Given the increased strain on nursing staff during the COVID-19 pandemic, Libre sensors were repeatedly being mistakenly removed and discarded by nursing staff prior to data collection.

Currently, the standard of care for monitoring sugar levels in patients with diabetes in the intensive care unit is to use finger stick blood sugar monitoring. Finger stick blood sugar monitoring can be uncomfortable and time consuming. An alternate way to monitor sugar levels to use a sugar sensor, as part of the Abbott Freestyle Libre Flash glucose monitoring system, which has been approved for use outside of the hospital. The goal of the current research is to see whether using the sugar sensor gives accurate sugar readings in patients that are ill enough to be in the intensive care unit. If research confirms that the sensor is accurate, the investigators could potentially need to do fewer of those uncomfortable and time consuming blood sugar finger sticks.

At this time, the Freestyle Libre Flash Glucose Monitoring system is not available for purchase without a specific prescription for each individual patient and also is not available for purchase for research use from the manufacturer, Abbott Laboratories. However, the Freestyle Libre Pro sensor is available and uses the same measurement technology to measure interstitial glucose as the Libre Flash Glucose Monitoring system sensor (but does not require sensor scanning to retain glucose data). As such, the Libre Pro sensor will be utilized for the current study.

When a participant is enrolled in this study, they will have a Abbott Freestyle Libre Pro sensor applied to the back of their arm. They will continue to have finger stick glucoses checked as determined by their primary medical ICU team just as if they would if not enrolled in the study.

After the participant leaves the hospital, the data from their finger stick glucoses and from the Libre will be compared by a statistical analysis to see how similar or different the glucose readings from the finger stick glucoses are as compared to the Libre sensor data.

This will be a single center, prospective, single arm study including 40 adult patients with Type I or II diabetes, 18 years of age or older, admitted to the Medical Intensive Care Unit (MICU) at the Hennepin County Medical Center during a 4 month time-frame with an expected MICU admission duration of at least 48 hours.

Once patients are deemed eligible based on inclusion and exclusion criteria, patients or their legal authorized representative (LAR) decision makers (if patient is unable to consent) will be approached by the PI or co-investigators. The consent form will be read out loud clearly to the patient or LAR. They will be given an opportunity to read it themselves if they so choose and also ask clarification questions as needed. Patients or LAR will be asked to recall details of the study to confirm understanding and assess capacity to consent. If patient or LAR accepts to be part of the study, the investigators will ask that a consent form be signed. The patient will be provided a copy of the consent and the original copy will be provided to the Health Information Management (HIM) department for secure storage.

Once the consenting process is completed, investigators will place the Libre pro sensor on the back of one of the arms of the patient using the applicator provided with the Libre monitor (see appendix). Investigators will confirm that the device is operational.

The sensor will remain in place for the duration of the patient's hospital stay and be removed prior to discharge. Sensors last a total of 14 days. If a patient remains in the hospital for greater than 14 days, the sensor will be collected on day 14 of hospitalization and will not be replaced with a new sensor. The sensor does need to be removed for CT scans, MRI scans or diathermy. If the sensor is removed for these reasons, a new sensor will be placed after completion of the imaging or procedure. Patients will be followed during their hospitalization in the MICU and after they have been transferred out of the MICU. If a patient discharges during normal business hours of 8AM to 5PM, study investigators will remove and store the monitor and sensor for future data analysis in a locked cabinet. If a patient discharges at any other time (nights and weekends), nurses will remove the sensors. Sensors are easy to remove and nurses will not require special training to remove the sensors. Nurses will store the sensor in a labeled plastic bag and then place the bag in the nursing station medication room. This room requires badge access. The sensor will be picked up by study investigators the following business day.

Nurses or medical assistants will conduct standard of care (SOC) capillary fingerstick glucose monitoring per hospital protocol for patients with diabetes. Nurse decision making will be based on capillary fingerstick glucose monitoring (SOC) alone. FGM glucose level will not be obtained prior to sensor removal. As such, FGM glucose levels will not be available for decision making. Nurses, medical assistants, and clinician researchers will be blinded to glucose data collected via FGM until the study concludes and data analysis begins.

The patient satisfaction and nurse acceptance surveys will be administered on the day of discharge or the day prior to discharge if the patient is expected to be discharged the next morning. If a patient is discharged before completing the survey, investigators may contact the patient by phone to complete the survey. There will otherwise be no follow up after discharge.

Inclusion Criteria:

• Males or females age 18 and older. There is no upper age limit.
• English speakers.
• History of Type 1 or Type 2 diabetes (noted in electronic medical record or confirmed by patient or LAR).
• Admission to the medical intensive care unit with expected stay of at least 48 hours

Exclusion Criteria:

• New diagnosis or no known history of type 1 or type 2 diabetes.
• Patients with documentation stating desire not to participate in research.
• Prisoners.
• Documented allergy to adhesives or tape.

No masking of whether participant is enrolled will take place. Data from sensor will be masked from the participant, care provider and investigator during sensor use.