Masimo's RRa provides similar respiration rate accuracy as capnometry for extubated patients

Masimo (NASDAQ: MASI) announced today a new study published in the May 2012 edition of the British Journal of Anaesthesia demonstrates that Masimo's acoustic respiration rate (RRa™) from rainbow® Acoustic Monitoring provides similar respiration rate accuracy as capnometry for extubated patients.

Respiratory depression is common during early postoperative periods, especially after extubation (removal of the breathing tube) and when narcotic analgesics are required for pain management. Delayed detection of respiratory depression increases the risk of major neurological damage and death.  Continuous monitoring of oxygenation and ventilation is recommended for all patients after general anesthesia. Capnometry is commonly used for intubated patients but in extubated patients, capnometry requires a nasal cannula or face mask that may be poorly tolerated or can be dislodged, leading to errors in data acquisition and false alarms.

In the study, conducted at the University Hospital of Poitiers, France, researchers evaluated 52 post-surgical patients in the post-anesthesia care unit and compared the accuracy of RRa (Masimo Rad-87® with rainbow® Acoustic Sensors) and capnometry using a face mask (Oridion Capnostream 20™ with Oridion Capnomask™).  Patients were monitored for 16 to 60 minutes over a range of 6 to 24 breaths per minute, for a total of 99,002 data pairs.  Differences in respiration rate of >4 bpm for 20 seconds or more between the two devices led to 28 clinical assessments of respiration rate, with 46% of errors attributed to the capnometer, 36% to RRa, and 18% to both methods.  Events that negatively affected the accuracy of respiration rate included speaking (11 capnometry, 4 RRa), moving (6 capnometry, 1 RRa), and coughing (5 capnometry, 0 RRa).  Comparing the bias of each subject between RRa and capnometry demonstrated limits of agreement for RRa of -1.4 to +1.4 breaths per minute.

Researchers concluded that, "monitoring postoperative respiration rate in extubated patients with an acoustic monitoring device is as accurate as capnometry through an adapted oxygen mask and may be a good alternative to time-consuming clinical assessment. The acoustic sensor was well tolerated while the face mask was removed by eight patients, leading to study discontinuation in two patients. The device appears to be well-tolerated and no more subject to error than capnometry."

Masimo's RRa allows clinicians to noninvasively and continuously assess patients' breathing – facilitating earlier detection of respiratory compromise and patient distress. RRa measures respiration rate using an innovative adhesive sensor with an integrated acoustic transducer that is easily and comfortably applied to the patient's neck.

SOURCE Masimo