02 - Basic EKG Review

Question 1

What is included in the AANA & ASA standards of basic monitoring?

Answer 1

Continuous ECG, Pulse ox, Temp, Ventilation, HR & BP every 5 min at least

*basic monitoring is meant to insure patient safety, cover ABCs

Question 2

What is the purpose of the ECG monitor?

Answer 2

• Gives us a picture of the heart
• Lets us know how the patient is doing
• Always relate the rhythm seen to other data to get the whole clinical picture
• Base treatment decisions on the whole picture

Question 3

What two leads are typically monitored for ECG? Why?

Answer 3

Usually lead II and V5

Looks at both sides of the heart – RCA and the left side

Question 4

What are the steps in rhythm identification of an ECG?

Answer 4

• Is it regular?
• Is there P waves, are they regular in size and shape?
• Does the QRS follow every P wave?
• Are they regular in size and shape?
• What are all the intervals?
• What does the ST segment look like?
• What does the QT look like?
• Are there any aberrant beats?

Question 5

What steps should you go through if there is a rhythm change?

Answer 5

• Look to see how the pt is tolerating the change
• Think of what may have caused the change
• Base treatment on the answers from above
• Think of the risks of your treatment, and the risk of doing nothing
• Know how long you have to act – its a guess

Question 6

What are the causes and treatment of Sinus Tachycardia?

Answer 6

HR > 100 (relative)

Causes: sympathetic stimulation, pain, hypovolemia, ischemia, impending CHF

Treatment: control pain, increase anesthetic depth, volume, beta blocker
*only use BB after doing the previous treatments – it is a last resort treatment

Question 7

What are the causes and treatment of Sinus Bradycardia?

Answer 7

Sinus with HR < 60 (relative)

Causes: reflexes, volatile agents (Iso - too deep), loss of sympathetic tone, digoxin toxicity

Treatment:

• removal of offending agent (tugging on the eye, insufflation)
• atropine or glycopyrrolate
• inotropic agents (beta agonists)
• sympathomimetics (role of Phenylephrine and Ephedrine)

Question 8

What are the causes and treatment of atrial fibrillation?

Answer 8

Irregular R-R, absence of P waves — Controlled if rate <100, likely chronic

Causes: mitral valve disease, CHF, hypoxia, hypovolemia, ischemia, electrolytes, cardiac surgery

Treatment: assess tolerance of loss of atrial kick, continuous fluids, reverse hypoxia, beta blockers, amiodarone, cardioversion
-less likely = diltiazem gtt (myocardial depressant on top of volatile agent), digoxin, procainamide

• *Caution - Ca+ blockers and anesthetics do not mix
• *Look for anticoagulant while doing preop

Question 9

What are the causes and treatment of Atrial Flutter?

Answer 9

Sawtooth P wave pattern – Atrial Rate >150 and Ventricular Rate is variable

Causes: HTN, COPD, CAD, Dilated cardiomyopathy, ETOH intoxication, thyrotoxicosis

Treatment: if compromised, cardiovert (be ready to pace)
-beta blockers, calcium channel blockers, amiodarone

• May diagnose with carotid massage or adenosine
• Usually paroxysmal, may convert to NSR or A-Fib

Question 10

What is a AV Junctional Rhythm? How do you treat it?

Answer 10

• Narrow QRS, retrograde, inverted or absent P wave
• Rate usually <60 (if >60 then it is accelerated junctional)
• common during GA, resolves on its own
• if accelerated, consider digoxin toxicity, MI or stress of recent cardiac surgery, also hx of rheumatic fever
• May not respond to atropine, ephedrine may work
• Consider beta blocker to relieve ischemia (common reperfusion rhythm)
• Consider temporary pacing if hemodynamic compromise

Question 11

What is Accelerated Idioventricular Rhythm? Causes?

Answer 11

• Uniform widened QRS rate <60
• Considered “slow VT” if 60-100

Causes: MI, reperfusion of cardiac surgery, digoxin toxicity, rheumatic fever, cardiomyopathy

• sign of a sick heart, rarely responds to atropine
• avoid the urge to use lidocaine (will worsen the “escape rhythm”) – instead try to relieve ischemia
• be ready to pace

Question 12

What are the causes and treatment of Ventricular Tachycardia?

Answer 12

Uniform, widened QRS, rate 100-250

Causes: CAD, ventricular dysfunction, recent MI (<96hr), cardiomyopathy, hypokalemia, low Mg, central line placement

Treatment: depends on rate & duration, tolerance, extent of known disease

• amiodarone, lidocaine, possibly procainamide
• ICD placement

Question 13

What are the causes and treatment of Torsades de Pointes?

Answer 13

Continuously changing, widened QRS, looks like “twisting around a point”

Causes: R on T phenomena (reason for synchronized cardioversion), ischemia

Treatment: magnesium, cardioversion – placement of ICD

• may terminate spontaneously or degenerate to VF
• if associated with relative bradycardia, consider Isuprel, Epinephrine, overdrive pacing

Question 14

What is the treatment of Ventricular Fibrillation? (ACLS algorithm)

Answer 14

• High Quality CPR
• Shock
• CPR, Access
• Shock
• Epi, Shock (Vasopressin no longer in ACLS)
• Amiodarone (or Lidocaine), -Shock
• CPR, shock, repeat, think 5Hs and 5Ts
• Where is AIRWAY (when it is convenient
• CPR and SHOCKING are the most important components*

Question 15

What are the 5 H’s and 5 T’s?

Answer 15

Hypovolemia
Hypoxia
Hydrogen ion
Hypo/hyperkalemia
Hypothermia

Tension Pneumothorax
Tamponade, Cardiac
Toxins
Thrombosis, Pulmonary
Thrombosis, Coronary

Question 16

What are the different heart blocks?

Answer 16

First Degree Block – long PR

Second Degree Block (Mobitz 1) – prolonging PR until dropped QRS

Second Degree Block (Mobitz 2) – no pattern, dropped QRS

Third Degree Heart Block

Question 17

What leads look at the inferior side of the heart? What vessel correlates?

Answer 17

II, III, aVF

RCA

Question 18

What leads look at the lateral side of the heart? What vessel correlates?

Answer 18

I, aVL, V5-V6

Left Circumflex

Question 19

What leads look at the anterior side of the heart? What vessel correlates?

Answer 19

I, aVL, V1-V4

LAD and Left Circumflex

Question 20

What leads look at the anteroseptal side of the heart? What vessel correlates?

Answer 20

V1-V4

LAD

Question 21

What happens to a pacer when you place a magnet?

Answer 21

It will convert it to DOO/VOO, rate typically 85 (Medtronic)

-removing the magnet will make pacer resume original setting

• ALWAYS have a magnet available during surgery
• Encourage bipolar not monopolar cautery (ground away from pacer)

Question 22

What do the 1st, 2nd, and 3rd letters of pacer settings stand for?

Answer 22

1st = Chamber Paced (A,V,D,O)
2nd = Chamber Sensed (A,V,D,O)
3rd = Mode of Response (triggered, inhibited, dual)

Occasionally:
4th = programmability, communication, & rate modulation (P, M, C, R, O)
5th = antitachyarrhythmia/ defibrillation functions (P, S, D, O)

Question 23

What is an ICD?

Answer 23

Internal cardiac defibrillator

• programmed to try to overdrive pace out of VT, will deliver shock if necessary
• shocking capacity may be turned off for surgery, may sense cautery as VF and shock it if not disabled
• must reprogram in PACU if deactivated

Use Magnet for ICDs (turns off shocking capacity but doesn’t affect pacer portion)

Question 24

What are the anesthetic considerations for placement of pacemakers?

Answer 24

• May be done under local or MAC (we are rarely involved unless pt is really sick)
• May be for lead changes in MOR
• ICDs may occasionally be done under MAC, may need heavy MAC for programming
• Fluoro may be used

*Communication w/ Cardiologist is essential

Question 25

What are the considerations for anesthesia in the EP lab?

Answer 25

- May be MAC or GA or both - May be for device, lead removal or replacement, cardioversion or more commonly AF/VT ablation - If GA, need to go to recovery after procedure - Risks of procedures determine level of monitoring you will do, plan for the worst - Don't rely on the cardiologist for arterial line, place your own if indicated - Requires fluoro and lead