98%), p=0.01), but no change in timely blood sampling (pre 124/161 (77%) vs post 93/113 (82%)). All aspects of intravenous acetylcysteine administration also significantly improved: administration of acetylcysteine if indicated (pre-ICP vs post-ICP: 57/71 (80%) vs 71/71 (100%), p<0.0001); acetylcysteine commenced in a timely fashion (33/71 (46%) vs 55/71 (77%), p=0.0002); and acetylcysteine correctly prescribed (44/58 (76%) vs 71/71 (100%), p<0.0001). CONCLUSIONS: Implementation of an ICP for paracetamol poisoning significantly improved patient management and helped to standardise inter-professional decision making in this challenging patient group. This is likely to improve patient outcome.

Safety and Efficacy of the SNAP 12-hour Acetylcysteine Regimen for the Treatment of Paracetamol Overdose.

BACKGROUND: Acetylcysteine (NAC) is effective at preventing liver injury after paracetamol overdose. The Scottish and Newcastle Anti-emetic Pre-treatment for Paracetamol Poisoning (SNAP) Study demonstrated that a 12 h NAC regimen was associated with fewer adverse drug reactions compared with the standard 21 h regimen. Here, we describe the clinical effectiveness of the SNAP NAC regimen. METHODS: The SNAP regimen, consisting of intravenous NAC 100 mg/kg over 2 h then 200 mg/kg over 10 h, was introduced to treat all paracetamol overdose patients at the Royal Infirmary of Edinburgh, the Royal Victoria Infirmary, Newcastle and St Thomas' Hospital, London. Patient data were prospectively and systematically collected before and after the change in treatment (total patients N = 3340, 21 h N = 1488, SNAP N = 1852). Health record linkage was used to determine patient outcome after hospital discharge. FINDINGS: There was no difference in liver injury or liver synthetic dysfunction between regimens. Hepatotoxicity (peak ALT > 1000 U/L) occurred in 64 (4.3%) and 67 (3.6%) patients, respectively, in the 21 h and SNAP groups (absolute difference - 0.7%, 95% CI - 2.1 to 0.6). Multivariable logistic regression did not identify treatment regimen as an outcome-associated factor. No patients were readmitted to hospital with, or died from, liver failure within 30 days of discharge. Anti-histamine treatment (for NAC anaphylactoid drug reactions) was prescribed for 163 (11.0%) patients with the 21 h regimen and 37 (2.0%) patients with the SNAP regimen (absolute difference 9.0% (95% CI 7.3 to 10.7)). INTERPRETATION: In clinical use the SNAP regimen has similar efficacy as standard therapy for preventing liver injury and produces fewer adverse reactions.

Lower incidence of anaphylactoid reactions to N-acetylcysteine in patients with high acetaminophen concentrations after overdose.

BACKGROUND: Mechanisms responsible for anaphylactoid reactions to N-acetylcysteine (NAC) are poorly understood, and acetaminophen itself may play an important role. The present study examined the relationship between serum acetaminophen concentrations and risk of anaphylactoid reactions. METHODS: Prospective study of adverse reactions to NAC administered according to standardized clinical protocols in patients who present to hospital after acute acetaminophen overdose. Subgroups were defined by serum acetaminophen concentrations 0 to 100 mg/L, 101 to 150 mg/L, 151 to 200 mg/L, 201 to 300 mg/L, and >300 mg/L. RESULTS: There were 362 patients, and anaphylactoid reactions occurred in 14.9%. Anaphylactoid reactions occurred less commonly in patients with high serum acetaminophen concentrations (p = 0.046 by Cochran-Armitage trend test) and high equivalent 4 h acetaminophen concentrations (p = 0.004). DISCUSSION: High serum acetaminophen concentrations were associated with fewer anaphylactoid reactions, suggesting that these might in some way be protective. The biological basis needs further exploration so as to allow a better understanding of the mechanisms responsible for adverse reactions to NAC treatment.