Table 3.

Concentration of TXA (µg mL⁻¹) in plasma samples collected from paediatric patients undergoing scoliosis surgery, determined using the pseudo-molecular [M + H]⁺ ion or the [M + ACN + H]⁺ adduct for quantification.

Plasma Samples a	C[M + ACN + H]+ (This Work)	C[M + H]+ [30]
End of surgery
Patient 1	10.9 ± 0.1 I	11.2 ± 0.1 I
Patient 2	15.7 ± 0.1 II	16.0 ± 0.1 II
Patient 3	17.1 ± 0.5 III	17.1 ± 0.2 III
Patient 4	14.0 ± 0.3 IV	14.2 ± 0.1 IV
Patient 5	9.8 ± 0.1 V	10.0 ± 0.1 V
24 h after surgery
Patient 1	0.213 ± 0.001 VI	0.219 ± 0.002 VI
Patient 2	0.226 ± 0.001 VII	0.229 ± 0.001 VII
Patient 3	0.325 ± 0.002 VIII	0.332 ± 0.002 VIII
Patient 4	0.214 ±0.004 IX	0.226 ± 0.006 IX
Patient 5	0.269 ± 0.004 X	0.275 ± 0.001 X

^a Each value corresponds to the mean ± standard deviation (n = 2). Prior to analysis by UHPLC-MS/MS, sample extracts collected at the end of surgery were diluted 20 times in mobile phase; ^I–X Comparison between the mean TXA concentration values determined in clinical plasma samples. The same superscript number indicates that no statistically significant difference was found for the results obtained by the two quantification methods (p < 0.05).