Pneumoperitoneum affects hemodynamics and generally increases the mean arterial pressure, systemic vascular resistance, pulmonary vascular resistance, heart rate, and central venous pressure, but reduces venous return and cardiac output [
5]. The incidence of arrhythmia because of pneumoperitoneum is said to range from 14 to 27% [
3], the majority of which is sinus tachycardia and extrasystole. However, on rare occasions, severe bradycardia (sinus bradycardia and atrioventricular conduction disturbance) is presented, which is considered to be attributed to a vagal reflex. The reported causes underlying the onset of an excessive vagal nerve response include peritoneal stretching, attributable to pneumoperitoneum, and intraoperative manipulations involving organs within the abdominal cavity [
5,
6]. In laparoscopic radical prostatectomy, Trendelenburg positioning under general anesthesia might cause severe bradycardia [
7]. In our present case, immediately after the start of pneumoperitoneum, bradycardia and CAVB were observed, the cause of which was considered to be a vagus nerve response to peritoneal stretching. Note that highly frequent causes of CAVB are said to include ischemic heart disease and cardiomyopathy. However, the CAG performed after the surgery revealed no explicit results. In terms of peritoneal stretching because of pneumoperitoneum, when the rate of CO
2 insufflation starts at a slow rate, it is unlikely that a vagus reflex would occur [
8]. Moreover, in the present case, it is possible that if the CO
2 insufflation rate was increased over a longer period, then the excessive vagus reflex could have been avoided. Typically, in the event of sinus bradycardia, atropine administration is considered. Nevertheless, in our present case, CAVB was observed; hence, we decided to treat the patient by pacing. In RARP, the patient is docked to a patient cart during surgery. When surgery is interrupted to administer respiratory or circulatory emergency procedures, the cart must be detached from the patient, which makes an immediate response more difficult, compared with regular laparoscopic surgery routine. Therefore, we completed the surgery after inserting a TPM, which enabled more reliable pacing than transcutaneous pacing and a favorable outcome.
To the extent of our literature search, this is the first report of surgery performed after inserting a TPM for bradycardia development during RARP. In surgery using pneumoperitoneum, severe bradycardia can, on rare occasions, cause cardiac arrest and therefore requires proper treatment. In robot-assisted surgery, it is important to have countermeasures for complications because it is difficult to interrupt surgery and immediately perform emergency procedures.