short case meds and metabolic Flashcards
clexane for DVT/PE + renal dosing prophylactic and treatment
Normal dosing
prophylactic - 40mg /24 hr
treatment
- 1.5mg /kg /24hr
high risk (obesity/symptomatic, cancer) 1mg/kg/BD
renal dosing eGFR <30
- prophylactic - 20mg/ day
- treatment 1mg up to 100u /kg /day
treatment of GCA
If suspected do ESR then
1. Prednisone 1mg/kg po daily for 4 weeks.
Then taper over 6-12 months with symptoms / ESR improvement
- If visual/ neuro symptoms 1. Prednisolone IV 1g for 3 days
- If confirmed - aspirin 75mg daily
- consider bone protection - VIt D, BP
What can you prescribe for constipation Non pharm, prophylactic and oral
Non pharm
1. regular toileting, increased dietary fibre, hydration and mobilisation
Prophylaxis
1. Stimulant + softener taken regular
eg. Docusate sodium (softener) + sennoside B (peristalsis stimulator)
= Laxsol 1-2 tab at night up to 4 tabs
NB cannot use stimulants in bowel obstruction
- Molaxole or lactulose (osmotic agents) added
NB avoid softeners in spinal cord compression
- Rectal interventions
- manual evacuation of faecal impaction
If soft faeces: Microlette (sodium citrate osmotic enema)1-2 daily ( osmotic ) OR 1-2 Bisacodyl suppository (stimulant)
If hard faeces: 1-2 Bisacodyl suppository (stimulant)
+/ or 1-2 glycerol suppository (osmotic)
or microlette (osmotic)
Then
Rectal phosphates - Fleet enema (saline laxative)
what can you prescribe for nausea -moa, indication, SE, CI
1.Dopamine receptor antagonist (upper GI prokinetic) for general n+v
-Metoclopramide 10mg TDS PO/IV/SC :
Contra: GI obstruction/haemorrhage/parkinsons
-SE: extrapyramidal, drowsiness, restlessness, acute angle glaucoma. Note doses reduced in renal and hepatic impairment
- Domperidone -10mg TDS - dopamine receptor antagonist. CI: prolactinoma, GI obstruction, per or haemorrhage, long QT
-SE less central effects, dry mouth
- avoid in mod to severe hepatic impairment and reduce frequency in renal impairment - Antihistamine
Cyclizine 25-50mg TDS - h1 receptor antagonist with central anticholinergic effects. Good for n+V, vertigo and motion sickness
CI: GI obstruction, severe HF, severe Liver disease, acute porphyria
SE: sedation, anticholinergic, extrapyramidal, hypotension with IV, arrhyhthmia s
- not for severe liver disease - 5HT3 antagonist
eg. Ondansetron 4-8 mg BD . Good for post op and chemo/radiotherapy nausea
CI : long QT, hypokalaemia, hypomagnesmia, serotoninergic drugs
SE: constipation, flushing, headache
Max 16 per day in hepatic impairment - Dopamine antagonist (phenothiazine). N+V related to vertigo, radiation, neoplastic disease, opioids, anaesthetics, cytotoxics
Prochlorperazine 5mg BD/TDS PO or 3-6mg buccal BD
CI ; CNS depression, phaeochromocytoma, long QT
SE: extra pyramidal, anticholinergic, acute angle glaucoma
Start low in renal impariment and liver disease - Haloperidol 0.5-3mg PO/SC
Centrally acting sedative used in pall care good for opoid induced N+V , renal failure, hypercalcaemia
CI: parkinsons
what can you prescribe for pain
- paracetamol 0.5-1g Q4-6hourly max 4g daily
- NSAID - consider not long term GI bleeding, severe heart failure, pregnancy
- ibuprofen (200-400mg 2-4 times daily max 2.4 g daily
- celecoxib (selective COX 2 - less GI - 200-400mg daily in 1-2 divided doses
+/- PPI - omeprazole 20mg daily for 4 weeks if bleed
- Weak Opioids
-Tramadol 50-100mg BD + prochlorperazine 5mg BD
-Codeine 30-60mg Q4H max 240mg + Laxsol 1-2 tabs nocte - swap the opioids to Strong opioids + antiemetic+ laxative
- Morphine 5-10mg Q4H adjusted to response
first SA severidol every 4 hours, then BD modified release M-eslon
Oxycodone or Fentanyl when renal failure - po, IV , SC
2x morphine strength
OxyNorm (IR) 5mg Q4-6h
Oxycontin (MR) 10mg every 12 hours
Fentanyl via protocol
Provide PRN dose and review daily to see if prescribed doses accurate
- Adjuvants for neuropathic pain
a) TCA: SE: dry mouth, blurred vision
b) gabapentin or pregabalin: SE drowsiness, dizziness, ataxia - adjuvants for bone/ met pain, spinal pain, liver mets
Dexamethasone - Adjuvants for spasticity pain in MS, spinal cord, Baclofen 5mg TDS
what can you prescribe for DKA
- ABCD - secure 3x IV lines
- IV fluids within 30min - 0.9% NaCl 1000ml first hour, 500 mL per hour next 4 hrs.
- Add K+ per L of fluid depending on serum K
- at least 70 mmol in the first 24 hours - cardiac monitoring needed if infusion K+ rate >10mmol> hr - Insulin infusion units/hour based on schedule within 60 minutes
- Investigations
- VBG - bicarb
- U&E, Cr, Bhb, lactate
- Urinalysis, BC and CXR
-ECG
===Repeat serum K on VBG 3 times in first 24 hours
- FBC - Monitor vitals, fluid balance -?urinary catheter, NG.
6.Start Glucose Infusion when BG <13mmol - start sub cut insulin when pt well hydrated. VBG >7.35, and give insulin before next meal, discontinue insulin infusion 2 hours post meal
What are the presentations, investigations and management for hyperkalaemia (K= >6.5 mmol) - danger is VF
Presentation - fast irregular pulse, chest pain, palpitations, dizziness
Causes: renal failure, metabolic acidosis (secondary to sepsis, volume) K+ sparing diuretics (spironolactone) rhabdomyolysis, metabolic acidosis, burns, artefactual result
Ix
U+E, ECG, renal function
ECG : tall, tented T waves. Wide QRS which becomes sinusoidal then VT/ VF , flat p waves
Treatment
1.start ECG put on telemetry
2. SA insulin 10u + 50mL 50% dextrose over 10 minutes
+ 5 mg salbutamol nebulised hourly
3. Give calcium gluconate 10% injection over 10 minutes and titrating to ECG improvement
4. For acute case stop ACE and arbs. Stop any fluids with K+.
5. Assess fluid status and treat accordingly
6. Calcium resonium (-K+ binder in the gut) + lactulose
7. Increase K+ elimination - K+ losing diuretic = furosemide. Consider dialysis if not correcting
7. Fix underlying problem - treat acidosis with oral bicarb 840mg 2-3 BD or IV bicarb 8.4% 50mL over 2 hours and repeat
how do you interpret anaemia tests
- Hb
- high reticulocytes = haemolysis or post haemorrhage
NORMAL RETICs - Microcytic = do iron studies to differentiate
- iron deficiency (decreased everything, increased/normal TIBC)
from
- anaemia of chronic disease (ferritin increased , everything normal or decreased) or
- haemoglobinopathies (increased/normal ferritin everything) - macro = do TSH and folate/B12 - hypothyroidism, renal failure, myelodysplasia
- Normocytic anaemia can be mixed picture - do Cr, CRP, folate B12 + other tests looking for all macro and micro except for iron deficiency
What are the considerations for someone on long term steroids - SE, stress dosing, interactions, prophylactic needs
SE:
- weight gain, skin thinning,
- GI ulceration
-HTN
Muscle weakness
Immunosuppression
DM
Bone loss / increased # risk
Stress dosing in illness
- 2x regular dose for duration of illness/surgery/ flare and then gradually reduce
eg. IV 50-100mg hydrocortisone Q6-8h if severe flare.
Interactions: with NSAIDS/ warfarin to cause hypokalaemia
Prophylactic: vit D/bisphosphanates for those at risk of fracture
Physical activity. start low, go topical if can
What are the SE and contraindications of NSAIDS
GI bleeding - CI in aspirin, active GI ulcers
Renal impairment
CI in heart failure, increased risk of MI and stroke especially with smoking + drinking
Causes of hyponatraemia and how do you investigate/ manage
Signs of hyponatraemia = n+v, headache, confusion, seizures , oedema
- Hypervolaemic: nephrotic syndome HF, cirrhosis, RF
- Loop diuretics - monitor - Euvolaemic: do urine osmolality - if >300 than SIADH, if not then water intoxication, severe hypothyroidism, glucocorticoid insuficiency
Treatment for SIADH is r/v meds, fluid restrict
- Hypovolaemic: check urine Na+.
- If >20 then due to renal na+ loss in addisons, renal failure, diuretics, osmotic diuresis
- If no then loss by v+d, fisutale, burns, SBO, sweat
Treatment: IV 0.9% saline slowly - don’t increase Na more than 15mmol/L per day for central pontine myelinolysis
Hypernatremia treatment and cause and signs
signs: lethargy, thirst, confusion, coma, dehydration.
Causes: fluid loss (d+v+ burns), diabetes insipidus, iatrogenic (too much IV fluids)
Management is
- oral water if possible
Or IV glucose 5% slowly +
0.9% saline if hypovolaemic
Correction should not exceed 10-12 mmol per day
Meningitis ix and treatment
- Blood cultures
- Screen for encephalitis - GCS <14, seizures, altered behaviour, focal neurology
- Red flags - shock, sepsis, purpuric rash - IVabx immediately , call ID and ICU
IV ANTIBIOTICS
1. dexamethasone 10mg IV Q6H - discuss with ID after 4 hrs
2. Ceftriaxone 2g IV Q12H
- if immediate or delayed severe reaction - d/w OC ID or if cant then
- Vancomycin as per vanculator and aztreonam 2gIV and discsus
3. If risk factors for listeria eg. immunocompromise, >50. alcohol, pregnant then add benzylpenicillin 2.4g IV Q4H as resistant to ceph
4. If risk factors for s. pneumoniae (hospitalisation, sinus disease, frequent abx treatment, contact with daycare children) - Add Vancomycin
- CT head if neurology, papilloedema, >60yo, immunocompromise
- If no raised ICP then LP within 30 minutes or abx
- CSF analysis,
- gram stain and culture , PCR for enterovirus and HSV
- cytology
- rbc, WCC, protein,
- ZN stain for acid fast bacilli
- oligoclonal bands - Review results
bacterial - gram stain Or WCC >100 + polymorphs >50% or protein >0.5, <2.8 glucose
aseptic - nil on gram stain + WBC 5-230, lymphocytes >505
What medications prolong QT interval, what is QT interval (Q wave to T end (period of ventricular systole to relax)
QT prolongation is dangerous as associated with Torsades de Points and VT/F / sudden cardiac death
QT interval corrected is estimation of QT interval at standard HR of 60 bpm. Formulas use the QT / square root of RR interval in seconds
QTc prolonged if >440ms in men, or 460ms in women.
Associated with
Drugs
Antipsychotics, antiarrhythmics, TCA, antidepressants, Antihistamines, hydroxycholoroquines, macrolides
- hypokalaemia
- hypomagnesmia
- hypocalcaemia
-hypothermia
- MI
- raised ICP
How to interpret TFT - primary and secondary hypothyroidism, primary and secondary hyper
T3 is the active form, but majority release is T4 gets converted into T3 peripherally and is a negative feedback to the pituitary and hypothalamus
1’ hypothyroid eg. autoimmune thyroiditis, iodine deficiency, radiotherapy,
= reduced thyroid hormone secretion = low T4 and T3, raised TSH
2’ hypothyroid - rare - reduced TSH - from pituitary adenoma
= normal / low TSH due to lack of production
Low T4
1’ hyperthyroidism eg. Graves, toxic multinodular goitre,
= raised T3/4, low TSH
2’ hyperthyroidism
- TSH secreting tumour, HcG tumour
Raised T3/4 and raised TSH
Management of UGI bleed
- ABCDE
- Hx - coffee grounds vs haematemesis. old melaena or fresh or bright red. NSAIDS, anticoags, antiplatelet or alcohol? Hx of AAA. PR exam, HR, BP postural drop and signs of shock
- Glasgow Blatchford score - urea, Hb (sex) systolic BP,HR, melaena, syncope, liver disease, HF. GBS 1 low risk can be d/c
- U&E, FBC, LFT, INR and cross match
RBC if Hb <80. <90 + CVS
Variceal bleeding hb <70
Platelets if M50x01
Anticoag reversal with d/w endoscopist, haem. - Omeprazole 80mg IV bolus - 8mg/hr infusion until endoscopy
- Unstable bleed admit to 32 or ICU. NBM, IV fluids if high risk - call gastro OGD in 24/12 hours for variceal bleed. Stable admit gen med, routine OGD , stool chart, SBP monitoring if <100
VARICEAL BLEEDING- special terlipressin, ceftriaxone 1g 24hr , BP 90 SBP
- AFTER OGD
- omeprazole infusion, feeding as per risk,
- h pyori testing - carbon urea breath testing or faecal antigen testing (2 weeks after stopping ppi).
NSBB nadolol for secondary prophylaxis of variceal bleeding. Cont iv abx and terlipressin until bleeding controlled. Endoscopic ligation 1-4 week repitition
Areas for MI on ECG corresponding leads and artery
LAD occlusions
Septal MI: V1,2
Anterior : V3,4
Lateral: V5,V6, I AVL
RCA occlusion distal to RV :
Inferior MI: II, III and aVF
TIA investigations + management
Ix – FBC, U&E, glucose, lipids. CXR, Carotid USS +/- angiography , CT or difusion weighted MRI, ECHO for patent foramen ovale
Do the ABCD2 7 day risk of stroke score –looking at age, BP, Clinical features of stroke, lasting >60min>, diabetes. Depending on score urgent OP TIA clinic or observation in stroke unit
Management
Control CV risk – target 140/85, statins, control DM
Smoking cessation
Antiplatelet: aspirin 300mg daily or clopidogrel 75mg daily. Anticoagulation if cardiac embolic
Invasive management if Carotid USS shoes >70% stenosis and operative risk is good, 50-70 if risk very low. Should be within 2 weeks of first presentation.
Not for antiplatelets beforehand
Carotid stenting if not good for surgery
Alcohol withdrawal
- AUDIT C
- Bloods - FBC, LFT, INR
- Stat dose of pabrinex I pair IV
- Diazepam if well/ young, if >60 comorbid Lorazepam on lengthening schedule
- Wernickes - prophlaxis or treatment w ith pabrinex or thiamine 200mg IM daily
- Delirium tremens - IV diaz or loraz with consult reg + ICU
Pneumonia in hospital treatment vs CAP
In hospital
- if well augmentin 1.2 g IV Q8H for 1-2 days then po 625mg TDS for 3-4 days
Penicillin allergy - clindamycin 450mgIV Q8H 1-2 days + gentamicin 5mg/kg IV LBW daily
CAP
CURB 0-1 amoxicillin 500mg po TDS for 5 days
2-3 - amox + doxycycline 100mg po BD 5 day s
3-5 - augmentin 1.2 g IV Q8H + azithromycin 500mg po daily 5 days
If penicillin allergy
1 or 2 doxycycline 200mg po BD for 1 days + 4 days 100mg BD
3-5 clarithromycin 500mg IV BD
Vancomycin SE and monitoring requirements
SE - renal failure and intersitial nephritis, ototoxocity, neutropenia, pseumembranous collits
- Vancomycin prescribed using vanculator - based on gender, age, height, actual body weight, plasma Cr)
- Need plasma vancomyicin measurement within 24hrs of starting therapy or changing dosing, weekly for pt with stable renal function and dosing
Hypokalaemia- mild to 3, moderate 2.5-3, severe <2.5
ix, signs, treatment
Causes
- Decreased intake from starvation
- Mg depletion
- Mineralocorticoid excess - hyperaldosteronism
Increased loss
- diuretics/laxatives
- Skin, GI loss, Renal tubular disorders, endocrine - cushings, conns
Transcellular
- insulin/glucose, B- a, respiratory and metabolic alkalosis
Ix
1. Bloods - K+ , Mg, Ca , Phosphate
2. ECG - U waves, T wave flattening, ST depression –> VF/VT
3. Digoxin level
Management
1. replace Mg2 as facilitates more rapid correction of hypokalaemia
2. Non acute 10-20mmol /hr
3. life threatening - K+ 20mmol over 10 min
Mg2+ 10 mmol over 10 min
Hypomagnesmia - <0.75 mmol , sx at 0.5
ix, signs, treatment
Causes
- reduced intake: malabsorption, alcoholism, PPI
- increased loss: NG , D+V, diuretics, hypercalcemia, hyperaldosteronism, burns, acute pancreatitis
Ix
24hr urine >24mg renal wasting
fractional excretin of MG >4% renal wasting
Tissue magnesium level estimation - mg load test
Tx
Rapid IV bolus mg 2g in emergency
Oral mg 120mg TDS
correct other electrolyte abnormalities (hypok, hypoca.
K sparing diuretics for chronic renal mg wasting
Causes of shortened QT- what is short
Abnormal short if <350ms
- Hypercalcaemia - shortening of ST segment + osborne waves
- congenital short QT syndrome (tall peaked T waves, lone atrial fibrilation
-
Digoxin toxicity -(also downward sloping ST depression in lateral leads, widespread T wave flattening and inversion
Bundle branch blocks - L and R + causes
LBBB - V1 -W dominant S wave. V6 broad notched M shaped wave. I, AvL V5, V6 (lateral leads - show M shaped, notched, monophase or rS complex
causes- anterior MI, aortic stenosis, dig toxicity
RBBB - V1 -3 M shaped (RSR pattern QRS) and wide slurred S wave in lateral leads I,aVL, V5-6 (W)
causes - RVH, PE, RHD,
UTI treatment
Simple cystitis - nitrofurantoin MR 100mg po BD 5 days
Flank pain / tenderness /fever - Gentamicin 5mg/kg LWB IV daily 1-2 days then co-trimoxazole 960mg po BD for 5-6 days
IF catheter and flank pain - gent + amoxicillin 1g IV Q6H for 1-2 days then review sensitivities
hypocalcaemia
ix, signs, treatment, reasons for iv calcium
perioral numbness
paresthesias
muscle cramps
mild mental status changes (irritability)
seizures
tetany
collapse
to find cause: diet, drugs, symptoms specific to cause
laryngospasm
EXAMINATION
Chvostek sign (tapping facial nerve anterior to ear -> spasm of facial muscles)
Trousseau sign (inflate BP cuff -> trap median nerve -> carpal spasm)
hypotension
arrhythmias (long QT)
heart failure
signs specific to cause
Ix
Ca2+ (total and ionized)
PO43- Mg2+ PTH
ECG: prolongation of ST segment and QT interval -> VT
albumin
lipase (rule out pancreatitis)
U+E – renal failure, hyperkalaemia
CK and urate – rhabdomyolysis
Management
treat cause
proportional to severity
oral Ca2+
replace Mg2+
vitamin D
IV calcium (10mL gluconate = 2.3mmol = 93mg, 10mL chloride = 6.8mmol = 272mg)
indications for IV calcium therapy:
-> symptomatic hypocalcaemia
-> ionized Ca2+ <0.8mmol/L
-> hyperkalaemia
-> Ca2+ channel blocker OD
-> hypermagnesaemia
-> hypocalcaemia with high inotrope requirement
-> massive transfusion
-> post cardiopulmonary bypass
Definition of addison crisis + sx and treatment
In the setting of known adrenal insufficiency (cortisol) if existing cortisol replacement does not meet increased need eg. illness with fever, persistentd&v, trauma, surgery or childbirth.
Sx - sudden lower back, abdomenal pain, headache, d&v, dehydration, LBP, impaired consciousness
Treatment
100mg hydrocortisone IV or IM followed by rapid 0.9% saline. then maintain 200mg hydrocortisone/24 hours (cont IV infusion)
Omeprazole SE
GI disturbance. headache. Rarely hypomagnesaemia
How to interpret anticoagulation tests - PT/ INR, APTT, Thrombin time,
PT = prothrombin time. This measures the time taken to clot via the extrinsic pathway - factor 7, therefore mainly about overall clotting factor synthesis or consumption.
Warfarin is tested with INR
Affected by liver disease, DIC, vit k or warfarin
APTT - activated partial thromboplastin time - time for blood to clot via intrinsic pathway. Factor 8, 9,10 . Also shows up von wille as it pairs with f8.
TT - thrombin time - how fast fibrinogen is converted to fibrin. When prolonged - overall clotting factor synthesis or consumption.
