Neonatal and Pediatric Guidelines for Arrhythmia ...

1 Neonatal andPediatric Guidelines for ArrhythmiaManagementWhat the Neonatal and Pediatric Critical Care Nurse Needs to KnowCecilia St. George-Hyslop,M Ed,RN, CNCCP(C), The Hospital for Sick Children, Toronto,CanadaCandace Morton, MSN, CPNP-PC/AC, Children s Hospital of WisconsinElizabeth Daley,BA,BSN,RN,CCRN, Children s Hospital of Los AngelesIntroduction to the Problem:Arrhythmias are relatively common in the Pediatric cardiac intensive care unit. Grosse-Wortmann et al studied 494patients revealing 59% of neonates and 79% of older children have arrhythmias within 24 hrs of surgery.

2 Of thesearrhythmias, junctional ectopic tachycardia (JET) was seen in 9% of neonates and 5% of older children. Ventriculartachycardia was found in3% of neonates and 15% of older children (Gross-Wortmann, 2010).In terms of specific arrhythmias, sinus tachycardia is the most frequently seen Arrhythmia , with supraventriculartachycardia being the next most common, followed by sinus bradycardia (Hanash, 2010). Reentrant tachycardia iscommon in infants and children with congenital heart disease (CHD).Some arrhythmias in the early post operativeperiod like premature atrial contraction s (PAC s) and premature ventricular beats (bigeminy) are usually transientand well tolerated.

3 Others like junctional ectopic tachycardia (JET) and atrial flutter may cause significanthemodynamic instability and compromise or even sudden cardiac arrhythmias occur in children without structural heart disease, although they may be secondary to ionchannel diseases that are still being factors that predispose children for secondary arrhythmiasincludecongenital cardiac malformations, surgical repair and scarring,long cardiopulmonary bypass times, orexposure to chronic hemodynamic stress (Brugada, 2013). Electrolyteand acid-baseimbalanceand the use ofvasoactive drugsalso predispose children to arrhythmias(Jhang, 2010).

4 Inflammation/carditis seen in diseases suchas acquired heart diseases like Kawasaki disease, rheumatic fever and myocarditis mayproduce arrhythmogenic foci(Curley, 2001). Conditions of ventricular volume overloading, valvular regurgitation, congestive heart failure andpulmonary hypertension are other secondary reasons (Huh, 2010).Regardless of the cause of the Arrhythmia , thereare certain common signs, symptoms and treatment options that are ultimately based on the rhythm more than on theetiology with certain very important may vary depending upon age and include feedingintolerance, lethargy, irritability, pallor, diaphoresis, syncope, fatigue or of tachyarrhythmias can be enhanced automaticity with triggered foci or enhanced conduction with thepresence of reentrant circuits.

5 Similarly bradycardia can result from suppressedautomaticity or suppressedconduction, where normal conduction is delayed or blocked (Allen, 2011). Understanding the mechanism informsthe optimal treatment review will describe the variety of arrhythmias that occur in Pediatric patients, how they are characterized,andtheassociations with congenital heart disease, cardiomyopathies and ion channel diseases. Clinical manifestations,etiologic considerations, diagnostic measuresand treatment strategies will be Consider/Address:CARDIACARRHYTHMIACHARAC TERISTICSSick sinussyndrome (SSS)/Tachy-BradySyndromeSinoatrial(SA)n odebecomesdysfunctionaland isno longer a reliable pacemaker, mostcommonly manifested as bradycardia, although there can alsobe tachycardia.

6 When thesinus rate is slower than another potential pacemaker in the heart, it may no longer be thedominant pacemaker. SSS can also cause an alternating bradycardia and number of rhythms result includingsinusbradycardia, sinus arrest and junctional rhythm,andectopic atrial and term SSS includesSA node dysfunction plus symptoms ofdizziness,syncopeor suddencardiac death(Park, 2010).BradycardiasOften caused byhypoxia,vagaltone, hypothyroidism, cardiac surgery,endocarditis andmyocarditis(Hanash, 2010); hyperkalemia, sleep, hypothermia, sedation and anesthesia.

7 (Curley, 2001).Sinus bradycardia:Sinus node slower than normal for age related normal junctional escape rhythm/nodal rhythm:Spontaneous depolarization of the AV sinus node has either failed to fire or is slower than the AV 50-80 beats/mininchildrenlessthan 3 yrsand 40-60 beats/min for children older than 3yrs. Can be commonafter atrial surgery and are usually escape rhythm or ideoventricular rhythm:Origin of impulse is from the ventricleand presents with rates slower than from the AV node. QRS have wide complexmorphology. This primary Arrhythmia and occurs when thesinus node and/or the AV nodeare dysfunctional.

8 An example of this iscomplete heart blockwith a ventricular escape rhythm. The ventricleitself is working well, and the escape rhythmisa symptom of another atrial, junctional and ventricular ectopic beatsare common and may occur inpatterns of bigeminy, trigeminy, quadrageminy are generally AtrialPacemakerShifting of the pacemaker site from the SA node to alternate sites in theatria and junction(AV node). P-wave configuration changesas the site (SVT)SVT is used as acollective abovethe bundle of circuits generally have an abrupt onset andtermination are paroxysmal(Hanash, 2010).

9 Sinus tachycardia:Sinus nodeisfaster than age-related normal values due to due to fever, pain,anxiety, anemia, medications, hypovolemia or in thepresence of increased catecholamines. While not generally an indication of conductionsystem pathology, sinus tachycardia may be an important indicator of significantcardiovascular tachycardias:Reentrant tachyarrhythmias require the presence of two possibleconduction pathways with different conduction and refractory properties. The tachycardiauses both pathways; one as an antegrade limb and one as a retrograde limb of the )Within the atria: atrial flutter, atrial fibrillation; intra-atrial reentrant tachycardia(IART)atrial flutter-or incisional tachycardia represents macroreentry within theatrial muscleand may be slower than atrial flutter(Walsh 2007).

10 B)Atrioventricular reentrant tachycardias include:1)atrioventricular reentrant tachycardia (AVRT): commonly associated with Wolff-Parkinson-White. Accessory pathway present allowing impulses thatentered viathe AV node to enterthe atria2)atrioventricular nodal reentry tachycardia (AVNRT):uses a slow-fastAV nodalpathway .Antegradeconduction limbis the slow pathway and retrograde limbfast of the atria by the retrograde pathway produces inverted p-wavesif of the )permanent junctional reciprocating tachyarrhythmia (PJRT). These arereentrantcircuits in which one limbincludes the AV Syndrome (WPW):Baseline resting ECG is characterized by a shortPR interval, wide QRS and delta wave which is a manifestation of the accessory on is marked by the delta wave on therestingECG(Allen, 2001).