Midterm Study Guide: Cardiac & ABGs Flashcards
two types of hypovolemic shock
Absolute and Relative
Absolute shock:
decreased preload from volume loss of circulating blood
Relative shock:
decreased preload d/t increase in the capacity of blood vessels to sequester blood volume away from the heart
four stages of schock
initial, compensatory, progressive, refractory
initial stage: what does this look like
*usually not clinically apparent
*metabolism changes at cellular level from aerobic (w/o2) to anaerobic (w/o o2) depriving the cells of oxygen
*causes lactic acid to build up and must be removed by the liver which requires o2, but o2 is unavailable d/t decreased tissue perfusion
Compensatory stage
During the compensatory stage of shock, the body tries to maintain blood pressure and organ perfusion by activating compensatory mechanisms. (increase heart rate, constricting blood vessels to redirect blood flow to vital organs)
Progressive (what has failed)
*Compensatory stage has failed
*CO decreases and BP decreases
*Anasarca (diffuse profound edema) decreasing blood flow to the pulmonary capillaries
*Hypoperfusion leads to ischemia of distal extremities
*complete deterioration of the cardiac system and thus all organ systems
Refractory stage
the body’s organs and tissues fail to receive sufficient oxygen and nutrients. Blood pressure remains critically low, and vital organs sustain irreversible damage, often leading to multi-organ failure and death
Hypovolemic shock def
inadequate intravascular vol leading to decreased tissue perfusion
*MOST COMMON FORM OF SHOCK
Patho of hypovolemic shock
loss of circulating fluid vol -> decrease in venous return -> decrease in preload -> decrease in CO and SV -> inadequate cellular o2 supply -> ineffective tissue perfusion
Absolute fluid loss through… (5)
*hemorrhage
*GI loss (v/d)
*fistula drainage
*DM
*Diuresis
(ex. trauma patients)
Relative fluid loss though… (3)
*fluid moves out of the vascular space into extravascular space
*intracativity space
*third spacing - fluid leaking from vascular space to interstitial space
(ex. burn patients)
Classifications of hypovolemic shock (4)
1: 15-20% vol loss (750mL)
2: 15-30% vol loss (750-1500mL)
3: 30-40% vol loss (1500-2000mL)
4: >40% vol loss (>2000mL)
S/S of hypovolemic shock (6)
*high HR
*norm to low BP
*Low CO (amount of blood pumped in 1 min) & CI (measure of CO per square meter of body surface)
*CVP (measure of BP in central veins)/wedge low
*SVR(resistance the arteries present to flow of blood) low
*UO low
RN interventions for hypovolemic shock: (8)
*enhance vol replacement
*minimize fluid vol loss
*maintain optimal cardiac contractility and CO
*maintain optimal o2 sats
*control body temp
*prevent injury caused by decreased perfusion
*maintain nutrition status
*maintain renal perfusion
RN interventions for hypovolemic shock: enhance vol replacement (2 + what type of volume)
*2 large bore IV caths: 18g+
*Volume!
1. crystalloids: isotonic saline 3ml for every 1ml lost
2. Hypotonic saline: when Na is high
3. warm fluids
4: colloids: albumin
5.Blood and blood product: increase o2 carrying capacity
RN interventions for hypovolemic shock: Minimizing vol loss (4)
*compression of compressible vessels
*surgery to control bleeding
*antidiarrheals
*blood transfusions
RN interventions for hypovolemic shock: maintain optimal cardiac contractility and CO (4)
*PA line readings Q1hr (best measure of pressure w/i the pulmonary artery
*Dobutamine for CO
*NaHCo3 if pH <7.0
*Hourly I&Os
RN interventions for hypovolemic shock: maintain optimal o2 sat (3)
*keep SpO2 >95% (start 5-6L/min NC)
*intubation is likely (monitor ABGs)
*Maintain bedrest and adequate rest periods
RN interventions for hypovolemic shock: control body temp (2 + why)
(why: overheating increases myocardial o2 consumption)
*tx hyperthermia w/ cooling blankets
*warm IV fluids
RN interventions for hypovolemic shock: Prevent injury caused by decreased perfusion (4)
*limit sedatives
*give meds through central line
*monitor cap refill
*monitor s/s of skin breakdown
RN interventions for hypovolemic shock: Maintain nutrition status (2)
*Enteral feeding tube
*monitor electrolytes
RN interventions for hypovolemic shock: maintain renal perfusion (5)
*insert FC and monitor I&Os
*monitor renal labs (BUN, Creat, etc)
*replace vol
*monitor urine color
*dobutamine: increases perfusion
What will a hypovolemic shock pt look like? (7)
*pale, cool skin
*weak or rapid pulse
*decreased BP
*altered LOC
*thirst
*anxiety/restlessness
*N/V
sepsis
systematic inflam response to infection
Severe sepsis
sepsis complicated by organ dysfunction
Septic shock
Presence of sepsis complicated by organ dysfunction
Septic shock:
presence of sepsis with hypotension despite fluid resuscitation -> inadequate tissue perfusion resulting in hypoxia
Septic shock factors (2)
*Intrinsic factors: internal or inherent qualities or characteristics
*Extrinsic factors: external influences or environmental conditions that impact an organism
Examples of intrinsic factors leading to septic shock (2)
*extreme age
*coexisting diseases: ex. burns, cancer, substance abuse, malnutrition, etc
Examples of extrinsic factors leading to septic shock (6)
*invasive devices
*med therapy
*fluid therapy
*surgical or trauma wounds
*surgical or invasive diagnostic procedures
*immunosuppressive therapy (chemo)
septic shock patho:
infection -> immune response -> inflamm -> HoTN -> decreased perfusion -> cellular damage -> impaired cellular metabolism
3 major patho effects of septic shock
*vasodilation
*maldistribution of blood flow
*myocardial dysfunction: decreased EF, ventricular dilation
s/s of septic shock (7)
*increased HR
*HoTN
*full bounding pulse
*pink, warm, flushed and then cold (warm better than cold sepsis)
*first increased RR then decreased RR
*decreased UO
*increased temp
What are ART lines used for and not used for? (3)
*Best continuous BP monitoring & Assessment of arterial waveforms: give info about cardiac status
*Blood sampling: ABG
*NOT used for giving fluids or drugs
Why do we measure arterial blood pressure through the ART line?
Most accurate and reliable measurement and available quickly
What type of patients would most likely require arterial line placement?
Critically ill patients, such as those in intensive care units (ICUs), post-operative patients, or those undergoing major surgeries, often require arterial line placement for continuous blood pressure monitoring and frequent arterial blood sampling.
Besides blood pressure monitoring and ABG sampling, what other information can be obtained from arterial lines?
Arterial lines provide valuable information about arterial waveforms, which can indicate changes in cardiac output, systemic vascular resistance, and arterial compliance. This helps clinicians assess the patient’s cardiovascular status and response to therapy.
Process of the arterial blood pressure waveform
Aortic valve opens -> 75% of the SV is ejected -> systolic pressure peaks -> 25% of the SV is ejected -> aortic valve closes
How do we want the arterial blood pressure waveform to look?
peaked not humped (means line is failing)
What does a widened pulse pressure on the arterial waveform suggest?
A widened pulse pressure, seen as an increased difference between systolic and diastolic pressures, may suggest conditions such as aortic regurgitation, arteriosclerosis, or increased stroke volume.
What is systolic arterial pressure
max pressure with which the blood is ejected from the left ventricle
Diastolic arterial pressure
reflects how rapid the blood flow through the arterial system and the vessel’s elasticity
what conditions/meds make BP higher
*HTN, epi, dopamine, levophed
What conditions/meds lower BP
*septic neurogenic shock, nipride
What is the MAP
average pressure occuring in the aorta and its major branches during cardiac cycle
necessary MAP to perfuse vital organs
60
MAP formula
SBP + (2x DBP)/ 3
What are pressors used for
HoTN, shock, sepsis
what do vasopressors do?
Increase afterload
Examples of vasopressors that increase afterload
*epinephrine
*Norepinephrine (Levophed)
*High-dose dopamine
STEMI: What (9)
*Cell death. Involved all 3 layers.
*QRS complex = altered shape.
*Q-waves = wider and deeper (giggity).
*ST- segment changes.
*Thrombolytics = yes
*Mechanical interventions = yes
*Tx protocols well tested.
*Easier to dx.
*Complete blockage of artery.
STEMI: Chest pain assessment (P-U)
P: What PROVOKES it? Where?
Q: QUALITY?
R: RADIATE? To what REGION?
S: SEVERITY 1-10? SYMPTOMS?
T: TIME pain started? TX before coming to ER?
U: UNDERSTANDING situation
STEMI: Common s/s of pain for men (6)
Severe chest pain > 30 minutes
New/different pain
More intense pain
Elephant on chest
Vise-like
Radiates down the left arm/jaw/neck/back
STEMI: Common s/s of pain for women (6)
Any of what the men get +
Unexplained SOB
Cold sweat
Sudden fatigue
Nausea
Lightheaded
STEMI: VS (4)
*HR up and then down
*RR up: O2 demand goes up but less is getting perfused to tissues
*BP up then down
*Temp goes up
STEMI: Clinical assessment-Skin
Assess skin temperature, color, cap refill, and other peripheral pulses: Circulation slows
STEMI: Clinical assessment-Heart
Auscultate heart sounds: Murmurs or new S3 and S4 (hard)
STEMI: clinical assessment- Lungs
*Auscultate lung sounds: Crackles and wheezes
*Observe for breathlessness and pink frothy sputum: Pulmonary edema
STEMI tx (3 immediate)
*Stop ischemia by decreases demand and improving supply
*12-lead EKG w/in 10 minutes of arrival!
*MONAB: Morphine, O2, Nitro, Aspirin, Beta-Blockers
STEMI: Analgesia
(this is super painful!)
*Morphine - 2-8 mg IV Q5-15 minutes (depends on BP b/c vasodilation)
*Control the environment: Extreme anxiety, Fear, Give info
STEMI: Oxygen tx
*O2 at 2L to keep sats > 90%
*HOB elevated (easier to breath, let gravity move diaphragm)
*IV access w/2 large-bore needles (at LEAST 20 but 18 is better)
1. NS
2. Thrombolytics
3. Morphine
STEMI: Monitor for complications
*Reactions to meds
1. Hypotension
2. HA
3. RR
4. Bleeding
5. Continue pain
STEMI: Lab studies (electrolytes)
altered K, Ca, and Mg
STEMI: Lab studies cardiac (bio markers)
*Cardiac enzymes: Proteins released from damaged myocardial cells
*Total CK: Released w/any muscle breakdown (not just cardiac muscle)
*CK-MB: Represents cardiac component
*CK-Index: Ratio of CK-MB to Total CK
*Myoglobin and Troponin 1: More sensitive for heart
STEMI: Coagulation studies (we want these in case we need to go to surgery)
- PT (Prothrombin time): If you give Coumadin
*PTT (Partial Prothrombin Time): If you give Heparin
*Anti-Factor Xa Assay: If you give Lovenox
STEMI: lab studies: CBC
Check the differential d/t tissue necrosis
STEMI tx: Percutaneous Coronary Intervention (PCI) possibilities (4)
*Angioplasty (PTCA): Balloon catheter is passed through the stenosis (plaque) and inflated with helium. It enlarges the diameter by compressing and splitting the plaque.
*Cardiac stent: Small spring device holds lining of vessel wall apart to maintain patency of the vessel
*Rotational Ablation (Rotoblator): High speed diamond-tipped (giggity) device that cuts the hard plaque but not the soft vessel wall. It pulverizes material into micro-debris
*CABG: Papillary muscle rupture. Acute ventricular septal defect. Left main coronary artery occlusion
If PCI for STEMI, what is the goal time from paramedics to balloon up in
90 minutes
STEMI: Fibrinolytics (what, when to give, contraindications, dx criteria)
*dissolves all clots
*give w/i 30 min of arrival, w/i 12 hrs of onset of pain
*Contraindications: recent surgeries, bleeding, pregnancy = result in hemorrhagic strokes
*Further contraindications: facial trauma, uncontrolled HTN, or ischemic stroke w/ mon
*CXR, and EKG
Bleeding precautions for fibrinolytics
*no razors, needle sticks, toothbrushes, or suppositories
*check stool for blood
*expect to see arrhythmias and elevated cardiac markers if med is still working
Anticoagulant/Antiplatelet Medications: Heparin
*Decreases thrombi formation, infarction rate, and DVTs
*Doesn’t work on the primary clot
*60 units/kg then start drip at 12 units/kg/hr
*Monitor PTT Q6hrs
*Keep PTT between 50-70
Anticoagulant/Antiplatelet Medications: Lovenox
Chromogenic anti-Xa Heparin assay
Anticoagulant/Antiplatelet Medications: ASA
*Decreases platelet aggregation
*Prevents further thrombosis
*Give as 4 low-dose ASA (May only give 2 when in combination with TNKase)
Anticoagulant/Antiplatelet Medications: Plavix
*Blocks platelet aggregation
*300-600 mg loading dose, then 75-150 mg maintenance dose
Beta blockers
*Lower HR
*Lower O2 consumption
*Lower dysrhythmias (ventricular)
*Contraindications: HF, Low CO, Heart block, Active asthma
Vasodilator drugs:
Nitro: spray, SL, PO, topical, IV
STEMI: secondary prevention meds
*ACE inhibitors
*Diuretics
*Antihyperlipidemics
STEMI: secondary prevention meds (ACE inhibitors)
*(Captopril, Vasotec, Prinivil) w/in 24 hours after STEMI
*Action: Slows progression of L ventricular dysfunction
*Dose: Dependent on the drug and reason
STEMI: secondary prevention meds (Diuretics)
if heart failure is present
STEMI: secondary prevention meds (Antihyperlipidemics)
if total cholesterol, LDL, triglycerides are elevated
STEMI: Post-cardiac syndrome
*Therapeutic Hypothermia:
-Increased neurologic function
-Increased survival rate
-33 degrees for 12-24 hours
NSTEMI (8)
*Blood supply to heart is inadequate but without cell death.
*Damage to part of a wall, not full-thickness.
*No ST changes.
*No thrombolytics.
*Tx w/mechanical interventions on a less emergent basis.
*Less well tested protocols.
*More difficult to dx.
*Partial occlusion of artery.
ACLS scenario: Bradycardia
P/R check
BP check
*Atropine Q4 minutes, max 3 mg (reflex brady)
P/R check
BP check
H&T
P/R check
BP check
*Atropine 1 mg
BP check
P/R check
BP check
~ 2 minutes ~
P/R check
BP check
Placer pads IMMEDIATELY
ROSC?
ACLS Scenario: Pulseless Asystole/PEA
P/R check
CPR
*Epi 1 mg Q2 min, no max
Call RT/intubate
P/R check
CPR
P/R check
CPR
*Epi 1 mg
P/R check
CPR
H&T
P/R check
CPR
*Epi 1 mg
ROSC?
ACLS Scenario: Tachy w/o Pulse AND Tachy w/Pulse
P/R check
Stable?
Cardiovert 100 J
Pulse?
Rhythm change? Go to that algorithm
ACLS Scenario: V-Fib/Pulseless V-Tach
P/R check
Defib 120 J
CPR
P/R check
Defib 150 J
CPR
Epi 1 mg
Call RT/Intubate
P/R check
Defib 200 J
CPR
Amiodarone 300 mg OR Lidocaine 1-1.5 mg/kg
H&T
P/R check
Defib 200 J
CPR
Epi 1 mg
P/R check
Defib 200 J
CPR
Amiodarone 150 mg OR Lidocaine 0.5-0.75 mg/kg
P/R check
Defib 200 J
CPR
Epi 1 mg
P/R check
Defib 200 J
CPR
P/R check
Defib 200 J
CPR
Epi 1 mg
ROSC?
ACLS scenario: ROSC
*Mange airway
- Start 10 breaths/min
- SpO2 92-98%
- PaCO2 35-45 mmHg
*Manage hemodynamic parameters
- Systolic BP > 90 mmHg
- MAP > 65 mmHg
*Obtain 12-lead EKG
*Consider for emergent cardiac intervention if:
- STEMI
- Unstable cardiogenic shock
- Mechanical circulatory support required
*Follows commands?
Yes:
- TTM
- Obtain brain CT
- EEG monitoring
- Other critical care management
No:
- Other critical care management
* Evaluate and tx rapidly reversible etiologies
*Involve expert consultation for continued management
ABG analysis: PH
*normal range: 7.35-7.45
*If pH <7.35 = acidic
*if pH >7.45 = alkaline/basic
*If pH is out of wack at all, it is uncompensated
ABG Analysis: CO2
*normal range: 35-45
*Respiratory level
*Opposite of pH readings. This bitch is acidic and problematic so we don’t “read” her like the other girls who are more basic. More of her means more acidity. Less means more basic.
*<35 = alkaline/basic
*>45 = acidic
ABG analysis: HCO3
*Norm range = 22-26
*Metabolic level
*Interpreted just like PH. Lower number? = more acidic
