Objectives: Blood loss in transurethral resection of prostate (TUR-P) operation is estimated by the difference between pre- and post-operative hemoglobin (Hb) concentration. The authors introduced a novel practical method to estimate blood loss in the patients who were surgically managed with TUR-P operation.
Material and Method: Complete blood count was collected pre-operative, immediate post-operative, and 24-hour post-operative to determine red blood cells and Hb concentration. Hemoglobin of irrigating fluid was measured by standard spectrophotometry and blood loss was estimated by the authors’ calculation. Irrigating fluid was frozen and thawed to completely hemolyse the red blood cells, then it was tested by urine-strips and calculated for red cells using estimating cell ranges given by the product’s prescription. The correlation between these indicators was evaluated.
Results: Calculated blood loss detected by spectrophotometric method has no correlation with immediate post-operative or 24-hour post-operative Hb concentration. However, it had a significant positive correlation with calculated blood loss by urine-strip technique (r = 0.897, p = 0.01).
Conclusion: Urine-strip method can be used to estimate total blood loss in irrigating fluid in patients with TUR-P operation. This is practical and useful in immediate post-operative evaluation of blood loss to consider the need of blood transfusion.

Keywords: Estimation of blood loss, Transurethral resection of prostate, Urine-strip, Spectrophotometry, Hemoglobin, Irrigating fluid