Situation

A patient with a pacemaker comes for thoracomy. What do you do?

Opinion

Opinion

The pacemaker will need checking and changing to DOO-dual chamber or VOO-single chamber, so as the diathermy does not interfere with it. Post operatively the pacemaker should be switched back to its original mode and the sensitivities checked.

Implantable pacemakers

Indications for a pacemaker

sinus bradycardia,

 sick sinus,

slow atrial fibrillation,

Mobitz II,

and complete heart block.

Pacemaker modes

  A five letter code is used to identify different modes of pacemaker function.

The first three letters refer to anti bradycardia functions, and external pacing modes.

POSITION I: the first letter refers to the chamber(s) paced: 

O(None),

A(atrial),

V(venticular),

or D(both atrial and ventricular).

POSITION II: refers to the chamber(s) sensed:

O(None),

A(atrial),

V(venticular),

or D(both atrial and ventricular).

POSITION III: refers to the response to sensing(if any). This may be

I (for inhibition) - a pacemakers discharge is inhibited (switched off) by the sensed signal.

T (for triggering) - a pacemaker's discharge is triggered by a sensed signal.

POSITION IV: refers to the ability to change externally certain parameters of the permanent internal pacemaker. Possibilities are

P simple programmability, an ability to change simple parameters, usually the rate and current output only.

M multi-programmability, an ability to change more parameters.

T or communicating, a telemetry function of the internal pacemaker.

R or rate adaptive, the ability to vary the pacing rate through one or more physiological variables. Sensors include vibration, Q-T intervals, respiration, blood pH and right ventricular oxygen saturation.

POSITION V: refers to the tachyarrhymic functions

P for pacing tachycardias

S for shocking, ability to DC shock ventricular tachycardia(VT) or fibrillation(VF).