Background Respiratory disease is a common reason for hospitalisation and mortality in persons with severe intellectual and developmental disability. Assessment of acute respiratory decompensation and differentiating it from chronic pathology is a frequently encountered challenge. Partial pressure of CO2 is commonly used as an aid in this setting.
Aim To evaluate baseline end tidal CO2 (EtCO2) levels using non-invasive side stream capnometry and to identify factors correlated with higher capnometry readings in this patient population.
Methods This was a prospective, case controlled, cross sectional study to assess differences of baseline EtCO2 values between neurologically impaired patients and healthy individuals. Patient’s demographic and clinical data were recorded. Variables correlating with higher EtCO2 readings and those that may predict clinically meaningful difference among neurologically impaired patients were evaluated.
Results Seventy eight patients and 53 healthy individuals were included. The mean (±SD) EtCO2 values were higher for neurologically impaired patients as compared to healthy individuals (39.14 ± 3.59 and 37.11 ± 1.88 mmHg respectively; p < 0.0001), and highest among patients using antipsychotic medications (41.53 ± 5.257 mmHg). Kyphoscoliosis and the use of antipsychotic drugs were the major factors to increase EtCO2 levels.
Conclusion Knowing the patient’s baseline EtCO2 value, as well as baseline oximetry, could guide treatment decisions, when assessing the patient’s oxygenation and ventilation during acute respiratory illness. Future research can shed light on the utility of capnometry and clinical implications of higher baseline EtCO2 values among neurologically impaired patients.