WEEK 7 Flashcards
What is palliative care?
Improves the quality of life of pts & their families facing the problem(s) associted with life-threatening illness
- through the prevention & relief of suffering by means of early identification & impeccable assessment & treatment of pain & other problems (physical, psychosocial & spiritual)
What are the principles of delivering good end of life care? (HINT: there’s 6 points)
- Open lines of communication
- Anticipating care needs & encouraging discussion
- Effective multidisciplinary team input
- Symptom control - physical & psycho-spiritual
- Preparing for death - pt & family
- Providing support for relatives both before & after death
What are the areas for discussion during advance and anticipatory care planning? (HINT: there’s 7 areas)
- Wishes/preferences/fears about care
- Feelings/beliefs/values that may influence future choices
- Who should be involved in decision making?
- Emergency interventions e.g. CPR
- Preferred place of care
- Religious/spiritual/pther personal support
- May wish to make Advance & Anticipatory care plan/formalise wishes regarding care
What is the framework for assessing the validity of advance care decisions?
- Is it clearly applicable?
- When was it made?
- Did the patient have capacity when it was made?
- Was it an informed decision?
- Were there any undue influences when made?
- Has the decision been withdrawn?
- Are more recent actions / decisions inconsistent?
How important is good quality care in the last days or hours of life?
- Informative, timely & sensitive communication is an essential component of each individual person’s care
- Significant decisions about a person’s care, including `diagnosing dying, are made on the basis of multidisciplinary discussion
- Each individual person’s physical, psychological, social and spiritual needs are recognised and addressed as far as is possible
- Consideration is given to the wellbeing of relatives or carers attending the person
role of a medical history in making a clinical diagnosis
- Forms a differential diagnosis & put health in context
- Identify risk factors for conditions
- Red Flags
- Direct further clinical examination
- Direct investigation & management
- Develop a rapport between pt & healthcare worker
how to take a detailed drug history
For each drug, in turn
- name of medicine?
- do you know what it is for?
- what is the dose/strength?
- what is the route
- number of tablets or puffs or dose units taken?
- type/form - device type?
- how often do you take this?
- any recent changes to dose/frequency?
What is a useful mneumonic for asking all the clarifying chest pain questions?
SOCRATES
- site
- onset
- character
- radiation
- associated symptoms
- timing
- exacerbators/relievers
- severity (1-10 rating scale)
What are specific respiratory questions asked?
- Chest Pain
- SOCRATES - Dyspnoea
- Cough
- how long had it, when occur
- anything make better or worse
- dry cough? cough anything up? - Sputum
- how often produced? How much? colour? blood? frothy or thick? smell? - Haemoptysis
- how much blood? any other colours? any breeding or bruising? taking blood thinners? - Wheeze
- Systemic upset
What are the respiratory causes of dyspnoea?
Airways - asthma, COPD, bronchiectasis, cystic fibrosis, larygeal tumour, foreign body, lung tumour Parenchyma - pneumonia, pulmonary fibrosis, sarcoidosis, TB Pulmonary Circulation - PE Pleural - pneumothorax, pleural effusion Chest Wall - kyphoscoliosis, ankylosing spondylitis Neuromuscular - myasthenia gravis, Guillain-Barre syndrome
What does an (i) acute cough (ii) chronic cough suggest?
(i) viral or bacterial infection pneumonia inhalation of foreign body irritants (ii) common = gastro-oesophageal reflux, asthma, COPD, smoking, post-nasal drip, occupational/other irritants, medication (ACEI)
What causes an (i) acute cough (ii) chronic cough?
(i) viral or bacterial infection
pneumonia
inhalation of foreign body
irritants
(ii) common = gastro-oesophageal reflux, asthma, COPD, smoking, post-nasal drip, occupational/other irritants, medication (ACEI)
less common = lung tumour, bronchiectasis, interstitial lung disease
What are the causes of central chest pain? (HINT: there’s 7)
tracheitis angina/MI aortic dissection massive PE oesphagitis lung tumour/metastases mediastinal tumour/mediastinitis
What are the causes of non-central (i) pleural (ii) chest wall pain?
(i) pneumonia/bronchiectasis/TB lung tumour/metastases/mesothelioma PE pneumothorax (ii) muscular/rib injury costochondritis lung tumour/bony metastases/mesothelioma shingles
What are the conditions associated with dyspnoea that onsets in minutes? (HINT: there’s 5 conditions)
PE Pneumothorax Acute LVF Acute asthma Inhaled foreign body
What are the conditions associated with dyspnoea that onsets in hours to days? (HINT: there’s 3 conditions)
Pneumonia
Asthma
Exacerbation of COPD
What are the conditions associated with dyspnoea that onsets in weeks to months? (HINT: 3 conditions)
Anaemia
Pleural effusion
Respiratory neuromuscular disorders
What are the conditions associated with dyspnoea that onsets in months to years? (HINT: 3 conditions)
COPD
Pulmonary fibrosis
Pulmonary TB
What is the appearance & cause of serous sputum?
Clear, watery, frothy, pink
- acute pulmonary oedema
What is the appearance & cause of mucoid sputum?
Clear, grey, white, viscid
- COPD/asthma
What is the appearance & cause of purulent sputum?
Yellow, green, brown
- infection
What is the appearance & cause of rusty sputum?
Rusty red
- pneumococcal pneumonia
What is 2 examples of malignant haemoptysis?
bronchial carcinoma
metastatic lung disease
Name 3 examples of infective haemoptysis?
acute infection
bronchiectasis
TB
Name 2 examples of vascular haemoptysis?
Pulmonary infarction
Pulmonary embolus
Name 2 examples of cardiac haemoptysis?
mitral valve disease
acute LVF
Name 2 examples of vasculitis haemoptysis.
Wegener’s granulomatosis
What are 3 other examples of haemoptysis that don’t come under any specific sub-category.
trauma
anticoagulation (warfarin)
clotting disorder
What are 4 reasons for unintentional non-concordance with regards to drug taking?
- Physical dexterity
- Reduced vision
- Cognitive impairment
- Poor understanding
What is the difference between a blue & brown inhaler?
BLUE “reliever”
- salbutamol
BROWN “preventer”
- beclomethasone
What structures form the (i) conducting (ii) respiratory tract?
(i) nasal cavity nasopharynx oropharynx larynx trachea main bronchi lobar bronchi segmental & terminal bronchioles (ii) respiratory bronchioles alveolar ducts alveoli
What is the structure & function of the trachea?
10-11cm long & 12 mm’s wide internally
Palpable above suprasternal notch
starts C6 ends T4/5
C-shaped rings of hyaline cartilage supporting a fibro-elastic & muscular air-transport tube
What is the NVS of the trachea? What are the relations of the trachea?
Arteries = inf. thyroid & bronchial Veins = inf. thyroid Lymph = pre & para tracheal Nerves = vagi, recurrent laryngeal, sympathetic trunks
LRLN lies in groove between trachea & oesophagus
R. vagus, azygous & R. brachiocephalic vein lie to the right, L. common carotid lies to left.
How does the epithelium of the bronchial tree change as they branch into the lungs?
terminal bronchioles = smallest part of conducting portion.
Beyond, passage becomes increasingly involved in gaseous exchange
Respiratory bronchioles have a few alveoli coming off walls & no goblet cells w. cuboidal epithelial cells
- give rise to several alveolar ducts which branch into alveolar sacs & finally alveoli
What is the structure & function of the right & left lung?
R = 3 lobes L = 2 lobes
1/2 cone shaped
Anterior, posterior & inferior borders
Costal, diaphragmatic & mediastinal surfaces
Oblique (T4 spine - 6th rib) & horizontal (rib4/5) fissures
L. lung smaller than R
What are the relations of the (i) right (ii) left lung?
(i) RA, SVC, azygous vein (posteriorly)
(ii) Aorta, LV forming cardiac notch
Phrenic nerves pass ant. to lung roots & vagus pass posterior
main bronchus posterior (1L, 2R)
PA anterior & superior (1L, 2R)
Pulmonary veins anterior & inferior
What is the blood supply of the lungs?
PA arise from PT just below sternal angle. Carry de-oxy blood at low pressure to lungs
R. PA longer than left & passes anterior to bifurcation of trachea & R. primary bronchus. Lies posterior to asc Ao & SVC
L. PA shorter & anterior to desc Ao
PV carry blood back to LA
Bronchial arteries supply lung tissue
List the different ways tumours can affect the lungs.
On both sides:
1. Tumour may impinge upon phrenic nerve to cause paralysis of the diaphragm on the affected side
2. Tumour may impinge upon the sympathetic trunk & embarrass sympathetic supply to the head causing Horner’s Syndrome, which is a drooping eyelid with a constricted pupil & a dry but flushed face on the affected side
On the left side only:
- tumour (or affected lymph nodes) may impinge upon the recurrent laryngeal nerve to cause hoarseness of the voice
What does the (i) single R. bronchial artery (ii) 2 L. bronchial arteries arise from?
(i) 3rd posterior intercostal artery
(ii) aorta directly
When might the trachea deviate from the midline?
By a tension pneumothorax
What are the various bronchopulmonary segments of the right lung? (HINT: there’s 10 segments)
UPPER LOBE - apical, anterior & posterior MIDDLE LOBE - medial, lateral LOWER LOBE - apical, anterior, posterior, medial, lateral
What are the various bronchopulmonary segments of the left lung? (HINT: theres 8-10 segments)
UPPER LOBE - apical, anterior & posterior LINGULA - superior & inferior LOWER LOBE - apical, anterior, medial, lateral, posterior
Describe the features of bronchopulmonary segments.
Pyramid with its base on the surface of the lung & apex pointing to the hilum
- they are separated from each other by connective tissue
- disease may be confined within a segment, but can be removed surgically
Identify the structures in the hilum of the lung.
Main bronchus is posterior (1L, 2R)
PPA is anterior AND superior (1L, 2R)
2 pulmonary veins are anterior & inferior
Lymphatics and hilar lymoh nodes, nerves, bronchial vessels
What is the pulmonary ligament?
a fold of pleura (like a coat sleeve) that allows hilar movement during respiration and vessel expansion
What anastomoses occurs in the lungs?
Bronchial arteries may anastomose with PAs in the walls of the bronchioles,=> some blood supplied by the bronchial arteries drains into the pulmonary veins
- Bronchial veins themselves drain into the azygos system
What is the lymphatic drainage of the lungs?
deep lymphatic plexus running alongside the arteries and the dividing bronchial tree; plus a superficial or sub-pleural plexus of lymphatics. They converge on pulmonary nodes which merge & drain to bronchopulmonary nodes, which then merge with and drain to paratracheal nodes and R. and L. bronchiomediastinal lymph trunks
- R. usually joins R. lymphatic trunk & L joins thoracic duct
What is the nerve supply of the lungs & pleura?
Supplied by pulmonary plexuses that lie anterior & posterior to the main bronchi at root of lung
- PS fibres from vagus synapse in plexuses: postganglionic fibres are bronchocontrictor, vasodilator & secretomotor
- S synapse in sympathetic ganglio, post ganglionic are bronchodilator, vasoconstrictor
- pain fibres travel with symp
VISCERAL pleura - no general sensory supply
PARIETAL pleura = sensory fibres from intercostal and phrenic nerves (referred pain)
What is involved in the close inspection & palpation of the respiratory exam?
Examine hands - inspect, palpate for warmth & venodilation, flapping tremor & fine tremor, palpate radial pulse (rate & rhythm)
Count respiratory rate
Inspect face, eyes, mouth & pharynx
What are the respiratory causes of clubbing?
Bronchial carcinoma Mesothelioma Chronic suppurative lung disease - bronchiecstasis, lung abscess, empyema Pulmonary fibrosis Cystic fibrosis
What is Horner’s syndrome? What are the clinical features of Horner’s syndrome?
Damage to cervical sympathetic nerves
Clinical features:
- unilateral miosis, partial ptosis, loss of sweating on same side (facial anhidrosis)
What are the 2 types of hand tremor? What do they result from?
FINE TREMOR - excessive use of beta agonists FLAPPING TREMOR - severe ventilatory failure with CO2 retention - hold hands outstretched - wrists cocked-back - look for a jerky, flapping tremor - associated confusion
When doing a close inspection of chest/neck of respiratory system, what are you looking for?
Scars - cardiac surgery, thoracotomy, chest drain scars
Pattern of breathing
Shape of chest - symmetry, deformity, increase in A-P diameter
Prominent veins on chest wall - SVC obstruction
JVP
What is involved in the palpation of the chest & neck in a respiratory exam?
Lymph nodes
Subcutaneous ('surgical') emphysema
- crackling sensation
- air in subcutaneous tissues
- may be diffuse chest, neck & face swelling
Mediastinal position
- tracheal position
- cardiac apex
Chest expansion
- anterior and posterior
- ask pt to breath deeply and thumbs should move apart equallyWhat is involved in the percussion stage of a respiratory examination?
Anterior AND posterior chest
Use middle finger/L. hand
- percuss over intercostal spaces, compare L AND R
- listen to note produced
What are examples of possible causes of the percussion note (i) resonant (ii) hyper resonant (iii) dull (iv) “stony” or very dull
(i) normal lung
(ii) emphysema, large bullae or pneumothorax
(iii) collapse, consolidation or fibrosis
(iv) pleural effusion
What are the 2 types of breath sounds?
NORMAL - vesicular
- intensity of sounds relates to airflow
- diminished vesicular breath sounds (obesity, pleural effusion, pneumothorax, collapse, hyperinflation in COPD)
BRONCHIAL - high pitched
- consolidation with patent bronchial system (pneumonia, top of pleural effusion, pulmonary fibrosis)
What are the 3 types of added sounds that can be heard upon auscultation? What are the causes of each type?
- CRACKLES (crepitations)
- pulmonary oedema, pulmonary fibrosis, bronchial secretions, COPD, pneumonia, lung abscess, TB, bronchiolitis, bronchiectasis - PLEURAL RUB
- PE, pneumonia, vasculitis - WHEEZE
- implies airway narrowing, is louder in expansion
- asthma, COPD, lung tumour (localised)
What are the 2 ways to test vocal fremitus/resonance? What are the potential outcomes of this test?
VOCAL FREMITUS
- use palm/ulnar border of hand
VOCAL RESONANCE
- use stethoscope
Increased resonance in consolidation or fibrosis
Decreased resonance in pleural effusion or collapse
What are the other areas that are to be included in a respiratory examination? (HINT: there’s 5)
- ankle oedema
- sputum pot
- observation chart
- peak flow
- spirometry
Describe the anatomy of the sternum.
Sternal angle of louis at T4/5 and 2nd CC
Articulates ribs 1-7
Symphysis i.e. fibrocartilage that should never ossify and therefore allow respiratory movement
Describe the anatomy of a typical rib.
Head, neck, tubercle, angle, body/shaft
2 articular demi-facets at rib head - tubercle also has a facet (flat in ribs 8-10 and convex in rest)
Costal groove on inner surface and close to inferior border (which is sharper than superior border)
Describe the anatomy of a thoracic vertebrae
Heart shaped body and circular vertebral canal
Long overlapping spinous processes
Body with sup and inf demifacets for articulation with the heads of 2 pairs of ribs
Transverse processes that articulate with the tubercles of a pair of ribs
Sup and inf articular facets that allow some rotation (NO flexion)
How do the ribs, vertebrae, costal cartilages & sternum form the “thoracic cage”? Give particular reference to the anterior and posterior articulations of the ribs
CC1 and sternum form a primary cartilaginous (hyaline) joint making the thoracic inlet more stable
What is the structure and function of the intercostal musculature?
Support intercostal space and prevent in-drawing during inspiration
Supplied by intercostal nerves T1-11
EXTERNAL: fibres down & medial. From inf. rib edge to sup ridge edge below. Anteriorly are ext. intercostal membrane. Raise ribs in INSPIRATION
INTERNAL: fibres down and lateral. From lat. edge costal groove to sup. edge rib below. Posteriorly is int. intercostal membrane. Aids elastic recoil by moving ribs inf. in EXPIRATION
INNERMOST: act with int. intercostals
What is the arterial supply of the intercostal spaces (and breast)?
ARTERIAL SUPPLY Anterior: 1. Internal thoracic: branch of 1st part of SC, lies along sternal margin and terminates as sup. epigastric and musculophrenic arteries. Also supplies medial 1/2 breast. 2. Anterior intercostal arteries - 2 per space in spaces 1-6 - 7-10 from musculophrenic - 11 and 12 no supply Posterior: 1. 1st part SC Artery - supplies 1st 2 spaces via supreme intercostal artery 2. Thoracic Aorta - 9 pairs posterior intercostal arteries - 2 per space in 3-11 - 12th branch is subcostal artery
What is the lymphatic drainage of the intercostal spaces (and breast)?
Anteriorly drains to parasternal nodes
- these lie alongside internal thoracic (mammary) artery and drain into the bronchomediastinal trunks
Posteriorly drains to intercostal nodes
- these lie on the heads of ribs and drain to either to thoracic duct (inferiorly) or to bronchomediastinal trunks
superiorly
What is the nerve supply of the intercostal spaces (and breast)?
?
What structures must a needle pass through when inserting a chest drain?
skin
pec major (possibly minor depending on site)
external, internal and innermost intercostal muscles
endothoracic fascia
parietal pleura
What type of joint is the (i) joint between rib and CC (ii) joint between CC and sternum of ribs 1-7?
(i) primary cartilaginous (hyaline)
ii) synovial (except CC1 which is primary cartilagenous
What type of joint is the (i) joint between rib and CC (ii) joint between CC and sternum of ribs 1-7?
(i) primary cartilaginous (hyaline)
ii) synovial (except CC1 which is primary cartilaginous
What is the venous supply of the intercostal spaces (and breast)?
ANTERIOR intercostal veins
- venae comitantes of the int. thoracic artery and its ant. intercostal arteries drain to the int. thoracic vein
POSTERIOR intercostal veins
- 1st space drains to BCV
- 2nd & 3rd form sup. intercostal vein
- on R. drains arch azygous & on L. to the BCV
- all others drain to azygous
What is the venous supply of the intercostal spaces (and breast)?
ANTERIOR intercostal veins
- venae comitantes of the int. thoracic artery and its ant. intercostal arteries drain to the int. thoracic vein
POSTERIOR intercostal veins
- 1st space drains to BCV
- 2nd & 3rd form sup. intercostal vein
- on R. drains arch azygous & on L. to the BCV
- all others drain to azygous
What is the arterial supply of the breast?
Int. thoracic and its anterior intercostal branches
- mainly from superior thoracic thoraco-acromial and lateral thoracic branches of the axillary artery
What are the 3 levels used to define the severity for tumour spread into the axillary nodes?
LEVEL 1 anterior/pectoral group (lat to P. min)
LEVEL 2 central (deep to P. min)
LEVEL 3 apical group (med to P. min)
What are the 3 levels used to define the severity for tumour spread into the axillary nodes?
LEVEL 1 anterior/pectoral group (lat to P. min)
LEVEL 2 central (deep to P. min)
LEVEL 3 apical group (med to P. min)
What is the intercostobrachial nerve? When is it at risk of damage?
Derived from T2
Large lateral cutaneous branch that supplies the thorax wall in axilla and upper. medial part of UL
- at risk in breast surgery
What are the key arguments often cited for/against the use of animals in research?
Benefits Model Sentience (how aware animal is, intelligence) Value Moral agency Spiritual/religious potential Human achievement
What are the three principles governing the use of animals in research (from the Home Office policy)?
- REPLACEMENT
- e.g. alternative technologies, use lower organisms - REDUCTION
- e.g. better study design to allow use of fewer animals; better storage of data - REFINEMENT
- e.g. improve housing, minimise pain, improve welfare
What is the regulatory role of the Home Office in animal research, and the National Research Ethics Service (NRES) & local ethics committees in human research?
Review and monitor all eligible research, using ASPA and Home Office guidelines
Licenses are granted (site, personal or project)
- within each local arena there’s an animal ethics committee that review and monitor all eligible research using ASPA and home office guidelines
Debate the need for transparency in publication authorship and declaration of conflicts of interest.
Authorship
Conflicts of interest
The area of reproducibility (or lack thereof)
What are the different ethical issues raised by the Tuskegee Syphilis trial, the Guatemalan STD trial, and the case of Henrietta Lacks?
Tuskegee Syphilis Trials
- lasted 40 years
- were told being treated for “bad-blood” but not treatment
- incentives were used and they weren’t allowed to be treated in clinics/hospitals in area.
Guatemalan STD Trials
- no evidence that consent was sought
- exposed pts to gonorrhoea, syphilis or chancroid deliberately
Henrietta Lacks
- cells from her cervix cultured in vitro and 1st immortal human cell HeLa
- she died from cervical cancer and her cells were used in various research with no consent from her or her family
Justification = material was no longer “hers” and would have been thrown away
Debate the need for transparency in publication authorship and declaration of conflicts of interest.
Authorship
Conflicts of interest
- e.g. financial ties, academic commitments, personal relationships, religious or political beliefs, institutional affiliations
The area of reproducibility (or lack thereof)
What is the function of the nose and nasal cavity?
warm, humidify & filter inhaled air
sense of smell - olfaction
What are the nostrils (nares) supported by anteriorly?
Hyaline septal, lateral and alar cartilages that are moveable
What is the function of muscles around the nostrils?
Act as sphincters or dilators to control the diameter of the nares and adjust air flow
What are the bones of the (i) roof (ii) lateral wall?
(i) nasal, frontal, ethmoid, sphenoid
(ii) nasal, maxilla, lacrimal, ethmoid, palatine, med. pterygoid plate of sphenoid
Describe the conchae (turbinates).
Increase s.a and create turbulence in inhaled air
They are covered by highly vascular mucous membrane
What is the nasal septum? What complications can arise?
Lies in the midline, it is bone posteriorly and cartilage anteriorly
- the septum may deviate from the midline and compromise sinus drainage
What can cause CSF rhinorrhoea?
fracture of the cribriform plate
What is the olfactory epithelium restricted to?
the cavity roof and the adjacent lateral wall and septum
What is the nerve supply of the (i) lateral wall (ii) medial wall of the nasal cavity?
all derived from the opthalamic and maxillary branches of the trigeminal nerve = Cranial V1 and V2
(i) 1. anterior, superior (lateral) nasal nerves from V1 mainly via ant. ethmoidal nerve
2. Posterior, inferior (lateral) nasal nerves from V2 mainly via greater palatine nerve
(ii) 1. anterior, superior (medial) nasal nerves from V1
2. posterior, inferior (medial) nasal nerves from V2 mainly via nasopalatine nerve
Describe the high vascularity of the nasal mucous membrane.
Vessels form an anastomosis between the left, right, internal and external carotids
What are the 3 skeletal elements of the medial wall of the midline septum?
vomer
perpendicular plate of ethmoid
septal cartilage
What is the arterial supply of the septum?
Essentially septal branches from the maxillary and ophthalmic arteries, just like the lateral wall
If the palatine canal is dehiscent what can this predispose?
severe epistaxis form the greater palatine artery
What does the (i) maxillary sinus (ii) sphenoid sinus (iii) nasolacrimal duct (iv) posterior ethmoidal cells open into?
(i) hiatus semilunaris (posteriorly)
(ii) speno-ethmoidal recess
(iii) inf. meatus
(iv) superior meatus
What is the lymph drainage of the nasal cavity?
Anteriorly = submandibular nodes Posteriorly = retropharyngeal nodes to the upper deep cervical nodes
What is the larynx?
a protective sphincter that prevents foreign bodies entering the airways
Laryngeal elevation is crucial to swallowing
What are the tonsils?
Protective clusters of lymphoid tissue; mucous membrane forms crypts
- they form a protective (waldeyer’s) ring around the openings of the respiratory and GI tracts
What does (i) inflammation and swelling of pharygeal tonsil (ii) enlargement of the tubal tonsil cause?
(i) obstruct the airway and lead to mouth breathing
(ii) may obstruct the pharyngotympanic tube and cause middle-ear infections
What is the lymph drainage of the tonsils?
To the jugulodigastric node
- palpable behind the angle of the mandible
What is the function of the (i) nasopharynx (ii) oropharynx?
(i) transports air, and is divided from the oropharynx by the soft palate
(ii) transports air plus food and fluid, but these must be separated so air passes into the larynx while food and fluid continue into the laryngo- pharynx
Where is the site of emergency access to the airway?
The median cricothyroid ligament
What are the names of the laryngeal cartilages? What are they composed of? What is their function?
Epiglottic (elastic) Thyroid Arytenoid Cricoid All hyaline cartilage except epiglottis They suspend and support the fibro-elastic, membranous tube
Describe the (i) cricoid (ii) thyroid
(i) signet ring with lamina posteriorly. It articulates with the arytenoids and the thyroid. “sloping shoulder” on the lamina for arytenoid articulation. Has a ridge for the attachment of the oesophagus and a depression for the attachment of the posterior crico-arytenoid m.
(ii) L. and R. laminae, each with superior and inferior horns (inf. articulates with cricoid). The laminae fuse anteriorly as laryngeal prominence (more obvious in males)
Describe the (i) epiglottis (ii) arytenoid.
(i) Attaches to the thyroid cartilage and projects upwards into the pharynx, behind the posterior part of the tongue
(ii) pyramidal shape, 3 sides and base that articulates with sloping shoulders of cricoid lamina. Is “topped” by corniculate and cunieform cartilages. Has a vocal process anteriorly for attachment of vocal lig/fold
What is the extrinsic Thyrohyoid membrane?
Spans the space from upper edges of thyroid lamina and superior horn to the upper edges of the body and greater horn of hyoid
Thickened anteriorly and posteriorly as the median and lateral thyrohyoid ligaments.
What are the 2 intrinsic membranes/ligaments?
- Quadrangular form arytenoid to thyroid and epiglottis
2. Cricovocal (cricothyroid) from the cricoid and arytenoid to the thyroid forms the conus elasticus
What are the 3 types of laryngeal folds? Describe where they are located.
1, ARYEPIGLOTTIC FOLD
- formed over aryepiglottic lig (i.e. upper edge of quadrangular membrane)
2. VESTIBULAR FOLD - over vestibular lig (lower edge quadrangular membrane)
3. VOCAL FOLD - over vocal lig. (upper edge cricothyroid membrane)
What is the laryngeal inlet? What forms the inlet? How is it closed?
The protective sphincter
Aryepiglottic folds on each side are the upper edge of quadrangular membrane
Closure by elevation of larynx - lifted up and forward during swallowing
What is the function of the vocal folds?
Control laryngeal diameter for:
speech, coughing, sneezing and raising intra-abdominal pressure which is vital in parturition (giving birth), micturition, defecation and lifting heavy objects
Where is the ventricle of the larynx? What is the function of the saccule?
Between the vestibular and vocal folds and leads to the saccule, which is to provide lubricating mucus for the vocal folds.
How are the aryepiglottic folds (laryngeal inlet) (i) closed (ii) opened?
(i) elevation of larynx and pharynx by extrinsic muscles from skull -> larynx and pharynx. Thyro-epiglotticus may help sphincteric affect by compressing vestibule and drawing epiglottis and arytenoids towards each other
(ii) descent of larynx mainly by elastic recoil
What is the movements of the arytenoid cartilages? What do these movements result in?
swivel (or externally rotate), and glide laterally down the shoulders of the cricoid lamina (abduct)
These movements combine to separate the vocal folds and open the rima glottidis to hugely variable degrees and positions
How are the vocal folds (rima glottis) opened and closed?
OPEN: posterior crico-arytenoid both swivels or externally rotates the arytenoids, as well as pulling them apart down the sloping shoulders of the cricoid (abduction)
CLOSE: arytenoids are pulled back up the cricoid shoulders towards each other (adduction) by transverse arytenoid and the cords are swivelled towards each other (internally rotated) by lateral crico- arytenoid
How are the vocal folds/ligaments lengthened and shortened?
SHORTEN: rocking thyroid back towards arytenoids: thyro-arytenoid
LENGTHEN: rocking thyroid forwards: cricothyroid
During (i) quiet inspiration (ii) forced inspiration what is the function of the larynx?
(i) all folds open and triangular rima, with cords abducted
(ii) rima more forcefully and widely opened by posterior crico-arytenoid externally rotating the arytenoids (rhomboid shaped opening)
What is phonation?
vocal folds are adducted to close the rima glottis and air is forced through, causing vibration Cord length and tension are altered by an interplay between cricothyroid, thyro-arytenoid and vocalis
What is the innervation of the larynx?
The Vagus sends the Sup. Laryngeal nerve, which passes with the sup. thyroid artery until it divides into int. and ext. branches.
Sensation of the larynx down to just above the vocal folds is by the internal branch.
Cricothyroid is supplied by the external branch
Recurrent Laryngeal supplies all muscles of the larynx (except cricothyroid) and sensation to the vocal cords and larynx below
What does (i) complete paralysis of RLN (ii) partial paralysis of RLN (iii) paralysis of external larngeal nerve cause?
(i) vocal fold in semi-abducted position. It vibrates so respiration noisy, hoarse voice but compensation by extra movement of opposite fold
(ii) vocal fold moves to midline (and even cross it) => bilateral partial paralysis is life threatening
(iii) may not be noticed or slight hoarseness. Good recovery due to hypertrophy of opposite cricothyroid
What is the vascular supply and lymph drainage of the larynx ABOVE the vocal folds?
Sup. laryngeal nerve
- which is accompanied by the superior laryngeal branch of the superior thyroid artery
Veins drain to superior thyroid vein
Lymph to upper deep cervical nodes
What is the vascular supply and lymph drainage of the larynx BELOW the vocal folds?
Recurrent laryngeal nerve
- accompanied by the inf. laryngeal branch of inferior thyroid artery
Veins drain to inferior thyroid vein
Lymph to lower deep cervical nodes
What is at risk in a tracheostomy? Why is said structure at risk?
Inferior thyroid veins
- as they descend to the left brachiocephalic vein
What are the 4 ways to STOP HCAI?
- MEASURE the problem
- surveillance - UNDERSTAND the problem
- epidemiology (where, when, who, how big, cost) - MANAGE the problem
- education, knowledge, management tools for the problem (audit, bundles) - PREVENT the problem
- interrupting transmission (SICPs, hand hygiene, vascular access devices), prevention strategies
What are the precautions taken for (i) contact transmission (ii) droplet transmission (iii) airborne transmission?
(i) single room if poss, gloves, aprons, disposable masks/eye protection if at risk of splashes
(ii) single room if poss, wear surgical mask when within touching distance (1metre) of pt or cough inducing procedure
(iii) single room, apron, gloves, high efficiency filter mask (FFP3 mask)
What is the appropriate hand hygiene?
“2 before and 3 afters”
Alcohol gel used if hands sociably clean
MUST use soap after exam of pt with diarrhoea
What is a (i) invasive medical device (ii) indwelling prosthetic device?
(i) may be long or short term and all break the mucous membrane barrier. E.g. CVC, PVC, urinary catheters, dialysis lines etc.
(ii) usually long term devices buried into tissue under the skin e.g. heart valves, joints, pacing units etc.
What is the difference between a HAI and a HCAI?
HAI = hospital associated infection
- one that wasn’t present on admission but occurred >48hrs after admission
HCAI = healthcare associated infection
Why is evidence based medicine is an important part of modern medicine?
It is a daily requirement for correct answers to questions about
- the effects of therapy
- utility of diagnostic tests
- prognosis of diseases
- etiology of disorders
What are the principles of EBM?
- High quality health care rests on objective and clinically relevant information
- There’s a hierarchy of evidence where some types are stronger than others
- Scientific data alone is not a sufficient bases for making clinical decisions about individual pts
What are the pros and cons of the EBM approach?
PROs:
- formalises that old hat and filters literature so decisions made on strong evidence
- only one part of decision making process (clinical expertise, pt preferences and good evidence)
- produces expert judgement in a format that clinicians can understand
- last step is to decide whether info and results are applicable to your pt
- clinicians may look to evidence pyramid, they must understand that there may be no good evidence to support clinical judgement.
CONs:
- EBM is ‘old hat”
- it identifies statistically significant benefits that may be marginal in practice
- has made a massive amount of evidence and guidelines which are unmanageable
- the mindless application of population studies to the treatment of the individual. Plays down sound clinical judgement.
- often no RCT or gold stndrd in literature to address clinical q
What are the key steps in the process of applying EBM?
Craft a clinical question (PICO)
- Search the medical literature (medical informatics)
- Find the study that will best answer the question
- Perform a critical appraisal (check for validity and bias)
- Determine how the results will help you care for your patient
- Evaluate the results in your patient or population
What is the commonest cause of a hospital acquired s. aureus bacteraemia?
Vascular access devices (VADs)
You are asked to examine a pt who has a UTI with an ESBL-producing E.coli. What precautions do you take?
Contact precautions
