Pacemaker Learning Package
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- Điều hướng trang này:
- Sensing Threshold
- Medtronic Pacing Glossary. 2005 Liverpool Hospital
- TRANSCUTANEOUS PACING
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P a g e “Unless you try to do something beyond what you have already mastered, you will never grow." Ronald E. Osborn Sensitivity: Is the pacemaker’s ability to sense a patient’s intrinsic rhythm or when natural depolarization is occurring The sensitivity number represents the minimum size, in millivolts, of an electrical signal that will be detected by the pacemaker The higher the sensitivity (number) the less likely the pacemaker will see the patients rhythm Sensing Threshold: The minimum atrial or ventricular intra cardiac signal amplitude required to inhibit or trigger a demand pacemaker, expressed in millivolts. Stimulation or output Threshold: The minimum electrical stimulus needed to consistently elicit a cardiac depolarization. It can be expressed in terms of amplitude (volts, milliamps) and pulse width (milliseconds), or energy (microjoules). Triggered: In pacemaker terms, a Triggered pacing mode is the opposite of inhibited. Upon detecting a spontaneous depolarization or other signal, a triggered mode will deliver an electrical stimulus to the heart. Medtronic Pacing Glossary. 2005 Liverpool Hospital Intensive Care: Learning Packages Intensive Care Unit Pacemaker Learning Package LH_ICU2016_Learning_Package_Pacemaker_Learning_Package 13 | P a g e TYPES OF PACING TRANSCUTANEOUS PACING Is only used in emergency situations due to the discomfort felt by the patient. The electrodes are incorporated into the pads and cover a large surface area over the skin. The pads are connected to an external pulse generator which delivers energy through the pads to the chest wall muscles. Figure 4: Pacing pad placement for trancutaneous pacing. Lippincott’s Nursing centre.com 2011 By continuously monitoring cardiac rate and rhythm and delivering pacing impulses through the skin and chest wall muscles as needed, trancutaneous pacing causes electrical depolarization and subsequent cardiac contraction to maintain cardiac output until the patient receives a transvenous pacemaker The pacing stimulus travels through chest wall, pectoralis and intercostals muscle, ribs pericardial fluid and fat before finally reaching the heart. Therefore a much higher energy level is needed to deliver the correct energy to the heart. One side effect of this is chest muscle contraction from the electrical stimulus. Therefore giving the patient some sedation for comfort is high priority Pacing or defibrillation pads must be in good contact with chest wall Once capture has been verified on monitor by a spike before every QRS, patient’s haemodynamics must also be assessed ensuring electrical and mechanical capture. |