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Critical Care (London, England) Jul 2015Pulse oximetry is universally used for monitoring patients in the critical care setting. This article updates the review on pulse oximetry that was published in 1999 in... (Review)
Review
Pulse oximetry is universally used for monitoring patients in the critical care setting. This article updates the review on pulse oximetry that was published in 1999 in Critical Care. A summary of the recently developed multiwavelength pulse oximeters and their ability in detecting dyshemoglobins is provided. The impact of the latest signal processing techniques and reflectance technology on improving the performance of pulse oximeters during motion artifact and low perfusion conditions is critically examined. Finally, data regarding the effect of pulse oximetry on patient outcome are discussed.
Topics: Critical Care; Critical Illness; Humans; Monitoring, Physiologic; Oximetry
PubMed: 26179876
DOI: 10.1186/s13054-015-0984-8 -
Journal of Cardiothoracic and Vascular... Aug 2022THE USE OF NEAR-INFRARED SPECTROSCOPY (NIRS) has increased significantly worldwide in the past decade. This technology, first described more than 40 years ago, is based... (Review)
Review
THE USE OF NEAR-INFRARED SPECTROSCOPY (NIRS) has increased significantly worldwide in the past decade. This technology, first described more than 40 years ago, is based on the fact that near-infrared light is able to penetrate biologic tissue and can obtain real-time, noninvasive information on tissue oxygenation and metabolism. In the clinical setting, NIRS has been able to provide clinicians potentially valuable information in patients with impaired microcirculations (systemic and cerebral). Near-infrared spectroscopy has progressed beyond assessment of brain oxygenation to monitor local tissue and muscle oxygenation and perfusion. This review analyzes the published data and provides the clinician a comprehensive account of the perioperative utility of NIRS in cardiac, vascular and thoracic surgery, as well as its increasing role in tissue/muscle oxygenation monitoring.
Topics: Brain; Humans; Monitoring, Physiologic; Oximetry; Oxygen; Spectroscopy, Near-Infrared; Thoracic Surgery
PubMed: 34362641
DOI: 10.1053/j.jvca.2021.07.015 -
Respiratory Care Jun 2020Critical illness can threaten the adequacy of O delivery or CO excretion. Monitoring seeks to identify the adequacy of oxygenation and ventilation and to detect... (Review)
Review
Critical illness can threaten the adequacy of O delivery or CO excretion. Monitoring seeks to identify the adequacy of oxygenation and ventilation and to detect deterioration early. Advances in oximetry, capnography, and transcutaneous CO monitoring offer new opportunities for more accurate estimation of gas exchange, noninvasive monitoring of parameters previously not amenable (eg, total hemoglobin measurement), detection of disease, and prediction of fluid responsiveness.
Topics: Blood Gas Monitoring, Transcutaneous; Capnography; Critical Illness; Humans; Monitoring, Physiologic; Oximetry
PubMed: 32457167
DOI: 10.4187/respcare.07408 -
European Journal of Anaesthesiology Dec 2018Cerebral near-infrared spectroscopy (NIRS) of tissue oxygen saturation is claimed to be a surrogate marker for global cerebral perfusion. Increasingly, NIRS target-based... (Observational Study)
Observational Study
BACKGROUND
Cerebral near-infrared spectroscopy (NIRS) of tissue oxygen saturation is claimed to be a surrogate marker for global cerebral perfusion. Increasingly, NIRS target-based therapy has been used during cardiac surgery in the hope of decreasing the incidence of adverse neurological outcome.
OBJECTIVES
We report NIRS values for some common vegetables and faculty at a world-class medical institution.
DESIGN
Observational nonblinded study.
SETTING
Single tertiary care institution and local urban vegetable market.
PARTICIPANTS
Five yams (Dioscorea cayenensis), five courgettes (Cucurbita pepo) and five butternut squashes (Cucurbita moschata) were studied. Five cardiothoracic surgeons and anaesthesiologists were the control group.
INTERVENTIONS
None.
MAIN OUTCOME MEASURES
NIRS value of each species.
RESULTS
Mean NIRS value for the control group was 71% [95% confidence interval (CI) 68 to 74] and was similar to that of the yellow squashes [75% (95% CI 74 to 76)]. These values were significantly greater than the NIRS measurements of both the butternut squash and yam [63% (95% CI 62 to 64) and 64% (95% CI 63 to 65), respectively, P < 0.01].
CONCLUSION
Commonly eaten vegetables have NIRS measurements similar to those seen in healthy humans.
Topics: Brain; Female; Humans; Male; Oximetry; Spectroscopy, Near-Infrared; Vegetables
PubMed: 30020143
DOI: 10.1097/EJA.0000000000000855 -
BMC Medicine Aug 2022During the COVID-19 pandemic, there have been concerns regarding potential bias in pulse oximetry measurements for people with high levels of skin pigmentation. We... (Meta-Analysis)
Meta-Analysis
BACKGROUND
During the COVID-19 pandemic, there have been concerns regarding potential bias in pulse oximetry measurements for people with high levels of skin pigmentation. We systematically reviewed the effects of skin pigmentation on the accuracy of oxygen saturation measurement by pulse oximetry (SpO) compared with the gold standard SaO measured by CO-oximetry.
METHODS
We searched Ovid MEDLINE, Ovid Embase, EBSCO CINAHL, ClinicalTrials.gov, and WHO International Clinical Trials Registry Platform (up to December 2021) for studies with SpO-SaO comparisons and measuring the impact of skin pigmentation or ethnicity on pulse oximetry accuracy. We performed meta-analyses for mean bias (the primary outcome in this review) and its standard deviations (SDs) across studies included for each subgroup of skin pigmentation and ethnicity and used these pooled mean biases and SDs to calculate accuracy root-mean-square (A) and 95% limits of agreement. The review was registered with the Open Science Framework ( https://osf.io/gm7ty ).
RESULTS
We included 32 studies (6505 participants): 15 measured skin pigmentation and 22 referred to ethnicity. Compared with standard SaO measurement, pulse oximetry probably overestimates oxygen saturation in people with the high level of skin pigmentation (pooled mean bias 1.11%; 95% confidence interval 0.29 to 1.93%) and people described as Black/African American (1.52%; 0.95 to 2.09%) (moderate- and low-certainty evidence). The bias of pulse oximetry measurements for people with other levels of skin pigmentation or those from other ethnic groups is either more uncertain or suggests no overestimation. Whilst the extent of mean bias is small or negligible for all subgroups evaluated, the associated imprecision is unacceptably large (pooled SDs > 1%). When the extent of measurement bias and precision is considered jointly, pulse oximetry measurements for all the subgroups appear acceptably accurate (with A < 4%).
CONCLUSIONS
Pulse oximetry may overestimate oxygen saturation in people with high levels of skin pigmentation and people whose ethnicity is reported as Black/African American, compared with SaO. The extent of overestimation may be small in hospital settings but unknown in community settings. REVIEW PROTOCOL REGISTRATION: https://osf.io/gm7ty.
Topics: COVID-19; Humans; Oximetry; Oxygen; Oxygen Saturation; Pandemics; Skin Pigmentation
PubMed: 35971142
DOI: 10.1186/s12916-022-02452-8 -
Journal of Clinical Monitoring and... Feb 2021From home to intensive care units, innovations in pulse oximetry are susceptible to improve the monitoring and management of patients developing acute respiratory...
From home to intensive care units, innovations in pulse oximetry are susceptible to improve the monitoring and management of patients developing acute respiratory failure, and particularly those with the coronavirus disease 2019 (COVID-19). They include self-monitoring of oxygen saturation (SpO) from home, continuous wireless SpO monitoring on hospital wards, and the integration of SpO as the input variable for closed-loop oxygen administration systems. The analysis of the pulse oximetry waveform may help to quantify respiratory efforts and prevent intubation delays. Tracking changes in the peripheral perfusion index during a preload-modifying maneuver may be useful to predict preload responsiveness and rationalize fluid therapy.
Topics: COVID-19; Critical Care; Fluid Therapy; Home Care Services; Humans; Monitoring, Ambulatory; Monitoring, Physiologic; Oximetry; Oxygen; Oxygen Inhalation Therapy; Pandemics; Respiratory Insufficiency; SARS-CoV-2; Work of Breathing
PubMed: 32578070
DOI: 10.1007/s10877-020-00550-7 -
Resuscitation Dec 2014
Topics: Cardiopulmonary Resuscitation; Drama; Heart Arrest; Humans; Oximetry; Spectroscopy, Near-Infrared; Television
PubMed: 25291253
DOI: 10.1016/j.resuscitation.2014.09.024 -
Pediatrics in Review Nov 2019
Topics: Equipment Design; Heart Defects, Congenital; Humans; Hypoxia; Infant, Newborn; Neonatal Screening; Oximetry
PubMed: 31676537
DOI: 10.1542/pir.2018-0123 -
Anesthesia and Analgesia Jan 2017A number of different technologies have been developed to measure tissue oxygenation, with the goal of identifying tissue hypoxia and guiding therapy to prevent patient... (Review)
Review
A number of different technologies have been developed to measure tissue oxygenation, with the goal of identifying tissue hypoxia and guiding therapy to prevent patient harm. In specific cases, tissue oximetry may provide clear indications of decreases in tissue oxygenation such as that occurring during acute brain ischemia. However, the causation between tissue hemoglobin-oxygen desaturation in one organ (eg, brain or muscle) and global outcomes such as mortality, intensive care unit length of stay, and remote organ dysfunction remains more speculative. In this review, we describe the current state of evidence for predicting clinical outcomes from tissue oximetry and identify several issues that need to be addressed to clarify the link between tissue oxygenation and outcomes. We focus primarily on the expanding use of near-infrared spectroscopy to assess a venous-weighted mixture of venous and arterial hemoglobin-oxygen saturation deep in tissues such as brain and muscle. Our analysis finds that more work is needed in several areas: establishing threshold prediction values for tissue desaturation-related injury in specific organs, defining the types of interventions required to correct changes in tissue oxygenation, and defining the effect of interventions on outcomes. Furthermore, well-designed prospective studies that test the hypothesis that monitoring oxygenation status in one organ predicts outcomes related to other organs need to be done. Finally, we call for more work that defines regional variations in tissue oxygenation and improves technology for measuring and even imaging oxygenation status in critical organs. Such studies will contribute to establishing that monitoring and imaging of tissue oxygenation will become routine in the care of high-risk patients because the monitors will provide outputs that direct therapy to improve clinical outcomes.
Topics: Biomarkers; Equipment Design; Humans; Hypoxia; Monitoring, Intraoperative; Oximetry; Oxygen; Oxygen Consumption; Oxyhemoglobins; Predictive Value of Tests; Prognosis; Reproducibility of Results; Risk Factors; Surgical Procedures, Operative
PubMed: 27308951
DOI: 10.1213/ANE.0000000000001348 -
Sensors (Basel, Switzerland) Aug 2020Adequate oxygen delivery to a tissue depends on sufficient oxygen content in arterial blood and blood flow to the tissue. Oximetry is a technique for the assessment of... (Review)
Review
Adequate oxygen delivery to a tissue depends on sufficient oxygen content in arterial blood and blood flow to the tissue. Oximetry is a technique for the assessment of blood oxygenation by measurements of light transmission through the blood, which is based on the different absorption spectra of oxygenated and deoxygenated hemoglobin. Oxygen saturation in arterial blood provides information on the adequacy of respiration and is routinely measured in clinical settings, utilizing pulse oximetry. Oxygen saturation, in venous blood (SvO) and in the entire blood in a tissue (StO), is related to the blood supply to the tissue, and several oximetric techniques have been developed for their assessment. SvO can be measured non-invasively in the fingers, making use of modified pulse oximetry, and in the retina, using the modified Beer-Lambert Law. StO is measured in peripheral muscle and cerebral tissue by means of various modes of near infrared spectroscopy (NIRS), utilizing the relative transparency of infrared light in muscle and cerebral tissue. The primary problem of oximetry is the discrimination between absorption by hemoglobin and scattering by tissue elements in the attenuation measurement, and the various techniques developed for isolating the absorption effect are presented in the current review, with their limitations.
Topics: Humans; Monitoring, Physiologic; Oximetry; Oxygen; Spectroscopy, Near-Infrared
PubMed: 32867184
DOI: 10.3390/s20174844