Case 1 Flashcards
(126 cards)
1
Q
What are the three main functions of the mouth?
A
Mastication, swallowing and speech.
2
Q
What are the three main stages of swallowing?
A
Oral, pharyngeal and esophageal.
3
Q
Which stage of the swallowing process in entirely voluntary?
A
The oral phase
4
Q
What is the pharyngeal swallow co-ordinated by? Where is this located?
A
It is co-ordinated by the swallowing centre on the medulla oblongata and the pons
5
Q
What are the four stages of the oral phase of swallowing?
A
Moistening, Mastication, Trough formation and movement of the bolus posteriorly.
6
Q
What are the three main pairs of salivary glands which cranial nerves innervate each?
A
Parotid (IX/Glossopharyngeal) and submandibular & sublingual (both innervated by VII/Facial)
7
Q
What are the five main stages of swallowing?
A
Anitcipatory, Oral preparatory, Oral voluntary, Pharyngeal and Oesophageal
8
Q
How man times roughly do we swallow a day?
A
1000 times a day
9
Q
What two areas of the brain are involved in salivation in the anticipatory stage?
A
The amygdala and the cortex
10
Q
In what stage does mastication occur?
A
The oral preparatory stage
11
Q
What is bypassed by drugs absorbed through the mucous membrane of the mouth?
A
The first pass metabolism in the liver
12
Q
What controls the movement of the tongue up and back against the palate in the oral voluntary stage?
A
The cortex and the medulla
13
Q
What is the last stage of swallowing that is predominantly voluntary?
A
The oral voluntary stage
14
Q
What are the five steps of the pharyngeal stage of swallowing?
A
the narrowing of the opening of the pharynx, the nasopharynx closes, the closing of the opening of the trachea, the opening of the oesophagus and the pharynx pushing food into the oesophagus
15
Q
What are pulled medially inwards in order to narrow the the opening of the pharynx?
A
The palatopharyngeal folds.
16
Q
How is the naopharynx closed?
A
The levator veli palatini contracts causing the soft palate and the uvula to rise and closes them off.
17
Q
What apart from the moving of the epiglotis prevents food from entering the trachea?
A
The pulling together of the vocal folds.
18
Q
What is the term for the interruption of breathing caused by swallowing?
A
swallowing apnea
19
Q
What part of the brain receives all of the mouth’s sensation?
A
In or near the tractus solitarius.
20
Q
What nerves supply motor innervation the pharynx
A
CN 5,9,10 and 12 and some of the superior cervical nerves.
21
Q
What is the longest stage of swallowing?
A
The oesophageal stage
22
Q
What is the nervous control of the oesophageal stage of swallowing?
A
The medulla and the enteric nervous system.
23
Q
What type of muscle are the different parts of the oesophagus composed of?
A
The top third is striated muscle the bottom two thirds smooth muscle
24
Q
What is the innervation of the different parts of the oesophagus?
A
The upper third (striated muscle) is innervated by CN 9&10 the lower two thirds (smooth muscle) is is innervated by the myenteric plexus with connection to the vagus nerve
25
What causes the sequential activation of the pharyngeal and oesophageal muscles in volved in swallowing? What neurotransmitter is used?
the vagus nerve, Ach is the neurotransmitter.
26
What distinguishes the lower oesophageal sphincter from most other sphincters?
It has no specific sphincteric muscle.
27
What is the effect of an increased level of blood gastrin on the LES? What puspose does this effect serve?
increases its muscle tone. This prevents reflux via distention as the stomach contracts.
28
Activation of what rectors innervated by what nerves help maintain the contraction/closure of the LES
Vagal Ach receptor (stimulated by the vagus nerve) and alpha adrenergic receptors (stimulated by sympathetic nerves)
29
Where is the swallowing pattern generator located?
At the medulla and base of the pons.
30
What are the two types of nerve in the swallowing pattern generator?
Generator and switching neurons
31
What is the role of the generator neurons in the swallowing pattern generator?
To trigger and time the swallowing process
32
What is the role of switching neurons in the swallowing pattern generator?
To distribute the drive to the various motor neurons involved in swallowing
33
Where are the generator neurons of the swallowing pattern generator located
the dorsal medulla
34
Where are the switching neurons of the swallowing pattern generator located?
The ventrolateral medulla
35
Via what nerves is sensory information from the oropharynx, larynx and oesophagus fed back to the swallowing center?
CN5 and 9
36
Via what nerves does the swallowing pattern generator send impulse to the muscles involved in swallowing?
CN 5, 7, 9, 10 & 12 as well as superior cervical nerves
37
What are the three types of protective receptors in the oesphagus?
Chemical, Thermal and Mechanical/stretch.
38
How apart from activating muscles that obstruct the airway does the swallowing center pause breathing?
It also inhibits neurons in the respiratory centre
39
What type of innervation is responsible for the gag reflex?
Parasympathetic nerves.
40
How might a thyroid problem cause swallowing problems?
A goitre can apply addition pressure on the area underneath it.
41
What does odynphagia mean?
Pain during swallowing
42
What is Achalasia?
When the LES does not relax enough to allow propulsion of the food into the stomach.
43
Damage to what is the most common cause of Achalasia?
The myenteric pexus.
44
Describe how the most common complication of Achalasia arise?
The tight LES does not allow the passage of food so it builds up within the oesophagus allowing pathogens to grow within the stored food leading to ulcers around it.
45
What is scleroderma?
Autoimmune attacking healthy tissues causing the stiffening of the oesophageal and pharyngeal muscles.
46
What type of bacteria is most commonly associated with aspirational pneumonia?
aerobic gram negative ( the most common are streptococcus pneumonae, haemophilus influenza and Staphlococcus aureus
47
How much water is typically used in a water swallow test what health professional usually caries it out?
150ml, a speach and language therapist.
48
In what test for swallowing is a patient made to drink a non toxic form of barium how long does it usual take?
videofluroscopy, roughly 30 minutes
49
What is one unique strength of videofluroscopy that other swallowing tests lack?
It can show aspiration
50
What modality does a manometry asses swallowing function via?
pressure
51
Where is pressure shown to be highest in a manometry?
In narrow regions
52
How is a pH monitoring device inserted to it's useful place what does it detect?
It is place through the nose into the lower oesophagus and helps detect when acid reflux has occured
53
How long is an NGT suitable for? How often must the tube be replaced?
No more than six months.
54
What condition related to swallow can botox/botulism toxin treat?
achalasia
55
How is nutrition delivered in Total parenteral nutrition (TPN)
Via an intravenous catheter.
56
What kind of epithelium are the inside of the cheek covered by?
Non-keratinised squamous epithlium.
57
What muscle makes up the floor of the mouth?
the mylohyoid.
58
What kind of endothelium is the surface of the nasopharynx made up of?
pseudostratified columnar epithelium.
59
Name the three parts of the pharynx from top to bottom?
Nasopharynx, oropharynx, Laryngopharynx
60
What are the two sets of tonsils in the oropharynx?
Lingual and palatine.
61
What are the superior inferior and lateral boundaries of the oropharynx respectively?
The base of the tongue, the hyoid bone adn the palatoglossal and glossopharyngeal arches.
62
At what level does the oesophageus pass through the mediastinum?
C6
63
At what level is the oeesophageal hiatus what does the oesophagus pass through at this point?
It is at the T10 level, it passes through the stomach.
64
What does the phrenicoesophageal ligament connect?
The oesophaguus to the border of the diaphragm
65
What are the for layers of the oesophagus from inner to outermost?
mucosa,submucosa, muscularis and tunica adventitia.
66
what makes up the mucosa of the oesophagus?
stratified squamous epithelium
67
Which of the four layers of the oesophagus is made of loose connective tissue?
submucosa
68
Which of the four layers of the oesophagus is composed of loose fibrous tissue?
The tunica adventitia
69
What component of the larynx is located at the level of the upper oesophageal sphincter?
The cricoid cartilage
70
What are the two main pexuses of the enteric nervous system?
the myenteric/Auchbach's plexus and the submucosal/meissener's plexus
71
Where is the myenteric/ auchbach's plexus located? What is its role?
Between the the logitudinal and circular muscle layers. It controls gut motility.
72
Where is the submucosal/Meissener's plexus located? What is it's role?
It lies in the submucosa and controls gastrointestinal secretion and local blood flow.
73
Which branch of the nervous system delivers the majority of the input for oesophageal peristalsis and sphincter control?
autonomic nervous system.
74
What is the name for the nerve bundles/strands that connect the ganglia within the submuscosa of the oesophagus?
interganglionic fascicles.
75
What forms the borders of the mouth?
The cheeks, hard and soft palates and the tongue.
76
What muscle lies within the cheeks?
The Buccinator muscles
77
What is the name for the midline fold of mucous membrane that attaches each lip to the gums?
The labial frenulum
78
What are the two portions of the mouth?
The vestibule and the oral cavity proper.
79
What are the borders of the oral cavity proper?
From the gums and teeth to the faucial isthmus (The opening between the oral cavity and the oropharynx)
80
Which parts of the palate are made up of the soft and hard palate?
The anterior two thirds are made up by the hard palate the posterior third is made up of the soft palate.
81
What parts of the skull make up the bone of the hard palate?
The palatine process of the maxillae and the horizontal plates of the palatine bone
82
What two folds are continuous with the soft palate?
The palatoglossal and palatopharyngeal arches
83
What three muscles are responsible for the elevation of the pharynx and larynx during swallowing and speaking?
The stylopharyngeus, salpingopharyngeus and palatopharyngeus.
84
What type of epithelium lines the laryngopharynx?
non-keratinised stratified squamous epithelium.
85
What are the roles of the internal and external layers of muscle in the laryngopharynx respectively?
To elevate the pharynx and larynx during swallowing and speaking. To constrict the walls of the pharynx during swallowing.
86
Where does the oesophagus pass through the diaphragm? What vertebral level is it at?
It passes through the oesophageal hiatus at T10
87
How much of the oesophagus extends pass the diaphragm what does it join at the end?
it extends 2 cm past the diaphragm and joins with the cardiac orifice of the stomach at the end.
88
Which layers of the oesophagus are responsible for the "star shaped" appearance of the opening in the cross section?
The Mucosal and Submucosal layers.
89
What branch of the nervous system controls oesophageal peristalsis and sphincter control? Which branches also contribute
Autonomic nervous system. The parasympathetic, sympathetic and enteric nervous systems also contribute.
90
What type of muscle is the upper oesophageal sphincter made of, what is it's nervous control?
It is made up of striated muscle and is under somatic (cholinergic) control of vagal motor neurons in the nucleus ambiguus.
91
Efferents from which nerve modulate oesophageal peristalsis, which type of nerve is responsible for excitation and inhibition respectively?
efferents from the vagus nerve modulate peristalsis. Parasympathetic cholinergic and sympathetic NO mediated neurons are responsible for excitation and inhibition respectively.
92
The LES is innervated by both sympathetic and parasympathetic nerves, which nerves are each branch primarily from?
The parasympathetic is mostly vagus, the sympathetic is primarily splanchnic
93
What is the nickname for the parasympathetic nervous system?
The rest and digest nervous system.
94
What is the nickname for the sympathetic nervous system?
The fight or flight nervous system.
95
motor innervation to the upper oesophageal sphincter is controlled by which branch of the nervous system?
the somatic nervous system.
96
Where are the cell bodies of the motor neurons located what nerve do they travel via?
They are located in the rostral nucleus ambiguus/retrofacialis nucleus and travel predominantly through the vagus nerve.
97
What branch of the nervous system provides the majority of the extrinsic motor innervation to the smooth muscle portion of the oesophagus where do these nerves originate from?
Parasympathetic nerves originating from the dorsal motor nucleus of vagus.
98
Where is the myenteric/Auerbach's plexus located?
In between the longitudinal and circular muscle layers of the oesophagus, stomach and intestine
99
What types of nervoustissue are the mesenteric/Auerbach's and the submucosal/Meissener's plexus composed of?
ganglia connercted by nerve bundles/strands called interganglionic fascicles.
100
What are three factors that can cause depolarization in oesophageal plexuses?
Stretching of the muscle, parasympathetic stimulation and certain gastrointestinal hormones.
101
What is the resting membrane potential of the oesophageal plexuses on average?
-56 millivolts
102
Name two excitatory/contracting agents of the oesophagus
substance P and acetylcholine
103
Name four oesophageal relaxation/inhibitory agents
vasoactive intestinal peptide, calcitonin related peptide, pituitary adenylate cyclase activating peptide and NO synthase
104
Which muscle is known as the lead muscle of the swallowing reflex?
The mylohyoid
105
Which part of the oesophagus has the highest resting tone?
The lower oesophageal sphincter (LES)
106
What NS branch and nerve are though to be responsible for the excitatory ganglionic stimulation that contributes to the LES' high resting tone?
Parasympathetic stimulation from the vagus nerve.
107
What is the resting membrane potential of the LES?
-66mV
108
Muscle from where help supplements the function of the LES during inspiration, cough or abdominal strain?
The muscle of the right diaphragmatic crus.
109
When does LES relaxation happen in relation to swallowing and how long for?
2 seconds after swallowing for 6-10 seconds.
110
What are the two causes of LES relaxation?
Inhibition of excitatory vagal stimulation and activation of inhibitory vagal innervation (NO is a neurotransmitter in this system)
111
What are the two types of mucous secreting glands in the oesophagus?
Mucous-secreting oesophageal glands and oesophageal cardiac glands
112
Where are mucus secreting oesophageal glands found, what type of gland are they?
They are found in the submucosa and are compound tubuloacinar glands.
113
Where are oesophageal cardiac glands found? What type of gland are they?
They are found in the lamina propria most (they are also most frequent at the terminal part of the oesophagus) and are branched tubular glands.
114
Roughly how much saliva is secreted daily?
1 liter
115
What alpha amylase is released in saliva?
Ptyalin.
116
Why is the pH of saliva kept at roughly at 6-7?
As this is a favorable range for the action of ptyalin (an alpha amylase)
117
What type of secretion do the parotid glands release?
almost entirely serous.
118
How much of salivary volume do the submandibular glands release?
70%
119
What are the three principle salivary glands?
parotid, submandibular and sublingual glands.
120
What causes Cl ions to be reabsorbed from salivary ducts passively?
Na ions are reabsorbed while secreting K ions however more Na is absorbed than K is released so a -70mV electrochemical gradient
121
What is then difference between high flow and low flow rate saliva?
Low flow rate saliva is hypotonic the faster the flow rate the closer to isotonic it becomes.
122
Where does the parasympathetic innervation of the salivary glands originate from? What effect does it have on saliva secretion?
It originates from the superior and inferior salivary nuclei via CN 7&9 (facial and glossopharyngeal) and increases the rate watery of salivary secretion.
123
What receptor is parasympathetic stimulation of the salivary glands mediated by what nerves is it applied via what effect does this have on saliva secretion?
It is mediated by alpha adrenergic receptions via T1-T3 of the superior cervical ganglion. It increases the rate of viscous saliva secretion..
124
What are the four main aerobic bacteria implicated in aspirational pneumonia?
Steptococcus pneumoniae, staphylococcus aureus, haemophilus influenzae, pseudomonas aeruginosa.
125
What type of bacteria is most commonly associated with aspirational pneumonia?
aerobic.
126
As well as aerobic pathogens, bacteria originating from where can also be implicated in aspirational pneumonia?
anaerobic oral flora
