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Manual Muscle Testing: A Method of Measuring Extremity Muscle Strength Applied to Critically Ill Patients
Published on: April 12, 2011
Muscle StO2 in critically ill patients
1Department of Intensive Care, Erasme University Hospital, Free University of Brussels, Brussels, Belgium. jcreteur@ulb.ac.be
Current Opinion in Critical Care
|May 10, 2008
Summary
Near-infrared spectroscopy (NIRS) noninvasively measures muscle oxygenation, aiding early detection of hypoperfusion in critically ill patients. Dynamic NIRS variables in sepsis correlate with outcomes, suggesting its utility in guiding management.
Area of Science:
- Critical care medicine
- Hemodynamics
- Biomedical engineering
Background:
- Tissue hypoperfusion is a critical factor in multiple-organ dysfunction and mortality.
- Early detection of inadequate tissue perfusion is essential for timely therapeutic intervention.
- Noninvasive monitoring techniques facilitate earlier initiation of treatment.
Purpose of the Study:
- To review the applicability, usefulness, and limitations of near-infrared spectroscopy (NIRS) for evaluating muscle oxygenation.
- To assess NIRS as a tool for monitoring peripheral oxygenation (StO2) in acutely ill patients.
- To explore the role of NIRS in detecting inadequate tissue perfusion.
Main Methods:
- Review of current knowledge on near-infrared spectroscopy (NIRS) for muscle oxygenation monitoring.
- Analysis of studies evaluating peripheral oxygenation (StO2) using NIRS.
- Investigation of dynamic variables derived from NIRS during occlusion stress.
Main Results:
- Peripheral oxygenation (StO2) measured by NIRS may guide early resuscitation in critically ill patients, particularly those with low cardiac output or trauma.
- NIRS-derived dynamic variables, assessed via occlusion stress, reveal microvascular reactivity and metabolic demand.
- Profound alterations in NIRS-derived dynamic variables are common in severe sepsis and predict poor outcomes.
Conclusions:
- Near-infrared spectroscopy (NIRS) offers a noninvasive method to assess muscle oxygen metabolism and microvascular dysfunction in critically ill patients.
- NIRS may prove valuable in guiding the clinical management of critically ill individuals.
- Further research is needed to establish the full utility of NIRS in specific conditions like sepsis.
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