eScript Flashcards
what side effects can oxybutynin cause?
Oxybutynin is an antimuscarinic drug, the adverse effects of which include dry mouth, constipation, blurred vision and occasionally cognitive impairment
Older adults may be more susceptible to these adverse effects
Cognitive impairment can increase the risk of non-adherence
what is adherence?
“The extent to which the patient’s behaviour matches agreed recommendations from the prescriber”
what is compliance?
the extent to which the patient’s medicines-taking behaviour matches the prescriber’s recommendations
OLD TERM
why do thiazide diuretics cause gout?
increase uricaemia, which may precipitate gout in susceptible patients
what drug commonly causes myalgia?
statins
The risk is increased if the statin is prescribed at a high dose or if it is prescribed in combination with a fibrate, macrolide antibaterial or certain calcium-channel blockers.
Treatment should be discontinued if creatine kinase is 5 times the upper limit of normal or if symptoms are severe.
what common drug may cause mood changes?
systemic corticosteroids
what is bioavailability?
the extent to which a drug reaches the systemic circulation where it is available to act at the ‘effector site’ (e.g. the brain for a sedative effect
what is bioavailability of IV drugs?
100%
what is the pathway of oral drugs into systemic circulation?
mouth-> stomach (disintegration of the formulation)-> small intestine (absorption) -> liver (metabolised)-> absorbed into systemic circulation-> effector site -> kidneys (elimination)
are lipid-soluble drugs absorbed better or worse?
better
are protein-bound drugs absorbed better or worse?
worse
what drug metabolism can erythromycin inhibit?
warfarin
what drug metabolism can phenytoin induce?
antiepileptics
what drug metabolism can rifampicin induce?
oestrogen in COCP
what drugs should not be crushed and why?
MR drugs e.g. nifedipine
Enteric-coated e.g. aspirin
they can alter pharmacokinetic profile of a drug by breaking down coating of a drug which are designed to prevent breakdown, so it is absorbed quicker
other side effects of crushing drugs
bad taste e.g ibuprofen
damage skin of handlers
what is a pro-drug and examples?
when a drug is metabolised in the liver to an active form e.g. codeine to morphine, azathioprine to mercaptopurine
why are drugs metabolised in the liver?
Once absorbed, the body treats all drugs as foreign molecules. It will attempt to metabolise them in the liver to water soluble compounds and excrete them via the urine.
Pre-systemic metabolism of oral drugs (termed the ‘first-pass effect’) can significantly reduce drug bioavailability (propranolol, morphine).
what is Volume of Distribution (Vd)
the theoretical volume of fluid that would be needed to achieve the actual plasma drug concentration
Vd is typically reported in (ml or litre)/kg body-weight
If a 1 gram (1000 mg) dose of drug X, given intravenously gives a plasma-drug concentration (Cp) of 50 milligrams/litre, then
Vd = 1000/50 Vd = 20 litres
will drugs with a high Vd have a high or low plasma concentration
low
what type of drugs have a low Vd?
highly water soluble (e.g. gentamicin, atenolol, and insulin) or extensively protein-bound (e.g. warfarin) as they stay in the plasma (blood)
what type of drugs have a high Vd?
highly lipid soluble (e.g. digoxin, morphine, and diazepam) as they go out of plasma into tissues and organs
when is protein binding important in warfarin?
In general, drugs are not metabolised when they are protein-bound. However, protein-bound drugs can act as a ‘reservoir’ of the active drug. For example, warfarin is 97% protein bound. The remaining 3% - the fraction unbound (fu) is active. If another drug (e.g. sulphonamide component of co-trimoxazole) were to displace warfarin from its plasma-protein, the risk of adverse effects and toxicity will transiently increase
what can affect plasma protein concentration?
disease states
pregnancy
malnutrition
how many half lives does it take for 97% of a drug to be eliminated?
5
what is the difference between first order and zero order elimination?
first order is independent of drug conc- conc is halved every half life
zero order is when there is a fixed amount of the drug reduced every hour, as it is dependent on enzymes that become saturated. e.g. ethanol removal from the body
what is clearance of a drug?
the hypothetical volume of blood from which the drug is completely removed per unit time. It is expressed as units of volume per unit of time (e.g. litre/hour or ml/minute).
what enzyme is mainly responsible for the metabolism of drugs?
P450
what 2 factors determine the proportion of drug metabolised?
Liver function (presence of cytochrome P450 enzyme).
Hepatic blood flow - can be decreased in shock and gastrointestinal surgery, affecting the amount of drug presented to the liver.
name a drug that induces P450
phenytoin
name a drug that inhibits P450
erythromycin
what should be calculated to assess the degree of renal impairment?
creatinine clearance
what drugs require therapeutic drug monitoring?
digoxin
gentamycin
lithium
vancomycin
what are the 3 parameters of pharmacokinetics of a drug?
volume of distribution
half-life
clearance
how can you estimate a child’s weight?
(Age +4) x 2 (kg)
how many micrograms in a milligram (mg)?
1000
what is %w/w, %w/v and %v/v?
%w/w is percentage weight per weight. A 1% w/w preparation contains 1 g of drug in 100 g of diluent
e.g. Hydrocortisone 0.5% w/w contains 0.5 g of hydrocortisone in 100 g of diluent
%w/v is percentage weight per volume. 1% w/v solution contains 1 g of drug in 100 ml of diluent.
e.g. Sodium chloride 0.9% w/v contains 0.9 g of sodium chloride in 100 ml of water for injection
%v/v is percentage volume per volume. A 1% v/v solution contains 1 ml of liquid drug/chemical in 100 ml.
ChoraPrep® contains 70 ml of isopropyl alcohol in 100 ml of solution (i.e. 30 ml of diluent)
convert sodium chloride 0.9% into mg/ml?
0.9%= 0.9g in 100ml
= 900mg in 100ml
= 9mg/1ml
how much glucose is in 5% solution?
5g in 100ml
what does adrenaline 1:1000 and 1:10000 mean?
1: 1000 = 1g in 1000ml= 1mg in 1ml
1: 10000= 1g in 10000ml = 0.1mg in 1ml
how is acetylcysteine prescribed?
calculated on patients body weight (max 110kg)
prescribed in 3 parts:
The first (or loading dose) is given over 1 hour in 200 ml of glucose 5%.
The second is given over the next 4 hours, in 500 ml of glucose 5%.
The third and final is given over the next 16 hours, in 1 litre of glucose 5%.
For the first you need 150 mg/kg.
For the second you need 50 mg/kg.
For the third you need 100 mg/kg.
That’s a total dose of 300 mg/kg over 21 hours
how is severe unexplained hypoglycaemia investigated?
blood samples- lab glucose
serum- insulin, C-peptide, insulin-like growth factor, 3-beta-hydroxybutyrate
what is the first step in management of DKA?
fluid resuscitation
what level of blood glucose is classed as a hypo?
<4
what are the 2 classifications of symptoms of hypos?
Autonomic (adrenergic) symptoms: as a result of activation of the sympathetico-adrenal system. These effects may be suppressed in people taking non-cardioselective beta-blockers (such as propranolol).
Neuroglycopenic symptoms: due to cerebral glucose deprivation. In more serious cases, this can lead to a loss of consciousness, seizures, and death.
examples of adrenergic effects of hypos?
sweating palpitations tachycardia pallor hunger restlessness
examples of neuroglycopenic effects of hypos?
confusion slurred speech drowsiness numbness of nose, lips and fingers anxiety blurred vision
do frequent episodes of hypolglycaemia increase or reduce awareness?
reduce
lifestyle and medical risk factors of hypos?
- lifestyle- diet, age, exercise, impaired awareness, ramadan
- medical- incorrect insulin prescription/administration, comorbidities, illness, discontinuation of long term steroids, dialysis, AKI, learning difficulties
mx of a hypo in a conscious person who is symptomatic with BG >4?
Give a small carbohydrate snack, such as a banana, slice of bread or a usual meal if this is due.
Take a blood glucose concentration at 10 minutes to ensure the hypoglycaemia has resolved.
mx of a hypo in a conscious person with BG <4?
Give 15-20 g of quick acting carbohydrate of the patients choice:
- 4-5 Glucotabs® (5-7 Dextrosol® tablets) or sweets such as 4 large jelly babies or 7 large jelly beans.
- 1 bottle (60 ml) of Glucojuice®.
- 150-200 ml pure fruit juice.
- 3-4 heaped teaspoons of sugar dissolved in water (note: not suitable if taking acarbose).
Repeat the blood glucose 10-15 minutes later.
If the blood glucose is still below 4.0 mmol/litre, repeat the administration of quick-acting carbohydrate for up to three cycles.
If it remains below 4.0 mmol/litre, after three cycles (30-45 minutes) consider administration of intramuscular glucagon 1 mg or glucose 10% infusion 150-200 ml over 15 minutes.
When blood glucose is above 4.0 mmol/litre the patient should consume a small (20 g) long-acting carbohydrate snack such as a slice of toast or a usual meal if this is due to prevent recurrent hypoglycaemia. Patients administered glucagon should be given a larger carbohydrate snack (40 g) or meal to enable glycogen stores to be replenished.
mx of a hypo in a confused or uncooperative person?
1.5-2 tubes of Glucogel® or Dextrogel®
Squeezed into the mouth between the teeth and the gums.
OR
Intramuscular glucagon 1 mg (this may only be administered once)
Note it may take 15 minutes to observe the effect.
(then follow protocol as per)
mx of a hypo in a semi- conscious or unconscious person with IV access?
Give 75-100 ml of glucose 20% over 15 minutes via a standard giving set.
OR
Give 150-200 ml of glucose 10% over 15 minutes. If an infusion pump is available use this, but do not delay administration.
Repeat blood glucose at 10 minutes. If blood glucose remains below 4.0 mmol/litre, repeat administration.
mx of a hypo in a semi- conscious or unconscious person without IV access?
Give intramuscular glucagon 1 mg (GlucaGen Hypokit®, this may only be administered once).
Note that it may take 15 minutes to see the effects.
Glucagon may be less effective or ineffective in patients under the influence of alcohol, taking sulfonylureas, those chronically malnourished or in a prolonged period of starvation
what Ix and Mx to do in an unexplained hypo?
Take blood samples for a laboratory glucose to be measured urgently, and for serum to be stored to measure insulin, C-peptide, and insulin-like growth factor (also 3-beta-hydroxybutyrate if you can).
Give enough glucose orally or intravenously (use 20% glucose solution) to restore the blood glucose to normal (see previous guidance).
possible causes of an unexplained hypo?
Insulinoma- high insulin and C peptide
Insulin poisoning- high insulin
Fasting alcoholic ketosis
when to DVLA need to be informed about a diabetic for lorry drivers and normal vehicles?
For lorry and/or bus drivers, the DVLA should be informed about treatment with any oral antidiabetic or insulin.
For other drivers, the DVLA should be informed if they are treated with insulin.
Other indications for informing?
- Has more than 1 episode of severe hypoglycaemia within the preceding 12 months, or of any severe episode if driving a bus or lorry.
- Has impaired awareness of hypoglycaemia.
- Has suffered a hypoglycaemic episode whilst driving.
3 features of DKA and numbers?
- Hyperglycaemia: with a blood glucose > 11.0 mmol/litre (or known diabetes mellitus).
- Metabolic acidosis: bicarbonate (HCO3) < 15.0 mmol/litre and/or venous pH < 7.3.
- Ketonaemia: blood ketones (3-betahydroxybutyrate) ≥ 3.0 mmol/litre or significant ketonuria (more than 2+ on standard urine sticks).
principles of treatment for DKA?
Replace fluids.
Correct electrolytes abnormalities.
Replace insulin.
Gradually reduce the serum glucose concentration.
Gradually correct ketosis.
Identify treatment of co-morbid precipitants.
protocol for DKA in the 1st hour?
- Commence fluid replacement with 500 ml sodium chloride 0.9% over 15 minutes.
- Give an additional 500 ml sodium chloride 0.9% over 45 minutes (total 1 litre in the first hour).
- Commence a fixed rate intravenous insulin infusion with 50 units of Actrapid® or Humulin S® made up to 50 ml with sodium chloride 0.9%, infused at a rate of 0.1 units/kg/hour (for example, a patient weighing 60 kg would receive 6 units/hour).
- Monitor clinical parameters and biochemical markers.
- Establish a monitoring regimen for blood glucose and ketone concentrations (local protocol is likely to state a frequency).
- Give a prophylactic dose of the formulary low molecular weight heparin (if this is not contraindicated).
what to give if there is a delay in insulin prescribing in DKA?
a single bolus dose of intramuscular insulin (0.1 units/kg) can be administered.
what monitoring to do for DKA for electrolytes?
Ketones: measure every hour. The concentrations should fall by 0.5 mmol/litre/hour. If it is not falling, the patient may require an adjusted rate of insulin infusion.
Capillary glucose: measure every hour. The concentration should fall by 3 mmol/litre/hour.
Ensure the patient’s usual long-acting insulin regimen is prescribed and administered at the normal time.
When DKA has resolved, convert patient back to an appropriate subcutaneous regimen.
when should you replace potassium in DKA?
Give 40 mmol/litre of replacement fluids for serum concentrations between 3.5-5.5 mmol/litre.
Seek senior review if the serum concentration falls < 3.5 mmol/litre.
What medication for T2DM can cause DKA that patients need to be counselled about?
SGLT2 inhibitors e.g. canagliflozin, dapagliflozin, empagliflozin
Risk factors for developing DKA whilst taking an SGLT2 inhibitor?
low beta-cell function, restricted food intake, dehydration, acute illness (altered insulin requirements), surgery and alcohol misuse.
what DKA symptoms should you tell a patient to look out for?
weight loss, nausea, vomiting, fast breathing, stomach pain and a sweet smell to the breath.
risk factors for Hyperosmolar Hyperglycaemic State
older age
comorbidities
severely dehydrated
first presentation of diabetes
complications of HHS?
vascular complications (myocardial infarction, stroke or peripheral thrombosis), seizures, cerebral oedema and Central Pontine Myelinolysis (CPM).
features of HHS?
Hypovolaemia. Marked hyperglycaemia (≥ 30 mmol/litre). Raised osmolarity (≥ 320 mosmol/kg).
No ketones or acidosis
4 principles of treatment for HHS?
- normalise osmolarity
- replace fluids- 1 litre 0.9% saline
- monitor and replace electrolytes
- normalise blood glucose- no insulin. The blood glucose concentration will start to fall as the patient is rehydrated. Aim for a reduction of 5 mmol/hour.
- LMWH
what are the main contributors to osmolarity and how is it calculated?
glucose and sodium
Osmolarity can be calculated using the formula 2Na+ + glucose + urea.
in management of DKA, should normal insulin regimes be continued?
yes
pathophysiology of allergic drug reaction?
mast cells can be activated via Immunoglobulin E (IgE) (e.g. penicillins) or directly by the drug (e.g. aspirin, contrast media)
they release histamine which causes symptoms
symptoms of type 1 allergic reaction?
wheeze itching angioedema hypotension urticaria
name some non-allergic drug reaction?
Morbilliform rash
Erythema multiforme
Fixed drug eruptions
Photosensitivity
what is morbilliform rash?
resembles urticaria but the lesions enlarge and become confluent over several days, whilst the individual lesions of urticaria subside and reappear in different areas
what drugs may cause erythema multiforme?
penicillins, phenytoin and statins. It can rarely progress to Stevens-Johnson Syndrome and the potentially fatal Toxic Epidermal Necrolysis (TEN).
what are fixed drug reactions and causes?
erythematous plaques that recur in the same place each time the causative drug is taken. Causes include paracetamol, tetracyclines and non-steroidal anti-inflammatory drugs (NSAIDs).
what is the most common drug reacting drug class?
penicillin and cephalosporins e.g. cefalexin
both have a beta-lactam ring
also carbapenems e.g. meropenem
how long should patients be observed after a drug reaction?
6-12 hours
what drug can cause a pure angioedema rash?
ACE inhibitors
common drug reactions?
chlorhexadine NSAIDs penicillins opioid analgesics muscle relaxants plasma expanders radiocontrast media
what medication should be given in mild allergic reaction?
chlorphenamine
what is the treatment of severe allergic reaction?
IM adrenaline 0.5mL of 1:1000 , 500mcg
IV or IM 10mg chlorphenamine
IV or IM hydrocortisone 200mg
Inhaled or IV salbutamol
mx of a patient following severe allergic reaction? (i.e. recovered)
Prescribe prednisolone for up to 3 days.
Prescribe a non-sedating antihistamine for up to 3 days (adhere to your Trust formulary).
Issue or recommend a medical alert band if re-exposure is possible.
Ensure the allergy is documented in the medical notes and on the drug chart (electronic or paper-based system).
Communicate information to the general practitioner.
Warn the patient if the drug or related drugs are found in medicines available over-the-counter (e.g. salicylates/acetylsalicylates in patients who have reacted to an NSAID). Advise they check with a pharmacist prior to self-medicating with over-the-counter medicines.
Provide structured written information to the patient.
Prescribe two adrenaline auto-injectors for self-administration only when there is a significant risk of re-exposure.
Report the adverse drug reaction to the yellow card
scheme.
Refer to an allergy clinic
what marker can be measured after anaphylactic reaction?
mast cell tryptase
In anaphylaxis, mast cell degranulation leads to increased blood tryptase concentrations.
what are the risks with IV adrenaline?
arrhythmias and life-threatening hypertension
if a patient is in VF or pulseless VT, when should adrenaline be given and what dose?
Adrenaline is not indicated until the third cycle of chest compressions- 1mg IV
is atropine given in cardiac arrest?
it is no longer recommended
how often should adrenaline be given in cardiac arrest?
every 3-5 minutes
what is the temperature aim in cardiac arrest?
aim to achieve a core temperature of no higher than 36°C. Passive cooling is appropriate.
what is the breathing that can be seen in cardiac arrest?
agonal breathing (gasps)- not to be confused with actual breathing
what is PEA?
pulseless electrical activity
any pulseless rhythm that is not defined by VF, VT or asystole
can look like a normal ECG
how often should cardiac rhythm be checked in cardiac arrest?
every 2 minutes
what other medication should be given in cardiac arrest expect adrenaline?
Give a single dose of intravenous amiodarone 300 mg after 3rd shock- only in a shockable rhythm
what should be done initially in a non-shockable rhythm?
CRP 2 mins
1mg IV adrenaline
repeat every 3-5 mins
what are the 8 reversible causes of cardiac arrest?
Hypoxia
Hypovolaemia
Hypo/hyperkalaemia
Hypothermia
Tamponade (cardiac)
Thromboembolism
Toxins - opioids, tricyclic antidepressants and benzodiazpeines
Tension pneumothorax
how is resuscitation different if core body temp is less than 30 degrees?
limit defibrillation attempts to three (delivered at maximum defibrillator output), and withhold intravenous drugs until the core body temperature increases to more than 30 °C. Withhold adrenaline and amiodarone until the patient has been warmed to more than 30 °C.
how is resuscitation different if core body temp 30- 35 degrees?
double the intervals between drug doses compared with normothermia intervals
mx of cardiac tamponade
pericardiocentesis
how to manage a cardiac arrest in a pregnant woman in the later stages of pregnancy?
manually displace the uterus to the left. This relieves pressure of the gravid uterus on the caval vessels, improves venous return and makes cardiac compressions more effective. Add left lateral tilt only if this is feasible. You may need to place your hand position for chest compressions higher than normal (2-3 cm) for patients with advanced pregnancy (more than 28 weeks) to allow for displacement of the contents of the chest by the uterus.
Consider emergency caesarean section if initial resuscitation attempts are unsuccessful. This decision should be made within 5 minutes of cardiac arrest.
mx of cardiac arrest following cardiac catheterisation
give a series of three stacked DC shocks
what happens in post cardiac arrest syndrome?
brain injury caused by the effects of hypoxia, myocardial dysfunction, the systemic response to ischaemia and reperfusion, and the potential ongoing effects of the initial cause of the cardiac arrest. This can lead to multi-organ failure.
how to prevent post cardiac arrest syndrome?
continue oxygen therapy
temperature management of no higher than 36 degrees
PCI if cardiac arrest caused by myocardial ischaemia
name a benzodiazepine antagonist?
flumazenil
- not used in diagnostic trial as can precipitate seizures
when else is flumazenil given?
may prevent the need for ventilation, particularly in patients with severe respiratory disorders (e.g. COPD)
things to establish in a drug OD history?
The likely agent(s) involved, including co-agents (e.g. alcohol).
Date and time of ingestion.
Quantity ingested.
Route of exposure.
Whether exposure is a single overdose, staggered, or chronic.
signs of amitriptyline overdose?
Coma, hypertonia, dilated pupils, urinary retention, sinus tachycardia, hyper-reflexia. Tricyclic antidepressants have significant anticholinergic activity, causing tachycardia, dilated pupils and urinary retention.They are cardiotoxic in overdose.
signs of heroin overdose?
Coma, constricted pupils, reduced respiratory rate. A classical opioid triad; not all features need be present in cases of poisoning.
also hypotension, bradycardia
signs of ecstasy overdose?
Delirium, tachycardia, agitation, dilated pupils, hyperthermia. Amfetamine derivatives cause sympathetic overdrive.
aims of managing drug poisoning?
- Reduce absorption
- Give an antidote
- Increase elimination
how to reduce absorption in drug overdose?
- activated charcoal
- gastric lavage
- whole bowel irrigation
antidote for beta blockers?
glucagon
antidote for paracetamol?
acetylcysteine
antidote for opioids?
naloxone
how to increase elimination of a drug?
- multiple dose activated charcoal
- Urine alkalinisation
- Dialysis and haemoperfusion
how many hours after paracetamol ingestion do you have to wait for an accurate plasma-paracetamol conc?
at least 4 hours
4-13 hours usually, if there is a late presentation it is no reliable so go off evidence of liver damage from pro thrombin time, LFTs or phosphate (in which NAC therapy is still effective)
what is a staggered overdose?
when a potentially toxic dose of paracetamol is ingested over more than one hour
management of paracetamol overdose?
- If the patient presents within 1 hour of ingestion, activated charcoal may be of benefit.
- measure plasma-paracetamol level
- give NAC within 8 hours IV over a course of 21 hours
when can acetylcysteine be given before a plasma-paracetamol level is known?
- More than 8 hours has elapsed since overdose
- The overdose is staggered (plasma-paracetamol is uninterpretable and the treatment graph unreliable in patients who have taken a staggered overdose of paracetamol)
- If there is doubt over the time of paracetamol ingestion.
- Overdose of more than 150 mg/kg
complications of paracetamol OD?
Liver and renal failure can occur in patients who are untreated or who present late
Infusion reactions from acetylcysteine- rash and bronchospasm. If this happens, stop infusion and give an antihistamine and nebulised salbutamol. When the reaction has subsided, restart the infusion - often at a slower rate.
Ix in iron poisoning?
ABG FBC LFT AXR INR (prothrombin time) serum-iron conc
signs of iron overdose?
V&D black or grey stools GI ulceration GI haemorrhage Haematemesis Rectal bleeding CV collapse
mx of iron overdose?
- Admit patients who have ingested more than 20 mg elemental iron/ kg
- If the patient presents within 1 hour of ingesting the tablets then gastric lavage or aspiration may be attempted
- Take a serum-iron concentration. This will peak at approximately 4 hours post ingestion.
- The antidote for iron is desferrioxamine- it chelates iron
when to administer desferrioxamine without known serum iron conc?
There is a history of iron ingestion; AND
The patient has a reduced conscious level; OR
The patient is significantly hypotensive.
complications of iron overload?
orange-red urine from desferrioxamine therapy liver failure with haemorrhage hypoglycaemia hypotension intestinal infarction renal failure
can a trial of naloxone be used for a diagnostic test? and what dose?
yes
200 micrograms as a single intravenous dose immediately
what is the most common cause of salicylate poisoning?
aspirin
when should you repeat salicylate concentration?
2 hours
what ABG abnormality does salicylate poisoning cause?
metabolic acidosis due to an increase in cellular O2 consumption and a build up of acidic metabolites
Hyperventilation can also lead to respiratory alkalosis
what level is moderate salicylate poisoning?
more than 250mg/kg ingested
mx of salicylate poisoning?
If the patient presents within an hour of overdose, can give activated charcoal
Administer intravenous fluids to manage the patient’s hypotension and dehydration.
Measure the plasma-salicylate concentration and repeat every 2-3 hours until the salicylate concentration is no longer rising.
TOXBASE recommends considering urine alkalinisation if plasma salicylate concentration is greater than 500 mg/litre in adults or 350 mg/litre in children.
Maintain the urine pH at between 7.5 and 8.5. This can be achieved with the intravenous administration of sodium bicarbonate.
Monitor the potassium concentration as hypokalaemia may occur.
Consider haemodialysis in patients with severe toxicity (or a very high serum-salicylate concentration), especially where a patient has prognostically poor signs such as coma, non-cardiogenic pulmonary oedema, fever and severe acidaemia.
exam answer for salicylate poisoning?
Administer intravenous fluids
Perform a 12-lead ECG.
Consider the need for urinary alkalisation
Contact the NPIS
Contact the renal unit for haemodialysis
Repeat the salicylate concentration in 2 hours
what antidepressant is most likely to cause cardiotoxicity?
Tricyclic antidepressants
SNRI e.g. venlafaxine
classic signs on an ECG following TCA overdose?
tachycardia, widening of the QRS and QT interval, other conduction defects such as RBBB and often a negative R wave deflection in lead I.
features of TCA overdose?
anticholinergic SEs
The dry mouth, blurred vision, tachycardia, a hot dry skin ,urinary retention and drowsiness; reflected in the phrase: “hot as a hare, dry as a bone, blind as a bat, red as a beet, mad as a hatter, and full as a flask”.
features of SSRI toxicity?
N&V Agitation Serotonin syndrome Tachycardia Convulsions
mx of antidepressant overdose?
ECGs, ABG
Intravenous fluids.
Administer activated charcoal in patients presenting within 1 hour
Treat serotonin syndrome. You will need to treat the hyperpyrexia (if present) as well as using 5-HT antagonists.
Treat convulsions with a benzodiazepine
Avoid the use of anti-arrhythmics: cardiac arrhythmias will often resolve when you have corrected hypoxia and acidosis.
Consider sodium bicarbonate in patients with a broad-complex tachycardia or arrhythmia.
signs of amphetamine and cocaine overdose?
agitation convulsions hallucinations hyperthermia cardiac arrhythmias intracerebral haemorrhage rhabdomyolysis
mx of amphetamine and cocaine overdose?
Manage patients in a calm environment and away from loud noise and activity.
If a patient is severely agitated, sedate them with intravenous diazepam.
Where there is evidence of cardiac ischaemia in patients taking cocaine - diazepam, aspirin and nitrates are usually all that is required. Avoid beta-blockers owing to the risk of increasing coronary artery constriction. Thrombolysis is not indicated, though PCI may be beneficial.
Beta-blockers may be tried in patients suffering with amfetamine related symptoms (e.g. propranolol 40-80 mg orally).
In most cases hyponatraemia responds to fluid restriction.
Manage mild hyperthermia with conventional cooling measures - remove unnecessary clothing, use a fan, sponge with tepid water.
where do all patients who have taken an overdose need to be referred to?
psychiatric assessment
how to check what monitoring and tx needs to be given?
TOXBASE
what NEWS score should prompt looking for red flags of sepsis?
5
what are the red flags to look out for for suspected sepsis?
- CNS- new or altered mental state
- SBP- <90 or drop of >40
- HR- >130
- RR >25
- O2- needs O2 to maintain sats >92
- Skin- non-blanching rash, mottled/ashen/cyanotic appearance
- Oliguria
- Lactate >2
- Recent chemotherapy
- Immunosuppression in patients under 18
how many red flags are needed to prompt the sepsis 6 bundle?
1
what are the amber red flags for sepsis?
Relative(s) concerned about mental status
Acute deterioration in functional ability
Immunosuppressed
Trauma/surgery/procedure in the last eight weeks
Respiratory rate 21-24 breaths per minute
Systolic blood pressure 91-100 mmHg
Heart rate 91-130 or new dysrhythmia
Temperature < 36°C
Clinical signs of wound infection
The presence of any ONE Amber Flag sign should prompt what?
Send and review blood tests: full blood count, urea and electrolytes, c-reactive protein, clotting factors
Escalate: request senior clinical review within one hour
Consider: if antimicrobial treatment is required
what is septic shock?
Septic shock is identified using a clinical construct of sepsis with persisting hypotension requiring vasopressors to maintain MAP ≥ 65 mmHg and having a serum lactate level ≥ 2 mmol/litre despite adequate volume resuscitation.
what is cryptic shock?
where patients can have a high lactate concentration in the presence of a normal blood pressure. These patients may have sepsis and require urgent treatment.
what things need to be looked out for that can mask sepsis?
beta blocker use- lowering HR
paracetamol- masking a fever
cryptic shock
sepsis-induced hypotension
what are the O2 sats aim in sepsis?
94-98%
document if the patient doesn’t need O2
what bloods should be done in sepsis?
2x blood cultures
blood glucose, lactate, FBC, U&Es, CRP and clotting.
LP if indicated
how often should you repeat lactate in a sepsis case?
once an hour
should patients who have an AKI receive any different treatment for ABx?
All patients should receive a first full loading dose of each antimicrobial agent, irrespective of renal function.
Adjust subsequent doses according to renal function.
what 4 things to ask about before prescribing antibiotics?
allergies
recent travel
recent hospital admission
resistance and sensitivities
what NEWS2 score is high and moderate clinical risk?
7 is high
5-6 is moderate
