Paramedic Resource Manual Flashcards
What is apart of the upper respiratory tract (4)?
- nasal cavity/sinuses
- pharynx
- larynx
- trachea
What is apart of the lower respiratory tract (9)?
- right and left mainstem bronchi
- secondary bronchi
- tertiary bronchi
- bronchioles
- terminal bronchioles
- respiratory bronchioles
- alveolar ducts
- alveolar sacs
- alveoli
What composes the nasal cavity?
- has a septum dividing the anterior nares
- has posterior nares which open to nasopharynx
- each nasal cavity has inferior, middle and superior turbinates
What is the purpose of the turbinates?
- increase surface area
- warming air
- moisture content
What area do nosebleeds impact?
- anterior nasal septum in young people
- posterior nasal structures in elderly
where is woodruff’s plexus?
over middle turbinate - if damaged bleeding will persist (need surgery to fix)
What separates the nasal cavity from the brain? What happens if fracture occurs here?
Cribiform plate
- fracture can lead to CSF fluid leak
What bones make the roof of the nasal cavity?
ethmoid and sphenoid bones
What makes up the hard palate?
palatine and maxillary bones
What are the 4 sinuses?
- frontal
- maxillary
- ethmoid
- sphenoid
Where does the pharynx sit?
base of skull - 6th vertebrae
(nasopharynx, oropharynx, laryngopharynx)
Nasopharynx
- directly behind nose
- air passage only
- when you swallow, soft palate and uvula move up to prevent food from entering nasal cavity
Oropharynx
- posterior to oral cavity
- composed of soft palate, uvula, tonsils
Laryngopharynx
- food and air passage
- runs to larynx where it then separates into your food and air flow
- cricoid cartilage is inferior, esophagus is posterior
What is the Eustachian tube? Where is it located?
Duct going from middle ear - nasopharynx
- allows for pressure control in the ear
- normally closed, opens during things like swallowing, yawning, chewing
Where does the larynx sit?
from hyoid bone to cricoid cartilage in trachea
4 cartilages of the larynx
- thyroid
- cricoid
- arytenoids
- epiglottis
What commonly happens at the larynx level?
airway obstruction - often due to FBO - crich occurs here
What bone is found in larynx?
hyoid bone - directly under the chin which goes to thyroid (adam’s apple)
What is the purpose of thyroid cartilage?
- attachment point
- protects vocal cords
Epiglottis
- behind hyoid cartilage
- during swallowing it covers larynx to prevent food from going down the wrong tube
- swelling at this site can lead to airway obstruction
Vocal cords
go from thyroid to arytenoid cartilages
- can open/close
- controlled by muscles controlled by laryngeal nerves
Where does the trachea sit? What is it made of?
Goes from the cricoid cartilage to the fifth thoracic vertebrae
- 10cm long
- made of incomplete cartilage rings which allow for flexibility to keep airway open
- un-closed part faces esophagus which allows for food to pass
What are accessory parts to the lower respiratory tract?
- pleura
- pleural cavity
- muscles of respiration
The bronchi
- being where trachea ends - divides into left/right mainstem passing through the hilum
- made of cartilage rings like trachea but as it progresses it goes to smooth muscle
- as they go through the lungs they turn to secondary bronchi and than tertiary, going to smaller units until they form bronchial trees (where the bronchioles form)
Difference between right and left main bronchi stem?
Right = shorter, more vertical/ in line with trachea
- often times tube placement goes into this bronchi, or FBO will go here
Respiratory bronchioles
branches of the terminal bronchioles that subdivide into several alveolar ducts
Alveoli
- contained in alveolar sacs (coming off the ducts)
- has respiratory membrane separating capillary blood from the air in alveoli (this is the membrane in which gas exchange occurs)
- things that thicken this membrane lead to less gas exchange (CHF, pneumonia)
Lung anatomy
- takes up most of the thorax, surrounded by pleura sac
- bases end above diaphragm, apex is above collar bone
- each lung has a hilum where things enter/leave lungs
- left lung (2 lobes, oblique fissure divides)
- right lung (3 lobes, has horizontal and oblique fissure)
Pleural cavity
- contains the lungs
- has visceral and parietal layers which have serous fluid between (reduces friction)
The thorax
- chest cavity
- have right/left pleura cavities and mediastinum
- mediastinum contains heart, esophagus, sternum, trachea
- pleural cavity contains lungs
What is atelectasis?
Lung collapse
- can be from cavity compression (fluid, air, diseases) or could be from decreased surfactant
How does air flow? How does that work with us to have inspiration?
- air flows from high to low pressure
- during inspiration, our thoracic cage expands, leading to less overall pressure inside the lungs/cavity (this will now make atmospheric air higher pressure, letting air flow into the alveoli)
How does the diaphragm move during inspiration/expiration?
i - contracts and moves downward
e - relaxes/moves up, sternum moves inward
What are the muscles of inspiration?
diaphragm and external intercostal muscles
How do the intercostal muscles assist respiration?
move ribs upwards/out (increase thoracic cage) as well as contraction of these muscles keep intercostal spaces from being sucked in during inspiration
What can lead to diaphragm paralysis?
transection of spinal cord above C3
What are the muscles of expiration?
internal intercostals and abdominal muscles
Does expiration use energy?
- passive process mostly unless diseases present
- when inspiration occurs, the lung tissue stretch causing potential energy to be stored in them - expiration will occur due to recoil in the lungs
How do abdominal muscles work during expiration?
Contraction moves diaphragm upwards (when it relaxes) and it depresses the ribs leading to less thoracic cage volume
What is pulmonary compliance?
- healthy lungs need to be able to expand (elastic tissue)
- compliance is the amount of pressure needed to expand the lungs
- the more pressure needed to expand them = less complaint
- diseased lungs usually have higher compliance
What is elastance?
ability for lungs to return to normal after they stretch (how well they recoil)
What % of oxygen do we use to breathe?
- respiratory muscles need less than 5% of our oxygen to function
- in patients with respiratory disorder, there system uses around 25% of total oxygen consumption
What structure is more anterior the larynx or the esophagus?
the larynx
What causes the wheezing in asthma?
airway constriction
Why do very sick asthmatic patients often have very little wheezing?
the production of sound is dependent upon adequate ventilation
- decreased ventilation, movement of air results in decreased wheezing
- decreased movement of air results from bronchoconstriction, mucosal edema and increased mucous production which causes obstruction of flow
What are the 3 pathologies involved in COPD?
- asthma
- bronchitis
- emphysema
What is tidal volume?
- the amount of air inhaled and exhaled during a normal breathing cycle at rest
- 400-500ml in healthy adult is normal
What is residual volume?
amount of air remaining in lungs after expiration
Total lung capacity
total amount of air lungs can hold
What controls our bodies ventilation?
- centers in the brainstem
- responds to increasing levels of CO2 (causes us to increase respiratory rate, while it decreases our respiratory rate when CO2 levels are below normal) - hypercapnic drive
How is ventilation controlled in someone with COPD?
- they use thier hypoxic drive
- bases respirations on oxygen levels, not CO2
- due to normally high CO2 levels making them have hypercapnia - body will shift to using oxygen levels as they don’t blow off CO2 normally
Ventilation vs. Perfusion
V = amount of air moving into and out of system
P = flow of blood through tissues
ideally you want V=Q
When does pulmonary shunting occur?
anytime that blood flows through the lungs and does not pick up enough oxygen
What is dead space?
Air going in and out is equal (no gas exchange)
- it is ventilation without perfusion (high V/Q ratio)
What is a shunt?
Perfusion without ventilation (low V/Q)
- when oxygen can not enter, CO2 can not exit (COPD)
- even though area is perfused, not ventilated which leads to shunting of blood to other areas which can be ventilated
Asthma - what is it?
- chronic inflammatory disease of airways
- widespread narrowing of airways - due to smooth muscle contraction, and as it goes on also can be from mucosal edema/mucus production
Symptoms of asthma
wheezing, coughing, SOB, anxiety. tachycardia, nasal flaring, accessory muscle use
- as it goes on and compensation declines, may see confusion, diminished/absent wheezing, become obtunded
Why do lungs become overinflated in COPD/asthma?
air trapping = overinflated
Signs someone is hypoxic? When can it occur?
Combative, confusion, aggressive, visual problems, seizures
- when PAO2 falls below 60 (normal is 80-100)
Hypercapnia
Excessive carbon dioxide in the blood (ventilation not sufficient enough to remove it)
- COPD, overdoses where respiratory drive is declined
What does partial pressure mean?
The pressure of gas in a mixture if it were acting alone
How does diffusion of oxygen work? (blood to tissues)
- in venous blood, PAO2 is 40mmHg
- as blood enters capillaries it comes into contact with alveolar air which is 100mmHg (remember air goes from high to low) so oxygen will diffuse into venous and diffuse until it is equalized (this blood now goes to the heart and into the systemic circulation)
- in tissues the PAO2 is 40mmHg. Once this oxygenated blood reaches tissues (it is now 100) - it will diffuse into the tissues
What 2 factors impact oxygen transportation to the tissues?
- perfusion
- concentration of hemoglobin/it’s affinity for oxygen
Structure of hemoglobin
It is a four sub unit protein containing iron - has 4 irons which can attach to an oxygen (becomes oxyhemoglobin)
What is the oxygen disassociation curve?
The graph of the relationship between the saturation of hemoglobin with oxygen and the partial pressure of oxygen
What 3 factors impact hemoglobins affinity for oxygen?
- pH
- temp
- PCO2
What will cause a downward shift to the right on the curve?
Lowering of pH (increase in H ions), increase in temp
- any shift down/to the right lowers affinity, meaning that oxygen will not bind as easily due to being in acidic state but oxygen will be more readily available for tissues
What will cause a shift upward/to the left?
Increase in pH, decrease in temp
- oxygen can bind more easily (in alkaline state) but does not give up as easy as now hemoglobin has increased affinity for oxygen
How is carbon dioxide transported?
By blood until it can be excreted by kidneys or lungs
- carried in form of bicarbonate (mostly)
- combines with hemoglobin
- dissolves in plasma
What is the BOHR effect?
- when we exhale, it shifts us towards alkaline side (blowing off CO2)
- when we are alkaline, hemoglobin has a greater affinity for oxygen
- when blood reaches tissue level, CO2 will diffuse into blood shifting the scale to be more acidic (which will decrease affinity) making oxygen more available to the tissues
Pons - how does it control breathing?
Pneumotaxic centre - switches inspiration off
Apneustic centre - switches it on
Chemoreceptors
- help to detect changes in CO2 and O2 levels
- helps control breathing
- peripheral chemoreceptors: detect CO2 changes
- central chemoreceptors: detect changes in arterial CO2 and O2
What does pulse oximetry measure? End tidal?
P = amount of oxygen bound to hemoglobin (normal = 92-96%, COPD = 88-92%)
E = amount of exhaled carbon dioxide
3
Non-rebreather mask
- 10-15pm
- uses bodies own reservoir, and the one attached to mask providing 80-95% oxygen
Aerosol mask
- for drug administration
- 5-6lpm
- 40% oxygen given
BVM
- without a bag, 60% oxygen given, with one is 100%
- for patients not ventilating at all or enough
- 15lpm
How much oxygen in D tank, M tank?
D = 350ml
M = 3000ml
Simple face mask
- similar to NRB, no bag
- 8-10 lpm
- 40-60% oxygen
Cardiogenic shock is an example of which hypoxia?
tissue hypoxia due to a lack of perfusion
3 compensatory mechanisms during shock
- neurogenic
- chemical
- hormonal
Neurogenic Compensation
- fight/flight responses
- increase hr (to increase CO), and arterial/venous constriction (trying to maintain pressure)
Chemical compensation
- decreased cardiac output and increased extrication by tissues
- chemoreceptors will stimulate respiratory centres due to this which will lead to respiratory alkalosis
Hormonal compensation
- adrenal medulla releases hormones (epi/norepi)
- due to decreased blood flow to the kidneys, RAAS will be activated
Active transport
Passage of molecules/ions against a concentration gradient (needs energy)
- usually needs carrier, ATP is energy source
- goes from low to high concentration (if needing to keep certain ions on certain sides of membrane)
Diffusion
Molecules moving from high to low (no energy needed)
- tries to maintain equal concentrations on either side of a membrane
Edema
interstitial spaces have excess of fluid
Osmosis
- passage of water across membrane from a more dilute concentration to a higher one (passive)
- will continue movement until equal amount of solutes on both sides
Passive transport
movement of molecules/ions in direction of gradient (no energy)
Solute vs. solvent
Solute - what is being dissolved
Solvent - liquid in which something is dissolved in
ICF vs. ECF
ICF = fluid within cells
ECF = fluid outside of cells
What is osmotic pressure?
Amount of pressure needed to stop osmosis (water movement)
- the more concentration on one side of the membrane there is, the more pull for water there is, meaning there is a higher osmotic pressure
Kidneys role in fluid movement
- regulation of fluid/electrolytes
- when ECF is low, kidneys will retain water, when high they will excrete more
- ADH/aldosterone play role in fluid retention
Volume depletion causes/signs
C - inability to intake (illness, dysphagia), fluid loss (diabetes, burns, kidney failure, GI issues)
S - decreased BP, increased HR, thirsty, dry skin, turgor, sunken eyes/fontanelles, altered LOA
What is a type of vital signs that hints towards volume depletion?
orthostatic vitals - when laying down patients vitals are higher, when you sit them up they drop
Volume overload
- edema often seen in lower limbs (puffy/swelling)
- due to fluid build-up in extracellular spaces
- kidney disease, CHF, anti-diuretics
What is acidosis? alkalosis?
Acidosis - pH lower than 7.35
Alkalosis - pH greater than 7.45
What is a buffer?
Substance which reacts with, and resists changes to pH - helps remove excess H+ ions to balance pH
Fixed acid
acid which is not volatile, must be excreted - can not be removed by the lungs
Hyperventilation vs. Hypoventilation
Hyper - loss of CO2 from body (blowing it off)
Hypo - retention of CO2 (decreased breathing)
Metabolic acidosis
decrease in bicarb which lowers blood pH
Metabolic alkalosis
increase in bicarb, raises pH
Respiratory acidosis
decrease in blood pH due to CO2 retention (hypoventilation)
Respiratory alkalosis
Increase in blood pH due to blowing off CO2 (hyperventilation)
What is the best response for the body to fix pH?
through the lungs, kidneys is a slower process
What is the major buffer system?
carbonic acid/bicarbonate buffer system
How does carbonic buffer work?
- CO2 at end of cellular metabolism diffuses out of the tissues into the blood where it forms carbonic acid
- carbonic acid is taken to lungs to be blown off by being reformed into water and CO2 (water will go into body)
- rapid but not effective once pH starts to return to normal
How does the bicarbonate buffer work?
- kidney tubules will adjust to reabsorb or excrete H+ ions and bicarb
- if body pH low - will excrete H+ ions and retain bicarb
- if body pH high - will absorb H+ ions and excrete bicarb
Causes of acidosis
- kidney failure
- respiratory diseases
- diabetes
- GI issues
Causes of alkalosis
- excessive vomiting
- too many antacids
(alkali overconsumption)
Nervous system function
- activates/controls body systems
- gets info regarding change and creates response
What is cerebrum composed of?
both hemispheres connected by corpus callosum
Right hemisphere vs. Left
Right side - creativity, art
Left side - logic, math, sciences
Cerebral cortex/medulla
C - grey matter (nervous tissues, cell bodies), surface has grooves called gyri and is divided into lobes by sulci (spaces)
M - white matter (myelinated axons)
Frontal lobe
- thought processing
- decision making
- muscle control
Temporal lobe
- hearing
- language
Parietal lobe
sensory area - integrates/processes sensory info
Occipital lobe
sight
Thalamus
- gets sensory info from lower body centres, sends to cortex
- sleep/wake cycles, alertness
Hypothalamus
- thirst/hunger
- body temp, sex appetite, respiration
- main link between nervous system and endocrine system
Cerebellum
- helps posture, fine motor control
- injury could lead to headache, vomiting, visual issues
The brainstem
made of medulla, pons, midbrain
Medulla
- connects cerebrum to spinal cord/lower body centres
- visual/auditory reflexes (hiccuping/coughing)
- respiratory control centre, controls HR
What is reticular formation? Where is it?
- gets info from higher centres in brain and relays it to thalamus - found in midbrain
- deals with sleep, arousal
What is the substantia nigra?
Found in midbrain, helps smooth your body movements
- damaged in Parkinson’s
Pons
- network between brain and spinal cord
- deals with sleep, respiration, eye movement, swallowing
What are the ventricles of the brain?
- four fluid filled cavities filled with CSF fluid
- CSF produce is for cushion, protection for the brain/spinal cord
Meninges
- composed of dura, arachnoid and pia mater (outer to inner)
- covering of the brain/spinal cord
- can become infected: meningitis
Dura mater
- thick
- outer most layer of the meninges surrounding and protecting the brain and spinal cord
Arachnoid mater
- thin
- delicate membrane that adheres to inner part of dura
- has subarachnoid space under it where CSF is found
Pia mater
transparent membrane that adheres to brain surface or the outside of spinal cord
- has blood vessels
What are the 4 plexuses of the body?
Sacral - serves pelvis, buttocks, thighs, feet
Lumbar - serves back, abdomen, groin, thighs
Brachical - serves chest, shoulders, arms, hands
Cervical - serves head/neck/shoulders
What will cause brain cell death?
- brain death occurs after only a few minutes of no oxygen, it can only store 10 seconds worth of oxygen
- if diminished glucose, less cellular metabolism which leads to cell death
What drains blood from the brain?
internal jugular vein
The spinal cord
communication pathway between brain and body - terminates at L1
How many spinal nerves are there?
31 pairs
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal
Sensory/motor roots of spinal cord
- at dorsal aspect, sensory roots which bring sensory info to spinal cord from muscle
- at ventral aspect, motor roots which bring info from spinal cord to skeletal muscle
Functional unit of nervous system
neuron
3 kinds of neurons
motor - carry info from brain/spinal cord to muscles
sensory - carry info from receptors to brain/spinal cord
interneurons - within brain/spinal cord allowing for communication between the two
Cerebrovascular diseases
- due to lack of blood flow to the brain
- due to thrombosis, embolism or hemorrhage
3 main kinds of head fractures
- simple
- depressed
- basilar
Simple head fracture
lines or cracks in skull, no displacement - linear
Depressed head fracture
indent into the skull - often in frontal or parietal regions
- high energy trauma, may lead to brain tissue damage
Basilar head fracture
Involves skull of base, often extension of linear
- racoon eyes and battle signs are common signs seen later on
- may leak CSF from ears
Early signs of herniation
- headache
- vomiting
- altered
- cushing’s triad
- pupils increased
- decerebrate or decorticate posturing
Somatic vs. Autonomic reflexes
S - contraction of skeletal muscle
A - contraction of smooth/cardiac muscle
What happens if C3-4 is damaged?
paralysis of diaphragm (where phrenic nerve is)
What are the most common spine injuries?
cervical and lumbar spine
If you damage T10-L2
can lead to abdominal injuries - can be severe
Paraplegia vs. Quad
P - loss of CSM to legs (damage to T12-L1)
Q - loss of CSM to all limbs (C5-6 damage)
If L4-5 is damaged
loss of CSM to legs
Compound head fracture
brain tissue exposure potential (open)
What is abdominal pain usually from?
- organ distention
- ischemia (occlusion)
- inflammation
Visceral, somatic and referred pain
V - distention of organs, dull/not localized, cramping with N/V, sweating
S - due to peritoneum nerve irritation or from abdominal wall - sharp stabbing pain, localized
R - pain felt in areas other than at the source
Liver
Exocrine and endocrine gland
- stores glycogen, makes bile in RUQ
Spleen
- helps prevent infection, activates immune system
- in LUQ, highly vascular
- may have Kehr’s sign if damaged - pain to tip of left shoulder
Pancreas
Endocrine and exocrine gland
- makes digestive enzymes, insulin/glucagon production
- LUQ
Large bowel path
begins at cecum - ascending colon - hepatic flexure - transverse colon - splenic flexure - descending colon - rectum
What are the great vessels?
- Aorta - enters at T12 and at L4, divides into iliac arteries
- IVC - runs along side aorta in abdomen getting blood from iliac veins
Major organs in RUQ
- liver
- gallbladder
- right kidney
- pancreas
Major organs in RLQ
- appendix
- right ureter
- reproductive organs
Major organs in LUQ
- spleen
- left kidney
- part of stomach/liver
Major organs in LLQ
- left ureter
- reproductive organs
What are the 9 regions of the stomach
left hypochondriac, epigastric, right hypo,
left lumbar, umbilical, right lumbar
left iliac, hypogastric, right iliac
Where is Broca’s area located?
frontal lobe - controls language production
Where is Wernicke’s area located?
temporal lobe - controls comprehension of language
How are arteries and veins different in structure and function?
- arteries carry blood under more pressure than veins
- arterial walls have thicker muscular coats and more elastic tissue than veins
- veins have valves to assist in one way flow
- veins have a storage function for blood
- arteries play a major role in providing resistance to flow by dilation/constriction
- arteries carry blood away from the heart, veins carry blood to the heart
Why could a pt who has sustained a heart attack have a fall in blood pressure during transport?
The coronary arteries supply the muscle of the heart, and they lack anastomotic channels. For this reason if one of the coronary arteries is blocked, the area supplied by that artery is without oxygen and becomes non-functional
Explain the two special features which differentiates cardiac muscle from other muscle
- Plateau on the action potential which causes contraction for the duration of the plateau
- Repetitive discharges which lead to a tendency for rhythmic contraction
Why is the SA node the pacemaker of the heart?
The SA node has a higher intrinsic rate of discharge than other sites
The clinical aim of shock therapy is to restore what two processes at the cellular level?
Oxygenation and perfusion
What is the etiology of metabolic acidosis seen with shock?
Decreased oxygen delivery to cells results in metabolism without oxygen: glycolysis leads to pyruvate production, which is metabolized to lactic acid, creating metabolic acidosis
What is the approximate total blood volume of a healthy 100kg man?
7 L
Which 4 primary body systems are affected in anaphylactic shock?
- Respiratory
- Integumrntsry
- GI
- Circulatory
Clinical findings particular to cardiogenic shock are:
- pulmonary edema
- JVD
Name the two main hormones which act on the kidney to regulate fluid and electrolyte balance
Antidiuretic hormone (ADH) and aldosterone
Explain the rationale for using normal saline rather than 5% D/W for infusion on the volume-depleted pt
More normal saline than 5% D/W stays in the intravascular space, since normal saline is isotonic and 5% D/W becomes hypotonic once the dextrose component is taken up by cells
State the response of the lungs and kidneys to low and high blood pH
Lungs:
- low blood pH = hyperventilation (exhale excess acid as CO2
- high blood pH = hyperventilation (retain acid as CO2)
Kidneys:
- low blood pH = excrete H+ ions (acid), retain HCO3- ions (base)
- high blood pH = excrete HCO3- ions, retain H+ ions
What is the normal range of blood pH?
7.35-7.45
What are the two functions of the reticular activating system?
- control of wakefulness and consciousness
- responsible for the protective mechanism of the arousal reaction in response to certain stimuli
Which part of the brain coordinates muscle tone and movement?
Cerebellum
All venous blood from the brain drains into the:
Internal jugular vein
What is the effect on the heart when stimulated by the sympathetic division of the autonomic nervous system?
Increases HR
The three general causes of seizure include:
- Metabolic
- Traumatic
- unknown (idiopathic)
Which two groups of individuals are more likely to develop a chronic subdural hematoma?
- the elderly
- alcohol abusers
The general causes of cerebral ischemia include:
- Thrombosis
- Embolism
- Hemorrhage
Why does the pain of cholecystitis often increase on inspiration?
The gallbladder contacts the liver inferiorly. The liver contacts the diaphragm superiorly
- during inspiration the diaphragm descends, increasing downward pressure and often pain
What is a mixed gland?
A gland with both endocrine and exocrine function (I.e. pancreas)
What is a double gland?
A gland consisting of at least two major component which differ in their hormone production (pituitary gland)