CFRN Exam 325 Questions with Verified Answers
What htz would you expect to see flicker vertigo? - CORRECT ANSWER 5-20 htz
Will see at slower speeds such as shutdown & idle.
At 18,000 ft, mean sea level 380 tore,
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CFRN Exam 325 Questions with Verified Answers
What htz would you expect to see flicker vertigo? - CORRECT ANSWER 5-20 htz
Will see at slower speeds such as shutdown & idle.
At 18,000 ft, mean sea level 380 tore, what is the partial pressure of oxygen? - CORRECT ANSWER 80
Atmospheric pressure * 0.21 = partial pressure of O2
360 * .21
PO2 - CORRECT ANSWER Partial pressure of O2 in the ENVIRONMENT.
PAO2 - CORRECT ANSWER Partial pressure of O2 in ALVEOLI.
PaO2 - CORRECT ANSWER Partial pressure of O2 in ARTERIAL blood.
How many total ATP are there at the end of the electron transport chain? - CORRECT ANSWER 36 total. We make a total of 38, but utilize 2 between glycolysis & the Krebs cycle.
SaO2 - CORRECT ANSWER Amount of hgb in the blood that are saturated.
SpO2 - CORRECT ANSWER Total saturation of O2 bound to hgb. What is going on with each individual hgb molecule.
SvO2 - CORRECT ANSWER Mixed venous O2 saturation. What is the consumption? Can only be measured from a PA catheter.
CaO2 - CORRECT ANSWER Total content of O2 bound to hgb.
DO2 - CORRECT ANSWER Delivery of O2 each minute.
(CaO2 x CO)
Product of SaO2, Hgb, Cardiac Output
ScvO2 - CORRECT ANSWER Central venous O2 saturation. Drawn off distal port of central line. Will be 5-8% higher.
Where is CO2 produced? - CORRECT ANSWER Krebs Cycle
How many ATP are produced in anaerobic metabolism? - CORRECT ANSWER 2
Anaerobic metabolism never get to electron transport chain. Goes continuously back & forth between glycolysis & Krebs cycle.
Aerobic is dependent on these 4 things. - CORRECT ANSWER - adequate O2 delivery
- ability to carry O2 (Hgb)
- ability to move O2 (cardiac output)
- ability to extract O2 to cells
Bohr Effect
(OxyHgb Dissociation Curve) - CORRECT ANSWER Hgb O2 binding affinity is inversely related to both acidity & the concentration of CO2.
Right Shift - CORRECT ANSWER Raised acid, raised CO2, raised temp, raised 2-3 DPG, raised PaO2
Right, Raise, Release
Left Shift - CORRECT ANSWER Low temp, low acid, low 2-3 DPG, low PaO2
Left, lower, lock
Pt sat 87%, what would approx PaO2 be? - CORRECT ANSWER 50%
4-5-6 7-8-9 Rule
PaO2 40 = SpO2 70%
PaO2 50 = SpO2 80%
PaO2 60 = SpO2 90%
ETCO2 is a direct reflection of _______________. - CORRECT ANSWER Perfusion
3 P's of low ETCO2 - CORRECT ANSWER Fix the cause, don't just treat the number.
P: Pulse - make sure you have one.
P: Perfusion - what's the MAP. <65 is not a perfusing pressure.
P: pH - decreased. Severe metabolic acidosis (ethylene glycol ingestion, ASA OD, DKA). Pt will compensate & have partially compensated metabolic acidosis.
If have to intubate, target ETCO2 to pre-intubation levels as that indicates what the body really needs.
For every 10mmHg change in CO2, pH changes by _____ in same or opposite direction. - CORRECT ANSWER 0.08 in opposite direction.
For every 10 mEq change in HCO3-, the pH changes by _____ in the same or opposite direction. - CORRECT ANSWER 0.15 in same direction.
For every change in pH of 0.10, the K+ will change by _____ in the same or opposite direction. - CORRECT ANSWER 0.6 in opposite direction.
For every 10 mEq K+ admin, serum K+ increases by _____. - CORRECT ANSWER 0.1
GOLDMARK
(Causes of Acidosis) - CORRECT ANSWER G: glycols (ethylene glycol, propylene glycol)
O: oxyprolene (metabolite from Tylenol OD)
L: l-lactate (lactate levels)
D: d-lactate (by-product of propylene glycol)
M: methanols
A: ASA OD
R: renal failure
K: ketoacidosis
Which acid-base buffering system works minute by minute? - CORRECT ANSWER Respiratory
Which acid-base buffering system works second to second? - CORRECT ANSWER Carbonic acid-bicarb
Mass transfusions — citrate - CORRECT ANSWER A lot of citrate in blood products. It destructs 2-3 DPG.
Also binds to calcium & mag. Therefore always give calcium gluconate (or ca chloride) & mag to hemorrhagic trauma pt.
Also destroys stress hormones - vasopressin & cortisol.
Corrected anion gap formula - CORRECT ANSWER [Na - (Cl + HCO3)] + K
Normal corrected anion gap range - CORRECT ANSWER 16-20
ARDS - Vent Settings - CORRECT ANSWER - High peep to overcome alveolar collapse.
- High fiO2
- Lower tidal volumes 6ml/kg
ARDS
Common Causes - Direct - CORRECT ANSWER Direct Lung Injury
- pneumonia
- aspiration
- near drowning
- inhalation injuries
- pulmonary contusion
- pulmonary edema from reperfusion
ARDS
Common Causes - Indirect - CORRECT ANSWER Indirect Lung Injury
- sepsis
- trauma from shock
- CABG
- drug overdose
- blood product administration
- acute pancreatitis
ARDS Criteria - CORRECT ANSWER - Acute Onset
- Bil infiltrates on CXR
- PAWP <18 mmHg
- PaO2/FiO2 <200 = ARDS
- PaO2/FiO2 <300 = ALI
How to determine good quality CXR
RIP - CORRECT ANSWER R - rotation: pt upright & centered. Spinous process line up, clavicles even.
I - inspiration: look at diaphragm. Which anterior rib intersects diaphragm at midclavicular line. Should be 5-7. Less than 5 = under inflation. Greater than 7 = hyperinflation or something in lung field.
P - penetration: should be able to see vertebrae in front of or behind heart.
Chronic Bronchitis - CORRECT ANSWER - No destruction of lower airways.
- Excessive mucous production.
- Hypoxemia
- Polycythemia due to increased circulating RBC's to increase carrying capacity of O2 in blood.
- Increased CO2 retention.
- May have rt heart failure. Fatigue, edema, exertional dyspnea.
"Blue Bloaters"
Emphysema - CORRECT ANSWER - Destruction of distal airways decreases the ability to oxygenate.
- V/Q mismatch limits blood flow through oxygenated lung d/t destruction of distal airways.
- Compensation occurs by decreasing CO & increasing ventilation, hyperventilation.
- Prevention of fresh air coming into lungs & preventing blood flow to capillaries d/t V/Q mismatch d/t destruction of lower airways.
COPD X-Ray - CORRECT ANSWER - Flattened diaphragm
-should still see curve & costophrenic angle.
- Hyperinflation
- Increased AP diameter of chest in lateral view.
- Long, narrow heart.
- Abnormal air collections.
- Diff to see vertebrae over heart.
COPD
Capnography Waveform - CORRECT ANSWER Shark fin d/t resistance to exhalation
Emphysema X-Ray - CORRECT ANSWER - Hyperinflation
- Flattening of hemidiaphragm
- Small heart
Pt with acute onset dyspnea, PAWP 8, CXR with bil infiltrates. What is the most appropriate diagnosis? - CORRECT ANSWER ARDS
Tension Pneumothorax - X-Ray - CORRECT ANSWER - Vascular marking on affected side may not be visible.
- Mediastinal & tracheal deviation towards contralateral (unaffected) side.
- Ipsilateral (affected) heart border flattening.
Tension Pneumothorax
Assessment - peak airway pressures - CORRECT ANSWER Sudden spike.
Maintain plateau pressure <30.
Tension Pneumothorax
Needle Decompression Landmark - CORRECT ANSWER 2nd - 3rd intercostal space over the rib.
Chest tube size - CORRECT ANSWER 4 x ETT size
Chest Tube insertion
Landmark & positioning - CORRECT ANSWER - supine or 45 angle
- abduct & externally rotate arm on affected side (arm up & behind head).
- 5th intercostal, mid-axillary line.
NG Position - CORRECT ANSWER - >10 cm distal to gastroesophageal junction
- Below left hemidiaphragm
ETT Position - CORRECT ANSWER - 5 cm +/- 2 cm above carina
- at the level of or just below medial ends of clavicle
CVC Position - CORRECT ANSWER - Depends on side of entry & intended use.
Right - 1 - 1.5 cm above level of carina.
Left - below carina to get natural curve into vena cava. If left too high, will irritate wall of vena cava.
Chest Tube Position - Pneumo - CORRECT ANSWER - 5th intercostal space, midaxillary line
- tube tip positioned upper pleural cavity.
- tube pointing up.
Chest Tube Positionjng - Pleural Effusion - CORRECT ANSWER - tube tip lower pleural cavity.
- tube pointing down.
Chest tube insertion
>= 1500 ml fluid returned with insertion. - CORRECT ANSWER Clamp tube to prevent re-expansion pulmonary edema due to rapid inflation/emptying of lung. Leave clamped until arrive at destination.
ECG Changes with P.E.
S I
Q III
T III - CORRECT ANSWER S I - deep S wave lead I
Q III - pathologic Q wave lead III
T III - T wave inversion lead III
ECG Changes with P. E. - CORRECT ANSWER S I
Q III
T III
- Tachycardia
- RBBB
- Rt ventricular strain pattern - t-wave inversion leads V1-V4.
- Rt atrial enlargement - peaked p wave (>2.5 mm) lead II.
- Non-specific ST segment & T wave changes.
Pathologic Q wave criteria - P.E. - CORRECT ANSWER >1 mm or 0.04 sec in width
>2 mm deep
>25% of R wave height
RSI Indications - CORRECT ANSWER - Failure of airway maintenance/protection
- Failure of oxygenation/ventilation
- Anticipated clinical course (multiple trauma, head injury, intoxication, air transport)
Tidal Volume (Vt) - CORRECT ANSWER Normal volume of air inspired during each normal quiet respiratory cycle.
Should be sufficient to overcome dead space & supply the alveoli with oxygen.
Tidal Volume (Vt)
Normal Value - CORRECT ANSWER 6-8 ml/kg
Two types of lung patients - CORRECT ANSWER Obstructive - COPD, Asthma
Injured - trauma, etc.
Respiratory treatment for obstructive lung patient. - CORRECT ANSWER Optimize exhalation: Well-sedated, decrease RR. May also use 8 ml/kg Vt.
Minute Ventilation (VE) - CORRECT ANSWER Volume of any gas or fluid moved per minute.
Vt x RR = VE
Avg 4-8 L/min (same as cardiac output)
Sudden drop in exhaled tidal volume (Vte) - CORRECT ANSWER Leak
Gradual drop in exhaled tidal volume (Vte) - CORRECT ANSWER Air trapping
Exhaled tidal volume (Vte) - CORRECT ANSWER Most accurate measurement of volume received by pt.
Should be within +/- 50 of set Vt.
Only available in volume setting on ventilator.
Trigger - CORRECT ANSWER AKA sensitivity
Set range from low to high with the lower number representing an easier amount of force to initiate breath; the higher the number, the more effort to trigger breath.
Pressure trigger - CORRECT ANSWER Pt has to draw in certain amount of pressure (usually -2 or -3) to trigger a breath. Based on mode, it will either deliver the breath or allow pt the ability to take a spontaneous breath.
Peak Pressure (PIP) - CORRECT ANSWER Only used in volume controlled ventilation.
Measurement of pressure at upper airway, ETT, vent circuit, bronchial tree.
Always the highest pressure on vent.
Peak Inspiratory Pressure (PIP)
Normal value - CORRECT ANSWER Keep <40 cm H2O
Peak Inspiratory Pressure (PIP)
Things that affect value - CORRECT ANSWER - Overall volume going down airway
- How fast volume is going in
- Compliance
- How narrow airway is
- Size of ETT
- Suctioning
- Circuit
What is the most important pressure in ventilated patient? - CORRECT ANSWER Plateau pressure (Pplat)
Plateau pressure (Pplat) - CORRECT ANSWER Measurement of pressure at alveolar level.
Keep <30 cm H2O
Causes of increased plateau pressure (Pplat) - CORRECT ANSWER - Anything that compresses lung bases.
- Trendelenberg
- Ascites
- Abd compartment syndrome
- Obesity with supine position
- Pregnancy
- Increased Vt
- ARDS
- Tension Pneumo
- Pulmonary edema
- Pleural effusion
PIP 48, Pplat 18
What could be the cause? - CORRECT ANSWER Upper airway issue as PIP is high, Pplat is ok.
PIP 48, Pplat 38 in trauma pt.
What is the cause & treatment? - CORRECT ANSWER Tension pneumo.
Immediate needle decompression.
PIP 48, Pplat 38 non-trauma pt.
Causes? - CORRECT ANSWER Fluid in lungs
Ascites
And compartment syndrome
If Pplat elevated, what do you do? - CORRECT ANSWER 1. What's the patho? Correct anything you can.
2. By: Decrease by 1 ml. Then re-check Pplat. If remains high, decrease by 1 again & re-eval. Only decrease to 4 ml/kg. If no change, see #3.
3. Change from volume to pressure delivery.
- start at 20 for adult
- 10-15 for ped.
Absorptive Atelectasis - CORRECT ANSWER Nitrogen sits in alveoli after O2 is diffused resulting in intrinsic PEEP 3-5. High concentration O2 causes nitrogen washout. Need to maintain PEEP to prevent absorptive atelectasis.
Respiratory Cycle Time
Calculation in regards to I:E ratio - CORRECT ANSWER RR = 10
Cycle time = 60 sec
10/60 = 6 sec.
I:E — 1:2
Insp time 2 sec
Exp time 4 sec
Total 6 sec
Changing resp rate will change I:E ratio
Why would you clamp an ETT when moving pt from referral ventilator to transport ventilator? - CORRECT ANSWER Maintain recruitment.
Quickest way to increase oxygenation - CORRECT ANSWER PEEP
PEEP Definition - CORRECT ANSWER Pressure applied to airway at end expiration to maintain alveolar recruitment.
Gas Laws in relation to PEEP (2) - CORRECT ANSWER Henry's Law - make alveoli bigger for more diffusion potential.
Fick's Law — make alveolar membrane thinner to allow better diffusion.
Complication of PEEP - CORRECT ANSWER Decreased venous return.
Variable Rise Time - CORRECT ANSWER - How long does it take to get to its peak pressure.
Ex. Going to Disney on vacation
- How long to get there = rise time
- How long stay at Disney park = Itime
- Only in pressure mode.
- Default = profile 4 = 0.237 sec (time breath delivered.
Causes of slower rise time (Profiles 5-9) - CORRECT ANSWER - Small ETT
- Bronchospasm
- Pressure overshoot
Causes of faster rise time (Profilea 1-4) - CORRECT ANSWER - Short Itime
- Hypoxic - air starved
- Bipap (rise time 1)
Flow Termination - CORRECT ANSWER - How the vent knows when to terminate a spontaneous breath in SIMV.
- select % of peak Inspiratory flow at which PS breaths are terminated.
- only applies to SIMV & spontaneous breaths.
- Ex: vent set to terminate breath at 40%.
Flow set at 100 L/min
40% of total flow - terminates once is reaches 60 L/min
- can regulate TV by regulating flow termination.
- ex: flow term 40% of 100 L/min
Terminates incentive flow reaches 60 L/min.
Flow term 10%
Terminates once flow reaches 90 L/min vs 60 L/min at flow term 40%.
Assist Control - CORRECT ANSWER - Volume or pressure controlled
- Delivers preset tidal volume & RR
- Delivers preset Vt with each triggered breath.
- Need to be very cautious with auto-triggering. Ex. If trigger (sensitivity) set too low, can shake tubing & trigger vent. Can even have triggering by vibration of aircraft. Can cause air trapping.
SIMV - CORRECT ANSWER - Volume or pressure
- Pt receives set number of breaths at a preset tidal volume, allowing for spontaneous breathing between mandatory breaths.
- Pt able to trigger own breath based on sensitivity.
- Can add pressure support (little "boost" at end of circuit that "helps along" pt spontaneous breath).
- The first breath of every cycle is assisted. Every breath after in each cycle is whatever pt wants. Saves from auto-triggering.
SIMV Indications - CORRECT ANSWER - Often used with PS.
- Weaning
- Increased comfort
- Decreased chance of hyperventilation
SIMV
Potential Complication - CORRECT ANSWER Increased muscle fatigue
Indications for Assist Control ventilation - CORRECT ANSWER - Normal respiratory drive accompanied by conditions causing increased work of breathing.
- Apneic patient
Pressure Support - CORRECT ANSWER - Used with AC or SIMV
- Gives pt a little "boost" when taking their own breath.
- Way breath delivered.
Pressure Support - starting pressure - CORRECT ANSWER 10 cm H2O
Pressure Support
1 cm H2O = ? ml of potential SpVt - CORRECT ANSWER 75-150
Pt should not have greater than how much SpVt of pressure support? - CORRECT ANSWER 75%
What to do if SpVt > 75% in pressure support. - CORRECT ANSWER 1. Turn up sensitivity.
2. More sedation.
3. Turn down PS level by 1 cm H2O.
Pressure Regulated Volume Controlled Ventilation (PRVC) - CORRECT ANSWER - often uses with children
- used with AC or SIMV
- constant pressure applied throughout inspiration (like pressure control) regardless of whether breath is a control breath or assist breath.
Pressure alarm on vent should be set at? - CORRECT ANSWER 35 as to not increase pressure beyond.
Injury Strategy approach to ventilation - CORRECT ANSWER - Protects lungs from further injury.
- Mode: AC, IMV
- Delivery method: Volume, PC or PRVC
- Tidal volumes = protection
- Why? Injured lungs are baby lungs
- should not be altered to fix ventilation.
- should only be altered for lung protection & to prevent barotruama. Look at Pplat.
IBW
Calculation - shortcut - CORRECT ANSWER 5'0" = 50 kg
Multiply 2x for every inch above 5'0" of estimated pt height.
Ex. 5'10" = 10" above 5'
10 x 2 = 20
50 kg + 20 = 70 kg IBW
Obstructive Strategy to ventilation - CORRECT ANSWER - Goal is to give as much excitatory time as possible.
- decrease RR to 10-12/min
- lengthen I:E ratio
- Pts have air trapping/auto Peep problems
- decreases venous return
- impedes exhalation
- impedes spontaneous ventilations
- Mode: AC, SIMV
- Delivery: Volume, PC, PS
- Vt: 6-8 ml/kg
- RR: 10-12
- I:E ratio: 1:4, 1:5
- PEEP: 0-3
- Keep <75% of auto-peep
What is the highest pressure on a vent? - CORRECT ANSWER PIP
What is the most important pressure to monitor? - CORRECT ANSWER Pplat - indicates alveolar health.
What type of setting applies only to spontaneous breaths? - CORRECT ANSWER PS
Corrected Sodium Formula - CORRECT ANSWER Measured NA +. (Serum glucose-100)0.016
For every 0.1 change in H+, K+ will change by _______ in same or opposite direction. - CORRECT ANSWER 0.6 in opposite direction
For every 10 mmHg change in CO2, pH will change by ______ in same or opposite direction. - CORRECT ANSWER 0.08 in opposite direction
For every 10 meq change in HCO3-, pH will change by in same or opposite direction. - CORRECT ANSWER 0.15 in same direction
What hormones does the hypothalamus produce? - CORRECT ANSWER ADH, Oxytocin & Regulatory hormones
What hormones does the anterior lobe of the pituitary gland produce? - CORRECT ANSWER ACTH, TSH, GH, PRL, FSH, LH & MSH
What hormones does the posterior lobe of the pituitary gland excrete? - CORRECT ANSWER Release of oxytocin & ADH
What hormones does the thyroid gland excrete? - CORRECT ANSWER Thyroxine (T4), Triiodothyronine (T3), Calcitonin
What hormones do the parathyroid glands release? - CORRECT ANSWER Parathyroid hormone (PTH)
What hormones does the thymus release? - CORRECT ANSWER Thymosins
(Thymus undergoes atrophy during adulthood.)
What hormones are released by the heart? - CORRECT ANSWER Natriuretic Peptides: ANP & BNP
What hormones are released by the adrenal medulla? - CORRECT ANSWER Epinephrine & Norephinephrine
What hormones are released by the adrenal cortex? - CORRECT ANSWER Cortisol, corticosterone, aldosterone, androgens
What hormones are released by the kidneys? - CORRECT ANSWER Renin, Erythropoietin, Calcitriol
What hormones are released by adipose tissue? - CORRECT ANSWER Leptin & Resistin
What hormones do the pancreatic islets release? - CORRECT ANSWER Insulin, glucagon
What hormones are released by the testes? - CORRECT ANSWER Androgens (esp testosterone), inhibin
What hormones are released by the ovaries? - CORRECT ANSWER Estrogens, progestins, inhibin
Serum Osmolality
(Definition) - CORRECT ANSWER Measure of concentration - number of solutes in comparison of H2O or fluid in plasma/serum.
Serum Osmo increased = more solutes in comparision to fluid = dehydration.
Serum Osmo decreased = more fluid/H2O in comparison to solutes = Over-hydrated
Serum Osmolality
(Normal Value) - CORRECT ANSWER 275-295 mOsm/kg
What is ADH & where is it stored? - CORRECT ANSWER Anti-diuretic hormone = no urine. Causes body to hold onto fluid; causes H2O retention.
Normally secreted in response to serum osmolality level.
Stored in post pituitary gland.
SIADH - CORRECT ANSWER Get secretion of ADH despite serum osmolality levels -> water retention.
Alters fluid & e-lyte balance.
SIADH
Findings - CORRECT ANSWER -Dilutional hyponatremia - shifts fluid from outside cells to inside cells. Therefore, pt does not appear edematous.
-Concentrated urine - S.G. > 1.030; dark urine
-Na < 135
-Serum Osmo < 270
- May complain of diff breathing d/t pulmonary edema.
-Cerebral edema d/t shift of fluid inside brain cells. Sx may mimic CVA.
-Seizures - may be intractable d/t hyponatremia; not responsive to benzos; will not stop until Na corrected.
SIADH
Causes - CORRECT ANSWER -Carcinomas of the lung, esp oat cell carcinoma d/t substance that is indistinguishable from ADH with the body. Acts the same way as ADH.
-Nephrogenic/nephrotoxic drugs, esp. acetaminophen, Elavil, anesthetics.
-Hypoxemia
-Increased stress environment - ex. ICU pt.
-Head problems - trauma, tumors, meningitis, CVA, encephalitis.
-Viral/Bacterial pneumonia (& other pulmonary disorders).
SIADH
Treatment - CORRECT ANSWER -Fluid restriction
-Hypertonic saline - 1-2 ml/kg/hr if Na < 105 for the first 3-4 hours or until sx subside. (Hypotonic solutions cause H2O to enter cells.)
-D5W = osmo of 272 in container = left with hypotonic saline because body quickly uses glucose.
-Lasix 1 mg/kg
-Raise Na 0.5 mEq/L an hour. Raise/lower Na slowly to prevent rapid change in volume. Exception, may have to rapidly raise Na to stop seizures.
Who gets Diabetes Insipidus? - CORRECT ANSWER -Head Injury
-Pituitary Tumor
-Infection
-Drug Induced - Dilantin, Lithium, Amphotericin B
Diabetes Insipidus
Symptoms - CORRECT ANSWER -Dehydration
-Dry mucous membranes
-Tachycardia
-Sunken fontanelles
-Excessive thirst
-Electrolyte Imbalance
-Fatigue, lethargy
-HA
-Irritability
-Muscle pains
Diabetes Insipidus
Definition - CORRECT ANSWER -Opposite of SIADH = low levels of ADH
-Large loss of H2O >6L/day
-Lab findings:
-Na increased
-Serum Osmo increased
-Specific gravity decreased
Results in: hypovolemia, shock, electrolyte imbalance.
Diabetes Insipidus
Treatment - CORRECT ANSWER -Aggressive IVF replacement
-Vasopressin (synthetic ADH)
-Desmopressin (DDAVP) - not as vasoconstrictive as vasopressin.
-Monitor urine specific gravity.
-Monitor for cardiac changes.
Diabetes Type 1 - CORRECT ANSWER No insulin production d/t destruction of beta cells in pancreas.
Most common in juveniles.
Diabetes Type 1
Symptoms - CORRECT ANSWER -Polyuria
-Polydipsia
-Polyphagia
-Unexplained weight loss
Less common sx: fatigue, nausea, blurred vision.
Regular Insulin
Onset, duration - CORRECT ANSWER IV onset - immediate
SQ onset - 20-30 min
Duration - 4-12 hours
Diabetes Type 2
Causes - CORRECT ANSWER -Resistance to action of insulin
-Inadequate insulin secretions
-Inadequate glucagon secretions - too much secreted.
Diabetes Type 2
Symptoms - CORRECT ANSWER -Polyuria
-Polydipsia
-Polyphagia
-Weight loss
-Lower ext paresthesias
-Blurred vision
-Yeast infections
Diabetes Complications - CORRECT ANSWER -CV disease
-Neuropathy (generally begins in toes & works way up legs)
-Nephropathy d/t damaged glomerula
-Retinopathy d/t damage of blood vessels in retina.
-Foot damage d/t decreased blood blow -> ulcers -> massive wounds
-Skin & mouth conditions.
Diabetes
Goals of Treatment - CORRECT ANSWER -HbA1C every 3-6 mos.
-Yearly dilated eye exams.
-Annual microalbumin checks to help determine if kidney problems are occurring.
-Foot exams @ every visit.
-BP < 130/80
-Statin Therapy - reduces cholesterol; reduces risk of developing CAD.
DKA
Must have ____________, ____________ & ____________ - CORRECT ANSWER -Hyperglycemia
-Acidosis
-Ketones (blood or urine)
Glucose usually >250
pH <7.3; HCO3 <18
Ketones > 5 meq/L in blood
Usually very dehydrated (4-5 L behind)
DKA
Symptoms - CORRECT ANSWER -State of acidosis
-Ketones cause fruity breath
-Kussmaul resp d/t attempting to blow off CO2
-Potassium loss
-Dilutional hyponatremia (increased serum osmo - glucose pulls H2O towards it)
-Altered LOC
-Corrected sodium
-measured sodium + [0.016 + (serum glucose - 100)
Why do you want a higher K+ in a DKA pt? - CORRECT ANSWER Hydrogen (strong ion) goes into the cell to help correct acidosis. Pushes K+ out of the cell to help maintain balance -> initially, increased K+. As DKA progresses, lose K+ in urine.
Corrected Sodium Equation - CORRECT ANSWER Measured Na + (serum glucose - 100)0.016
For every 100 mg/dl of glucose over 100, Na+ drops by 1.6 mEq/L
As soon as you begin fluid resuscitation & give insulin, Na+ will rise.
Ex: Na+ 110, glucose 1848
110 + (1748)0.016 = 138 corrected Na+
For every change of 0.1 in H+, the K+ will change ____ in the same or opposite direction? - CORRECT ANSWER 0.6; opposite
For every 10 mmHg change in CO2, the pH will change ____ in the same or opposite direction? - CORRECT ANSWER 0.08; opposite
For every 10 mEq change in HCO3-, the pH will change by _____ in the same or opposite direction? - CORRECT ANSWER 0.08; same
pH, CO2, HCO3 example 1 - CORRECT ANSWER pH 7.15, PaCO2 17, PaO2 89, HCO3 6, K 3.5
Give pt HCO3 & HCO3 increases to 16.
-HCO3 now 16
-pH now 7.3 (for every 10 mEq change in HCO3, the pH will change by 0.15 in the same direction)
-K now 2.6 = bad!
pH, CO2, HCO3 example 2 - CORRECT ANSWER pH 7.15, PaCO2 17, PaO2 89, HCO3 6, K 3.5
-CO2 increased to 27
-pH now 7.07
-K now ~4.0
Diabetes
Key Points - CORRECT ANSWER -When giving insulin, you will drive glucose, K+ & H2O back into the cell. Therefore, important to hydrate pt.
-Do not drop glucose more than 100 mg/dL/hr. Glucose is large molecule & hyperosmolar. Rapid drops will cause third-spacing of fluid back into the tissue, especially the brain -> cerebral edema. May cause irreversible damage.
-If glucose decreases too fast, cut insulin dose in half. Can also give D50 for rapid, significant drops.
-K+ want on high to high-normal side. Once insulin starts, K+ will go back into cell.
-HCO3- not generally given in DKA, only in certain circumstances.
-Lactate often metabolized to HCO3- once tx starts, therefore will see increase in HCO3-.
-HCO3- admin can also lead to K+ being shifted into cell.
For every 0.6 change in K+, the pH will change by ____ in the same or opposite direction? - CORRECT ANSWER 0.1; opposite
For every 0.15 change in pH, HCO3- will change by ____ in the same or opposite direction? - CORRECT ANSWER 10 mEq; same
For every 0.08 change in pH, the CO2 will change by ____ in the same or opposite direction? - CORRECT ANSWER 10 mmHg; opposite
HHNK
Who gets it? - CORRECT ANSWER - Elderly d/t tired pancreas
-New or uncontrolled diabetes, usually Type 2
-Those on TPN
-Pancreatitis = 95% mortality
-overuse of thiazides - they hold onto glucose
-overuse of steroids - leads to insulin resistance
-Infection
-Stress
HHNK
What makes it different from DKA? - CORRECT ANSWER -No acidosis
-Higher blood sugar ranges (1000-2000)
Blood sugar continues to rise because they don't have the acidosis that usually makes people seek treatment.
HHNK
Symptoms - CORRECT ANSWER -Weakness
-Altered MS
-Neurological changes
-Dehydration (8-10 L/day) - glucose is hyperosmolar & pulls H2O towards it.
-Polyuria
-Shallow breathing
-Hypernatremia
HHNK
Treatment - CORRECT ANSWER Similar to DKA
-Fluid replacement is first line therapy. Fluid deficit may be as large as 10L or more.
-Add dextrose to prevent precipitous drop in glucose once BS ~300.
-Insulin administration
-0.1 units/kg bolus & gtt at same rate
-Do not drop glucose >100/hr
-K+ repl - same as DKA
-start w/K+ 5.0-5.5
*Always make sure to check blood sugar!
*Always be sure to check other things - K+, etc.
Thyroid Storm
Definition - CORRECT ANSWER Acute, life-threatening exacerbation of thyrotoxicosis.
Excess production of thyroid hormone.
Thyroid Storm
Symptoms - CORRECT ANSWER -Hyperpyrexia - up to 104
-Diaphoresis initially. Will decrease as dehydration ensues.
-Tachycardia (may present as AF)
-N/V/D
-Tremulousness & delirium
-Confusion
-Possible sz.
Extremely high metabolism. O2 demands quickly exceeds supply. Will quickly go into anaerobic state.
May be precipitated by many different factors.
Thyroid Storm
Labs - CORRECT ANSWER TSH - suppressed
Free T4 - elevated
T3 - elevated
Thyroid Storm
4 goals of therapy - CORRECT ANSWER 1. Block formation of new hormones in thyroid gland.
2. Inhibit the action of hormones already formed.
3. Support vital functions.
4. Identify & treat precipitating event.
Thyroid Storm
Treatment - CORRECT ANSWER Mainstay of treatment is anti-thyroid meds to prevent production of T4 to T3 and inhibit inactive hormone to active hormone:
-PTU - side effect = decreased platelets
-Metamizole
Administer glucocorticoid - d/t depletion of cortisol levels d/t stress. Also blocks production of T4 & T3. Also supports BP & prevents adrenal insufficiency.
-Solumedrol
-Dexamethasone
-Solu-Cortef
Administer B-adrenergic blocking agent. Helps decrease HR & tremors.
-Esmolol
-Propanolol
Supportive care
-Fever - Treat with acetaminophen. NO ASA because ASA will increase amount of active circulating hormone.
Myxedema Coma
Definition - CORRECT ANSWER Extreme manifestation of hypothyroidism.
More common in winter months.
Myxedema Coma
Symptoms - CORRECT ANSWER -Altered mentation
-Alopecia
-HTN (early), hypotension (late)
-Bradycardia
-Delayed reflex relaxation
-Dry, cool, doughy skin
-Hypothermia (80%)
-Myxedematous face
-Hair dry, coarse, sparse
-Lateral eyebrows thin
-Periorbital edema
-Puffy dull face w/dry skin
Myxedema Coma
Labs - CORRECT ANSWER Free T4 & T3 - decreased
TSH - significantly decreased
Myxedema Coma
Treatment - CORRECT ANSWER -IVF
-Corticosteroids d/t high stress states depleting cortisol levels.
**-IV thyroid replacement**
Cushing Syndrome
Causes - CORRECT ANSWER Endogenous - tumor that's over-secreting glucocorticoids. Most likely pituitary tumor.
Exogenous - long-term steroid tx.
Cushing Syndrome
Symptoms - CORRECT ANSWER -Weight gain; "buffalo hump"
-Skin changes (stretch marks, easy bruising)
-Hirsutism
-Menstrual irregularities; amenorrhea
-Impotence
-Osteopenia
Cushing Syndrome
Treatment - CORRECT ANSWER Removal of causative agent
-removal of tumor
-tapering off of glucocorticoids
Adrenal Insufficiency
Definition - CORRECT ANSWER Lack of cortisol; body cannot maintain essential life functions.
-Cortisol helps regulate blood sugar, helps hold back immune response released in response to stress.
Likely to occur in high stress states.
Adrenal Insufficiency
Symptoms - CORRECT ANSWER -Hypotension refractory to fluid admin.
-Aldosterone also produced by adrenal glands. Helps maintain BP & H2O balance. Hypotension despite IVF in adrenal insufficiency.
-Tired/weak
-Dizziness upon standing
-Loss of appetite
-Joint aches & pains
-Hypoglycemia
Adrenal Insufficiency
Treatment - CORRECT ANSWER -Glucocorticoids - hydrocortisone, dexamethasone, prednisone.
-Will also help fluid refractory hypotension.
Cullen's Sign - CORRECT ANSWER Discoloration around umbilicus d/t hemoperitoneum.
Grey-Turner's Sign - CORRECT ANSWER Discoloration over flank areas d/t retroperitoneal bleeding.
What does the pancreas do? - CORRECT ANSWER Mainly responsible for production & release of insulin.
Also significantly aids in release of digestive enzymes to help in the digestive process.
Pancreatitis
Causes - CORRECT ANSWER -Biliary tract disease - gallstone most common.
-Gets stuck in bile duct in sphincter of Odi causing increased pancreatic duct pressure.
- ETOH abuse - most often chronic.
- Trauma
- Certain drugs
- Infection (viral & bacterial)
What are the two types of pancreatitis? - CORRECT ANSWER Interstitial - edematous process, hypovolemia d/t third spacing.
Hemorrhagic - necrosis within pancreas, pancreatic tissue & duct. Erosion into blood vessels leading to increased bleeding. Release of necrotic type enzymes leading to sepsis.
Pancreatitis
Symptoms - CORRECT ANSWER -Cullen's Sign - discoloration around umbilicus d/t hemoperitoneum.
-Grey-Turner's Sign - flank areas d/t retroperitoneal bleeding.
-Erythematous skin nodules - uncommon; palms, soles of feet.
-Fever - most common
-Tachycardia - most common
-Abd tenderness/guarding
-Pain radiating to back
-Jaundice
-Dyspnea d/t irritation on diaphragm from edematous process.
-Pleural effusion/ARDS
-Hematemesis/melena
Pancreatitis
Treatment - CORRECT ANSWER -Fluid resuscitation - lose large amounts of fluid d/t third spacing.
-monitor U/O
-monitor perfusion status
-Antibiotics - Not always used.
-Used in cases of pancreatic necrosis.
-NPO
-Analgesics for pain relief.
Sickle Cell Crisis
Facts - CORRECT ANSWER -Autosomal recessive
-African-American & Africa ancestry.
-Abnormal RBC - crescent shaped
-Carries Hgb S
-Increased risk of infection d/t abn RBC.
Sickle Cell Crisis
Symptoms - CORRECT ANSWER -Severe pain
-Sickled cells build up & cause "clogged area" -> decreased blood flow beyond area = pain.
Sickle Cell Crisis
Treatment - CORRECT ANSWER -Pain Management is biggest priority.
-IVF
-Infection tx if necessary.
-PRBC transfusion if anemia significant.
Acute Renal Failure (ARF)
Definition (U/O) - CORRECT ANSWER Decreased urine output <400 cc/24 hr
Acute Renal Failure
3 main causes - CORRECT ANSWER 1. Pre-Renal
2. Intra-Renal
3. Post-Renal
Acute Renal Failure
Pre-Renal - CORRECT ANSWER Results from any condition "outside" (above) the kidney that impedes blood flow.
-CHF
-Hypotension, possibly d/t significant hemorrhage, decreased CO, dehydration.
*Need sufficient MAP to maintain kidney filtration.
Acute Renal Failure
Intra-Renal - CORRECT ANSWER Anything that causes direct insult to kidney. Causes damage to kidney, parenchyma, nephrons.
-Nephrotoxic drugs
-Acetaminophen OD
-Anesthetics
-Tricyclic anti-depressants
-Hemolysis
-Transfusion reactions
-Rhabdo
Acute Renal Failure
Post-Renal - CORRECT ANSWER Backflow of urine into the renal pelvis.
-Urethral obstruction
-Bladder obstruction
-BPH
-Prostate CA
-Urinary cath obstruction
-Renal calculi
Acute Renal Failure
Symptoms - CORRECT ANSWER -Edema of hands & feet
-N/V
-Confusion
-Flank pain
Acute Tubular Necrosis
Facts - CORRECT ANSWER -Most common intra-renal condition.
-Damage to nephrons leading to changes in urine concentration & filtration leading to electrolyte imbalance.
-Does not improve with rehydration.
Acute Tubular Necrosis
Causes - CORRECT ANSWER -Prolonged ischemia
-Hypotension
-Nephrotoxic drugs
-Obstruction
Acute Renal Failure
Stages - CORRECT ANSWER 1. Onset Phase
2. Oliguric/Anuric Phase
3. Diuretic Phase
4. Recovery Phase
Acute Renal Failure
Onset Phase - CORRECT ANSWER Time from onset of injury through cell death. Can last hours to days.
-U/O declining
-Increased urine Na+
-Decreased renal blood flow.
Acute Renal Failure
Oliguric/Anuric Phase - CORRECT ANSWER Further damage to renal tubular wall & membranes. Usually lasts 8-14 days.
-Most significant phase for patient.
-Significant decrease in GFR.
-Significant increase in BUN & Cr
-Significant electrolyte & acid-base imbalances.
-Increased K+
-Increased Phos
-Decreased Ca+
-Metabolic acidosis
-Mortality increases to 50%
Acute Renal Failure
Diuretic Phase - CORRECT ANSWER Source of obstruction removed, but residual scarring & edema of tubules remains. Lasts 7-14 days.
-Increased GFR
-Significant increase in U/O
-Electrolyte & acid-base imbalance d/t significantly increased U/O.
-Mortality decreases to 25% if pt makes it to this phase.
Acute Renal Failure
Recovery Phase - CORRECT ANSWER Renal tubules begin to function adequately. Can last several months to over a year.
-Edema decreases
-Fluid & electrolyte balance restored.
_GFR returns to "new normal" which is sufficient enough to sustain life.
Clotting Cascade
Step 1 - CORRECT ANSWER Vascular spasm
Smooth muscle contracts causing vasoconstriction in attempt to prevent further blood loss from occurring.
Clotting Cascade
Step 2 - CORRECT ANSWER Platelet plug formation
Injury to lining of vessel collagen fibers, platelets adhere.
Platelets release chemicals that make nearby platelets sticky; constricts & pulls vessel wall in; platelets adhere.
Clotting Cascade
Step 3 - CORRECT ANSWER Coagulation
Convert plasma, fibrinogen to fibrin form.
Fibrin (very sticky protein) forms a mesh that traps RBCs & platelets forming the clot.
DIC - CORRECT ANSWER Overstimulation of clotting cascade secondary to massive tissue damage. Always secondary to another problem.
Production of small blood clots in body that block small blood vessels causing tissue necrosis in areas beyond the clots due to lack of blood flow.
Body uses up all clotting factors during the process = increased risk for bleeding.
DIC
Causes - CORRECT ANSWER -Sepsis
-Post-surgery
-Trauma
-Cancer
-Pregnancy & childbirth
DIC
Treatment - CORRECT ANSWER -Heparin - helps prevent clot formation. Inhibits conversion of some clotting factors to active form, specifically prothrombin to thrombin.
-Blood component replacement
-Anti-thrombin III
-Tranexamic Acid (TXA)
Sepsis
Definition - CORRECT ANSWER Life threatening organ dysfunction caused by a dysregulated host response to infection.
Organ Dysfunction in Sepsis
Definition - CORRECT ANSWER Increase in sequential organ failure assessment (SOFA) score of 2 pts or more resulting from the infection.
Septic Shock
Definition - CORRECT ANSWER -Sepsis with profound circulatory, cellular & metabolic abnormalities.
-Requires vasopressors to maintain MAP >=65 mmHg.
-Serum lactate >2 in absence of hypovolemia. (Pt has already been volume resuscitated.)
aSOFA Criteria - CORRECT ANSWER A means to identify patient at higher risk for in-hospital mortality. Utilized out of hospital & ED.
-RR >=22
-Altered mental status - GCS <15
-SBP 100 mmHg or less
Some also include ETCO2 <25 & initial lactate >4 before fluid resuscitation.
Sepsis Patho - CORRECT ANSWER Inflammatory Cascade (Immune response also releases WBCs)
-Proinflammatory cytokines & mediators
-Capillary leakage due to endothileal damage
-Profound hypotension, refractory hypotension, vasodilation.
-Neutrophils that are released as part of the immune response release nitric oxide which is a potent vasodilator.
Link between inflammation & coagulation
-Clotting cascade is activated to stop leakage.
Severe sepsis - final pathway
-Vasoconstrict down. Can't do it because nitric oxide being released causing vasodilation. Body can't overcome it to vasoconstrict.
-Leads to cardiovascular collapse -> multi-organ failure & to death if not treated in timely manner.
Sepsis Treatment - CORRECT ANSWER Fluid resuscitation - initially 30 ml/kg.
-Recommend crystalloids
-Aggressive in acute phase of sepsis followed by more conservative approach.
-Albumin when needed.
-may decrease morbidity/mortality when a lot of fluid is needed.
-monitor lactate or procalcitonin levels.
Vasopressor treatment (MAP goal >=65)
-First line: Norepi
-Second line: Vasopressin, epinephrine
-May add dobutamine to maximize CO
*Phenylephrine not recommended.
Appropriate ABX within 1st hour.
Control source of infection.
Optimize tissue oxygenation.
Add'l tx:
-Admin of blood products to increase O2 carrying capacity & boost SvO2.
-Stress ulcer prophylaxis - H2 or PPI
Sepsis
Goals of resuscitation within 1st hour - CORRECT ANSWER -CVP 8-12 mmHg (standard)
-CVP 12-15 mmHg (Hx of HTN)
-MAP >=65 mmHg
-U/O >0.5 ml/kg/hr
-Mixed venous oxygen sat (SvO2) 65-70%
Mechanical Ventilation in Sepsis-Induced ARDS - CORRECT ANSWER * - Target TV 6 ml/kg
* - Plateau pressure <30
- PEEP to avoid alveolar collapse & enhance gas exchange.
Protective Layers of the Brain - CORRECT ANSWER Skull
Dura Mater - thick
Arachnoid
Subarachnoid Space
Pia Mater - thin layer surrounding surface of brain
Epidural Space - CORRECT ANSWER Area between skull and dura mater
Subdural Space - CORRECT ANSWER Below dura, above arachnoid space
Subarachnoid Space - CORRECT ANSWER Between arachnoid space and pia mater
Monroe-Kellie Hypothesis/Doctrine - CORRECT ANSWER -Cranial vault is a fixed space.
-3 intracranial components
-Blood
-Brain
-CSF
-Any increase in once component requires a decrease in another.
ICP
Normal Range - CORRECT ANSWER 0-15
MAP
Normal Adult Value - CORRECT ANSWER 70
MAP Formula - CORRECT ANSWER [(DBP x 2) + SBP]/3 = MAP
Does hypocapnia cause vasoconstriction or vasodilatoin? - CORRECT ANSWER Vasoconstriction
Does hypercapnia cause vasoconstriction or vasodilation - CORRECT ANSWER Vasodilation
CPP Formula - CORRECT ANSWER MAP-ICP = CPP
CPP
Normal Value - CORRECT ANSWER 60-100 mmHg
CPP
Target Range: Adult - CORRECT ANSWER >70 mmHg
CPP
Target Range: Pediatric - CORRECT ANSWER >60 mmHg
Triple H Therapy
(H3 Therapy) - CORRECT ANSWER Hypervolemic
-Volume
Hyperdynamic
-Optimize cardiac output
-Dobutamine
Hypertensive
-Levophed
Signs of Increased ICP - CORRECT ANSWER -Change in LOC, pupil size & reaction, motor response
-HTN, tachycardia, cheyne-stokes resp
What is the difference between increased ICP & Cushing's Triad? - CORRECT ANSWER HR
Increased ICP = tachycardia
Cushing's Triad = bradycardia
Cushing's Triad - CORRECT ANSWER - Widened pulse pressure
-Bradycardia
-Irregular respirations (Cheyne-Stokes)
Decorticate Posturing - CORRECT ANSWER Flexion of upper extremities towards the core.
Decerebrate Posturing - CORRECT ANSWER Extension & hyperpronation of upper extremities.
Signs of Herniation - CORRECT ANSWER -Decorticate posturing
-Decerebrate posturing
-Blown pupil
ICP Treatment - CORRECT ANSWER -Limit suctioning procedures
-Decrease noise
-Decrease atmospheric changes
-Fluid balance
-Normothermia
-Normal electrolytes
-Sedation
-Fentanyl, benzos, propofol
-Consider long-acting paralysis
Subdural Hemorrhage (CT Scan) - CORRECT ANSWER Appears as waviness on CT scan - follows contours of brain.
Subdural Hematoma (CT Scan)
Acute - CORRECT ANSWER Less than 72 hours.
Blood appears as white.
Subdural Hematoma (CT Scan)
Subacute - CORRECT ANSWER 3-7 days
Black area within white area. (May just be black area)
Subdural Hematoma
Location - CORRECT ANSWER Between the dura mater and the arachnoid membrane.
Subdural Hematoma
Causes - CORRECT ANSWER -Hypertesive hemorrhage & ruptured aneurysm.
-Traumatic causes that arise from tears of the cerebral veins that connect the subarachnoid space to the dural sinuses.
Subdural Hematoma
Symptoms - CORRECT ANSWER -May have immediate LOC.
-Signs may not appear for days (subacute).
Acute subdural bleeds have a 40-60% mortality rate d/t a significant association with diffuse axonal injury.
Subdural Hematoma
Treatment - CORRECT ANSWER -Advanced airway management
-Maintain ETCO2 30-35 mmHg
-Adequate fluid resuscitation
-Mannitol
-Osmotic diuretic that decreases viscosity of blood & improves microcirculation.
-Lasix
-Serum sodium 155+
-3%-23.4% NS bolus 5-10 ml/kg
-pulls water out of cells, shrinking cells, reduces edema & ICP.
-Serum osmolality <320 = goal
-Barbituates for seizures.
Subdural Hematoma
Serum Osmolality Goal - CORRECT ANSWER <320
Tells cellular hydration. The higher the value, the more cellularly dry. Normal 275-295.
Diffuse Axonal Injuries (DAI)
Definition - CORRECT ANSWER Occurs when nerve fibers are torn or stretched as the result of head impact (frontal-occipital).
What type of injury most often causes DAI? - CORRECT ANSWER Deceleration injuries
DAI
Symptoms - CORRECT ANSWER -Confusion
-Severe HA
-Seizures
-Combativeness
-LOC
-Lower incidence of skull fracture
What is the preferred diagnostic test for DAI? - CORRECT ANSWER MRI - 92% diagnostic
Epidural Hematoma
Location - CORRECT ANSWER Between cranium & dura mater.
What vessel is typically the cause of an epidural hematoma? - CORRECT ANSWER Middle meningeal artery.
Think MMA fighter hits someone in temporal region = MMA = middle meningeal artery.
Pterion region of brain - CORRECT ANSWER Area where all sinuses & planes (frontal, temporal, parietal areas) come together. Weakest area.
Epidural Hematoma
Symptoms - CORRECT ANSWER -Temporary LOC
-Lucid period (may last minutes to hours)
-Recurrent LOC -> rapid deterioration of status.
Seizures possible.
Epidural Hematoma (CT Scan) - CORRECT ANSWER -Appears as circular area because dura is thick.
-Does not follow contours of brain.
-Looks like a pupil.
Pt presents with a traumatic injury & brief LOC. Then has a period of alertness followed by another LOC. What type of injury do you suspect? - CORRECT ANSWER Epidural hematoma
Epidural Hematoma
Treatment - CORRECT ANSWER Rapid decompression
Subarachnoid Hemorrhage
Location - CORRECT ANSWER Bleeding between arachnoid & pia mater membranes.
Most often in Circle of Willis.
Circle of Willis - CORRECT ANSWER -Area where vessels from cerebellum & cerebrum come together.
-Feeds off basilar artery.
-Basilar artery hemorrhage ~90% fatal because supplies almost all blood flow to brain.
Subarachnoid Hemorrhage (CT Scan) - CORRECT ANSWER Blood around Circle of Willis.
Imagine 5 separate roads coming into round-about (center) area.
Subarachnoid Hemorrhage
Symptoms - CORRECT ANSWER -Worst HA ever
-Decreased MS to coma
-Vomiting
-Seizure
Subarachnoid Hemorrhage
Causes - CORRECT ANSWER -Trauma
-Accelerated HTN
-Ruptured berry aneurysms
-Ruptured AVM
Subarachnoid Hemorrhage
Why is anterior communicating artery susceptible? - CORRECT ANSWER Comes off at 90 degree angle making it a weak area.
Subarachnoid Hemorrhage
BP Goal - CORRECT ANSWER SBP 140
Maintain @ 140 instead of 160 d/t high incidence of re-bleeding.
Intraventricular Hemorrhage
AKA? - CORRECT ANSWER Intraparenchymal bleed, intracerbral bleed
Intraventricular Hemorrhage
Causes - CORRECT ANSWER Usually related to some other type of injury - shearing forces.
Intraventricular Hemorrhage
Location of associated injuries - CORRECT ANSWER Frontal & temporal lobe injuries
Intraventricular Hemorrhage
Treatment - CORRECT ANSWER -Prevent further insult
-Maximize CPP >70
-Maintain SBP @ 160
-Control ICP
-Mannitol
-Loop diuretic
What areas of the brain does the intervertebral artery supply? - CORRECT ANSWER Cerebellum
Pons
Brain Stem
Intervertebral Artery Injury
Causes - CORRECT ANSWER -C2 fracture
-MOI that could cause C2 fracture
-scapular injury
-First rib injury
-Stroke
-Dissection
-Can occur @ any age.
Brown-Sequard Syndrome - CORRECT ANSWER Hemisection of cord (usually cervical region).
Brown-Sequard Syndrome
Symptoms - CORRECT ANSWER Reduced or loss of motor on side of lesion.
Temperature & pain function remain.
Reversed on opposite side.
Central Cord Syndrome
Symptoms - CORRECT ANSWER Greater motor weakness in upper extremities than lower with varying degree of sensory loss.
Anterior Cord Syndrome
Symptoms - CORRECT ANSWER Complete motor, pain, temperature loss below lesion with sparing of proprioception (perception of awareness), vibration & touch.
SCIWORA Syndrome
Definition - CORRECT ANSWER Spinal cord injury without radiographic abnomality.
Neurogenic Shock
Definition - CORRECT ANSWER True transection of spinal cord.
Will cause parasympathetic dominance below lesion.
Neurogenic Shock
Symptoms - CORRECT ANSWER -Hypotension
-Flushed/Red Sin
-Absence of tachycardia (may have bradycardia)
Neurogenic Shock
Treatment - CORRECT ANSWER -Give a lot of volume
-Levophed
-Dopamine (esp with presence of bradycardia)
Acute Autonomic Dysreflexia
AKA Neurogenic Bladder - CORRECT ANSWER Potential life-threatening HTN caused by transection of cord above T6.
Body senses pressure, but pt can't feel it.
Acute Autonomic Dysreflexia
Treatment - CORRECT ANSWER -Check foley for kinks.
-Consider other noxious stimuli that may be the cause.
Body senses pressure, but pt can't feel it.
3 Layers of Heart - CORRECT ANSWER -Epicardium - outer layer that contains sm amt fluid (~8-10 cc)
-Myocardium - heart muscle
-Endocardium - inside heart, surrounds chambers & valves.
Tricuspid Valve
Location - CORRECT ANSWER Separates rt atrium from rt ventricle.
Is the tricuspid valve a low or high pressure valve? - CORRECT ANSWER Low pressure d/t being on rt side of heart which is low pressure.
How does passive filling of heart work? - CORRECT ANSWER SA node fires @ 60-100 bpm (primary pacemaker).
-> AV node 40-60 bpm (secondary pacemaker) slows conduction to allow for passive ventricular filling.
Atrial Kick - CORRECT ANSWER -Blood pushed into the ventricles by atrial contraction.
-Accounts for approx 20% of preload. (Other 80% of preload is d/t passive filling.)
Right Atrial Pressure
Normal Range - CORRECT ANSWER 2-6 mmHg
Right Ventricular Pressure
Normal Range - CORRECT ANSWER Systolic 20-30
Diastolic 0-5
Pulmonic Valve - CORRECT ANSWER -3 leaf valve
-Separates rt ventricle from pulmonary artery
-Gateway to oxygenation
*-Maintains diastolic pressure in the pulmonary artery.
-MAP is made up of 2/3 diastolic pressure.
MAP Formula - CORRECT ANSWER [(2 x DBP) + SBP] /3
Mitral Valve - CORRECT ANSWER -Separates left atrium from left ventricle
-High pressure valve
-Bicuspid Valve
Aortic Valve - CORRECT ANSWER -Separates left ventricle from aorta.
-Most important valve to maintain cardiac output.
-Stretches & snaps back during contraction which is aortic kick & important for CO
If aortic valve disease, pt may respond well to fluid volume challenge of 250-500 cc bolus because the aortic valve is preload dependent.
Cardiac Output
Normal Value - CORRECT ANSWER 4-8 L/min
Avg 5.5 L/min
Cardiac Index
Normal Value - CORRECT ANSWER -Calculated on BMI
2-4 L/min
What are the 3 components of stroke volume? - CORRECT ANSWER -Preload
-Afterload
-Contractility
MAP goal - CORRECT ANSWER 65 mmHg
Tachycardia r/t Cardiac Output
& Dopamine example - CORRECT ANSWER Tachycardia leads to increased O2 consumption and decreased O2 supply.
If pt on Dopamine, may have increased HR leading to increased O2 consumption, decreased O2 supply.
-May need to decrease or stop Dopamine if HR is increased & SBP < 90.
-HR may then decrease enough to allow BP to increase d/t decreased demands.
SVR
Definition - CORRECT ANSWER The resistance the lt ventricle must pump against to move blood through the systemic circulation.
-Ability to constrict or dilate based on whether there is a volume or container problem.
SVR
Formula - CORRECT ANSWER [MAP-CVP]/CO x 80
SVR
Normal Value - CORRECT ANSWER 800-1200 dynes/sec
Causes of increased SVR - CORRECT ANSWER -Hypovolemic shock
-Vasoconstriction
-Lt ventricular dysfunction
Causes of decreased SVR - CORRECT ANSWER -Sepsis
-Neurogenic Shock
-Anaphylaxis
PR Interval Duration - CORRECT ANSWER 0.12-0.20 seconds
QRS Duration - CORRECT ANSWER 0.04-0.12 seconds
Normal Q wave width - CORRECT ANSWER =< 0.04 sec or 1 mm
Normal Q wave depth - CORRECT ANSWER =< 2 mm
Normal Q wave/R wave ratio - CORRECT ANSWER =< 25%
Pathologic Q wave width - CORRECT ANSWER > 0.04 sec or > 1mm
Pathologic Q wave depth - CORRECT ANSWER >2mm
Pathologic Q wave/R wave ratio - CORRECT ANSWER >25%
Placement of Precordial Leads - CORRECT ANSWER V1 - rt sternal border, 4th ICS
V2 - lt sternal border, 4th ICS
V3 - between V2 & V4, apply after V4 to get correct placement.
V4 - mid clavicular, 5th ICS
V5 - along armpit
V6 - midaxillary line
Cardiac Ischemia Definition - CORRECT ANSWER -Lack of O2, insufficiency
-ST depr or T wave inversion
Cardiac Injury Definition - CORRECT ANSWER -Prolonged ischemia
-ST elevation
Cardiac Infarct Definition - CORRECT ANSWER -Death of tissue
-May have Q waves
Pathologic Q Wave Definition - CORRECT ANSWER Complete transmural death of cardiac muscle in that specific area.
Indicates prior MI with no reperfusion.
What areas of the heart does the RCA supply? - CORRECT ANSWER For 90% of the population:
-SA node
-AV node
-Rt ventricle
-Branches out & supplies inferior & post wall.
Left main coronary artery circulation - CORRECT ANSWER Immediately bifurcates to the circumflex & LAD.
What areas of the heart does the circumflex artery supply? - CORRECT ANSWER -High lateral wall - Leads I & aVL
-Marginal arteries - lower lateral wall & possibly posterior part of heart.
What areas of the heart does the LAD supply? - CORRECT ANSWER -Anterior wall of lt ventricle
-Anterior septum
In 10% of the population, what coronary artery is dominate? - CORRECT ANSWER Left main
-Circumflex continues around & feeds inferior & post wall.
--II, III, aVF; V5, V6 will all be elevated in lt main dominate person with MI involving circumflex lesion.
Evolution of MI
Hyperacute Phase - CORRECT ANSWER -Early changes suggestive of MI
-Tall, peaked T waves
-May precede clinical sx.
-Only seen in leads looking at infarction area.
-Not used as diagnostic finding. But, should raise red flag.
Evolution of MI
Acute Phase - CORRECT ANSWER -ST segment elevation
-Implies myocardial injury is occurring.
EKG Interpretation - Anterior Leads - CORRECT ANSWER V1
V2
V3
V4
EKG Interpretation - Inferior Leads - CORRECT ANSWER II
III
aVF
EKG Interpretation - Lateral Leads - CORRECT ANSWER I
aVL
V5
V6
EKG Interpretation
Which group of leads are reciprocal? - CORRECT ANSWER I & aVL and II, III, aVF
III & aVL mirror each other.
Ex. If aVL w/elevation, III should have depression. This is diagnostic d/t reciprocal changes.
EKG Interpretation
Where may you see reciprocal changes with posterior wall involvement? - CORRECT ANSWER V1, V2, V3 may have ST depr when II, III & aVF have elevation.
What is the most common cause of a new systolic murmur with a recent inferior MI? - CORRECT ANSWER Mitral regurgitation d/t papillary muscle rupture that is most commonly associated with an inferior MI.
Is aortic stenosis a systolic or diastolic murmur? - CORRECT ANSWER Systolic
Is pulmonary regurgitation a systolic or diastolic murmur? - CORRECT ANSWER Diastolic
Is mitral stenosis a systolic or diastolic murmur? - CORRECT ANSWER Diastolic
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