Antomy Flashcards
what constitutes the upper respiratory tract?
- nasal cavities
- oral cavity (mandible and hyoid bone, epiglottis)
- pharynx
- larynx (vocal cords)
what constitutes the lower respiratory tract?
- trachea
- right and left bronchi (bifurcation)
- lobar bronchi 9one for each lobe)
- segmental bronchi (one for each of the 10 bronchopulmonary segments)
- bronchioles
- alveoli
what happens at the C6 vertebra?
1 - the larynx becomes the trachea
2 - the pharynx becomes the oesophagus
what are the lobes of the lungs?
left - upper and lower lobes
right - upper, middle and lower lobes.
what separates the lobes of the lungs?
fissures (deep crevices)
what does each lung lobe and bronchopulmonary segment have?
- air supply, blood supply, lymphatic drainage and nerve supply.
Describe the inside of the bronchial tree.
- respiratory epithelium
- mucous glands secrete onto the epithelial surface
- cilia sweep the mucous superiorly towards the pharynx (mucociliary escalator)
what interferes with the beating of the cilia?
- toxins in cigarette smoke
- cooling/drying of mucous
Describe hyaline cartilage in the respiratory tree.
- hyaline cartilage supports the walls of the trachea and bronchi
- it assists with the patency of the airways (holding them open)
- the amount of cartilage gradually decreases distally
- the walls of the most distal bronchioles and of alveoli do not contain any cartilage
Describe smooth muscle in the walls of the airways.
- becomes progressively more prominent distally
- most prominent feature of the bronchioles walls (allowing them to constrict and dilate)
- not found in alveoli
what are the main requirements of gas exchange?
- sufficient functioning lung tissue
- sufficient 02 in the air we breathe in
- no C02 in the air we breathe in
- minimal thickness of the walls of the alveoli to facilitate gaseous diffusion
- minimal tissue fluid in the tissue spaces around the alveolar capillaries to facilitate gaseous diffusion
what are the main problems to the respiratory tract?
- the tract becomes narrowed due to; - the bronchioles constricting (asthma), swelling of the mucosa and overproduction of mucous (asthma) or a growing tumour externally compressing the tract.
- foreign bodies being inhaled to partially or fully stop breathing.
Describe the nasal septum.
- bony part of the nasal septum - ethmoid bone (superiorly) and vomer (inferiorly)
- cartilaginous part
Describe the nasal cavity.
- relatively featureless medial wall
- interestingly featured lateral wall
- a floor (formed of palate)
- a roof (formed by the midline part of the floor f the anterior cranial fossa)
what does the larynx consist of?
- epiglottis
- thyroid cartilage
- cricoid cartilage
- 2 arytenoid cartilages (posteriorly)
what is the function of the larynx?
- cartilage helps maintain patency pf the upper respiratory tract
- helps to prevent entry of foreign bodies into lower respiratory tract
- produces sound
where do large foreign bodies tend to block the URT?
- Rima glottidis (narrowest part of larynx)
what do vocal ligaments do?
- airway protection and cough reflex
- phonation (producing sound)
- articulation (producing speech)
what does the Heimlich manoeuvre aim to do?
raise abdominal pressure > forces diaphragm superiorly > raises pressure in chest > raises pressure in lungs > forces air into trachea > air forced through rima glottidis to expel the foreign body.
how do the we warm, humidify and clean the air we breathe in?
- the conchae (superior, middle and inferior) greatly increase the surface area of the lateral walls of the nasal cavities
- the conchae produce turbulent flow bringing the air into contact with the walls
- the respiratory mucosa lining the walls of the nasal cavities has a very good arterial blood supply providing warmth
- the respiratory mucosa produces mucous providing moisture
- the “sticky” mucous traps potentially infected particles
- the cilia of the mucosa waft the mucous to the pharynx to be swallowed (into gastric acid)
- tonsils produce white blood cells in defence against infection
what are the parts of the pharynx?
- nasopharynx
- oropharynx
- laryngopharynx
Describe the thoracic skeleton.
12 pairs of ribs; 1-7 = true ribs (attach via costal cartilage to the sternum), 8-10 =false ribs (attach above to the sternum), floating ribs = 11 and 12 ( no attachment to sternum)
- intercostal space, costal margin, clavicle and scapula
- sternum = manubrium, body, xiphoid, sternal angle
Describe the joints and bones of the thoracic skeleton.
see diagram.
what are the muscles of breathing?
- external intercostal muscle, internal intercostal muscle and innermost intercostal muscle.
- layers attach between adjacent ribs making the chest wall expand.
- diaphragm also important.
where is the pleural cavity?
between the parietal and visceral layers of pleura.
- surround the lungs in 3D apart from where the main bronchus enters
what is acinus?
- the functional unit of the lung
- extends through the respiratory bronchiole, alveolar ducts and alveoli
what are the classification of lung tumours?
- 4 common; -adenocarcinoma, squamous carcinoma, small cell carcinoma, large cell carcinoma
- neuroendocrine tumours
- bronchial gland tumour
what classification of lung cancer are non-smokers likely to get?
- adenocarcinoma
why is it so important to classify cancers?
- prognosis
- treatment
- pathogenesis/biology
- epidemiology
which lung cancer types have the worst survival time?
small cell (then large cell, squamous cell and then adenocarcinoma)
what is the anatomy of the pleura?
- serous membranes
- the visceral pleura covers the lungs and forms interlobar fissures.
- the parietal pleura covers the mediastinum, diaphragm, and inner surface of the thorax
- inferior margins of the pleura considerably lower than the corresponding border of the lung.
- the two layers combine around the hila of the lung - so it has no pleural coverage
- the pleural layers combine to form the pulmonary ligament =, which runs inferiorly and attaches the root of the lung to the diaphragm.
how does the pleural anatomy allow it to perform its function?
- lubricates the 2 pleural surfaces
- allowing the pleura to slide smoothly during respiration
- surface tension allows lung surface to stay touching thoracic wall, creating a seal between the 2 surfaces.
what is the isthmus of the thyroid?
- bride of thyroid tissues connecting left and right
- above jugular notch and anterior to tracheal cartilages 2-4
What is the mediastinum?
the cavity between right and left pleural cavities
-contains heart
Describe the lungs/ lung development in an embryo.
-chest cavity initially contains pleural cavity and no lungs
-lung develops pushing pleural cavity and eventually the visceral and parietal pleura come into contact (with fluid in between)
partietal = in contact with body wall
visceral = in contact with lungs
what are the fissures of the lungs?
on the right - oblique and horizontal
on the left - only oblique
where in the intercostal spaces is the nerve supply?
-anterior ramus of spinal nerve (intercostal nerve)
what artery and vein supplies/ drains the posterior part of the intercostals?
artery = thoracic aorta
vein = azygous vein
(meets anterior parts)
what artery and vein supply the anterior parts of the intercostals?
internal thoracic artery and veins
meets posterior parts
where are the main and collateral neurovascular bundles found supplying the lungs?
main = just below rib collateral = just above rib
what is the diaphragm?
- internal part of the body wall
- right dome usually more superior
- muscular part attaches to; the sternum, the lower 6 ribs and costal cartilages, L1-L3 vertebral bodies
how is the diaphragm supplied?
-muscular part supplied by right and left phrenic nerve at the C3,4 and 5 anterior rami
where are phrenic nerves found?
- found in neck on anterior surface of scalenus anterior muscle (anterior to root of lung)
- in chest descending over lateral aspects of the heart (pericardial sac)
- supplies somatic sensory and sympathetic axons to the diaphragm and fibrous pericardium
- supplies somatic motor axons to the diaphragm.
how is the surface anatomy of the female breast labelled?
- split into 4 quadrants
- superolateral
- superomedial
- inferolateral
- inferomedial
- axillary tail
- areola (nipple)
what artery and vein supplies the breast?
(from subclavian) internal thoracic artery
how are breasts lymphatically drained?
- upper and lower lateral quadrants drain to axillary lymph nodes (unilateral)
- upper and lower medial quadrants drain into parasternal lymph nodes (bilateral)
Describe the surface anatomy of the chest.
- jugular notch
- manubrium
- clavicles
- trachea
- sternum
- sternal angle
- xiphoid process
- costal margin
Describe the features of the anterolateral chest wall.
- superficial fascia =adipose tissue, insulation
- deep fascia = fibrous, thin, strong, protective
- sensory nerves = intercostal nerves
- muscles = deltoid and pectoralis major
- cephalic vein = in delto-pectoral groove
- long thoracic nerve supplies serratus anterior (on side)
what does the serratus anterior do?
-anchors scapula to ribs
supplies by long thoracic nerve
what are the parts of the parietal pleura?
- cervical
- costal
- diaphragmatic
- mediastinal
what is the significance of the costodiaphragmatic recess?
- most dependant part of pleural cavity (most inferior)
- located between diaphragmatic partietal pleura and costal parietal pleura
- costophrenic angle is the very most inferior region
- abnormal fluid in the pleural cavity will drain into here
what are the structures of the root of the lungs?
- main bronchus
- pulmonary artery
- 2 pulmonary veins
- lymphatics
- visceral afferents (sensory)
- sympathetic nerves
- parasympathetic nerves
what is the hilum?
where the main bronchi enter the lungs
what are the surface marking of the hilum?
- main bronchi attachment (posterior)
- pulmonary arteries
- pulmonary veins (most anterior)
- Pulmonary lymph nodes
what is the rough overview of what happens when coughing?
- sensory receptors in the mucosa of oropharynx, laryngopharynx, larynx and respiratory tree are stimulated
- CNS causes a deep inspiration using accessory muscles
- adduction of vocal cords to close the rima glottidis
- contraction of abdominal wall muscles to build up pressure pushing the diaphragm up and increases lung pressure
- vocal cords suddenly abduct to open rima glottidis
- soft palate tenses and elevates to stop sneezing
what spinal nerves are stimulated in sneezing?
- CN 5 and 9
what spinal nerves are stimulated in coughing?
-CN 9 and 10
what are the carotid sheaths?
- protective tubes of cervical deep fascia
- attach superiorly to bones of the base of the skull
- blends inferiorly with the fascia of the mediastinum
- contains; vagus nerve, internal carotid artery, common carotid artery and internal jugular vein
how do motor axons travel to the lungs?
-they travel from the tracheal bifurication along the branches of the respiratory tree to supply all mucous glands and all bronchiolar smooth muscles
how do pulmonary visceral afferents travel ?
-travel from visceral pleura and respiratory tree to the plexus and then follow the vagus nerve to the medulla of the brainstem
what are the intercostal nerves?
-anterior rami of the spinal nerves T1-11
what happens to the pectoralis major and minor when the upper limb position is fixed?
- the parts which are normally fixed move and allow a muscles o pull the ribs upwards and outwards to increase inhalation
what allows the vocal cords to move ?
the arretanoid cartilage
how are laryngeal muscles supplied?
-somatic motor nerves branching off the vagus nerve (CN10)
what does the vagus nerve do?
- mixed cranial nerves
- connects CNS at the medulla, descends through neck within the carotid sheath
- supplies somatic sensory and motor axons to larynx
- descends posterior to lung root and supplies parasympathetic axons to the chest organs
- pass through diaphragm on the oesophagus
- divides at stomach for foregut and midgut organs
what are the layers of abdominal wall muscles?
(left and right)
- external oblique
- internal oblique
- transversus abdominal
- rectus abdominis (6 pack)
Describe external oblique muscles
- joined to the superficial aspects of the lower ribs and to the anterior part of the iliac crest and pubic tubicle
- fibre direction the same as the external intercostal muscle at the sides
- aponeurosis (flattened tendon) in the middle
- the linea semilunaris = where the muscle fibres end and the aponeurosis begins
Describe the internal oblique muscle.
- fibre in the same direction as internal intercostal muscle
- aponeurosis (flattened tendon) of the right internal oblique blends with aponeurosis of the left internal oblique at the midline linea alba
- attaches superiorly to border of lower ribs and inferiorly to the iliac crest and thoracolumbar fascia of the lower back
Describe the transverse abdominus muscle.
- right and left aponeurosis blend
- attaches superiorly to deep aspects of lower ribs and inferiorly to iliac crest and throacolumbar fascia of the lower back
what are the functions of the abdominal muscles?
- tonci contractions to maintain posture and support the vertebral column
- contractions produce movements of the vertebral column (flexion, lateral flexion, rotation)
- guarding contractions protect the abdominal viscera
- contractions increase the intra-abdominal pressure to assist defecation, urination and labour
- contractions aid forced expiration
what are the parts of the mediastinum?
- superior
- anterior
- middle
- posterior
what are the consequences of mediastinal shift?
- tracheal deviation
- superior vena cava compression lead to reduced venous return to the heart leading to hypotension
