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Technical Tips The Journal of Emergency Medicine, Vol. 32, No. 1, pp. 105–111, 2007 Copyright © 2007 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/07 $–see front matter doi:10.1016/j.jemermed.2006.05.037 Technical Tips TEMPORARY TRANSVENOUS PACEMAKER PLACEMENT IN THE EMERGENCY DEPARTMENT Richard A. Harrigan, MD,* Theodore C. Chan, MD,† Steven Moonblatt, MD,* Gary M. Vilke, MD,† and Jacob W. Ufberg, MD* *Department of Emergency Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania, and †Department of Emergency Medicine, University of California, San Diego Medical Center, San Diego, California e Abstract—Emergency Department placement of a tem- patient management in the ED—depending upon patient porary transvenous cardiac pacemaker offers potential life- stability—placement of a transvenous cardiac pacemaker saving benefits, as the device can definitively control heart (TVP) usually is performed after other less invasive rate, ensure effective myocardial contractility, and provide means of treatment (e.g., pharmacologic, treating the adequate cardiac output in select circumstances. The pro- cedure begins with establishment of central venous access, underlying cause, transcutaneous pacing) have been ex- usually by a right internal jugular or left subclavian vein plored and exhausted. approach, although the femoral vein is an acceptable alter- Although a variety of pacemaker modalities exist— native, especially in patients who are more likely to bleed transesophageal, epicardial, endocardial, transcutaneous, should vascular access become complicated. The indica- and transvenous—it is the latter two methods that have tions for the procedure, as well as the equipment needed, applicability in the ED. Transcutaneous pacing, which is are reviewed. Both blind and ECG-guided techniques of usually employed initially as a temporizing measure, will insertion are described. Methods of verification of pace- not be discussed here. Transvenous pacing, which involves maker placement and function are discussed, as are the placing a catheter-based electrode into the right side of the early complications of the procedure. © 2007 Elsevier Inc. heart, is actually two procedures in one: establishing central e Keywords—transvenous pacemaker; cardiac pacemaker; venous access, and then introducing and directing the elec- cardiac procedures trode through the venous system into the heart. Placement of a TVP involves placement of the electrode into the right ventricle with the goal of pacing the endocardium in a VVI INTRODUCTION mode (Ventricle-paced, Ventricle-sensed, Inhibited sensing response). This is the least complicated approach to rees- Temporary cardiac pacing may be instituted in the Emer- tablishing effective cardiac depolarization, and it allows the gency Department (ED) for a variety of indications via physician to pace the heart either asynchronously or in a several different modalities. The goal of temporary car- demand mode, wherein the pacemaker is inhibited when a diac pacing is to restore effective cardiac depolarization native impulse is sensed. and myocardial contraction, resulting in the delivery of This review will focus on the indications for TVP adequate cardiac output. Whereas consideration of tem- placement and describe the two common ways the pro- porary cardiac pacing may begin early in the course of cedure may be performed in the ED—blindly and with Technical Tips is coordinated by Gary M. Vilke, MD, of the University of California, San Diego, San Diego, California and Richard A. Harrigan, MD, and Jacob W. Ufberg, MD, of Temple University, Philadelphia, Pennsylvania RECEIVED: 20 October 2004; FINAL SUBMISSION RECEIVED: 3 November 2005; ACCEPTED: 31 May 2006 105 106 R. A. Harrigan et al. Table 1. Indications for Emergent Transvenous Pacemaker generator. In addition, an ECG machine and cardiac Placement (1–3)* monitor should be available. Several pre-packaged trays Bradydysrhythmias are available that contain the introducer sheath, pacing Symptomatic sinus node dysfunction catheter, and other equipment necessary for pacemaker Sinus arrest Sinus bradycardia insertion. Symptomatic atrioventricular block The external pacing generator is used to deliver the Second degree atrioventricular block, Mobitz type II electrical current, measured in milliamperes (mA), Third degree (complete) atrioventricular block Symptomatic drug overdose through the pacing catheter. Various available generators Tachydysrhythmias share the same basic features (Figure 1). The pacing Overdrive pacing of rhythms refractory to medical generator has electrical output and cardiac sensing com- management ponents, which are usually present as dials on the face of * The indications are listed with the assumption that: 1) less invasive the generator. An output control dial allows for regula- means (e.g., pharmacologic agents and antidotes, transcutaneous tion of the current, usually from 0.1 to 20 mA. This cardiac pacing) have been tried without success or that success is judged to be short-lived; or 2) the patient is experiencing principally determines the ability of the pacemaker to profound symptomatology (e.g., severe chest pain, dyspnea, or “capture” the heart. A rate control dial selects the pacing altered state of consciousness; hypotension; shock; pulmonary rate. The pacing generator also has a sensitivity control edema; or acute myocardial infarction). that establishes a threshold, based on the amplitude of the native R wave, required to suppress the pacemaker from firing. Turning the sensitivity control down will lead to electrocardiographic (ECG) guidance. Confirmation of fixed rate, or asynchronous, pacing, wherein the pace- placement and function will be discussed, and commonly maker fires regardless of the patient’s underlying rhythm. encountered complications will be reviewed. Increasing the sensitivity in concert with modifying the rate control will eventually lead to demand, or synchro- INDICATIONS AND CONTRAINDICATIONS nous, pacing. This occurs when the pacing generator senses intrinsic cardiac activity and inhibits the TVP Various authorities differ slightly when defining the in- from firing. In demand mode, the pacemaker senses the dications for placement of a TVP (1–3). Indications can patient’s underlying ventricular rate and will not fire as be viewed with several constructs in mind: emergency long as the patient’s rate is equal to or faster than the rate vs. prophylactic pacemaker placement; treatment of bra- set on the pacing generator (2,3). dydysrhythmias vs. tachydysrhythmias; and in patients Various transvenous pacing catheters are available experiencing acute myocardial infarction vs. those who with basic similarities. Most are bipolar, 3 Fr to 5 Fr in are not. Table 1 lists standard emergent indications for size, and approximately 100 cm in length (3). Lines TVP placement, and Table 2 depicts commonly accepted marked at 10-cm intervals on the catheter surface can be prophylactic indications for the procedure. In most emer- used to estimate catheter position. Catheters are classi- gent circumstances, a transcutaneous pacemaker is uti- fied as flexible, semifloating, or rigid/non-floating cath- lized initially while the patient is prepared for TVP eters. The latter group carries a higher risk of cardiac placement. Transvenous pacing, and in fact pacing in perforation, and thus they are generally used only under general, does not seem to be beneficial in asystolic/ fluoroscopic guidance, where their stiffness yields the bradyasystolic cardiac arrest, traumatic cardiac arrest, or benefit of easier manipulation (1). In emergency situa- in patients with profound hypothermia and bradydys- tions, a semifloating catheter with or without a balloon rhythmias (3,4). In the latter group, aggressive treatment tip is used most commonly (1–3). In the patient in of the underlying condition is paramount, due to the cardiac arrest, inflating the balloon carries no benefit, as theoretic concern that introducing a pacing wire into a hypothermic patient may precipitate terminal dysrhyth- mias. However, in-hospital cardiac arrest victims with Table 2. Indications for Prophylactic Transvenous complete heart block or bradycardia (not those with Pacemaker Placement (1–3) asystole) may receive some benefit from transvenous Acute myocardial infarction (especially anterior distribution) pacing unresponsive to pharmacotherapy (5). and Symptomatic sinus node dysfunction Second degree atrioventricular block, Mobitz type II Third degree atrioventricular block EQUIPMENT New left, right, or alternating bundle branch block New bifascicular block The equipment needed to insert a TVP includes an in- Symptomatic patient secondary to failure of permanent pacemaker troducer sheath, pacing catheter, and external pacing Temporary Transvenous Pacemaker 107 there is no forward flow of blood to guide an inflated balloon through the venous system into the right side of the heart. The balloon holds approximately 1.5 cc of air and should be tested for air leak before insertion. At the leading end of the catheter are two electrodes, one of which is marked negative and lies distally. Adapters are supplied in the kit to allow the electrodes to be attached to the pacing generator or to an ECG lead (Figure 2). The introducer sheath is used to establish central venous access. The sheath allows for passage of the pacing catheter into the vein and must be at least one size larger than the pacing catheter. Some sheaths will con- tain an additional port for administration of intravenous
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