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Updated: Dec 29, 2025
09:43
Functional and Morphological Assessment of Diaphragm Innervation by Phrenic Motor Neurons
Published on: May 25, 2015
18.1K
Sudden onset pacemaker-induced diaphragmatic twitching during general anesthesia
Kanae Tanabe1, Masakazu Kotoda2, Daiki Nakashige1
1Department of Anesthesiology, University of Yamanashi, 1110 Shimokato, Chuo, Yamanashi, 409-3898, Japan.
JA Clinical Reports
|February 7, 2020
Summary
Pacemaker stimulation can rarely cause involuntary muscle contractions. A patient experienced sudden diaphragmatic contractions after pacemaker reprogramming, likely due to phrenic nerve stimulation near the lead.
Area of Science:
- Cardiology
- Medical Devices
- Anesthesiology
Background:
- Involuntary muscle contraction is a rare complication of pacemakers.
- Extracardiac stimulation can induce these contractions.
- Diaphragmatic contractions are an unusual presentation.
Purpose of the Study:
- To report a case of sudden diaphragmatic contractions during general anesthesia.
- To investigate the cause of these contractions in a patient with a DDD mode pacemaker.
Main Methods:
- A 74-year-old woman with a permanent pacemaker underwent mastectomy.
- Pacemaker mode was switched from DDD to VOO intraoperatively, then back to DDD.
- Diaphragmatic contractions occurred postoperatively and ceased after adjusting pacing mode.
Main Results:
- Sudden onset diaphragmatic contractions mimicked bucking movements.
- Twitching ceased upon switching pacing to A-sense V-pace.
- No structural abnormalities were identified.
Conclusions:
- Diaphragmatic contractions may result from phrenic nerve stimulation by the pacemaker lead.
- Preoperative evaluation of muscle twitching risk is crucial, especially with atypical lead placement.
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