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Endovenous obliteration versus conventionalstripping operation in the treatment of primaryvaricose veins: A randomized controlled trial withcomparison of the costs Tero Rautio, MD,a Arto Ohinmaa, PhD,b Jukka Pera¨la¨, MD, PhD,c Pasi Ohtonen, MSc,a
Timo Heikkinen, MD, PhD,a Heikki Wiik, MD,a Pasi Karjalainen, MD,d Kari Haukipuro, MD, PhD,a
and Tatu Juvonen, MD, PhD,a Oulu, Finland; and Edmonton, Canada
Objective: The aim of this randomized study was to compare a new method of endovenous saphenous vein obliteration
(Closure System, VNUS Medical Technologies, Inc, Sunnyvale, Calif) with the conventional stripping operation in terms
of short-term recovery and costs.
Methods: Twenty-eight selected patients for operative treatment of primary greater saphenous vein tributary varicose veins
were randomly assigned to endovenous obliteration (n ؍ 15) or stripping operation (n ؍ 13). Postoperative pain was
daily assessed during the 1st week and on the 14th postoperative day. The length of sick leave was determined. The
RAND-36 health survey was used to assess the patient health-related quality of life. The patient conditions were
controlled 7 to 8 weeks after surgery, and patients underwent examination with duplex ultrasonography. The comparison
of costs included both direct medical costs and costs resulting from lost of productivity of the patients. Costs that were
similar in the study groups were not considered in the analysis.
Results: All operations were successful, and the complication rates were similar in the two groups. Postoperative average
pain was significantly less severe in the endovenous obliteration group as compared with the stripping group (at rest: 0.7,
standard deviation [SD] 0.5, versus 1.7, SD 1.3, P ؍ .017; on standing: 1.3, SD 0.7, versus 2.6, SD 1.9, P ؍ .026; on
walking: 1.8, SD 0.8, versus 3.0, SD 1.8, P ؍ .036; with t test). The sick leaves were significantly shorter in the
endovenous obliteration group (6.5 days, SD 3.3 days, versus 15.6 days, SD 6.0 days; 95% CI, 5.4 to 12.9; P < .001, with
t test). Physical function was also restored faster in the endovenous obliteration group. The estimated annual investment
costs of the closure operation were US $3360. The other direct medical costs of the Closure operation were about $850,
and those of the conventional treatment were $360. With inclusion of the value of the lost working days, the Closure
treatment was cost-saving for society, and when 40% of the patients are retired (or 60% of the productivity loss was
included), the Closure procedure became cost-saving at a level of 43 operations per year.
Conclusion: Endovenous obliteration may offer advantages over the conventional stripping operation in terms of reduced
postoperative pain, shorter sick leaves, and faster return to normal activities, and it appears to be cost-saving for society,
especially among employed patients. Because the procedure is also associated with shorter convalescence, this new method
may potentially replace conventional varicose vein surgery. (J Vasc Surg 2002;35:958-65.)
In the Western countries, operations on varicose veins the procedure is associated with significant surgical mor- are among the most common surgical procedures. In Fin- land, approximately 220 varicose vein operations per Recurrence is common after primary greater saphenous 100,000 inhabitants are performed each year.1 The strip- varicose vein surgery. Rates as high as 40% at 5 years have ping operation is a relatively inexpensive day surgery pro- been reported, and approximately 20% of varicose vein cedure that needs no special instrumentation. Varicose vein operations are done for recurrent veins.3,4 Furthermore, surgery is regarded as a safe and minor procedure; indeed, reoperations also result in marked losses of productivity. InFinland, the average sick leave time after a stripping oper-ation has been 4 weeks (Statistics of the Finnish National From the Departments of Surgery,a Radiology,c and Anesthesiology,d Oulu Pension Office 1997). Therefore, the economic conse- University Hospital; and the Department of Public Health Sciences,University of Alberta.b quences of varicose vein surgery and its numerous recur- Supported by a grant from the University of Oulu, Finland.
rences for healthcare and whole society are high.
This issue has led to the development of mini-invasive Additional material for this article may be found online at www.mosby.
techniques to replace the traditional procedure of stripping Reprint requests: Tero Rautio, MD, Department of Surgery, Oulu Univer- of the greater saphenous vein (GSV). Endovenous obliter- sity Hospital, Kajaanintie 50, SF-90230, Finland (e-mail: tero.rautio@ ation (Closure System, VNUS Medical Technologies, Inc, Sunnyvale, Calif) is a new method in which a catheter is Copyright 2002 by The Society for Vascular Surgery and The American inserted percutaneously to treat the GSV insufficiency.5,6 The operative costs of this new technique are higher be- 0741-5214/2002/$35.00 ϩ 0 24/1/123096
doi:10.1067/mva.2002.123096
cause of the purchasing price of the device and the dispos- JOURNAL OF VASCULAR SURGERYVolume 35, Number 5 Rautio et al 959
Fig 1. Trial profile. GSV, Greater saphenous vein; LSV, lesser saphenous vein.
able catheters. On the other hand, the procedure is less ultrasonography. Veins with a curve greater than 90 de- invasive and may, therefore, result in shorter convalescence grees were considered to be unsuitable for endovenous and ability to resume work sooner, thus reducing the costs treatment because of obvious problems of passage of the of lost productivity. The purpose of this study was to fairly rigid catheter in abrupt curves. The diameter of the compare endovenous saphenous vein obliteration with vein was measured with the patient in a semisupine posi- conventional stripping operation in a randomized fashion tion. The clinical severity of the varicose disease was graded and to evaluate the outcome in terms of postoperative pain, according to the clinical, etiologic, anatomic, and patho- sick leave, health-related quality of life, and cost.
physiologic (CEAP) scoring system and its modifications,the venous clinical severity score, the venous segmental PATIENTS AND METHODS
disease score, and the venous disability score.7,8 The study protocol was approved by the Ethical Com- The trial profile is summarized in Fig 1. Originally, 36 mittee of the Medical Faculty of the University of Oulu, patients with isolated GSV reflux were enrolled. Three of and the study was performed according to the provisions of the selected patients discontinued the study because of an unsuitable schedule. The remaining 33 patients were ran- Patient selection. For patient enrollment, 121 con-
domized with the sealed envelope method.
secutive patients scheduled for surgical treatment of pri- After the randomization, however, another four pa- mary varicose veins at the Department of Surgery, Oulu tients withdrew because of disappointment with assign- University Hospital, underwent examination with color ment to the stripping group. Another patient withdrew duplex ultrasonography. Screening was done between Jan- after the randomization because of pregnancy.
uary and June 2000 (Appendix A, online only). A Valsalva’s Procedures. All the procedures were performed with
maneuver–induced reversal of blood flow lasting for at least standardized balanced general anesthesia. The endovenous 2 seconds was considered a sign of clinically significant obliterations were performed by a surgeon (T.R.) in collab- reflux. Patients suitable for day-case surgery with symptom- oration with a radiologist (J.P.). The investigators had atic, previously untreated, and uncomplicated GSV tribu- performed more than 30 VNUS Closure procedures before tary varicosis and isolated unilateral saphenophemoral junc- the start of the study. All the stripping operations also were tion (SFJ) and GSV trunk insufficiency were eligible for the performed by the same experienced general surgeon (T.R.) study. Patients with coagulopathy or multiple, tortuous, with the same team and in the same operating room during and large-diameter (Ͼ12 mm) GSV trunks were excluded.
November 2000. In addition, local phlebectomy with Oe- The tortuosity and diameter of the vein were assessed with sch hooks (Salzmann Medico, St Gallen, Switzerland) and, 960 Rautio et al
in case of teleangiectasis, microsclerotherapy (Glicerina, leave was routinely prescribed for 5 days and continued for Laboratorio Terapeutico MR srl, Florence, Italy) were per- as much as 2 weeks if necessary. If disability lasted for more than 2 weeks, the patient was scheduled for a control visit at The endovenous obliteration procedure was performed with the VNUS Closure system, for which the technical The patients underwent reexamination after 7 to 8 details have been described previously.6,7 The catheter with weeks with color duplex ultrasonography. The postopera- sheathed electrodes was inserted percutaneously with ultra- tive CEAP scores were recorded. The patients also were sound scan guidance into the GSV at the ankle level asked whether they were satisfied with the treatment and through a vascular sheath of 5F or 8F. Subsequently, the how long a sick leave was necessary in their own opinion.
catheter was passed up to the SFJ, and its correct position The outcome measures were the duration of sick leave, was controlled with intraoperative ultrasound scanning.
pain, health-related quality of life, and satisfaction with the Subcutaneous saline solution was infiltrated between the proximal GSV and the skin. The lower limb was elevated, Calculation of costs. For a cost analysis, the costs
and an elastic compression wrap was applied from the toes were divided into direct medical costs and indirect costs.
to the groin for exsanguination of the entire GSV. Supple- The direct medical costs consisted of fixed and variable costs mental manual compression was used at the groin region.
as seen in Table I. Indirect costs consisted of the value of lost The electrodes of the catheter were unsheathed, and the wall contact of the electrodes was tested with measurement Costs that could be assumed to be the same in both of the impedance of the catheter. Heparinized saline solu- procedures (eg, administrative work, energy, overhead) tion was administered through the central lumen to rinse were excluded. Operating times (“skin-to-skin”) and oper- the electrodes and to avoid thrombus formation. No ordi- ating room and recovery room times were measured in nary thrombosis prophylaxis was used. After the activation minutes and valued on the basis of the average salary of the treatment circuit, the wall temperature was allowed brackets and figures drawn from the hospital accounting to equilibrate at 85° C for 15 seconds. The catheter then system. Anesthesia and recovery room costs were estimated was slowly (ca 3 cm/min) withdrawn, with the temperature to be US $72 in both methods. Two specialists were within Ϯ3° C of the set temperature. The entire length of involved in the VNUS operation compared with one in the the femoral segment of the GSV thus was treated. To avoid conventional alternative. The hourly salary of a specialist damage to the saphenous nerve, the treatment was limited was $32. Investment costs included only the cost of the to the area above the medial condyle of the tibia. Immedi- generator and were allocated to 5 years with a 5% social ately after the treatment, the treated segment was evaluated discount rate. The basic instrumentation was the same in with color Doppler ultrasound scan to ensure proper oc- both operations. The VNUS Closure specific costs further clusion of the vein. This evaluation also allowed the option included the price of the catheter and the rent of the of retreatment of the unoccluded segment immediately.
ultrasound scan equipment. The other costs of day surgery The length of the treated GSV segment and the pullout were assumed to be the same. The postoperative costs At the beginning of the stripping operation, the groin included the additional follow-up visits and telephone con- was dissected to fully expose the SFJ. The side branches of sultations needed to lengthen sick leaves. The patient med- the GSV at the SFJ were divided and ligated. After local ical costs were assumed to be the same, with the exception phlebectomy, the GSV was stripped from just below the of the analgesics used during the first 2 weeks and the travel knee to the groin with the conventional flexible and dispos- costs as a result of the follow-up visits. The units and the able Venostrip (Aesculap AG & CO, KG, Tuttlingen, Ger- unit values of the cost factors and the sum totals are shown many) with a 9-mm olive. The calf and groin incisions were in Table I. The indirect costs were calculated as costs caused sutured with 5/0 nonabsorbable interrupted sutures.
by lost productivity because of sick leave. The value of the Postoperative care and follow-up examination.
lost workdays was assessed on the basis of the average wage Postoperative compression of the treated leg was standard- level in Finland in the year 20009 plus 50% nonwage costs ized. Knee and groin length antiembolism stockings were for social security and other worker-based costs. A 5-day applied immediately after the treatment and kept for 7 days.
work week was used in the calculation of indirect costs.
No limitations were placed on mobilization, and the pa- Statistical analysis. The serial measurements were
tients were encouraged to walk as soon as possible.
summarized with calculation of the average score over the The patients recorded postoperative pain at rest, on study period for each patient. The change from the baseline standing, and on walking with a visual analogue scale health-related quality of life scores to those recorded at 1 (range, 0 to 10) on a daily basis during the 1st week and on week and 4 weeks after surgery was determined, and the the 14th postoperative day. The short-term RAND-36 other intergroup comparisons were made with Student t generic health-related quality of life questionnaire (validat- test (TT) or with the Mann-Whitney U test as appropriate.
ed for Finland) was used to measure health status before the The categoric values were analyzed with the ␹2 or Fisher procedure and 1 and 4 weeks after surgery. The patients exact test. Kendall rank correlation coefficient (␶) and co- also were asked to record the need and use of oral ibuprofen efficient of determination (␶2) were calculated (Appendix (the number of 600-mg tablets) or other analgesics. A sick JOURNAL OF VASCULAR SURGERYVolume 35, Number 5 Rautio et al 961
Table I. Costs of VNUS Closure and conventional surgery in treatment of primary varicose veins (US dollars*)
Sensitivity analysis was done to estimate the effects of Table II. Patient characteristics
the changes in the main background variables. The influ-ence of indirect costs was tested with 50% of the estimated costs. The influence of the retired patients on the indirect costs was tested with the assumption that 25% or 40% of thepatients were retired. The scenario with one specialist per- forming the whole operation and no discounting of invest- ment costs also was analyzed. Two-way sensitivity analysis was performed, with the assumption that one specialist performed the operation and that the indirect costs ac- counted for 50%, 60%, or 75% of the estimated costs. The influence of the possible higher investment costs in the United States were tested with $18,000 as a cost for the generator and $446 for the catheter (values from US ex- Twenty-eight patients were allocated into the treat- EOG, endovenous obliteration group; SOG, stripping operation group; ment groups and completed the study. Fifteen patients GSV, greater saphenous vein; VCSS, venous clinical severity score; VSDS, were in the endovenous obliteration group, and 13 patients venous segmental disease score; VSD, venous disability score.6 were in the stripping group (Fig 1).
The basic characteristics of the patients were similar in both groups, with the exception of the higher mean age in and operating room time (115 minutes, SD 18.3, versus 99 the stripping group (P ϭ .045, with TT; Table II). One minutes, SD 12.9, P ϭ .01) were significantly longer in the patient retired after randomization but was not withdrawn endovenous obliteration group. These times are used in the cost analysis presented in Table I. The differences in the The procedures were performed on a day surgery basis.
recovery room times (obliteration: 227 minutes, SD 57.6; As evidence of successful standardization of general anes- versus stripping: 198 minutes, SD 40.7; P ϭ .16) were not thesia, no significant differences were seen in the bispectral index, sevoflurane minimum alveolar concentration, imme- The mean follow-up time was 50 days in both groups.
diate recovery from anesthesia, or home readiness. Two In all cases, endovenous obliteration was successfully per- patients (one from each group) had to stay in the hospital formed with no duplex scan– detectable flow in the treated overnight because of social reasons.
GSV segments. Consequently, the postoperative venous The mean operation time (75 minutes, standard devi- segmental disease score fell from 1 to 0 in all patients of this ation [SD] 16.6, versus 57 minutes, SD 11.0, P ϭ .003) group. One patient in the stripping group had reflux in an 962 Rautio et al
Table III. Postoperative complications after closure
procedure and stripping operation for primary varicose
veins
accessory branch of GSV, which resulted in a score of 1 aftersurgery. The average decrease of the venous clinical severityscore was 5.1 (SD, 1.5) in the endovenous obliterationgroup and 4.4 (SD, 1.1) in the stripping group (P ϭ .19,with TT). The postoperative venous disability score was 0in all but two patients (one from each group), who occa-sionally needed compression stockings while working.
Intraoperative complications consisted of a painful groin hematoma (stripping group) and three small second-degree thermal skin injuries (endovenous obliterationgroup). The burns did not need specific treatment andhealed completely. These three patients, however, had ten-derness and induration over the course of the treated GSVsegment. In one of these cases, thermal burn scar wasnoticed at the time of follow-up visit and was considered asa late complication (Table III). Saphenous nerve paresthesis,defined as numbness or dysesthesia, which was limited tothe thigh, developed after two endovenous procedures andthree stripping operations. On the whole, minor postoper-ative complications were common in both groups, withseven in the endovenous obliteration group and seven inthe stripping operation group (Table III). None of thecomplications caused any need for treatment or resulted inincreased costs.
The average visual analogue scale pain scores at rest, on standing, and on walking were significantly lower in theendovenous obliteration group than in the stripping group Fig 2. Median pain scores with 25th and 75th percentiles at rest
(rest: 0.7, SD 0.5, versus 1.7, SD 1.3, P ϭ .017; standing: and on standing and walking. (Daily P values were calculated with 1.3, SD 0.7, versus 2.6, SD 1.9, P ϭ .026; walking: 1.8, SD Mann-Whitney U test). EOG, Endovenous obliteration group; 0.8, versus 3.0, SD 1.8, P ϭ .036; with TT). The differ- SOG, stripping operation group; VAS, visual analogue scale.
ences were especially clear from the 5th to the 14th post-operative day (Fig 2). Patients in the endovenous oblitera- The changes in the health-related quality of life param- tion group also needed less analgesics than those in the eters are shown in Table IV. Physical function was restored stripping group (average daily number of 600-mg ibupro- faster in the endovenous obliteration group. All patients fen tablets, 0.4, SD 0.49, versus 1.3, SD 1.09, P ϭ .004, were satisfied with the treatment, but one patient in the endovenous obliteration group and four in the stripping The sick leaves were significantly shorter in the en- group were dissatisfied with the cosmetic outcome.
dovenous obliteration group (6.5, SD 3.3, versus 15.6, SD The cost analysis results showed that the annual cost of 6.0; 95% CI, 5.4 to 12.9; P Ͻ .001, with TT). An even the VNUS Closure generator was about $3400, which more distinct difference was seen in the patients’ own would have meant $120 per operation if all of our trial assessment of the length of the required sick leave (6.1, SD operations had been performed with the Closure procedure 4.4, versus 19.2, SD 10.0; 95% CI, 7.2 to 18.9; P ϭ .001, (Table I). The operative costs of the endovenous oblitera- with TT). A positive correlation between age and sick leave tion were significantly higher, mainly because of the cost of (␶ ϭ 0.37; P ϭ .012) was observed (Appendix B, online the catheter. However, the combined cost effect of the additional specialist and the rent of the ultrasound scan JOURNAL OF VASCULAR SURGERYVolume 35, Number 5 Rautio et al 963
Table IV. Quality of life indexes (RAND-36), at baseline and 1 week and 4 weeks postoperatively after surgery
Median difference from baseline score (baseline-postoperative value) Role functioning/emotional 100 (100-100) 100 (67-100) *Comparison between endovenous obliteration and stripping operation groups (with Mann-Whitney U test).
EOG, Endovenous obliteration group; SOG, stripping operation group.
Fig 3. Sensitivity analysis of costs of VNUS Closure and conventional surgery in treatment of primary varicose veins
in different numbers of patients per year (US dollars).
equipment was much smaller. The effects of the longer retired, the Closure operation was cost saving (at least 20 operation times in the endovenous obliteration were patients). The break-even point for 40% of retired patients quite modest. Although all of the postoperative medical (60% of indirect costs) was 43 patients. High investment costs were somewhat higher in the conventional surgery costs for the generator and the catheter would have raised group, they did not have any major effect on the total the Closure cost curves about $370. In the basic alterna- variable costs of the alternatives. Although the variable tives, the Closure operation would then have been cost costs of the conventional operations were about half of saving at the level of 40 patients per year.
the endovenous obliteration costs, the total societal costsof the conventional operation were at least $300 higher DISCUSSION
than those of the Closure procedure (Fig 3). Thus, the This study is the first randomized trial comparing en- indirect costs had a significant impact on the total soci- dovenous obliteration with traditional stripping operation in the treatment of primary varicose veins. According to our The sensitivity analysis results showed that the use of findings, endovenous obliteration resulted in less postop- one specialist in the operation did not change the cost erative pain, shorter sick leaves, and faster recovery of curves significantly (Fig 3). The effect of use of only half of physical function than traditional surgery. Closure proce- the indirect costs was great, especially in the conventional dure has higher operating costs but involves potential eco- group. If half of the indirect costs were included in the cost nomic advantages for employed patients because of their analysis, the endovenous obliteration became cost-saving after about 150 operations per year, with one specialist for The idea of use of endovenous electrosurgical devices the operation. The influence of the retired patients on the for venous wall collagen denaturation is not new. During indirect costs was also great. If 25% of the patients were the past few decades, sporadic reports concerning proce- 964 Rautio et al
dures to eliminate truncal or tributary varicosities with have a significant influence on the results of the cost anal- monopolar electrosurgical desiccation have been pub- lished.10-14 The system used in this study (Closure System) Because the differences in the postoperative pain and was on the basis of an advanced method, including precise other complications lasted for only a few weeks, cost com- heating, feedback controlled with the venous wall temper- parison and cost minimization analyses are appropriate methods of economic evaluation.15 In this case, the The procedures were equally efficient in elimination of method is closer to cost comparison analysis because of the reflux in the treated GSV segments. The postoperative minor differences in the effectiveness of the treatments, at changes in CEAP classification did not differ, either. The least according to the short-term results.
overall complication rates were similar in the two groups, Varicose vein recurrence, defined as the proportion of although a difference was found in the distribution of the patients seeking further treatment after apparently ade- quate surgery, is seen in at least 20% to 30% of the cases and The endovenous obliteration procedure duration was tends to increase over time.16 This causes an extra financial 18 minutes longer than the conventional procedure. This burden on general surgical units and induces costs for trial was performed partly during the learning curve of society. Endovenous obliteration omits high ligation and endovenous obliteration because our surgical team per- leaves accessory tributaries of the SFJ, which can be re- formed only 30 procedures before the initiation of this garded as a risk for recurrence. However, with Closure study and the experiences from other centers with the treatment without SFJ ligation, the normal venous drain- procedure were also dated back only about 2 years. This age of the lower abdominal and pudendal tissues is pre- short experience time could have influenced the operating served. This may reduce the stimulus to neovasculariza- times and some of the short-term results (ie, complications).
tion.17 Because angiogenesis is regarded as an important In this study, the minimally invasive nature of the cause of recurrent reflux,18-21 endovenous obliteration mayactually reduce the risk of recurrent varicosities. Long-term endovenous obliteration technique resulted in reduced follow-up periods are, however, needed to better evaluate postoperative pain and use of analgesics. Almost half of whether the recurrence rate could be reduced with the the patients in the stripping group had pain and tension in the thigh 2 weeks after the operation, which seemed to be In conclusion, our results indicated that endovenous the main cause of prolonged sick leaves among these pa- obliteration may offer an advantage over conventional tients. In addition, the pain disturbed knee motion and stripping operation in terms of reduced postoperative pain, walking, thus delaying the recovery of normal physical shorter sick leaves, and faster return to normal activities. We function. However, the lack of blinding in this study may also conclude that endovenous obliteration was more ex- likely have had some influence on patients’ subjective eval- pensive for the hospital. In this study, the total costs, which uation of postoperative pain. The patients were slightly also included the costs incurred by society because of sick older in the stripping group, and a positive correlation leaves, were no higher than the total costs of the conven- between age and sick leave emerged. According to the tional stripping operation. More information is needed on coefficient of determination, however, age explained only the long-term results and recurrence rates, and larger stud- 14% of the length of the sick leave. Thus, we believe that the ies are needed to determine the precise role of this proce- results were not distorted on the account of this random- dure in the treatment of primary varicose veins. A thorough assessment of varicose vein surgery would necessitate a The patient’s subjective opinions about the appropriate long-term cost-effectiveness or cost-benefit analysis of duration of the sick leave were consistent with the sick leaves actually prescribed. Furthermore, the changes in thehealth-related quality of life parameters, physical function- We thank the staff of the Day Surgery and Interven- ing, and bodily pain at 1 week after the procedures support tional Radiology Units of the Oulu University Hospital for the reliability of the finding concerning significantly shorter sick leaves after endovenous obliteration (Appendixes Cand D, online only).
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15. Drummond M, OЈBrien B, Stoddart G, Torranca G. Methods for the economic evaluation of health care programmes. 2nd edition. Oxford: Additional material for this article may be found online Authors requested to declare conditions of research funding
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