Establishment of a prediction model for haemorrhage after semi-tubeless PCNL

Abstract Objectives : To establish a prediction model to predict the risk of severe hemorrhage after semi-tubeless percutaneous nephroscopy(PCNL). Methods: The data of 464 patients (464 semi-tubeless PCNL procedures) were retrospectively analyzed at Shenyang Red Cross Hospital from January 1st,2016 to January 1st,2023.The following factors were analyzed: blood pressure,stone score,expansion method,visualization, Guys grades,avasculararea,diabetes,age,history of PCNL,duration,solid kidney,preoperative nephrostomy ,number of channel,channel size,BMI and gender.We established a prediction model by using the data above and we collect 50 additional patients as the test group to verify the accuracy of the model. Results: For all the 464 patients, 91 patients had postoperative haemorrhage and 373 had no haemorrhage.The average hemoglobin drop for all the procedures was 23 .5±6.1g/L (range 20.1–38.1g/L), whereas the average hematocritdrop was 5.46±4.08% (range 0.4%–29%).We collect 16 variables.Univariate regression analysis was performed in SPSS and independent factors(P<0.2)affecting haemorrhage were selected.Gender(P=0.301),dilation method(P=0.455) and age(P=0.214) are excluded.We performed a logistic regression in the R studio.The nomogram was constructed to present the prediction model and the decision curve analysis(DCA) was conducted to evaluate the model efficiency. Conclusion: For patients after semi-tubeless PCNL, High blood pressure,high stone score,non-visualization,high Guys grade,non-avascular area,diabet,advanced age,history of PCNL,long operation time ,solid kidney,non-preoperative nephrostomy,multiple channels,large channel size and high BMI are alarming variables for haemorrhage after semi-tubeless PCNL.Preoperative assessment of haemorrhage risk is necessary.