exam 1 High Acuity Cardiac lecture

Closed ICU

patient care is provided by a dedicated ICU team that includes a CC physician

Open ICU

care is provided by a team with doctors who have responsibilities outside of the ICU

SBAR

Method of communication among professionals. Required info.S--SituationB--BackgroundA--AssessmentR--RecommendationImportant when contacting a physician for a patients needs

characteristics of critically ill patients

resiliency, vulnerability, stability, complexity, predictability, resource availability, participation in care, participation in decision making

Role of sedation in Critical illness

Reduces anxiety, reduces agitation, helps provide amnesiaImportant to provide adequate pain control FIRST

What is a "sedation vacation"?

Titration down of sedation medications once every 24 hours before the doctor rounds so they can perform an appropriate assessment.

do you want a family to see a Code BLUE?

Yes. It gives families insight that all was done that could be done for the family member.

how long should a PR interval be?

5 little blocks or 0.20

how long should a QRS complex be?

3 little blocks or 0.12

How long should a QT interval be?

10 little blocks or 0.40

Steps to analyzing a rhythm strip

1. Are QRS's present?2. Are the R-R intervals regular? (Sinus or not?)3. What is the rate? Is it normal, tachy or brady?4. Are P-waves present before each QRS? (absence of P waves indicates Heart block)5. Measure the PR interval6. Measure the QRS complex and the QT interval7. Look for ST changes.

what does the P wave indicate?

atrial depolarization from the SA node

Types of rhythms that originate in the SA node

Sinus RhythmSinus BradySinus Tachy

Rhythms that originate in The Atria

Atrial flutter (saw tooth)Atrial fibrillationSVTPremature atrial complexes

Rhythms originating in AV Node

Junctional Rhythm

Rhythms that originate in ventricle

Ventricular fibrillationVtachAsystoleTorsades de pointesPacemaker rhythmsPVC'sIdioventricular rhythms

Hypokalemia effect on heart rhythms

PRI increases, T wave is flat, QT interval lengthens, Brady-dysrhythmias, conduction blocks, PVC's

HYPERkalemia and the heart

Tall peaked T wave, QT shortens, if not treated b/c asystole

HYPERcalcemia and the heart

QT intervals shortens

HYPOcalcemia and the heart

QT interval lengthens

HYPERmagnesemia and the heart

PRI prolongs, QRS widens, tall peaked T waves, Bradycardia

First degree heart block

PRI less than 5 blocks

second degree AV block, Type I Wenckebach

Gradual lengthening of the PR interval until a QRS complex is droppedCauses: Surgery near valves, inferior or posterior MI, Dig toxicity.

second degree AV block, Type II Mobitz

Every other p wave not conducted through the AV nodeCaused by: Inferior MImanifestations: Possibly none, hypotension, S/S of decr perfusionMay deteriorate to complete HB

3rd degree AV block--Complete heart block

Asynchronous contraction of the atria and the ventriclesCaused by Acute MIManifestations are shock and loss of consciousness

Junctional rhythms

SA node sin't firing and the rhythm originates in the AV node. P wave is inverted, absent or behind QRS complex. Caused by: vagal stimulation, hypoxia, SA node ischemia, Dig toxicity.

Ventricular rhythms

Origin of depolarization is in the ventriclesMay be fast or slowQRS is bizarreWide QRS= VtachNarrow QRS=SVT

Idioventricular Rhythm

Regular rhythm, rate of 20-40Caused by severe hypoxia or MI

accelerated idioventricular rhythm

Looks like IVR except can be regular or irregular with a rate of 40-100. Caused by AMI, reperfusion

Ventricular Tachycardia

Rapid rhythmic contraction of the ventriclesNo P wavesWide bizarre complexesCaused by Heart disease, hypokalemia, hypoxia

Torsades de Pointes

Oscillating ventricular rhythm, rate >200Caused by Prolonged QT interval of >0.40, quinidine or procainamide, heart disease, hypokalemia, hypoxia

Ventricular fibrillation

Uncoordinated electrical activityNO cardiac outputCaused by heart disease, hypokalemia, hypoxiaTREATMENT: DEFIB!VFIB=DEFIB

Pulseless Electrical Activity (PEA)5 H's and 5 T's

5 H'sHypovolemia, hypothermia, hydrogen ion (acidosis), hypoxia, hyperkalemia5 T'sTablets (OD), Tamponade, Tension pneumo, Thrombosis in ACS or Thrombosis in Pulmonary.

AVPU measures what?

ResponsivenessA--AlertV--VoiceP--PainU--Unresponsive

if found to be unresponsive, then what do we look for--

ABC's

If responsive, next steps in assessment

OIMFO--oxygenI--IV accessM--MonitorF--Fluids

Slow Narrow QRS complexes interventions

1. OIMF2. Assess QRS width3. If <0.10 intervention sequence a. Atropine 0.5 to 1.0 mg IVP (up to 3 doses) b. Transcutaneous pacing c. Dopamine 5 to 20 per minute d. Epinepherine 2-10 mcg

Slow WIDE QRS complexes interventions >0.10

1. Go directly to TCP2. Dopamine 5-20 per minute3. Epinepherine 2-10 mcg4. Prepare for Transcutaneous pacingDo not give atropine!

Fast rhythms with QRS <0.12 interventions

OIMF then assess for stability.If unstable, synchronized cardioversion

Synchronized Cardioversion

Low dose electrical therapy delivered on the QRS complex.Oh Say It Isn't SoOh O2 with sat monitorSay SuctionIt functional IVIsn't equipment for intubationSo sedation plus analgesia

What do you premedicate with for cardioversion?

Sedation and analgesia--Sedatives: Versed, fast acting barbituates, etomidate, ketamineAnalgesia: Fentanyl, morphine, merperidine

cardioversion process

100, 200, 300, 360. Shock once each time and check for rhythm. when reaches 360 shock and then shock again.

Stable Regular Narrow QRS Complex tachycardia interventions

ID the rhythm then:VACVagal maneuvers, Adenosine (very fast--6-6-12)Cardiazem

Fast IRREGULAR narrow QRS complex rhythms

Control the RATE first with cardiazem or beta blocker

How do you control a rhythm???

If less than 48 hours use cardioversion and AmiodaroneIf more than 48 hours, anticoags for 3 weeks THEN cardioversion

STABLE ventricular tachycardia treatment

OIMF, Amiodarone or lidocaine IV, cardioversion if unresolved.

Torsades treatment

Mag Sulfate 2G IV

UNSTABLE ventricular tachycardia

Go immediately to cardioversion, premedicate whenever possible with Versed

Ventricular Fibrillation/Pulseless V-Tachy

DEFIBRILLATE! Vfib-DfibSCREAMS--shock 360 (monophasic) or 200 (biphasic) onceC--CPRR--Check rhythm in 2 minutesE--Epi 1 mg IV push, repeat every 3-5 mins or Vasopressin 40 U IV, single doseAM--Antiarrhythmic meds (Amiodarone or lidocaine)

Asystole or Agonal rhythm interventions

Check another leadGive Epinepherine 1 mg IV push, repeat every 3-5 minutes OR vasopressin 40 U IV single dose, Atropine 1 mg IVP repeated every 305 mins PRN to a total dose of 0.04 mg/kg

Defibrillation

The therapeutic use of electrical current to deliver large amounts over a very brief period of time. Used for V Fib

Synchronized Cardioversion

Uses a lower dosage of electrical current for termination of V tach, SVT and atrial rhythms with rapid ventricular responses.

Phases of cardiac cycle affected by medications

Phase 0--Fast influx of Na causing rapid depolarizationPhase 1--inactivation of Na channels causes early repolarizationPhase 2--slow influx of Ca that prolongs contraction of cardiac musclePhase 3--Calcium channel closes, potassium channels open causing rapid repolarizationPhase 4--resting membrane potential

Class 1 drugs

Slows the rapid influx of Na prolonging the absolute refractory period therefore decreasing premature depolarizations and depressing automaticity. Quinidine and procainamide block fast Na channels and phase 3 prolonging action potentialLidocaine blocks fast Na channels and accelerates phase 3 shortening the action potential.

Class 2 drugs--Beta Blockers

compete with endogenous catecholamines for receptor sites causing the depression of spontaneous depolarization leading to delayed impulse conduction. esmolol, metoprolol

Class 3 Potassium channel blockers

slows phase 3 depolarizationAmiodarone for atrial or ventricularIbutilide for supraventricular rhythms

Class 4 Ca channel blockers

inhibit the influx of Ca in phase 2 prolonging depolarization in the atria, SA and AV nodes. Examples: Verapamil, Cardiazem (Diltiazem)

Other cardiac drugs

Adenosine--Blocks conduction thru the AV node converts SVT to NSRAtropine--Blocks the effects of Ach in the atria, SA and AV nodes nullifying the influence of the vagus nerve BradycardiaEpinephrine--Stimulates the alpha and beta receptors in the heart given when dead.