ABSTRACT:
End-tidal carbon dioxide (EtCO2) measurement is an intriguing technology because it is non-invasive, portable, and reasonably inexpensive. The method has been widely used in the adult and paediatric intensive care settings, and it has been shown to be an accurate method of estimating PaCO2 in term infants; however, it has not been widely accepted in the NICU because it only provides a rough estimate of PaCO2 in infants with remarkable lung function. EtCO2 detectors determine the amount of carbon dioxide in exhaled breath. EtCO2 is carbon dioxide at its peak concentration at the end of expiration. A good end-tidal plateau in exhaled PaCO2 typically represents alveolar PaCO2, which is easily measurable in adults and older children with large tidal volumes. However, this can be strenuous in sick neonates who frequently have a fast respiratory rate. The carbon dioxide can be calculated by chemical response, referred to as calorimetry or actual measurement of carbon dioxide molecules. 1 The latter method is a better metric in intensive care since it delivers a numerical value. Carbon dioxide monitors are classified into two types: capnometers and capnographs, which employ infrared absorption or mass spectrometry to measure carbon dioxide and display the result in mmHg or percentage of carbon dioxide. The capnometer displays EtCO2 values, whereas the capnograph, which monitors carbon dioxide during each inspiratory/expiratory cycle, shows both a waveform and a numerical number 2. Capnometry, which measures the concentration of carbon dioxide (CO2) in the atmosphere, was originally employed during World War II to monitor the interior environment. It was originally used in medicine in 1950 to monitor the amount of CO2 exhaled during anaesthesia. However, it was not employed in practice until the early 1980s, when capnometry made its official debut in the anaesthesiology area with the introduction of smaller devices. There are two sorts of capnographs: "side stream" and "mainstream". The "mainstream" technique uses a sample window in the ventilator circuit to measure CO2, whereas the "side stream" technique uses a gas analyser outside of the ventilator circuit. Both types of gas analysers use infrared light, mass or Raman spectra, and photoacoustic spectra technology. The volumetric capnograph makes use of flow measurement equipment 3.