Glucose monitoring in the ICU or critical care setting is one of many crucial measurements that requires constant attention by hospital staff. This type of monitoring involves a needle to draw blood; and this could lead to hospital-acquired infection. One thing a doctor doesn't want to do is "add lines” to a patient; he or she would rather remove them.

One company is working to take the needle out of glucose monitoring.

Echo Therapeutics (Franklin, Massachusetts) has reported positive results from its clinical study of its Symphony tCGM system, a non-invasive, transdermal continuous glucose monitoring (tCGM) system, the trial conducted at the Tufts Medical Center (Boston).

Echo is developing the Symphony tCGM system to provide patients with diabetes and healthcare professionals with a needle-free, wireless, continuous monitoring system to better manage diabetes and control blood glucose levels in the home use and hospital critical care settings. Echo said that data from the pilot study showed that Symphony safely and reliably monitored blood glucose levels in the operating room and surgical intensive care unit at Tufts.

"We believe that glucose levels are going to be the fifth vital sign,” Echo president/CEO Patrick Mooney, MD, told reporters in a conference call. "The main difference in our product [compared to competitors] is that you do not need a needle with our system to inject a sensor. Our sensor sits at the top of the skin; we prep the skin either through gentle dermabrasion or through an ultrasound based method, so there is no needle to insert a sensor under the skin, and our monitors only need to recalibrate twice in a 24-hour time period.”

"We are proud to be the first company to report positive clinical data on a non-invasive, transdermal continuous glucose monitoring system in the hospital critical care setting,” said Mooney. "We are excited about the potential for our program in this area and look forward to continued progress with tCGM in both the home and hospital settings, with further studies planned throughout 2008.”

Patients in the hospital setting need to check their glucose frequently. Finger stick capillary blood glucose monitoring is the standard of care for managing one's glucose levels. For critically ill patients in the hospital setting — with or without diabetes — glucose levels are checked more frequently.

In fact, in some hospitals, glucose levels are checked as frequently as every hour. In the hospital, frequent glucose testing places unnecessary strain on the nursing staff, explained Mooney.

The pilot study was designed to evaluate the performance of the Symphony tCGM system, including the use of its ultrasound-based skin permeation system and biosensor technology incorporating proprietary hydrogel chemistry. The study enrolled 25 adult patients scheduled for elective cardiac surgery. The study included both intra-operative and post-operative continuous monitoring of blood glucose (BG) levels.

Two biosensors were applied to each subject, one prior to surgery and one after. Both Symphony sensors remained on the patient for 24 hours. BG levels were monitored according to the protocol developed by Tufts. The participating subjects and the Tufts medical staff were blinded to data collected by the Symphony monitor.

In the trial, the continuous data were compared to reference measurements from blood analyzers, glucometers and lab results based on the Tufts glucose monitoring protocols. Those reference measurements were paired with the Symphony results through a data analysis algorithm.

Using around 1,200 hours of continuous data from Symphony and 482 reference BG measurements from the 25 subjects, Clarke Error Grid analysis of the study data showed that Echo's Symphony had more than 97% of the data in the combined "A” and "B” areas with about 70% in the "A” region, 27% in the "B” region, and less than 3% in the "D” region.

"Critically ill patients need tighter glycemic control to minimize morbidity and mortality,” said Stanley Nasraway, MD, director of surgical intensive care units at Tufts and the principal investigator of the study. "These data serve as a strong signal that Symphony could advance the standard of care regarding tight glycemic control in the hospital critical care setting, much like continuous electrocardiographic monitoring and pulse oximetry changed standards of care in that setting.

"This approach could provide doctors and nurses with breakthrough continuous blood glucometry technology and significantly improve our ability to monitor glucose levels of seriously ill patients in the intense intra-operative and post-operative settings.”

Mooney said that the devices are the same configuration for home and ICU monitoring and he didn't anticipate that to change.