Administration of hydrogen sulfide via extracorporeal membrane lung ventilation in sheep with partial cardiopulmonary bypass perfusion: a proof of concept study on metabolic and vasomotor effects

Table 1 Hemodynamics and blood gas data^a

Parameter	0 ppm	100 ppm	0 ppm	200 ppm	0 ppm	300 ppm
Hemodynamics, means ± SD
HR, beats/min	139 ± 24	148 ± 29	154 ± 5	172 ± 28	165 ± 28	150 ± 31
MAP, mmHg	110 ± 13	117 ± 14	115 ± 11	128 ± 16	121 ± 15	66 ± 11^b
MPAP, mmHg	15 ± 3	19 ± 3*	19 ± 3	22 ± 4	20 ± 4.0	31 ± 7^b
CO, l/min	4.6 ± 1.4	4.9 ± 2.0	5.1 ± 1.5	5.2 ± 1.7	5.8 ± 2.3	5.5 ± 1.2
CVP, mmHg	9 ± 2	9 ± 1.0	10 ± 1	11 ± 2	11 ± 1	11 ± 2
PCWP, mmHg	7 ± 2	7 ± 2	7 ± 8	8 ± 2	9 ± 2	10 ± 2
SVR, dyn·s/cm⁵	1,843 ± 435	1,948 ± 525	1,734 ± 412	2,009 ± 703^b	1,561 ± 553	870 ± 138^b
PVR, dyn·s/cm⁵	145 ± 32	191 ± 52^b	203 ± 36	255 ± 70^b	138 ± 27	279 ± 138^b
Hb, pH, blood gas tensions, and temperature, means ± SD
Hb_a, g/dl	8.6 ± 1.3	9.0 ± 1.3	9.1 ± 1.0	11.1 ± 1.4^b	9.5 ± 0.6	9.6 ± 1.2
pH_a	7.401 ± 0.072	7.369 ± 0.079	7.375 ± 0.051	7.346 ± 0.063	7.312 ± 0.089	7.217 ± 0.064^b
P_aO₂, mmHg	161 ± 28	150 ± 40	150 ± 37	107 ± 39	114 ± 36	83 ± 23^b
P_aCO₂, mmHg	38 ± 13	38 ± 11	35 ± 7	34 ± 5	36 ± 7.0	38 ± 4
pH_v	7.383 ± 0.074	7.360 ± 0.080	7.360 ± 0.056	7.346 ± 0.066	7.302 ± 0.087	7.210 ± 0.068^b
P_vO₂, mmHg	50 ± 5	52 ± 6^b	52 ± 4	54 ± 4	56 ± 4	52 ± 7
P_vCO₂, mmHg	41 ± 14	41 ± 11	38 ± 8	35 ± 5	38 ± 6	40 ± 4
Temperature,°C	37.5 ± 0.6	37.5 ± 0.4	37.5 ± 0.3	37.3 ± 0.4	37.3 ± 0.4	37.1 ± 0.5

^aHemodynamics and blood gas data in five sheep challenged with alternate exposure to H₂S by ventilation of an extracorporeal membrane lung with 0 or 100 ppm H₂S, 200 ppm H₂S or 300 ppm H₂S in air for 1-hour intervals each. ppm, parts per million; HR, heart rate; MAP, mean arterial pressure; MPAP, mean pulmonary artery pressure; CO, cardiac output; CVP, central venous pressure; PCWP, pulmonary capillary wedge pressure; SVR, systemic vascular resistance; PVR, pulmonary vascular resistance; Hb_a, arterial hemoglobin concentration; pH_a, arterial pH; P_aO₂, arterial oxygen tension; P_aCO₂, arterial carbon dioxide tension; pH_v, mixed venous pH; P_vO₂, mixed venous oxygen tension; P_vCO₂, mixed venous carbon dioxide tension. All values are means ± SD and reflect the last 10 minutes of each 1-hour period. n = 5. Values during H₂S exposure were compared using Student's t-test or the Wilcoxon signed-rank test with the preceding 0 ppm baseline period, that is, first vs. second hour, third vs. fourth hour and fifth vs. sixth hour; ^bP ≤ 0.05.

ISSN: 1364-8535