The Matching of Sinus Arrhythmia to Respiration: Are Trauma Patients without Serious Injury Comparable to Healthy Laboratory Subjects?

We sought to better understand the physiology underlying the metrics of heart rate variability HRV in trauma patients without serious injury, compared to healthy laboratory controls. In trauma patients without serious injury 110 subjects, 470 2-min data segments, we studied the correlation between sinus arrhythmia SA rate, heart rate HR, and respiratory rate RR. Most segments with 2.4 HRRR 4.8 exhibited SA-RR matching, whereas rate matching was absent in 81 of the segments with HRRR 2.4 and in 86 of the segments with HRRR 4.8. The findings were comparable, in some cases remarkably so, to previous reports from healthy laboratory subjects. The presence or absence of SA-RR matching, when SA is largely controlled by respiration, can be anticipated in this trauma population. This work provides a valuable step towards the definition of patterns of HRV found in trauma patients with and without lifethreatening injury.