Correlation Between the Integrated Pulmonary Index (IPI) and Arterial Blood Gases in a Medical-Surgical ICU in Saudi Arabia


      SESSION TITLE: Critical Care
      SESSION TYPE: Slide Presentations
      PRESENTED ON: Monday, March 24, 2014 at 10:45 AM - 11:45 AM
      PURPOSE: Arterial blood gases are routinely obtained to monitor adequacy of oxygenation, ventilation, and acid-base status in patients undergoing mechanical ventilation. A novel respiratory index, the Integrated Pulmonary Index, (IPI™), was developed to provide a simple and accurate tool to assess respiratory status and to assist in determining if an intervention is necessary. Through a mathematical algorithm that integrates respiratory rate (RR), end-tidal CO2 (etCO2), pulse rate (PR), and pulse oxygen saturation (SpO2), the IPI is continuously displayed as a number between 1 and 10, where 8 to 10 indicates a normal overall respiratory status, 5 to 7 indicates needs for assessment and possible intervention, and 1 to 4 calls for prompt intervention. Although IPI has been shown to correlate well with respiratory status in adults and children undergoing procedural sedation, it has not yet been correlated with arterial blood gas parameters obtained in the intensive care unit (ICU). This study evaluated the clinical correlation between the IPI and results from arterial blood gases routinely obtained in the ICU.
      METHODS: We prospectively recorded the value of the IPI (Capnostream 20, Oridion Capnography, Inc.) from 21 patients who were mechanically ventilated in a medical and surgical ICU at the National Guard Health Affairs in Riyadh, Saudi Arabia. The IPI was documented every two hours as part of the routine patient-ventilator “check”. A total of 64 patient-ventilator “checks” (events) were selected for analysis as they were the only ones containing both the IPI and arterial blood gas values within the same clock hour. The RR, FiO2, PaO2/FiO2 ratio and SaO2/FiO2 ratios were also recorded and compared to the IPI. Descriptive statistics were obtained using SPSS 19.0 (Chicago, IL).
      RESULTS: The mean IPI for the 64 events analyzed was 8.1+/-1.8. The mean values for the respiratory rate and ABG values were within normal limits (RR: 21.2 + 4.3; PaCO2: 43.26 + 9.08 mm Hg; PaO2: 94.29 + 28.75 mm Hg; SaO2 97.28% + 1.57; FIO2:.38 +.11; PaO2/FiO2=260 + 77).
      CONCLUSIONS: On this group of patients, the IPI was consistent with the interpretation of the respiratory status reflected by the ABG values. Although the mean PaO2/FiO2 and the RR were close to what clinicians may consider acceptable values, they may have prevented the IPI from displaying an even higher value.
      CLINICAL IMPLICATIONS: The IPI has a potential to become a more dynamic measurement of the overall respiratory status than the arterial blood gas.
      DISCLOSURE: Ruben Restrepo: Grant monies (from industry related sources): Received funding from Covidien to complete this investigator-initiated project The following authors have nothing to disclose: Adil Alotaibi
      Although the equipment used for monitoring capnography and pulse oximetry (Capnostream), the IPI is still under investigation for vaildation as a pulmonary index.