Nurse Vicki's Critical Care

Front 1

Formula & Normal Value of: CO

Back 1

Cardiac Output-
CO = HR x SV
4-8L/min

Front 2

Formula & Normal Value of: CI

Back 2

Cardiac Index-
CI = CO/BSA
2.5-4 L/min/m^2

Front 3

Formula & Normal Value of: MAP

Back 3

Mean Arterial Pressure-
MAP = [SBP + (DBP x 2)] / 3
70 - 100 mmHg

Front 4

MAP Importance

Back 4

Reflects changes in the relationship btwn CO & SVR which reflects arterial pressure in the vessels perfusing the organs.
**it is the most reliable indicator of systemic tissue & organ perfusion.
**maintain above 60mmHg

Front 5

Formula & Normal Value of: RAP

Back 5

Right Atrial Pressure-
Direct Measurement
2-6mmHg

Front 6

Formula & Normal Value of: PAWP, PCWP, PAOP

Back 6

Pulmonary Capillary Wedge Pressure-
Direct Measurement
8-12mmHg

Front 7

Adenergic Receptor =

Back 7

specfic site located on cell surfaces where NT (i.e. epinephrine, norepinephrine) normally bind & produce a physiologic response.

Many drugs act by either blocking or stimulating these adrenergic receptors.

Front 8

Where are Alpha 1 receptors located & what is there response to stimulation?

Back 8

Blood vessels & vasoconstriction

Front 9

Where are Beta 1 receptors located & what is there response to stimulation?

Back 9

Heart & increase HR & increase contractility

Front 10

Where are Beta 2 receptors located & what is there response to stimulation?

Back 10

Blood vessels & Bronchioles & Uterus & GI tract

Vasodilation & relaxation of smooth muscles

Front 11

Where are dopaminergic receptors located & what is there response to stimulation?

Back 11

Renal vasculature & Renal vasodilation

Front 12

Where are vasopressin receptors located & what is there response to stimulation?

Back 12

Vascular smooth muscle & vasoconstriction & bronchoconstriction

Front 13

Formula & Normal Value of: PAWP, PCWP, PAOP

Back 13

Pulmonary Capillary Wedge Pressure-
Direct Measurement
8-12mmHg

Front 14

Adenergic Receptor =

Back 14

specfic site located on cell surfaces where NT (i.e. epinephrine, norepinephrine) normally bind & produce a physiologic response.

Many drugs act by either blocking or stimulating these adrenergic receptors.

Front 15

Where are Alpha 1 receptors located & what is there response to stimulation?

Back 15

Blood vessels & vasoconstriction

Front 16

Where are Beta 1 receptors located & what is there response to stimulation?

Back 16

Heart & increase HR & increase contractility

Front 17

Where are Beta 2 receptors located & what is there response to stimulation?

Back 17

Blood vessels & Bronchioles & Uterus & GI tract

Vasodilation & relaxation of smooth muscles

Front 18

Where are dopaminergic receptors located & what is there response to stimulation?

Back 18

Renal vasculature & Renal vasodilation

Front 19

Where are vasopressin receptors located & what is there response to stimulation?

Back 19

Vascular smooth muscle & vasoconstriction & bronchoconstriction

Front 20

CVP is...

Back 20

Central venous pressure = RAP
*measures the venous return to the heart & general fluid status.
*it is also the right heart preload measurement
*Used to approximate RVEDP (= RV function)
****NORMAL VALUE: 2-6mmHg

Front 21

CVP is increased with...

Back 21

-Fluid overload
-Cardiac tamponade
-Right heart dysfunction
- Right ventricular infarct
-Constrictive pericarditis
-Tricuspid stenosis/insufficency
-Pulmonary HTN

Front 22

CVP is decreased with...

Back 22

-dehydration
-volume loss
-venodilation

Front 23

PAP, PA pressure is...

Back 23

Pulmonary Artery Pressure-
*Blood pressure in the pulmonary artery
*Normal: 20-30mmHg (Systolic)
*Normal: 10-20mmHg (Diastolic)

Front 24

PAP is increased when...

Back 24

-atrial or septal defects
-pulmonary HTN
-COPD/emphysema
-pulmonary embolus
-pulmonary edema
-LV failure
-mitral stenosis

Front 25

PCWP/PAOP is increased when...

Back 25

-fluid overload
-mitral valve stenosis
-aortic stenosis or regurg
-LV failure
-constrictive pericarditis or tamponade

Front 26

PCWP/PAOP is decreased when...

Back 26

hypovolemia & vasodilation

Front 27

PVR is increased with...

Back 27

-pulmonary HTN
-pulmonary embolism
-pumonary vasculitis or hypoxia

Front 28

PVR is decreased with...

Back 28

-medications such as calcium channel blockers, aminophylline, or oxygen delivery

Front 29

RVP normal values

Back 29

diastole 0-8mmHg
systole 15-30mmHg

Front 30

PAP normal values

Back 30

diastole 8-15mmHg
systole 15-30mmHg

Front 31

PCWP normal values

Back 31

8-12mmHg

Front 32

LAP normal values

Back 32

4-12mmHg

Front 33

LVP normal values

Back 33

diastole 4-12mmHg
systole 110-130mmHg

Front 34

aortic pressure normal values

Back 34

diastole 70-80mmHg
systole 110-130mmHg

Front 35

S1 is...

Back 35

*mitral & tricuspid valves closing
*it is the end of diastole & begins ventricular systole

Front 36

S2 is...

Back 36

*closure of aortic & pulmonic valves

Front 37

SA Node

Back 37

Sinoatrial Node
-chief pacemaker of heart
-inherent rate 60-100bpm
-travels to AV node after impulse is generated here

Front 38

AV Node

Back 38

Atrioventrical Node
-recieves signal from SA node
-DELAYS relay to the bundle of his to allow the atria to empty for longer (allowing ventricals to fill more)
-inherent rate 40-60bpm

Front 39

Bundle of His

Back 39

-relays impulse from AV node to L & R bundle branches
-inherent rate is 20-40bpm

Front 40

P wave is & represents...

Back 40

-Atrial depolarization
-Shows the initial impulse & the impulse traveling to the AV node (by the end of the p wave)

Front 41

PR interval is & represents...

Back 41

-isoelectric line after p wave is P-delay of signal in the AV node (on its way to bundle of his)
-PR interval is from start of P wave to begining of QRS complex
-should be 0.12-0.2 sec
->0.2 means you have a 1st deg heart block

Front 42

QRS is & represents...

Back 42

-ventricular depolarization & atrial repolarization (which is not seen bc it is overshadowed by the ventricular depolarization)
-should be 0.40-0.12 sec
-widened QRS means

Front 43

QT interval is & represents...

Back 43

-ventricular repolarization & recovery
-should be 0.42 -0.48 sec

Front 44

T wave is & represents...

Back 44

-absolute refractory period (at peak of t wave)
-relative refractory (can fire with strong impulse, half way down t wave)
-supernormal (at end of t wave)

Front 45

Amiodarone basics

Back 45

Class III antiarrhythmic
-inhibits adrenergic stimulation
-prolongs action potential & refractory period
-decreases AV conduction & SA node firing

Front 46

Amiodarone is used for...

Back 46

-wide variety of atrial & ventricular tachyarrhythmias
*controls ventricular rate in pts with rapid A-fib & A-flutter when other therapies are ineffective
*Adjunct therapy to electrical cardioversion of refractory supraventricular tachyarrhythmias (afib/aflut)
*controls stable VT & widecomplex tachycardias or uncertain origin
*cardiac arrest from persistent VT and VF

Front 47

Amiodarone dosages...

Back 47

Cardiac Arrest =
*300mg (diluted in volume of 20-30mL NS or D5W) by IV Push
*Consider repeat doses of 150mg IV push q 3-5 min
*If defibrillation is successful, follow with a continuous infusion
*MAX daily dose 2.0 g IV/24 hours

Non-Cardiac Arrest =
*150 mg IV over 10 min (15mg/min)
followed by 1 mg/min continuous infusion for 6 hours
then 0.5 mg/min for 18 hrs

Front 48

Amiodarone nursing considerations...

Back 48

*hypotension & bradycardia may occur and can be prevented with slowing infusion rate (might require fluids, vasopressors, temporary pacing to fix)
*May have negative inotropic effects
*May prolong QT interval (dont give with drugs that also do this, procainamide)

**it potentates warfarin (coumadin) so warfarin dose must be reduced and INRs closely monitored
**elevation of digoxin levels is also common
**Can cause significant AV node depression especially in combo with beta-blockers & calcium channel blockers

Front 49

Diltiazem (Cardizem) is...

Back 49

Calcium Channel Blocker
-inhibits calcium ions from entering the "slow channels" of vascular smooth muscle during depolarization. This produces relaxation for coronary muscle & vasodilation. Also helps to increase oxygen availablity for pts with vasospastic angina.
-It also has a depressent effect on AV node conduction & increases refractory period, means its effetive for slowing ventricular response to Afib/Aflut

Front 50

Diltiazem (Cardizem) is used for...

Back 50

*to terminate & prevent arrhythmias
*to slow the ventricular response to AFib & Aflutter

Front 51

Diltiazem (Cardizem) dosage...

Back 51

15-20 mg (0.25mg/kg) IV slowely over 2 minutes
-may repeat after 15 minutes @ 20-25mg (0.35mg/kg) IV over 2-5 min

*maintenance infusion 5-15mg/hr, titrated to heart rate

Front 52

Diltiazem (Cardizem) nursing implications...

Back 52

*may cause transient decrease in BP due to peripheral vasodilation
*contraindicated for pts receiving IV beta-blockers (use caution with oral)
*avoid or use with caution in pts with sick sinus syndrome or AV block in the absense of a functioning pacemakers.
*contraindicated in pts with severe hear failure

Front 53

What is the antidote for Cardizem?

Back 53

Calcium chloride is antidote for effects from calcium channel blocker overdose

Front 54

ABGs allow you to assess two main concepts...

Back 54

1. PaO2 = efficiency of gas exchange
2. PaCO2 = effectiveness of ventilation (how well toxins are being removed)

Front 55

pH normal range and average

Back 55

7.35 - 7.45
average = 7.4

Front 56

Normal range for sodium

Back 56

Na is 135-145

Front 57

PaCO2 normal range and average

Back 57

Partial pressure of carbon dioxide in the blood.
Normal Range 35-45 mmHg
Average 40 mmHg

Front 58

HCO3 normal range and average

Back 58

Bicarb: 22-26 mEq/L
average 24 mEq/L

Front 59

PaO2 normal range and average

Back 59

Partial pressure of Oxygen in blood
*as we age this can go lower
80-100 mmHg
average 95 mmHg

Front 60

SaO2 normal range and average

Back 60

Saturation of O2
Normal Range: 95-100%
Average 96%

Front 61

FiO2

Back 61

fraction of inspired oxygen

Front 62

respiration

Back 62

the exchange of oxygen and carbon dioxide by the lung

Front 63

ventilation

Back 63

movement of air btwn the atmosphere and the alveolus

Front 64

perfusion

Back 64

the flow of blood through the lungs

Front 65

diffusion

Back 65

the mechanism for transfer of gases at the alveolar-capillary membrane

Front 66

hypoxia

Back 66

reduced oxygen in the tissues

Front 67

hypoxemia

Back 67

reduced oxygen in the blood

Front 68

atelectasis

Back 68

collapse of the alveoli

Front 69

SpO2

Back 69

Saturation of peripheral O2
*pulse oximetry is standard for this

Front 70

BE

Back 70

Base excess tells how much base and acid you have.
*Normal range: -2 to +2

Front 71

What is the critical value for PaO2 & what do you do if its below

Back 71

60mmHg is the critical value indicative of hypoxemia and mandates use of supplemental oxygen.

*45mmHg represents a threat to life

Front 72

Advantages of SpO2 Monitoring

Back 72

non-invasive (fingertip or forehead, etc)

Front 73

Disadvantages of SpO2 Monitoring

Back 73

-no info on the HgB (they could have okay SpO2 levels but not enough Hgb to transport O2, i.e. anemic ppl can have fully saturated blood yet not enough O2 for body)
-no info on the CO2 retention
-no info on CO
-inabillity to monitor or false info (things that interfere with reading: nail polish, light, motion artiface, dyes, vasoconstriction, sweating)

Front 74

Obtaining the ABGs

Back 74

*Arterial blood specimen is taken using a heparinized syring
*All air bubbles are removed
*Specimen is immediately taken to the lab to be analyzed (often on ice to slow metabolism of oxygen)
*Document the FiO2 during the test, mode of administration, respiratory rate, and pts temperature & this should go with the specimen

Front 75

Steps for Assessing ABGs

Back 75

Step 1 = pH classification
Step 2 = PCO2 Classification
Step 3 = HCO3 Classification
Step 4 = Compensated or not?
Step 5 = evaluate the PaO2

Front 76

Step 1 Assessing ABGs

Back 76

-pH classification
-either acidemia or alkalosis
-it is based on which side of 7.0 its on, regardless of if it is or is not in normal range

Front 77

Step 2 Assessing ABGs

Back 77

PCO2 classification
-changes are r/t lung function
-in primary respiratory problems the pH and PCO2 will change in OPPOSITE directions (pH down PCO2 up = respiratory acidosis/ pH up PCO2 down = respiratory alkalosis)

Front 78

Step 3 Assessing ABGs

Back 78

HCO3 Bicarb Classification
-METABOLIC INDICATOR
-changes here are r/t actions by the kidney
-In primary metabolic problems the pH and HCO3 will change in the SAME DIRECTION (i.e. pH up, HCO3 down =metabolic acidosis >26/ pH down, HCO3 up = metabolic alkalosis <22)

Front 79

Step 4 Assessing ABGs

Back 79

determine if its compensated or not.
*if its in range = compensated
*if its <7.35 or >7.45 then its not compensated