cystic fibrosis, lung cancer and sleep apnoea

Question 1

what is cystic fibrosis

Answer 1

an inherited disorder

• CFTR gene = chromosome 7
• is a recessive gene so both parents have to have it
• 1 in 4 children are affected, 2 of the remaining 3 are carriers, 1 is healthy

Question 2

how common is cystic fibrosis

Answer 2

• 1 in 25 of population are carriers = high chance of someone having gene
• 1 in 2500 births has CF to some extent = extent depends on how expressed gene is
• cariers can still have side effects of CF

Question 3

does CF always show up

Answer 3

no, may not show up in smaller cases

Question 4

where is the defect in CF

Answer 4

• inherited defect in cel chloride channels
• Cl channels regulate a variety of things in the cell
• problem means that they produce excess mucus that is like glue and very sticky
• any surface in the body where mucus is produced is now coated in a thick layer of slime so the normal function doesn’t work anymore

Question 5

what organs are mainly affected by CF

Answer 5

lung and pancreas

Question 6

what happened if you had CF in 1930’s

Answer 6

• got respiratory infections and didn’t have antibiotics to clear bacteria and debris so got pneumonia easier
• life expectancy a few months

Question 7

what happens if you have Cf now

Answer 7

• better understanding of the disease
• now have physio and antibiotics
• things are still improving = difficult as disease is multifactorial
• life expectancy around 31 years = get eventual lung failure so lungs don’t function

Question 8

what is CF characterised by

Answer 8

• lung congestion and infection and malabsorption of nutrients by the pancreas
• mucus blocks airway and you get infection behind it
• airways should be like a sponge but in CF it is all blocked
• get emphysema and can’t clear infection

Question 9

how is CF diagnosed

Answer 9

• perinatal testing
  = all children now screened at birth
  = Guthrie test - needle prick test on heel of foot to get a little blood to do testing
• sweat test
  = measures salt content of sweat - more salt in Cf patients
  = for people who missed perinatal and is used to confirm CF diagnosis

Question 10

what are the main symptoms of CF

Answer 10

• troublesome cough
• repeated chest infections = from unusual pathogens that don’t normally cause problems
• prolonged diarrhoea = don’t have ability to digest fat as pancreas is blocked by mucus, patients were advised to eat lots of carbs for energy
• poor weight gain

Question 11

what are the pathogens that cause CF chest infections

Answer 11

• Pseudomonas

- Stophylococci

Question 12

what are some other symptoms of CF

Answer 12

• liver dysfunction in some patients
• prone to osteoporosis = not absorbing nutrient they need
• diabetes symptoms = prolonged pancreas disease
• reduced fertility = mainly male, have thick mucus

Question 13

what is the treatment for CF

Answer 13

• physiotherapy
• medication
• exercise
• transplantation
• gene therapy?

Question 14

how does physiotherapy treat CF

Answer 14

• used to help remove mucus secretions from the lungs = aim of draining mucus into big airways to clear
• performed at home by parents = 10-60 mins a day
• involves moving child around to get different parts of lungs cleared

Question 15

what medications are used for CF treatment

Answer 15

• lungs
  = bronchodilators to open airways
  = antibiotics to reduce chest infection frequency - however if use these all the time will increase resistance so try to limit use
  = steroids to reduce airway inflammation
  = DNase to breakdown mucus
• digestive system
  = pancreatic enzyme replacement - Creon is a combo of 3 enzymes (lipase, protease and amylase), must be swallowed as otherwise cause damage to oral cavity
  = nutritional supplements - needed as amount of nutrients patients receives is sub-optimal

Question 16

why is exercise needed to treat CF

Answer 16

• necessary to keep lung function optimal

- necessary to build physical bulk and strength

Question 17

how does transplantation treat CF

Answer 17

• is not a cure
• if end stage lung disease
• heart lung transplant = survival 70% up to 2 years
• 5-10 years life
• means you won’t have CF in lungs anymore as cells from donor in the lungs not the recipient

Question 18

how does gene therapy work for CF

Answer 18

• replace defect gene with correct gene
• problem however as when this gene dies it will be replaced with the defected gene again
• is easy to get into an adult cell as use a virus

Question 19

what is the most common lung cancer

Answer 19

• squamous cell carcinoma
• 40%
• don’t usually have squamous cells in lungs, only happens due to irritation for smoking causing metaplasia

Question 20

what is the most common cause for lung cancer

Answer 20

smoking

Question 21

what are other types of lung caner not related to smoking

Answer 21

• small cell = 25%
• large cell = 20%
• adenocarcinoma = 15%

Question 22

what is a major problem in treating lung cancer

Answer 22

• there is often no symptoms until the tumour is advanced

Question 23

what are the main effects of a lung tumour

Answer 23

• cough
• haemoptysis = blood stained sputum as tumours are very vascular so bleed easily
• pneumonia = tumour has grown across airway so nothing (bacteria etc) can get out and pneumonia is an effect of this
• metastasis = bone, liver, brain

Question 24

what are some other effects of lung tumours

Answer 24

• dysphagia = tumour suppressing oesophagus so patient will get food stuck
• superior vena cava obstruction = put pressure in capillaries up and cause swelling and prominent veins in head and neck
• recurrent laryngeal nerve palsy = one side of larynx gets paralysed

Question 25

how long can it take for tumour to develop from smoking

Answer 25

- up to 20 years

Question 26

what do peripheral tumours tend to do in lungs

Answer 26

tend to stay in one lobe

Question 27

what is the treatment for lung cancer

Answer 27

- there are a small number of things that can be done - by the time the patient presents the tumour will have spread so you can't get control of it with surgery so rely on immunotherapy - earlier it is diagnosed the better - DONT SMOKE

Question 28

what is obstructive sleep apnoea

Answer 28

- airway obstruction whilst asleep - stop breathing while sleeping - 10 seconds or more duration - airway muscle tone drops

Question 29

what are some effects of sleep apnoea

Answer 29

- may be snorers - drowsiness during the day due to lack of sleep - increased risk of MI as blood O2 drops causing chronic hypoxia - higher chance of acute CV events

Question 30

what are the 2 types of sleep apnoea

Answer 30

- OSA = obstructive sleep apnoea - central = more common snorer - can get a combo of both

Question 31

what is the most common type of sleep apnoea

Answer 31

OSA

Question 32

how is sleep apnoea measured

Answer 32

- with AHI - apnoea/hypoapnoae index - score <10 then few problems

Question 33

how does the airway become blocked in sleep apnoea

Answer 33

- tongue flops against the soft palate and blocks the airway - can get no air into airway - patient wakes up when the body is so hypoxic that muscles respond - the more pressure the patient has down the way the worse it is = worse for obese patients

Question 34

what is CPAP for sleep apnoea

Answer 34

- continuous positive airway pressure - blows air into upper airway enough to keep airway open - have a mask over nose as most people with sleep apnoea sleep with their mouths closed - makes a noise

Question 35

how do mandibular advancement devices help sleep apnoea

Answer 35

- pulls mandible forward to pull tongue forward so it can't flop back - pulls mandible in front of maxilla - does work but is very uncomfortable for patients = they will likely want to try it but will not like it