Oxygraphy: an unexplored perioperative monitoring modality

State of the art: Monitoring of the respiratory system during veno-venous extracorporeal membrane oxygenation

Monitoring the patient receiving veno-venous extracorporeal membrane oxygenation (VV ECMO) is challenging due to the complex physiological interplay between native and membrane lung. Understanding these interactions is essential to understand the utility and limitations of different approaches to respiratory monitoring during ECMO. We present a summary of the underlying physiology of native and membrane lung gas exchange and describe different tools for titrating and monitoring gas exchange during ECMO. However, the most important role of VV ECMO in severe respiratory failure is as a means of avoiding further ergotrauma. Although optimal respiratory management during ECMO has not been defined, over the last decade there have been advances in multimodal respiratory assessment which have the potential to guide care. We describe a combination of imaging, ventilator-derived or invasive lung mechanic assessments as a means to individualise management during ECMO.

Not All Oxygrams Are Mirror Image of Capnograms: A Case Report

Generally the oxygram and the capnogram are mirror images of each other. We report a situation where a leak in the sample line produced a typical tails-up capnogram that was not accompanied by a mirror image oxygram. Air entrainment through the breach led to dilution of the gases on their way to the analyzer. The result was an oxygram resembling a series of mountain peaks.

Accurate and stable continuous monitoring module by mainstream capnography

End-tidal partial pressure of [Formula: see text] is an important index in clinical monitoring. Medical mainstream capnography has become widely used, but there are still limitations in accuracy and stability. A type of mainstream capnometer based on the principle of non-dispersive infrared was designed. This capnometer inhibits signal drift by using electric modulation and thus ensures the accuracy of long-term CO2 monitoring. Statistical methods are used to find the best setting for sampling respiratory signals and improving precision. Several digital filtering techniques are used to process various interferences and improve capnogram quality. Clinical tests and targeted experiments show this mainstream capnometer can accurately monitor respiratory CO2 concentrations, especially at the end-tidal peak point. This capnometer also shows high accuracy and stability in long-term continuous monitoring.