Critical Care: test 3: Hemodynamics, MV, Respiration, basic ACLS Flashcards
What is the most common symptom of MI in women?
Unusual Fatigue
What’s the fastest Anti-Hypertensive on the market and the DOC for Hypertensive crisis?
Nipride (Nitroprusside)
Normal PA systolic pressure? PA diastolic?
20-30; 8-15
How often do you “Zero” your PA transducer?
Do at beginning of shift minimum; can do it before every reading if you really want to.
What type of meds do you give in an Art-line?
You should never give meds via an arterial line because of potential harmful complications!
The physical movement of air = ______
Ventilation
For someone with a bad TBI/drug-induced coma, we would want their SVO2 to be _____
Up. We don’t want them in a hypermetabolic state.
What is the action of Cardene (Nicardipine HCl)?
Vasodilation & Smooth Muscle Relaxation
Which 2 wave forms of the PA cath monitor look similar? How are they different?
The Pulm. Art. Wedge (PAWP or PCWP) looks similar to the Right atrial, but is usually higher. [
Most common cause of Resp. Acidosis?
Hypoventilation
What is the max amount of gas that can be inspired at the end of a normal breath, and what is the normal value?
IRV (Inspiratory Reserve Volume); 3000; This is what is measured with an Incentive Spirometer
When is Pressure Ventilation used?
It’s not as common as Volume Ventilation; it is used when a patient has stiff lungs (ie with ARDS)
Diagnostic Tests for CAD: (4):
12-lead EKG
CXR
Echocardiogram & Multigated Blood Pool Study (MUGA): focus on ejection fraction (<45% is not good)
TEE (transesophageal echocardiogram)
Reasons for Apnea Alarm to go off on Vent? Treatment?
Alarms when a breath is not taken in a certain amount of time= Patient is Apneic (due to medical issue, disconnect, over-sedation)
Life-saver in CPAP mode
Wake them up, Relieve sedation
Call RT and have them put back to their previous settings, if available.
What is the pressure bag connected to a PA catheter always blown up to?
300 mmHg
What drug is often given after a stent placement?
Plavix (anti-platelet).
What side of the heart is most affected with physiological issues?
Left side most commonly involved except for trauma
What is the difference between the alveolar and arterial partial pressure called? What value should it be less than?
A-a Gradient; 20 (greater than 20=hypoxia)
What are the two most dangerous timing errors of an IABP?
Too early Inflation = will block flow => increases pressure to push against = inc. workload/O2 demand; won’t allow emptying
Too late Deflation= Most dangerous; can cause fatality; won’t allow Ventricle to contract which can cause rupture of vent.
4 complications of an Art-line:
Thrombosis
Air emboli
Exsanguination
Infection
pH=7.31
PaCO2=30
HCO3=20
Partially compensated Metabolic Acidosis
When inadequate VENTILATION occurs, the lower airways have nothing to perfuse = ______
Shunt unit
What do you need to watch for after the femoral artery is punctured to do a PTCA (heart cath)?
Have to put pressure on artery (usually femoral) for up to 20-30 mins
Watch for aneurysm formation (will feel like disc under skin; try to smooth it out)
Watch for hematoma and pseudo-hematoma: will sound like a bruit; bad
Do distal circ checks
In Critical care, you want to ______ nursing care, unlike Med-surg.
spread out
Nipride (nitroprusside) is a potent ______
vasodilator
Who is more likely to survive an MI (what ages)?
Actually, the older you get, the more likely to survive because as you age you create more collateral circulation. So you’re more likely to survive an MI at 80 than at 50!
Positive Inotropics increase ____ which increases ___,___, & ____. What are 4 examples?
Intracellular Ca++; Inc. Myocardial contraction; Increases CO; Inc. Renal perfusion; Mid-level Dopamine (2-10), Dobutrex, Levophed (Norep), Digoxin
Type of Ventilator mode where vent automatically raises and lowers pressures to maintain a certain Tidal Volume =
PRVC (Pressure Regulated Volume Control)
The amount of blood the heart pumps out of a ventricle with each beat =
Stroke Volume (SV)
An IABP has helium inflate the balloon during ____ and deflates it during ______
Diastole (when heart is resting it’s inflated so blood doesn’t back-track); Systole (contracting so you want blood to be able to pass)
Right-sided heart issues usually involve volume _____ (with what exception)?
deficits. Except left-sided HF where volume overload occurs (most common cause of right-sided HF).
What do you do with Right Mainstem intubation (ET moves into right stem bronchus)? How do you determine this?
Common; won’t hear breath sounds on left side; Will have to pull back on ET until you hear them on both sides.
Treatments for ARF & COPD:
O2 Bronchodilators Corticosteroids Antibiotics Preventative Issues (flu/pneumonia vaccine)
You can think of an IABP (Intra-Aortic Balloon Pump) as a ________
Left Ventricular Assist Device (but you don’t go home with these)
If the Oxyhemoglobin Dissociation Curve shifts to the Left, it means there’s a(n) ___ affinity of O2 and Hgb. What are 3 things that could cause this?
Increased; coLd, aLkaLosis, Low CO2
What does the Distal lumen measure when the balloon is inflated?
PCWP (Pulmonary Capillary Wedge Pressure), aka “Wedge Pressure”; Measures indirect pressures in the left ventricle.
What can cause Air Trapping with a vent? How would you fix this?
Can happen if patient is fighting the vent; if RR set too high (COPD/emphysema at risk)
RT needs to make sure patient has adequate time for exhalation
Can sedate patients who are fighting the vent.
Which type of ventilation mode delivers a set # of breaths of a set Vt, and between these mandatory breaths, the patient may initiate spontaneous breaths?
SIMV
Normal RV systolic pressure? RV diastolic?
20-30; 0-5
S/s of ARDS Development:
- High pressure alarms going off on ventilator and you can’t find a mechanical reason why
- Increased HR
- Increased RR
- “Stiff Lungs”–
- Inc. pressure alarms going off
- Tachycardia and tachypnea that don’t follow the full picture; “Something seems wrong”
- Dyspnea
- Rapid, shallow breaths with accessory muscle use
- Abnormal breath sounds
- Mottling or cyanosis of the skin
- Dry cough
- Change in LOC
- Restlessness
- Retro-sternal discomfort
- Fever
Treatment of Left-sided heart problems =
Med therapy
Invasive therapy (IABP or assistive device)
May or may not require pacing.
Pulsus paradoxus can occur with which patients? What does this mean?
Cardiac tamponade: constriction of heart
Constrictive pericarditis
Pulm. HTN
Hypovolemia
Tension Pneumothorax
*Can mean that they are decompensating and/or there’s constriction on the heart
Risk Factors for Respiratory Failure: (7)
Aged Obesity Surgical Patients Smoking Imminent Surgery Trauma Patients Drug Abusers
What is the treatment for a right-sided MI?
Fluid replacement
Pressure left in the alveoli upon the end of expiration =? Allows ease in opening the alveoli upon the next inspiration; improves ability for gas exchange; decreases workload of lungs
PEEP (Positive End Expiratory Pressure)
Chemoreceptors respond to ___ changes like what? (4). Baroreceptors respond to ____ like ______
chemical; Inc. CO2, Dec. pH, Inc. H+, Dec. O2 (carotid and aortic bodies); Stretch of BV’s; If BP increases, leads to decreased HR; If BP decreases, leads to Increased HR
What is a normal P/F Ratio?
400-500 mmHg
Things that Increase Afterload (PVR and/or SVR): (6):
Hypervolemia Vasoconstriction Systemic HTN Pulmonary HTN (PPH) Dissecting Aortic Aneurysm Increased Blood Viscosity
An abnormal fall of SBP greater than 10 mmHg during INSPIRATION=? What do you do if you suspect this?
Pulsus Paradoxus;
1) Observe fluctuations on art-line
2) Manually obtain pressure
a) inflate BP cuff 20 mmHg above SBP
b) Slowly deflate, listening for Korotkoff sounds to appear during expiration
c) Continue to slowly deflate until sounds heard on both inspiration and expiration
d) Normal findings = less than 10 point difference
What are some shorter-acting sedation meds that can be used/may be preferred in ARDS treatment?
Precedex
Propofol
Possibly Versed (but lasts longer than the above two)
ARDS Treatment:
- Mechanical Ventilation
- Expect PEEP of about 15-20
- Expect Pressure Support as opposed to volume support ventilation
- Meds:
- Anti-inflammatory: ie steroids
- Vasodilator meds
- Surfactant therapy (not as common; controversial)
- Beta-agonist meds for bronchodilation
- Other “Investigational” therapies:
- Nitric oxide
- Liquid Ventilation
- ECMO: heart/lung bypass
- Surfactant therapy
Reasons for the Low Exhaled Volume Alarm to go off? Treatments?
Patient is disconnected from the vent (re-attach them) Loose tubing (tighten the tubing) Machine Malfunction (silence the alarm, remove from vent, bag the patient with O2 turned as high as possible, and call RT STAT)
Lung Compliance measures _____; ___ compliance means they stretch but they don’t want to recoil (ie with ____); _____ compliance means they are very stiff and have a decreased ability to stretch (ie with __,__,&___).
How stiff the lungs are; Increased; COPD; Decreased; ARDS, Pulm Fibrosis, Interstitial Fibrosis
What do you do with the syringe after you get a Wedge Pressure (PCWP)?
After you do the wedge, pull the syringe off, depress it, then reattach it. DO NOT LEAVE THE SYRINGE WITH THE PLUNGER PULLED BACK!
Preload aka ___ & ___; it predicts ____
CVP; RAP; CO
pH=7.47
PaCO2=48
HCO3=30
Partially compensated Metabolic Alkalosis. It’s only partially compensated because the pH didn’t return to normal (which would have made it fully), and it’s compensated because the CO2 was high like the HCO3
Mid-level Dopamine (2-10) mostly stimulates ___ which does what?
Beta 1; stimulation results in increased HR, Contractility, Conduction (Pos. Inotropic & Chronotropic)
Alarm that goes off when something is not allowing the volume to flow into the lungs as usual; resistance being met =
High pressure alarm.
A person in a hypermetabolic state (ie Trauma, burn, shock) would have an SVO2 that would be ___ than normal.
lower because the body is trying to heal itself. For example, in a normal person, a reading of 70% means that the body is using 30% of O2. Therefore, a person in the example, may have a low SVO2 (like say 30%) because the body is using 70% O2 to try to heal itself. If they didn’t have a low SVO2 then we may be worried that the body has given up. Mixed venous oxygen saturation (SvO2) is the percentage of oxygen bound to hemoglobin in blood returning to the right side of the heart. This refects the amount of oxygen “left over” after the tissues remove what they need
_____ is how saturated the Hgb is with O2 at the end of the circulation pathway.
SVO2 (systemic venous O2); can see how much O2 the patient has used (compare it to an ABG from earlier).
How is an IABP inserted?
A 30-40 mL balloon introduced through the femoral artery into thoracic aorta; connected to bedside console; it should stay below the L.subclavian and above the renal arteries
The distal port of the PA catheter is found where and measures what?
is in the pulmonary art; measures PAP and PAOP; this is where the readings take place; gives waveform and #
Too Early Deflation of an IABP will cause what?
It won’t allow it to “suck”/assist = It’s like the device doesn’t exist
Normal CVP/RAP?
2-6 mmHg
What is the wave form you want to see on the PA cath monitor every time you walk into the room?
The pulmonary artery one that has the dichrotic notch. Normal PA systolic is 20-30 mmHg and PA diastolic is 8-15 mmHg
pH=7.33
PaCO2=50
HCO3=30
Partially compensated Respiratory Acidosis.
Normal SV =
60-100 mL/beat
pH=7.31
PaCO2=50
HCO3=22
Resp. Acid.
How, why, and where is a PA catheter inserted?
Inserted under sterile conditions, usually in the diagnostic lab (ie cath lab), however, can be inserted at bedside usually with fluoroscopy (can go blindly, though), or in surgery. It is inserted in the internal jugular, subclavian vein, or can be brachial or femoral if needed. You have to confirm placement with an x-ray. The purposes are to measure pressures of the heart (via the PA-Pulm. Art)–Continuous CO (CCO), continuous Right ventricular end diastolic volume (RVEDV), Right Ventricular Ejection Fraction (RVEF), and continuous mixed venous oxygen saturation SvO2….etc… They can also measure core body temp, give large amounts of fluids thru them, and specialized ones can also pace.
pH=7.52
pCO2=18
HCO3=24
Uncompensated Resp. Alk
Common causes of Resp. Acidosis?
(Retention of CO2)
Hypoventilation CNS depression (drugs, drug overdose, anesthesia) Resp. Neuromuscular Disorders Trauma: spine, brain, chest wall Restrictive Lung Diseases COPD Acute Airway Obstruction (late phases)
Type of Respiratory Failure with decreased ventilation = _____; Some causes?
Hypoxemic Hypercapneic Failure (Type 2); Musculoskeletal and/or Neurologic system failure, MD, ALS, Guillain-Barre, Skeletal deformities like scoliosis, kyphosis
What is a typical tidal volume/pressure for the vent?
10-15 mL/kg (ARDSnet recommends 4-8 as lung protective strategy).
What test do you have to do before insertion of an art-line in the radial artery? How do you do it?
Allen Test–assesses the patency of the ulnar artery; To do it–
1) Patient forms tight fist with wrist in neutral position
2) Occlude both radial and ulnar arteries for approx. 10 seconds
3) Patient opens hand to reveal blanched hand
4) Release pressure on ulnar artery (pinky side) while maintaing pressure on radial side
5) Ulnar circulation is adequate if blanching resolves within 5 secs; inadequate if >10 seconds
Things that decrease Cardiac Output (CO): (9):
Hypovolemia Hemorrhage HF AMI Right-sided HF/AMI Third-spacing/pooling Arterial blood clot/DVT Tachycardia/Bradycardia Cardiac Tamponade
Name 4 drugs to increase afterload:
Epi, High dose dopamine, Norep (Levophed), Neosynephrine —vasoconstrict
What is the half-life of Corlopam?
5 min
Vascular resistance to the forward flow of blood leaving the right & left ventricles =
Afterload (SVR): aka the amt of pressure the left side has to work against. aka The resistance to the flow of blood from the heart.
The ____ usually dictates Cardiac Output.
Preload
Name 3 drugs to reduce preload & afterload:
Nipride, Nitroglycerin, & Diuretics
Which heart valves are anchored by chordae tendineae?
AV valves
Causes of Respiratory Alkalosis:
(Hyperventilation)
Hypoxemia
Anxiety, fear
Pain
Fever
Stimulants
CNS Irritation (e.g. Central Hyperventilation)
Excessive Ventilatory Support (bag-valve mask, mech. ventilation)
What is a typical Rate for the ventilator?
8-12 is typical for adults (slower for COPD and higher for non-compliant lungs)
What happens if the balloon breaks while you are trying to obtain a PCWP (“Wedge Pressure”)?
Don’t have to remove catheter, but won’t be able to obtain PCWP’s anymore. Will have to replace if needed, or have to tape off and put up sign not to use. Risk of air emboli.
What are some adequate ABG measurements before Respiratory Failure occurs?
pH=greater than 7.25
PCO2= less than 50
PaO2= greater than 50
*loose definition of what they should be. Depends on patient.
Things that decrease Afterload (PVR and/or SVR): (4):
Hypovolemia
Vasodilation
Sepsis
Hypotension
How much blood is coming off the left ventricle in a minute =
CO (Cardiac Output)
What treatment is used for Stridor upon extubation?
Racemic Epi (aerosolized) for Mild Stridor; Reintubate for Moderate Stridor
Which type of ventilation avoids Intubation/Tracheotomy and closely mimics normal breathing?
Negative Pressure Ventilators
Most common cause of Met. Alkalosis?
Vomiting.
What is the amount of air remaining in the lungs after maximum expiration (amount that keeps the lungs open), and what is the normal value?
Residual Volume (RV); 1300
What do you do with Barotrauma?
Keep pressure at minimum, if possible. This will mean less perfusion which may cause bad ABG’s (hypercapnia, etc) which you may just have to deal with. Barotrauma can cause a tension Pneumo.
___ or ___ is used to measure Preload.
RAP (Right Atrial Pressure) or CVP (Central Venous Pressure)
Which side of heart problems may recover spontaneously and which side often reuqires assistance?
Right may recover spontaneously; Left often needs assistance.
What is a typical Pressure Support setting for the ventilator?
Complete support: around 15-20
As boost with SIMV or CPAP: 5-15
*anywhere from 5-20
How do you prevent Oxygen Toxicity from the vent (damage to the lung due to high O2 levels)?
Use lowest O2 available, if patient desats–dont forget to wean O2 when they recover.
The extent of damage of an AMI depends on what? (6)
Amount of damage Area of damage Pre-existing illnesses Time to initiation of healthcare Time to tx upon this initiation Presence of collateral circulation
What do you want to watch for with an IABP to make sure it hasn’t moved and why?
It’s supposed to be below the L. Subclavian and above the renal arteries. Therefore, WATCH Urinary Output (if blocking perfusion to renal arteries, then UO can change), and watch Circulation to left arm (to make sure it hasn’t moved up to block arm; watch left leg circ too).
What does a low SVR mean?
The left side of the heart isn’t working against a lot of pressure; they probably also have a low BP
What do you do if you are even in doubt of the functioning of a ventilator?
Take them off and bag them! And call respiratory therapy.
What’s a V/Q Mismatch?
A ventilation or perfusion problem.
pH=7.36
paCO2=50
HCO3=29
Fully compensated Respiratory Acidosis. The pH is within normal limits, therefore complete compensation has occurred.
5 factors affecting afterload:
- Vasoconstriction–SVR goes up
- Atherosclerosis (CHD)–SVR goes up
- Obstructions–SVR goes up
- Medications (that vasodilate or constrict)
- Shock (depends on type–vasodilate or constrict)
pH=7.33
PaCO2=40
HCO3=21
Metabolic Acidosis. It isn’t compensated because the CO2 didn’t try to compensate, and the pH didn’t return to normal.
Measures indirect pressure in the left ventricle =
PCWP
What is the drive to breathe for a normal person? For a COPD patient?
High CO2; Low O2
Which type of Ventilation ensures that the patient receives adequate ventilation, regardless of spontaneous efforts? (ie Patient emerging from general anesthesia or with pulmonary disease such as Pneumonia)
A/C Ventilation (aka CMV)
The percentage of oxygen bound to hemoglobin in blood returning to the right side of the heart; Mixed venous O2 Saturation; This refects the amount of oxygen “left over” after the tissues remove what they need =
SVO2
PSNS: \_\_HR (\_\_ chronotropic) \_\_Gastric secretion (Motility) \_\_Bladder/Bowel Emptying Miosis or Mydriasis? Bronchial smooth muscle \_\_\_\_\_\_
Decreased HR (neg Chronotropic) Increased Gastric Secretion (motility) Increased Bladder/bowel emptying Miosis Bronchial Constriction
What is a normal FiO2 setting on the ventilator?
it’s set from 0.21 (21% or room air) to 1.00 (100% Oxygen); it’s based on the patient’s needs and should be set to maintain a PaO2 between 60-100 and/or SpO2 of at least 90%. After stabilized, the setting is adjusted based on ABG or pulse ox values. It’s weaned by 5-10%….. If in doubt, always use 100%.
The THIN black lines on a PA catheter are ___ and the thick one is ____
Thin = 10 cm; thick = 50 cm
What are some fixes for an occluded ET tube?
Adequate hydration
Position changes
Suction as needed
*These all prevent mucous plugs which are common cause; will cause high pressure alarm; suction plug or may have to change position; careful with giving NS (only small amt); If suction doesn’t work, take off vent and bag them (pushes mucous plug down); you will hear a “pop” when the plug goes down and this isn’t a bad thing, but you should not feel resistance.
When the lower airways are not PERFUSING, it’s called _________
“Dead space unit”
What is a “Square Wave Test”?
It is used to verify that the transducer system of the PA catheter can accurately represent cardiovascular pressures. It is done by recording the pressure waveform while activating the fast flush valve/actuator on the pressure tubing system for at least 1 second. The resulting graph should depict a rapid upstroke from the baseline with a plateau before returning to baseline (ie Square wave). Upon return of the pressure tracing to baseline, a small undershoot should occur below the baseline, along with 2 oscillations, within 0.12 seconds before resuming the pressure waveform.
If it meets this criteria, the system is optimally damped, and resulting waveforms can be interpreted as accurate. If it is overdamped (no oscillations, upstroke is slurred, or small undershoot is not produced, it can result in a systolic pressure that is falsely low & diastolic falsely elevated.
Typical causes of ARF & PE:
DVT Fat globule from long-bone fracture Septic vegetation Iatrogenic catheter fragment Amniotic Fluid Emboli
If the Oxyhemoglobin Dissociation Curve shifts to the RIGHT, it means there’s a(n) ____ affinity of O2 on Hgb. What are 3 things that could cause this?
Decreased; feveR, Reduced pH, hypeRcapnia (way to remember–uppercase “R’“‘s for the shift to the “Right”)
What is the main issue with COPD?
Chronic Inflammation=chronic repairing of injured airway tissue=scarring/obstruction
What are some signs of Dig toxicity ? What do you most of the time if you suspect it? What is the antidote and another way to treat it?
Visual changes (blind spots, blurred, halos, etc), N/V/D, Loss of appetite, Cardiac Dysrhythmia; Most common way to fix= Hold dose, Call MD, let half-life occur, do blood draw, restart if possible; Digibind is antidote; Can give IV K+ (slowly!) (Dig and K+ compete for the same receptor sites so if you are hypokalemic, then Dig can go toxic quickly).
Normal PVR=
27-250 (150-300)
pH=7.32
PaCO2=50
HCO3=28
Partially compensated Respiratory Acidosis. The arterial blood gases are only partly compensated because the pH is not WNL.
What levels do you have to check with Nipride?
Cyanide levels
Lab tests for CAD: (5):
1) CPK (Creatinine Phosphokinase): Increases within 2-4 hours, peak at 18-36 hours, baseline return in 3-6 days
- CPK-MB (heart): Myocardial involvement
- CPK-MM (skeletal muscle): Trauma
- CPK-BB (brain)
2) Troponin 1 & T: more sensitive and useful for early detection of MI; elevate 1 hour
3) Myoglobin: for trauma to skeletal muscle; not specific to myocardial except a doubling is usually indicative of AMI (unless multiple skeletal muscle trauma is suspected)
- Released within 30-60 mins after muscular injury
- known to rise prior to CPK-MB
Normal SVO2?
60-80%
What is the purpose of an Intra-Aortic Balloon Pump (IABP)? What does it increase and decrease specifically?
Circulatory device that enhances the function of a compromised heart
Increases: Cor. Art Blood flow & perfusion (and thus myocardial O2 supply)
Decreases: Cardiac O2 demand (by assisting L.Vent) & Workload of L. Ventricle
When does Troponin elevate?
one hour.
3 Indications for an Arterial Line (art-line):
Hemodynamic instability/Constant BP & HR monitoring
Frequent ABG draws
Assess efficacy of vasoactive meds
What can a Vigileo (Flo-trac) measure?
CCO (Continuous CO) SV (Stroke Volume) SVV (Stroke Vol. Variation) DO2 (O2 delivery) ScvO2(Oxygen consumption)
Normal SVR =
800-1200
The amount of resistance the left side of the heart goes against to pump out =
Afterload (SVR)
What should you NEVER do when a patient is on CPAP?
Knock out their drive to breathe.
What would you do if you saw the Right Ventricle wave form appearing on the monitor of your PA cath?
Safest way to handle it is to pull back until you see the Right Atrial reading and call for someone experienced to re-advance it.
Causes of Metabolic Alkalosis:
(Gain of Base)
Excess ingestion of antacids
Excess administration of sodium bicarbonate
Citrate in blood transfusions
(Loss of Metabolic Acids) Vomiting Nasogastric Suctioning Low K+ and/or Chloride Diuretics (loss of Chloride and/or K+)
Afterload aka ___
SVR (systemic vascular resistance)
Which side of the heart usually leads to significant and faster onset of CO deficits? Which side may be the primary cause of CO deficits yet onset may be slower?
Left; right
Which valves are usually more affected by stenosis?
Semilunar
Prevention of ARDS:
- Wash hands (sepsis prevention)
- HOB at 30-45; some studies show that Prone position can be used/use Rotoprone Bed
- Oral Care
- IV Care
- All recommendations to reduce ventilated assisted pneumonia
Go over a picture of the wave forms with insertion of PA cath….
.
Doses of Carlopam should be low to minimize ________
reflex tachycardia
Which mode of ventilation is positive pressure applied throughout the respiratory cycle to a spontaneously breathing patient?
CPAP (Continuous Positive Airway Pressure)
What is the relationship between PaO2 & FiO2 called?
P/F Ratio
What is Starling’s Law?
In medical science, the term Starling’s Law refers to a theory, which states that “the greater amount of blood volume (preload) into the ventrical of the heart during diastole (the relaxed phase) the greater the amount of blood volume ejected out of the heart during the systolic(contraction phase).”
(The more you stretch the chamber, the greater the “snap-back”)
What is the maximum volume of gas that can be forcefully expired after maximum inspiration, and what is the normal value?
Vital Capacity (includes Tidal Volume, IRV, and ERV); 4700
What are some direct injury causes of ARDS? Indirect injury causes?
Direct: Aspiration Burn Exposure to chemical substance Trauma Indirect: Sepsis: most common indirect cause Cirrhosis Alcoholism
The amount of blood in the ventricle at the end of diastole =
Preload
How many mL’s can the balloon on the PA catheter hold?!
1.5 mL
Normal CO =
4-6 L/min
3 major assessment for IABP:
Left arm assessment
Left leg assessment
Kidney assessment
A minimum of ___ mL should be connected to the PA cath line as well.
3 mL
What are some ways to prevent VAP (Ventilator-Associated Pneumonia)?
Use of “Ventilator Bundle”:
- HOB 20-45 (most prefer greater than 30, unless otherwise contraindicated)
- Daily “Sedation Vacations”: take off meds to check for arousal of breathing/readiness for extubation
- Peptic Ulcer prophylaxis (Proton-pump Inhibitor meds)–prevent aspiration of gastric acid
- DVT prophylaxis (change positions, ROM, etc)
- Antibiotic/Antifungal topical degerming agent have been suggested
Therapeutic Dig level =
0.8-2.0
AMI is simply an imbalance between __ &___
myocardial O2 demand and supply.
What does the waveform look like for an Art-line?
Has a dichrotic notch; Looks like Pulm. art pressure except taller
The ___ valves open during ventricular diastole. As the ventricles contract in systole, the ___ valves close and the ____ valves open.
AV (tricuspid & bicuspid/mitral); AV; Semilunar (aortic & pulmonic).
CPK increases at ____ hours, peaks at ____ and returns to baseline at _____
2-4 hours; 18-36 hours; 3-6 days
When you measure the CO via the TdCO method (using a temperature change measure), a higher temp means ___ Cardiac Output while a lower temp means ___ C.O.
less; better
Where is the proximal port located in a PA catheter and what does it measure?
in the right atrium; measure RAP (CVP) and preload, this dictates Cardiac Output (CO).
Diagnosis of ARF & PE? (3)
- Pulmonary Angiogram (GOLD STANDARD): direct visualization of pulm. vasculature
- D-Dimer (sensitive but not specific)
- V/Q Scan (may assess dead space created by PE)
What’s a VQ Ratio?
The rate of Ventilation (V)(physical movement of air) and the rate of perfusion (Q)(diffusion of O2 & CO2 between the alveoli & pulm. capillaries). V usually equals Q resulting in a ratio of 1.0.
Which mode of mechanical ventilation is used for spontaneously breathing patients and for weaning?
SIMV
What should the HOB be at when someone has a PA cath?
Anywhere from 0-45 degrees, but make sure it’s the same at every reading.
Nitroglycerin is a vaso_____.
vasodilator, primarily venous
pH=7.35
PaCO2=34
HCO3=20
Fully compensated Metabolic Acidosis.
Neosynephrine is a strong ___ receptor stimulator which causes _____
alpha 1; vasoconstriction; used for severe hypotension, often after heart surgery
SVO2 monitoring is affected by 4 variables :
C.O.
Hemoglobin (healthy? something displacing it?)
Arterial O2 saturation
Tissue O2 consumption
Pressure support is only used for which modes of Mechanical Ventilation?
SIMV & CPAP because there have to be spontaneous breaths
Type of ventilation where a set amount of breaths are delivered with each one receiving a set amount of volume or pressure (depending on if we are using volume control or pressure control); Each of the mechanical breaths give a set amount; If patient is breathing on their own, the patients starts their breath then the machine takes over & makes sure that breath is to the setting required.
A/C (Assist Control) Ventilation
What is the main difference between the SIMV and the A/C modes of the ventilator?
Main diff is the volume of the patient-initiated breaths. Patient-initiated breaths in A/C still result in a patient receiving a set Vt. In SIMV, the Vt of spontaneous breaths is variable because it depends on patient effort and lung characteristics.
Most common cause of Resp. Alkalosis?
Hyperventilation.
What is the max amount of gas that can be forcefully expired at the end of a normal breath, and what is the normal value?
ERV (Expiratory Reserve Volume); 1200
Criteria for diagnosis of ARDS: (4)
- Acute onset within one week of insult
- Bilateral pulmonary opacities not explainable by other means (“white-out” on x-ray)
- PEEP > or equal to 5 cm H2O
- PaO2/FiO2 Ratio: Mild=201-300; Mod=101-200; Severe=< or equal to 100
What patients are listed as benefiting from less invasive hemodynamic montoring? (5)
1) Predominantly non-cardiac surgical patients (ortho, general, thoracic, vascular)
2) Predisposed to increased risk of complications, comorbidities (HF, cardiomyopathy, COPD & RF), Advanced Age
3) Hx of CAD
4) Risk of fluid shifts (Complex GI cases)
5) High risk of blood loss (trauma, hip revision, complex vascular, etc).
pH=7.31
PaCO2=44
HCO3=20
Metabolic Acidosis.
Myocardial cells can endure hypoxia for about _____ mins before irreversible damage occurs.
20 mins
How is the CO calculated? The CI (Cardiac Index)?
CO= HR x SV (PA cath gives this); CI= CO/BSA (Body surface area–calculated by height and weight); These both have the same meaning (except CI may be more specific to patient), but they have the same meaning!! They have different normal value reference numbers, though.
What are the weaning parameters on the ventilator?
Adequate oxygenation on minimal FiO2 (typically 40% or less)
VC >10-15 mL/kg
MIP (NIF) lower than -20
Rapid shallow breathing index (RR/VT) <100
Common cause of Met. Acidosis?
Diarrhea.
Which type(s) of Angina have pain at rest?
Unstable & Variant (Prinzmetal’s/Vasospasmic)
What is PTCA (heart catheterization) used for? (3)
Viewing coronary arts
Placing stents
Displacing plaque and blockages (ie from CAD)
pH=7.48
PaCO2=45
HCO3=30
Metabolic Alkalosis. It’s not compensated because CO2 didn’t try to compensate (go out of normal range in the same direction), and the pH didn’t return to normal.
What is the most common reason for the insertion of an IABP?
Cardiogenic shock
What does the Oxyhemoglobin Dissociation Curve represent?
The relationship between PaO2 and the SaO2 is shown; Represents the Affinity of O2 to Hgb
How is a right-sided MI treated?
With fluids (and then eventually diuresis); may have to have pacing.
What is CPAP Ventilation Mode used for?
Non-invasively for obstructive sleep apnea
In Neonatal ICU to treat Resp. Distress Syndrome
Adult ICU, used for weaning.
How is “Vigileo” different from a “Swan-Ganz” or “Swan” PA catheter?
Easy to Use and Less Invasive
• Provides the same utility as continuous SvO2 monitoring from a Swan-Ganz catheter but on a central line/Art-line
• Requires no additional catheters, boluses or chemical indicators
What does the thermistor port of a PA catheter do?
Measures real time core body temp with sensors located distally.
Reasons for Mechanical Ventilation: (5)
- Resp. Failure
- When paralytic agents are used
- Surgical Support
- Respiratory Rest
- To restore physiological stability
4 Indications for a Pulmonary Artery Catheter:
Assess SvO2
Directly measure CO
Identify/treat cause of hemodynamic instability
Assess PA pressures
Dobutamine (Dobutrex) is used for what?
Pump problems (HF, Pulm. Congestion) with SBP of 70-100 and no signs of shock
The diffusion of O2 and CO2 between the alveoli & pulmonary capillaries =
Respiration/Perfusion/Oxygenation
What is a normal lung Compliance?
100 mL/cm
What solution is recommended for the flush system?
0.9% normal saline; it is placed in the pressure bag that is inflated
SNS: \_\_ HR (\_\_ Chronotropic) \_\_BP (vaso\_\_\_\_\_) Bronchial \_\_\_\_\_ \_\_\_ of blood=vaso\_\_\_\_\_\_ Miosis or Mydriasis? \_\_\_ glucose to brain & fatty acids to muscles
Increased HR (pos. chronotropic) Inc. BP (vasoconstriction) Bronchial dilation Shunting of blood (vasoconstriction) Mydriasis (increased field of vision. However, decreased ability to see fine detail--why people at crime scene don't remember details well Increased glucose & fatty acids
Dobutrex stimulates ____ receptors which causes what?
Beta 1; pos inotropic and pos chronotropic (Increased HR & Contractility)
Treatment for ACS: (7)
- Pain relief: Morphine (dilates coronary arts and pain relief); Can use NTG if SBP greater than 90
- O2 (want greater than 90%)
- Rest (improves o2 supply/demand)
- Anti-dysrhythmics
- Platelet aggregation prevention
- Thrombolytic Therapy
- PTCA (usually 60-90 mins door to balloon time)
- BB’s: thought to be cardio-protective (dec HR/BP/O2 demand)
Indications for an IABP (7):
Pre and/or post CABG surgery Cardiogenic shock---Most common reason L. Vent Failure Unstable Angina Refractory Dysrhythmias Septic Shock Bridge to Heart Transplantation--2nd most common
Complications of ACS:
Cardiac Dysrhythmias HF Thromboembolism Rupture of Heart structures Pericarditis Infarct extension AMI re-occurance Cardiogenic Shock
The PA catheter can measure: (7):
- Preload/CVP
- Afterload/SVR (systemic vascular resistance)
- CO (Cardiac Output)
- CI (Cardiac Index–same as CO, except has body surface area calculated in)
- PCWP (pulm. cap. wedge pressure)
- Core Temperature
- Indirect LV pressure
6 Indications for a CVC (Central Venous Catheter):
Administer large-volume fluid resuscitation or irritant meds
Access to place transvenous pacemaker
Assess SCVO2 (Central Venous O2 Saturation)
Measure R. Heart filling pressures
Estimate fluid status
Guide Volume Resuscitation
Which side of the heart is usually affected with front-collision trauma?
Right.
What are the 3 levels of Dopamine used for?
LOW DOSE: 0.5mcg-2mcg; Stimulates dopaminergic receptors in kidneys causing vasodilation=inc. circ & U.O. (however, urine is not filtered in the same capacity so toxicity is possible). Don’t really use low-doses anymore.
MODERATE DOSAGE: 2-10 mcg; 2nd most common; Mostly Beta 1= Inc. Contractility/HR/CO
HIGH DOSAGE: >10mcg; MOST COMMON; Some Beta 1 until about 15 mcg, then strictly alpha 1 from that point on; Can be third line drug to increase BP.
When is Myoglobin released after muscular injury?
30-60 mins.
What is a classic signal of ARDS that can alert you that it may be occurring?
The high pressure alarm on the ventilator keeps going off and you can’t find anything mechanically wrong with it. Means lungs are getting stiff. May have to change settings to pressure control.
Epinephrine stimulates which receptors?
Alpha 1 & 2 (peripherally), Beta 1 & 2
Reasons/Treatment for High Pressure Alarm on Vent =
- Biting ET tube (put in bite block if needed)/Obstructed ET tube
- Mucous Plug (suction the patient)
- Coughing (re-position, meds or sedation)
- Pneumothorax (chest tube needed)
- ARDS (stiff lungs): usually one of first things you see with onset/worsening of ARDS
What are some risks of the PA cath on insertion and during maintenance?
- Infection
- Dysrhythmias
- Pneumothorax— will need chest tube
- Balloon rupture– will need to replace or tape off and put up sign not to use.
- air emboli
- Pulmonary Thromboembolism
- Exsanguination (excessive loss of blood)
- Pulm. Art. Infarct
Most MI’s are on the ____ side.
Left.
What do you see with a Tension Pneumothorax and how would you treat?
Trachea will shift toward GOOD side
Will have needle decompression with puncture site at 2nd ICS/above the rib with 14 gauge needle;
Follow up with Chest tube placement
Causes of Metabolic Acidosis:
(Increased Acids) DKA Renal Failure Lactic acidosis Drug overdose (salicylates, methanol, ethylene glycol)
(loss of base)
Diarrhea
Pancreatic or small bowel fluid loss
What location do you use to measure where you want the transducer for the PA catheter set-up?
Want transducer level with the “Phlebostatic Axis”, preferably on the right side. It’s level with the Right atria, midaxillary at about 4th/5th ICS.
Things that Increase Pre-load (CVP and/or PAWP): (4)
Vasoconstriction
Renal Involvement
HF
Cardiac Tamponade
What is the most common type of angina that is usually indicative of CAD and goes away with rest or meds?
Stable Angina
What is mod-level Dopamine (2-10) used for?
To increase HR/CO/Contractility; Symptomatic bradycardia after Atropine failure
Potential Complications of IABP: (4)
Hemorrhage
Infection
Thromboembolism
Mechanical complications (Balloon leak/rupture, Gas embolism, Aortic wall damage)
Levophed (norepinephrine) stimulates which receptors? What does this cause?
Alpha 1 (stimulation causes vasoconstriction=Inc. BP) & Alpha 2 (peripheral), & Beta 1 (which causes pos. Inotropic/chronotropic); similar to Epi, but does not activate Beta 2 (doesn’t affect glucose and isn’t used as rescue inhaler). Often 1st line to raise BP.
What side of the heart is the “workhorse” of the heart?
left
Name 2 drugs to decrease only afterload:
Corlopam (Fenoldopam mesylate) & Cardene (Nicardipine Hcl)
If the Oxyhemoglobin Dissociation Curve shifts ____, it makes it easier for the patient to become hypoxic.
Right.
Which two labs are most used for MI?
CPK-MB & Troponin; Troponin most sensitive and useful for early detection (elevate at 1 hour) (CPK-MB elevate at 2-4 hour and peak at 18-36)
Risk Factors for CAD:
- Gender/Age: men greater risk until women hit menopause and it’s equal. Women more likely to die with early onset CAD/AMI
- Heredity: Especially if diagnosed prior to 55 years and if death of family member occurred at early age.
- Smoking: Nicotine=vasoconstriction; increases LDL levels
- Physical Inactivity: most states recommend 30 min, 3x/week
- Blood Cholesterol: HDL=good; LDL=bad; VLDL=unknown but thought to have relationship to pancreatitis
- HTN: SBP &DBP less than 120/80
- Overweight
- Diabetes
Things that Increase Cardiac Output (5):
Increased O2 demand Hypotension Detected hypoxia Neurogenic mediated vasodilation Tachycardia
Which mode of Mechanical Ventilation provides an added measure of support with only spontaneous breaths? Often used in conjunction with SIMV or CPAP to help those breaths which are spontaneous; can be used alone, though
Pressure Support
What is surfactant?
An endogenous substance that allows alveoli to remain open in their bulbous form.
S/S of ARF & PE? Which are the 3 classic symptoms?
- 3 classic: Dyspnea, Hemoptysis, Chest Pain
- Unexplained cardiorespiratory complaints, specifically with those at risk (ie 80% have evidence of DVT)
- Sudden onset Dyspnea
- CP aggravated by deep inspiration
What is a normal PEEP?
5-20 (above 10 be careful). Everyone is on 5 to discount the loss due to residual loss from the ET tube. May be reduced if hemodynamic instability is noticed.
An IABP is timed off of which part of the EKG?
QRS
Which type of Angina is related to spasms of the coronary arteries and usually has EKG changes (ST seg elevation/depression)?
Variant (Prinzmetal’s/Vasospasmic)
What happens with an IABP if there’s Too Late Deflation?
This is the most dangerous. Can cause fatality. Won’t allow ventricle to contract so the ventricle could possibly rupture.
What is the volume of a normal breath called (amount breathed in and out), and what is the normal value?
Tidal Volume; average person is about 500
What is Corlopam (Fenoldopam mesylate) mainly used for?
HTN crisis
Treatment for ARF & PE: (4)
- Thrombolytic therapy (Streptokinase, alteplase - t-PA)
- Anticoagulation
- Catheter Embolectomy
- Vena Cava Filters
Normal PCWP (PAWP) =
4-12 mmHg
What is an important nursing consideration for when a patient gets a TEE done?
Must have gag reflex after before resuming normal diet.
What do you do if the PA cath gets stuck while doing a wedge?
Multiple options:
1) GENTLY tug
2) turn on left side (movement may dislodge)
3) have them bear down and cough
4) can suction them (which makes them cough)
How is Unstable Angina and Prinzmetal’s (Variant/Vasospastic) Angina Treated?
More aggressively: NTG, CCB’s (ie Procardia), etc.
Things that decrease Pre-load (CVP and/or PAWP): (5)
Hypovolemia Decrease in venous return to the heart Vasodilation Hypothermia Sepsis
What are some situations that can stress the resp. system and exacerbate ARF or COPD?
HF (especially CHF) Dehydration Electrolyte Imbalances Dysrhythmias Pulm. Edema Pneumonia
What is high-level Dopamine (>10mcg) used for?
Some beta 1 until around 15 mcg, then strictly alpha 1 = vasoconstriction = Increased BP
Which valves are most commonly involved in issues (ie infections)?
AV valves (Tri and Bi/Mitral)
Type of Resp. Failure that has decreased perfusion from alveoli to artery system =_____; Some causes?
Hypoxemic Failure (Type 1); Pneumonia (most common), Pulm. Edema, Aspiration, ARDS, Atelectasis.
What happens with an IABP when there’s too Late Inflation?
The blood has already passed so you lose the opportunity for blood to concentrate in the aortic arch. Therefore, it’s like the device doesn’t even exist.
Name 4 factors that affect preload:
Fluid volume–hypovolemia=decreased preload
Right sided MI–problem with return to heart/suction
Right sided HF–same as above
Atrial Dysrhythmias
Name some determinants/assessments of C.O. (Cardiac Output)?
HR
Preload (Starling’s Law)
Afterload
Contractility
When both ventilation and perfusion are impaired, it’s called a ________
Silent Unit
Left-sided heart issues usually involve ___ issues. Often leads to ________
pump issues (therefore decreased CO); engorgement of chambers & pulmonary involvement
pH=7.30
paCO2=50
HCO3=22
Resp. Acidosis (no compensation)
What happens in the Acute phase of ARDS? Late Phase?
Acute:
Systemic Inflammatory reaction secondary to direct or indirect injury/condition
Damage to alveolar/capillary membrane
Leakage of fluids, proteins, and blood cells into lungs ==> PE
Infection and Pneumonia Risk
Late: Fibroproliferation stage occurs over time (24-48 hours) Fibrin Matrix (hyalin membrane) forms (stiffens) = Dec. residual capacity, inflammation, narrowing of airway, Risk of atelectasis. -Treat with Pressure Ventilation
Which type of Ventilation do we normally use?
POSITIVE Pressure Ventilators (as opposed to Negative Ventilators which are rare; used with Iron Lung & Chest Cuirass); usually with VOLUME Ventilation–a Tidal Volume is set (as opposed to Pressure Ventilation where pressure is set at a fixed rate).
Digoxin is a ____. Its action increases ____ which Increases ___,___,&___. It also slows ___&____
Cardiac glycoside; increases intracellular Ca++; Increases myocardial contraction/CO/Renal perfusion; Slows cellular repolarization & conduction through AV node.
How is Stable Angina usually treated?
usually treated PRN
What happens with an IABP with Too Early Inflation?
Will cause backflow which increases pressure to push against; Increases workload and O2 demand; won’t allow emptying of contents
2 important nursing aspects of an Art-line:
Infection
Distal circ checks
Where does the distal end of the PA Catheter sit? The Proximal end?
in the Pulmonary Artery; Right atria
Normal CI =
2.5-4.5 L/min/m2
