lecture 6? airway injury following lung transplantation

Question 1

how does survival change after lung transplant?

Answer 1

• less early mortality
• long term survival is around 7 years after transplant

Question 2

why does survival after lung transplant decline faster?

Answer 2

• constantly exposed to environment
• vulnerable to pathogens inhaled etc.

Question 3

what is chronic lung allograft dysfunction (CLAD)?

Answer 3

• narrowing of bronchiolar lumen by fibrous tissue
• chronic rejection

Question 4

how many recipients develop CLAD within 3 years?

Answer 4

• 50%
• no improvements over last decade despite improving medicines

Question 5

how does FEV1 change after transplant?

Answer 5

• shows overall deterioration
• fixed airflow limitation

Question 6

what does this decreasing FEV1 after transplant lead to?

Answer 6

• bronchiolitis obliterans syndrome

Question 7

what is brochiolitis obliterans syndrome?

Answer 7

• chronic lung allograft dysfunction
• affects majority of lung transplant recipients

Question 8

what are the characteristics of BOS?

Answer 8

• dyspnea (shortness of breath)
• persistent progressive cough
• wheezing
• fatigue

Question 9

what pathology underlies BOS?

Answer 9

• obliterative bronchiolitis (inflammatory cell fibrosis)
• blockage of airways so no air flow to lungs

Question 10

how does the response to injury lead to BOS?

Answer 10

• rejection due to aspiration/ infection
• neutrophil production to protect
• epithelial damage occurs
• causes airway remodelling
• fixed airway obstruction

Question 11

what is airway remodelling?

Answer 11

• change in structure and airflow of the lungs

Question 12

what methods are used to diagnose and test for BOS?

Answer 12

• flexible fibrotic bronchoscopy
• bronchioalveolar lavage

Question 13

what is a biopsy?

Answer 13

• small amount of tissue taken for analysis and diagnosis

Question 14

what is a bronchialveolar lavage?

Answer 14

• minimally invasive procedure
• tests for lung disease
• bronchoscope passed through mouth or nose
• measured amount of fluid collected for examination

Question 15

what does aspiration of reflux cause?

Answer 15

• pneumonia

Question 16

what can occur during lung transplantation?

Answer 16

• chest openend
• possibility of vagal nerve damage
• gastroparesis slowing down gastric emptying
• blunted cough and clary clearance mechanisms

Question 17

what is the function of vagus nerve?

Answer 17

• emptying of GI system

Question 18

what are the methods of treatment for the allograft damage?

Answer 18

• proton pump inhibitors
• surgical fundoplication

Question 19

what is pH-impedence?

Answer 19

• catheter going down the oesophagus
• liquid goes up from stomach as it would in reflux event
• change in electrical resistance across bands on catheter
• data recorded to measure travel and reflux events in 24hours

Question 20

what is pepsin?

Answer 20

• gastric acid protease
• proteolytic activity
• can be used as a marker of aspiration

Question 21

what does pepsin show?

Answer 21

• high pepsin present in all lung diseases
• acute lung disease has highest levels of pepsin

Question 22

what is the correlation between GORD and lung injury?

Answer 22

• the more reflux that occurs, the more neutrophils present
• highlights infection

Question 23

how does the microbiome link to gastric juice?

Answer 23

• bacteria including pseudomonas was found in gastric juice of patients with more alkaline pH of 5-8