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T C Bower

Publications and source records attributed to T C Bower.

At least 55 records · Page 3Linked to original sources

Mesenteric venous thrombosis: still a lethal disease in the 1990s.

PURPOSE: This study was designed to evaluate progress in diagnosis, management, and clinical outcome of mesenteric venous thrombosis (MVT). METHODS: We retrospectively reviewed the clinical course of 72 patients treated for mesenteric venous thrombosis between 1972 and 1993. RESULTS: Fifty-three patients had acute and 19 had chronic mesenteric venous thrombosis. Fifty-seven patients had secondary mesenteric venous thrombosis; previous abdominal surgical procedure and hypercoagulable states were the most prevalent associated conditions. Computed tomography was abnormal in all patients who underwent this test for acute mesenteric venous thrombosis and in 93% of those who had chronic disease. Angiography diagnosed acute mesenteric venous thrombosis in five (72%) of seven patients. Acute mesenteric venous thrombosis presented most frequently as abdominal pain (83%), anorexia (53%), and diarrhea (43%). Thirty-three (75%) had symptoms longer than 48 hours. Thirty-four (64%) patients with acute mesenteric venous thrombosis underwent a surgical procedure. Bowel resection was necessary in 31 patients. One patient had unsuccessful mesenteric venous thrombectomy. Seven patients with acute mesenteric venous thrombosis underwent anticoagulation without a surgical procedure, and 12 were observed. All patients with chronic mesenteric venous thrombosis were observed; nine of the 19 underwent anticoagulation. The median delay in diagnosis for patients with acute mesenteric venous thrombosis was 48 hours and did not decrease during the last decade. Mesenteric venous thrombosis recurred in 19 (36%) patients. The 30-day mortality was 27%. Long-term survival of patients with acute mesenteric venous thrombosis was significantly worse than that of those with chronic disease (36% vs 83% survival at 3 years). The patients with acute mesenteric venous thrombosis who underwent anticoagulation with and without surgical procedure had improved survival when compared with the observed group. CONCLUSION: Acute mesenteric venous thrombosis remains a lethal disease. Mortality has not improved in the last 22 years. Computed tomography is the most sensitive diagnostic test. Anticoagulation and surgical procedure enhanced survival in the acute subgroup. The underlying disease determined survival in chronic disease.

Acute Disease↗

Vena cava replacement for malignant disease: is there a role?

Resection and graft replacement of the vena cava for malignant disease is rarely performed, often because of the advanced tumor stage. Since August 1987 we have selectively performed caval replacement in conjunction with tumor resection in 11 patients. Three patients had superior vena cava reconstruction (SVCR) and eight had inferior vena cava replacement (IVCR). There were six males and five females whose mean age was 59.3 years (range 24 to 75 years). Two patients, each with superior vena cava obstruction, presented with symptoms from venous compression. Malignancies involving the superior vena cava were thyroid carcinoma in two patients and lymphoma in one. Cancers requiring IVCR were leiomyosarcoma in three patients, cholangiocarcinoma in two, and malignant fibrous histiocytoma, hepatocellular carcinoma, and colon carcinoma metastatic to the liver in one each. All IVCRs and two SVCRs were performed with expanded polytetrafluoroethylene grafts. The remaining SVCR was constructed with spiral saphenous vein. Six IVCRs involved replacement of the retrohepatic inferior vena cava in conjunction with major liver resection. Mean intraoperative blood transfusions were 5.3 units (range 0 to 10 units). There were no operative deaths. Complications occurred in four patients and included postoperative bleeding in two, myocardial infarction in one, and wound infection in one. There were no perioperative graft occlusions, but one patient developed graft occlusion 2 months after SVCR. All IVCR grafts have remained patent (mean follow-up of 8.8 months). Two patients with SVCRs have died from recurrent cancer at 3.2 and 3.4 years postoperatively. Six patients with IVCRs have developed tumor recurrence either locally (n = 1), at a distant site (n = 2), or both (n = 3). Importantly, eight of nine survivors have an excellent performance status. We conclude that vena cava reconstruction for malignancy can be performed safely, has few graft-related complications, and in some patients may offer the only possibility for tumor control.

Adult↗

Effects of cerebrospinal fluid drainage in patients undergoing thoracic and thoracoabdominal aortic surgery.

Cerebrospinal fluid (CSF) drainage has been reported to protect the spinal cord during surgical procedures requiring thoracic aortic cross-clamping. In 1986, CSF pressure monitoring and drainage was begun in an attempt to reduce the incidence of paraplegia associated with surgical repair of descending thoracic and thoracoabdominal aortic aneurysms (TAAA). These Group II patients (n = 50) were retrospectively compared to Group I patients (n = 49) who had undergone similar surgical procedures in the previous 3 years before CSF monitoring was introduced into this practice. Group II patients had intrathecal catheters placed for monitoring of CSF pressure and drainage of CSF to maintain the pressure < or = 15 mmHg. Seven patients (four in Group I, three in Group II) died before recovering from the anesthetic. Of the 47 patients in Group II who survived, none had clinically apparent complications such as an epidural hematoma or meningitis from the intrathecal catheter. The mean aortic cross-clamp time was 58.6 +/- 30.5 minutes (mean +/- SD) in Group I versus 65 +/- 42.6 minutes in Group II. Twenty-three patients in Group I and 16 patients in Group II had a shunt to the distal aorta. To maintain a CSF pressure of < or = 15 mmHg in Group II, an average of 46.9 +/- 6.9 mL of CSF was withdrawn. Of the 45 survivors in Group I, 4 developed a spinal cord deficit; the number of patients with spinal cord deficit in Group II was 4 out of the 47 who survived.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Variations of the arterial anatomy of the foot.

Reconstruction of the arteries of the foot in patients with severe chronic arterial occlusive disease has become a routine and valuable procedure. However, it is frequently difficult to select the optimal site for the distal arterial anastomosis. In order to determine the most important anatomic variations of foot arteries and the relationship of the dorsalis pedis artery to crossing tendons, the following study was performed in 30 cadaver limbs of 17 persons (9 men and 8 women). Their mean age at death was 69.8 years (range: 42 to 93 years). Methods to evaluate anatomy included anatomic dissection, arteriography, and preparation of corrosion cast models. The latter was performed by injection of liquid plastic and catalyst into the tibial arteries followed by chemical débridement of the soft tissue of the foot. Photographs of the corrosion cast models were taken at various stages of soft tissue dissolution. The dorsalis pedis artery was absent in 6.7% of the cases, and the arcuate artery was absent in 33%. The dorsalis pedis artery arose from the peroneal artery in 6.7%. The dorsalis pedis artery crossed under the extensor hallucis longus tendon at the ankle in 54%, above the ankle in 43%, but below the ankle in only 3%. Our study suggests that the optimal site for the dorsalis pedis artery anastomosis on the foot is the segment distal to the ankle.

Adult↗

Advanced carotid disease in patients requiring aortic reconstruction.

Perioperative stroke is a devastating complication of abdominal aortic operations. Patients requiring aortic reconstruction with advanced carotid occlusive disease pose a particularly challenging management problem regarding timing of operations. All patients (n = 121) undergoing both carotid artery endarterectomy (CEA) and abdominal aortic reconstruction (AAR) within 1 year of each other between 1979 and 1989 were reviewed. The sequence of operation was analyzed to determine its effect on early and late outcome. CEA was the first operation in 99 patients (group I); AAR was performed first in 22 patients (group II). Age, gender, number, types of risk factors, and associated medical problems were similar in both groups. Indications for CEA were: transient ischemic attacks (TIAs), recent ipsilateral stroke, or high-grade asymptomatic carotid artery stenosis exceeding 80%. Indications for aortic operation included: abdominal aortic aneurysm, aortoiliac occlusive disease, and combined aortic and renovascular disease. There were five perioperative strokes, two in group I (2%) and three in group II (14%) (p < 0.04). All strokes occurred after AAR. There were five perioperative deaths (4%), four in group I (4%) and one in group II (5%). Overall survival was significantly greater in group I compared to group II (p < 0.04); 5-year survival was 77% and 51%, respectively. Multivariate analysis demonstrated age, hypertension, and diabetes to adversely affect survival; CEA as the first procedure, however, had a protective effect. Importantly, eight strokes occurred in group I in late follow-up, but only one was ipsilateral to the CEA. We conclude that CEA in selected patients who require AAR is safe, and, when performed prior to abdominal aortic repair, reduces perioperative stroke and may improve long-term survival.

Adult↗

Myocardial revascularization before abdominal aortic aneurysmorrhaphy: effect of coronary angioplasty.

Percutaneous transluminal coronary angioplasty (PTCA) has assumed an increasing role in the preoperative preparation of patients with an abdominal aortic aneurysm (AAA). The influence of this modality on perioperative morbidity and long-term outcome has not been substantiated. To determine the effect of PTCA, we analyzed a cohort of 2,452 patients who underwent repair of an AAA between 1980 and 1990 at our institution. We compared the cardiac morbidity, mortality, and survival of patients who had preoperative coronary revascularization by PTCA or coronary artery bypass grafting (CABG). The overall perioperative mortality for the 2,452 patients was 2.9%. Preoperative coronary revascularization was necessary in 100 patients (4.1%)--86 had CABG and 14 had PTCA. Of these 100 patients, 95% had cardiac symptoms. Patients selected for PTCA, in comparison with CABG, had significantly less three-vessel disease but not significant differences in cardiac history or ejection fraction. During the study period, the use of PTCA increased significantly. The perioperative rate of myocardial infarction for patients with prior CABG was 5.8% in comparison with 0% for those with prior PTCA. No hospital deaths occurred in either group. The median interval between coronary revascularization and repair of an AAA was 10 days for PTCA and 68 days for CABG. The 3-year survival was not statistically different between CABG (82.8%) and PTCA (92.3%) groups. The rate of late cardiac events (at 3 years) was 56.5% in the PTCA group and 27.3% in the CABG group. We conclude that PTCA as part of a highly selective approach to coronary revascularization before repair of an AAA minimizes cardiac-related events and death.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Ischemic colitis.

Colon ischemia is a well-recognized clinical entity that often occurs spontaneously in patients over the age of 50 years. Many previous cases of nonspecific colitis are now felt to have been secondary to an ischemic event. In contrast to patients with acute mesenteric ischemia and extensive necrosis of the small bowel, the majority of patients with isolated colon ischemia follow a benign clinical course. Most patients present days, weeks, or months after the initial ischemic insult, and many may not have any recognizable antecedent episode of colon ischemia. However, some patients develop a fulminant form of the disease that causes colon infarction and death if not treated early. A high index of suspicion is necessary to make the diagnosis in the hospitalized patient. Endoscopy is recommended to confirm the diagnosis and the extent of injury and to monitor progression or resolution of disease. Aggressive management is of paramount importance to minimize the damage to the ischemic colon and reduce the otherwise high in-hospital mortality rate. Surgical intervention is indicated for patients with evidence of peritonitis or transmural infarction or perforation of the colon and for patients with chronic symptomatic colitis or stricture.

Colitis, Ischemic↗

Direct replacement of mycotic thoracoabdominal aneurysms.

Direct graft replacement with local debridement and prolonged administration of antibiotics was used in the treatment of six patients with mycotic thoracoabdominal aneurysms. The only early death occurred in a patient with systemic sepsis related to Staphylococcus aureus mycotic suprarenal aneurysm. Long-term survival of the remaining patients has been excellent: two patients died of unrelated causes at 5 and 6 years, respectively; one patient remains alive with known persistent infection at 5 years; and the remaining patients are alive with no evidence of infection at 1 1/2 and 10 years, respectively. Percutaneous aspiration of infected perigraft fluid with local instillation of antibiotics along with administration of intravenous antibiotics may provide palliation in selected patients with recurrent infections. In view of the magnitude of the problems associated with recurrent infection, life-time administration of antibiotics is recommended after in situ graft replacement of mycotic thoracoabdominal aneurysms.

Adult↗

Surgical management of renal artery aneurysm.

Between 1978 and 1990, 32 patients (15 men and 17 women; mean age 48 (range 15-83) years) underwent 35 operations for renal artery aneurysm (4.2% of 829 renal artery repairs). Eleven patients presented with acute symptoms (nine with hematuria, eight with abdominal pain, two with acute hypertension). Twenty-eight of the 32 patients had chronic hypertension. The diagnosis was confirmed by angiography in all but two. The mean diameter of the renal artery aneurysm was 1.7 (range 0.7-9.0) cm. Seventeen patients had concomitant renal artery stenosis; none of the aneurysms ruptured. Nephrectomy was performed in seven patients and excision of the aneurysm without reconstruction in five. Twenty patients underwent 23 reconstructions using lateral suture (three procedures), vein patch (three), saphenous vein (13), Dacron (three) or composite (vein and hypogastric artery) graft (one). Seven patients underwent ex vivo renal artery repair. There was no perioperative death or secondary nephrectomy. One postoperative graft occlusion was successfully revised. Hypertension improved in 50% of patients. The presence of hypertension, enlargement of a renal artery aneurysm, solitary kidney, bilateral involvement, acute hematuria or potential loss of kidney or renal function may be indications for surgical treatment of an aneurysm > 1.5 cm in diameter. A renal artery aneurysm of any size should be repaired in women who may become pregnant. Where there is branch involvement, ex vivo repair is the procedure of choice for renal salvage.

Adolescent↗

Cervicothoracic sympathectomy for Raynaud's syndrome.

Raynaud's syndrome is a clinical entity characterized by episodic vascular spasm and digital ischemia occurring in response to cold or emotional stimuli. Most patients with Raynaud's syndrome are successfully managed with medical therapy. Surgical sympathectomy is rarely performed and its use remains controversial. Of 3,219 patients seen with the diagnosis of Raynaud's disease, phenomenon or syndrome over the last 10 years at Mayo Clinic, 20 cervical or thoracic sympathectomies were performed in 14 (0.4%) patients. Of all patients who underwent cervico thoracic sympathectomy (68) for various reasons during the same time period, 20.5% (14/68) were performed for Raynaud's syndrome. Surgical sympathectomy was reserved for those rare patients with persistent, severe symptoms (pain, ulcer) despite intensive medical treatment. Surgical therapy was also used for those few patients with occupations involving exposure to cold and disabling, refractory symptoms in hopes of allowing them to return to work. Transaxillary (12 limbs) or supraclavicular (8 limbs) exposure and resection of the sympathetic chain with T1-T4 ganglions was usually performed. Initial resolution or improvement of symptoms was achieved in 19/20 (95%) of limbs. Both patients with digital ulceration healed. Although improved in some, persistent or recurrent symptoms were present in all patients after six months postoperatively. Increased sensitivity of digital vessels to circulating catecholamines, nerve fiber regeneration or incomplete sympathectomy have been postulated to lead to recurrence. Five patients developed Horner's syndrome postoperatively. A portion of the stellate ganglion was intentionally resected in 3 of the 5 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Hepatic artery aneurysms: evaluation and current management.

Twelve patients underwent surgical treatment for hepatic artery aneurysm (HAA) at Mayo Clinic between 1979 and 1991. Six patients presented with symptoms, while in six the HAA was asymptomatic. Two HAAs presented with rupture: one ruptured into the portal vein and one iatrogenic rupture occurred during cholecystectomy. Ultrasonography and computed tomography were important for diagnosis, while arteriography was used for planning of the operation. All HAAs were true aneurysms, with atherosclerosis being the etiology in 10 of 12 patients. The common hepatic artery was involved in 11 patients. Nine of 12 patients had aneurysms in other locations and half had major concomitant operations in addition to HAA repair. One patient had hepatic artery ligation, while in eleven the artery was reconstructed. Graft patency was poor (25%) when the gastroduodenal artery was excluded from the repair. No hepatic morbidity occurred. Mortality was 100% (1/1) for emergent operation, and 9.1% (1/11) in the elective setting. Because of the prevalence of other aneurysms, complete vascular evaluation and close follow-up are recommended.

Aged↗

Optimizing technical success of renal revascularization: the impact of intraoperative color-flow duplex ultrasonography.

PURPOSE: Technical problems with renal revascularization can be difficult to detect, especially with end points of transaortic renal endarterectomies or anastomosis of bypass grafts to small distal renal arteries. If missed, such technical mishaps may not be recognized until after operation, when the chance for timely renal salvage has often been lost. METHODS: To evaluate the value of newer color-flow duplex imaging, we performed intraoperative ultrasonography on 35 patients undergoing revascularization of 64 renal arteries, 29 patients undergoing transaortic endarterectomy, and 6 undergoing bypass grafting. Most patients (24/35; 69%) underwent concomitant aortic reconstruction. Ninety-four percent had hypertension, whereas 66% had associated chronic renal insufficiency. RESULTS: Technical abnormalities prompting operative revision were identified during surgery in 10.9% of reconstructed main renal arteries (7/64). These included two occlusions, three intimal defects, and one extrinsic tissue band after endarterectomy plus one graft anastomotic stenosis. Color-flow imaging revealed all of them. Technical defects were also associated with higher peak-systolic flow velocities (mean 2.62 m/sec; range 2.00 to 3.50 m/sec) than normal-appearing arteries (mean 1.34 m/sec; range 0.40 to 2.50 m/sec) (p = 0.004). Eighty-six percent of the defects (6/7) were immediately correctable. One patient required nephrectomy. Postoperative angiograms revealed two asymptomatic small branch-vessel occlusions (3%). Compared with preoperative levels (p < 0.01), both hypertension and renal insufficiency improved initially. The clinical outcome of patients requiring intraoperative revision did not differ from that of patients undergoing normal intraoperative studies. CONCLUSION: Intraoperative color-flow duplex detection and surgical correction of technical problems with renal revascularization have enhanced our technical success and been associated with long-term results comparable to those of patients undergoing normal intraoperative studies.

Aged↗

The role of intravenous fluorescein in the detection of colon ischemia during aortic reconstruction.

Intravenous fluorescein is an accurate predictor of small bowel viability, but its effectiveness in assessing colon perfusion during aortic surgery has not been evaluated. Over a 10 year period 186 of 3,306 patients undergoing aortic reconstruction received 500 to 1000 mg of intravenous fluorescein intraoperatively to evaluate colon viability. Prior history of colectomy, hypogastric or mesenteric arterial occlusive disease, or ruptured aneurysm placed these patients at risk to develop ischemic colitis. Patients were operated on for aneurysmal disease (n = 94), occlusive disease (n = 66), or a combination of both (n = 26): 171 exhibited uniform normal perfusion patterns under Wood's lamp illumination, while in 11 it was "patchy." None of these patients developed full-thickness ischemic colitis (observed specificity: 100%). Fluorescence of the rectosigmoid was absent in four patients. One of these patients with a ruptured aneurysm underwent immediate sigmoid resection, while three underwent inferior mesenteric artery reimplantation. The fluorescein pattern subsequently normalized in two patients, but one underwent sigmoid resection for an expanding mesenteric hematoma. The second patient recovered without complications. The final patient continued to show a segmental sigmoid defect and postoperatively developed full-thickness injury requiring sigmoidectomy. During the same period 18 other patients developed transmural colon ischemia from 3,120 aortic reconstructions (0.6%), with a mortality rate of 56%. None had received intraoperative fluorescein. Selective use of intravenous fluorescein may reduce the mortality of ischemic colitis following aortic reconstruction.

Aorta, Abdominal↗

Influence of complete revascularization on chronic mesenteric ischemia.

Complete revascularization for chronic intestinal ischemia is controversial. Fifty-eight patients (119 arteries) underwent mesenteric revascularization between 1981 and 1988. There were 46 women and 12 men (mean age: 63 years). Sixty percent of patients had three-vessel disease. Twenty-one patients underwent concomitant aortic reconstruction. Operative mortality was 10%. Four of the six deaths occurred in patients undergoing aortic surgery. Late graft failure occurred in five patients (10%). Five-year survival for patients with three-vessel involvement who underwent three-vessel repair was 73%, compared with 57% for two-vessel repair and 0% for one-vessel repair (p = NS). Similarly, graft patency in patients with three-vessel disease was highest in those patients who had complete revascularization (90%, 54%, and 0%, respectively) (p = NS). We conclude that increased graft patency and survival in patients with three-vessel disease was most frequent with complete revascularization. Diseased inferior mesenteric arteries should be repaired if feasible. Concomitant aortic operations should be avoided if possible.

Adult↗

Infected femorodistal bypass: is graft removal mandatory?

Infected lower extremity bypass grafts have been associated with high rates of limb loss. Traditionally treatment has included graft excision. To compare aggressive local treatment, without graft removal, with more conventional graft excision, we reviewed 38 consecutive patients with 39 infected lower extremity bypasses treated during the last 10 years. The grafts used were prosthetic in 33 cases, vein in 4, and composite in 2. Median follow-up was 2.7 years. Twenty-eight infected grafts were treated with either complete (14) or partial (14) graft removal. Nine new grafts were placed. Recurrent infection developed in five cases, and two patients died of complications of graft infection. Ten of 20 limbs at risk were lost. Eleven patients with patent bypasses (4 vein, 2 composite, 5 prosthetic) were treated without graft excision. Treatment of five patients in this group included muscle transposition. Five patients were treated with incision and drainage of abscesses, and one had excision of a persistent sinus tract. One patient underwent major amputation 6.3 years after treatment of graft infection. Limb salvage was significantly higher (p = 0.012, log-rank test) than in patients treated with graft excision. One patient died, and no recurrent infections developed; these were not significant differences compared with those having graft excision. We conclude that aggressive local treatment of infected lower extremity bypass grafts, including drainage, debridement, and muscle transposition may treat infection in selected patients without the need for graft removal and with rates of limb salvage superior to those obtained with excisional therapy.

Adult↗

Reconstruction of large veins for nonmalignant venous occlusive disease.

To evaluate the effectiveness of venous grafting, we reviewed the management and clinical course of 28 patients (21 males and seven females) who underwent 29 reconstructions of large veins for benign disease. There were 12 patients with superior vena cava (SVC) syndrome, two with subclavian vein thrombosis, and 15 with occlusion of the inferior vena cava (IVC) or iliac veins. One of these patients underwent both IVC and SVC reconstructions. Reconstruction of the SVC was performed with spiral saphenous vein graft (SSVG) in nine patients and expanded polytetrafluoroethylene (ePTFE) in three. All seven straight SSVGs had documented patency at a median of 7 months (2 weeks to 5 years) after reconstruction. Six patients had complete relief of symptoms. Two patients with bifurcated SSVG had early occlusion of one graft limb. Two of the three ePTFE grafts needed early thrombectomy. One graft reoccluded at 6 months and two were patent at 2 and 5 years. The two subclavian vein reconstructions with axillary-jugular ePTFE grafts with an arteriovenous fistula had documented early patency. Both patients had rapid resolution of symptoms. The IVC or iliac vein was reconstructed with ePTFE graft in 11 patients, SSVG in three, and Dacron in one. A femorofemoral arteriovenous fistula was added in eight patients with ePTFE grafts. Seven of the 11 ePTFE grafts had documented patency at the last follow-up (median 9 months; range 2 weeks to 5 years). None of the three SSVGs had documented long-term patency. The one Dacron cavoatrial graft occluded at 3 years. A straight SSVG continues to be our first choice for SVC replacement. Short, large-diameter ePTFE grafts perform the best in the abdomen. Femorocaval or long iliocaval grafts need an arteriovenous fistula to maintain patency. Long-term patency after closure of the fistula is still unknown. Femorocaval grafts with poor venous inflow have limited chance of success. Failed or failing grafts may be salvaged by early thrombectomy. Venous reconstruction to treat selected patients with symptoms with large vein occlusion continues to be a viable option.

Adult↗

Primary venous leiomyosarcoma: a rare but lethal disease.

Primary venous leiomyosarcoma is rare, only 197 patients have been reported. To examine progress in diagnosis, treatment, and clinical outcome, we retrospectively reviewed data of 13 patients, 12 women and one man (mean age, 55 years; range, 19 to 75 years), who in the last 35 years underwent surgical treatment for primary venous leiomyosarcoma at our institution. The tumor arose from the inferior vena cava in eight, iliac vein in two, ovarian vein in one, and greater saphenous vein in two patients. Primary venous leiomyosarcoma was detected by physical examination in nine patients, symptoms were present in six. The 13 patients underwent 16 surgical procedures to resect primary (12), recurrent (2), or metastatic (2) tumors. Local excision alone was performed in seven, and local excision with reconstruction of the inferior vena cava or iliac vein was performed in six patients. The tumor was greater than 10 cm in eight patients. The perioperative mortality rate was 15% (2 of 13). Median survival of the 11 early survivors was 3.5 years (range, 6 months to 17 years). Currently five patients are alive (four of them free of known tumor), with a median survival of 3 years (6 months to 17 years) after surgery. Of the eight deceased patients, primary venous leiomyosarcoma recurred after resection in six. Tumor recurrence was not affected by tumor grade, size, or adjuvant treatment. Although early detection with modern imaging techniques could potentially be of benefit, wide local excision with selective venous reconstruction affords the only hope for prolonged survival.

Adult↗

Spinal cord injury in experimental thoracic aortic occlusion: investigation of combined methods of protection.

The efficacy of combined methods of spinal cord protection during thoracoabdominal aortic reconstruction was evaluated because a recent clinical study failed to substantiate the value of cerebrospinal fluid drainage when used alone in the prevention of paraplegia. The effect of cerebrospinal fluid drainage and aortofemoral shunting were analyzed with regard to neurologic outcome and spinal cord blood flow in a model of thoracic aortic occlusion. In addition, we studied the use of motor-evoked potentials as compared with somatosensory-evoked potentials in monitoring cord perfusion. Thirty-two dogs underwent proximal and distal thoracic aortic occlusion for 60 minutes. The control group (n = 8) underwent thoracic aortic cross-clamping only. Spinal cord protection was used in three groups: cerebrospinal fluid drainage alone (n = 8), aortofemoral shunting alone (n = 8), and cerebrospinal fluid drainage and aortofemoral shunting (n = 8). Neurologic outcome improved in all treatment groups as compared with controls (p less than 0.001). The addition of cerebrospinal fluid drainage to aortofemoral shunting did not further improve neurologic outcome. Spinal cord blood flow measured with microspheres in the lumbar gray matter was significantly higher in the dogs with aortofemoral shunting (+/- cerebrospinal fluid drainage) as compared with those with cerebrospinal fluid drainage alone (p less than 0.05) or the controls (p less than 0.001). Aortofemoral shunting also prevented the development of acidosis and hyperglycemia. Loss or changes in amplitude and latency of motor-evoked potentials did not distinguish between the groups. Loss of somatosensory-evoked potentials had a high sensitivity (92%) but lower specificity (68%) in predicting neurologic injury, whereas loss of motor-evoked potentials had a high specificity (100%) but a very low sensitivity (16%). We conclude that cerebrospinal fluid drainage or aortofemoral shunting significantly improve spinal cord blood flow and neurologic outcome. The greatest increase in spinal cord blood flow was seen with aortofemoral shunting, which also prevented metabolic disturbances of reperfusion. Although the addition of cerebrospinal fluid drainage to aortofemoral shunting was the only group in which no neurologic injury occurred, this group did not have a significant improvement in outcome when compared with aortofemoral shunting alone. Spinal cord ischemia was more accurately detected with somatosensory-evoked potentials when aortofemoral shunting was used, whereas motor-evoked potentials recorded from the spinal cord were not sensitive enough to predict neurologic injury.

Analysis of Variance↗