ArticleCritical care (London, England)2019
The effects of passive leg raising may be detected by the plethysmographic oxygen saturation signal in critically ill patients.
Article in Critical care (London, England), 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 47 papers, 1 of them a synthesis that pooled it.
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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.
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Who cites it
47 citing papers in PubMed, 1 synthesis or guideline pooled it.
- ESICM guidelines on circulatory shock and hemodynamic monitoring 2025.Intensive care medicine · 2025Guideline
- To identify normovolemia in humans: The stroke volume response to passive leg raising vs. head-down tilt.Physiological reports · 2022Trial
- Effects of nitroglycerin versus labetalol on peripheral perfusion during deliberate hypotension for sinus endoscopic surgery: a randomized, controlled, double-blinded trial.BMC anesthesiology · 2020Trial
- Beyond macrocirculatory targets: a multimodal framework for microcirculatory and organ perfusion monitoring in sepsis.Critical care (London, England) · 2026Review
- Significance of Peripheral Perfusion Changes During Remote Ischemic Conditioning in Critically Ill Patients.Journal of clinical medicine · 2026Article
- The reliability of the plethysmographic perfusion index for detecting fluid responsiveness in critically ill patients.Journal of intensive medicine · 2026Article
- Perfusion index and fluid responsiveness: Are we asking the right question?Journal of intensive medicine · 2026Article
- Ultrafiltration in the critically ill patient: a framework for personalized care.Critical care (London, England) · 2026Review
- Variation of perfusion index to evaluate fluid responsiveness during the preload challenge tests: a systematic review and meta-analysis.Annals of intensive care · 2026Article
- Non-Invasive Hemodynamic Monitoring in Critically Ill Patients: A Guide for Emergency Physicians.Journal of clinical medicine · 2025Review
- Detection of fluid responsiveness by changes of perfusion index and pleth-variability index during passive leg raising in spontaneously breathing post-surgical patients: a prospective interventional study.Journal of clinical monitoring and computing · 2025Article
- Assessing fluid responsiveness by using functional hemodynamic tests in critically ill patients: a narrative review and a profile-based clinical guide.Journal of clinical monitoring and computing · 2025Review
- The Accuracy of the Passive Leg Raising Test Using the Perfusion Index to Identify Preload Responsiveness-A Single Center Study in a Resource-Limited Setting.Diagnostics (Basel, Switzerland) · 2025Article
- Early peripheral perfusion monitoring in septic shock.European journal of medical research · 2024Review
- Testing preload responsiveness by the tidal volume challenge assessed by the photoplethysmographic perfusion index.Critical care (London, England) · 2024Article
- Peripheral perfusion index of pulse oximetry in adult patients: a narrative review.European journal of medical research · 2024Review
- Prediction of preload dependency using phenylephrine-induced peripheral perfusion index during general anaesthesia: a prospective observational study.BMC anesthesiology · 2024Observational
- Peripheral perfusion response to semiorthostatic stress: a simple method for assessing autonomic dysfunction in sepsis?Critical care science · 2024Article
- "The peripheral perfusion index discriminates haemodynamic responses to induction of general anaesthesia".Journal of clinical monitoring and computing · 2023Article
- Supine transfer test-induced changes in cardiac index predict fluid responsiveness in patients without intra-abdominal hypertension.BMC anesthesiology · 2023Article
Corrections and comments
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Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundA passive leg raising (PLR) test is positive if the cardiac index (CI) increased by > 10%, but it requires a direct measurement of CI. On the oxygen saturation plethysmographic signal, the perfusion index (PI) is the ratio between the pulsatile and the non-pulsatile portions. We hypothesised that the changes in PI could predict a positive PLR test and thus preload responsiveness in a totally non-invasive way.
methodsIn patients with acute circulatory failure, we measured PI (Radical-7) and CI (PiCCO2) before and during a PLR test and, if decided, before and after volume expansion (500-mL saline).
resultsThree patients were excluded because the plethysmography signal was absent and 3 other ones because it was unstable. Eventually, 72 patients were analysed. In 34 patients with a positive PLR test (increase in CI ≥ 10%), CI and PI increased during PLR by 21 ± 10% and 54 ± 53%, respectively. In the 38 patients with a negative PLR test, PI did not significantly change during PLR. In 26 patients in whom volume expansion was performed, CI and PI increased by 28 ± 14% and 53 ± 63%, respectively. The correlation between the PI and CI changes for all interventions was significant (r = 0.64, p < 0.001). During the PLR test, if PI increased by > 9%, a positive response of CI (≥ 10%) was diagnosed with a sensitivity of 91 (76-98%) and a specificity of 79 (63-90%) (area under the receiver operating characteristics curve 0.89 (0.80-0.95), p < 0.0001).
conclusionAn increase in PI during PLR by 9% accurately detects a positive response of the PLR test.
trial registrationID RCB 2016-A00959-42. Registered 27 June 2016.
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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.