Chapter 9: Blood and nutrition Flashcards Preview

Pre Reg 2021 U > Chapter 9: Blood and nutrition > Flashcards

Flashcards in Chapter 9: Blood and nutrition Deck (85)
Loading flashcards...
1
Q

What are the MHRA warnings associated with epoetins?

A
  • Risk of severe cutaneous adverse reactions including SJS. - Overcorrection of [haemoglobin] may ^risk of death and serious CV events. CKD or chemo pts should not receive this unless symptoms of anaemia are present - Unexplained excess mortality and ^risk of tumour progression in patients with anaemia associated with cancer who have been treated with erythropoietin
2
Q

What are the main side effects of epoetins?

A
  • Severe skin reactions and stop treatment and seek medical attention if they develop a rash (which often follow flu-like symptoms) - Hypertensive crisis with encepathalopathy and tonic clonic seizures- Pure red cell aplasia
3
Q

What are epoetins used for?

A

Symptomatic anaemia in CKD or chemo patients

4
Q

The daily oral dose of elemental iron for iron-deficiency anaemia should be what?

A

100-200mg

5
Q

Are modified release iron preparations recommended in anaemias?

A

No - have no therapeutic advantage

6
Q

In what situations would you opt for IV iron over oral iron?

A
Oral therapy is unsuccessful; 
Intolerable of oral iron
Continuing blood loss 
Malabsorption
CKD patients on dialysis
7
Q

What are the IV forms of iron?

A

Iron dextran
Iron sucrose
Ferric carboxymaltose
Iron isomaltoside

8
Q

Does IV iron work more quickly than oral iron?

A

Parenteral iron does not produce a faster haemoglobin response than oral iron provided that the oral iron is taken reliably and is absorbed adequately.

Exception: pts with severe renal failure receiving haemodialysis

9
Q

IV iron does not work more quickly than oral iron except in what group of patients?

A

Patients with severe renal failure receiving haemodialysis

10
Q

What is the MHRA advice surrounding injectable iron?

A

Serious hypersensitivity reactions including anaphylaxis Pts should be monitored for such signs for 30 minutes after administration Not recommended 1st trim. of preg. and only in 2nd and 3rd if vital

11
Q

When should iron for iron deficiency anaemia be stopped?

A

3 months after haemoglobin is in the normal range

12
Q

Are iron tablets best absorbed with or without food?

A

Without foodHowever because of the GI side effects, they can be taken with food

13
Q

What are the main side effects of iron?

A

Constipation and diarrhoeaGI upsetDarkened stools

14
Q

Most megaloblastic anaemias result from a deficiency of what?

A

Either vitamin B12 or folate It is important to establish which deficiency before treatment but in an emergency can give both

15
Q

What is pernicious anaemia?

A

An autoimmune gastritis causing malabsorption of vitamin B12

16
Q

What is the choice of therapy for vitamin B12 replacement?

A

Hydroxocobalamin - initiated with frequent IM injections and then every 3 months(used to be cyanocobalamin however hydroxocobalamin lasts longer in the body)

17
Q

Why should undiagnosed megabloblastic anaemia not be treated with folic acid alone?

A

May precipitate neuropathyIf undiagnosed and needs to be given, always give vitamin B12 as well

18
Q

What can be the causes of folate-deficient megaloblastic anaemia?

A

Poor nutritionPregnancyAntiepileptic drugs

19
Q

How do you treat folate-deficient megaloblastic anaemia and how long for?

A

Daily folic acid for 4 months(Folic acid has few indications for long-term therapy since most causes of folate deficiency are self-limiting or will yield to a short course of treatment)

20
Q

Why should folic acid never be given alone in pernicious anaemia?

A

Can cause compression of spinal cord

21
Q

Haemochromatosis is associated with an overload of what?

A

IronBuilt up over several years

22
Q

How do you manage haemochromatosis (result of iron overload)?

A

Venesection (removal of blood)If contraindicated- long-term administration of the iron chelating compound Desferrioxamine mesilate - Vit C aids iron chelation started 1 month after desferrioxamine, taken daily, not with food.

23
Q

What drug inhibits platelet formation and is used for thrombocythaemia (when too many platelets are produced in the bone marrow)?

A

Anagrelide

24
Q

What is used in sickle cell anaemia to reduce the frequency of crises and need for blood transfusions?

A

Hydroxycarbamide

25
Q

How do you manage severe acute hyperkalaemia?

A

1st = Calcium gluconate 10% slow IV injection titrated to ECG to temporarily protect against myocardial excitability2nd = Soluble insulin IV injection 5-10u with 50 mL glucose 50% over 5-15 min, reduces serum-[K]; repeated if necessary or continuous infusion instituted3rd = Salbutamol nebulised or slow IV injection [unlicensed] may also reduce plasma-potassium concentrationThe correction of causal or compounding acidosis with Na bicarbonate infusion should be considered (important: prep of sodium bicarbonate and calcium salts should not be administered in the same line—risk of precipitation). Drugs that exacerbate hyperkalaemia should be stopped as appropriate.

26
Q

What is classed as acute severe hyperkalaemia?

A

> 6.5 mmol/L or presence of ECG changes

27
Q

What is classed as hypokalaemia?

A

< 3.5 mmol/L

28
Q

How do you manage hypokalaemia?

A

Potassium chloride OrPotassium bicarbonate with potassium acid tartrate.

29
Q

Chronic hyponatraemia from inappropriate secretion of ADH should ideally be managed by what?

A

Fluid restriction

30
Q

What is Hartmann’s solution?

A

Compound sodium lactate

31
Q

How is severe hypercalcaemia managed?

A

Dehydration should be corrected with IV NaClDrugs that promote hypercalcaemia e.g. thiazides and Vitamin D should be stoppedPharmacological management includes bisphosphonates, corticosteroids, calcitonin

32
Q

When treating hypokalaemia, why shouldn’t you include glucose infusions?

A

That can cause a further decrease in plasma potassium concentrations

33
Q

What can be given for severe metabolic acidosis?

A

IV sodium bicarbonate

34
Q

What can be given for chronic acidotic states?

A

Oral sodium bicarbonate

35
Q

Compared to crystalloid solution, would a larger or smaller amount of colloid solution be required for fluid resuscitation?

A

Smaller amount would be required of colloid

36
Q

True or false: In osteoporosis, a calcium intake which is double the recommended amount reduces the rate of bone loss.

A

True

37
Q

What is given in severe acute hypocalcaemia/hypocalcaemic tetany?

A

Slow IV calcium gluconate 10%

38
Q

Why should calcium gluconate IV be given slowly?

A

If given too rapidly, risk of arrhythmias

39
Q

What is cinacalcet used for?

A

Hyperparathyroidism and hypercalcaemia in parathyroid carcinomaReduces parathyroid hormone which leads to a decrease in serum calcium concentration

40
Q

Calcium carbonate is used for what two indications?

A

Calcium deficiency Phosphate binding in renal failure

41
Q

Aluminium hydroxide can be used for the treatment of what in renal failure?

A

Hyperphosphataemia

42
Q

What is sevelamer used for?

A

Phosphate binder for CKD patients including those on dialysis

43
Q

How do you manage hypercalciuria?

A

Find the underlying reasonIncrease fluid intake and give bendroflumethiazideMOA of thiazides is to decrease Na reabsorption and therefore decreased fluid reabsorption; this directly causes decreased levels of circulating sodium. Thiazides increase the uptake of calcium in the distal tubules, to moderately reduce urinary calcium.

44
Q

What is Wilson’s disease?

A

Genetic disorder causing build up of copper in body tissues e.g. brain

45
Q

How do you manage Wilson’s Disease?

A

Zinc acetate as it prevents the absorption of copperChelating agents are given for the first 2-3 weeks as well as zinc as zinc has a slower onset of action

46
Q

Vitamin A deficiency is associated with what?

A

Occular defects

47
Q

_______ is what vitamin?ThiamineRiboflavinPyridoxineRetinol

A

B1 - ThiamineB2 - RiboflavinB6 - PyridoxineA - Retinol

48
Q

Hypocalcaemia effects

A

convulsions, arrhythmias, numbness<= Ca salts

49
Q

Severe Vitamin B deficiency can lead to what?

A

Wernicke’s encephalopathy and Korsakoff’s psychosis

50
Q

Hypercalcaemia effects

A

bone pain, stones, psychiatric issues<= cincalcet

51
Q

Pyridoxine may be needed in patients taking what drugs?

A

Isoniazid therapy or penicillamine treatment in Wilson’s disease

52
Q

Penicillamine is what kind of drug?

A

Chelating agent used for e.g. Wilson’s Disease, RA

53
Q

Vitamin C deficiency can result in what condition?

A

Scurvy

54
Q

What are the fat soluble vitamins?

A

ADEK

55
Q

What are the water soluble vitamins?

A

B and C

56
Q

Hypomagnesia effects

A

arrhythmias, hypokalaemia, hypocalcaemia<= Mg salts

57
Q

Vitamin D deficiency can result in what condition?

A

Rickets

58
Q

In renal patients, why is alfacalcidol and calcitrol more appropriate for Vitamin D deficiency treatment over other Vitamin D replacement?

A

Vitamin D requires hydroxylation by the kidney to its active form, therefore the hydroxylated derivatives alfacalcidol or calcitriol should be prescribed if patients with severe renal impairment require vitamin D

59
Q

If Vitamin D replacement is needed in severe renal impairment, what are the most appropriate to prescribe?

A

Alfacalcidol Calcitriol

60
Q

What is the water soluble Vitamin K preparation called?

A

Menadiol

61
Q

What is the MHRA advice surrounding IV thiamine?

A

Risk of serious allergic reaction Should be given over 30 mins Facilities to treat anaphylaxis should be close by

62
Q

Calcichew D3 is used for what?

A

Prevention + treatment of Vitamin D and Ca deficiency

63
Q

What is cholecalciferol used for?

A

Prevention and treatment of Vitamin D deficiency

64
Q

When would the higher dose of 5mg folic acid be recommended in pregnancy?

A

High risk of neural tube defects:EpilepsyDiabetesSickle cell Previous infant with neural tube defect e.g. spina bifidaOtherwise the dose would be 400mcg folic acid daily

65
Q

What is a Coombs test?

A

Test for autoimmune hemolytic anaemiaMethyldopa can cause a positive test result

66
Q

What is the treatment regimen for hydroxocobalamin in the treatment of pernicious anaemia (without neurological involvement)?What route?

A

IM injectionInitially 1 mg 3 times a week for 2 weeks, then 1 mg every 2–3 months.If neurological involvement- this would be 1mg on alternate days until improvement

67
Q

Iron absorption is impaired if having what foods/drinks?

A

TeaMilkEggs

68
Q

Rise in haemoglobin concentration takes aboutA. 2- 3 weeksB. 3- 4 weeksC. 1- 2 weeksD. 1 - 2 months

A

B 3-4 weeksRise in haemoglobin concentration takes about 3-4 weeks, treatment should be continued for a further 3 months to replenish the iron stores.

69
Q

Parenteral iron may have serious hypersensitivity reactions. Incidents of anaphylaxis have been reported. In the event of a reaction, treatment should be

A

STOPPED IMMEDIATELY

70
Q

drugs that may cause hypokalaemia (serum potassium concentration below 3.5 mmol/L)

A

Laxatives (excessive use)Diuretics^dose beta 2 agonistsTheophylline^dose penicillinsGentamicinAmphotericinEchinocandin antifungalsHigh dose insulinCorticosteroidsCisplatinSodium bicarbonateParecoxib

71
Q

Medicines known to increase serum potassium levels

A
  1. Reduction of K renal excretion due to hypoaldosteronism:Aldosterone antagonists: Spironolactone, eplerenoneACEI: Captopril, enalapril, lisinoprilARB: Candesartan, losartanNSAIDs: Ibuprofen, naproxen, diclofenac, meloxicamHeparins: Enoxaparin sodiumImmunosuppressive drugs: Cyclosporin, tacrolimus2. Reduction of potassium passive renal excretion K-sparing diuretics other than aldosterone antagonists: Amiloride, triamtereneAnti-infective drugs: Trimethoprim, pentamidine3. Reduction of K cellular transport Beta-blockers: Proprano, ateno, metoprolol, bisoprololCardiac glycosides: DigoxinMood stabiliser: Lithium4. Excess of potassium supply; salts; K chloride5. Unknown mechanism; Epoetin alfa, epoetin beta
72
Q

Idiopathic thrombocytopenic purpura

A

Children@ self limitingAdults: treat with corticosteroid (pred) gradually reducing dose over several weeksIf ineffective to achieve platelet count or relapse from reducing corticosteroid; splenectomy considered

73
Q

Hyperphosphatemia imbalance effectsmeds to treat?

A

Hyper (ectopic calcification, hyperparathyroidism)aluminium hydroxide, Phosex, sevlamer

74
Q

Hypophosphatemia imbalance effectsmeds to treat?

A

Hypo (weak muscles, mental issues, blood disorder)phosphate salts

75
Q

Compensation for potassium loss is especially necessary

A
  • in those taking digoxin or anti-arrhythmic drugs, where potassium depletion may induce arrhythmias;- in patients in whom 2ndaryhyperaldosteronism occurs, e.g. renal artery stenosis, cirrhosis of the liver, the nephrotic syndrome, and severe heart failure;- in patients with excessive losses of K in the faeces, e.g. chronic diarrhoea associated with intestinal malabsorption or laxative abuse.- elderly; frequently take inadequate amounts of potassium in the diet- long-term administration of drugs known to induce potassium loss (e.g. corticosteroids) long-term administration of drugs known to induce potassium loss (e.g. corticosteroids)
76
Q

Are potassium supplements required with small doses of diuretics to treat HTN?Are potassium supplements recommended for prevention of hypokalaemia due to diuretics?

A

Potassium supplements are seldom required with the small doses of diuretics given to treat hypertension; K-sparing diuretics (rather than supplements) are recommended for prevention of hypokalaemia due to diuretics such as furosemide or the thiazides when these are given to eliminate oedema.K salts cause n+v and poor compliance is a major limitation to their effectiveness; when appropriate, potassium-sparing diuretics are preferable.

77
Q

Mild hyperkalaemia

A

Ion-exchange resins may be used to remove excess potassium in mild hyperkalaemia or in moderate hyperkalaemia when there are no ECG changes.

78
Q

Oral rehydration therapy (ORT)

A

diarrhoea - most important indication for fluid and electrolyte replacementRehydration should be rapid over 3-4 hrs (except in hypernatraemic dehydration; slowly over 12 hours). Reassess after initial rehydration; if still dehydrated rapid fluid replacement should continue.Once rehydration is complete further dehydration is prevented by encouraging the patient to drink normal volumes of fluid and by replacing continuing losses with an oral rehydration solution; in infants, BF or formula feeds should be offered between oral rehydration drinks.

79
Q

hypokalaemia infusions

A

Potassium overdose can be fatal. Ready-mixed infusion solutions containing potassium should be used where possible. Potassium chloride solution for infusion must be given by slow intravenous infusion, under ECG control, ensuring adequate urine flow and with careful monitoring of electrolytes.Rapid infusion can be toxic to the heart; cardiacarrhythmias. Manufacturer recommendation is that the infusion rate should not exceed 20 mmol potassium per hour. A higher concentration and higher infusion rate may be given in severe potassium depletion under specialistsupervision.

80
Q

Hyperkalaemia effectsHypokalaemia effects

A

Fatigue, numbness, tingling, nausea or vomiting, trouble breathing, chest pain, irregular heart beatconstipation, irregular heartbeat, fatigue, muscledamage, muscle spasms, tingling, numbness

81
Q

drugs hyper Kdrugs hypo K

A

ACE inhibitors; potassium supplements; NSAIDs; heparins; spironolactone; amilorideDiuretics; beta-2 agonists, insulin; corticosteroids

82
Q

Hyper Na- symp- drugs- tx

A

Symptoms: dehydration, thirst, osmotic damage of cells (confusion, muscle twitching or spasms, seizures)Causative drugsCorticosteroids; IV abx with Na; oral contraceptive; sodium bicarbonateTreatmentCorrection of the relative water deficit. If IV, administered via dextrose or saline infusion. Rapid correction can lead to cerebral oedema.

83
Q

Hypo Na- symp- drugs- tx

A

Symptomsn+v, headache, confusion, fatigue, loss of appetite, irritability, osmotic damage of cells (confusion, muscle twitching or spasms, seizures)Causative drugsAnti-depressants; desmopressin; carbamazepine; diuretics; lithiumTreatmentHypovolemia: IV salineEuvolemic: fluid restriction & remove stimuli for ADHHypervolemic: address underlying heart or liver failure

84
Q

Pyridoxne dose

A

Prolonged use of pyridoxine in a dose of 10 mg daily is considered safe but the long-term use of pyridoxine in a dose of 200 mg or more daily has been associated with neuropathy.

85
Q

IV Thiamine

A

Rare risk of potentially serious allergic ADR, the CHM has recommended that:• This should not prevent the use of parenteral thiamine in patients where this route of administration is required, particularly in patients at risk of Wernicke-Korsakoff syndrome where treatment with thiamine is essential;• IV administration should be by infusion over 30 min;• Facilities for treating anaphylaxis (including resuscitation facilities) should be available when parenteral thiamine is administered