Orientation EKG

THOMPSON VALLEY EMS : THOMPSON VALLEY EMS EKG ORIENTATION-PARAMEDIC LEVEL

OBJECTIVE STATEMENT : OBJECTIVE STATEMENT Public expectation of pre-hospital medicine has evolved over the last twenty years. EKG interpretation and cardiac treatment is a key component and often encountered in the TVHSD. Cardiac alert program is one of the most successful in the USA.

GOALS OF 12 LEAD ORIENTATION : GOALS OF 12 LEAD ORIENTATION Familiarize students with the Cardiac Alert Program. Refresh students in knowledge regarding MI patterns, Bundle Branch Blocks, Wide beat tachycardia's, and some special EKG criteria situations Review importance of History taking and examination and the important components of those areas Discuss the role of the 12 lead

Assessment : Assessment Assessment is a combination of History, examination of the patient, and interpretation and application of the 12 lead. Assessment is on going and should be done after treatments have occurred, when patient condition changes, and at regular time intervals

History : History Studies have shown that a history taken by an experienced clinician is more accurate in predicting ischemic heart disease than any single available test with the exception of coronary arteriography. Knowing what to ask and when is essential.

Essential Baseline Questions : Essential Baseline Questions Questions that must be asked of patients with Chest Pain, Cardiac History, Syncope, or of patients with whom the Paramedic has a high index of suspicion.

Basic Essential Questions : Basic Essential Questions When did the discomfort begin? Where do they feel it? Does it radiate? How would they describe it in their own words? Is it constant or does it come and go? Is it similar to any past episodes?

Essential Questions Continued : Essential Questions Continued Does anything make it better or worse? What is the patients previous History? (diabetic, htn, cardiac, abdominal pain, clotting issues, dysrhythmias) What medications are they on?

Exam : Exam Skin color, temperature, and condition SOB] Nausea or Vomit Anxiety or denial Edema-extremities vs.. Pulmonary JVD Breath Sounds

Exam Continued : Exam Continued S 3 or S 4 Gallup/muffled heart tones Vital Signs Rhythm Mentation Syncope

Combine History and Exam : Combine History and Exam Suspicion of AMI is based entirely on field history. Do NOT be reassured by normal EKG We have an obligation as professionals to be medical detectives.

Historical factors not typical of Cardiac Chest Pain : Historical factors not typical of Cardiac Chest Pain Discomfort that comes and goes Discomfort that goes away with exertion Discomfort on one side of the chest but not substernal Sharp Pain Discomfort lasting only seconds Pleuritic Chest Pain ( with breathing) Discomfort with movement

Atypical Presentations do not rule out AMI : Atypical Presentations do not rule out AMI Treat the patient We can still treat a patient for AMI even if they fail to meet Cardiac Alert Criteria

Trying to make some J waves : Trying to make some J waves

What is Myocardial Infarction : What is Myocardial Infarction One of several syndromes Occlusion of a Coronary Artery by a clot, thrombus, Plaque, Air, or arterial Spasm that results in damage to the Myocardial tissue. One of many Ischemic Syndromes

Other Syndromes : Other Syndromes Silent MI Angina-Stable vs. Unstable Aneurysm Pericarditis AMI STEMI All related to the same Disease process but can present the same or different.

12 Lead as a Tool : 12 Lead as a Tool One of many tools in the kit Can rule in AMI but cannot rule out AMI 12 Lead is combined with the History and Exam to help us determine where the patient fits in the list of syndromes

Angina : Angina Stable- Signs and symptoms occur with predictability Unstable- Any change from previous stable pattern

Coronary Artery Spasm : Coronary Artery Spasm Can produce 100% occlusion with ST changes May show resolution after vasodilators like nitro or Morphine Obstruction from a thrombosis or clot will not

AMI : AMI May present similar to angina but frequently more intense May occur without exertion Associated with SOB, Nausea, Vomit, Pale Cool Moist skin, and EKG Changes Pain may be substernal radiating to Jaw or Left arm. Pain can present anywhere between the umbilicus and the Eyes

AMI Continued : AMI Continued May have diminished Cardiac output and Syncope Diminished mentation May be silent May have dysrhythmias or no EKG changes at all Sudden death in 40% of cases

AMI Continued : AMI Continued Result of complete occlusion to the affected artery Proximal occlusions will affect larger muscle mass Affected muscle is in jeopardy of necrosis Quantity of loss is dependant on sixe of the vessel and location of the infarct Loss of more than 40% generally results in cardiogenic shock or death

AMI Continued : AMI Continued During early stages EKG may remain negative Patients can have complete infarctions and never show changes (Diabetic Females)

Role of the 12 Lead : Role of the 12 Lead Rule in Elevation (STEMI) Serial 12 leads ( every 10-15 minutes) Ischemia Elevation May show onset as well as progression

Leads and Acquisition : Leads and Acquisition 4 electrodes on 4 appendages Imperative to get leads placed out on meaty portions of the arms or legs If placed on the cor of the body amplitude measurements are not accurate Dry skin or placement over bones cause unreadable baselines EKG must be a clean tracing

Bipolar Leads : Bipolar Leads I, II, III Negative lead enhances voltage Negative lead provides reference point for Positive lead Positive deflection indicates depolarization toward that lead

What do they see? : What do they see? I looks left lateral side II looks bottom or inferior aspect III looks bottom inferior but to the right

Unipolar Limb Leads : Unipolar Limb Leads aV leads-(augmented voltage) Monitor programmed to amplify voltage R, L, or F tells where the limb placement of the positive electrode lies Takes an average of the negative and neutral lead resulting in a positive terminal between the two

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Augmented Leads : Augmented Leads aVR- looks at upper right heart aVL-looks upper left lateral above lead I aVF- looks inferior bottom of heart between II and III

Precordial Leads : Precordial Leads True Chest Leads V-1 through V-6 No voltage augmentation due to proximity to the heart V-1 and V-2 Look at septum V-3 and V-4 look anterior or front of heart V-5 and V-6 look at low lateral below Lead one

Placement of Precordial leads : Placement of Precordial leads V-1 4th ICS right of sternum V-2 4th ICS left of sternum V-4 5th ICS mid clavicular V-3 between V-2 and V-4 V-5 5th ICS anterior axillary V-6 5th ICS mid axillary

Positioning and Preparation : Positioning and Preparation Lying down is ideal Fowlers or Semi fowlers is acceptable Shave excess hair Abrading area with skin tape Dry moist skin Have patient lie still.

Understanding the Printout : Understanding the Printout 4 sequential time frames I,II, III aVR, aVL, aVF V1, V2, V3 V4, V5, V6 P, QRS, T axis- very accurate Rate- very accurate Machine interpretation- very poor

Patterns and Indicators for AMI : Patterns and Indicators for AMI Good indicator for AMI Highly specific and 90% accurate Fast compared to enzyme studies Can be used to determine other associated risks-(hypertrophy, hemi blocks, block risk, BBB’s)

Limitations : Limitations Lack of sensitivity in endocardial or epicardial infarcts Cannot be used to rule out AMI Diabetics Females Machine must operate within a diagnostic range Ability of technician to accurately read EKG Some non-infarct patterns look like AMI

Triage : Triage ST Elevation or new Left BBB T wave inversion or ST depression Non diagnostic

ST Segment Elevation : ST Segment Elevation Indicates salvageable injury 1mm in frontal plane leads 2 mm in V leads Must be in two contiguous leads

ST Elevation continued : ST Elevation continued Indicates trans-mural injury (across 3 layers of the heart) Shape of the elevation is not as critical as the elevation it’s self Reciprocal changes are more important

ST Depression : ST Depression Not as reliable an indicator for AMI unless there is elevation in an opposite lead May be caused by AMI, ischemia, sub-endocardial injury, medications, or electrolyte changes SEE PROGRESSION SHEET

Inverted T Waves : Inverted T Waves Early Ischemia Reduction of blood flow May disappear as the area is reperfused post Nitro Nitro can be diagnostic as well as theraputic- 12 lead prior to nitro if possible Inverted T waves are normal in V-1, III, and aVR

Q Waves : Q Waves Injury left untreated may develop pathological Q waves Signifies death of tissue and is not reversible .4mm wide or 1/3 the size of the r R wave is significant

Location of the AMI : Location of the AMI Inferior-II, III, aVF Septal-V-1 and V-2 Anterior-V-3 and V-4 Lateral-V-5, V-6, aVL, I Right ventricular- V-4R Consider posterior with depression in V leads or run a V-7, V-8, V-9

Back when Wenkebach discovered his rhythm without the use of an EKG : Back when Wenkebach discovered his rhythm without the use of an EKG

Cardiac Alert Program : Cardiac Alert Program Decrease 911 to Cardiac Cath Get right patient to the right hospital for the right treatment Requires attention to history, presentation, and 12 lead MCR is destination for Cardiac Alerts Current average (2008) 53 minutes Paramedics have equal accuracy as ER Physicians SEE PROTOCOL HANDOUT C-9

TVEMS/Heart Center of the Rockies Criteria : TVEMS/Heart Center of the Rockies Criteria Does not reside in nursing home Does not have a DNR 35-50 years old Onset less than 12 hours Characteristic Cardiac presentation 12 Lead-1mm elevation in two or more contiguous frontal plane leads 12 Lead- 2 mm elevation in two or more V leads No LBBB or Paced rhythms

Contiguous Leads : Contiguous Leads An two V leads next to each other I and aVL II and aVF aVF and III V-6 and I

Treatment : Treatment O2 Nitro-what are the issues? MS-what are the issues? Fentanyl ASA-what are the issues? 2 IV’s Serial 12 leads if time permits Call Alert Tx dysrhythmias COR-zero’s go to closest hospital Consult MMC ER for borderline alerts, all others go to closest hospital of hospital of patients choice

STEMI STRIPS : STEMI STRIPS

OH NO! THE FEARED AXIS! : OH NO! THE FEARED AXIS!

HEXAXIAL SYSTEM : HEXAXIAL SYSTEM Uses frontal plane leads to determine direction of ventricular vectors Measured in degrees from zero (left lateral aspect at lead I Left or right, positive or negative

Determining Axis the hard way : Determining Axis the hard way Is lead one positive or negative? this puts the axis right or left. Is aVL positive or negative? This puts the axis upper or lower. Which lead is isoelectric? Axis is 90 degrees into the determined quadrant. Mind boggling I know!

Axis the easy Way!!! : Axis the easy Way!!! Find the tallest QRS complex in the frontal plane leads. This is the direction of the axis. Confirm that the deepest negative QRS is opposite this. Example: If II is the tallest aVR should be the deepest -----If III is the tallest then aVL or I should be the deepest.

Why determine Axis : Why determine Axis Essential if you look for hemi blocks Essential for determining Wide Beat Tachycardia origin

Types of axis : Types of axis Physiological Left Pathological Left Normal Right ERAD-Extreme Right Axis Deviation

Physiological-Minus 40 degrees or less : Physiological-Minus 40 degrees or less Not of concern Caused by physiologic situations Pregnancy Obesity Body shift Respiration Tumors III negative, I and II positive

Pathalogical-Minus 40 degrees or more : Pathalogical-Minus 40 degrees or more Left anterior hemi block Medication induces axis change-(tricyclics, phenothiazines) V-Tach Ectopy III, II, negative, I positive

Right Axis-Plus 90 degrees to Minus 100 degrees : Right Axis-Plus 90 degrees to Minus 100 degrees Normal in children Pathological in adults Posterior Hemi block RVH Cor Pumonale (right heart failure) PE V-Tach Tricyclic or phenothiazine OD ERAD-most likely ventricular

Hemi block : Hemi block Alone it is well tolerated and asymptomatic With AMI it has 4 times the mortality At high risk for developing Complete Heart Block With AMI can indicate Proximal occlusion LPH- Right axis with small R in I and small Q in III LAH-Left axis with small Q in I and small R in III

Bundle Branch Blocks : Bundle Branch Blocks Electrical occlusion of the right or left Bundle Left Bundle contains the fascicles Tri-fascicular system Disallows simultaneous depolarization of ventricles decreasing cardiac output Branches conduct 200 times faster than muscle tissue

BBB’s : BBB’s Need constant blood supply Conduction is lost and then occurs slower thru cardiac muscle cells Caused by ischemia, HTN, degenerative myocardial disease. Occur I identifiable patterns First one ventricle then the other contract out of sync May be rate dependent

Result of BBB : Result of BBB Ejection fraction drops What is ejection fraction? A measure of Left ventricular output measured as a fraction converted to a percent Normal is 60-75% Use of vasodilators with low fractions cause low BP

How to determine BBB : How to determine BBB Partial BBB QRS is .08 to .10 Complete BBB QRS is .11 or greater Use widest QRS on 12 lead to determine V-1 is used to determine if BBB is Right or Left Turn Signal criteria-Down in V-1 is left, Up in V-1 is right Must have a p wave associated unless a-fib is present

Other Criteria for BBB : Other Criteria for BBB Morphology-RBBB = rsR-initial r may be small Upward in V-1-right turn Clyde See Morphology sheet Morphology-LBBB = single downward complex, early nadir See Morphology sheet

Morphology Recognition : Morphology Recognition Knowing the hallmarks of BBB at normal rates is a key component determining the origin of Wide beat tachycardia's SEE MORPHOLOGY HANDOUT

BBB Significance : BBB Significance Permanent or temporary (rate dependent) Well tolerated in permanent states New or rate dependant onset may cause syncope, dizziness, hypotension. May not tolerate higher activity levels Serious in MI setting May indicate anterior wall damage At risk for complete heart block RBBB 4 times the mortality in MI Can develop V-Fib

BBB Continued : BBB Continued LBBB obscures ST segment making ST elevation AMI Difficult New LBBB should be considered AMI till proven otherwise (not included in Cardiac Alert however) ST segment in RBBB is intact and AMI can be detected

LBBB Facts : LBBB Facts Higher mortality than RBBB Common in Large Anterior AMI Lower ejection fractions ( < 50%)when greater than .17 Poor left ventricular function Higher mortality when not treated with fibrinolytic Associated with higher left ventricular end diastolic pressures

How do I Know if it is a New LBBB : How do I Know if it is a New LBBB You probably don’t! Need previous recent 12 lead to tell. If patient fits the AMI profile but has a LBBB we can alert the receiving facility, give our opinion, but they have to make the cath lab call. There are some experimental criteria out there for determining LBBB with AMI but it is inconclusive as of yet.

Mind you, moose bites can be very painful! : Mind you, moose bites can be very painful!

A Short Bit About Bi-fascicular Blocks : A Short Bit About Bi-fascicular Blocks RBBB and one of the two fascicles LBBB When a bi-fascicular black exist certain medications if given can cause complete heart block or asystole Lidocaine, Procainamide, Morphine, Digoxin, Beta Blockers, Calcium Channel blockers *DRAW ON BOARD

Significance of Blocks : Significance of Blocks Continuum of severity First Degree to Complete Blocks don’t have to be “Complete” to have significance-Hemiblocks and BBB’s have higher mortality when with AMI Consider this- Any time you use the word block twice when describing a rhythm the patient is at risk for complete heart block

Examples : Examples First Degree BLOCK with a BB BLOCK Left BBB- BLOCK of anterior and posterior (2) Hemi BLOCK and RBB BLOCK When this occurs we need to consider what medications we are giving and be prepared to treat complete heart block.

Wide Beat Tachycardia's : Wide Beat Tachycardia's STUDY 150 patients 122 had V tach 21 had SVT with wide complex 7 had WPW HOW MANY WERE DIAGNOSED CORRECTLY IN THE ACUTE CARE SETTING???

Thirty Nine : Thirty Nine Why is that???

Reasons : Reasons Clinitions assume that stable presentation rules out V-TACH This incorrect assumption is a pitfall to correct interpretation Perception that SVT occurs more often than V-TACH This incorrect perception is a pitfall as well Failure to perform a 12 lead due to excitement factor-People get excited when they think it is V-Tach

Why is misdiagnosing a problem? : Why is misdiagnosing a problem? Electricity fixes both rhythms! Amiodarone can fix both rhythms. Procainamide can fix both rhythms. So why does it matter?

Misdiagnosis issues : Misdiagnosis issues Some Medications can harm. Lidocaine, Procainamide. Not used as first line any more. Conversion with electricity or Amiodarone fixes the immediate problem but does not diagnose the rhythm specifically. This can cause reoccurring rhythm later because the patient may be put on the wrong prescription or none at all.

12 Lead as a diagnostic Tool : 12 Lead as a diagnostic Tool Use of the 12 lead in patients who are stable increases the chance for an accurate diagnosis of the rhythm If the mechanism of a rhythm is known the patient can get better care. I’m not advocating this for patients who are circling the drain, only those who are stable.

Differentiating : Differentiating Treat life threats first Differentiate when possible using History, 12 Lead, and physiological signs.

What are the criteria? : What are the criteria? We have talked about BBB morphology- it applies to tachycardia's as well-V-1 is Key Look at QS, QRS width Axis Morphology Concordance Fusion and capture beats Regularity Delta waves

V-TACH : V-TACH Regular > 140 bpm ERAD with a positive V-1 (100%) Right axis with negative V-1 Pathological left Axis Morphology-See chart RS > .04 QS > .07 QRS > .14if up, > .16 if down Concordance Fusion or Capture Beats Av Dissociation Cannon Waves (irregular)

SVT : SVT Regular or Irregular (what rhythms) Rate > 140 (70-80, 140-160, 280-320) Morphology- see chart Normal Axis (V-tach can’t have normal axis) Cannon waves History Associated P waves Delta waves

WIDE BEAT STRIPS : WIDE BEAT STRIPS

If you get divorced and keep your Corvette do not annoy the EX!!! : If you get divorced and keep your Corvette do not annoy the EX!!!

Now for the Obscure : Now for the Obscure Electrolytes- responsible for polarity and action potentials Potassium and Calcium have strong influences over cardiac cycle Significant imbalance can be seen on EKG

Potassium : Potassium Allows for organized fast rates Protects from excitability Slows heart during vagal influence

Hypokalemia-< 3.5mEq/L : Hypokalemia-< 3.5mEq/L Vomiting Diarrhea Diuretics ( non potassium sparing) Gastric suctioning- same as vomiting Hypomagnesemia Digitalis SEE HANDOUT

Hypo K+ Sigs and Symptoms : Hypo K+ Sigs and Symptoms Muscle weakness Polyuria Torsades Flutter Blocks Bradycardia ST depression Flat T waves with U waves that are larger Long QT and PR

Hypo K+ Treatment : Hypo K+ Treatment Cessation of vomiting, suction, diarrhea Potassium Drip

Hyperkalemia->5mEq/L : Hyperkalemia->5mEq/L Renal Failure Ketoacidosis Be ware of patients late for dialysis To Much K+ supplement

Signs and Symptoms : Signs and Symptoms VF Asystole Coma unknown cause- look for DKA and suspect –need to do a 12 lead Tall tented peaked T waves Widening QRS-irregular rhythm Broad S wave in V leads Left axis P waves flat or gone Sine waves SEE HANDOUT

Treatment : Treatment D-50 * Calcium * NAH2CO3 * Insulin Proventil

Calcium-4.5-5.5 mEq/L : Calcium-4.5-5.5 mEq/L Hypercalcemia-shortened QT interval Hypocalcemia-Long QT interval QT intervals are rate dependant SEE HANDOUT

Hypercalcemia Causes : Hypercalcemia Causes Hyperparathyroidism Metastatic Tumors of Bone Paget’s Disease Osteoporosis

Hypocalcemia : Hypocalcemia Hypoparathyroidism D deficiency Kidney Failure Pancreatitis Fluoride Poisening-Burns

Hypocalcemia tests : Hypocalcemia tests Chvostek’s Sign- Facial Nerve twitch when nerve is stimulated Trousseau’s Sign-BP cuff and arm twitching after a few minutes

Medications : Medications Quinidien, Amiodarone, Procainamide, Tricyclics, Disopyramide, Phenothiazines, Digitalis Can lengthen QT interval Can Cause Polymorphic V-Tach

Tricyclics : Tricyclics NAH2CO3-Displaces Drug out of Cardiac Cell

Digitalis Effect : Digitalis Effect ST depression or flattening of ST segments Scooped out ST segment (classic) Can cause blocks SEE HANDOUT

Parting Strip : Parting Strip SEE HANDOUT