Methylene blue compared to norepinephrine in the management of vasoplegic syndrome in pediatric patients after cardiopulmonary bypass: a randomized controlled study

Peer review under responsibility of Egyptian Society of Anesthesiologists.

Figures & data

able 1 Patients’ Characteristics.

Variable	MB group (n = 20)	N group (n = 20)	p-value
Age (months)	30.85 ± 10.12	31.4 ± 7.7	0.85
Weight (kg)	12.14 ± 1.23	12.3 ± 1.37	0.78
Height (cm)	90.65 ± 6.7	91.1 ± 5.9	0.46
BSA (m^2)	0.55 ± 0.12	0.56 ± 0.31	0.936
Sex (male/female)	13/7	11/9	0.747
Diagnosis
– AV	7	8	0.892
– VSD	8	7
– VSD + ASD	1	2
– F4	4	3
Down	5	7	0.9
Preoperative ACEI	15	15	1
Preoperative diuretic	16	13	0.479
Preoperative beta- blocker	6	7	0.736
Doses of cardioplegia
– 2 doses	16	15	0.705
– 3 doses	4	5
Preoperative hematocrit (%)	43.6 ± 5	41.2 ± 4.7	0.135
Diameter of aortic valve annulus (mm)	9.05 ± 0.77	9.045 ± 0.73	0.983
Aortic valve area (cm^2)	0.76 ± 0.06	0.765 ± 0.078	0.673
Aortic valve area index (cm^2/m^2)	1.27 ± 0.103	1.24 ± 0.85	0.329
Preoperative EF (%)	0.577 ± 0.11	0.587 ± 0.1	0.74

Values are presented as mean ± SD or number. BSA: body surface area, AV: common atrio-ventricular canal, VSD: ventricular septal defect, ASD: atrial septal defect, F4: Fallot’s tetralogy, ACEI: angiotensin converting enzyme inhibitor.

All p-values are >0.05, insignificant difference.

able 2 Cardiopulmonary bypass details.

Variable	MB group (n = 20)	N group (n = 20)	p-value
Temperature on CPB (°C)	27.15 ± 1.05	27 ± 1.35	0.691
Volume of cardioplegic solution (ml)	329.7 ± 109	351.5 ± 90.97	0.230
Duration of CPB (min)	95.3 ± 5.4	93.05 ± 4.96	0.177
Duration of AoX (min)	69.3 ± 8.3	67.55 ± 8.3	0.51
SaO2 (%)	97.75 ± 0.9	98.1 ± 0.89	0.298
Dose of nitroglycerin (μg/kg/min)	1.97 ± 0.37	2.06 ± 0.4	0.448

Values are presented as mean ± SD. CPB: cardiopulmonary bypass, AoX: aortic cross clamping.

All p-values are >0.05, insignificant difference.

able 3 Comparison between Time 1 and Time 2 values of the studied drugs in heart rate, MAP and CVP.

	MB group (n = 20)		N group (n = 20)		p-value (Time 1 MB versus N)	p-value (Time 2 MB versus N)
	Time 1	Time 2	Time 1	Time 2
Norepinephrine (μg/kg/min)	0.5 ± 0	0.11 ± 0.019	0.5 ± 0	1.42 ± 0.5	1	<0.001^⁎⁎
	<0.001^⁎		<0.001^⁎
Heart rate (beat/m)	165.6 ± 5.8	151.75 ± 4.57	165.8 ± 6.6	161 ± 3.7	0.919	<0.001^⁎⁎
	<0.001^⁎		0.82
MAP (mmHg)	39.1 ± 4.5	56 ± 4.6	38.5 ± 5	43.5 ± 10.6	0.692	<0.001^⁎⁎
	<0.001^⁎		0.085
CVP (mmHg)	4.95 ± 0.69	7.2 ± 0.7	4.9 ± 2.83	5.9 ± 2.3	0.939	<0.001^⁎⁎
	<0.001^⁎		0.335

MAP: mean arterial blood pressure, CVP: central venous pressure.

Values are presented as mean ± SD. p-value <0.05 significant difference.

#x204E; Statistically significant between Time1 and Time 2 values in each group.

#x204E;⁎ Statistically significant between the two groups.

able 4 Comparison between Time 1 and Time 2 values of the studied drugs in CO, CI, MPAP, SVR and SVRI.

	MB Group (n = 20)		N Group (n = 20)		p-value (Time 1 MB versus N)	p-value (Time 2 MB versus N)
	Time 1	Time 2	Time 1	Time 2
CO (l/min)	3.83 ± 0.43	3.3 ± 0.22	3.72 ± 0.51	3.51 ± 0.18	0.465	0.002^⁎⁎
	<0.001^⁎		0.09
CI (l/min/m^2)	6.96 ± 0.46	6.0 ± 0.3	6.64 ± 0.82	6.27 ± 0.38	0.136	0.017^⁎⁎
	<0.001^⁎		0.075
MPAP (mmHg)	22.25 ± 3.1	23.95 ± 2.3	22.55 ± 3.71	23.85 ± 2.37	0.783	0.890
	0.056		0.195
SVR (dyn s/cm^5)	675.37 ± 40	1219.39 ± 121.6	696.66 ± 78.65	721.57 ± 97.3	0.287	<0.001^⁎⁎
	<0.001^⁎		0.379
SVRI (dyn s/cm^5/m^2)	1227.94 ± 155.29	2217.07 ± 143.1	1242.85 ± 170.2	1287.44 ± 230.87	0.774	<0.001^⁎⁎
	<0.001^⁎		0.491

CO: cardiac output, CI: cardiac index, MPAP: mean pulmonary artery pressure, SVR: systemic vascular resistance, SVRI: systemic vascular resistance index.

Values are presented as mean ± SD. p-value <0.05 significant difference.

#x204E; Statistically significant between Time 1 and Time 2 values in each group.

#x204E;⁎ Statistically significant between the two groups.

igure 1 Study flowchart.