Successful Treatment of Early Postoperative Aortic Graft Infection by Percutaneous Catheter Drainage David J. Glickerman, MD, Peter J. Dickhoff, MD, R. Eugene Zierler, MD, John D. Harley, MD, and David L. Dawson, MD, Seattle, Washington

Successful treatment by percutaneous catheter drainage of an acute aortic graft infection with an associated pancreatic fistula is reported. Percutaneous catheter drainage can be considered in selected patients when the risk of reoperation is deemed unacceptable or when other reasonable treatment options do not exist. (Ann Vasc Surg 1996;10:486-489.)

The incidence of p r o s t h e t i c v a s c u l a r graft infection r a n g e s f r o m 1% to 6%. 1 M o r t a l i t y f r o m aortic graft i n f e c t i o n m a y be as h i g h as 50% w i t h significant m o r b i d i t y f r o m l i m b loss. 26 Diagnosis of aortic graft i n f e c t i o n is b a s e d o n a c o n s t e l l a t i o n of clinical findings a n d c o n f i r m e d b y i m a g i n g studies a n d culture of fluid s a m p l e s . ~ The m a i n stay of t r e a t m e n t is graft excision w i t h extraa n a t o m i c revascularization. ~6 CT- a n d ultras o u n d - g u i d e d p e r c u t a n e o u s c a t h e t e r d r a i n a g e is effective in the m a n a g e m e n t of i n t r a - a b d o m i n a l abscesses. ~9 CT h a s b e e n useful for d e t e c t i n g '°-~6 infected grafts a n d guiding p e r c u t a n e o u s treatm e n t in selected cases. 17~9 W e report a case of early p o s t o p e r a t i v e i n f e c t i o n of a n aortobi-iliac graft a s s o c i a t e d w i t h a perigraft abscess a n d p a n creatic fistula, w h i c h w a s successfully t r e a t e d by percutaneous catheter drainage and prolonged antibiotic t h e r a p y .

CASE R E P O R T A 63-year-old obese m a n presented in hemorrhagic shock with acute abdominal and back pain. Examination showed him to be diaphoretic, hypotensive, and tachycardiac. He had a tender, nonpulsatile mass in the left lower quadrant. In the emergency room a rapidly performed abdominal ultrasound examination con-

From the Department of Radiology and the Division of Vascular Surgery, Seattle Division Veterans Affairs Puget Sound Health Care System and the University of Washington, Seattle, Wash. The views expressed herein are those of the authors and do not represent the views of the Department of Defense or other departments of the U.S. government. Reprint requests: David J. Glickerman, MD, Seattle Division Veteraas Affairs Puget Sound Health Care System Radiology Service (114), 1660 S. Columbian Way, Seattle, WA 98108. 486

firmed the presence of an 8 cm abdominal aortic aneurysm. Emergency laparotomy revealed a 6 x 5 x 8 cm infrarenal abdominal aortic aneurysm that had ruptured through its anteroinferior surface. Control was achieved by manual compression at the level of the diaphragm, and an infrarenal clamp was placed. A bifurcated 24 x 12 m m woven double-velour Dacron graft was placed, with proximal anastomosis immediately below the renal arteries. Distal anastomoses were performed to the common iliac arteries. Blood loss was extensive requiring intraoperative replacement with 14 L of crystalloid and 10 L of blood products including 10 units of whole blood and 2.6 L of autotransfusion. The patient's medical history was significant for several reasons. Five years previously he had suffered a left hemispheric cerebral infarct with residual mild right hemiparesis and nonfluent aphasia. He had poorly controlled hypertension and significant symptomatic coronary artery disease. A remote inferior wall myocardial infarction had compromised ventricular function; recent radionuclide studies demonstrated an ejection fraction of 38% with hypokinesis of the inferior and lateral walls and akinesis of the apex. A 60 pack-year smoking history and multiple prior documented episodes of pulmonary embolism had produced both restrictive lung disease and moderately severe obstructive airway disease (FEV~ = 1.7 L; FVC = 2.6 L). During the first 2 postoperative days the patient required continued fluid replenishment to maintain hemodynamic stability. On postoperative day 2 he passed three guaiac-positive stools. His temperature was 38 ° C and his white blood cell (WBC) count ranged from 10,000 to 14,000/ml. Serial sigmoidoscopy over a 36-hour period documented a worsening area of circumferential mucosal sloughing and ischemia. On postoperative day 4 a left colectomy with transverse colostomy and a Hartmann's pouch was performed. The operation was complicated by a splenic capsular tear requiring splenectomy. On postoperative day 10 the patient developed sepsis with a m a x i m u m temperature of 39 ° C and WBC count of 25,000/ml. Cultures were obtained and broadspectrum antibiotics were initiated. Blood cultures

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grew coagulase-negative Staphylococcus and all intravascular lines were changed. The patient remained septic, and a CT scan on postoperative day 12 revealed fluid around the graft and a large area of fluid collection just beneath the left anterior abdominal wall. A large amount of fluid just beneath the abdominal wall was aspirated under CT guidance, a catheter was placed, and 2.4 L of purulent fluid was removed. Culture of the aspirate grew coagulase-negative Staphylococcus and Bacteroides species. WBC count decreased from 29,300 to 18,600/ml; however, the patient continued to have a low-grade fever despite culture-directed intravenous antibiotic therapy with imipenem and vancomycin. On postoperative day 20 a CT scan demonstrated an increased amount of perigraft fluid beginning just below the aortic anastomosis and extending into the pelvis. CT-guided aspiration of the perigraft fluid also grew Bacteroides. By this time the patient was 40 kg over his preoperative weight, was ventilator dependent, and had multiple open wounds from two recent laparotomies. Cardiac and pulmonary reserve was minimal and it appeared that the patient would not survive operative removal of the aortic graft with axillobifemoral bypass grafting and oversewing of the aorta and iBac arteries. In addition, the proximal location of the aortic anastomosis would probably result in occlusion of the renal artery orifices if the distal aorta was oversewn after graft excision. For these reasons we elected to continue nonoperative therapy. On postoperative day 23 a 14 F sump catheter was placed into the area of perigraft fluid collection under CT guidance, and 700 ml of serosanguineous fluid was drained (Fig. 1). Cultures were positive for [3-1actamase-positive Bacteroides thetaiotaomicron. Follow-up CT on postoperative day 27 demonstrated a splenic bed fluid collection, which was drained with an 8 F pigtail catheter producing 140 ml of purulent fluid that subsequently grew Bacteroides and

Case reports 487

contained high levels of amylase indicative of a pancreatic fistula. Standard drainage catheter irrigation was instituted, and over the following 2 weeks drain output slowly decreased, the patient's endotracheal tube was removed, and temperature and WBC count returned to normal. On postoperative day 47 a CT scan performed because of recurrent fever demonstrated persistent periaortic fluid collection. A sinogram of the perigraft abscess performed the same day showed contrast outlining both limbs of the graft in the abdomen and extending into the pelvis (Fig. 2). The 14 F drain was replaced with a 12 F straight catheter and a 16 F van Sonnenberg drainage catheter. A sinogram through the splenic bed drain showed continuity with a nonobstructed pancreatic duct (Fig. 3). Although no contrast communication could be shown between the drain in the splenic bed and the perigraft region, the fluid from the perigraft drain had amylase values as high as 3800 IU/L. A CT scan on postoperative day 50 showed decreased perigraft fluid collection. Over the next week the splenic bed drain was upsized to 16 F and the 12 F perigraft drain was upsized to 16 F. Intensive daily catheter irrigation with normal saline solution was continued by the interventional radiology staff in addition to the catheter irrigation performed by the nursing staff every 8 hours. Irrigation resulted in return of pus and necrotic tissue from all drain sites. On postoperative day 76 amoxicillin/clavulanic acid, 500 mg by mouth three times a day, was instituted for chronic bacterial suppression. The amylase level of the splenic bed drain had fallen from 27,900 IU/dl on postoperative day 48 to 191 IU/dl on postoperative day 85. A sinogram on postoperative day 97 revealed no residual splenic bed abscess cavity but did show persistent communication with a nondilated pancreatic duct. The splenic bed drain was removed without incident over the following 2 days and the fistula tract

Fig. 1. CT scan through the lower abdomen shows a large area of fluid collection surrounding both limbs of the graft and the aneurysm sac.

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488 Casereports

closed. A C T scan on postoperative day 99 revealed minimal perigraft fluid. Drain output continued to decrease, and by postoperative day 113 output was less than 10 ml/24 hr and the perigraft drains were removed. All wounds were healed and the patient was transferred to a multispecialty inpatient rehabilitation program. The patient was discharged home on postoperative day 162 on a regimen of chronic suppressive oral antibiotics. Three and a half years after the operation, the patient shows no clinical evidence of infec-

Fig. 2. Sinogram demonstrating the aortobi-iliac graft (arrowheads) as a filling defect within the abscess cavity.

tion. Evaluation with CT scans and indium 11 l-labeled white blood cell scans, erythrocyte sedimentation rates, and WBC counts have revealed no evidence of infection.

DISCUSSION Aortic graft infection is life-threatening and is associated w i t h significant m o r b i d i t y from limb l o s s ) 6 Graft infection m a y present w i t h overw h e l m i n g sepsis or in a m o r e indolent fashion. The latter p r e s e n t a t i o n is m o s t c o m m o n l y associated w i t h late infection w i t h Staphylococcus epidermidis. 2° The s t a n d a r d t r e a t m e n t for infected a b d o m i n a l aortic grafts is e x t r a - a n a t o m i c bypass w i t h excision of the infected graft a n d d e b r i d e m e n t of adjacent infected t i s s u e ) 6 Localized infection of the femoral portion of a o r t o f e m o r a l grafts has also b e e n treated w i t h rotational muscle flap p r o c e d u r e s 2~ a n d c o n t i n u o u s povidone-iodine irrigation. 22 Neither m e t h o d has routinely b e e n used to treat a n infected aortic s e g m e n t of a n aortofemoral graft. Successful p e r c u t a n e o u s catheter m a n a g e m e n t of infected fluid collections surr o u n d i n g synthetic arterial grafts has b e e n reported. 17-~9 M a t l e y et al. ~8 a n d Tobin ~9 each used only p e r c u t a n e o u s drainage a n d antibiotics to treat one case of graft infection. Lambiase et a l Y used p e r c u t a n e o u s c a t h e t e r drainage to stabilize four acutely ill high-risk surgical patients to the e x t e n t t h a t m o r e definitive surgical t r e a t m e n t could be u n d e r t a k e n in three. Morris et al. 23 reported achieving a cure in 8 of I0 high-risk patients w i t h aortic graft infection treated by leaving the infected graft in place, surgically de-

Fig. 3. Sinogram demonstrating fluid collection in the splenic bed communicating with the pancreatic duct and drainage into the duodenum.

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briding adjacent infected tissue, placing drains operatively, and then using transcatheter antibiotic irrigation as well as systemic antibiotics. Although this technique, as compared to the percutaneous technique we describe, subjects the patient to reoperation, it allows prompt and more complete removal of infected tissue and visualization of anastomoses. With percutaneous drainage it is not possible to directly evaluate arterial integrity and possible impending suture line failure. The role of local transcatheter antibiotics remains to be determined. It is unclear whether the excellent results achieved by Morris et al. 23 are attributable to their aggressive local antibiotic regimen or to the drainage and debridement portion of their technique, which allows juxtaposition of prosthetic material with viable host tissue. The case reported herein demonstrates successful management of an acutely infected aortobi-iliac graft with concomitant intraabdominal abscess and pancreatic fistulas, all treated with percutaneous catheter drainage. This least invasive method was chosen because the patient was a poor surgical candidate as a result of other vascular disease, sepsis, pulmonary compromise, and lack of a suitable noninfected field through which to perform extra-anatomic bypass. Irrigation by interventional radiologists allowed immediate assessment of the adequacy of drainage. If all irrigation fluid was not able to be aspirated, additional drains were placed, drains were repositioned, or larger drains were placed depending on CT and sinogram findings. The combination of infection and pancreatic fluid around the graft was thought to place the patient at great risk of anastomotic dehiscence; therefore we made every effort to optimize drainage. We attribute our success in this case to the use of culture-specific systemic antibiotics and aggressive tube management and saline solution irrigation as well as frequent sinograms and CT scans to assess catheter position and adequacy of drainage.

CONCLUSION Percutaneous catheter drainage of acute graft infection can be considered in high-risk patients when acceptable surgical options do not exist. Aggressive catheter management with percutaneous drainage of concomitant intra-abdominal abscesses, control of fistulas, and frequent follow-up CT scans and sinograms to direct catheter management are essential. Large-bore catheters (16 F), frequent irrigation with saline solution, and culture-directed systemic antibiotic therapy are recommended.

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REFERENCES 1. O'Brien T, Collin J. Prosthetic vascular graft infection. Br J Surg 1992;79:1262-1267. 2. Liekweg WG, Greenfield LJ. Vascular prosthetic infections: Collected experience and results of treatment. Surgery 1977; 81:335-342. 3. O'Hara PJ, Hertzer NK Beven EG, et al, Surgical management of infected abdominal aortic grafts: Review of a 25-year experience. J Vasc Surg 1986;3:725-731, 4. Schmitt DD, Seabrook GR, Bandyk DF, et al. Graft excision and extra-anatomic revascularization: The treatment of choice for the septic aortic prosthesis. J Cardiovasc Surg 1990;31:327-332. 5, Szilagyi DE, Smith RE Elliott JP, et at. Infection in arterial reconstruction with synthetic grafts. Ann Surg 1972; 176:321 333. 6. Yeager RA, Moneta GL, Taylor LM Jr, et al. Improving survival and limb salvage in patients with aortic graft infection. Am J Surg 1990;159:466-469. 7. Mueller PE, van Sonnenberg E, Ferrucci JT Jr, Percutaneous drainage of 250 abdominal abscesses and fluid collections. Part II. Radiology 1984; 151:343-347. 8. Gerzof SG, Robbins AH, Birkett DH, et al. Percutaneous catheter drainage of abdominal abscesses guided by ultrasound and computed tomography. AJR 1979;133:1-8. 9. van Sonnenberg E, Mueller PR, Ferrucci JT Jr. Percutaneous drainage of 250 abdominal abscess and fluid collections. Part I. Radiology 1984;151:337-341. 10. Vogelzang RL, Limpert JD, Yao JST. Detection of prosthetic vascular complications: Comparison of CT and angiography. A JR 1987;148:819-823. 11. Qvarfordt PG, ReiIly LM, Mark AS, et al. Computerized tomographic assessment of graft incorporation after aortic reconstruction. Am J Surg 1985;150:227-231. 12. Low RN, Wail SD, Jeffrey RB, et al. Aortoenteric fistula and perigraft infection: Evaluation with CT. Radiology 1990;175: 157-162. 13. Katz BH, Black RA, Colley DP. CT-guided fine needle aspiration of a periaortic collection. J Vasc Surg 1987;5:762-764. 14. Cunat JS, Haaga JR, Rhodes R, et al. Periaortic fluid aspiration for recognition of infected graft: Preliminary report. AJR 1982;139:251-253. 15. Mark A, Moss AA, Lusby R, et al. CT evaluation of complications of abdominal aortic surgery. Radiology 1982;145:409414. 16. Mark AS, McCarthy SM, Moss AA, et al. Detection of abdominal aortic graft infection: Comparison of CT and In-labeled white blood cell scans. AJR t985;144:315-318. 17. Lambiase RE, Dorfman GS, Cronan JJ. Percutaneous management of abscesses that involve native arteries or synthetic arterial grafts. Radiology 1989;173:815-818. 18. Matley PJ, Beningfield SJ, Lourens S, et al. Successful treatment of infected thoracoabdominal aortic graft by percutaneous catheter drainage. J Vasc Surg 1991;13:513-515. 19. Tobin KD. Aortobifemoral perigraft abscess: Treatment by percutaneous catheter drainage. J Vasc Surg 1988;8:339-343. 20. Bandyk DE Berni GA, Thiele BL, et at. Aortofemorat graft infection due to Staphylococcus epidermidis. Arch Surg t984; 119:102-108. 21. Mixter RC, Tumipseed WD, Smith DJ Jr, et at. Rotational muscle flaps: A new technique for covering infected vascular grafts. J Vasc Surg 1989;9:472-478. 22. Kwaan JHM, Connolly JE. Successful m a n a g e m e n t of prosthetic graft infection with continuous povidone-iodine irrigation, Arch Surg 1981;116:716-720. 23. Morris GE, Friend PJ, Vassallo DJ, et al. Antibiotic irrigation and conservative surgery for major aortic graft infection. J Vasc Surg 1994;20:88-95,