Recent studies have reported parasympathetic ganglia supplying the regions around the sinoatrial node (SAN) are situated in the pulmonary vein fat pad (PVFP). Otherwise, in coronary artery bypass grafting (CABG) without cardiopulmonary bypass, cardiac surgeons expect effective support technique on heart rate. The purpose of this study was to determine the feasibility of inducing sinus bradycardia by stimulating these parasympathetic nerve fibers to the SAN in humans. Nine patients were anesthetized and median sternotomy was performed. Bipolar electrodes were sewn onto PVFP to stimulate parasympathetic nerve fibers to the SAN. PVFP was electrically stimulated with a 4-9 V pulse of 0.1msec and a frequency of 5, 10, 20, or 50Hz. Sinus bradycardia was induced by selective stimulation of the parasympathetic nerve fibers to the sinoatrial node. The response was frequency-dependent up to 20Hz. Heart rate was significantly reduced from 90.1±12.4 to 71.4±15.7 (beats/min) at 20Hz. This technique could be applied for reducing heart beats in CABG without cardiopulmonary bypass. However, there are problems in maintaining of the effect.

Background: Excessive bleeding is a major intraoperative risk associated with orthognathic surgery. This study aimed to investigate the factors involved in massive bleeding during orthognathic surgeries so that safe surgeries can be performed. Patients (n=213) diagnosed with jaw deformities and treated with bimaxillary orthognathic surgery (Le Fort I osteotomy and bilateral sagittal split ramus osteotomy) in the Department of Oral and Maxillofacial Surgery at the Suidobashi Hospital, Tokyo Dental College between January 2014 and December 2016 were included. Using the patients’ medical and operative records, the number of cases according to sex, age at the time of surgery, body mass index (BMI), circulating blood volume, diagnosis of maxillary deformity, direction of maxillary movement, operative duration, incidence of bad split, injury of nasal mucosa, and blood type were analyzed. Results: The results revealed that BMI, circulating blood volume, nasal mucosal injury, and operative time were associated with the risk of intraoperative massive bleeding in orthognathic surgeries. Chi-square tests and binomial logistic regression analyses showed significant differences in BMI, circulating blood volume, direction of maxillary movement, operative duration, and injury to the nasal mucosa. Operative duration emerged as the most important risk factor. Furthermore, a >4-mm upward migration of the posterior nasal spine predicted the risk of massive bleeding in orthognathic surgery. Conclusions The upward movement of the maxilla should be recognized during the preoperative planning stage as a risk factor for intraoperative bleeding, and avoiding damage to the nasal mucosa should be considered a requirement for surgeons to prevent massive bleeding during surgery.

Bilateral shoulder joint disorders caused by rheumatoid arthritis significantly impair daily functioning owing to a lack of contralateral compensation. In Japan, reverse shoulder joint prostheses were approved in 2014. This was expected to improve the surgical outcomes of rheumatoid shoulder arthroplasty. We report two patients with rheumatoid arthritis who underwent bilateral reverse shoulder arthroplasty. This study aims to evaluate their postoperative clinical outcomes and activities of daily living. The patients were women in their 70s with stage III class 2 rheumatoid arthritis. Their treatment and postoperative activities of daily living were retrospectively reviewed. The first patient underwent the inlay type and experienced a residual limitation of external rotation postoperatively; therefore, she was restricted to dress with front-open clothes. However, she was able to undress after the lining of the garment was changed to a slippery material. The second patient underwent the onlay type and showed almost no limitations in postoperative activities of daily living. She was able to undress with an external rotation of 40–50°. Bilateral reverse shoulder arthroplasty improved range of motion, the Japanese Orthopaedic Association shoulder score, and functional outcomes. Only a few difficulties were encountered in the activities of daily living.