Hydrotherapy Wrapping, St. Elizabeths, courtesy National Archives
The plunge bath, douche bath, continuous bath, needle bath, and so on, fell under hydrotherapy treatment. In theory, the treatment should have been effective and fairly humane. Warm, soothing baths would help patients sleep, while a plunge bath, using water at temperatures between 45-70 degrees, might shock a violent patient into settling down. Though uncomfortable, such a treatment was preferable to being wrestled to the ground or restrained.
Even at the best of times, hydrotherapy tended to be uncomfortable. Many doctors thought cold water treatment was superior to warm, and believed treatments should be administered in the morning just as the patient arose. Many medical people believed that warm baths opened up the pores so that a person could catch cold more easily.
Plunge baths and other cold water hydrotherapy were believed to be invigorating for patients, though other doctors thought it absurd to think that any person–sick or well–would enjoy emerging from a warm bed in order to plunge into a cold bath. Unfortunately, patients had no say in the matter and had to live with whichever theory their own doctor adhered to.