Gastric Emptying Velocity After Labor Analgesia Assessed by Sonography: A Prospective Controlled Observational Study

Figures & data

Figure 1 The CONSORT flow diagram.

Abbreviations: ITT, Intention-to-treat; PP: Per-protocol.

Table 1 Results of Intention-to-Treat Analysis

Items	Study Group, n=90	Observation Group, n=30	p value
Demographic
Age (years)	26.71 ± 3.13	27.33 ± 2.82	0.336
Height (cm)	165.81 ± 6.84	166.37 ± 7.86	0.711
Weight (kg)	72.93 ± 9.20	74.57 ± 9.57	0.406
BMI	26.61 ± 3.65	27.07 ± 4.14	0.564
Gestational weeks	38.31 ± 1.16	38.13 ± 1.07	0.460
Fundal height (cm)	34.26 ± 1.51	34.37 ± 1.43	0.724
Abdominal circumference (cm)	92.87 ± 3.05	93.00 ± 3.46	0.842
AFI	11.80 ± 3.84	11.30 ± 3.55	0.531
Duration of labor (min)
First stage of labor	671.43 ± 53.01	685.77 ± 48.15	0.192
Second stage of labor	95.97 ± 22.85	94.17 ± 23.69	0.712
Third stage of labor	14.49 ± 6.31	12.83 ± 5.81	0.207
Total stage of labor	781.89 ± 57.59	792.77 ± 49.25	0.356
VAS at different times
Tbaseline	5.52 ± 1.14	5.53 ± 1.20	0.964
T1	3.47 ± 1.13	3.50 ± 1.11	0.889
T2	3.13 ± 0.91	3.27 ± 1.05	0.506
Fetal weight (g)	3241.61 ± 593.08	3156.40 ± 597.48	0.498
Postpartum Apgar score
Apgar-post 1 min	8.61 ± 0.94	8.67 ± 0.88	0.777
Apgar-post 5 min	9.79 ± 0.51	10.00 ± 0.00	0.025*
CSA at 3 time-points(mm^2)
CSAbaseline	624.19 ± 92.70	620.10 ± 100.73	0.838
CSApost 1 hr	334.64 ± 46.32	331.30 ± 51.19	0.739
CSApost 2 hrs	217.26 ± 29.90	214.70 ± 28.73	0.683
Gastric emptying at first 2 hrs (mm^2)
∆S1=(CSAbaseline-CSApost 1hr)	289.54 ± 105.62	288.80 ± 123.58	0.975
∆S2=(CSApost 1hr-CSApost 2hrs)	117.39 ± 51.17	118.93 ± 56.74	0.889
Total dose of fentanyl for analgesia, (μg)	104.25 ± 7.68	201.27 ± 82.04	<0.001*
Occurrence of nausea and vomiting, n(%)	4 (4.44)	2 (6.67)	0.469
Pulmonary complications after the delivery, n(%)	0 (0.00)	0 (0.00)	>0.999
Dilatation of cervix during epidural catheter insertion, Median (IQR)	2.5 (1.5, 3.125)	2 (1.5, 4.125)	0.424
Cumulative doses of ropivacaine, (mg)	144.91 ± 79.35	74.70 ± 73.67	<0.001*
Oxytocin infusion, n (%)			0.367
Yes	87 (96.67)	28 (93.33)
No	3 (3.33)	2 (6.67)

Notes: T_baseline: After taken the experimental diet but before the implementation of labor analgesia management; T₁: at the end of the first stage of labor; T₂: at 30 minutes after the delivery of the placenta. *Compared with the Study group, p<0.05.

Abbreviations: BMI, Body mass index; VAS, visual analogue scale; CSA, cross-sectional area of the antrum; AFI, Amniotic fluid index.

Figure 2 The changes of CSA and VAS. (A and B) show the results of ITT analysis, (C and D) show the results of PP analysis.

Notes: *Compared with the baseline, p<0.001. ^#Compared with the 1 hr or T₁,p<0.001. ^$Compared with the observation group, p<0.001.

Abbreviations: ITT, Intention-to-treat; PP, Per-protocol; CSA, cross-sectional area of the antrum; VAS, visual analogue scale.

Table 2 Results of per-Protocol Analysis

Items	Study Group, n=73	Observation Group, n=14	p value
Demographic
Age (years)	26.60 ± 3.13	27.36 ± 3.18	0.412
Height (cm)	165.74 ± 6.60	164.43 ± 7.84	0.511
Weight (kg)	72.19 ± 8.80	75.00 ± 10.60	0.293
BMI	26.36 ± 3.55	27.77 ± 3.86	0.184
Gestational weeks	38.38 ± 1.17	38.29 ± 1.27	0.779
Fundal height (cm)	34.10 ± 1.52	34.57 ± 1.40	0.281
Abdominal circumference (cm)	92.68 ± 3.13	93.57 ± 3.25	0.337
AFI	11.75 ± 3.82	11.57 ± 3.82	0.871
Duration of labor (min)
First stage of labor	669.29 ± 55.16	676.00 ± 49.49	0.673
Second stage of labor	96.84 ± 22.66	89.36 ± 21.33	0.257
Third stage of labor	14.36 ± 6.22	13.71 ± 6.11	0.724
Total stage of labor	780.48 ± 59.57	779.07 ± 48.02	0.934
VAS at different times
Tbaseline	5.52 ± 1.14	5.07 ± 1.21	0.186
T1	3.48 ± 1.11	3.64 ± 1.15	0.616
T2	3.05 ± 0.85	3.71 ± 1.14	0.014*
Fetal weight (g)	3211.53 ± 577.06	2955.50 ± 518.52	0.126
Postpartum Apgar score
Apgar-post 1 min	8.60 ± 0.95	8.57 ± 0.94	0.910
Apgar-post 5 min	9.90 ± 0.63	10.0 ± 0.00	0.571
CSA at 3 time-points(mm^2)
CSAbaseline	632.08 ± 95.04	596.36 ± 94.62	0.201
CSApost 1 hr	332.03 ± 45.33	336.86 ± 56.83	0.727
CSApost 2 hrs	219.42 ± 29.79	216.79 ± 23.78	0.755
Gastric emptying at first 2 hrs (mm^2)
∆S1=(CSAbaseline-CSApost 1hr)	300.05 ± 103.74	259.50 ± 125.25	0.199
∆S2=(CSApost 1hr-CSApost 2hrs)	115.75 ± 43.51	124.36 ± 58.98	0.525
Total dose of fentanyl for analgesia, (μg)	104.06 ± 7.94	139.43 ± 69.13	0.078
Occurrence of nausea and vomiting, n(%)	2 (2.74)	1 (7.14)	0.413
Pulmonary complications after the delivery, n(%)	0 (0.00)	0 (0.00)	>0.999
Dilatation of cervix during epidural catheter insertion, Median (IQR)	2 (1, 3)	4.25 (3.875, 4.625)	<0.001*
Oxytocin infusion, n (%)			0.839
Yes	72 (98.63)	14 (100.00)
No	1 (1.37)	0 (0.00)

Notes: T_baseline: After taken the experimental diet but before the implementation of labor analgesia management; T₁: at the end of the first stage of labor; T₂: at 30 minutes after the delivery of the placenta. *Compared with the Study group, p<0.05.

Abbreviations: BMI, Body mass index; VAS, visual analogue scale; CSA, cross-sectional area of the antrum; AFI, Amniotic fluid index.