breathing Flashcards
boyle’s law
states that the pressure exerted by a gas is inversely proportional to to its volume (P a 1/V).
Note that gases (singly or in mixtures) move from areas of high pressure to areas of low pressure.
Dalton’s law
states that the total pressure of a gas mixture is the sum of the pressures of the individual gases.
Charles law
states that the volume occupied by a gas is directly related to the absolute temperature (v a T)
henry’s law
states that the amount of gas dissolved in a liquid is determined by the pressure of the gas and it’s solubility in the liquid.
expiratory reserve volume
1100 mL
what is the vital capacity volume
4600 mL
inspiratory reserve volume
3000 mL
dead space volume
150 mL
what is the alveolar ventilation pressure for o2
13.3 kPa - 100mm hg
what is the alveolar ventilation pressure for Co2
5.3 kPa - 40 mm hg
during inspiration diaphragm does
contract and the volume increases
during expiration the diaphragm does
relax and the volume decreases
intra thoracic alveolar pressure is
negative or positive in comparison to atmospheric pressure
intra pleural pressure
always negative
trans pulmonary pressure
always positive
the pulmonary circulation is an example of what system?
high flow, low pressure system
tissue values partial pressure of oxygen and carbon dioxide
02 - 40 mmHg (5.3kPa)
C02- 46 mmHg (6.2kPa)
factors that affect gas exchange are
partial pressure gradient
gas solubility
surface area
thickness of membrane
what is the perfect ventilation: perfusion ratio
1
alveolar dead space causes
pulmonary vasodilation in response in increase oygen and bronchial constriction in response to alveolar decreases carbon dioxide levels
anatomical dead space refers to
air in the conducting zone of the respiratory tract
Type 2 alveolar cells produce what which does what?
surfactant increases lung compliance reduces recoil makes breathing easier effective in small alveoli relaxes water tension
equation of LaPlace
P=2T/r
high compliance refers to
large increase in lung volume in response to a small decrease in ip pressure
compliance represents
stretch ability
examples of obstructive lung disorders
asthma
COPD (bronchitis or emphysema (loss of elasticity) - very low FEV1, slightly low FVC (low ratio)
examples of restrictive lung disorders
fibrosis
infant respiratory distress syndrome (no surfactant)
oedema
Pneumothorax
normal or elevated FEV1/FVC ratio, but severely decreased lung capacity. use FEF.
what is the test for breathing?
spirometry
haemoglobin increases oxygen carrying in RBC to how much?
200ml
02 solubility in water is
0.03ml/L/mmHg
what is the oxygen demand of resting tissues?
250ml/min
Haemoglobin A consists of
2 alpha and two beta strands with each having a heme group with an iron centre
each gram of haemoglobin can bind to
1.34ml of oxygen
how long does oxygen saturation with haemoglobin take?
0.25 seconds
at resting cell partial pressure of 40mm Hg o2 what is the saturation of haemoglobin
75%
what factors effect haemoglobin saturation
2,3-DPG, pH, PCO2, and temperature
how many more times stronger is carbon monoxide’s affinity for haemoglobin
250x
a PCO of what is sufficient for causing carboxyl haemoglobin formation
0.4mmHg
how is carbon dioxide transported?
7% directly in plasma
23% as deoxyhaemoglobin
70% as bicarbonate ions
hypoventilation will result in respiratory..
acidosis
hyperventilation will result in respiratory..
alkalosis
the DRG controls
the dorsal respiratory group controls the inspiratory muscles
the VRG controls
the ventral respiratory group controls expiratory muscles and inspiratory pharynx, larynx and tongue muscles
the central chemoreceptor in the medulla is driven by
hypercapnea - raised partial pressure of carbon dioxide
during acidosis ventilation is
stimulated
during alkalosis ventilation is
inhibited and vomiting
FEV1/FVC <70%
obstructive lung disease
FEV1 > 80%
normal
FEV1 < 80%
restrictive lung disease
what are the possible complications of CODP
Pneumonia macro nutrient deficiency muscle wasting polycythaemia pulmonary hypertension Cor pulmonale depression pneumothorax
examples of short acting bronchodilators
SABA (salbutomal) or SAMA (ipratropium)
examples of long acting bronchodilators for worsening FEV1
LAMA ( long acting anti-muscarinic agents) or LABA (long acting beta 2 agonist)
high dose inhaled corticosteroids for even worse FEV1 examples
Relvar, fostair MDI, LABA
list the COPD management value pyramid from top to bottom
telehealth for chronic disease, triple therapy, LABA, tiotropium, pulmonary rehabilitation, stop smoking wit pharmacotherapy, flu vaccinations
oxygen treatment of 7.3 to 8 kPa should be given for COPD if
polycythaemia
nocturnal hypoxia
peripheral oedema
pulmonary hypertension
asthma definition
Episodic wheeze and/or cough in a clinical setting where asthma is likely and other rarer conditions have been excluded”
what percentage of kids in the uk are on inhaled steroids
5%
is a cough predominant or cough variant asthma possible?
must have a wheeze, cough predominant common no such thing as cough variant asthma
what are the mechanisms for a wheeze in asthma
bronchoconstriction
airwall thickening
luminal secretions
what is the treatment for responsiveness’ in asthma
ics for two months
ideally for asthma there should be
response to treatment
shortness of breath at rest
wheeze
parental asthma
Acute epiglottitis is caused by
group A beta haemolytic streptococci
what are the three main components of the respiratory tract defence mechanism
alveolar macrophages
mucociliary escalator
cough reflex
bronchopneumonia appears on a x ray as
bilateral patchy opacification due to the consolidation of pus in the alveoli
what percentage of bronchiectasis starts in childhood
75%
what are the clinical features of bronchiectasis
cough, abundant foul sputum, chronic infection, coarse crackles, haemoptysis
what are some of the potential causes of aspiration pneumonia
vomiting oesophageal lesion obstetric anaesthesia neuromuscular disorders sedation
what is type 1 respiratory failure characterized by
PaO2 <8kPa
how is type 2 respiratory failure characterized by
PaCO2 >6.5kPa
what are the four abnormal states associated with hypoxaemia
ventilation/perfusion imbalance
diffusion impairment
alveolar hypoventilation
shunt
embryonic phase of lung morphogenesis lasts for
3-8 weeks
the pseudo glandular phase of lung morphogenesis lasts for
5-17 weeks
canalicular phase of lung morphogenesis lasts for
16-26 weeks, at this point extra uterine life is possible at end of this stage
saccular phase of lung morphogenesis lasts for
24-38 weeks
alveolar phase of lung morphogenesis lasts for
36 weeks ~ 2-3 years
what are some common lung developmental diseases
airway stenosis airway malacia pulmonary agenesis trachea-oesophageal fistula bronchogenic cyst congenital pulmonary anomalies
when is a patient most likely to present features
fetus - ultrasound - 75%
newborn - 10%
childhood 15%
what are the characteristics of trachea bronchomalacia
seal like cough
early onset
breathlessness
stridor/wheeze
what treatment do you avoid with bronchomalacia
asthma treatments such as bronchodilators
how long does diaphragm development take
18 weeks
what are the fetal origins of COPD
utero nicotine exposure fetal infection malnutrition premature birth genetic
what are the paediatric origins of COPD
infection ETS (A1 AT deficiency) environmental lack off nutrients genetic
COPD is the
3rd leading cause of death in the world
normal FEV1 is about
4 litres
normal FVC is about
5 litres
COPD can also be measured by
PEFR: Peak expiratory flow rate
normal PERF rate
400-600L/min, 80-100% pass rate
chronic bronchitis is clinically defined as
productive cough for 3 consecutive months, or 2 or more consecutive years.
the definition of emphysema is
Increase beyond the normal in the size of airspaces distal to the terminal bronchiole arising either from dilatation or from destruction of their walls and without obvious fibrosis
centri-acinar
begins with bronchiolar definition measured by number related to inflammation not everywhere still alveolar damage closer to the bronchioles
pan-acinar
stems from alpha 1 antitrypsin deficiency found everywhere measured by area towards the ends of the bronchioles more alveolar damage
peri-acinar
airpsaces are larger than 1 cm in space, can cause the lung to collapse and pulmonary distress. singularly a bulla if >1cm. bleb describes a bulla just underneath the pleura
what part of COPD can be targeted pharmacologically
small airway inflammation and muscle tone
what is an important aspect of emphysema
loss of alveolar attachments
how many patients present with late stage lung cancer
2/3rd’s
order of systematic review of a chest x-ray
name lines/metal heart mediastinum lungs zones bones diaphragm soft tissue
how long before you should be concerned for a lobar lung collapse
2 to 3 weeks
a pulmonary mass is
an opacity over 3cm
a pulmonary nodule is
a mass up to 3cm
tests to determine T in a TNM
CT PET or bronchoscopy
tests to determine N in TNM
PET CT mediastinoscopy
EBUS/ECHO
tests to determine M in TNM
PET CT, bone scan
what is the analogue used in a PET CT scan
18F-FDG glucose
T1
<3cm
T 2
3-5cm or involves main bronchus, visceral pleura or obstruction
T5
5-7cm invading chest wall, phrenic nerve or parietal pericardium
T4
larger than 7cm and invading vertebral body, trachea, heart, laryngeal nerve, diaphragm etc, or tumours in separate lobe
N1
ipsilateral nodes or intrapulmonary nodes
N2
ipsilateral mediastinal and sub carinal
N3
contralateral mediastinal, hilar or supraclavicular.
what percentage of lung cancer is attributable to smoking
> 85%
in the lung periphery a tumour is likely to be
an adenocarcinoma, due to bronchi alveolar stem cell transformation
in central airways a tumour is likely to be
squamous cell carcinoma as bronchial epithelial stem cells transform - strongly associated with smoking
what oncogene is most smoking induced in adenocarcinogensis
KRAS then EGFR
what are the local effects of lung cancer
bronchial collapse, lipid pneumonia, infection/abcess or bronchiectasis
pleural inflammation
chest wall invasion
invasion of the phrenic, laryngeal nerve, brachial plexus, cervical sympathetic, and mediastinum.
lymph node metastasis
bronchiectasis refers to
permanent enlargement of the airways
distant effects of lung cancer
metastases of liver, adrenal, bone, brain and skin, neural and vascular problems
paraneoplastic syndromes
finger clubbing
hypertrophic pulmonary osteoarthropathy
increase in ACTH and siADH indicates what type of carcinoma
small cell
increase in PTH indicates
squamous cell
what is the 5yr prognosis for lung cancer
9.8%
4% for small cell carcinoma
what are the predictive biomarkers for adenocarcinoma
EGFR, KRAS, HER 2 BRAF
ALK translocations and ROS 1 translocations
in non-small cell carcinoma what is the immune checkpoint target and biomarker
PD1/PDL1, CTLA4
what is the 5 year prognosis for a T1 stage
70%
what is a 5 year prognosis for a N2 stage
16%
what is the medication for a pulmonary embolism
Low molecular weight heparin e.g. dalteparin Warfarin Direct Oral Anticoagulants (DOAC) rivaroxaban, apixaban Thrombolysis Alteplase (rt-PA)
pulmonary hypertension is defined as
pulmonary artery pressure above 25mm Hg
what is the specific treatments for pulmonary hypertension
Calcium channel antagonist e.g. amlodipine Prostacyclin Endothelin receptor antagonists bosentan ambrisentan Phosphodiesterase inhibitors sildenafil tadalafil
what are the infective agents that are viral for upper respiratory tract infections
Viral Adenovirus Influenza A, B Para’flu I, III RSV Rhinovirus
bacterial agents for upper respiratory infections
Bacterial H influenzae M catarrhalis (Mycoplasma) (S aureus) Streptococci B haemolytic, S pyogenes Non haemolytic, S pneumoniae
how long should a runny nose go for?
16 days
average duration of an earache
9 days
should you offer antibiotics to treat otitis media
not really, doesn’t offer immediate relief and by the time action is effective there is no point.
what should you give for tonsillitis
not amoxycillin
10 days penicillin.
how long should a sore throat last for
7 days
croup signs
stridor, barking cough, hoarse throat
croup treatment
oral dexamethasone
epiglottis signs
stridor, drooling
epiglottis treatment
intubation and antibiotics
croup duration
3 days
what are the antenatal causes of COPD predisposition
nicotine exposure infection maternal nutrition premature micronutrients
what are the post natal causes of COPD disposition
infection growth alpha tyrosin deficiency environmental pollution micro nutrients
human development pre-embryonic phase
0-3 weeks
embryonic phase of foetal development
4-8 weeks
foetal phase lasts for
9-40 weeks
after several replications the zygote forms
a morula
a fetus inherits mitochondrial diseases form
the mother
a morula develops into
a blastocyst, containing a blastocystic cavity, inner cell mass and trophoblast
how long does it take the blastocyst to reach the uterus?
5 days
abnormal uterine ciliary function could result in
an ectopic pregnancy
implantation occurs
day 7
the trophoblast forms what, and what is its function?
the chorion, and it implants, forming a part of the placenta and secretes chorionic gonadotropin
the chorion fuses with
the decidua basalis
the inner mass of cells in the blastocyst forms
a bilaminar disc the epiblast with the amniotic sac above, and the hypoblast with the yolk sac below.
the function of the placenta?
foetal nutrition, transport of waste and gases, immunity
what is the order of events for the trilaminar disc formation
primitive steak in the epiblast, axis formation, cell proliferation, displacement of hypoblast and formation of ectoderm, mesoderm, endoderm. cells now specialised.
the ectoderm forms
the notochord which lies between the mesoderm/endoderm, neural plate, which then forms the neural tube through invagination between the ectoderm/mesoderm
the mesoderm splits into
paraxial plate, intermediate plate, and the lateral plate
the lateral plate forms the
somatic and splanchnic mesoderm space in between the intraembryonic coelom
to form the body cavity and coverings
the intermediate plate forms the
urogenital system
the paraxial mesoderm forms
somites
the heart starts to beat on the
24th day
how any pairs of somites form
43
the endoderm folds to form
the gut
somites divide to form
dermatome, myotome and sclerotomes
what weeks is the greatest sensitivity to teratogens?
weeks 3-8
the tracheal budding begins at what week?
4rth week
the protruding foregut is coated in what?
splanchnic mesoderm
a fistula is
an abnormal passage between two organs
an atresia is
orifice being abnormally sealed
the parietal pleura develops from
the somatic mesoderm
what are some embryonic congenital conditions
accessory lobe
lobe of azygos vein
agenesis of lung
the septum transversum forms the
central tendon of the diaphragm
the pleuroperitoneal membranes form the
primitive diaphragm
the dorsal mesentery of the oesophagus forms the
median portion and crura of the diaphragm.
muscular ingrowth from the lateral walls from what aspect of the diaphragm
the peripheral parts.
the septum transversum migrating brings what nerves
C3,4,5,
three defects of diaphragmatic hernia
posterolateral, anterior and central
what are the two types of hiatus hernia
parasophageal hernia (rolling) and sliding hiatus hernia
what causes acute epiglottis?
group A beta haemolytic streptococci or haemophilus influenza type B
what are the aetiological types of pneumonia
Community Acquired Pneumonia Hospital Acquired (Nosocomial) Pneumonia Pneumonia in the Immunocompromised Atypical Pneumonia Aspiration Pneumonia Recurrent Pneumonia
what are the patterns of pneumonia
Bronchopneumonia
Segmental
Lobar
Hypostatic
Aspiration
Obstructive, Retention, Endogenous Lipid
what are the complications of pneumonia
Pleurisy, Pleural Effusion and Empyema Organisation mass lesion COP(cryptogenic organising pneumonia (BOOP)) Constrictive bronchiolitis Lung Abscess Bronchiectasis
why does pneumonia cause hypoxemia
Ventilation / Perfusion abnormality (mismatch)
Bronchitis / Bronchopneumonia
Shunt
Severe bronchopneumonia
Lobar pattern with large areas of consolidation
what are the symptoms of lung cancer
chronic coughing difficulty swallowing wheezing chest/bone pain chest infection haemoptysis weight loss SOB raspy voice
what are the clinical signs of lung cancer
- Chest signs
- Clubbing
- Lymphadenopathy
- Horner’s syndrome
- Pancoast tumour
- Superior vena cava obstruction
- Lymphadenopathy
- Hepatomegaly
- Skin nodules (metastases)
what is the dynamic turnover of pleural fluid in an hour
30-75%
what is the negative pressure of the pleura
-0.66kPa
a transudate is characterized by and caused by??
imbalance of hydrostatic forces, normally bilateral <30g/L proteins. range of conditions such as liver cirrhosis, peritoneal dialysis and left ventricular failure.
an exudate is characterized by and caused by?
increased permeability and unilateral. >30g/L proteins. caused by inflammation in response to malignancy, embolism or autoimmune disease.
how large a volume for the effusion before it is visible on a cxr
200ml
what needle is used for a pleural biopsy and how many samples?
Abram’s needle.
at least 4
a non-iatrogenic pneumothorax means
penetrating chest injury or blunt chest injury
a iatrogenic pneumothorax examples are
biopsy acupuncture, cannulation.
what’s a large pneumothorax defined as
rim of air >2cm
what’s the management for a pneumothorax?
cannula inserted in the 2nd intercostal space along the mid clavicular line then insert intercostal chest drain.
what is asbestos?
highly fibrous naturally occurring mineral
what is the most dangerous form of asbestos
crocidolite
how does CF effect fertility in men
blocked/absent vas deferens
when is a patient considered for lung transplant
once FEV1 <30%/predicted to be soon
what is the genetic prevalence of CF
1:25
that is the function of the CFTR
active transport of chloride regulating liquid volume, its compromise results in cilia dysfunction
what is the accepted sweat chloride values
> 60 is CF
<30 normal if over the age of 6 months
what is the treatment for pancreatic insufficiency
fat soluble vitamins, Proton pump inhibitors, high energy diet and enteric enzyme pellets
common pathogens for CF
Staphylococcus aureus and Haemophilus influenzae in early years
Pseudomonas aeruginosa later
uncommonly there is atypical mycobacteria e.g. m abscessus
restrictive lung disease is associated with
reduced compliance
low FEV 1 and low FCV but normal ratio
reduced gas transfer
V/Q imbalance.
restrictive lung disease often results in
type 1 respiratory failure.
diffuse alveolar damage results from
type 2 cell necrosis, has an exudative phase, hyaline membrane formation phase. can be fatal or progress to fibrosis.
sarcoidosis is
multisystem granulomatous disorder
sarcoidosis presents with
arthralgia, erythema nodosum and bilateral hilar lymphadenopathy, shortness of breath and cough with abnormal x ray.
hypersensitivity pneumonia is an example of
type 3 and type 4 hypersensitivity reactions.
usual interstitial pneumonia demonstrates
temporal and spatial heterogeneity - patches of recent and old trauma.
how many people are infected with tuberculosis world wide?
2 billion
what bacteria is responsible for tuberculosis?
mycobacterium
mycobacteria are
non-motile bacillus slow growing aerobic thick cell wall resistant to acid, alkalis, detergents, neutrophils and macrophages
name of the stain for mycobacterium
zhiel neilson stain
what is the immunopathology of tuberculosis
activated macrophages then epithelioid cells then langhans cells. accumulation, the granuloma formation. it then forms a central caseating necrosis which may calcify.
primary infection of tuberculosis may present with
erythema nodosum
cough, fever, but often asymptomatic
post primary infection often involves the
skeletal system, the meninges, pleural effusion and most the tissues.
what is the Tb regime
4 drugs for two months Rifampicin Isoniazid Ethambutol Pyrazinamide
then two drugs for 4 months
rifampicin
isoniazid
side effects of the Tb multi drug therapy?
Rifampicin Orange ‘Irn Bru’ urine, tears
Induces liver enzymes, prednisolone, anticonvulsants
Oral contraceptive pill ineffective
Hepatitis
Isoniazid Hepatitis Peripheral neuropathy (pyridoxine B6)
Ethambutol Optic neuropathy (check visual acuity)
Pyrazinamide Gout
screening test for an under 16 year old for tb
no immunity to tuberculinprotein so the mantoux or heaf test
older then 16 screening test for tb
chest x-ray
what does a right heart catheter measure?
wedge pressure, cardiac output and the blood pressure of the artery.
what hormone secretion is associated with small cell cancer lung
ACTH siADH
what hormone secretion is associated with large cell carcinoma lung
PTH
asthma is the result of IgE antibodies inappropriately reacting to inert antigens, causing mast cells to release.
microthrombins , prostaglandins, histamine and lysosomal enzymes in a exaggerated inflammatory response. Spasmogens such as histamine also trigger an immediate response
you perform aspiration and perform a look and sniff, what do this signs indicate foul smelling pus food particles milky blood stained blood
foul smelling - anaerobic empyema pus - empyema food particles – oesophageal rupture milky – chylothorax (usually lymphoma) blood stained - ?malignancy blood – haemothorax, trauma
name some chemotactic released in asthma
NCF
LTB4
PAF
ECF-A
name some spasmogens released in asthma
histamine
SRS
PG
PAF
CURB 1 pneumonia treatment
amoxicillin or clarithromycin
CURB 2 pneumonia treatment
amoxicillin and clarithromycin
CURB 3-5 pneumonia treatment
co-amoxiclav and clarithromycin
how quickly does small cell lung carcinoma double
every 29 days
what is the response rate of small cell lung cancer to therapy
90%
how many cycles of chemotherapy for lung cancer are undertaken
4 cycles
what Is the dosage of radiation for stage 3 lung cancer
55Gy+
what drugs are used for stage 1-2 adjuvant therapy for lung cancer
cisplatin and vinorelbine
how long does non small cell lung cancer take to double
129 days
what are the drugs of choice for small cell lung carcinoma
cisplatin and etoposide with early thoracic radiotherapy and prophylactic cranial radiation
how prevalent is asthma in the population
10%
what drugs to avoid with asthma managing
beta blockers
NSAIDS
asparin
sedative/opiates
what drugs to give during an acute asthma attack
beta 2 agonists, steroids, leukotriene receptor antagonist, monoclonal antibodies
theophyllines
magnesium
oxygen
adverse effects of beta 2 stimulants
tremor, cramp, headache, flushing, palpitations, angina
side effects of long term inhaled steroidal use
oropharyngeal candidiasis
dysphonia
acute asthma signs
PEF 33%-50%
respiratory rate of more than 25/min
heart rate above 110 min
inability to complete a sentence in a breath
life threatening asthma signs
altered consciousness exhaustion hypotension cyanosis silent chest poor respiratory rate raised PCO2
what is the duration of a cough associated with bronchiolitis
25 days
duration of bronchiolitis
16 days
would you treat tracheitis with antibiotics?
yes, Augmentin
bronchitis antibiotics?
no
LRTI/pneumonia antibiotics?
oral amoxicillin
bronchiolitis, antibiotics?
no
empyema, antibiotics?
yes, IV