General internal medicine handbook Flashcards
What is treatment for BDZ overdose?
- Supportive measure is the mainstay of treatment
- Flumazenil: the aim is to reserve respiratory depression.
- Start with 0.2 mg IV, wait for 30 secs and titrate up to 1–2 mg in total
C/I : patient with undifferentiated coma, epilepsy, benzodiazepine dependence, co-ingestion of pro-convulsion poisons; e.g. TCA
What is the treatment of opioid overdose?
- Supportive measure is the mainstay of treatment
- Naloxone: the aim is to reserve respiratory and/or CNS depression. - Start with 0.4 mg IV, wait for 60 s and titrate up to 2 mg in total.
- For chronic user, start with low dose of 0.1 mg.
- Naloxone infusion if repeated administration of naloxone needed.
(2/3 of initial effective naloxone bolus on an hourly basis: i.e. 4initial effective dose + 500ml NS, Q6H).
What is the treatment of paracetamol overdose?
- Acute toxic dose: >150 mg/kg
- Activated Charcoal if within 1st hour, N-acetylcysteine (NAC) if toxic level above Tx line
- NAC has full protection if given within 8 hours post-ingestion, useful even on late administration
What is the management for immediately life threatening SVCO?
Stabilize airway, breathing, circulation
Urgent Oncology consultation for immediate chemotherapy for chemosensitive tumours
Urgent endovascular stenting can provide the most rapid relief
without affecting subsequent tissue diagnosis. Total SVC occlusion and SVC thrombus are not absolute contraindications for stenting. Post stenting short-term anti-thrombotic therapy recommended e.g. dual antiplatelets for 3 months (if no contraindication).
What is the management for stable SVCO patients?
Clinical examination and investigations targeted to establish tissue diagnosis by minimally invasive methods.
Sputum cytology, serum AFP, βHCG levels, LN biopsy, pleural
fluid cytology/pleural biopsy, bone marrow biopsy, endoscopic
biopsy, image-guided biopsy.
For suspected lymphoma, excisional biopsy of enlarged lymph node is essential ± bone marrow biopsy
Watch out for coexisting pericardial effusion/cardiac tamponade.
What is treatment of SVCO?
Empirical
Prop up for head elevation
Oxygen supplement
Dexamethasone 4 mg q6h iv
Disease-specific (Consult Oncology): Chemotherapy, Radiotherapy, Targeted therapy
Presence of SVC thrombus
Thrombolysis (mechanical/pharmacologic) may be considered in patients with extensive thrombus causing severe symptoms, balancing risks of bleeding.
Long term anticoagulation, if not contraindicated, for 3–6 months AND preferably continued beyond 6 months in those with active cancer or receiving chemotherapy (ASCO guideline 2015 update). LMWH is preferred over warfarin in malignancy-related thrombosis for its lower rate of recurrent thromboembolism and less drug interaction with subsequent systemic cancer therapy. Both have similar bleeding risks.
What is the general measures for acute poisoning?
- Maintain ABC, close monitor vital signs and neurological status
- External decontamination and beware of secondary contamination
- Obtain history of offending poison, dose, dosage form (susained release (SR) preparation), timing of ingestion
- Ix: CBP, L/RFT, glucose, H’stix, blood gas, lactate, osmolality. Urine, blood,+/-gastric contents for toxicology.
Specific drug level: paracetamol, ethanol, salicylate, as indicated
ECG (assess for HR, QRS, QTc, arrhythmia)
Imaging for body packing or massive SR pills poisoning
Correct fluid, electrolyte, acid/base disturbance and treat arrhythmia
Psychiatry consultation, suicidal precautions as appropriate
What GI decontamination techniques may be considered for acute poisoning?
- Activated charcoal: within first 1-2 hour after toxic ingestion. dose: 50-100g PO. Not for small molecuels (Fe, Li, toxic alcohols), caustic, hydrocarbon. Intubation and NG tube needed for unconsious patient. C/I: absent bowel sound or bowel perforation
- Gastric lavage (GL): potentailly life threatening poisonous ingestion. Consious patient must be cooperative, consent signed, lying head down left lateral position, with powerful suction standby. 36-40F orogastric tube, 200-250ml water each time for at least 4-6L or until return fluid is clear
- Multiple dose activated charcoal (MDAC): 1g/kg PO, followed by 0.5g/kg q2-4h for 1-2 days. Consider for theophylline, phenobarbital, phenytoin, digoxin, carbamazepine, dapsone, GI concretion forming drug; aspirin and sustained release preparation
- Whole bowel irrigation (WBI): toxic dose of SR preparation, body packers and drugs not absorbed to AC. PEG 1-2L/hr till clear rectal effluent (orally or via a NG tube). C/I: absent bowel sound or bowel perforation
What is the use of antidotes and enhanced elimination as needed in acute poisoning?
Specific antidotes: level 1,2,3 antidotes kept at acute hospitals, cluster hospitals and HKPIC respectively
Enhanced elimination as needed
Urinary alkalinization
* Useful in aspirin, phenobarbital, chlorpropaide, formate, methotrexate
* 1-2mmol/kg NaHCO3- IV bolus, then 50 mmol NaHCO3 (8.4%) in 500ml D5 Q4-6H IV infusion
* Works by ion trapping, must get urine pH>7.5 to be effective
What is the treamtent and management for methamphetamine/amphetamine/cocaine overdose?
- Agitation, hyperthermia: rapid cooling, IV BDZ
- Diazepam 0.1-0.3mg/kg IV bolus; cumulative doses up to 50-100 mg may be required
- HT: phentoalmine 1-5mg IV and repeat every 10 mins or nitroglycerin 0.25-5mg/kg.min
- Avoid BB alone for the unopposed alpha sympathetic effects
- Cocaine (Na channel blocking effect): NaHCO3- 1-2mmol/kg/ IV bolus till QRS <100ms or pH>7.55
What is the treatment of salicylate overdose?
- > 150mg/kg acetylsalicylate (aspirin) potentially toxic
- Pure methyl salicylate (oil of wintergreen): 10ml –> 14g of salicylate
- Ix: R/LFT, blood gas, serial salicylate level, glucose, urine ketone
- Consider GL, AC, MDAC, WBI
- Hydration, urine alkalinization if ASA >40mg/dL
- HD if end organ failure or ASA >100mg/dL or failed urine alkalinization
What is the treatment of anticholinergic poisoning?
- Physostigmine in selected case: 0.5–1mg slow IV, repeat up to 2mg C/I: TCA, widen QRS, CV disease, asthma, gangrene.
What is the treatment of BB overdose/CCB overdose?
- GI contamination, haemodynamic and cardiac monitoring
- Treatment options for bradycardia and hypotension
- Atropine: 0.6mg IV (up to 3mg) and iv fluid
- Glucagon: 2-5mg IV over 1 min (up to 10mg) followed by 2-5mg.hr in D5 (for B blocker poisoning)
- High dose insulin euglycemia therapy to enhance tissue perfusion (early use): regular insulin 1 units/kg IV bolus + dextrose 0.5g/kg/IV bolus. Regular insulin infusion starting at 0.5-2 units/kg/hr and increased by 2 units/kg/hour if no increase in cardiac output or clinical improveemnt up to 10 units/kg/hour
- Inotropes: adrenaline (0.02mg/kg/hr/min and titrate up), noradrenaline (0.1mg/kg/min and titrate up), dobutamine (2.5mg/kg/min and titrate up), isoproterenol (B agonist): 0.1mg/kg/min and titrate up, vasopressin (2 IU/hr and titrate)
- IV lipid emulsion: intralipid 20% 1.5ml/kg IV over 1 min, followed by 15ml/kg.hr over 30-45 min IV infusion
- NaHCO3- 1-2mmol/kg IV bolus for propranolol poisoning if QRS >100ms, repeat as indicated
What is the treatment of digoxin overdose?
- Ix: RFT, digoxin level, ECG
- GI decontamination: consider GL, AC, MDAC
- IVF to correct dehydration
- Bradydysrhythmias: atropine
- Tachydysrhythmia: Tx hypoK, hypoMg, lignocaine, amiodarone
- Cardioversion: may precipitate refractory VT, VF, start with low dose: 10-25J, pre-Tx with lignocaine or amiodarone
Digoxin immune Fab fragments (Digifab in HA) indications - Brady or ventricular arrhythmia not responsive to atropine
- Serum K>5mmol/L in acute DO
- Digoxin levle: 10-15ng/mL in an acute DO
- Digoxin ingestion of >10mg
Recommended dosage (50mg per vial) can be used with one of the below formulas
What is the management guideline for warfarin patient with over anti-coagulation?
Symptomatic and anti-Sx algorithm guideline
What is the treatment for dirct anticoagulant (DOAC) overdose?
- Inquire about last DOAC intake
- AC if within 2-4 hour of ingestion
- General Mx: IVF replacement, endoscopic or surgical haemostasis, blood and plasma transfusion (as plasma expander)
- For life threatening bleeding involving DOAC
- For rivaroxaban, apixaban or endoxaban: PCC 50IU/kg IV; consider rF7a (novoseven) 90IU/kg.
- For dabigatran: consider idarucizumab 5g IV; consider haemodialysis or haemoperfusion
What is the treatment for theophylline poisoning?
What is the treatment for sulphonylurea or insulin secretagogue poisoning?
- AC, GL if ingestion <1 hr; consider MDAC / WBI in severe case
- Oral feeding is allowed in conscious patient
- Monitor conscious level, correct hypokalaemia, hypophosphataemia, hypoglycaemia
- Consider thiamine 100 200mg IV prior to dextrose in alcoholic or malnourished patient
- D50 0.5 1g/ kg IV bonus preferably through central line
- Glucagon 5mg IM if fail to establish venous access
- In refractory hypoglycaemia (requiring repeated dextrose IV bonus or
escalating concentrated dextrose infusion), consider early use of octreotide 0.05 mg Q6H SC or IV (to reduce the risk of glucose-induced insulin release in SU poisoning) - Urine alkalinsation can be useful in chlorpromazine poisoning
What is general management of antipsychotics poisoning?
- Supportive care, ECG, GI decontamination as indicated
- Hypotension: IV fluid, inotropes
- Cardiotoxicity, widen QRS: treat like TCAs
- Dystonia: diphenhydramine 10mg IV or benztropine 1mg IM
- Look out for neuroleptic malignant syndrome
What is the treatment for TCA overdose?
What is the treatment for SSRI overdose?
- Supportive care, ECG,GI decontamination as indicated
- Treatment for serotonin syndrome (SS) if present
- Remove offending drugs, hydration, cooling, BDZ
- Cyproheptadine (8-12mg, then 2mg q2h, up to 32mg in first 24hour), neuormuscular blockade
- Citalopram: observe for >24 hour, cardiac monitoring (for prolonged QT, torsades de pointes (esp with dose >400mg)
- Venlafaxine: seizure; esp with dose >1.5g, prolonged QRS
What is the treatment for lithium poisoning?
- Ix: RFT, serum Lithium level q4h, AXR, ECG
- Serum Li level correlates poorly with CNS toxicities
- GI decontamination: GL, WBI
- Volume replacement and correction of hypoNa
Haemodialysis indication
* Neurotoxicity (depressed consiousness, cerebellar signs, or convulsion) irrespective of Li level
* Impaired renal function
* Acute Li poisoning with serum Li level >5mmol/L
* Chronic Li poisoning with serum Li level >2.5 mmol/L
End point of HD
* Neurotoxicity subsided and
* Li level remains stable at <1mmol/L (serum Li level may rebound after stopping HD, continuous monitoring as needed after stopping HD)
Continous RRT is an acceptable alternative if HD is not available
What is the treatment for carbamate poisoning?
What is the treatment for paraquat poisoning?
What is the treatment for household poisoning?
What is the treatment for methanol/ethylene glycol (EG) poisoning?
Ix: Blood: CBP, LRFT, ethanol level, anion gap, osmolar gap, methanol or ethylene glycol level
Urine for Ca oxalate and fluorescence [in EG poisoning]
What is the treatment for cyanide poisoning?
- ABC monitoring and supportive measures
- Surface decontamination and staff protection
- Treat seizure, hypotension and correct metabolic acidosis
- GI decontamination: consider AC +GL if ingestion within 1 hour
- Ix: RFT, ABG, lactate, AV O2 gradient (PaO2-PvO2), CO-Hb, met-Hb, blood cyanide level (confirm dx but not affect initial mx). Early use of antidotes in clinically suspected case: lactate >7mmol/L, high anion gap metabolic acidosis and reduced AV O2 gradient
What is the treatment for carbon monoxide poisoning?
- Pulse oximeter cannot detect CO-Hb; can be misleading
- look for features of tissue hypoxia (CNS,cardiac,metabolic)
- CO-Hb does not correlate clinical severity and/or outcome
- Indications for consideration of Hyperbaric oxygen treatment(HBO)
Loss of consciousness, coma, seizures
Confusion, cognitive deficits, focal neurological findings, visual symptom
Myocardial ischemia, life threatening arrhythmias
Persistent symptoms (after normobaric O2): headache, ataxia, abnormal
neuropsychiatric test
CO-Hb level > 25% or >15% if pregnant woman / child
What is the management algorithm for smoke inhalation?
What are the SS for snake bite?
What Ix should be done?
What is the treatment for snake bite?
Define hypothermia
What are the Ix and Mx for accidental hypothermia?
Define heat stroke
Compare the features of heat stroke vs heat exhaustion
What is the management?
What is the Ix and Mx for near drowning patients?
What is the Ix and Mx for electrical injury?
What is the Mx of rhabdomyolysis
What is the causes of SVCO?
PE
DDx
Ix
Tx
What is the Tx for malignancy related superior vena cava syndrome?
What are the causes of hypercalcemia of malignancy?
What is oncology workup?
What is hte Ix, Dx, prophylaxis and Tx for tumor lysis syndrome?
Define extravasation of chemotherapeutic agents and what are common vesicants?
How to porevetn extravasation?
What is the Mx when extravasation is suspected?
What are the preconditions and exclusions for considering dx of brain death?
What are the tests for confirming brain death?
- All brainstem reflexes must be absent.
- The testing of all the following is considered sufficient
a) Both pupils: fixed in diameter and non-reactive to light
b) Absence of bilateral corneal reflexes
c) Absence of VOR: no eye movement occurs in both eyes during or after the slow injection of at least 50ml ice cold water into at least 1 external auditory meatus or preferably into each external auditory meatus in turn.
d) No motor responses within the trigeminal nerve distribution can be elicited by adequate pain stimulation of any somatic area
e) Absence of gag reflex
f) Absence of cough reflex
g) Testing for apnea: should be done last. No respiratory movements occur when the patient is disconnected from the mechanical ventilator for long enough to ensure that the pCo2 rises above the threshold for stimulating respiration. In patients with pre-existing hypercapnia, it is recommende to wait for a pCO2 rise of >2.7kPa above the chronic level, with a pH<7.3. ABG must be available for this test to be performed.
Period of observation and reteption of tests: 2 separate full exams should be performed. The 1st exam should be performed after all pre-conditions met, and after at least 4 hours of observation of coma (GCS of 3) with absent brainstem function. 2nd exam can be performed any time after 1st exam, so total period of observation is at least 4 hours. The minimum period of observation needs to be totally 24 hours after cardiorespiratory arrest.
What is the clinical featrures of SJS and TEN?
What percentage of epidermal detachment?
What are the prognostic factors for SJS/TEN?
What is the discharge and follow up for SJS/TEN?
