title: Are coagulation studies necessary before percutaneous nephrostomy?
abstract: OBJECTIVE
  Performance of coagulation studies for patients undergoing percutaneous nephrostomy (PCN) has been advocated by some investigators. We performed a retrospective study to assess this practice.
  
  
  METHODS
  The medical records of 180 patients subjected to PCN for various reasons between October 1991 and July 1998 were reviewed. This represents a subset of patients in whom PCN was performed by an experienced interventional radiologist at our institution. Patients were excluded if they had a history of active liver disease, hematologic or bleeding disorder, current use of heparin or warfarin, or platelet count <100,000. The remaining 160 patients were separated into two groups. Group 1 consisted of 153 patients with a normal prothrombin time (PT) and partial thromboplastin time (PTT). Group 2 comprised 7 patients with an abnormal PT or PTT. Demographic and laboratory data including PT, PTT, complete blood, and platelet counts were analyzed to determine if a hemorrhagic complication could be predicted by an abnormal PT or PTT.
  
  
  RESULTS
  In group 1 the mean PT was 12.2 seconds and the mean PTT was 25.0 seconds; in group 2 the mean PT was 13.9 seconds and the mean PTT was 30.3 seconds. The hemorrhagic complication rates were not statistically different between the two patient cohorts (p = .203). Demographic and standard laboratory data were not predictive of abnormal coagulation parameters.
  
  
  CONCLUSIONS
  Screening coagulation studies are unnecessary in the standard patient subjected to PCN.
authors.affiliation: Department of Urology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1094, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Martin
authors.forename: C J
authors.initials: CJ
authors.lastname: Rosser
authors.forename: R F
authors.initials: RF
authors.lastname: Linebach
authors.forename: D L
authors.initials: DL
authors.lastname: McCullough
authors.forename: D G
authors.initials: DG
authors.lastname: Assimos
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001778:Blood Coagulation Disorders / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D008403:Mass Screening / Q000379:methods; D008875:Middle Aged; D015999:Multivariate Analysis; D009403:Nephrostomy, Percutaneous; D012189:Retrospective Studies; D018570:Risk Assessment; D014570:Urologic Diseases / Q000150:complications / Q000175:diagnosis / Q000628:therapy*