Objective:To investigate the effect of the 3t sensorial saturation in the application of relieving pain and comfort due to femoral vein blood sampling in preterm infants, so as to provide the reference for the selection of clinical nursing plans.Methods:This was a quasi experimental study. A total of 110 preterm infants admitted to the neonatal unit of Shanxi Children′s Hospital from August 2021 to March 2022 were selected and divided into the control group and intervention group with 52 cases respectively by the random number table method. The control group implemented conventional care, and the intervention group implemented the 3t sensorial saturation method including taste, touch and talk on the basis of the control group. The pain and comfort of two groups were evaluated by the Premature Infant Pain Profile (PIPP) and COMFORTneo Scale at 3 min before, during, and 3 min after blood, and the heart rate and SpO 2 of the two groups were compared. Results:Finally, 52 premature infants were included in both groups. The PIPP score, the total score of the COMFORTneo Scale, the heart rate and SpO 2 were 2.00 (1.00, 3.00), 6.50 (6.00, 7.75), 4.00 (3.00, 5.00), 7.00 (6.00, 8.00), 17.00 (15.00, 19.00), 9.50 (9.00, 10.00) points, (137.29 ± 8.58), (148.31 ± 8.89), (143.06 ± 7.61) times/min, 0.980 (0.970, 0.990), 0.960 (0.950, 0.970), 0.980 (0.970, 0.990) in the intervention group, 2.00 (1.25, 3.00), 12.00 (11.00, 13.00), 7.00 (6.00, 8.00), 7.00 (6.00, 9.00), 25.00 (23.00, 27.00), 20.00 (19.00, 22.00) points, (141.54 ± 10.57), (179.71 ± 14.62), (162.00 ± 14.32) times/min, 0.980 (0.960, 0.990), 0.940 (0.920, 0.958), 0.960 (0.940, 0.978). The results of generalized estimating equation analysis showed that the PIPP score, total COMFORTneo Scale score and SpO 2 via different time points, subgroups, and subgroups with time points were statistically significant (Wald χ2 values were 16.72-2 489.71, all P<0.05). The results of two-factor repeated measures ANOVA showed that the interaction effects of heart rate via different time points, subgroups, and subgroups with time points were statistically significant ( F=253.08, 105.02, 77.17, all P<0.05). Conclusions:The 3t sensorial saturation method can effectively reduce pain during femoral vein blood sampling in preterm infants, can improve the comfort level of preterm infants, is conducive to the stabilization of vital signs in preterm infants, and is suitable for promotion and application in clinical care.