Dental Management of Patients with Autonomic Dysfunction: Significance of Intraoperative Monitoring by Heart Rate Variability Analysis

Autonomic dysfunction (AD) is generally regarded as an uncommon disease in dentistry.  AD easily leads to disturbance in circulatory dynamics; however, most dental practices haven’t realized the importance of managing AD.  Autonomic activity in AD during dental therapy has not previously been measured or elucidated.  Heart rate variability (HRV) analysis is useful to assess autonomic activity and to diagnose autonomic neuropathy, for HRV is biomarkers for the functions of the autonomic nervous system (ANS) [1,2].  HRV analysis was performed with an HRV analyzer (SA-3000P, Tokyo Iken Co., Ltd., Tokyo, Japan).  The HRV analyzer looks like a pulse oximeter and analyzes pulse-to-pulse variations in pulse rate by a built-in HRV analyzing system; it enables easy measurement of autonomic activity without inducing any stress in patients.  We experienced two rare cases of AD manifested during dental therapy and intraoperatively monitored by HRV analysis; we assessed the clinical significance of HRV analysis for AD in a dental practice. 

The first case is AD-associated orthostatic dysregulation (OD) manifested during postural change on the dental chair.  The patient was a 17-year-old Japanese female.  She attended the Department of Oral Surgery and Dental Anesthesiology, Tokushima University Hospital.  She was diagnosed with impacted wisdom teeth and had no previous history of a distinct systemic disease.  A surgical procedure to extract the teeth was safely performed under both local anesthesia and sedation with nitrous oxide and midazolam.  After the surgery, her postural change to sitting induced orthostatic hypotension (systolic/diastolic blood pressure (S/DBP): 65/25 mmHg).  Compensatory tachycardia and syncope weren’t found.  HRV variables showed parasympathetic dominance due to the upright position.  Subsequently her posture was returned to supine, and atropine sulfate administration for the immediate treatment of OD returned her blood pressure to normal levels.  HRV variables showed relative sympathetic dominance due to an atropine-derived parasympathetic blockade. 

The second case is AD-associated adrenergic urticaria (AU) induced by stress during dental therapy.  The patient was a 53-year-old Japanese female.  She attended the Department of Fixed Prosthodontics and Dental Anesthesiology, Tokushima University Hospital.  She was given the diagnosis of periodontitis, and had no previous history of systemic disease.  In the course of the dental therapy, her blood pressure and heart rate were abnormally elevated (S/DBP: 200/111 mmHg, heart rate: 131 bpm); urticarias also developed.  Furthermore, almost all parameters derived from HRV analysis changed with the intensity of loaded stress by the therapy.  The appearance of these manifestations including the urticarias closely correlated with the values of HRV parameters, notably low frequency (LF) noun, high frequency (HF) noun, and LF/HF ratio, changing with the intensity of loaded stress by the therapy.  At the end of the therapy, all paroxysmal manifestations including urticarias spontaneously subsided without any medicine. 

In conclusion, HRV analysis revealed OD- or AU-inducing AD.  Our experience emphasizes the importance of HRV analysis with respect to secure and safe dental management of AD patients. 

These procedures were explained to the patients.  Then, their informed consents were obtained. 

The authors declare that there is no conflict of interests regarding this study. 

This work was supported by JSPS KAKENHI, Grant Number 25463247. 

References

 [1] Akselrod S, Gordon D, Ubel FA, Shannon DC, Berger AC, Cohen RJ. Power spectrum analysis of heart rate fluctuation: a quantitative probe of beat-to-beat cardiovascular control. Science 1981; 213: 220-2. 

[2] Momota Y, Takano H, Kani K, Matsumoto F, Motegi K, Aota K, Yamamura Y, Omori M, Azuma M. Frequency analysis of heart rate variability: a useful assessment tool of linearly polarized near-infrared irradiation to stellate ganglion area for burning mouth syndrome. Pain Med 2013; 14: 351-7.