Postoperative observation of patients is based on the Early Warning Score (EWS). By using continuous wireless monitoring of vital parameters it may be possible to predict the risk of complications after abdominal cancer surgery. The object of this pilot study is to test the equipment and methods for the next phases. Patients will be monitored for 4 days postoperatively and data is analyzed retrospectively. Vital parameters are monitored with ECG, blood pressure monitor and pulseoximetry.

In the analysis the investigators will compare the results from the continuous monitoring to the measurements made by the nurses and registered in the EWS. The primary outcomes for the pilot study are the frequency of measurements resulting in a single parameter score of 3 according to the EWS algorithm.

Inclusion Criteria:

• Diagnosis of cancer of either esophagus, stomach, pancreas, liver, colon or rectum.
• Elective surgery with curative intention at Bispebjerg Hospital or Rigshospitalet in Copenhagen, Denmark.
• Estimated duration of surgery > 2 hours
• > 65 years
• Preoperative ECG showing sinus rhythm
• No treatment limitations
• Fit to receive optimized care according to the regimens on the given wards

Patients undergoing major abdominal cancer surgery with a curative intention at either Bispebjerg Hospital or Rigshospitalet.