Venous Blood Gases of Varicocele Veins: Correlation with Testicular Blood Flow and Semen Quality in Varicocele Patients.

OBJECTIVE: To investigate venous blood gases (VBG) in varicocele veins and correlation with semen and testicular blood flow.

MATERIAL AND METHODS: Twenty-seven infertile patients, undergoing left microsurgical varicocelectomy, at Urology/Andrology Department of a teaching hospital, were included. Before surgery semen parameters were recorded and scrotal color doppler ultrasonography (CDUS) done to measure peak systolic velocity (PSV) resistive index (RI) of sub capsular and intra parenchymal branches of testicular artery. During surgery, blood sample was drawn from varicocele veins and a peripheral arm vein. VBGs were estimated and compared with each other.

RESULTS: The pH was lower (p<0.001) in internal spermatic vein (p<0.01) compared to external spermatic and peripheral veins. The partial pressure of oxygen (pO2) and oxygen saturation (sO2) were higher (p<0.001) in internal spermatic vein (p<0.01) compared with peripheral vein. However, HCO3 was lower (p<0.05) in both veins compared to the peripheral vein. The partial pressure of carbon dioxide (pCO2) was similar (p>0.05) in three veins. The pO2 of internal spermatic vein had negative correlation (r=-0.42; p< 0.05) with PSV of intra parenchymal arteries. No such correlation was observed for external spermatic vein or peripheral vein.

CONCLUSIONS(S): Internal spermatic veins had higher oxygen level, lower pH and bicarbonate levels compared to peripheral veins. External spermatic veins had lower HCO3 but other VBGs were similar to peripheral veins. The shift of internal spermatic vein VBGs towards arterial blood may be due to arteriovenous communications of spermatic cord. It may be a missing link to understand the pathophysiology of varicocele.