POTS/CFS and the dentist's chair...
I've also read that people with the disorders need to be careful if the barber washes their hair. The position of the head bent into the sink is perilous.
http://jada.ada.org/cgi/content/abstract/137/4/488
CLINICAL PRACTICE
JADA Continuing Education
Postural orthostatic tachycardia syndrome
Dental treatment considerations
John K. Brooks, DDS and Laurie A.P. Francis, RDH
Background. Postural orthostatic tachycardia syndrome (POTS) is a chronic, relatively common autonomic disorder typically affecting younger females. It is distinguished by a dramatic increase in heart rate on the assumption of an upright posture from the supine position.
Methods. The authors provide an overview of the demographics, clinical assessment, diagnostic features, differential diagnoses, pathogeneses and medical treatment of patients with POTS, with an emphasis on the clinical treatment of the dental patient affected by the syndrome.
Conclusion. Patients frequently exhibit symptoms of lightheadedness, fatigue, palpitations and syncope. Patients with POTS may have Ehlers-Danlos syndrome, mitral valve prolapse, chronic fatigue syndrome or, rarely, the Brugada syndrome. Despite widespread dissemination of information regarding POTS in the medical literature, scant information on it has appeared in dental publications.
Practice Implications. Dentists need to be familiar with the clinical features of POTS and be prepared to treat patients at risk of developing syncope.
Key Words: Postural orthostatic tachycardia syndrome; autonomic disorder; dental treatment