Use Of Nasal Pressure Research Articles

P045 Noxturnal cRIP: A Comparative Analysis of Sensors for the Identification of Respiratory Events in Polysomnography

Abstract Introduction AASM recommends the use of nasal pressure (NP), oronasal thermal flow (TF), and respiratory inductance plethysmography (RIP) for detecting and characterising respiratory events in polysomnography. The use of both NP and TF sensors is reported to be more accurate in respiratory event identification than either alone. However, these sensors can be unreliable if dislodged and cause discomfort. Noxturnal calibrated RIP flow (cRIPflow), derived from RIP, may provide a non-invasive alternative method for flow measurement in identification of respiratory events. Method Respiratory scoring was performed manually by a single experienced scorer on 10 diagnostic sleep studies under AASM standards. Scoring was repeated using three different measurements for each study: cRIPflow only, Thermistor (Th) only and both Th+NP (AASM recommendation). Apnoea hypopnoea index (AHI), central apnoea index (CAI), obstructive apnoea index (OAI), mixed apnoea index (MAI) and hypopnoea index (HI) were calculated and paired t-test analysis utilised for comparison between measurements. Results No statistical differences were identified in comparison of cRIPflow with Th or Th+NP in respiratory event identification: CAI (cRIPflow 3.2/hr±7.1, Th 3.9/hr±8.9, Th+NP 3.1/hr±7.5), OAI (cRIPflow 6.1/hr±6.8, Th 5.3/hr±8.2, Th+NP 6.7/hr±8.9), MAI (cRIPflow 5.2/hr±9.7, Th 4.3/hr±8.7, Th+NP 4.7/hr±9.2), or HI (cRIPflow 12.5/hr±13.9, Th 11.1/hr±10.5, Th+NP 10.4/hr±10.7). There was a statistical difference for AHI (cRIPflow 26.9/hr±26.6, Th 24.5/hr±26.4, Th+NP 25.0/hr±26.5). Discussion This study suggests cRIPflow may provide an alternative measurement in the detection and characterisation of respiratory events, however further analysis with larger sample size would provide more insight into sensitivity and specificity of this method.

Which OSA Patients Might Respond to Nasal Valves?

Which OSA Patients Might Respond to Nasal Valves?

REMOTE INFRARED IMAGING: A NOVEL NONCONTACT METHOD TO MONITOR AIRFLOW DURING POLYSOMNOGRAPHY

PURPOSE: The use of nasal pressure as the sole monitor for airflow during polysomnography may overestimate disease, especially in mouth breathers. Remote infra-red imaging (IR-I) provides a non-contact method to monitor airflow. Using an infra-red camera placed eight feet from subjects and mathematical modeling, the heat signal from expired air is converted to a signal constituting an airflow channel and is integrated into the existing polysomnographic software as a separate channel. We evaluated the efficacy of IR-I as an alternative airflow channel during polysomnography in comparison with the conventional methods of nasal pressure, nasal-oral thermistors and capnography.

Cognitive Function and Behavior of Children With Adenotonsillar Hypertrophy Suspected of Having Obstructive Sleep-Disordered Breathing

The purpose of this study was to determine whether risks of impaired cognitive function could be predicted for children or groups of children with adenotonsillar hypertrophy who were suspected of having obstructive sleep-disordered breathing, from historical and polysomnographic variables used separately or in combination. We studied 114 consecutive 6- to 12-year-old children with adenotonsillar hypertrophy, who were referred because of suspected obstructive sleep-disordered breathing, with questionnaires, assessment of tonsil size, general and memory cognitive tests, and attended polysomnography with the use of nasal pressure recording to detect flow. There were important significant relationships between snore group (snored every night versus less often), sleep efficiency, and race and 2 of 3 general cognitive tests (vocabulary and similarities). Significant but weaker relationships were observed between sleep latency and 2 memory indices (verbal memory and general memory) and between sleep efficiency and 2 behavior indices (attention-deficit/hyperactivity disorder summary and hyperactive-impulsive summary). The number of episodes of apnea and hypopnea per 1 hour of sleep predicted the vocabulary score as well as did the snore group, but it did not predict other tests as well as other variables. Tonsil size did not predict any cognitive or behavior score. Confidence intervals for group means were small, whereas prediction intervals for individual children were large. Risk of impaired cognitive function and behavior can be predicted from snoring history, sleep efficiency, sleep latency, and race but not tonsil size. The combination of snoring history and polysomnographic variables predicted impaired cognitive scores better than did either alone. The snoring history predicted more test scores than the number of episodes of apnea and hypopnea per 1 hour of sleep.