This study is part of a post-market clinical follow-up (PMCF). The purpose of this study is to verify in a routine clinical environment with a number of caregivers and subjects that the enFlow performs as intended when used as an element of maintaining acceptable core temperatures.

Eligible subjects from the study will be recruited from patients with scheduled surgeries. After being informed about the study and potential risks, patients given informed consent will undergo scheduled surgery with the use of enFlow IV Fluid and Blood Warming System. The following temperature measurements will be collected during surgery:

• Baseline temperature measurement (0-15 minutes prior to induction)
• Induction temperature measurements (15 minutes, 30 minutes, 60 minutes, 90 minute post-induction)
• Continued temperature measurements (every 30 minutes, plus end of surgery)
• OR ambient temperature at induction and end of surgery.

Temperature will be measured and collected post-surgery upon arrival to the PACU and 30 minutes post-arrival.

Inclusion Criteria:

• 18 years of age or older
• Patients requiring surgery expected to last at least 1 hour.
• Expectation of the perioperative need for at least one liter of infused fluids warmed during infusion
• Informed Consent

Exclusion Criteria:

• Recent history of fever (>38 C, within 24 hours of surgery)
• Active infection
• Pregnant women
• Terminal illness (<30 days)
• Intended use of cardiopulmonary bypass
• Clinical intention for perioperative cooling and hypothermia
• unavailability of esophageal measurement during surgery
• Attending physician does not believe participation of the patient is in their best interest.

Subjects from the study will be recruited from patients with scheduled surgeries. Most are expected to be inpatient due to the exclusion of short surgeries. For this study, only adults will be enrolled. Participation will also be limited to patients fluent in the language(s) of the information and consent form.