Andrew H Schmidt1, Michael J Bosse2, William T Obremskey3, Robert V O'Toole4, Eben A Carroll5, Daniel J Stinner6, David J Hak7, Madhav Karunakar2, Roman Hayda8, Katherine P Frey9, Junrui Di9, Vadim Zipunnikov9, Ellen MacKenzie9. 1. Department of Orthopaedics, Hennepin Health System, Minneapolis, Minnesota. 2. Department of Orthopaedic Surgery, Carolinas Medical Center, Charlotte, North Carolina. 3. Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, Tennessee. 4. R Adams Cowley Shock Trauma Center, Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland. 5. Department of Orthopaedic Surgery, Wake Forest University Health Sciences, Winston-Salem, North Carolina. 6. Department of Orthopaedic Surgery, San Antonio Military Medical Center, Fort Sam Houston, Texas. 7. Department of Orthopaedic Surgery, Denver Health Medical Center, Denver, Colorado. 8. Department of Orthopaedic Surgery, Warren Alpert Medical School, Brown University, Providence, Rhode Island. 9. Departments of Health Policy and Management (K.P.F. and E.M.) and Biostatistics (J.D. and V.Z.), Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland.
Abstract
BACKGROUND: We recorded measurements of muscle perfusion using near-infrared spectroscopy (NIRS) and intramuscular pressure (IMP) in a study designed to develop a decision rule for predicting acute compartment syndrome (ACS). The purpose of this study was to report our experience measuring NIRS data in the context of this broader investigation and to explore factors related to variations in data capture. METHODS: One hundred and eighty-five patients with lower-leg injuries had data consisting of continuous NIRS measurement of the O2 saturation in the anterior compartment of the injured limb and the contralateral (control) limb, and continuous IMP recording in the anterior and deep posterior compartments of the injured leg as part of their participation in an institutional review board-approved multicenter trial. All monitoring was done for a prescribed period of time. For both types of data, the percentage of valid data capture was defined as the ratio of the minutes of observed data points within a physiological range to the total minutes of expected data points. Clinically useful NIRS data required simultaneous data from the injured and control limbs to calculate the ratio. Statistical tests were used to compare the 2 methods as well as factors associated with the percent of valid NIRS data capture. RESULTS: For the original cohort, clinically useful NIRS data were available a median of 9.1% of the expected time, while IMP data were captured a median of 87.6% of the expected time (p < 0.001). Excluding 46 patients who had erroneous NIRS data recorded, the median percentage was 31.6% for NIRS compared with 87.4% for IMP data (p < 0.00001). Fractures with an associated hematoma were less likely to have valid data points (odds ratio [OR], 0.53; p = 0.04). Gustilo types-I and II open fractures were more likely than Tscherne grades C0 and C1 closed fractures to have valid data points (OR, 1.97; p = 0.03). CONCLUSIONS: In this study, NIRS data were not collected reliably. In contrast, IMP measurements were collected during >85% of the expected monitoring period. These data raise questions about the utility of current NIRS data capture technology for monitoring oxygenation in patients at risk of ACS.
BACKGROUND: We recorded measurements of muscle perfusion using near-infrared spectroscopy (NIRS) and intramuscular pressure (IMP) in a study designed to develop a decision rule for predicting acute compartment syndrome (ACS). The purpose of this study was to report our experience measuring NIRS data in the context of this broader investigation and to explore factors related to variations in data capture. METHODS: One hundred and eighty-five patients with lower-leg injuries had data consisting of continuous NIRS measurement of the O2 saturation in the anterior compartment of the injured limb and the contralateral (control) limb, and continuous IMP recording in the anterior and deep posterior compartments of the injured leg as part of their participation in an institutional review board-approved multicenter trial. All monitoring was done for a prescribed period of time. For both types of data, the percentage of valid data capture was defined as the ratio of the minutes of observed data points within a physiological range to the total minutes of expected data points. Clinically useful NIRS data required simultaneous data from the injured and control limbs to calculate the ratio. Statistical tests were used to compare the 2 methods as well as factors associated with the percent of valid NIRS data capture. RESULTS: For the original cohort, clinically useful NIRS data were available a median of 9.1% of the expected time, while IMP data were captured a median of 87.6% of the expected time (p < 0.001). Excluding 46 patients who had erroneous NIRS data recorded, the median percentage was 31.6% for NIRS compared with 87.4% for IMP data (p < 0.00001). Fractures with an associated hematoma were less likely to have valid data points (odds ratio [OR], 0.53; p = 0.04). Gustilo types-I and II open fractures were more likely than Tscherne grades C0 and C1 closed fractures to have valid data points (OR, 1.97; p = 0.03). CONCLUSIONS: In this study, NIRS data were not collected reliably. In contrast, IMP measurements were collected during >85% of the expected monitoring period. These data raise questions about the utility of current NIRS data capture technology for monitoring oxygenation in patients at risk of ACS.
Authors: Augustine M Saiz; Alexandria C Wellman; Dustin Stwalley; Philip Wolinsky; Anna N Miller Journal: J Orthop Trauma Date: 2020-05 Impact factor: 2.512
Authors: Abraham Nilsson; Thomas Ibounig; Johan Lyth; Björn Alkner; Ferdinand von Walden; Lotta Fornander; Lasse Rämö; Andrew Schmidt; Jörg Schilcher Journal: BMJ Open Date: 2022-05-02 Impact factor: 3.006