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Staff Sergeant
Join Date: Mar 2011
Posts: 95
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should be regarded as critical
should know before reading a few basic questions:
1, the significance of the wave
(1) P wave: represents atrial depolarization process: it is P wave abnormalities often represent the heart of the problem, such as a COPD patient lead II P wave amplitude> 0.25mv, diagnosed right atrial hypertrophy.
(2) PR interval: not equal to the PR segment, while = P wave + PR segment. Representative of the beginning of atrial depolarization to the beginning of ventricular depolarization, so the time extension can be seen in atrioventricular block.
(3) QRS wave group: the whole process of ventricular depolarization. Normal QRS wave group were all there for gambling, if there wide QRS wave group deformity, often on behalf of ventricular problems. If PVCs showed early appearance of large abnormal QRS wave, and as a room early, as long as no bad room with Biography, QRS morphology is normal. The heart is pumping by the ventricle, and QRS wave is the performance of ventricular activity, heart problems will not immediately any death, but the ventricle will, even if an abnormal ECG QRS wave can not be found, indicating that the heartbeat has stopped.
(4) ST-T: the whole process of ventricular repolarization: it is the abnormal rise as cardiac problems. The clinical status of high, but its poor specificity change.
(5) QT interval: the whole process of ventricular activity. Mainly depends on the QTc interval, that is, corrected QT interval, QT interval for heart rate will slow long as the heart rate under a variety of comparable QT interval, it produces QTc interval [= QT interval / (root No. RR)], where RR units of S, usually played only by watching the computer or look-up table access, or by feeling), QTc interval is a meaningful value.
2, as a non-ECG specialists, from the physiology of the principle of up ECG, the result set is a lose, nothing. Clinicians to understand as long as this is what map is not in critical danger, is enough.
3, the two ECG Precautions:
(1) an ECG has several diagnoses, there is a certain order of stress, has not found a clear standard, but certainly the first to write a certain rhythm places, such as sinus rhythm, atrial rhythm, atrial fibrillation, and left axis deviation to write the second, other standards available.
(2) ECG diagnosis is divided into three categories:
① A class: multi-finger anatomy, pathophysiology, diagnosis: There are various atrioventricular hypertrophy, myocardial infarction, ischemia, coronary insufficiency, such as the electrolyte imbalance and must rely on clinical data. For example, an abnormal Q wave + ST segment elevation + T arched-type wave changes typical of myocardial infarction ECG, chest pain, chest tightness and other patients with no history of myocardial infarction is usually not diagnosed, ECG report can mean to write: abnormal Q wave , ST-T changes, please combined with clinical, but the report of the surgeon was able to understand it? If the responsible thing, you can write to consider acute myocardial infarction possible, clinical; ECG alone is not qualified to direct that the general MI (Physiological and pathological diagnosis). Another example of a left ventricular high voltage ECG, if induced left ventricular hypertension or other major medical history, can be directly diagnosed voltage And so on.
② B class: just look at a history of ECG can not be directly diagnosed, various types of arrhythmia is the main force, such as atrial fibrillation, WPW syndrome, third degree atrioventricular block, a look at figure can not be any medical history.
③ In addition to the two other cases outside, such as ST-T changes, such as heart clockwise translocation, such as left axis deviation.
4, Figure way:
for critically ill patients, must be seen immediately asked to see a major problem, first ignore the other minor problems; and general pictures and requirements from start to finish, from P wave to T wave one to read and time, amplitude, shape without exception, I lead from the V6 lead left out to look. It must be used in normal prison back to talk about Figure.
fact, the most important fact to be firmly back on a few: P wave time should be 200, note if the various types of AV block, if 200ms was used to determine whether complete or incomplete bundle branch block. There QTc interval, normal is 500ms, depending on whether QT interval prolongation syndrome, electrolyte disorders.
II electrocardiogram
clinicians understand critical look at critical ECG is a priority! Each Branch has its own not to do an ECG, but each section can be determined to electronic monitoring machine, in particular, the surgeon must pay attention to it! When the doctors did not face a culture of critically ill patients on continuous ECG monitoring of ventricular tachycardia but does not know, but pretend to solemnly analyze the content of the ECG, you immediately take off the white wolf, clothing, speech from medicine to avoid harm to men! But you read this, you can continue to be a doctor.
clinical findings, I believe that the following five major categories critical ECG:
A: [Acute myocardial infarction]
for high-risk factors (such as the elderly, coronary heart disease, hypertension, DM, high cholesterol, etc. ) of the patients can not be explained by other causes of chest tightness / chest pain / palpitations / upper abdominal pain and / or ECG left shoulder and back pain should check to identify acute myocardial infarction. Clinical diagnosis of acute myocardial infarction
rely mainly on three criteria: (1) The duration of symptoms, in particular the continuous severe chest pain (2) ECG changes with myocardial infarction and dynamic performance (3) increased myocardial necrosis markers.
mainly refers to myocardial necrosis markers troponin (+ Search of a ¥ 300 Mb or so), high specificity, as long as high, basically determine myocardial necrosis (myocardial infarction, but not 100% is due to necrosis, which can be myocardial injury caused by other reasons such as heart damage interventional procedures, such as unstable angina can trace increased> 3 times the normal meaning more definite myocardial infarction), myoglobin, CKMB also valuable, but not as muscle-specific calcium; other enzymes such as CK, LDH poor specificity, only for reference. In addition, there needs time markers, 2 hours or more range, and sometimes muscle calcium may not appear low, note review.
they meet two of the three conditions, the basic clinical diagnosis of acute myocardial infarction. Clinicians need to know, in fact, the value of ECG diagnosis of myocardial infarction is limited, since some only (1) + (3) the performance of the ECG in patients without obvious change, CAG (coronary angiography) that he is serious coronary artery disease or even a branch occlusion, myocardial infarction, very serious. Therefore, do not easily diagnosed by ECG or exclude acute myocardial infarction. Clinical will be divided into
ST-segment elevation myocardial infarction myocardial infarction (STEMI) and non-ST segment elevation myocardial infarction (NSTEMI), because the clinical most common cause of cardiogenic shock, acute pulmonary edema, death MI is mainly typical ECG STEMI, where they talk about it.
typical acute myocardial infarction ECG: (1) pathological Q wave (2) ST segment elevation was particularly arched type (3) T wave changes (inverted or fused into one-way curve ST). If there is such a typical ECG, and is adjacent to two or more lead there, and my heart (heart only) can be thought: the patient had acute myocardial infarction get away. And obviously, if only ST-elevation myocardial infarction may have to pay attention, may be more early pathological Q does not appear to be dynamic investigation ECG. But if only two or more adjacent pathological Q and non-ST-T changes, generally considered to be old myocardial infarction.
pathological Q wave (abnormal Q wave):
(1) time> = 0.04S
(2) amplitude> = 1/4R with the guided wave. In addition to lead aVR, and III, as long as that met one, it is the pathological Q!
should be noted that: (1) III, aVR and V1 can be so normal, but in fact the aVR often is QS.
; (2) Some common clinical rS map and QS waves somewhat difficult to distinguish, especially when the interferences are generally only a little sharp in front of the r wave, we say it is a small r's, that it temporarily is a pathological Q, difficult to distinguish when the ST segment mainly to see if there is no elevation, is not a critical ECG, up to old myocardial infarction.
; (3) and another standard (not diagnostics) that: time> = 0.03S, amplitude> = 1mm, Q wave on a notch, shall meet one of the pathological Q.
myocardial infarction has important clinical significance of positioning: (1) The location, extent of myocardial infarction and prognosis of different critical level (2) diagnosis of myocardial infarction we usually can not just write level, the right should be
But what students read Does not matter, now you can understand. If
see
fact, most of the myocardial infarction clinical sites are: (1) extensive anterior wall (left anterior descending artery blood supply) (2) inferior wall (right coronary or circumflex artery blood supply) (3) anterior wall (left anterior descending branch blood) (4) anteroseptal (left anterior descending artery blood supply).
upper left involving six-axis system, beginners do not need to know why this painting, as long as the reading on the line. Icon: II, III, aVF most by the following, so when a performance of the three guide for inferior myocardial infarction.
bottom left us to do ECG involved in the site. As long as the body surface according to the position of lead can be judged. Figure: V1-V5 are present in front of the thorax, so the performance there is extensive anterior wall myocardial infarction; if only the V3-V5 is the anterior; Accordingly, if the V7-V9 (ECG done in the background when the site) , it is the posterior wall myocardial infarction; V1 if more right-hand number is the 18 leads in the right ventricle, so the V1, V2, V3 is the interval between the left and right room, if its a performance, it is the heart before the partitions stems. We will lead in the 18's called the posterior wall of the V7-V9, V3R-V6R will be known as the right room, so if V3R-V6R a performance (the normal right ventricle can have Q waves, mainly to see whether there was significantly elevated ST segment) When is the right ventricular myocardial infarction.
most prone to clinical cardiogenic shock, death is extensive anterior wall myocardial infarction. Clinical also common with inferior wall + extensive anterior wall infarction, which can often occur with cardiogenic shock (the most serious type of acute heart failure).
In addition, as long as myocardial infarction should be routine investigation of 18 guide. And vascular anatomy related to right ventricular or posterior infarction pure rare, as is mostly the other wall infarction had to appear while the right wall or posterior wall infarction, of course, there are simply right ventricle, the right wall Terrier. If it is found multi-walled stems, may be even worse prognosis.
experiencing acute myocardial infarction clear, the surgeon naturally urgent consultation within your heart; and physician consultation in addition you should also understand, whether to emergency PCI or thrombolysis or conservative, should immediately give thanks to aspirin 300mg + Bo Li 300mg oral dimension. Many, if not handled with acute myocardial infarction, cardiogenic shock will be death or malignant arrhythmia.
The picture above shows a typical ECG of acute extensive anterior wall myocardial infarction; next picture shows the old inferior myocardial infarction.
B: [seriously fast arrhythmia]
cardiovascular, respiratory disease foundation, regardless of any arrhythmia, ventricular rate as long as the state of calm soon (160 ah 170 ah , 180 ah or more) should be considered critical of the ECG, if heart palpitations (rapid heart rate are generally obvious), chest pain, shortness of breath and other symptoms, are more serious and required emergency treatment, ventricular rate control. Up to the dragon (amiodarone) is the ace of tachyarrhythmia treatment with broad-spectrum anti-arrhythmic effect, but nothing not to use, it is not very safe.
(a) of ventricular tachycardia required before VT
see ventricular premature know, know how to talk about ventricular tachycardia after ventricular premature, because the room rate for three or more consecutive ventricular premature. Besides white point, that is three or more consecutive abnormal QRS wave of the large group.
VT's scary to worsen as the room in its flutter, ventricular fibrillation trend. In particular, sustained ventricular tachycardia (lasting more than 30S).
large abnormal QRS on the map when there are no P waves, so the diagnosis of paroxysmal ventricular tachycardia, if P wave (or the fusion of pre-ordered increase in T wave), atrial tachycardia should be considered with the indoor missions.
ventricular tachycardia often keep up with the indoor housing as early as differences in transmission (the latter is often not critical) identification. Sometimes difficult to identify, would rather when it is to actively deal with VT.
asymptomatic paroxysmal ventricular tachycardia who had not urgently addressed, could be up to the dragon oral 0.2Tid, mainly search for a cause (often coronary heart disease) treatment.
if asymptomatic sustained ventricular tachycardia can be up to the dragon 300mg +5% GS50ml micro pump, if angina, edema, swelling, low blood pressure, synchronized cardioversion should be 100J. Pulseless ventricular tachycardia with ventricular fibrillation, electrical defibrillation directly 360J.
(b) supraventricular tachycardia
ECG say , treatment the same. Room, that is above the conduction of ventricular impulses, where the room rate does not include the sinus. Therefore, supraventricular tachycardia or atrial tachycardia is one of the junction of speed.
neat if the absolute heart rate, heart rate> 160 supraventricular tachycardia should be considered possible, if not find significant sinus P wave, which can be diagnosed; if also found atrial P wave, it should be quite able to atrial tachycardia clear. Ventricular rate in supraventricular tachycardia up to 180 or even 200 times over, most patients will have heart palpitations performance.
it with 2:1 conduction (?) of atrial flutter is often difficult to identify, but there is no relationship, emergency treatment is to use micro-pump up the dragon ventricular rate control, and other causes of treatment, ah, ah is something for catheter ablation. Sometimes identify with sinus tachycardia, sinus tachycardia, but very few heart rate of 160 or more.
(c) of atrial fibrillation with rapid ventricular rate in the diagnosis of atrial fibrillation
too simple, do not do ECG, feeling the pulse or heart auscultation can diagnose the majority of atrial fibrillation. Specific diagnostic criteria and typical chapter has described the primary atrial fibrillation. F waves have different patterns of atrial fibrillation is people will see. However, no significant clinical common
f wave, baseline AF base is flat, tender look at the birds may not understand. (Below)
teach a simple approach, in fact, as long as ventricular rate not met the rules, and each of the major differences between RR, basically 80% can be considered to be atrial fibrillation, and if looking for Less than sinus P waves, which can be diagnosed atrial fibrillation, do not have possession of various shapes without the so-called f waves.
another, generally considered: the ventricular rate in atrial fibrillation is absolutely irregular; the general: the rules of ventricular rate in atrial fibrillation is not. (But such as atrial fibrillation with atrioventricular block third degree or some other rate rules ventricular arrhythmias)
atrial fibrillation with rapid ventricular rate is often, if> 150, should be regarded as critical, the harm is: (1) is not synchronized atrioventricular contraction, ejection and afterload reduction of the increase, and even there may be angina, congestive heart failure; (2) easy to cause the formation of thrombus embolization.
if heart failure nor taboo cedilanid 0.3mg + NS20ml slow push is the preferred, if not also add up to the dragon or micro pump infusion, satisfactory ventricular rate is below 80. Aspects of anti-thrombosis preferred no contraindications warfarin, but one day one day late with no impact, not a range of emergency treatment.
C: [the vicious death quickly ECG]
(a) ventricular fibrillation and ventricular flutter
did not want to say, but when asked a clinical interns actually do not know, I feel the need to provide easiest to see what the most serious arrhythmia.
= ventricular fibrillation cardiac arrest. Ventricular fibrillation occurred / room flutter, generally patients have been breathing and heartbeat stopped.
ECG monitoring machine to see this, directly to give 300J defibrillation; or do not know if the unconditional, immediate cardiac massage, treatment.
I think that, in addition to the general situation is still kind of good, unexpected ventricular fibrillation may help to get back (to the heart more than medical patients, when rescued Cardiology), other patients generally can not be saved back out.
(b) the type of ventricular tachycardia torsade
attention to QTc interval prolongation must be like on the map as considered as abnormal ventricular tachycardia torsades de pointes type ventricular tachycardia.
its easily into ventricular fibrillation.
magnesium sulfate 2g +5% GS40ml slow iv then 8mg/min ivdrip.
(c) Pre-excitation syndrome, atrial fibrillation with rapid ventricular rate
pre-excitation syndrome sounds of distant birds and tender, but clinical is not uncommon, mainly to understand what is said.
(1) PR during the <120ms (normal is 120-200) (2) QRS beginning part of blunt (professional point called delta waves).
can meet these two basic pre-excitation syndrome was diagnosed; if secondary ST-T changes, certainly. As shown above, in fact, read a second to understand. Understand even more the level of type: V1 up to the main wave of QRS-A, down for the B type.
If asymptomatic, no tachycardia episodes, no treatment; but its onset of tachycardia may be atrial fibrillation, once the attack, the consequences could be very serious, such as atrial fibrillation, the graphics are terrible (below) , and unless there is ECG when compared with asymptomatic before, or may be difficult to diagnose. Like the following figure, without a history of pre-excitation syndrome, I think the level of non-specialist can not properly diagnose the map looks like ventricular tachycardia.
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