List I - Core Conditions Flashcards
What is the treatment for paracetamol overdose?
- Activated charcoal if ingested <1 hour
- N-acetylcysteine (NAC)
- Liver transplant if at serious risk
What is the treatment for salicylate (aspirin) overdose?
- Urinary alkalinization is now rarely used - contraindicated in cerebral and pulmonary oedema, most units proceed straight to haemodialysis in cases of severe poisoning
- Haemodialysis
What is the treatment for opiates/opioid overdose?
- Naloxone 0.4-2mg IV/IM
- Can repeat every 2 minutes until breathing is adequate
- Alternatively can give doxapram for respiratory depression
- Add Lomotil 2 tablets/6 hrs PO (combined diphenoxylate and atropine for cramps/diarrhoea from opiate withdrawal
- Methadone can be used for opiate withdrawal
- 10-30mg/12h PO if opiate withdrawal
What is the treatment for benzodiazepine overdose (lorazepam, diazepam, midazolam)?
- Flumenazil
- Most cases are managed with supportive care due to the risk of seizures with flumenazil - generally only used with severe or iatrogenic overdoses
What is the management of warfarin overdose?
- Vitamin K, prothrombin complex
What is the management of heparin overdose?
- Protamine sulphate
What is the management of Beta-blocker overdose?
- If the patient is bradycardic then atropine
* In resistant cases glucagon may be used
What is the management of ethylene glycol (anti-freeze) poisoning?
- Fomepizole - inhibitor of alcohol dehydrogenase is now used first line
- Ethanol was used previously as it competes for the enzyme alcohol dehydrogenase
- Limits the formation of toxic metabolites (e.g. glycoaldehyde and glycolic acid) responsible for the haemodynamic/metabolic features of poisoning
- Haemodialysis also has a role to play
What is the management of methanol (methyl alcohol) poisoning?
- Fomepizole or ethanol
* Haemodialysis
What is the management of organophosphate insecticide (phosphate ester) poisoning?
- Atropine
What is the management of digoxin poisoning?
- Digoxin-specific antibody fragments
What is the management of iron poisoning?
- Desferrioxamine - a chelating agent
What is the management of lead poisoning?
- Dimercaprol - calcium edetate
What is the management of carbon monoxide poisoning?
- 100% oxygen
* Hyperbaric oxygen
What is the management of cyanide poisoning?
- Hydroxocabalamin, also combination of amyl nitrite, sodium nitrite and sodium thiosulfate
What is the management of tricyclic antidepressant overdose?
- IV sodium bicarbonate may reduce the risk of seizures and arrhythmias in severe toxicity
- Correction of acidosis is the first line in the management of tricyclic induced arrhythmias
What is the management of lithium overdose/toxicity?
- Mild-moderate toxicity may respond to volume resuscitation with normal saline
- Haemodialysis may be needed in severe toxicity
- Sodium bicarbonate is sometimes used but there is limited evidence to support this- by increasing the alkalinity of the urine it promotes lithium excretion
What are the clinical features of aspirin (salicylate) overdose?
- Hyperventilation (centrally stimulates respiration)
- Tinnitus
- Lethargy
- Sweating, pyrexia
- Nausea/vomiting
- Hyperglycaemia and hypoglycaemia
- Seizures
- Coma
What are the principles of treatment for aspirin (salicylate) overdose?
- General ABC
- Urinary alkalinization with intravenous sodium bicarbonate - enhances elimination of aspirin in the urine
- Haemodialysis
What is the criteria for haemodialysis in salicylate overdose?
- Serum concentration of >700 mg/L
- Metabolic acidosis resistant to treatment
- Acute renal failure
- Pulmonary oedema
- Seizures
- Coma
What is the pathophysiology of salicylate overdose?
- Salicylates cause the uncoupling of oxidative phophorylation leading to decreased adenosine triphosphate production, increased oxygen consumption and an increased carbon dioxide and heat production
What is the blood gas picture for a patient with aspirin overdose?
- Leads to a mixed respiratory alkalosis and metabolic acidosis
- Raised anion gap
- Early stimulation of the respiratory centre leads to a respiratory alkalosis whilst later the direct acid effects of salicylates (combined with acute renal failure) may lead to an acidosis
- In children metabolic acidosis tends to predominate
What level is considered less severe in aspirin overdose?
- Plasma salicylate concentration of less than 500 mg/litre (3.6 mmol/litre) is considered less severe
How should urine excretion be managed in aspirin overdose?
- Fluid losses should be replaced and IV sodium bicarbonate may be given (ensuring plasma potassium concentration is within the reference range to enhance urinary salicylate excretion)
- Plasma potassium concentration should be corrected before giving sodium bicarbonate as hypokalaemia may complicate alkalinisation of the urine
What fluid regime should be given for alkalinisation of urine after salicylate OD?
- Correct dehydration/hypokalaemia (fluids, K+ supplements
- Take salicylate level after 2 hrs
- If level is >500mg/L (3.6mm/L) consider alkalinisation of urine
- Use 1.5 L 1.26% NaHCO with 40 mmol KCl IV over 3 hrs
- Aim to make the urine pH 7.5 - 8.5
- Monitor UO, blood glucose, U and E’s especially K+ as can reduce serum pH, ECG
- If >700mg/L consider dialysis or if renal HF, seizures, severe acidosis, persistently high levels
What is the current recommended level of alcohol for men and women in the UK?
- No more than 14 units per week
- If you do drink as much as 14 units per week it is best to spread this evenly over 3 days or more
- Pregnant women should not drink alcohol
What is one unit of alcohol equivalent to?
- 10 mL of pure ethanol
Examples include:
- 25ml single measure of spirits (ABV 40%)
- 1/3 of a pint of beer (ABV 5 to 6%)
- 1/2 a 175ml standard glass of red wine (ABV 12%)
How can you calculate the number of units of alcohol in a drink?
- Multiply the number of millilitres by the ABV and divide by 1000
- For example:
- 1/2 175ml standard glass of red wine = 87.5 * 12 / 1000 = 1.05 units
- 1 bottle of wine = 750 * 12 / 1000 = 9 units
- 1 pint of 5% beer or lager = 568 * 5 / 1000 = 2.8 units
What is the mechanism of acute alcohol withdrawal?
- Chronic alcohol consumption enhances GABA mediated inhibition in the CNS (similar to benzodiazepines) and inhibits NMDA-type glutamate receptors
- Alcohol withdrawal is thought to lead to decreased inhibitory GABA and increased NMDA glutamate transmission
How does acute alcohol withdrawal present?
- Symptoms start at 6-12 hours - tremor, sweating, tachycardia, anxiety
- Peak incidence of seizures is at 36 hours
- Peak incidence of delirium tremens is at 48-72 hours - course tremor, confusion, delusions, auditory and visual hallucinations, fever, tachycardia
What is the management of acute alcohol withdrawal?
- Patients with history of complex withdrawals from alcohol (i.e. delirium tremens, seizures, blackouts) should be admitted to hospital for monitoring until withdrawals stabilised
- First-line: benzodiazepines such as chlordiazepoxide (lorazepam may be preferable in patients with hepatic failure - typically given as part of a reducing dose protocol) or carbamazepine
- People with decompensated liver disease who are being treated for acute alcohol withdrawal should be offered advice from a health care professional experienced in this area
- Offer information about how to contact local alcohol support services - Forward Leeds
What can be used to quantify severity of alcohol withdrawal?
- Clinical Institute Withdrawal Assessment - Alcohol, revised scale is a validated 10-item assessment tool to quantify the severity of the alcohol withdrawal syndrome and to monitor and medicate patients throughout withdrawal
- Patients with scores < or equal to 8 typically do not require medication for withdrawal
For people being managed for acute alcohol withdrawal, what is the management for delirium tremens?
- Offer oral lorazepam first line
* Haloperidol second line
For people being managed for acute alcohol withdrawal, what is the management for withdrawal seizures?
- Consider offering a quick acting benzodiazepine such as lorazepam
(Do not offer phenytoin to treat alcohol withdrawal seizures)
What is Wernicke’s encephalopathy?
- Acute neurological condition characterised by a triad of ophthalmoparesis with nystagmus, ataxia, and confusion
- Life threatening illness caused by thiamine deficiency which primarily affects the peripheral and central nervous systems
What should patients in acute alcohol withdrawal be given to reduce the risk of them developing Wernicke’s encephalopathy?
- Offer B1 thiamine in high doses (Pabrinex)
* Should be given for a minimum of 5 days
Which patients should be offered prophylactic thiamine (B1)?
- Harmful (35 units or more for men or 50 units or more for women) or dependent drinkers if they are:
- Malnourished
- Have decompensated liver disease
- Are in acute withdrawal
- Before and during a planned medically assisted alcohol withdrawal
What can be used to formally assess a person who is drinking alcohol to excess to identify the nature and severity of their alcohol misuse?
- AUDIT or AUDIT-C (Alcohol Use Disorders Identification Test)
- Can help to identify whether a brief intervention is required or not and if so what type (AUDIT-C is an abbreviated version
- Low-risk drinking score 1-7
- Hazardous drinking score 8-15
- Harmful drinking score 16-19
- Possible alcohol dependence score of 20 or more
** If the AUDIT score suggests alcohol dependence, consider assessing its severity using the SADQ (Severity of Alcohol Dependence Questionnaire) or LDQ (Leeds Dependence Questionnaire)
Cut-offs for the SADQ are:
- Mild — 15 or less
- Moderate — 15–30
- Severe — 31 or more.
Cut-offs for the LDQ are:
- Low dependence — less than 10
- Medium dependence — 10–22
- High dependence —over 22
What brief advice can be given to a person who is drinking hazardous or harmful amounts of alcohol?
- FRAMES principles
- Feedback - on the persons risk of having alcohol problems
- Responsibility - change is the person’s responsibility
- Advice - provision of clear advice when requested
- Menu - what are the options for change
- Empathy - an approach that is warm, reflective and understanding
- Self-efficacy - optimism about the person’s ability to change their own behaviour
What are the possible psychological interventions people with alcohol problems may benefit from?
- CBT and behavioural therapies - one 60 minute session per week for 12 weeks
- Social network and environment based therapies - focused of alcohol related problems should usually consist of 8 x 50 minute sessions over 12 weeks
- Behavioural couples therapy - focused on alcohol related problems and their effect on the person’s relationships - should usually consist of one 60 minute session per week for 12 weeks
What are the main points regarding smoking cessation from NICE guidance?
- Patients should be offered nicotine replacement therapy, varenicline or bupriopion - clinicians should not favour one over another
- This should normally be prescribed as part of a commitment to stop smoking on or before a particular date (target stop date)
- Prescription should last only until 2 weeks after the target date to stop - normally this will be after 2 weeks of NRT and 3-4 weeks for varenicline and bupropion to allow for different methods of administration and mode of action
- In unsuccessful do not offer a repeat prescription with 6 months unless special circumstances have intervened
- Do not offer NRT, varenicline or bupropion in any combination
What is varenicline?
- A nicotinic receptor partial agonist
How should varenicline be administered?
- Should be started 1 week before the patients target date to stop
- Recommended course of treatment is 12 weeks but patients should be monitored regularly and treatment only continued if not smoking
- Has been shown in studies to be more effective than bupropion
- Nausea is the most common adverse side effect, other common problems include headache, insomnia, abnormal dreams
- Varenicline should be used with caution in patients with a history of depression or self harm
- Contra-indicated in pregnancy and breast feeding
What is bupropion?
- A norepinephrine and dopamine reuptake inhibitor and nicotinic antagonist
How should bupropion be administered?
- Should be started 1 to 2 weeks before patients target date to stop
- Small risk of seizures 1/1000
- Contraindicated in epilepsy, pregnancy and breast feeding
- Having an eating disorder is a relative contraindication
How should pregnant women be management in terms of smoking cessation?
- NICE guidance recommends that all pregnant women should be tested for smoking using carbon monoxide detectors - some women find it difficult to say that they smoke because the pressure not to smoke in pregnancy is so intense
- All women who smoke or have stopped smoking within the last 2 weeks or those with a CO reading of 7 ppm or above should be referred to NHS Stop Smoking Services
What interventions can be used for pregnant women who want to stop smoking?
- First line in pregnancy should be CBT, motivational interviewing or structured self help and support from NHS Stop Smoking Services
- NRT if the above measures fail
- Varenicline and Bupropion are contraindicated in pregnancy
What is the mechanism of action of cocaine?
- Cocaine blocks the uptake of dopamine, noradrenaline and serotonin
What are the cardiovascular adverse effects of cocaine toxicity?
- Myocardial infarction
- Both tachycardia and bradycardia may occur
- Hypertension
- QRS widening and QT prolongation
- Aortic dissection
What are the neurological adverse effects of cocaine toxicity?
- Seizures
- Mydriasis
- Hypertonia
- Hyper-reflexia
What are the psychiatric adverse effects of cocaine toxicity?
- Agitation
- Psychosis
- Hallucinations
What other systemic complications can cocaine toxicity lead to?
- Ischaemic colitis - should be considered in patients complaining of abdominal pain or rectal bleeding
- Hyperthermia
- Metabolic acidosis
- Rhabdomyolysis
How should cocaine toxicity be managed?
- In general benzodiazepines are first line for most cocaine related problems
- Chest pain - benzodiazepines + glyceryl trinitrate - if MI develops then PCI
- Hypertension - benzodiazepines + sodium nitroprusside + beta blockers
What is ecstasy?
- MDMA 3,4 Methylenedioxymethamphetamine
What are the clinical features of ecstasy toxicity?
- Neurological - agitation, anxiety, confusion, ataxia
- Cardiovascular - tachycardia, hypertension
- Hyponitraemia
- Hyperthermia
- Rhabdomyolysis
What is the management of ecstasy toxicity?
- Supportive measures
* Dantrolene may be used for hyperthermia if simple measures fail
