Heparin does not seem to improve the function of pulmonary grafts for lung transplantation

Figures & data

Figure 1. EVLP was performed using the Medtronics Ex Vivo Lung Evaluation Set extracorporeal perfusion circuit by Medtronics (Medtronic AB, Kerkrade, the Netherlands; Ex Vivo Lung Evaluation Set).

Table I. The EVLP data expressed as median and range HBD receiving heparin and those without heparin for inspired oxygen fractions of 1.0, 0.5, and 0.21.

	HBDS with heparin		HBDS without heparin
	Median	Range	Median	Range	p value
FiO2 1.0
PAP (mmHg)	20	(14–20)	20	(16–20)	0.99
Pulmonary artery flow (l/min)	3.0	(2.6–4.0)	3.0	(2.1–4.0)	0.71
PaO2 (kPa)	69.2	(46. 1–77. 0)	61.6	(47.9–71.4)	0.44
PaCO2 (kPa)	3.7	(2.6–3.8)	3.1	(2.9–3.9)	0.99
PvO2 (kPa)	6.8	(6.2–7.0)	8.7	(5.3–16. 1)	0.09
PvCO2 (kPa)	3.9	(3.8–4.0)	3.5	(2.8–3.8)	0.03
PVR ((dynes × s)/cm^5)	543	(280–615)	533	(320–762)	0.99
FiO2 0.5
PAP (mmHg)	20	(15–20)	20	(16–20)	0.99
Pulmonary artery flow (l/min)	3.0	(2.6–4.0)	3.0	(2.1–4.0)	0.71
PaO2 (kPa)	40.5	(28.1–44. 0)	32.8	(25.2–41.7)	0.22
PaCO2 (kPa)	3.6	(2.4–3.8)	3.3	(2.9–5.1)	0.99
PvO2 (kPa)	6.6	(6.2–7.0)	8.1	(6.2–14. 2)	0.06
PvCO2 (kPa)	3.8	(2.9–4.1)	3.5	(3.1–3.8)	0.17
PVR ((dynes × s)/cm^5)	543	(300–615)	533	(320–762)	0.63
FiO2 0.21
PAP (mmHg)	20	(14–20)	20	(16–20)	0.99
Pulmonary artery flow (l/min)	3.0	(2.6–4.0)	3.0	(2.1–4.0)	0.71
PaO2 (kPa)	10.5	(9.2–12.1)	12.0	(9.9–15.2)	0.16
PaCO2 (kPa)	3.4	(2.7–3.7)	3.4	(3.0–4.9)	0.75
PvO2 (kPa)	6.5	(3.8–6.8)	3.8	(3.5–4.4)	0.06
PvCO2 (kPa)	3.5	(3.1–3.9)	3.4	(3.2–4.5)	0.75
PVR ((dynes × s)/cm^5)	543	(280–615)	533	(320–762)	0.99

Statistical analysis was performed using Wilcoxon's test to compare the two groups of HBDs with and without heparin with respect to lung function.

Significance was defined as p < 0.05 (*), p < 0.01 (**), p < 0.001 (***), and p > 0.05 (not significant, n.s.).

FiO₂, Inspired oxygen fraction; PAP, pulmonary arterial pressure; PaO₂, arterial oxygen partial pressure; PaCO₂, arterial carbon dioxide partial pressure; PvO₂, venous oxygen partial pressure; PvCO₂, venous carbon dioxide partial pressure; PVR, pulmonary vascular resistance.

Figure 2. Mean lung weight (± SEM) after harvesting, before EVLP, and after completion of EVLP for pulmonary grafts from the two groups of pigs: one not treated with heparin, and the other treated with heparin. Statistical analysis was performed using Wilcoxon's test. Significance was defined as p < 0.05 (*), p < 0.01 (**), p < 0.001 (***), and p > 0.05 (not significant, n.s.).

Figure 3. After lung evaluation the pulmonary arterial branches were macroscopically studied for thrombotic material by opening the arteries as far distally as possible. No thrombotic material was observed in neither of the groups. Figure 2A shows a pulmonary graft not treated with heparin, and Figure 2B a pulmonary graft treated with heparin.