Using pulse oximetry waveforms to detect coarctation of the aorta

Table 4 Preoperative vs postoperative waveform characteristics for differences between upper and lower extremities

Waveform features	Preoperative	Postoperative	p value
Waveform features	Median [Q1, Q3]		p value
∆ARR	− 1.2 [− 4.5, 0.19]	− 0.16 [− 3.3, 2.6]	0.13
∆ARF	− 2 [− 2.6, − 0.085]	− 0.63 [− 1.7, 0.34]	0.2
∆MRR	− 1.2 [− 4.6, 0.24]	− 0.14 [− 3.3, 3]	0.16
∆MRF**	− 2.4 [− 3.8, 1.3]	− 0.3 [− 2.9, 0.71]	0.028

Reported as the median, 1st and 3rd quartiles of PPG features evaluated for COA before and after surgical repair. Subscripts indicate upper (u) vs lower (l) extremity acquisition site. The ∆ indicates the difference between the upper and lower extremity for that feature. The two-sided Wilcoxon rank sum test was used to test for significance. Features with statistical significance between the 2 groups are marked as **p value < 0.05
ARR average rate of rise, ARF average rate of fall, MRR maximum rate of rise, MRF maximum rate of fall, COA coarctation of the aorta, Q1 1st quartile, Q3 3rd quartile

ISSN: 1475-925X