thr patient Flashcards

Question

role of placenta

Answer 1

nutrient uptake, waste elimination & gas exchange

Answer 2

Lipid soluble, unionised medicines cross placenta quicker

Answer 3

Medicines should only be prescribed when BENEFITS to the mother > RISK to the fetus * Simple Rules: Preferably use agents extensively used before Use lowest effective dose * To aid compliance all risks and benefits should be discussed with mothers for each medication and their importance.

Answer 4

Trimester/ number of weeks? Past pregnancies? Previous exposure? Necessity for therapy? Duration of therapy Drug properties i.e half life, Teratogenicity risk

Answer 5

Folic acid supplementation – Essential vitamin to ensure neural tube closure – Low risk; 400microgram OD pre conception to week12 – High risk; 5mg OD before conception to week12 * Vitamin D (10mcg per day) * No Alcohol government advice * Vitamin A (restrict to 700mcg) * Vitamin K supplementation – May be required

Answer 6

Timing of exposure – Dose – Maternal Disease – Genetic Susceptibility * Teratogenicity can be dose dependent. * Can get incidence of spontaneous malformations in normal population.

Answer 7

Initiate breastfeeding within 1st hour of life and continue exclusively for first 6 months of life * Breast fed “on demand” – eg led by the baby, not at specific times * No bottles or dummys should be used to avoid latching on issues

Answer 8

Contains secretory IgA (sustained benefit if BF >13wk) * Child (seen if BF >13weeks) – Reduces risk of infection * GI (diarrhoea), UTI, otitis media, LRTI, NEC – Increased cognitive development – Protection against development of atopic-disease – Reduction in childhood leukaemia's – Reduction in hypertension, diabetes and obesity

Answer 9

Reduction in risk of pre-menopausal breast cancer, ovarian cancer and hip fractures.

Answer 10

Not enough breast milk – Sore/cracked nipples – Breast engorgement – Blocked duct / mastitis – Latching problems – Painful, messy and tiring – Difficult to establish – Breast fed babies wake more often during the night – More difficult for mothers to return to work – Mother may need to modify her diet – Privacy/ public perceptions

Answer 11

Formula milk not a true replica * Breast milk complex, contains antibodies, enzymes and hormones. * Colostrum (yellow milk) high in immunoglobulin's * Newborn infants have high calorific and fluid requirements – Av fluid 150ml/kg/day – Calories 110kcal/kg/day * 40% of energy comes from carbohydrate (mainly lactose) and 50% from fat.

Answer 12

Oral bioavailability eg LMWH’s, insulin * Plasma Protein Binding eg ibuprofen * Milk:Plasma ratios – lower the value the smaller the transfer eg sertraline = 0.89, iodine = 26 * MW - >MW have lower oral bioavailability * 1st pass metabolism eg morphine * Relative infant dose – Less than 10% * Half life – affect infants excretion

Answer 13

Other factors – Age of baby – drug clearance – Volume of feeds – Frequency of feeds * Generally manufacturers do not gain a licence for drugs in breastfeeding so are cautious and recommend against it. * Due to ethics there are no large randomised studies on drugs in breast feeding.

Answer 14

Drug used with caution or contraindicated * Safe as present in milk in amounts too small to be harmful to infant * Safe as present in milk in significant amounts but not known to be harmful.

Answer 15

Medicines considered UNSAFE in breast feeding ◦ Indomethacin ◦ Clindamycin ◦ Mesalazine ◦ Amiodarone ◦ Tetracyclines (long-term) ◦ Statins ◦ Codeine/Morphine

Answer 16

Atenolol  Diuretics ➔ Case report of bradycardia, cyanosis and hypothermia ➔May suppress lactation = diuretics

Answer 17

Penicillins  Erythromycin  Cefalexin  Ibuprofen  Diclofenac  Senna  Lactulose  Loperamide

Answer 18

Oestrogens have a significant effect on suppressing milk production – Can use POP * Dopamine receptor agonists: suppress lactation * Dopamine antagonist: Promote lactation

Answer 19

If not necessary avoid drug use – Limit OTC product use * Avoid known toxic drugs * Generally if drug is licensed in infant it may be ok * Neonates at greatest risk * Monitor infants for side effects * Avoid long acting formulations * Avoid new medicines – Limited data * Most important is Benefit/Risk ratio

Answer 20

SPC Clarityn available at eMC – “Loratadine is excreted in breast milk. Therefore, the use of Clarityn Allergy Tablets is not recommended in breast-feeding women.” * BNF – “Most antihistamines are present in breast milk in varying amounts; although not known to be harmful, most manufacturers advise avoiding their use in mothers who are breast- feeding.” decicion from other sources: The amount excreted in to milk is low. * No harm has been reported from use during breastfeeding. * Considered to be compatible.

Answer 21

Important to understand principles of prescribing in pregnancy and breast feeding * Ultimately  Understand stages of pregnancy and how it affects drug therapy  Know the benefits of breastfeeding ◦ Awareness on organisations and government message ◦ How breastfeeding affects drug therapy choice  Overall be able to apply knowledge and use appropriate references to specific patients and make evidence based decisions on drug therapy in pregnancy and lactation

Answer 22

infant / toddler

Answer 23

adolescent

Answer 24

Movement – 0-3mths: Lift head. – 6-8mths: Sit. – 10-18mths: Walk unaided (mostly)

Answer 25

6mths: Cooing(baby noises). -12mths: First words.

Answer 26

2wks: Recognise parents by sight. – 6mths: Able to see fully.

Answer 27

They are NOT small adults * Large varied population. * Significant pharmacokinetic (ADME) and pharmacodynamic differences between child age bands and with adults.

Answer 28

Gastrointestinal tract changes * Neonates ⇑pH (6-8) – ⇓ bioavailability of acidic medicines (phenobarbital, phenytoin). – ⇑ bioavailability of weakly basic drugs (penicillin, erythromycin). * Gastric emptying and intestinal motility decreased in neonates – Normal intestinal function by 4-6mths. – Normal gastric emptying and pH by 3yrs.

Answer 29

Routes of administration: * I.M. Injection: – Painful and distressing for children. – Rate and extent of absorption depends upon blood flow to the muscle. * Rectal: – May be slow and unpredictable. – Useful if vomiting or NBM. Neonatal liver is immature. * Can't metabolise drugs as efficiently: E.g. explains “gray baby syndrome with chloramphenicol * Renal clearance can take 8-12 months to develop to adult values * Can result in half lives and higher plasma concentrations of hepatic and renally excreted drugs: Phenytoin, Analgesics, Cardiac glycosides * Useful for phenobarbitone- only needs 1 loading dose as remains in circulation for longer. * However, vancomycin and gentamicin have narrow therapeutic index- reduced frequency of doses to avoid toxicity

Answer 30

1. Neonates have thinner stratum corneum. 2. ⇑ Ratio of surface area : weight

Answer 31

Injection into bone. ‒ Usually tibial injection.

Answer 32

Guaranteed method of drug delivery. * Preferable in neonatal period: - Clinical condition - Prematurity - Gastric instability * Caution with rates of infusion and fluid volumes as different size to an adult: ‒ Term neonates should receive 60-150ml/kg/day of fluid. ‒ Average 3 year old (15kg) can have 1250ml/day

Answer 33

Water = high in the neonate and slowly reduces to 60% in children Body Fat = low in premature babies ~ 2%, high in children up to 1yr ~30%, reduced back to adult value ~18% take into account water soluble drugs

Answer 34

Protein is altered in neonates and young children; gets reduced * Potentially more free drug available. * Therefore; need to reduce doses of highly protein bound drugs e.g. phenytoin, sodium valproate, furosemide.

Answer 35

Talking about the interaction between drug and receptor. * Less is known about this. * May explain increased hepatic toxicity seen in infants on sodium valproate

Answer 36

Haematological changes – Hb and neutrophil counts are lower in younger children. – Lymphocyte counts have a higher mean in younger children. – Platelets decreased in first few months, normalised by 6 months. * NB labs have own standard values so important to use these BP HR respiratory canges

Answer 37

Dose calculations based on: ‒ Weight ‒ Body Surface Area  BSA ‒ Nomograms available ‒ BSA = √ (weight x height / 3600) ‒ Used mainly for chemotherapy and other medicines like IV aciclovir.  May need to use ideal body weight in obesity (better to underdose)

Answer 38

Most licensed oral medicines are tablets Child friendly medicines * Tablet crushing is common. * Don’t crush MR, LA or cytotoxic preparations. * Can disperse in water and take fractions of dose- careful as not all meds are compatible. Tablet cutting is also common. * Can split tablets. * Caution with unscored tablets. * Should not split MR, EC or cytotoxic meds.

Answer 39

Suppositories: ‒ Uniformity of dose uncertain. ‒ Split lengthways- for comfort. * Patches: ‒ Can cut matrix patches. ‒ Cannot cut reservoir patches * Liquids: ‒ Formulations can contain E numbers, ethanol, sweeteners, preservatives

Answer 40

All medicines must have a product license or marketing authorisation. * Many granted a license for adult use have NOT been tested in children. * Things have changed: – EU paediatric regulation came into force 2007 to help: >Improve health of children >Facilitate development and availability of medicines for children >Ensure medicines are high quality, ethically researched and authorised appropriately >Improve the availability of information on the use of medicines – Manufacturers must provide paediatric information when applying for a marketing authorisation (USA, Europe) known as PUMA

Answer 41

Unlicensed or off-label drugs are received by: * 90% babies in neonatal ICU. * 70% patients on PICU. * 67% children in European hospitals. * 11% children treated by GPs.

Answer 42

MHRA Unlicensed medicines have no marketing authorisation and are used when no appropriate licensed preparations are suitable/available

Answer 43

Extemporaneous dispensing: ‒ Crushing tablets or opening capsules.  ‘Specials’: ‒ Use of a unlicensed product from a specials manufacturer. E.g. Clonazepam suspension.  Specialist import: ‒ Import licensed medicine from another country.  ‘Named patient’ supply: ‒ Pharmaceutical companies supply for specific patient.

Answer 44

Off-Label” medicines have a marketing authorisation but are used outside their product license

Answer 45

Lower or higher dose. ‒ Patient age. ‒ Indication. ‒ Route of administration. ‒ Contraindications.

Answer 46

Regarding the use of unlicensed and off label medicines in paediatrics, the RCPCH and NPPG advise: – Informed use of UL or OL medicines in paediatrics is necessary. – It is not necessary to obtain consent from parents/patients to administer such medicines beyond those steps taken for licensed medicines.

Answer 47

Currently there are significant issues sourcing medications in the UK. * Not just in paediatrics, but adults too. * Issues around common medicines and formulations used in paediatrics. * Reasons include: * COVID and its aftermath * Brexit * Wars in Ukraine and other countries * We have to use more UL/off label medications as a result.

Answer 48

Children are more vulnerable to errors with medication and have reduced reserve to respond to incorrect dosing. * More complex calculations. * Suitability of formulations available. * Different diseases. * 10 and 100 fold dose errors are not uncommon. * Variable weight.

Answer 49

Check & record allergies and reaction.  Confirm correct weight.  Weight based dose should  not exceed adult dose!  Prescription must be legible.  Each step of calculations should be written out and double checked

Answer 50

BNFC.  National standard text.  Monographs as per adult book.  Info on use of a medicine in renal and liver impairment, pregnancy or breast feeding within monograph medicines complete

Answer 51

Neonatal Formulary. * Very comprehensive text for doses in neonates. * Evelina (Guy's and St Thomas' paeds formulary) * Available via app (available to all), or Clinibee- login required. Use with caution as undergraduate Medicines for Children. * Preceded and predates BNFC Lexi-Comp Pediatric Dosage Handbook. * Comprehensive text with detailed drug monographs. * American- FDA licensing, their dosing regimes. * Useful supplementary information in appendices.

thr patient Flashcards

(78 cards)