Independent risk factors affecting hemorrhage in percutaneous nephrolithotomy: Retrospective study

The perioperative and postoperative concern in percutaneous nephrolithotomy (PNL) is bleeding. Disease-related conditions (such as stone size, stone HU, tract number, and diameter) affecting this situation were determined. To determine independent risk factors that may affect the amount of hemorrhage in PNL.

A total of 308 adult patients (211 men, 97 women) undergoing the PNL procedure were included in the study. Renal anatomy and stone size were evaluated using non-contrast thin-section computed tomography (NCCT). NCCT was used to assess Hounsfield unit (HU) values of kidney stones, presence of atheroma plaque and obesity. The difference between preoperative hemoglobin (Hgb) values and postoperative 1st day Hgb values was recorded. This variation was evaluated for the effect of gender, age, atherosclerotic vein disease, urine pH and density, leukocyte count, lymphocyte count, neutrophil count (NEU), platelet count, mean platelet volume (MPV), neutrophil lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), stone volume, HU, and obesity.

The mean Hgb variation was identified as 2.1 (standard deviation: 1.6). There were positive, significant, and weak correlations between the Hgb variation with NEU (P=0.019), MPV (P=0.000), NLR (P=0.005), stone volume (P=0.041) and HU (P=0.024) values. There was a negative significant and weak correlation between Hgb variation and PLT (P=0.022). No effects at significant levels were identified for gender (P=0.078), presence of atheroma plaque (P=0.949), obesity (P=0.869), age (P=0.686), urine pH (P=0.746), urine density (P=0.421), and PLR (P=0.855) on Hgb variations.

In addition to HU and stone volume, NEU count, MPV, NLR and PLT count may be used as independent risk factors to predict blood loss during PNL.