Term
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Definition
| The stopping or slowing of breathing whilst asleep due to obstruction of the upper respiratory tract. |
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Term
| Who is most at risk of developing sleep apnoea? |
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Definition
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Term
| What structural changes may cause sleep apnoea? |
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Definition
| Obesity, narrow pharyngeal opening, facial shape and tonsil/nasal problems. |
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Term
| What diseases predispose you to sleep apnoea? |
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Definition
| COPD, diabetes, hypothyroidism, acromegaly and neuromuscular disease/stroke. |
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Term
| What pharamcological changes may predispose you to sleep apnoea? |
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Definition
| Alcohol, smoking, sedation and anti-depressants. |
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Term
| Why do patients not suffocate with sleep apnoea? |
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Definition
| Increased PaCO2 causes enough arousal for the palate and tongue to increase tone enough to open the airway again. |
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Term
| What are the symptoms of sleep apnoea? |
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Definition
| Loud snoring, day time sleepiness, apnoea/restless sleep noticed by partner, head aches, loss of libido, night sweats, choking etc. |
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Term
| What is the Epworth sleepiness scale? |
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Definition
Intended to measure day time sleepiness,e.g likeliness to fall asleep when reading.
o Score out of 3 for each question. Total of 10-15 = mild/ moderate sleep apnoea. >15 = severe sleep apnoea/ narcolepsy |
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Term
| What is Cheyne-stokes respiration? |
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Definition
| Progressively deeper and sometimes faster breathing, followed by a gradual decrease that results in a temporary stop in breathing called an apnea |
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Term
| How might overnight oximetry tracing aid in the diagnosis of OSA? |
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Definition
| Pattern of regular desaturation shown and can be combined with thoracic/abdominal movement allowing for differentiation of OSA and CNA causes of apnoea. |
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Term
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Definition
| Uses EEG, electrooculograms, EMG, ECG, pulse oximiters to measure muscle movement |
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Term
| How many episodes of apnoea are required for a diagnosis of OSA? |
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Definition
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Term
| How do you manage a diagnosed OSA? |
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Definition
| CPAP, posture training, lifestyle advice and treating underlying disorders. |
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Term
| What are the driving rules associated with OSA? |
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Definition
| Patient must inform DVLA of diagnosis, confidentiality must be breached if patient refuses. |
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Term
| If OSA reamins untreated, what is the prognosis? |
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Definition
Effects: Personality changes, Sleep-related job problems, Relationship & Sex dysfunction
↑ Risk Of: Cardiac problems – commonest secondary cause of hypertension, Depression etc., Sudden Death |
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Term
| Define respiratory failure? |
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Definition
| Inadequate gas exchange resulting in an inability to maintain arterial O2/ CO2 in normal ranges. |
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Term
| Define Type 1 respiratory failure |
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Definition
| Hypoxia without hypercapnia |
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Term
| What are the most likely acute causes of Type 1 respiratory failures? |
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Definition
| Typically low ventillation/perfusion ratio (V/Q ratio) e.g. oedema, pneumonia, blood. Low ambient oxygen, PE, ARDS. |
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Term
| What are the most likely chronic causes of Type 1 respiratory failures? |
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Definition
| Pulmonary oedema and emphysema |
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Term
| What is Type 2 respiratory failure? |
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Definition
| Hypoxia with hypercapnia. pH low and HCo3 High or normal. |
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Term
| What are the likely causes of type 2 respiratory failure? |
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Definition
Pulmonary e.g- OSA, asthma, obesity, fibrosis.
Thoracic wall e.g- Flail chest, kyphoscoliosis
CNS e.g- Head injuries, stroke, tumour, neck injury (C3,4,5)
Neuromuscular e.g- Acid maltase deficiency (pompe disease), myesthenia gravis and guillan barre. |
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Term
| What are the clinical features of hypoxia? |
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Definition
| Dyspnoea/tachypnoea, restlessness, agitation, confusion and central cyanosis. |
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Term
| What are the clinical features of hypercapnia? |
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Definition
| Headache, papilloedema, peripheral vasodilation, tachycardia, bounding pulse, tremor/flap, confusion and drowsiness |
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Term
| Where does ventilatory rhythm originate? |
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Definition
Medulla oblongata.
N.B Coning occurs with raised inracranial pressure resulting in compression of the medulla oblongata and therefore respiratory depression. |
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Term
| What medullary regions initiate respiratory muscle impulses? |
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Definition
pFRG (Parafacial Respiratory Group) initiates action potential before inspiration
DRG (dorsal respiratory group)Originate action potential during inspiration
VRG (ventral respiratory group)originates action potential during expiration. |
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Term
| What is the role of the pontin respiratory group (PRG) in the pons in respiration? |
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Definition
| Fine tuning of breathing rhythm and volume inspired/expired. |
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Term
| Where is the inspiratory rhythm likely to originate? |
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Definition
| pre-Botzinger Complex (pBC) within the VRG. |
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Term
| Where is expiratory rhythm likely to originate? |
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Definition
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Term
| Where does the control of voluntary breathing originate? |
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Definition
| Cerebral cortex and down pyrimidal tracts therefore bypassing medulla allowing unconcious breathing. |
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Term
| Central chemo receptors would detect a change in what allowing for stimulation of change in breathing? |
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Definition
| Carbon dioxide increase and hydrogen levels |
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Term
| Peripheral chemo receptors would detect a change in what allowing for stimulation of change in breathing? |
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Definition
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Term
| Where are central chemoreceptors found? |
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Definition
| Ventro-lateral medullary surface |
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Term
| How do central chemoreceptors detect a change in CO2? |
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Definition
| CO2 diffuses from cerebral capillaries into CSF and dissociates into carbonic acid. Central chemoreceptors bathed in carbonic acid. This is slow reacting |
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Term
| Where are peripheral chemoreceptors situated? |
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Definition
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Term
| What stimulates peripheral chemoreceptors? |
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Definition
| PaO2 below 60mmHg, alos monitor PaCO2 levels. |
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Term
| What is the role of Glomus cells? |
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Definition
| Responsible for chemoreception and release neurotransmitters to to stimulate resp centres in medulla. Fast reacting response. |
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