Accuracy of a New Low-flow Sidestream Capnography Technology in Newborns: A Pilot Study

Abstract

Low-flow capnography with Microstream technology accurately measured alveolar CO(2) in newborns without pulmonary disease, as demonstrated by normal PetCO(2)-PaCO(2) gradients. The measured PetCO(2)-PaCO(2) gradient, as expected, was significantly higher in newborns with pulmonary disease. We also identified four quantitative waveform parameters that may be useful in differentiating between mechanically ventilated newborn patients with and without lung disease.

Classical Respiratory Monitoring

“…Due to the strong correlation between P a − et CO 2 and alveolar dead space, these authors state that from a clinical perspective, measuring P a − et CO 2 to monitor NO inhalation therapy is simpler than measuring alveolar dead space as an ordinary end-tidal CO 2 monitor can substitute for a sophisticated system of dead space measurements requiring simultaneous measurements of CO 2 elimination and tidal volume. Hagerty et al (2002) found a higher P a − et CO 2 gradient when comparing newborns with pulmonary disease and those who received mechanical ventilation for non-pulmonary conditions. However, McDonald et al (2002) showed in a large study in 129 ventilated infants using 2,184 arterial blood and gas samples that in most of the patients, P a − et CO 2 is small enough such that P et CO 2 monitoring enables the clinician to adequately monitor ventilation and gas exchange.…”

“…In neonates with a minute ventilation of about 200 mL/min/kg body weight, the suction flow must be sufficiently low to prevent dilution by surrounding air that will occur when the expiratory gas flow rate falls below the suction flow rate. A microstream capnograph using a suction flow of 30 mL/min and a miniaturized sample chamber has been developed, thus, improving the measurement accuracy for intubated infants (Hagerty et al 2002;Kugelman et al 2008).…”

Agreement between arterial partial pressure of carbon dioxide and saturation of hemoglobin with oxygen values obtained by direct arterial blood measurements versus noninvasive methods in conscious healthy and ill foals

“…3,4,21,22 Clinically, the Paco 2 -Petco 2 gradient can be used to document and monitor a variety of respiratory or cardiac conditions. [24][25][26][27][28] For example, neonatal infants with pulmonary disorders such as persistent pulmonary hypertension, respiratory distress syndrome, pneumonia, or meconium aspiration had a significantly higher Paco 2 -Petco 2 gradient (7.4 ± 3.3 mm Hg) when compared with aged-matched healthy controls (3.0 ± 2.4 mm Hg). 25 The Paco 2 -Petco 2 gradient has also been used to support the diagnosis of pulmonary thromboembolism as well as to monitor efficacy of thrombolysis in patients with pulmonary thromboembolism.…”

“…[24][25][26][27][28] For example, neonatal infants with pulmonary disorders such as persistent pulmonary hypertension, respiratory distress syndrome, pneumonia, or meconium aspiration had a significantly higher Paco 2 -Petco 2 gradient (7.4 ± 3.3 mm Hg) when compared with aged-matched healthy controls (3.0 ± 2.4 mm Hg). 25 The Paco 2 -Petco 2 gradient has also been used to support the diagnosis of pulmonary thromboembolism as well as to monitor efficacy of thrombolysis in patients with pulmonary thromboembolism. 27,28 Therefore, the Paco 2 -Petco 2 gradient can be used to evaluate or monitor progression of various pulmonary or cardiovascular diseases.…”

PETCO2 measured by a new lightweight mainstream capnometer with very low dead space volume offers accurate and reliable noninvasive estimation of PaCO2

“…Furthermore, relative inaccuracy is seen in conditions of ventilationperfusion mismatch. 18,19 Transcutaneous CO 2 monitoring is a noninvasive technique for measuring CO 2 levels. However, transcutaneous CO 2 monitoring is not tolerated in very low birth weight infants because of their fragile skin, and the technique is affected by acidosis and hypoxia.…”