Intraoperative Warming During Major Surgical Procedures Using the Esophageal Temperature Management System

Maintaining patient's body temperature is of major importance in patients undergoing surgical
procedures and existing methods to warm patients to maintain perioperative normothermia have
limitations. This results in as many as half of patients undergoing surgery developing
inadvertent hypothermia during and/or after their procedure. The EnsoETM is an Esophageal
Temperature Management (ETM) device consisting of a multi-chambered silicone tube connected
to a heat exchanger and placed in the esophagus, providing highly efficient heat transfer to
a patient. The EnsoETM potentially improves the ability to control patient temperature by
eliminating the disadvantages of existing methods while maintaining the functionality of the
orogastric tube that it replaces.

The primary objective of this study is to measure the number of degree-hours spent below 37°C
intraoperatively and until recovery in the PACU. This measure will be compared between
patients having standard management of body temperature to patients having the EnsoETM placed
as an additional warming device.

Inclusion Criteria:

- Provision of signed and dated informed consent form

- Male or female, ages 18 years and older

- Scheduled for major surgical procedures requiring general anesthesia and with no known
contraindication to having an orogastric tube placed for the duration of the surgery

- The time in the OR is expected to last at least 180 minutes

Exclusion Criteria:

- Esophageal strictures (risk of perforation)

- Patients with known esophageal deformity or evidence of esophageal trauma (for example
history of esophagectomy, previous swallowing disorders, achalasia, etc.)

- Known ingestion of acidic or caustic poisons within the prior 24 hours.

- Patients with <40 kg of body mass

- Coagulopathy

- Severe facial trauma

- Surgical procedures lasting less than 3 hours