Therapeutic Drug Monitoring, Calcium, Enzymes and Cardiac Markers Flashcards
(39 cards)
1
Q
Phenytoin
- used to treat?
- signs of toxicity?
A
- Seizures
- Ataxia and nystagmus
2
Q
Phenytoin
- interactions and cautions?
- treatment?
A
- At high levels liver becomes saturated -> surge in blood levels
- Omit/ reduce dose
3
Q
Digoxin
- used to treat?
- signs of toxicity?
A
- Arrythmias
- Arrythmias, heart block, confusion, xanthophsia (seeing yellow)
4
Q
Digoxin
- Interactions and cautions?
- Treatment?
A
- Levels increased with hypokalaemia. Reduce dose in renal failure and in elderly
- Digibind AKA Digoxin immune Fab
5
Q
Lithium
- used to treat?
- Signs of toxicity?
A
- Mood disorders eg bipolar
- Tremor (early), lethargy, fits, arrhythmia, renal failure
6
Q
Lithium
- Interactions and cautions?
- Treatment?
A
- Excretion impaired by hyponatreamia, decreased renal function and diuretics
- Renal failure may need heamodialysis
7
Q
Gentamicin
- Used to treat?
- Signs of toxicity?
A
- Infection
- Tinnitus, deafness, nystagmus, renal failure
8
Q
Gentamicin
- Interactions and cautions?
- Treatment?
A
- Mostly use single daily dosing. Monitor peak and trough level before next dose
- Omit/ Reduce dose
9
Q
Theophyline
- Used to treat?
- Signs of toxicity?
A
- COPD, Asthma - Bronchodilator
- Arrythmias, anxiety, tremor convulsions
10
Q
Theophyline
- Interactions and cautions?
- Treatment?
A
- Variation in 1/2 life; e.g. 4hr for smokers, 8hrs for non smokers, 30hrs in liver disease. Level increased by erythromycin, cimetidine and phenytoin
- Omit/ Reduce dose
11
Q
Normal range for Calcium and body composition? (can’t think of the correct way of saying it)
A
- 2-2.6mmol/l
- 45% isonised (free- biologically active form)
- 50% bound to albumin, therefore affected by albumin level- use corrected calcium
12
Q
What are the two main hormones involved in calcium metabolism?
A
PTH
1,25 (OH)2D - Calcitriol
13
Q
PTH - Parathyroid Hormones - how does it have its effects?
A
- Increases tubular 1alpha hydroxylation of vitamin D (25(OH)D) leading to increased intestinal absorption via calbindin
- Mobilises calcium from bone
- Increase renal calcium reabsorption
- Increase renal phosphate excretion
14
Q
1,25 (OH)2D - Calcitriol -how does it have its effects?
A
- Increase calcium and phosphate absorption from the gut
- Bone remodelling
15
Q
Disorders of Calcium Balance
- Primary Hyperparathyroidism
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Increase in PTH (80% parathyroid adenoma)
- Ca = HIGH
- PO4 = LOW
- PTH = HIGH/NORM
- Alk Phos = HIGH/NORM
- Vit D = NORM
16
Q
Disorders of Calcium Balance
- Secondary Hyperparathyroidism
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Renal Osteodystrophy
- Ca = LOW/NORM
- PO4 = HIGH
- PTH = HIGH
- Alk Phos = HIGH
- Vit D = NORM
17
Q
Disorders of Calcium Balance
- Tertiary Hyperparathyroidism
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Autonomous PTH secretion post renal transplant
- Ca = HIGH
- PO4 = LOW
- PTH = HIGH
- Alk Phos = HIGH/NORM
- Vit D = NORM
18
Q
Disorders of Calcium Balance
- Hypoparathyroidism
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Low levels of PTH. Primary = DeGeorge Syndrome. Secondary = Post Thyroid Surgery
- Ca = LOW
- PO4 = HIGH
- PTH = LOW
- Alk Phos = LOW/NORM
- Vit D = NORM
19
Q
Disorders of Calcium Balance
- Rickets/ Osteomalacia
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Vitamin D deficiency
- Ca = LOW
- PO4 = LOW
- PTH = HIGH
- Alk Phos = HIGH
- Vit D = LOW
20
Q
Disorders of Calcium Balance
- Paget’s Disease
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Re-modelling of bone
- Ca = NORM
- PO4 = NORM
- PTH = NORM
- Alk Phos = HIGH
- Vit D = NORM
21
Q
Disorders of Calcium Balance
- Osteoporosis
- primary defect?
- Ca, PO4, PTH, Alk Phos, Vit D levels?
A
- Bone loss
- Ca = NORM
- PO4 = NORM
- PTH = NORM
- Alk Phos = NORM
- Vit D = NORM
22
Q
Causes of Hypercalcaemia with High Albumin?
A
Urea high = Dehydration
Urea normal = Cuffed (left the tourniquet on too long when taking blood)
23
Q
Causes of Hypercalcaemia with Low/Norm Albumin and Low phosphate?
A
Primary or Tertiary hyperparathyroidism - confirm with ++ PTH
24
Q
Causes of Hypercalcaemia with Low/Norm Albumin and High phosphate?
A
- High ALP (increased bone turnover) - Bone metastasis, Thyrotoxicosis, Sarcoidosis (increased 1alpha OH)
- Normal ALP - Myeloma, Excess Vit D, Sarcoid, Milk alkali syndrome ( + high HCO3)
25
Symptoms of Hypercalcaemia?
```
Stones (renal)
Bones (pain)
Groans (psych)
Moans (abdo pain)
Polyuria
Muscle Weakness
```
26
Treatment for Hypercalcaemia?
Correct dehydration
Bisphosphonates
Correct cause e.g. chemo for cancer
27
Causes of hypocalcaemia with High Phosphate?
Chronic Kidney Disease
Hypoparathyroidism (inc post thyroid surgery)
Pseudohypoparathyroidism
Hypomagnesaemia
28
Causes of hypocalcaemia with Norm/Low Phosphate?
Osteomalacia
Acute pancreatitis
Over hydration
Respiratory alkalosis (low ionised/active Ca)
29
Symptoms of Hypocalcaemia?
Perioral paraesthesia
carpopedal spasm
neuromuscular excitability
(Trousseau's and Chvostek's sign)
30
Treatment for Hypocalcaemia?
Mild - Give calcium
Chronic Kidney Disease - Alfacalcidol
Severe - 10% calcium gluconate IV
31
Risk Factors for Renal Stones
Dehydration , abnormal urine pH (e.g. meat intake, renal tubular acidosis), increased excretion of stone constituents, urine infection (treat infection), anatomical abnormalities
32
Renal Stones - Calcium Stones
- due to?
- preventative management?
most patients are normocalcaemic
Results from
-Hyperoxaluria - Increased intake, absorption etc
-Hyercalciuria - increased intake, renal leak
Preventative management - avoid dehydration, reduce oxalate intake, maintain Ca intake, thiazides -> hypocalciuric, citrate (alkalinise urine)
33
Investigations for recurrent Renal Stones
- Serum - Cr, Bicarbonate, Ca, Phosphate, Urate, PTH (if hypercalcaemic)
- Stone analysis
- Spot urine
34
6 different stone compositions, Frequency and X ray appearance
- Calcium mixed - 45% - Radio-opaque
- Calcium oxalate - 35% - Radio-opaque
- Calcium phosphate - 1% - Radio-opaque
- Tripple phosphate "Struvite" - 10% - Radio-opaque "staghorn calculi" (branching calcific densities overlying the renal outline
- Uric acid - 5% - Radiolucent
- Cysteine - 1-2% - Radiolucent
35
Amylase levels in pancreatitis?
High serum levels in acute pancreatitis - usually >10x upper limit of normal (normal serum amylase test - 40-140U/L
36
Creatine Kinase is a marker of? Raised levels due to?
CK is a Marker of muscle damage (CK-MM = Skeletal muscle, CK-MB (1&2) = cardiac muscle)
- raised levels due to
- Physiological - Afro-Caribbean (5x upper limit of normal)
- Pathological - Duchenne Muscular Dystrophy (>10x Upper limit of normal), MI (>10xULN), Statin related myopathy, Rhabdomyolysis
37
Alkaline Phosphatase - Causes of raised levels?
Present in high concentrations in liver, bone, intestine and placenta
-causes of raised ALP :-
-Physiological - Preganacy (third trimester), Childhood (during growth spurt)
- Pathological
->5xULN = Bone (Pagets, osteomalacia), Liver (Cholestasis, Cirrhosis)
-
38
Troponin (NOT an enzyme) - Biomarker for?
Myocardial injury biomarker
| Measure at 6 hours and then at 12 hours post onset of chest pain, remains elevated for 3-10 days
39
Diagnostic Criteria for Acute MI
1) Typical rise and gradual fall (troponin) or more rapid rise and fall (CK-MB) with at least one of the following...
- ischemic symptoms
- pathological Q waves on the ECG
- ECG changes indicative of schema
- Coronary artery intervention
2) Pathological findings of an acute MI
