2005 OPEN FORUM Abstracts
Continuous Monitoring of Volumetric Capnography ReDuces Length of Mechanical Ventilation in a Heterogeneous Group of Pediatric ICU Patients
Donna Hamel, RRT, RCP, FAARC; Ira Cheifetz, MD, FAARC; Pediatric Critical Care Medicine, Duke Children's Hospital, Durham, North Carolina
Background: Complications result from mechanical ventilation even under the best of circumstances; therefore, careful consideration must be provided for optimal management strategies on a continual basis. Recent advances in technology provide clinicians access to noninvasive monitoring devices with the ability to display measurable and consistent data, thus, allowing for a more objective approach to total ventilator management.
Volumetric capnography displays breath-by-breath measurements of exhaled carbon dioxide during the entire respiratory cycle. Additionally, the integration of flow and carbon dioxide elimination over time enables the capnograph to calculate and display alveolar minute ventilation (MVALV) and deadspace ventilation (Vd/Vt). Therefore, volumetric capnography should be a better marker for monitoring dynamic changes in gas exchange during mechanical ventilation than standard time-based capnometry alone.
Hypothesis: We hypothesized that the management of patients using continuous volumetric capnography, including monitoring of the deadspace to tidal volume ratio, alveolar minute ventilation, and carbon dioxide elimination (VCO2), would reduce the length of ventilation (LOV) in infants and children.
Methods: All mechanically ventilated PICU patients (0-18 years of age) were eligible for enrollment in this prospective, randomized study. Intervention patients were placed on a NICO Respiratory Profile Monitor (Respironics, Inc.) on initiation of mechanical ventilation in our Pediatric ICU. These patients remained on the NICO Monitor until extubation. Control patients received all standard care and monitoring including intermittent use of volumetric capnography at the discretion of the PICU team.
Results: Both the parametric t-test and the non-parametric Wilcoxon test reflect a statistically significant difference in average length of ventilation with LOV being significantly reduced for the NICO group. Patients managed with continuous volumetric capnography (n=99) had a significantly shorter LOV than control patients (n=99) (117.3 vs. 171.4 hrs; p = 0.002). Extubation failure rates were similar for both groups.
Conclusion: Length of ventilation in a heterogeneous group of pediatric patients was decreased by 2.25 days, a clinically significant 32%, with the use of Vd/Vt, MVALV, and VCO2 monitoring. Such a significant decrease in LOV should correlate with a reduction in length of ICU admission, cost, complications, and morbidity as well as improved patient and family satisfaction.