Imputation of partial pressures of arterial oxygen using oximetry and its impact on sepsis diagnosis.


OBJECTIVE:The ratio of the partial pressure of arterial oxygen to fraction of inspired oxygen is a key component of the sequential organ failure assessment score that operationally defines sepsis. But, it is calculated infrequently due to the need for the acquisition of an arterial blood gas. So, we sought to find an optimal imputation strategy for the estimation of sepsis-defining hypoxemic respiratory failure using oximetry instead of an arterial blood gas. APPROACH:We retrospectively studied a sample of non-intubated acute-care patients with oxygen saturation recorded  ⩽10 min before arterial blood sampling (N  =  492 from 2013-2017). We imputed ratios of the partial pressure of arterial oxygen to the fraction of inspired oxygen and sepsis criteria from existing imputation equations (Hill, Severinghaus-Ellis, Rice, and Pandharipande) and compared them with the ratios and sepsis criteria measured from arterial blood gases. We devised a modified model-based equation to eliminate the bias of the results. MAIN RESULTS:Hypoxemia severity estimates from the Severinghaus-Ellis equation were more accurate than those from other existing equations, but showed significant proportional bias towards under-estimation of hypoxemia severity, especially at oxygen saturations  >96%. Our modified equation eliminated bias and surpassed others on all imputation quality metrics. SIGNIFICANCE:Our modified imputation equation, [Formula: see text] is the first one that is free of bias at all oxygen saturations. It resulted in ratios of partial pressure of arterial oxygen to fraction of inspired oxygen and sepsis respiratory criteria closest to those obtained by arterial blood gas testing and is the optimal imputation strategy for non-intubated acute-care patients.


Physiol Meas


Gadrey SM,Lau CE,Clay R,Rhodes GT,Lake DE,Moore CC,Voss JD,Moorman JR




Has Abstract


2019-12-03 00:00:00












  • Validity and reliability of a timed 5 km cycle ergometer ride to predict maximum oxygen uptake.

    abstract::The purpose of this study was to determine the validity and reliability of a timed 5 km cycle ergometer ride to predict maximum oxygen uptake (VO2max). Fifty-two healthy volunteers had their VO2max determined during a maximal treadmill run. They also performed a timed 5 km cycle ergometer ride. The resistance setting ...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章,随机对照试验


    authors: Buono MJ,Borin TL,Sjoholm NT,Hodgdon JA

    更新日期:1996-11-01 00:00:00

  • In vivo quantification of accumulating abdominal fluid using an electrical impedance tomography hemiarray.

    abstract::A new method to image and quantify intra-abdominal haemorrhage using electrical impedance tomography (EIT) was tested in vivo. Supine peritoneal dialysis patients were monitored using an 8-electrode hemiarray placed on the anterior abdomen. EIT measurements were recorded using the EPack II data acquisition system befo...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Tucker AS,Ross EA,Paugh-Miller J,Sadleir RJ

    更新日期:2011-02-01 00:00:00

  • Assessment of the dynamic interactions between heart rate and arterial pressure by the cross time-frequency analysis.

    abstract::In this study, a framework for the characterization of the dynamic interactions between RR variability (RRV) and systolic arterial pressure variability (SAPV) is proposed. The methodology accounts for the intrinsic non-stationarity of the cardiovascular system and includes the assessment of both the strength and the p...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Orini M,Laguna P,Mainardi LT,Bailón R

    更新日期:2012-03-01 00:00:00

  • Ischemic small intestine-in vivo versus ex vivo bioimpedance measurements.

    abstract:OBJECTIVE:Bioimpedance has been used to investigate changes in electrical parameters during ischemia in various tissues. The small intestine is a multi-layered structure, with several distinct tissue types, and ischemia related changes occur at different times in the different intestinal layers. When investigating how ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Strand-Amundsen RJ,Reims HM,Tronstad C,Kalvøy H,Martinsen ØG,Høgetveit JO,Ruud TE,Tønnessen TI

    更新日期:2017-05-01 00:00:00

  • Treading on the unknown-the feasibility of a novel approach to investigating the motor control of walking.

    abstract:BACKGROUND AND OBJECTIVE:Walking is a complex human behavior, usually performed in a dynamic environment. Gait parameters are thought to reflect this complexity. Re-Step™ is a therapy system in the form of a computerized shoe, originally developed for the training and rehabilitation of individuals with brain damage. Th...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Koren Y,Raanan Y,Parmet Y,Bar-Haim S

    更新日期:2018-04-26 00:00:00

  • Hidden Markov model-based activity recognition for toddlers.

    abstract:OBJECTIVE:Physical activity has been shown to impact future health outcomes in adults, but little is known about the long-term impact of physical activity in toddlers. Accurately measuring the specific types and amounts of physical activity in toddlers will help us to understand, predict, and better affect their future...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Albert MV,Sugianto A,Nickele K,Zavos P,Sindu P,Ali M,Kwon S

    更新日期:2020-03-06 00:00:00

  • Comparison of macro- and micro-lightguide spectrophotometric measurements of microvascular haemoglobin oxygenation in the tuberculin reaction in normal human skin.

    abstract::The changes in haemoglobin oxygenation (SO2) occurring in the tuberculin reaction in human skin were measured using macro- and micro-lightguide spectrophotometry and the results compared. A significant difference was found between the measurements from the respective instruments, demonstrating that the micro-lightguid...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Newton DJ,Harrison DK,Delaney CJ,Beck JS,McCollum PT

    更新日期:1994-05-01 00:00:00

  • Specific heat capacity of freshly excised prostate specimens.

    abstract::The specific heat capacity of tissue is a critical parameter for thermal therapies that act over a long period of time. It is also critical for thermoacoustic signal generation. We present ex vivo measurements of specific heat capacity performed by a dual-pin probe with tight temperature control of the specimen. One 3...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Patch SK,Rao N,Kelly H,Jacobsohn K,See WA

    更新日期:2011-11-01 00:00:00

  • Monitoring nasal conductance by bilateral nasal cannula pressure transducers.

    abstract::Nasal obstruction is common and may disturb well-being during daytime and sleep. Its objective assessment by standard methods requires patient cooperation and inconvenient instrumentation. Therefore, the purpose of this study was to develop a novel, unobtrusive technique for continuous monitoring of changes in nasal c...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Thurnheer R,Bloch KE

    更新日期:2004-04-01 00:00:00

  • Evaluation of an algorithm based on single-condition decision rules for binary classification of 12-lead ambulatory ECG recording quality.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Di Marco LY,Duan W,Bojarnejad M,Zheng D,King S,Murray A,Langley P

    更新日期:2012-09-01 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Bayford RH,Gibson A,Tizzard A,Tidswell T,Holder DS

    更新日期:2001-02-01 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Bai Y,Liang Z,Li X,Voss LJ,Sleigh JW

    更新日期:2015-12-01 00:00:00

  • Design considerations and performance of a prototype system for imaging neuronal depolarization in the brain using 'direct current' electrical resistance tomography.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Boone KG,Holder DS

    更新日期:1995-08-01 00:00:00

  • Electroencephalography as a predictor of self-report fatigue/sleepiness during monotonous driving in train drivers.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Lees T,Chalmers T,Burton D,Zilberg E,Penzel T,Lal S,Lal S

    更新日期:2018-10-30 00:00:00

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    abstract::Nasal obstruction disturbs comfort during daytime, and sleep quality. Convenient objective assessment of nasal ventilation would be desirable. Therefore, we developed a technique for unobtrusive monitoring of bilateral nasal airflow. Nasal cannulae with separated left- and right-sided tubings were connected to two pre...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Kohler M,Thurnheer R,Bloch KE

    更新日期:2005-02-01 00:00:00

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    abstract:OBJECTIVE:U-shaped patterns, characteristic periods of time observed in tachograms, are a specific subgroup among very low frequency components characterized by relatively short periods of smooth accelerations followed by decelerations of heart rhythm. In this study, we characterize this phenomenon and its effect on he...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Soliński M,Kuklik P,Gierałtowski J,Baranowski R,Graff B,Żebrowski J

    更新日期:2020-07-02 00:00:00

  • Empirical estimators of gamma fits to tracer-dilution curves and their technical basis and practical scope.

    abstract::A gamma fit facilitates smoothing and extrapolation of distorted tracer-dilution curves in blood flow studies. Theoretically based empirical estimators were developed as simple alternatives to direct regression approaches from simulated gamma distributions with a wide range of shape asymmetry. Key curve features of pe...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Lopatatzidis A,Millard RK

    更新日期:2001-11-01 00:00:00

  • EITS changes following oleic acid induced lung water.

    abstract::We present the results of using electrical impedance tomographic spectroscopy (EITS) to follow the changes in lung water induced by oleic acid. Measurements were made on three goats before and after the injection of oleic acid. In addition to the EITs measurements, lung water was also measured using a double-indicator...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Brown BH,Flewelling R,Griffiths H,Harris ND,Leathard AD,Lu L,Morice AH,Neufeld GR,Nopp P,Wang W

    更新日期:1996-11-01 00:00:00

  • Time variation of ammonia, acetone, isoprene and ethanol in breath: a quantitative SIFT-MS study over 30 days.

    abstract::A study of the concentrations of the common breath metabolites ammonia, acetone, isoprene, ethanol and acetaldehyde in the breath of five subjects over a period of 30 days has been carried out. Breath samples were taken and analysed in the early morning on arrival at the laboratory. The real time analyses of three con...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Diskin AM,Spanel P,Smith D

    更新日期:2003-02-01 00:00:00

  • A method of reducing the error caused by boundary shape and electrode positions in electrical impedance tomography.

    abstract::This paper describes a method of reducing the influence of the data error caused by non-ideal boundary shape and electrode placement on reconstructed images. A data calibration and a modified Newton-Raphson reconstruction are combined in the method to ensure rapid convergence and small reconstruction error. The method...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Li J

    更新日期:1994-05-01 00:00:00

  • Time-related heart autonomic balance characteristics in healthy subjects.

    abstract::Changes of the heart autonomic balance between morning (8-9 h) and afternoon (14-15 h) measurements were studied in 22 healthy subjects. The selection of these two daytime periods was substantiated by the established higher risk of cardiovascular incidents in the morning and the relative balance of the vegetative nerv...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Matveev M,Prokopova R,Nachev Ch

    更新日期:2003-08-01 00:00:00

  • Topographic distribution of idiopathic pulmonary fibrosis: a hybrid physics- and agent-based model.

    abstract:OBJECTIVE:Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease characterized by excessive deposition of collagen and associated stiffening of lung tissue. While it is known that inflammation and dysfunction of fibroblasts are involved in disease development, it remains poorly understood how cells and ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Wellman TJ,Mondoñedo JR,Davis GS,Bates JHT,Suki B

    更新日期:2018-06-28 00:00:00

  • Classification of glucose concentration in diluted urine using the low-resolution Raman spectroscopy and kernel optimization methods.

    abstract::In order to detect minute amounts of glucose in diluted urine, we applied the Raman spectroscopy method. To simulate abnormal diluted urine in a toilet bowl, we diluted normal urine ten-fold with water and added glucose up to 8 mg dl(-1). Data were collected using a low-resolution Raman spectrometer that was preproces...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Park C,Kim K,Choi J,Park K

    更新日期:2007-05-01 00:00:00

  • A novel method for continuous blood pressure estimation based on a single-channel photoplethysmogram signal.

    abstract:OBJECTIVE:Currently, continuous blood pressure (BP) measurements are mostly based on multi-sensor combinations and datasets with limited BP ranges. Besides, most BP-related features derive from the photoplethysmogram (PPG) signal. The mechanism of PPG signal formation is not considered. We aimed to design a noninvasive...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Hu Q,Deng X,Wang A,Yang C

    更新日期:2021-01-01 00:00:00

  • An automated quasi-continuous capillary refill timing device.

    abstract::Capillary refill time (CRT) is a simple means of cardiovascular assessment which is widely used in clinical care. Currently, CRT is measured through manual assessment of the time taken for skin tone to return to normal colour following blanching of the skin surface. There is evidence to suggest that manually assessed ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Blaxter LL,Morris DE,Crowe JA,Henry C,Hill S,Sharkey D,Vyas H,Hayes-Gill BR

    更新日期:2016-01-01 00:00:00

  • PaCO2 measurement in cerebral haemodynamics: face mask or nasal cannulae?

    abstract:OBJECTIVE:PaCO2 affects cerebral blood flow (CBF) and its regulatory mechanisms, but the effects of CO2 measurement technique on cerebrovascular parameters are unknown. In order to determine if the two most commonly used approaches, face mask (FM) or nasal cannulae (NC), are interchangeable or not, we tested the hypoth...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Minhas JS,Robinson T,Panerai R

    更新日期:2017-06-22 00:00:00

  • The variability of the photoplethysmographic signal--a potential method for the evaluation of the autonomic nervous system.

    abstract::The heart rate variability is composed of low- and high-frequency fluctuations, which are mediated by the sympathetic and the parasympathetic nervous systems. The baseline and the amplitude of the photoplethysmographic (PPG) signal also show fluctuations in the same frequencies. In the current study, PPG examinations ...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Nitzan M,Babchenko A,Khanokh B,Landau D

    更新日期:1998-02-01 00:00:00

  • Microfluidics for flow cytometric analysis of cells and particles.

    abstract::This review describes recent developments in microfabricated flow cytometers and related microfluidic devices that can detect, analyze, and sort cells or particles. The high-speed analytical capabilities of flow cytometry depend on the cooperative use of microfluidics, optics and electronics. Along with the improvemen...

    journal_title:Physiological measurement

    pub_type: 杂志文章,评审


    authors: Huh D,Gu W,Kamotani Y,Grotberg JB,Takayama S

    更新日期:2005-06-01 00:00:00

  • Fetal beat detection in abdominal ECG recordings: global and time adaptive approaches.

    abstract::We present a method for location of fetal QRS in maternal abdominal ECG recordings. This method's initial, global approach was proposed in the context of the 2013 PhysioNet/Computing in Cardiology Challenge where it was tested on the 447 four channel one-minute recordings.The first step is filtering to eliminate basel...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Rodrigues R

    更新日期:2014-08-01 00:00:00

  • Electroencephalogram classification in motor-imagery brain-computer interface applications based on double-constraint nonnegative matrix factorization.

    abstract:OBJECTIVE:Brain-computer interfaces (BCIs) are aimed at providing a new way of communication between the human brain and external devices. One of the major tasks associated with the BCI system is to improve classification performance of the motor imagery (MI) signal. Electroencephalogram (EEG) signals are widely used f...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Su J,Yang Z,Yan W,Sun W

    更新日期:2020-08-11 00:00:00