title: High-frequency oscillatory ventilatory support during CT-guided percutaneous cryotherapy of renal masses.
abstract: OBJECTIVE
  Computed tomography (CT)-guided percutaneous procedures are often made more difficult due to the movement of the kidney during respiration. Here we examine the use of high-frequency oscillatory ventilation (HFOV), which eliminates the movement of the kidney, potentially making cryoprobe access to the kidney simpler and possibly more efficient.
  
  
  METHODS
  We compared seven CT-guided percutaneous procedures using a single cryoprobe and either standard mechanical ventilation (MV) (n=4) or HFOV (n=3). The variables studied included: total time of patient intubation, operative time, overall duration of interventional radiology (IR) suite time, change in hematocrit, narcotic use, and complications. The ease of the procedure was rated on a subjective scale from 1 to 3.
  
  
  RESULTS
  The total intubation time remained nearly identical at 210 minutes for HFOV and 208 minutes for MV, but surgeon procedural time decreased by 31 minutes in the HFOV group (HFOV=99 minutes and MV=130 minutes) (P=0.40). Total IR time was 225 minutes for HFOV compared to 212 minutes for the MV group (P=0.63). There were no significant differences in the postoperative hematocrit, creatinine, or narcotic use between the two groups. There were no complications related to the procedure or anesthesia in either group. Both urology attending physicians and the interventional radiologist noted that the procedure seemed easier with HFOV.
  
  
  CONCLUSIONS
  HFOV may shorten the actual procedural time required to perform cryoablation, likely due to the elimination of renal movement during the procedure, thereby facilitating targeting and access to the renal mass. In this initial experience, patients tolerated HFOV without incident, and the operating surgeons found it easier to perform the procedures.
authors.affiliation: Department of Urology, University of California, Irvine, California 92868, USA.
authors.forename: Shawn M
authors.initials: SM
authors.lastname: Beck
authors.forename: David S
authors.initials: DS
authors.lastname: Finley
authors.forename: Geoffrey N
authors.initials: GN
authors.lastname: Box
authors.forename: Duane J
authors.initials: DJ
authors.lastname: Vajgrt
authors.forename: Anne B
authors.initials: AB
authors.lastname: Wong
authors.forename: Debra E
authors.initials: DE
authors.lastname: Morrison
authors.forename: Nathan
authors.initials: N
authors.lastname: Kudrick
authors.forename: Elspeth M
authors.initials: EM
authors.lastname: McDougall
authors.forename: Ralph V
authors.initials: RV
authors.lastname: Clayman
mesh_terms: D001291:Attitude of Health Personnel; D003404:Creatinine / Q000032:analysis; D003452:Cryosurgery / Q000379:methods*; D005240:Feasibility Studies; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006612:High-Frequency Ventilation; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D015641:Radiography, Interventional; D012121:Respiration, Artificial; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D006454:Hemoglobins; D003404:Creatinine