title: A new classification of inferior vena cava thrombus in renal cell carcinoma could define the need for cardiopulmonary or venovenous bypass.
abstract: BACKGROUND
  Although the level of inferior vena cava (IVC) thrombus governs the type of surgical approach, there is no consistency in reporting the levels of IVC thrombus in the literature. This prospective study illustrates a simple three-level classification based on the need for clamping hepatoduodenal ligament and venovenous or cardiopulmonary bypass.
  
  
  METHODS
  Between January 2010 and June 2014, 30 patients of renal mass with renal vein and/or IVC thrombus were treated after classifying the IVC thrombus into three levels on the basis of need for clamping the hepatoduodenal ligament. After excluding renal vein thrombi, level I was described as thrombus located caudal to the hepatic vein. Level II included all retrohepatic, suprahepatic infradiaphragmatic or supradiaphragmatic thrombi reaching till the right atrium. Atrial thrombi were categorized as level III. Level I and II thrombi were managed without venovenous or cardiopulmonary bypass. Level III thrombus required cardiopulmonary bypass.
  
  
  RESULTS
  Of 26 patients with thrombus, 13 had level I thrombus. Of eight cases with level II thrombus, three were retrohepatic, three were suprahepatic infradiaphragmatic and two were supradiaphragmatic. All were removed successfully. Of five patients with level III thrombus, three were operated with cardiopulmonary bypass while the remaining two patients were too sick to be taken up for surgery. The median hepatoduodenal ligament clamp time was 10 min. One patient with level II thrombus had transient liver enzyme elevation.
  
  
  CONCLUSIONS
  Renal vein thrombus should not be categorized as level I thrombus. Level II thrombus, irrespective of its relation to the diaphragm, could be managed without venovenous or cardiopulmonary bypass.
authors.affiliation: Department of Urology and Renal Transplantation, King George Medical University, Lucknow, India.
authors.forename: Anil
authors.initials: A
authors.lastname: Mandhani
authors.affiliation: Department of Urology and Renal Transplantation, King George Medical University, Lucknow, India.
authors.forename: Nitesh
authors.initials: N
authors.lastname: Patidar
authors.affiliation: Department of Radio Diagnosis, King George Medical University, Lucknow, India.
authors.forename: Pallavi
authors.initials: P
authors.lastname: Aga
authors.affiliation: Department of Cardiothoracic and Vascular Surgery, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Shantanu
authors.initials: S
authors.lastname: Pande
authors.affiliation: Department of Anesthesia, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
authors.forename: Prabhat
authors.initials: P
authors.lastname: Tewari
keywords: Cardiopulmonary bypass; inferior vena cava thrombus; renal cell carcinoma; venovenous bypass