Usual and Advanced Monitoring in Patients Receiving Oxygen Therapy

Abstract

Respiratory monitoring in patients receiving oxygen therapy for acute care is mandatory at the initial stage of in-hospital management given the potential risk of clinical worsening. Although some patients benefit from close monitoring in the ICU, the vast majority of them are managed in general wards with reduced staff and clinical supervision. The objective of monitoring is to detect early clinical deterioration, which may help prevent in-hospital cardiac arrest. In addition to the clinical and usual evaluations (eg, breathing frequency, breathing pattern, oximetry, and oxygen flow requirements), early warning scoring systems have been developed to detect clinical deterioration in acutely ill patients. The monitoring of these scores is recommended for patients receiving oxygen therapy. These scores have several limitations, among which is the absence of oxygen flow evaluation. Manual and intermittent monitoring of these scores in the ward is time-consuming and may not be sufficient to accurately detect deterioration of patient’s clinical condition in a timely manner. Automated and continuous monitoring, in addition to clinical evaluation and arterial blood gases analysis, which remain necessary, may improve the detection of clinical worsening in specific patients. Devices that automatically titrate and wean oxygen flow on the basis of ${\mathbf{\text{S}}}_{{\mathbf{\text{pO}}}_{\mathbf{\text{2}}}}$ enable measurement of several major cardiorespiratory parameters (eg, ${\mathbf{\text{S}}}_{{\mathbf{\text{pO}}}_{\mathbf{\text{2}}}}$ , oxygen flow, heart rate, breathing frequency, and heart rate variability). The combination of these parameters into new scores is at least as accurate and well-evaluated, and recommended early warning scores and may be useful in monitoring patients receiving oxygen therapy.