title: Factors affecting bleeding during percutaneous nephrolithotomy: single surgeon experience.
abstract: OBJECTIVE
  To investigate variables that affect bleeding during percutaneous nephrolithotomy (PCNL), focusing on the experience of a single surgeon.
  
  
  METHODS
  The records of 649 PCNL procedures that were performed by the same surgeon were reviewed retrospectively. The effect of surgical experience; patient and stone-related factors, including age, sex, hypertension, and diabetes, serum creatinine level, history of ipsilateral renal procedures, stone surface area and type, degree of hydronephrosis, preoperative hemoglobin level; operative factors, such as the calix of puncture, number of accesses, operative time; and intraoperative complications, such as pelvicaliceal system perforation on bleeding (described as decrease in hemoglobin level and need for blood transfusion), were investigated. For statistical assessment, univariate analyses and multivariate stepwise regression analyses were used.
  
  
  RESULTS
  A 92.3% success rate was achieved after one session PCNL. The overall blood transfusion rate was 10.8%. The number of accesses, stone type, diabetes, preoperative hemoglobin level, and operative time were the most important factors for blood transfusion requirement. In the receiver operating characteristic curve, the best cutoff point of operative time was 58 minutes for the blood transfusion requirement. Multivariate stepwise regression analyses showed that there was an association between diabetes, operative time, number of accesses, and stone type with the decrease in hemoglobin levels. No correlation between surgical experience and decrease in hemoglobin level as well as blood transfusion necessity was found.
  
  
  CONCLUSIONS
  Depending on the results achieved by a single surgeon, multiple access tracts, staghorn calculi, presence of diabetes, and prolonged operative time, but not surgical experience, significantly increased blood loss during PCNL.
authors.affiliation: Department of Urology, Haseki Training and Research Hospital, Istanbul, Turkey.
authors.forename: Tolga
authors.initials: T
authors.lastname: Akman
authors.forename: Murat
authors.initials: M
authors.lastname: Binbay
authors.forename: Erhan
authors.initials: E
authors.lastname: Sari
authors.forename: Emrah
authors.initials: E
authors.lastname: Yuruk
authors.forename: Abdulkadir
authors.initials: A
authors.lastname: Tepeler
authors.forename: Muzaffer
authors.initials: M
authors.lastname: Akcay
authors.forename: Ahmet Yaser
authors.initials: AY
authors.lastname: Muslumanoglu
authors.forename: Ahmet
authors.initials: A
authors.lastname: Tefekli
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016063:Blood Loss, Surgical; D001803:Blood Transfusion; D002648:Child; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000601:surgery; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D016896:Treatment Outcome; D055815:Young Adult