Biomedical subjects

M J Dougherty

Publications and source records attributed to M J Dougherty.

At least 37 records · Page 2Linked to original sources

PubMed1998

Revision of failing lower extremity bypass grafts.

BACKGROUND: Color-duplex ultrasound (CDU) surveillance of arterial bypass grafts has been validated, but the natural history of "failing" grafts remains poorly defined. Our purpose was to compare failing grafts having prophylactic revision with those that did not. METHODS: Postoperative duplex surveillance was performed in an accredited vascular laboratory for all lower extremity bypass grafts performed at a single institution. Eighty-five infrainguinal grafts (57 vein, 21 polytetrafluoroethylene (PTFE), and 7 composite grafts) in 83 patients were identified as failing by accepted criteria. Twenty-five grafts were revised early (early), 20 grafts revised more than 2 months after the initial CDU-abnormality (late), and 40 grafts were not prophylactically revised (no revision) at any time. RESULTS: The three groups were not different (P > 0.10) with regard to gender, age, level of bypass, type of conduit, location of stenoses, or timing of abnormality after surgery. No revision patients more frequently had diffuse low peak systolic flow velocity (PSV) as the CDU abnormality (P = 0.013). Cumulative primary patency was significantly better at 12 months (P = 0.028) in the no revision group (78.9%) compared with early grafts (43.1%) or late grafts (63.8%), and this difference remained significant when low PSV grafts were excluded from analysis. However, assisted primary patency, secondary patency, and limb salvage rates did not differ between the three groups (P > 0.10). CONCLUSIONS: Our experience in this retrospective study contradicts other reports supporting the efficacy of prophylactic graft revision for grafts identified as failing by currently accepted CDU criteria. Refinement of CDU criteria to more accurately predict graft thrombosis is needed.

Adult↗

PubMed1998

Selective use of duplex ultrasound to replace preoperative arteriography for failing arterial vein grafts.

PURPOSE: In an effort to minimize costs and patient discomfort, we determined whether duplex ultrasound (DU) could selectively replace preoperative arteriography performed in the radiology suite to diagnose failing arterial bypass grafts (FABs) constructed of autogenous vein. METHODS: Between January 1, 1994, and December 31, 1996, we treated 106 FABs. Graft revision solely on the basis of DU was performed only if a focal stenosis was clearly identified in the graft (peak systolic velocity [PSV] > 300 cm/sec, ratio of adjacent PSVs > 3.0) or in inflow or outflow arteries (resulting in uniform graft PSVs < 45 cm/sec). Intraoperative arteriograms were frequently obtained to confirm DU findings. Preoperative arteriograms were obtained if DU revealed multiple or ill-defined stenoses, diffuse inflow or outflow arterial disease, uniformly low PSVs without an identifiable lesion, or equivocal stenosis despite clinical evidence of an FAB. RESULTS: Seventy-three (69%) FABs with 81 lesions were revised on the basis of DU only. Of 76 stenotic lesions, an intraoperative arteriogram or surgical findings confirmed a diameter stenosis of 75% to 99% in 69 grafts (91%) and stenosis of 50% to 74% in three grafts (4%). DU incorrectly identified the site of stenosis or underdiagnosed the extent of disease in four grafts (5%). DU correctly identified the site of missed arteriovenous fistulas in five grafts. The 73 FABs were treated with intraoperative balloon angioplasty (30 grafts), patch angioplasty (20), interposition or jump grafts (12), ligation of arteriovenous fistula (3), a new bypass graft (1), or a combination of these interventions (7). A significant change in intraoperative strategy potentially could have been avoided if a preoperative arteriogram had been obtained in three of the 73 FABs (4.1%). CONCLUSIONS: DU can reliably be used to revise FABs and avoid the morbidity, discomfort, and cost of confirmatory arteriography in two thirds of cases.

Adult↗

PubMed1997

Use of arm and lesser saphenous vein compared with prosthetic grafts for infrapopliteal arterial bypass: are they worth the effort?

PURPOSE: Arm and lesser saphenous veins (ALSVs) are generally considered to be the best alternative for infrapopliteal arterial bypass grafts when greater saphenous vein is not available. The need for additional incisions and repositioning of the patient, along with occasional use of general anesthesia for arm vein harvesting, led to our perception that the use of ALSVs increased operative time and possibly patient discomfort. Therefore, we compared the outcome of ALSVs with that of prosthetic infrapopliteal arterial bypass procedures performed at our hospital. METHODS: Between July 1, 1991, and Dec. 31, 1996, we performed 96 infrapopliteal arterial bypass procedures using 45 ALSVs (28 arm vein, 17 lesser saphenous) and 51 polytetrafluoroethylene (PTFE) grafts. Seventy grafts were single-length ALSV or PTFE bypass grafts, and 26 grafts were placed as the distal segment of a sequential or composite bypass graft. Every attempt was made to use ALSV and avoid the use of PTFE, even if a short segment of the vein graft measured less than 4.0 mm in diameter. There were no significant differences between patients with ALSV compared with PTFE grafts in terms of age, sex, indication for surgery, or number of previous revascularization procedures (2.1 vs 1.7), respectively (p > 0.05). However, ALSV grafts had more factors associated with an expected worse outcome: they were more commonly anastomosed to pedal arteries (17% [8 of 45] vs 0%; p = 0.0009), less commonly single-segment grafts (62% [28 of 45] vs 82% [42 of 51]; p = 0.03), had higher average runoff resistance values (2.3 vs 1.5; p = 0.001), and were less frequently treated with lifelong warfarin (65% [29 of 45] vs 95% [48 of 51]; p = 0.0001). RESULTS: The hospital mortality rate was 3.1% (3 of 96; 3 PTFE). All deaths were cardiac-related. Despite the potential factors associated with worse patency rates for ALSVs, 2-year assisted primary patency rates tended to be higher for arm veins (46%) than for lesser saphenous veins (23%) and PTFE grafts (26%), although this difference was not statistically significant. Limb salvage rates were similar between ALSV and PTFE grafts (76% vs 71%, respectively). The average operative time was significantly longer for ALSV bypass procedures (mean, 6.2 hours) than for PTFE bypass procedures (mean, 4.9 hours; p = 0.003), and for single-length conduits when revision of previously placed grafts was not attempted, the operative time was 4.0 hours for ALSV grafts and 2.5 hours for PTFE grafts. CONCLUSION: In our experience ALSV bypass grafts to infrapopliteal arteries do not function as well as reported by some others. In spite of the extra effort involved, arm vein grafts are preferred over PTFE grafts for their likely higher assisted primary patency rates and equivalent, if not better, limb salvage rates.

Aged↗

PubMed1997

Same-day admissions and other cost-saving strategies for elective aortoiliac surgery.

PURPOSE: We retrospectively analyzed whether same-day admissions and other resource utilization methods for patients undergoing elective infrarenal aortoiliac surgery (AoIS) were safe and cost-effective. METHODS: Morbidity and mortality rates and costs were compared between 71 patients admitted before the day of surgery (group I) and 57 patients admitted the day of surgery (group II) who underwent elective AoIS between July 1, 1992, and December 31, 1995. After January 1, 1994, a concerted effort was made to decrease hospital costs by performing out-patient preoperative assessment, admitting patients the morning of surgery, and planning early discharge through implementation of clinical pathways. Patients were excluded (total, 33; 20%) from analysis if they were admitted before the day of surgery for intravenous hydration (5), optimizing cardiac function (4), or prolonged preoperative antibiotics (2), or if they required emergency surgery (10) or were transferred from another service or hospital (12). After exclusion, there were no significant differences (p > 0.05) between groups I and II in terms of age, sex, race, diabetes, hypertension, pulmonary disease, cardiac disease, renal insufficiency, type of incision (midline or retroperitoneal), indication for surgery (aneurysm or occlusive disease), or inflow site (aorta or common iliac artery). RESULTS: There were no significant differences between groups I and II in terms of mortality rate (0%); cardiac (1.4% [1/71] vs 0%), pulmonary (9.9% [7/71] vs 5.3% [3/57]), or renal (1.4% [1/71] vs 0%) complications; or readmission rates within 30 days (5.6% [4/71] vs 5.2% [3/57]), respectively (p > 0.05). There were significant decreases in length of hospital stay (mean, 6.4 vs 11.2 days; p < 0.0001) and hospital cost per patient ($34,198 vs $45,694; p = 0.001) for group II compared to group I, respectively. CONCLUSIONS: The majority of patients who require elective infrarenal aortoiliac surgery can be admitted the day of surgery and undergo early discharge with significant hospital cost savings and without apparent increase in morbidity or mortality rates.

Adult↗

PubMed1997

Are Bacteria Omnipresent on Phanerochaete chrysosporium Burdsall?

Cultures of Phanerochaete chrysosporium were examined for the presence of bacteria as previously described (F. Seigle-Murandi, P. Guiraud, C. Falsen, and K.-E. Eriksson, Appl. Environ. Microbiol. 62:2477-2481, 1996). Under no conditions could bacteria be isolated from cultures of P. chrysosporium. With PCR primers corresponding to small-subunit rRNA genes, no bacterium-like product could be amplified from cultures of the widely used P. chrysosporium strain BKM-F-1767. Thus, we could find no evidence of bacteria in association with P. chrysosporium BKM-F-1767.

Journal Article↗

PubMed1996

Safety and cost-efficiency of 24-hour hospitalization for carotid endarterectomy.

The safety and cost savings of carotid endarterectomy (CEA) were determined with guidelines developed after vascular "critical pathways" were implemented. Using these guidelines, our goal was to admit patients the day of surgery and to discharge them the next morning. Morbidity, mortality, readmission rates, same-day admissions, duration of stay, and hospital costs were compared between patients undergoing CEA who were electively admitted between September 1, 1992 and August 31, 1993 (group 1) and January 1, 1994 and March 31, 1995 (group 2). Between these two time periods, vascular critical pathways were instituted and all preoperative examinations were performed on an outpatient basis. The majority of CEAs were performed with the patient under general anesthesia. We found no significant differences between group 2 (n = 68) vs. group 1 (n = 40) in terms of mortality (1.5% [1 of 68] vs. 2.5% [1 of 40]), cardiac events (2.9% [2 of 68] vs. 2.5% [1 of 40]), neurologic events (2.9% [2 of 68] vs. 2.5% [1 of 40]), or readmission rate (1.5% [1 of 68] vs. 0% [0 of 40]). Same-day admissions were significantly higher (94% [64 of 68] vs. 5% [2 of 40]; p < 0.0001), and average duration of stay was significantly lower (1.3 vs. 5.1 days; p < 0.0001) in group 2 vs. group 1, respectively. Hospital charges were decreased by $5510 per patient in group 2. We conclude that hospital costs can be significantly reduced for most patients undergoing CEA when they are admitted on the day of surgery and discharged the following morning, with no negative impact on morbidity and mortality.

Aged↗

PubMed1996

Management and outcome of infrapopliteal arterial graft infections with distal graft involvement.

PURPOSE: The purpose of this study was to determine the outcome of patients with infrapopliteal artery graft infections (InfraPopGIs) who presented with graft infection distal to the popliteal artery. PATIENTS AND METHODS: Between July 1, 1979 and June 30, 1994, 27 patients presented with infrapopliteal artery graft infections (18 polytetrafluoroethylene [PTFE], 9 autologous vein). The infection involved the anastomosis in 22 cases (8 anterior tibial, 8 posterior tibial, 4 peroneal, 2 dorsalis pedis arteries) and was localized to the body of the graft in 5 cases (4 calf, 1 ankle). All bypasses were originally performed for limb salvage. Twelve patients with patent grafts and intact anastomoses were managed by complete graft preservation. Fifteen patients presented with occluded grafts (10), anastomotic hemorrhage (4), or systemic sepsis (1) and were treated by total or subtotal graft excision. RESULTS: The hospital mortality rate was 19% (5 of 27) and the amputation rate in survivors was 27% (6 of 22). These results were compared with a mortality rate of 13% (15 of 114; P > 0.05) and a limb loss rate of 10% (10 of 99)(P = 0.05) in 114 patients during this period who presented with infection proximal to the tibial arteries. Of 6 survivors with graft infections who required amputations, 5 lacked a suitable outflow artery for a secondary bypass and 1 developed progressive gangrene despite a patent secondary bypass. Among the other 16 survivors, 7 (44%) limbs remained viable without requiring a secondary bypass, 6 (37%) limbs were salvaged with successful preservation of patent grafts, and 3 (19%) required secondary bypasses to prevent limb loss. CONCLUSIONS: Patients presenting with infrapopliteal artery graft infections have higher amputation rates than patients with more proximal infected peripheral grafts. Selective graft preservation and selective revascularization when outflow arteries are available are essential adjuncts to minimize high rates of limb loss associated in patients with graft infections.

Amputation, Surgical↗

PubMed1996

Duplex ultrasonography to diagnose failing arterial prosthetic grafts.

BACKGROUND: Although several reports have documented the usefulness of a surveillance program with duplex ultrasonography (DU) to diagnose failing autologous vein bypasses, the effectiveness of DU to detect failing arterial prosthetic grafts has not been confirmed. We attempted to determine whether our program, which included DU and other noninvasive techniques (NonDU), was useful for this purpose. METHODS: Between July 1, 1991, and September 30, 1994, 85 prosthetic bypasses in 59 patients performed for lower extremity ischemia were entered into a graft surveillance protocol. There were 35 femoropopliteal, 16 femorotibial, 15 iliofemoral, 13 axillofemoral, and 6 femorofemoral bypasses. Both DU and NonDU were performed 1 week and every 3 months after the initial bypass or after graft revision. NonDU criteria of a failing graft included changes in symptoms or pulses, decreased ankle/brachial index greater than 0.15, or diminution of ankle pulse volume recordings greater than 50%. Normal grafts were bypasses that had less than 50% stenosis documented by arteriography or remained patent. Problem grafts were those that required revision or thrombosed before intervention. Follow-up of patient grafts ranged between 3 and 36 months (mean, 11 months). RESULTS: DU predicted 17 (81%) of 21 problem grafts versus only 5 (24%) diagnosed by NonDU (p = 0.001). Lesions associated with these 21 grafts were perianastomotic in 10 cases, in adjacent inflow or outflow arteries in 8 cases, and intrinsic to the graft in 3 cases. The likelihood of a graft thrombosing in the presence of a normal test was 7% (4 of 58) for DU compared with 21% (16 of 76) for NonDU (p = 0.04). CONCLUSIONS: DU is more sensitive than NonDU in predicting failure of prosthetic grafts. This study suggests that DU should routinely be performed as part of a surveillance program for peripheral arterial prosthetic bypasses.

Aged↗

PubMed1996

Congenitally absent inferior vena cava presenting in adulthood with venous stasis and ulceration: a surgically treated case.

Absence of the inferior vena cava (IVC) is an uncommon congenital abnormality. Symptoms of lower extremity venous insufficiency resulting from this anatomic abnormality have been reported only once in the English literature, and no experience with surgical treatment of this condition has been published. We report the case of an otherwise healthy 41-year-old man with an 18-month history of severe venous insufficiency involving the right leg manifested by extensive ulceration that did not respond to aggressive conservative treatment. Duplex findings were not suggestive of venous obstruction or reflux, but venography documented no filling of the common iliac vein or inferior vena cava, and outflow was via collaterals to the azygous and hemiazygous systems. Computed tomography demonstrated complete absence of the inferior vena cava with azygous continuation. A prosthetic bypass from the external iliac to the intrathoracic azygous vein was performed with complete symptomatic relief after a 30-month follow-up period. Venous bypass surgery may play a role in treatment of this rare cause of venous insufficiency.

Adult↗

PubMed1996

Thrombolytic and endovascular treatment of peripartum iliac vein thrombosis: a case report.

This case report details the multidisciplinary treatment of peripartum left iliac vein thrombosis using percutaneous catheter-directed urokinase thrombolysis and balloon thromboplasty. Enhanced chances for long-term patency and the normalization of venous function make these minimally invasive procedures accepted options for the treatment of iliofemoral deep venous thrombosis in selected peripartum patients.

Adult↗

PubMed1996

Role of nursing personnel in implementing clinical pathways and decreasing hospital costs for major vascular surgery.

Collaboration with key nursing personnel is essential to successfully implement clinical pathways, establish a dedicated vascular wing, and achieve significant hospital cost savings while still maintaining quality care with low morbidity and mortality rates. Key nursing personnel met once a month during a 1-year period with vascular surgeons, hospital administrators, and health care advisors to plan strategies to develop clinical pathways and establish a dedicated vascular ward. The pathways were then implemented. We compared morbidity, mortality, readmission rates, adn hospital costs among two groups of patients admitted for major vascular surgery. Nursing personnel, attending staff, and surgical residents found that treating patients who had undergone major vascular surgery was more straightforward and efficient after clinical pathways and a dedicated vascular wing were established. In addition, there were no significant differences between the groups in terms of overall mortality or pulmonary, neurologic, or cardiac complications despite shorter hospital stay and decreased hospital costs. Also there were no significant differences in readmission rates within 30 days.

Aged↗

PubMed1996

Comparison of the sex-pheromone components of Lutzomyia longipalpis (Diptera:Psychodidae) from areas of visceral and atypical cutaneous leishmaniasis in Honduras and Cost Rica.

The terpene components of extracts prepared from male Lutzomyia longipalpis (Diptera: Psychodidae) collected from four sites in Honduras and one in Costa Rica were analysed by high-performance liquid chromatography, gas chromatography and coupled gas chromatography--mass spectrometry. The terpene components of Lu. longipalpis from other regions of South America have previously been shown to be sex pheromones. The flies from the four areas of Honduras, where Leishmania chagasi infection may lead to visceral or atypical cutaneous leishmaniasis, were found to be homogenous, all producing 9-methylgermacrene-B. Three types of terpene (9-methylgermacrene-B, a novel homosesquiterpene and a small amount of diterpene) were detected in pools of flies from Liberia, Costa Rica, where only atypical cutaneous leishmaniasis has been found. These results indicate that there are probably at least two and possibly three distinct populations of Lu. longipalpis in this region. The clinical manifestation of Leishmania chagasi infection does not appear to be dependent on which population of Lu. longipalpis transmitted the parasite.

Animals↗

PubMed1996

Evaluation of an extended blood culture protocol to isolate fastidious organisms from patients with AIDS.

Recent reports of fastidious pathogens suggest the need for special blood cultures for immunocompromised patients. Blood cultures from 45 human immunodeficiency virus (HIV)-infected patients with unexplained fever (> or = 38.0 degrees C) and CD4 counts of < 125 cells per mm3 were collected into a vacuum tube with sodium polyanetholsulfonate, an Isolator tube, and BACTEC aerobic and anaerobic bottles. Blood from the sodium polyanethosulfonate tube was inoculated into BACTEC 13A bottles, which were read weekly for 16 weeks. Isolator sediment was divided among eight agar media, including four sheep blood agar media: chocolate agar, brain heart infusion blood agar, heart infusion blood agar, and brucella blood agar. Other agar plates included Sabouraud's, buffered charcoal-yeast extract, Middlebrook 7H11 (M7H11) with hemoglobin, and M7H11 with mycobactin J. Incubation conditions included air and CO2-enriched aerobic, microaerophilic, and anaerobic atmospheres. Aerobic BACTEC broths received an acridine orange stain on day 8 and were subcultured at 2, 4, and 8 weeks. Anaerobic BACTEC bottles were subcultured at 4 weeks. All solid media, including subcultures, were incubated for 8 weeks, providing a total of 16 weeks of incubation for each specimen. Clinically significant isolates included eight Mycobacterium avium complex isolates and one each of Bartonella henselae, Bartonella quintana, Shigella flexneri, Klebsiella oxytoca, and Cryptococcus neoformans. All isolates were detected with commercially available media and, with the exception of Bartonella spp., were recovered within incubation times routinely used in most clinical laboratories.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Bartonella (Rochalimaea) quintana bacteremia in inner-city patients with chronic alcoholism.

BACKGROUND: Bartonella (Rochalimaea) quintana is a fastidious gram-negative bacterium known to cause trench fever, cutaneous bacillary angiomatosis, and endocarditis. Between January and June 1993 in Seattle, we isolated B. quintana from 34 blood cultures obtained from 10 patients not known to be infected with the human immunodeficiency virus (HIV). METHODS: After identifying the isolates as B. quintana by direct immunofluorescence and DNA-hybridization studies, we determined strain hybridization with studies of restriction-fragment-length polymorphisms (RFLPs) of the intergenic spacer (noncoding) region of ribosomal DNA amplified by the polymerase chain reaction (PCR). To characterize the epidemiologic and clinical features of bartonella infections in these patients, we performed a retrospective case-control study using as controls 20 patients with blood cultures obtained at approximately the same time as those obtained from the index patients. RESULTS: B. quintana isolates from the 10 patients were indistinguishable by PCR-RFLP typing. All 10 patients had chronic alcoholism, and 8 were homeless (P = 0.001 for both comparisons with controls). The six patients who underwent HIV testing were seronegative. At the time of their initial presentation, seven patients had temperatures of at least 38.5 degrees C. Six patients had three or more blood cultures that were positive for B. quintana, and in four of these patients B. quintana was isolated from blood cultures obtained 10 or more days apart. Subacute endocarditis developed in two patients and required surgical removal of the infected aortic valve in one of them. Nine patients recovered; one died of sepsis from Streptococcus pneumoniae infection. CONCLUSIONS: B. quintana is a cause of fever, bacteremia, and endocarditis in HIV-seronegative, homeless, inner-city patients with chronic alcoholism.

Adult↗

PubMed1995

Renal endarterectomy vs. bypass for combined aortic and renal reconstruction: is there a difference in clinical outcome?

Are there differences in the patient characteristics and clinical outcome for transaortic renal endarterectomy vs. bypass grafting when either technique is combined with infrarenal aortic replacement for occlusive or aneurysmal disease? Two common perceptions persist: (1) combined aortic and renal procedures have a high risk and (2) bypass is easier and safer than endarterectomy. To address these controversies we compared 52 consecutive patients undergoing concomitant aortic and renal reconstruction between 1987 and 1991: 26 with bypass and 26 with endarterectomy. Bypass patients were older (70 vs. 64 years, p = 0.001), had more extensive plaque extending into the distal renal artery and more severe baseline azotemia (creatinine = 2.6 vs 1.7 mg/dl, p = 0.01), more clinically evident coronary heart disease (89% vs. 56%, p = 0.001), and a greater need for nephrectomy of a small nonfunctional pressor kidney (23% vs. 0%) than endarterectomy patients. In contrast, endarterectomy patients more commonly required aortic replacement for occlusive disease than for an aortic aneurysm (endarterectomy: 65% vs. 35%; bypass: 19% vs 81%, p = 0.002) and tended to require more intraoperative technical revisions (12% vs. 4%) than bypass patients. Both groups, however, experienced no operative mortality, had similar cardiorespiratory morbidity, and achieved equal improvement in hypertension (69% vs. 65%). Bypass patients, who already had more severe preoperative azotemia than endarterectomy patients, showed less improvement in the creatinine level (Cr = 2.1 vs. 1.4 mg/dl, p = 0.01) and had greater need for late dialysis (30% vs. 4%, p = 0.01). Only one patient on dialysis had graft occlusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1995

Thrombolysis to treat arterial thrombotic complications of heparin-induced thrombocytopenia.

An 80-year-old man with diabetes developed acute ischemia of the right leg secondary to heparin-induced thrombocytopenia while being treated for a pulmonary embolism. For fear of recurrent thrombosis at the operative site, he was treated with cessation of heparin, placement of a Greenfield filter, and intra-arterial infusion of urokinase into the popliteal artery for 36 hours. All arterial thrombus resolved with no complications. One week later he underwent a below-knee popliteal to anterior tibial artery translocated cephalic vein bypass and transmetatarsal amputation for progressive gangrene of the right toes. The graft remains patent 2 years later. This patient represents the eighth case reported in the world literature in which thrombolytic therapy was used to treat arterial thrombotic complications of heparin-induced thrombocytopenia. Five patients were successfully treated without complications, two others required major amputations, and one died of adrenal hemorrhage. Although thrombolytic therapy should be used cautiously for treatment of arterial thrombotic complications of heparin-induced thrombocytopenia, this adjunct may prove useful and safe in selected cases.

Aged↗

PubMed1995

Congenital aneurysm of the internal jugular vein in a pregnant woman.

A pregnant woman with a symptom-free congenital aneurysm of the internal jugular vein (IJV) is described. A color duplex scan revealed an aneurysm (2.4 cm in diameter) of the right IJV in the mid-neck without evidence of thrombus. To the authors' knowledge, this is the first reported case demonstrating that such a lesion in a pregnant woman can be safely managed without excision.

Adult↗

PubMed1995

Recommendations for initial antibiotic treatment of extracavitary arterial graft infections.

BACKGROUND: Initial antibiotic treatment of extracavitary arterial graft infections is usually empiric or based on Gram's stain findings. Increasing virulence of bacteria causing extracavitary arterial graft infections may render previous choices of antibiotics obsolete. The purposes of this study were to correlate Gram's stain findings of gram-positive bacteria and gram-negative bacteria with wound cultures and provide a microbiologic basis for appropriate initial antibiotic therapy. METHODS: Between July 1, 1979 and June 30, 1994, specimens obtained on the day of admission from purulent wounds involving 113 extracavitary arterial graft infections were retrospectively reviewed for Gram's stain and culture and sensitivity results. RESULTS: Gram's stain findings correlated with final cultures on only 28 of 113 cases (25%), including 20 of 48 pure gram-positive, 2 of 24 pure gram-negative, and 6 of 41 mixed bacterial cultures. Staphylococcus aureus was the most common gram-positive bacteria cultured (43 isolates) and Pseudomonas species was the most common gram-negative bacteria (25 isolates). Bacteria were sensitive to a first-generation cephalosporin in only 32% (36 of 113) of infections. A combination of vancomycin and either ticarcillin-clavulanic acid or ceftazidime, which have minimal toxicity and provide excellent coverage against staphylococci, Pseudomonas, and other gram-negative bacteria, would have covered 96% (109) and 95% (107) of cultured organisms, respectively. CONCLUSIONS: Regardless of Gram's stain findings, current recommendations for initial treatment of extracavitary arterial graft infections should include vancomycin and ceftazidime or ticarcillin-clavulanic acid until final culture and sensitivity results dictate the use of more selective antibiotics.

Anti-Bacterial Agents↗