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Temporary Pacemaker Insertion

95

 

Rajesh Chawla and Vipul Roy

 

A 70-year-old male patient—a case of coronary artery disease on regular treatment—was admitted to the hospital with chief complaints of syncope and giddiness. His heart rate was 38/min and blood pressure was 90/60 mmHg. ECG showed complete heart block. Insertion of temporary pacemaker was planned.

Pacemakers provide electrical stimuli which cause cardiac contraction when the intrinsic myocardial electrical activity is slow or absent. Temporary pacemakers use an external pulse generator with leads placed either transcutaneously or transvenously. During emergency resuscitation, transcutaneous leads are the easiest and most convenient method of choice. Transcutaneous pacing requires mild sedation. For transvenous pacing, a semirigid catheter is placed through central access. ECG monitoring is used for tracking catheter positioning.

Step 1: Assess the need for the temporary pacemaker (Tables 95.1 and 95.2)

Step 2: Be familiar with the device (Table 95.3)

R. Chawla, M.D., F.C.C.M. (*)

Department of Respiratory, Critical Care & Sleep Medicine, Indraprastha Apollo Hospitals, New Delhi, India

e-mail: drchawla@hotmail.com

V. Roy, M.D., D.M.

Department of Cardiology, Indraprastha Apollo Hospitals, New Delhi, India

R. Chawla and S. Todi (eds.), ICU Protocols: A stepwise approach,

761

DOI 10.1007/978-81-322-0535-7_95, © Springer India 2012

 

762

R. Chawla and V. Roy

 

 

Table 95.1 Indications of temporary pacing in the absence of acute myocardial infarction

1. Symptomatic bradycardia refractory to medical treatment

(a)Sinus node dysfunction

(b)Secondor third-degree atrioventricular (AV) block

2. Third-degree AV block with wide QRS escape or ventricular rate <40 bpm

3. Prophylactic

Table 95.2 Indications of temporary pacing in acute myocardial infarction

Class I

1. Asystole

2. Symptomatic bradycardia (includes sinus bradycardia with hypotension and type I seconddegree AV block with hypotension not responsive to atropine)

3. Bilateral bundle-branch block [BBB; alternating BBB or right BBB (RBBB) with alternating left anterior fascicular block (LAFB)/left posterior fascicular block (LPFB)] (any age)

4. New bundle-branch block with Mobitz II second-degree AV block

5. RBBB plus fascicular block with Mobitz II second-degree AV block

Class IIa

1. Narrow QRS plus Mobitz II second-degree AV block

2. Old or new fascicular block with Mobitz II second-degree AV block and anterior myocardial infarction

3. Old bundle-branch block and Mobitz II second-degree AV block

4. New bundle-branch block plus first-degree AV block

5. New bundle-branch block plus Mobitz I second-degree AV block

6. RBBB plus LAFB or LPFB (new or indeterminate) with first-degree AV block

7. RBBB plus LAFB or LPFB (new or indeterminate) with Mobitz I second-degree AV block

Step 3: Transvenous pacemaker—procedure

A.Obtain a central venous access

1.The preferred route: Internal jugular (most common and most preferred), subclavian, and femoral veins, preferably right-sided veins, should be used when possible. Local anesthesia is always indicated.

2.Access blind or ultrasound-guided intracardiac placement of the pacing wire.

B.Intracardiac placement of the pacing wire

1.This should only be inserted by experienced practitioners.

2.Preparation:

(a)A defibrillator and other resuscitation equipments should be immediately accessible.

(b)Strict aseptic technique.

(c)ECG monitoring.

3. Cannulate the suitable vein (internal jugular, subclavian, or femoral veins preferably on the right side) using Seldinger’s technique of guidewire and dilators to place a sheath of the correct size.

4. Bend the tip of the electrode to give a 20–30° curve for the correct positioning in the heart.

Table 95.3 Temporary pacemaker method and device details

 

 

 

Device

Parts

Current

Benefits

Drawback

Uses

Transcutaneous

1. External patch

Higher current (up to

1. Less time-consuming

Require sedation

1. Cardiac arrest

external

electrodes

200 mA) and longer

 

 

 

pacemakers

2. Pulse generator

pulse duration

2. Risks of central

Pacing limited to

2. Symptomatic

 

(usually a

(20–40 ms)

venous access

ventricle and minimal

bradyarrhythmia

 

defibrillator)

 

avoided

capacity for atrial

3. Overdrive pacing

 

 

 

 

pacing

4. Prophylactically for

 

 

 

 

 

 

 

 

 

 

arrhythmia in myocardial

 

 

 

 

 

infarction

 

 

 

 

 

5. Unavailability or contrain-

 

 

 

 

 

dication to transvenous

 

 

 

 

 

pacing (prehospital setting

 

 

 

 

 

during thrombolytic therapy

 

 

 

 

 

for acute myocardial

 

 

 

 

 

infarction)

Transvenous

1. Transvenous pacing

Threshold for vent.

Different modes

Inherent risk with

Indications as per Table 95.1

pacing

catheters (4–7 F)

 

(ventricular, arterial,

central venous line

 

 

2. Pulse generator

Pacing (<1 mA), atrial

sequential)

 

 

 

 

pacing (<2 mA)

 

 

 

Output three to four times of threshold

Transcutaneous needle temporary pacemaker should not be used in current technology as it has serious complications

Insertion Pacemaker Temporary 95

763

764

R. Chawla and V. Roy

 

 

5. Advance the electrode under ultrasound or fluoroscopic guidance until it lies vertically in the right atrium with its tip pointing toward the free wall on the right side.

6. Rotate the wire between the index finger and the thumb so that it points toward the patient’s left side; advance the wire steadily through the tricuspid valve and along the floor of the right ventricle to the apex.

7. If blind technique is used, the V1 lead is connected to the distal port (cathode). Endocardial contact is indicated by prominent ST-segment elevation. Placement is facilitated by balloon inflation and floatation in the superior vena cava. Position is confirmed by successful capturing. For placement in the right ventricular apex, the balloon is deflated and the catheter is advanced a few centimeters. This technique is practiced in the emergency department where fluoroscopy and ultrasonography is unavailable instantly.

8. The anteroposterior and lateral X-ray after placement is always indicated. 9. If AV sequential pacing is desired, the atrial J-shaped pacing catheter should

be advanced into the right atrium and rotated anteromedially to achieve a stable position in the right atrial appendage; positioning the atrial catheter usually requires fluoroscopy.

C.Setting the Pacemaker

1. Keep the pacemaker box in off position and attach the leads to the ventricular output position.

2. Turn the pacemaker into asynchronous mode and set the ventricular rate 10–20 beats/min higher than the patient’s intrinsic rate.

3. Set the threshold current for ventricular pacing at 5–0 mA and switch the pacemaker on. See for ventricular pacing as evidenced by a wide QRS complex, with ST-segment depression and T-wave inversion, following each pacemaker depolarization (spike). (Right ventricular apex pacing presents as a pattern of left bundle-branch block on the surface ECG.)

4. Output current is slowly reduced and the threshold current (the lowest current at which consistent ventricular capture occurs) is determined. Recommended pacing threshold of less than 0.5–1.0 mA should be achieved.

5. If the threshold is high, then consider relative endocardial refractoriness due to fibrosis (rare) or a malposition of the electrode (more common). In any case, the tip of the pacing electrode should be repositioned in the region of the ventricular apex until satisfactory ventricular capture at a current of less than 1.0 mA is consistently maintained.

The ventricular output is set to exceed the threshold current at least threefold. The pacemaker is now in VOO mode.

After insertion of the lead and before stitching the lead, withdraw the sheath as it reduces infection rate.

For blind pacing without the balloon-tipped lead, use left subclavian access.

95 Temporary Pacemaker Insertion

765

 

 

Step 4: Know the modes

 

 

 

 

Programmability

Multisite

 

 

 

 

(R, programmable;

pacing

 

Paced

Sensed

 

O, nonprogram-

(A, multisite

 

(A, atrium;

(A, atrium;

 

mable; M,

pacing; O,

 

V, ventricle;

V, ventricle;

Response (I, inhibit;

multiprogram-

nonmultisite

Modes

D, dual)

D, dual)

T, trigger)

mable)

pacing)

VVI

Ventricle

Ventricle

A sensed event in the

None

None

 

 

 

ventricle inhibits the

 

 

 

 

 

pacemaker from

 

 

 

 

 

pacing or producing

 

 

 

 

 

any output

 

 

AAI

Atrium

Atrium

The sensing of an

None

None

 

 

 

event (e.g., sensing

 

 

 

 

 

atrial activity within

 

 

 

 

 

1 s) inhibits the

 

 

 

 

 

pacemaker from

 

 

 

 

 

pacing

 

 

DDD

Both

Both

Response can be

None

None

 

 

 

both triggering

 

 

 

 

 

and inhibitory

 

 

Set the mode according to the need and device

Step 5: Know the complication and management

Complications

1.Complications as with any route—pericardial friction rub, arrhythmia, right ventricular perforation, cardiac tamponade, infection, arterial injury, diaphragmatic stimulation, phlebitis, and pneumothorax

2.Complications of internal jugular venous and subclavian access—pneumotho- rax, carotid arterial injury, venous thrombosis, and pulmonary embolism

3.Complication of antecubital venous access—dislodgement of the pacing electrode from a stable ventricular or atrial position (movement of the arm) and infection (more with this approach than others)

4.Complication of femoral access—deep venous thrombosis and infection

Management

1. Optimum knowledge about the anatomy and the procedure

2. Ability to evaluate the correct placement and the desired rhythm 3. Strict intraand postprocedural asepsis.

Step 6: Troubleshooting

1.Satisfactory pacing not achieved: Withdraw the wire into the right atrium and repeat the attempt to cross the tricuspid valve.

2.Difficulty in positioning the wire at the apex of the right ventricle: Pass the tip of the wire into the right ventricular outflow tract and withdraw gently while rotating

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