Resp Flashcards

1
Q

What is pleura made from?

A

a serous membrane of a single layered mesothelial cells & thin CT underneath

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is parietal pleura?

A

the inside part lining each hemithorax and continues with the visceral pleura at hilum of lung

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is visceral pleura?

A

lines the outside of lunges extending between lobes into the fissures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the BS of pleura?

A

Intercostal & internal thoracic arteries and veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Innervation of pleura?

A

Parental pleura = somatic (intercostal & phrenic nerves) & autonomic
Visceral = no somatic, only autonomic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the pleural cavity/space?

A

potential peace between layers of pleura which is filled with fluid produced from the parietal space & absorbed by parietal lymphatic vessels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the function of pleural fluid?

A

allow the 2 layers to slide - allowing chest & lung moment in breathing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is an important characteristic of the pleural fluid?

A

Surface tension - provides cohesion keeping lung surface in contact with thoracic wall so when thorax expands in inspiration, the lunch expands and fills with air along with it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is the apex of the lungs?

A

Above 1st rib, into the neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where is the base of lungs?

A

concave shape resting on diaphragm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many lung lobes are there?

A
Left = 2 --> 1 fissure
Right = 3 --> 2 fissure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the 3 surfaces of the lung?

A

costal, mediastinal, diaphragmatic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the names of the Right lobes and lung fissures?

A

Superior, middle & inferior lobes created b the right oblique & horizontal fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Left lung lobes and fissure?

A

superior and inferior lobes created by left oblique fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is in the lung hilum?

A

bronchi, pulmonary arteries, superior & inf. pulmonary veins, pulmonary plexus of nerves and lymphatics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the pathway of the trachea?

A

Lower border of cricoid cartilage terminating into the Right and Left main bronchi at sternal angle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What shape cartilage are found in trachea?

A

c-shaped

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What epithelium is the trachea?

A

pseudostratified ciliated columnar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the carina?

A

the angle between the the right & left main bronchi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is the pathway of the airways?

A

Trachea> R main bronchus> lobar bronchi> segmental? bronchioles> terminal bronchioles>alveolar ducts> alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What bronchus is shorter wider and more vertical?

A

the right main bronchus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the blood supply of the lungs from the heart?

A

1 Pulmonary A from pulmonary trunk

2 Pulmonary veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the BS to the supporting lung structures?

A

Bronchial arteries coming from the Thoracic aorta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the mediastinum?

A

central compartment of the thoracic cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the mediastinum covered by?

A

the mediastinal pleura

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is contained in the mediastinum?

A

all thoracic viscera except lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Where is the heart and great vessels located?

A

the middle inferior mediastinum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is important about the pulmonary circ. compared to systemic?

A

pulm. circ. must accept entire CO and work with low resistance as many capillaries in parallel and articles with little smooth muscles - so the circulation operates under a low pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the Boyle’s law?

A

Given amount of air is compressed into smaller volume, molecules hit more often so increase pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Kinetic theory of gases?

A

gases move around a space and collide with walls to generate pressure. the more freq. and harder collisions, the more pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Charle’s law?

A

kinetic energy increases with temp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Universal gas laws?

A

calculation of volume when pressure and temp change

PxV = gas constant x Temp (kelvin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the partial pressure?

A

in a gas mixture, it’s the proportion of pressure a particular gas gives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

vapour pressure?

A

partial pressure of gas dissolved into evaporated water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

saturated vapour pressure?

A

rate of molecules entering and leaving water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

tension?

A

how readily gas leaves a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Content of gas in liquid?

A

Solubility x tension

dissolving x readily leaving

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Total gas content?

A

TC = reacted gas + dissolved gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Total content of O2 in blood?

A

O2 bound to Hb + O2 dissolved in plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Tidal volume?

A

the volume of air breathed in and out in normal inspiration & expiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Respiratory rate?

A

breaths per minute

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What are the pulmonary circulations?

A

Pulmonary - to the alveoli for gas exchange, and bronchial - part of systemic to meet lungs demand

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Key features of the pulmonary circulation?

A

Accepts all of CO
Low resistance as short, wide capillaries with many in parallel and the arterioles have little smooth muscles
Low pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is ventilation: perfusion matching?

A

Efficient oxygenation requires the ventilation to the alveoli to be matched by the blood perfusion via pulm. circ.
The V/P ratio = 0.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How to maintain the V/P ratio?

A

Hypoxic pulmonary vasoconstriction - to increases resistance so less flow which is instead diverted to well ventilated areas.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is a complication of chronic hypoxic vasoconstriction?

A

Right ventricular failure as chronic increase in vascular resistance = after load on right ventricle causing failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What is the upper resp. tract?

A

Above the thorax - nasal cavity, pharynx, larynx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the lower resp. tract?

A

Inside the thorax:
Trachea, Main bronchi, Lobar bronchi, segmental bronchi, bronchioles, terminal bronchioles, resp. bronchioles, alveolar ducts and alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

How many lobar bronchi are there?

A

3 on right
2 on left
Have cartilage in walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Characteristic of bronchioles

A

No cartilage in walls and more smooth muscle than bronchi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Function of cartilaginous rings in trachea and bronchi?

A

To hold the airways open when moving neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Characteristics of alveoli?

A

single cell thick
Short diffusion distance with Type 1 Simple Squamous cells
Type 2 cells release surfactant to reduce surface tension of alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

How do bronchioles draw air in?

A

Increasing volume by using smooth muscle in walls

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What lines the conducting portion of the tract?

A

Mucous membranes containing goblet cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What lines the pleural sacs enveloping the lungs?

A

Serous membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is the epithelium for the upper tract, trachea and bronchi?

A

Pseudostratified, ciliated with goblet cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is the epithelium for the bronchioles and terminal bronchioles?

A

simple columnar with cilia and clara cells, no goblet cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is the epithelium for respiratory bronchioles and alveolar ducts?

A

simple cuboidal, clara cells and cilia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What is the epithelium of the alveoli?

A

Simple squamous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What are clara cells?

A

Cells that release surfactant to prevent the walls sticking together during expiration from surface tension.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Patient’s blood results indicates abnormal levels of protein CC16, what does this means?

A
High = leakage across air-blood barrier
Low = lung damage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is it important that there are no goblet cells in the terminal bronchiole?

A

Prevent person drowning in own mucus as very narrow airways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Describe terminal bronchioles?

A

no alveolar openings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Respiratory bronchioles?

A

some wall openings onto alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Describe the alveolar duct?

A

duct wall with openings everywhere for alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What is an alveolus?

A

a single alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What is the alveolar sac?

A

air space onto which many alveoli open onto

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Describe the structure of alveoli:

A

abundant capillaries
electric and reticular fibre network
covered in Type 1 pneumocytes - simple squamous
scattered Type 2 pneumocytes - simple cuboidal surfactant-releasing
macrophages lune the alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Describe how lungs inhale air?

A

Lungs: bronchioles dilate to increase radius - lowering resistance, decreasing pressure within the lungs drawing air in.

Muscles: external intercostals elevate the ribs in bucket-handle movement (30%), and the diaphragm contracts to descend to increase the chest volume

Chest wall: expansion, and due to surface tension by pleural fluid, the lung parietal pleura follows taking the visceral pleura with it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What muscles are involved with quiet breathing?

A

I: Diaphragm and external intercostal
E: none (elastic recoil)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What muscles are involved in forced breathing?

A

I: diaphragm, Ext. I, scalee, pec minor, SCM, serrates ant

E: Internal & Innermost I, abo. muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What determines the rate of gas exchange?

A

Surface area - lots of alveoli
Resistance to diffusion
- short dd
- CO2 is more soluble, so diffuses faster so diffusion only changes O2 as it is limiting
Gradient of partial pressures
- air pushed in and out of alveoli by pressure differences through inspiration & expiration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What is Inspiratory reserve volume?

A

Extra volume that can be breathed in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

What is Expiratory reserve volume?

A

extra air that can be breathed out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What is residual volume?

A

the volume left after max. expiration - only measured using helium diffusion, not a spirometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What is vital capacity?

A

the max inspiration and max expiration

~5L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What is functional residual capacity?

A

volume of air in lungs are resting expiratory level ~2L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What is inspiratory capacity?

A

the biggest breath from resting expiratory level ~3L

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

Draw a spirometer trace

A

See picture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What is Serial/ Anatomical Dead Space?

A

same air entering and leaving airway. Last air in = last air out so not used in gas exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is Nitrogen Washout test used for?

A

Measuring serial dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Describe the Nitrogen washout test

A
  1. Inhale 100% O2 - oxygen will mix with alveoli and will contain N2, but conducting airways will be just O2
  2. Exhale and measure % N2 in air expired
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What is physiological dead space?

A

volume of air not taking part in gas exchange = anatomical dead space + alveolar dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

How to measure alveolar ventilation rate?

A

about of air reaching the alveoli = Pulmonary vent rate - Dead space vent rate = RR(Tidal volume - dead space volume)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What is a pneumothorax?

A

integrity of the pleural seal is broken leading to the lung collapsing as air has entered between the 2 pleura layers so loss of fluid surface tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What is lung compliance?

A

the stretchiness of the lungs (volume change per unit of pressure)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

High lung compliance means…?

A

the lungs are easy to stretch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

What type of compliance do stiff lungs have?

A

low compliance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What type of compliance do elastic lungs have?

A

high compliance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What factors affect compliance?

A

elasticity of the lungs

surface tension - resist stretching

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

What is the surface tension when lungs are deflated?

A

lower

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

What is the surface tension when fully inflated lungs?

A

high surface tension

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

What type of breathing is easier?

A

little breaths as it takes less force to expand small alveoli than larger alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Explain laplace’s law:

A

Pressure related to radius of bubbles, so larger alveoli would eat smaller alveoli, but bigger alveoli have greater surface tension so surfactant is less effective. This pressure stops big alveoli eating small alveoli, so creates interconnecting set of bubbles with equal size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

Explain Poiseulle’s law:

A

resistance of tube increases with decreasing radius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

Describe the level of resistance of small airways:

A

Whilst having a small radius, because they are parallel they have a low resistance so easy flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

What ‘work’ is done to inspire?

A

Work against the elastic recoil of the lungs and thorax to overcome the elasticity of lungs and surface tension forces of alveoli

Overcome the resistance to flow in the airways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What is Forced Vital Capacity?

A

maximum volume expired from full lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

What is FEV1?

A

Forced expiratory volume in 1st second, speed of air flow - low if narrowed airways (COPD)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What is Restrictive disease?

A

Lungs are unusually stiff or inspiratory efforts are compromised by muscle weakness, injury or deformity.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

What is the FVC and FEV1 in restrictive disease?

A

FVC reduced
FEV1 > 70% of FVC
(difficult to fill lungs, but air comes out normally)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What is Obstructive defect?

A

small airways are compressed so high flow resistance during expiration leading to no more air being driven out of alveoli. Expiratory flow compromised

103
Q

What is the FVC and FEV1 in Obstructive defect?

A

FVC = normal
FEV1 = reduced
Lungs are easy to fill but hard to empty

104
Q

What is measure in vitalograph?

A

Volume expired against time

105
Q

What is measured in flow volume curves?

A

Volume expired against time, and Flow against Volume expired, taken from a vitalograph

106
Q

What is PEFR?

A

Peak Expiratory Flow Rate - seen on flow volume curves, the exp. flow is max when lungs are full, airway are stretched and resistance is minimum

107
Q

What happens to flow after PEFR?

A

Lungs compress are air leaving narrows the airways leading to increased resistance and decreased flow

108
Q

What does COPD look like on flow volume loops?

A

Same PEFR, but rapidly dropping flow after & same total volume expired.
More severe COPD leads to reduced PEFR

109
Q

What does Restrictive defect look like?

A

Normal PEFR, but smaller total volume expired (as less inspired)

110
Q

What does fixed airway obstruction look like?

A

No peak, but level PEFR limited in height

111
Q

What is helium dilution test used for?

A

Measuring Functional residual capacity which is used to calculate residual volume.

Helium = inert and can not diffuse across, known conc at start and new conc at end of normal exp. to calculate volume of lungs.

112
Q

What is Carbon Monoxide transfer factor used for?

A

the rate of CO transfer from alveoli to blood measures how well gas diffusion is.

Tiny fraction of CO as is toxic

113
Q

Solubility of water?

A

Not very soluble in water

114
Q

Draw an oxygen-Hb dissociation curve:

A

ppO2 of lungs = 13.3kPa

ppO2 of tissues = 5kPa

115
Q

Properties of Hb?

A

Reversible binding to O2
Tetrameric with 4 team groups so 4 O2 bind
Low affinity T-state when in tissues, high affinity R-state in lungs
sigmoidal binding curve = co-operative binding

116
Q

O2 dissociation and temperature?

A

decreased affinity

117
Q

O2 dissociation and low pH

A

decreased affinity

118
Q

O2 dissociation and high CO2

A

decreased affinity –> Bohr Effect shift curve to the RIGHT

119
Q

How does CO2 react in the blood?

A

Dissolved in water
reacting with water –> H+ & HCO3-

Binding to proteins –> carbamino compounds

CO2 mostly travels in the blood as HCO3-

120
Q

What is Henderson-Hasselbach equation?

A

pH= 6.1 + Log ({HCO3-] / (pCo2 x 0.23))

121
Q

What is the buffering effect of Hb?

A

Co2 reacts with water to produce H+ by carbonic anhydrase, which binds to Hb and pushes for more HCO3- production

122
Q

What is hypoxia?

A

Low alveolar O2 leading to low arterial O2

123
Q

Hypercapnia?

A

rise in alveolar, therefore arterial CO2

124
Q

Hyperventilation?

A

Vent. increase without change in metabolism

125
Q

What effect on pH does hyperventilation have?

A

Less CO2

Higher pH

126
Q

What effect on pH does hypoventilation have?

A

More CO2

Lower pH

127
Q

What are the effects of hypoventilation?

A

Respiratory acidosis and hypercapnia. Enzymes denature

128
Q

What are the effects of hyperventilation?

A

Respiratory alkalosis and hypocapnia, free calcium conc falls as Ca only soluble in acid–> fatal tetany as nerves = hyper-excitable

129
Q

What detects low pO2?

A

Peripheral chemoreceptors in carotid & aortic bodies. Fall in O2 supply to cells and only respond to large O2 drop.

130
Q

How do the peripheral chemoreceptors respond to a fall in O2?

A

Increasing the tidal volume to increase rate of respiration - hyperventilate
Directing blood to kidneys & brain
Increasing HR and CO

131
Q

How do peripheral chemoreceptors detect pCO2?

A

they don’t! dun dun duuuuuun!

132
Q

What detects blood pCO2?

A

Central chemoreceptors in the medulla of the brain

Small rise in pCO2 > hyperventilation

133
Q

How do central chemoreceptors work?

A

Art pCO2 = CSF pCO2 as CO2 transfers across the blood-brain barrier but HCO3- and H+ don’t.
CSF [HCO3-] are fixed by Choroid Plexus Cells, so pH rises with increased CO2 –> detected by Chemoreceptors so hyperventilate.

Persistently high CO2 –> CPC release more HCO3- to compensate therefore pH rises to normal but pCO2 remains high.

134
Q

Respiratory failure is when..?

A

Art pO2 falls below 8kPa

135
Q

What O2 saturation do clinicians aim for in T1RF?

A

94-98%

136
Q

What are the signs of T1RF?

A

Central and peripheral cyanosis, SOB, confusion, cor pulmonale, excess RBCs

137
Q

What are the signs of T2RF?

A

confusion, bounding pulse, headaches, flushing, CO2 retention flap

138
Q

Why does T1 become T2 RF?

A

The muscles and cells fatigue so produce CO2 which is not adequately removed from the blood

139
Q

What O2 saturation do clinicians aim for in T2RF?

A

88-92%

140
Q

Treatments for T2RF?

A

Controlled O2, Non-invasive ventilation - mask

141
Q

Causes of V/Q mismatch?

A

Ventilation problems = asthma

Perfusion problems = PE, pulmonary hypertension, R–>L shunt like patent foramen ovale

142
Q

Causes of diffusion failure?

A

Liquid: pulmonary oedema and pneumonia

Structural: Emphysema (LESS SA) and fibrosis (THICKER)

Affects O2 not CO2

143
Q

Causes of alveolar hypoventilation?

A

Obstructive: COPD, asthma

Restrictive: Obesity, fluid, fibrosis, chest wall problems, kyphosis, pneumothorax, Neuromuscular problems - resp. depression in opiate OD, head injury, muscle weakness

144
Q

Causes for reduced O2 carriage by Hb?

A

Anaemia

145
Q

What does a pulse oximeter measure?

A

the % saturation of O2 in Hb

146
Q

What does ABG measure?

A

amount of dissolved O2 in blood

147
Q

Consequence of chronic hypoxia?

A

Increased Erythropoietin production & increased vent.

148
Q

Chronic hypercapnia?

A

The Choroid Plexus cells release HCO3- to compensate for high CO2, hence hypoxia drives ventilation

149
Q

Key features about asthma?

A

Chronic, reversible airflow obstruction, characterised by inflammation and re-modelling of airway walls.

Triggers: cold, exercise, pollen, dust

It is treated with bronchodilators - salbutamol

150
Q

What is the pathophysiology of Asthma?

A

Acute - T1H, IgE mediated, mast cell release of histamine and prostaglandins

Chronic - T4H, TH2 cells release cytokines and leukotrienes to stimulate mast cells and eosinophils.

Asthma gives thicker smooth muscle and basement membranes (deposit collagen) > reduce radius > increase resistance > reduce flow

Goblet cell hypertrophy > dry cough

151
Q

Causes of asthma?

A

Genetic risk

Atopy: smoke, pollens, pollution, dust mites, fungus (aspergillus)

Stress: cold, exercise, viral URTI

Toxins: beta blockers, NSAIDs

152
Q

Clinical presentation of Asthma?

A

Wheeze - expiratory sound that varies intensity & tone (polyphonic)

Dry cough - worse at night, excrete induced

SOB - esp. with exercise

Chest tightness

Airflow obstruction (entry)

Hyper-resonant percussion of chest as lungs = hyper inflated

Patient using accessory muscle to breathe

Hyper inflated chest / barrel chest

Increased RR

153
Q

What investigations do you do fro asthma?

A
Bedside:
Sputum MC&S
Peak flow
Bloods:
eosinophilia, CRP
Imaging: CXR - hyperinflation
Atrophy: skin prick test

Spirometry - obstructive pattern:
FEV1 improves by 20% using salbutamol - bronchodilator reversibility

154
Q

Causes of asthmatic attacks?

A

X Tx adherence
Viral URTI
Allergens & triggering drugs (NSAIDs)

155
Q

Treatment for Asthma?

A

Education, prevention. drugs - B2-adrenoagonist - Salbutamol, anti-inflammatory - corticosteroids

156
Q

Obstructive airway conditions?

A

COPD, Asthma, lung cancer, bronchiectasis

157
Q

Constrictive airway conditions?

A

Pulmonary fibrosis

Kyphosis, scoliosis, NMD - brain, MS; obesity, pneumothorax

158
Q

What is COPD?

A

Chronic and slow-progressing airway obstruction, not fully reversible. Mostly caused by smoking.

159
Q

Pathophysiology of COPD?

A

Chronic Bronchitis: - chronic inflammation of bronchioles leading to fibrosis of airways and mucous gland hyperplasia

Emphysema: - destruction of alveolar walls leading to reduced SA for gas exchange and reduced expiratory volume. Often caused by smoking

160
Q

Clinical features of COPD?

A

Wheeze, SOB, cough with white sputum, weight loss

161
Q

Signs of COPD?

A

High RR, hyper-resonant and hyper inflated chest, cor pulmonate (raised JVP and Pulmonary oedema), barrel chest, obstructive breathing

162
Q

Causes of COPD?

A

Smoking
A1AT deficiency - young and genetic
Industrial pollutants

163
Q

Test for COPD?

A

Bedside: MC&S of white sputum

Bloods: FBC - raised RBCs, a1AT deficiency, ABG

Spirometry: Obstructive defect and FEV1 used to gage severity

CXR: hyperinflation, flattened diaphragm, bulla (air pocket), pulmonary vessel enlargement

164
Q

Treatment for COPD?

A

Conservative: stop smoking, pulmonary rehab - exercise training to increase capacity to

Meds: bronchodilators - salbutamol
steroids as prevention
mucolytics - reduce mucus production
Abi for infections

O2 therapy - but non-smoking and not pO2 dependant for ventilation

Surgical- lung volume reduction

165
Q

How do you assess the impairment from COPD?

A

MRC Dysponea scale: 1-5
1 being no trouble except breathlessness from strenuous exercise to 5- total breathlessness when dressing/unable to leave house

166
Q

What are the natural defences of the resp. tract against infection?

A

Mucus - traps bacteria
Cilia wafts them to the back of the throat to be swallowed
Sneezing & coughing reflex
Lymphoid tissue of pharynx, alveolar macrophages and secretory IgA and IgG

167
Q

What do URTI affect?

A

Nose, pharynx, epiglottis, larynx, sinuses and middle ear

168
Q

Viral causes of URTI?

A

Rhinovirus

influenza

169
Q

Bacterial causes of URTI?

A

Streptococcus pneumonia,
Haemophillis Influenza
Morexella

170
Q

Common URTI?

A

Rhino sinusitis and otitis media –> mastoiditis, meningitis and brain abscesses

171
Q

What is pneumonia?

A

a LRTI, inflaming the alveolar surfaces responsible for gas exchange and producing exudate

172
Q

Lobar pneumonia is..?

A

Pneumonia affecting a particular lobe caused by strep. pneumonia

173
Q

Bronchopneumonia is?

A

Diffuse and patchy - starting in airways and spreads to alveoli

174
Q

Aspiration pneumonia?

A

Aspiration of food, drink or vomit leads to pneumonia

175
Q

Interstitial pneumonia?

A

Inflammation of intersticium of lungs - epithelium, capillary end, BM

176
Q

Chronic pneumonia?

A

Persisting inflammation of the LRT over a long period of time

177
Q

How does pneumonia appear on a CXR?

A

consolidation - pus, cellular fluid

178
Q

Most common cause of community acquired pneumonia?

A

Strep. pneumoniae
Haemophilus influenza
Atypical: chlamydia pneumophilia

179
Q

Most common causes of hospital acquired pneumonia?

A

Pseudomonas aeruingosa, staphylococcus aureus, e.coli

Aspiration - stroke/elderly

Immunocompromised: TB, HSV, CMV, PCP

180
Q

Symptoms of pneumonia?

A

Productive cough - purulent, heamoptysis
Pleuritic chest pain
SOB
Fevers, rigors

181
Q

Signs of pneumonia?

A
Increased RR and HR
Fever
Cyanosis
Confusion
Consolidation - reduced expansion, reduced air entry, dull precision, bronchial breathing, crackles, reduced vocal resonance
182
Q

What is CURB-65?

A

C = confusion
U- urea >7mmol/L
R- RR>30
B = blood pressure 65

CURB 1 = mild, 2=moderate & hospital, 3+ = severe

183
Q

Investigations for Pneumonia?

A
Bedside:
MC&S of sputum
Urine for Ig - legionella
Blood:
FBC, U&Es CRP, LFTs, ABG & cultures - PCR viruses, serology

Imagining - CXR for consolidation & abscesses

184
Q

Tx for pneumonia?

A

Depends on CURb-65

Community: Amoxicillin & Doxycycline

Hospital: Co-amoxiclav

IV fluids, anti-paretics, analgesia, O2

185
Q

Outcomes of pneumonia?

A

Resolution

Pleural effusion & empyema
Abscesses
Septic shock

186
Q

Prevention of pneumonia?

A

Immunisation for flu

Prophylaxis - oral penicillin for asplenia, IC

187
Q

What atypical bacteria is responsible for TB?

A

Mycobacterium tuberculosis

188
Q

How is TB spread?

A

aerosol spread through droplets and coughs

189
Q

What does TB form on the pleural space?

A

Ghon focus

190
Q

TB involvement with the lymph nodes is called a..?

A

Ghon complex

191
Q

Primary TB symptoms?

A

Asymptomatic

192
Q

Primary Progressive TB?

A

TB spread extrapulmonry and military spread (throughout body) via lymphohaematogenous system

193
Q

Outcomes of TB?

A

Spontaneous resolution or localised infection - e.g. meningitis

194
Q

Military Tb?

A

widespread dissemination throughout body by bloodstream - primary or in reactivation. can causes retina involvement or ascites

195
Q

Dormant TB?

A

Infected, but TB is not expressing clinical or CXR signs. Will reactivate when weakened immune resistance

196
Q

Pathology of TB?

A

MB injected by macrophages which escape the phagolysosomes and multiply in the cytoplasm. The intense immune response causes destruction of local tissue –> cavitation of lungs & granuloma formation, and systemic cytokine-mediated effects - weight loss & fever

197
Q

Clinical presentation of primary TB?

A

Initially few symptoms - enlarged LNs

Post-primary:
Chronic cough, heamoptysis, fever, night sweats, weight loss and recurrent bacteria pneumonia

198
Q

Tuberculosis meningitis presentation?

A

Fever, headaches and deteriorating level of consciousness

199
Q

Common sites of TB infection?

A

Meninges,
kidneys,
lumbosacral spine - vertebral collapse and nerve compression
Large joints - destructive arthritis

200
Q

Signs of TB?

A

Pleural effusion - deviated trachea, stony dull percussion, reduced vocal resonance
CXR: shadowing, cavities, consolidation, cardiomegaly, military seeds

201
Q

Tuberculosis spondylitis?

A

Osteoarticular TB - affecting vertebral bones

202
Q

TB risk factors?

A
history of TB
TB contact
born in country with high TB prevalence
foreign travel
immunosupression
203
Q

Investigations?

A

3 Sputum cultures - acid fast, MC&S, PCR
Bloods: FBC, CRP, LFTs, HIV test
Imaging:
CXR, MRI if suspect military TB spread

204
Q

Diagnostic tests for TB?

A

Quantiferon test

Measures IFN-Y production after patient lymphocytes incubated with TB antigens

205
Q

TB Tx?

A
2 months RIPE
R = rifampicin
I = isoniazid
P= pyrazinamide
E = ethambutol

4 months of RI
Rifampicin & isoniazid

206
Q

Why so many TB medications?

A

Reduce resistance, Directly Observed Therapy

207
Q

Preventing TB?

A

BCG vaccine = attenuated liver Bovine TB

208
Q

Public health regulations about TB?

A

Notifiable disease
Contact tracing - 3 months prior
Isolation in hospital
DOT if uncomplient/homeless

209
Q

TB is associated with..?

A

HIV
Overcrowding
Asians
Malnutrition

210
Q

What is Bronchiectasis?

A

chronic infection of bronchioles and bronchi - causing permanent airway dilatation and retention of inflammatory secretions leading to recurrent infections

211
Q

Causes of bronchiectasis?

A

Congenital - CF
Post-infection - TB, pneumonia, Whooping cough
Inflammatory - RA, UC

212
Q

Symptoms of Bronchiectasis?

A

Purulent cough
haemoptysis
fever
weight loss

213
Q

Sign of Bronchiectasis?

A

clubbing
wheeze
fine inspiratory crepitus

214
Q

investigations of bronchiectasis?

A

Sputum MC&S
Bloods - FBC, immunology, blood cultures
Imaging - CXR - thickened bronchiole walls, hyper inflated lungs
Spirometry & CT sweat test (measuring level of chloride in sweat)

215
Q

Bronchiectasis Tx?

A

Chest physio
ABx - 14 days co-amoxiclav and flucloxacillin
Bronchodilators

216
Q

What is pleural effusion?

A

build up of fluid in pleural space between lungs and chest wall

217
Q

Risk factors for lung cancer?

A

Smoking
Age
FHx
Exposure to radiation or asbestos

218
Q

Types of lung cancers?

A
Small Cell Carcinoma - presents late and mets early
Non-small cell:
Squamous cell
Adenocarcinoma
Large cell
219
Q

Clinical features of lung cancer?

A
SOB
Chronic cough with heamptysis
Hoarseness
Weight loss
Fatigue
chest pain
220
Q

Signs of lung cancer?

A
clubbing
supraclavicular/axillary LNs
anaemia,
Horners
Pleural effusions
221
Q

Investigations for Lung cancer?

A

Bloods - FBC, U&Es, Lung function test, bone profile
Imaging:
CXR, staging CT (TNM), PET-CT as detects mets

Biopsy - bronchoscopy, thoracoscopy

Pleural fluid aspiration
Lung function test

222
Q

Complications of LC?

A

Local: recurrent laryngeal nerve palsy, phrenic nerve palsy, SVC obstruction, AF, Horners syndrome

Distant:
mets to bone
compression of VC - weak legs, back pain, loss off sensation, NM problems

Liver - hepatomegaly
Brain - confusion
Adrenal gland - addison’s

Paraneoplastic:
MSK - clubbing
Peripheral neuropathy
Anaemia
Endo:
Raised Ca - PTHrp
SIADH
Cushings - ATCH
223
Q

LC Tx?

A

Curative vs Palliative

Surgery
Chemo
Radio

224
Q

Stages of LC?

A

1 - small, localised to 1 area
2&3 - larger and growth to LNs
4 - distant metastasis

225
Q

TMN of LC?

A

T1 - within lung 1 cancer in same lobe

N0 - no LNs
N1 - nearest node
N2 - same side of mediastinum
N3- opposite side/supraclavicular

M0/1

226
Q

How to obtain a biopsy of lung?

A

Bronchoscopy with needle or surgical biopsy

227
Q

What type of LC is worse?

A

Small cell

228
Q

What causes pleural effusions?

A

Exudate from increased capil. permeability - cancers, pneumonia, TB, inflam. (RA, SLE)

Transudate: increase hydro. or reduced oncotic pressure
PE, HF, CKD, liver failure

229
Q

Investigations for pleural effusions?

A

Bloods: FBC, U&Es, LFT, CRP
CXR: blunt costophrenic angle, meniscus sign, mediastinal shift

US-guided pleural aspirationL colour, biochem (pH LDH, proteins, glucose), cytology, microbiology,

230
Q

What are different types of pleural effusions?

A

Haemothorax - blood
Empyema - pus
Chylothorax - lymphatic fluid
Simple effusion - serous fluid

231
Q

What are interstitial lung diseases?

A

disorders affecting lung parenchyma (between capillaries and alveoli) - contains fibrous tissue, cells of fluid

232
Q

Causes of ILD?

A
Occupation - asbestos, silica
Iatrogenic - methotrexate, chemo
Inflammatory - RA, SLE
Idiopathic
Infection - TB
233
Q

Symptoms of ILD?

A
SOB
Progressive dry cough
Coarse inspiratory crackles
Abnormal CXR - shadowing
Restrictive spirometry
234
Q

Investigations for ILD?

A

Bloods - FBC (eosinophilia), immunology, CXR, spirometry

235
Q

ILD Tx?

A
Underlying cause
High dose steroids
O2 therapy
analgesics
X smoking
236
Q

Talk about asbestos exposure?

A

Causes asbestosis, mesothelioma, pleural plaques, pleural thickenings, pleural effusions

237
Q

Mesothelioma signs?

A

Chest pain, weight loss, SOB, recurrent pleural effusions

CXR - pleural effusions, thickenings
Pleural biopsy

238
Q

What is extrinsic allergic alveolitis?

A

exposure to inhaled allergen causing reaction.

Inspiratory crackles
wheeze
No finger clubbing
Micro nodules

Acute - sudden onset within hours, reversible spont. / with tx

Chronic - less reversible

239
Q

Causes of allergic alveolitis?

A

bird fanciers - droppings

mouldy hay with farmers - aspergillus

240
Q

What is a pneumothorax?

A

air trapped in pleural space - associated with trauma

241
Q

What is a tension pneumothorax?

A

tracheal shifts AWAY from pneumothorax

242
Q

CXR - calcified plaques?

A

Asbestos exposure

243
Q

Hyperinflation?

A

COPD - blunting of costophrenic angles and hemidiaphragms

244
Q

Pneumoperitoneum?

A

Bowel perforation with air seen under the diaphragm

245
Q

CXR - cardiomegaly?

A

Over 50% the width of the thorax (measuring from widest past of heart and ribcage laterally)

246
Q

Why is it harder to breath with ILD?

A

Fibrosis is restrictive deficit, resistance not increased, lengthened diffusion pathway

247
Q

What is fibrosis alveolitis?

A

Progressively inflammatory condition - activated alveolar macrophages attracting neutrophils and eosinophils, damaging lung with proteases and ROS leading to fibrosis.

Finger clubbing, SOB, non-productive cough, micro-nodules on CXR.

Tx - high dose steroids

248
Q

What is sarcoidosis?

A
non-caseasting granuloma
idiopathic
fluid in always and lots of cells in the alveoli
diffuse fibrosis
genetic predisposition
Features - asymptomatic, cough & SOB
Tx - steroids
249
Q

What is pleurisy/ pleuritis?

A

Inflammation of pleura

250
Q

Signs of pleurisy?

A

Sharp pain on inspiration and pleural rub - creaking noise in steph. with resp. movements

251
Q

Causes of pleurisy?

A

Infection - TB, pneumonia

Autoimmune - SLE, RA

Lung cancer
Pneumothorax
PE

252
Q

Chest wall abnormalities?

A

scoliosis
kyphosis
broken ribs –> pneumothorax

253
Q

Muscle and neuro disease?

A

Muscular dystrophy
Motor neurone disease
polio

At risk of resp. failure, and infections