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R L Dalman

Publications and source records attributed to R L Dalman.

35 records · Page 2Linked to original sources
PubMed1996

Is completion arteriography mandatory after reversed-vein bypass grafting?

Many surgeons advocate uniform performance of operative completion arteriography after leg bypass surgery to ensure technical success and to optimize short- and intermediate-term graft patency. To determine the impact of this practice on the outcome of reversed-vein bypass surgery and associated patient charges, we reviewed our series of consecutive nonemergent leg bypass procedures. Ninety-three infrainguinal bypass procedures were performed in 80 patients (76 men and 4 women) from September 1991 to August 1994. The patients' average age was 67 years (range, 30 to 92 years). Follow-up (mean, 113.1 months; range, 1 to 36 months) was available on 91 grafts (97%). Indications for surgery included limb salvage in 75 cases, claudication in 12 cases, and popliteal aneurysm exclusion in 6 cases. All patients survived surgery. Primary graft patency rates as determined by life-table analysis were 87%, 81%, 78%, and 78% at 6 months and at 1, 2, and 3 years, respectively. Limb-salvage rates were 95%, 91%, 87% and 87% at the same intervals. Bypass procedures were divided into two groups. The 25 grafts in group 1 were evaluated with inspection, continuous-wave Doppler insonation, and routine completion arteriography. The 68 grafts in group 2 were evaluated by inspection and insonation alone. Fourteen grafts occluded after surgery (average, 5 months; range, 1 to 12 months), five in group 1 and nine in group 2. The likelihood of graft occlusion was similar in both groups (p = 0.42). The optimal method of confirming technical adequacy after bypass surgery in the clinically satisfactory graft remains uncertain. Charges for completion arteriography at our institution average $700, including 15 minutes of additional operative time. In our experience, these charges do not appear to be justified by improved short- or intermediate-term graft patency rates in reversed-vein grafts when completion arteriography is performed.

Adult↗
PubMed1995

Oxygen saturation of blood in the superior mesenteric vein: in vivo verification of MR imaging measurements in a canine model. Work in progress.

PURPOSE: To evaluate the accuracy of magnetic resonance (MR) imaging in estimating oxygen saturation of blood (%HbO2) in the superior mesenteric vein (SMV) of a canine model in vivo. MATERIALS AND METHODS: MR imaging was used to measure the T2 of blood in samples obtained via a catheter placed in the SMV in seven mongrel dogs. %HbO2 was measured with a reflectance oximeter. These measurements were obtained at the resting state, during superior mesenteric artery occlusion, and after reperfusion. MR imaging and oximeter measurements were then compared by using linear regression analysis. RESULTS: Refocusing intervals (tau 180) of 12 and 24 msec were used for 17 and 18 %HbO2 measurements with MR imaging, respectively. With tau 180 of 12 msec, there was an excellent correlation between MR imaging measurements and oximeter measurements (r = .969). The intercept was 5.3% and the slope was 0.959. With tau 180 of 24 msec, r = .953, the intercept was 15.4%, and the slope was 0.817. CONCLUSION: Estimates of %HbO2 in the SMV with MR imaging are accurate in the range of most clinical interest.

Animals↗
PubMed1995

Simultaneous measurement of flow in the superior mesenteric vein and artery with cine phase-contrast MR imaging: value in diagnosis of chronic mesenteric ischemia. Work in progress.

PURPOSE: To evaluate the use of measurements of blood flow in the superior mesenteric vein (SMV) and superior mesenteric artery (SMA) simultaneously acquired with phase-contrast cine magnetic resonance (MR) imaging for diagnosing chronic mesenteric ischemia. MATERIALS AND METHODS: Simultaneous measurements of flow in the SMV and SMA were obtained in six healthy volunteers and eight patients with angiographically proved SMA stenosis (six asymptomatic, two symptomatic). Flow dynamics in both vessels were correlated with the degree of arterial disease seen at angiography and with the presence or absence of ischemic symptoms. RESULTS: Postprandial SMV and SMA flow increased substantially less in patients with atherosclerosis than in volunteers. Comparison of simultaneous SMV and SMA flow measurements provided more information about collateral flow to and from the mesenteric circulation than did either the SMV or SMA flow measurement alone. CONCLUSION: Simultaneous SMV and SMA flow measurement with cine phase-contrast MR imaging may be useful in diagnosing and understanding chronic mesenteric ischemia.

Adult↗
PubMed1994

Antiphospholipid antibodies in vascular surgery patients. A cross-sectional study.

BACKGROUND: Autoantibodies to phospholipid (aPL) have been associated with vascular thromboses in cerebral, coronary, and peripheral venous and arterial sites. To date, no large cross-sectional study has examined the incidence of occurrence of aPL in patients with peripheral arterial disease. METHODS: A cross-sectional study was performed with patients admitted for vascular surgery procedures to treat peripheral arterial disease for 23 months between January 1, 1990 and November 1, 1991. Consecutive patients were evaluated for the presence of aPL. Medical records for each patient were reviewed in detail, and historic, operative, and postoperative parameters were tabulated for relationship to the presence of aPL. RESULTS: Two hundred thirty-four patients underwent complete testing for aPL. All patients were receiving chronic aspirin therapy. This represented 86% of admissions. Antiphospholipid antibodies were detected in 60 patients (26%). No differences in age, sex, operation performed, or postoperative outcome were found between patients with and without aPL. However, patients with aPL were 1.8 times more likely to have undergone previous lower extremity (LE) vascular surgery than patients without aPL (95% confidence interval = 1.0 - 3.6, p = 0.047). Patients with aPL and previous LE vascular surgery were 5.6 times more likely to have had occlusion of that procedure than patients without aPL (95% confidence interval = 1.9 - 16.8, p = 0.03). The occluded previous LE procedures had a shorter duration of patency before occlusion in patients with aPL than in those without (mean duration of patency 17 months vs. 50 months, p < 0.003). Patients with occluded previous LE procedures and aPL were 4 times more likely to be female (95% C.I. = 1.4 - 11.3, p = 0.018). CONCLUSIONS: The incidence of aPL in vascular surgery patients is substantial. Vascular surgery patients with aPL are more likely to have failure of previous LE bypass procedures and to be female and the bypass failure occurs significantly more rapidly than in patients without aPL. Based on these data, testing of vascular surgery patients for aPL and investigation of alternative antithrombotic treatment regimens in patients with aPL appears warranted.

Aged↗
PubMed1994

Chronic mesenteric ischemia: evaluation with phase-contrast cine MR imaging.

PURPOSE: To compare superior mesenteric artery (SMA) blood flow in healthy volunteers and patients with stenoses in the fasting state and after food intake by using phase-contrast (PC) cine magnetic resonance (MR) imaging. MATERIALS AND METHODS: Ten healthy subjects, four asymptomatic patients (three with 50% stenosis, one with 70% stenosis), and one symptomatic patient (with 80% stenosis) were studied. All subjects were studied after fasting at least 8 hours and 15, 30, and 45 minutes after ingesting a standard meal. RESULTS: In healthy volunteers, SMA blood flow at all postprandial intervals increased significantly compared with that obtained after fasting (P < or = .0005). The percentage change in SMA blood flow 30 minutes after food intake provided the best distinction between the healthy subjects, the asymptomatic patients, and the symptomatic patient. CONCLUSION: Cine PC MR imaging is an effective, noninvasive technique for measuring SMA blood flow.

Adult↗
PubMed1993

Viability and biodistribution of 68Ga MPO-labelled human platelets.

The viability and biodistribution of 68Ga-mercaptopyridine-N-oxide (MPO)-labelled autologous platelets was studied in 10 patients. The average platelet labelling yield was 36 +/- 12% and injected activity was 2.0 +/- 0.9 mCi 68Ga. The % activity in platelets per ml whole blood was 64 +/- 20% at 15 min-1.0 h postinjection and 76 +/- 14% at 2-4h. The average recovery of platelets (% injected platelets circulating in peripheral blood) was 31 +/- 21% at 15 min-1 h and 39 +/- 20% at 2-4 h. The positron emission tomographic (PET) images showed high circulating vascular background. Two patients had technically inadequate scans, and six were false negative due to high blood background. One patient with a massive pulmonary embolus occurring 24 h prior to scanning had marked uptake of 68Ga platelets in a large clot in the superior branch of the right main pulmonary artery. A second patient, with 68Ga platelets circulating during angioplasty of a left posterior tibial artery stenosis, had intense uptake in the lesion shown on the PET scan obtained 4 h following the procedure. These results indicate good viability of 68Ga-MPO-labelled autologous human platelets, but poor visualization of clots by PET imaging, due to the high blood background at early times.

Blood Platelets↗
PubMed1992

Upper extremity arterial bypass distal to the wrist.

Seventeen arterial bypass procedures distal to the wrist have been performed in 13 men and two women at the Oregon Health Sciences University during the past 9 years. Ten patients had traumatic true or false aneurysms of the ulnar artery with digital embolization. Five patients with end-stage renal disease had severe hand and finger ischemia manifested by rest pain or digital ulceration resulting from widespread forearm and hand arterial occlusions. Patients with aneurysms of the ulnar artery underwent excision and reversed autogenous vein grafting (n = 11) from the distal ulnar artery in the forearm to the superficial palmar arch. All the patients with end-stage renal disease had severe occlusive disease of the forearm and hand arteries and underwent a variety of procedures including radial-radial bypass (n = 2), ulnar-ulnar bypass (n = 2), radial-radial bypass with takedown of a Brescia-Cimino fistula (n = 1), and brachial-radial bypass (n = 1). High-quality upper extremity and magnification hand arteriography was essential for operative planning and was available on all patients. Distal saphenous vein from the ankle or foot was the graft source in 16 procedures and basilic vein the source in one procedure. All operations were performed with headlight illumination, optical loupes, fine sutures, and microvascular instruments. There were no operative deaths or major complications. The mean follow-up period was 14 months. Of the 17 grafts, 16 remained patent by clinical and vascular lab criteria. The single occlusion occurred in an ulnar aneurysm bypass and was accompanied only by mild intolerance to cold.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Limb salvage vs amputation for critical ischemia. The role of vascular surgery.

Since 1980, 498 patients with 627 critically ischemic legs (rest pain, gangrene, ischemic ulcer, and ankle-brachial pressure index less than 0.40) were treated with revascularization regardless of operative risk or anticipated operative difficulty. Primary amputation was performed only when no graftable distal vessels were present (14 primary amputations [2.8%]) or in neurologically impaired, hopelessly nonambulatory patients. The mortality for revascularization was 2.3%, and the median hospital stay was 11 days. During follow-up, 41 limbs (7%) required amputation, 31 after failure of revascularization and 10 despite patent revascularizations. Renal failure had an adverse influence on limb salvage (67%) because of a significantly increased requirement for amputation despite patent revascularizations. We conclude aggressive limb revascularization in patients with critical lower-extremity ischemia results in low operative morbidity and mortality and excellent long-term limb salvage. Patients with critical leg ischemia and renal failure are at higher risk for limb loss than patients without renal failure.

Adult↗
PubMed1991

Simultaneous operative repair of multilevel lower extremity occlusive disease.

Sixty-two patients (39 men (63%), 23 women (27%), mean age 68 years) with multilevel lower extremity arterial occlusive disease underwent simultaneous inflow and outflow operative arterial repair consisting of aortofemoral bypass in 22 (35%), axillofemoral bypass in 17 (28%), femorofemoral bypass in 15 (24%), iliac endarterectomy in 7 (11%), and unilateral aortoiliac bypass in 1 (2%), combined with 69 outflow procedures (unilateral in 55 patients, 89%), including above-knee femoropopliteal in 12 (17%), below-knee femoropopliteal in 35 (51%), femoroinfrapopliteal in 20 (29%), popliteal tibial in 1 (1%), and femoropedal bypass in 1 (1%). Multiple criteria were used to identify patients with multilevel disease likely to benefit from multilevel procedures. The operations were performed by two operating teams in a median time of 240 minutes. Prosthetic grafts were used for eight (13%) distal bypasses, the remainder were autogenous vein. There was one operative death (1.8%). The mortality rate, morbidity rate, and operative time were not significantly different from a group of patients who underwent concurrent, isolated inflow operations (aortofemoral, axillobifemoral, femorofemoral bypass or iliac endarterectomy). Mean follow-up was 14.9 months (range, 0 to 120). The life-table primary patency for the inflow procedures was 92.6% at 24 months, the outflow was 94.9% at 24 months. Cumulative limb salvage was 90.9% at 48-month follow-up. All patients with claudication were relieved of their symptoms. We conclude that complete correction of multilevel disease can be accomplished with operative time, morbidity rate, and patency equal to that of single level repair. Multilevel procedures provide complete relief of symptoms in a higher percentage of patients than has been reported after single level repair.

Adult↗
PubMedDate not supplied

Spontaneous late carotid-cutaneous fistula following radical neck dissection: a case report.

The authors present an unusual case of a spontaneous carotid-cutaneous fistula occurring as a late complication 4 years after radical neck dissection and postoperative radiation therapy for tonsillar squamous cell carcinoma in a 50-year-old patient. The etiologic factors predisposing patients to carotid artery rupture following radical neck dissection and a surgical option for carotid artery reconstruction instead of ligation are discussed.

Carcinoma, Squamous Cell↗