Wireless Assessment of Respiratory and Circulatory Distress - Continuous Glucose Monitoring

Continuous Glucose Measurements to Detect Hypoglycemia in Patients Undergoing Major Surgery

The applicant and research team partners have over the last years developed the WARD project (Wireless Assessment of Respiratory and circulatory Distress), using wireless continuous monitoring of vital signs in high-risk patients undergoing major abdominal surgery. An important perioperative indicator not currently included in the WARD project is continuous glucose monitoring (CGM), which may not only predict and identify hypo- and hyperglycemia, but also utilize the information from variations in blood glucose in combination with other changes in vital signs to predict surgical complications in all patients.

The current study involves the inclusion of 80 patients, scheduled for major abdominal, orthopedic or vascular surgery, to be monitored with CGM in addition to the currently measured vital signs. The project is a prospective, observational, clinical study, describing and analyzing variations in perioperative blood glucose levels and vital signs, and the relation to adverse clinical outcomes.

Patients scheduled for elective surgery will preferentially be recruited at the preoperative assessment at a maximum of 30 days before surgery. CGM and monitoring of the remaining vital sign modalities will commence on the day of surgery. Patients admitted for acute surgery will be recruited preoperatively and CGM as well monitoring of the remaining vital sign modalities will commence as soon as possible. The patients will be monitored with CGM for up to 10 days and with the remaining modalities for up to 5 days or for all modalities until discharge or withdrawal of consent.

Inclusion Criteria:

• Adult patients (≥18 years) admitted to Rigshospitalet or Bispebjerg Hospital for major abdominal surgery (e.g. colonic resections, gastrectomy, hepatic resection etc.) or major orthopedic surgery (e.g. hip-fracture, hip and knee-arthroplasty) or major arterial vascular surgery (e.g. aortic aneurysm, iliac or femoral bypass etc.)
• Estimated duration of surgery ≥1 hour and at least one expected overnight stay postoperatively

AND

● Type 1 diabetes (Clinically defined: insulin initiated at diabetes onset and treatment with multiple doses of insulin or continuous subcutaneous insulin infusion) (n=20)

OR

● Type 2 diabetes treated with insulin (Clinically defined: treatment with diet or oral antidiabetic drugs for at least 6 months before insulin was started) (n =20)

OR

● Type 2 diabetes treated with oral antihyperglycemic drugs and/or GLP-1 analogs (n=20)

OR

● No diabetes mellitus (excluded by an admission HbA1c <48 mmol/mol) (n=20)

Exclusion Criteria:

• Patient expected not to cooperate with study procedures.
• Patient allergic to plaster or silicone.
• Patients with impaired cognitive function (assessed by a Mini Mental State Examination [MMSE] score <24)
• Patients admitted for palliative care only.
• Previous or currently scheduled for pancreatectomy (complete or partial)
• Patients with pacemaker or implantable cardioverter defibrillator (ICD) device