Evidence map›Paper›PMID 30642260›Full record

ArticleBMC medical research methodology2019

The triple variable index combines information generated over time from common monitoring variables to identify patients expressing distinct patterns of intraoperative physiology.

Michael P Schnetz, Harry S Hochheiser, David J Danks, Douglas P Landsittel, Keith M Vogt, James W Ibinson, Steven L Whitehurst, Sean P McDermott, Melissa Giraldo Duque, Ata M Kaynar

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in BMC medical research methodology, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

Michael P SchnetzDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA. mps93@pitt.edu.ORCID 0000-0003-4447-1640
Harry S HochheiserDepartment of Biomedical Informatics, University of Pittsburgh, 5607 Baum Boulevard, Pittsburgh, PA, 15206, USA.
David J DanksDepartments of Philosophy and Psychology, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA, 15213, USA.
Douglas P LandsittelDepartment of Biomedical Informatics, University of Pittsburgh, 5607 Baum Boulevard, Pittsburgh, PA, 15206, USA.
Keith M VogtDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.
James W IbinsonDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.
Steven L WhitehurstDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.
Sean P McDermottDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.
Melissa Giraldo DuqueDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.
Ata M KaynarDepartment of Anesthesiology, University of Pittsburgh, 3550 Terrace Street, Pittsburgh, PA, 15261, USA.

Funding

Research Training in Anesthesiology and Pain MedicineT32GM075770 · NIGMS · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · PI YAN XU · 2007 to 2026
$4.8M
Combined viral and bacterial infection and zinc homeostasis in distal lungR01HL126711 · NHLBI · UNIVERSITY OF PITTSBURGH AT PITTSBURGH · PI KAYNAR, A. MURAT · 2015 to 2019
$2.0M
NHLBI NIH HHS R01 HL126711NIGMS NIH HHS T32 GM075770
6 · The paper itself

Abstract

backgroundMean arterial pressure (MAP), bispectral index (BIS), and minimum alveolar concentration (MAC) represent valuable, yet dynamic intraoperative monitoring variables. They provide information related to poor outcomes when considered together, however their collective behavior across time has not been characterized.

methodsWe have developed the Triple Variable Index (TVI), a composite variable representing the sum of z-scores from MAP, BIS, and MAC values that occur together during surgery. We generated a TVI expression profile, defined as the sequential TVI values expressed across time, for each surgery where concurrent MAP, BIS, and MAC monitoring occurred in an adult patient (≥18 years) at the University of Pittsburgh Medical Center between January and July 2014 (n = 5296). Patterns of TVI expression were identified using k-means clustering and compared across numerous patient, procedure, and outcome characteristics. TVI and the triple low state were compared as prediction models for 30-day postoperative mortality.

resultsThe median frequency MAP, BIS, and MAC were recorded was one measurement every 3, 5, and 5 min. Three expression patterns were identified: elevated, mixed, and depressed. The elevated pattern displayed the highest average MAP, BIS, and MAC values (86.5 mmHg, 45.3, and 0.98, respectively), while the depressed pattern displayed the lowest values (76.6 mmHg, 38.0, 0.66). Patterns (elevated, mixed, depressed) were distinct across the following characteristics: average patient age (52, 53, 54 years), American Society of Anesthesiologists Physical Status 4 (6.7, 16.1, 27.3%) and 5 (0.1, 0.6, 1.6%) categories, cardiac (2.2, 6.5, 16.1%) and emergent (5.8, 10.5, 12.8%) surgery, cardiopulmonary bypass use (0.3, 2.6, 9.8%), intraoperative medication administration including etomidate (3.0, 7.3, 12.6%), hydromorphone (47.6, 26.3, 25.2%), ketamine (11.2, 4.6, 3.0%), dexmedetomidine (18.4, 16.6, 13.6%), phenylephrine (74.0, 74.8, 83.0), epinephrine (2.0, 6.0, 18.0%), norepinephrine (2.4, 7.5, 21.2%), vasopressin (3.4, 7.6, 21.0%), succinylcholine (74.0, 69.0, 61.9%), intraoperative hypotension (28.8, 33.0, 52.3%) and the triple low state (9.4, 30.3, 80.0%) exposure, and 30-day postoperative mortality (0.8, 2.7, 5.6%). TVI was a better predictor of patients that died or survived in the 30 days following surgery compared to cumulative triple low state exposure (AUC 0.68 versus 0.62, p < 0.05).

conclusionsSurgeries that share similar patterns of TVI expression display distinct patient, procedure, and outcome characteristics.

Indexed as

Consciousness MonitorsThoracic Surgical ProceduresAdultArterial PressureCardiopulmonary BypassHumansMachine LearningMiddle AgedMonitoring, IntraoperativePerioperative MedicinePulmonary AlveoliBispectral indexIntraoperative monitoringK-means clusteringMean arterial pressureMinimum alveolar concentrationPerioperative medicinePostoperative deathTriple low stateTriple variable indexUnsupervised machine learning

Identifiers

PMID30642260
PMCPMC6332613

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.