Predictive value for weakness and 1-year mortality of screening electrophysiology tests in the ICU
- PMID: 26266842
- DOI: 10.1007/s00134-015-3979-7
Predictive value for weakness and 1-year mortality of screening electrophysiology tests in the ICU
Abstract
Purpose: Muscle weakness in long-stay ICU patients contributes to 1-year mortality. Whether electrophysiological screening is an alternative diagnostic tool in unconscious/uncooperative patients remains unknown. We aimed to determine the diagnostic properties of abnormal compound muscle action potential (CMAP), sensory nerve action potential (SNAP), and spontaneous electrical activity (SEA) for Medical Research Council (MRC)-defined weakness and their predictive value for 1-year mortality.
Methods: Data were prospectively collected during the EPaNIC trial (ClinicalTrials.gov: NCT00512122). First, sensitivity, specificity, positive (PPV) and negative predictive values (NPV) of abnormal CMAP, SNAP, and SEA for weakness were determined. Subsequently, association between 1-year mortality and abnormal findings on electrophysiological screening was assessed by univariate and multivariate analyses correcting for weakness and other risk factors and the prediction model involved only a development phase.
Results: A total of 730 patients were electrophysiologically screened of whom 432 were tested for weakness. On day 8, normal CMAP excluded weakness with a high NPV (80.5 %). By day 15, abnormal SNAP and the presence of SEA had a high PPV (91.7 and 80.0 %, respectively). Only a reduced CMAP on day 8 was associated with higher 1-year mortality [35.6 vs 15.2 % (p < 0.001)]. This association remained significant after correction for weakness and other risk factors [OR 2.463 (95 % CI 1.113-5.452), p = 0.026]. Also among conscious/cooperative patients without weakness, reduced CMAP was independently associated with a higher likelihood of death occurring during 1 year [HR 2.818 (95 % CI 1.074-7.391), p = 0.035].
Conclusions: The diagnostic properties of electrophysiological screening vary over time. Abnormal CMAP documented early during critical illness carries information about longer-term outcome, which should be further investigated mechanistically.
Keywords: Electrophysiology; Intensive care; Mortality; Muscle weakness.
Comment in
-
Finally, a time and place for electrophysiological testing in critically ill patients?Intensive Care Med. 2015 Dec;41(12):2221-3. doi: 10.1007/s00134-015-4083-8. Epub 2015 Sep 30. Intensive Care Med. 2015. PMID: 26424681 No abstract available.
References
Publication types
MeSH terms
Associated data
LinkOut - more resources
Full Text Sources
Medical