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H D Hildebrand

Publications and source records attributed to H D Hildebrand.

10 recordsLinked to original sources
PubMed1997

Progress in abdominal aortic aneurysm surgery: four decades of experience at a teaching center.

The purpose of this study was to examine the changing trends in surgical management of patients with abdominal aortic aneurysms at a tertiary care teaching hospital over the past 40 years, by analysis of demographic data, perioperative variables and outcomes on all patients having abdominal aortic aneurysm surgery between 1955 and 1993. Some 1604 abdominal aortic aneurysms were assessed. The annual rate of abdominal aortic aneurysm surgery increased from 17.6 to 67.8 cases per year. The non-ruptured to ruptured abdominal aortic aneurysm ratio increased from 2.4:1 in the first decade to 3.4:1 in the last 5 years. In non-ruptured abdominal aortic aneurysm repairs, the following variables changed over the four decades: patients age over 80 years increased (2.4% to 8.0%; P<0.04), concomitant lower-limb occlusive disease increased (12.2% to 23.7%; P<0.02), prevalence of smaller aneurysms (4-6 cm) increased (16.0% to 54.2%; P<0.0001); intraoperative hypotension decreased (9.0% to 0.7%; P<0.0001), postoperative hemorrhage decreased (8.2% to 0.0%, P<0.0001), postoperative leg ischemia decreased (5.7% to 1.1%; P<0.02) and postoperative amputation rate decreased (3.2% to 0.0%; P<0.03). There was a significant decrease in perioperative mortality (17.0% to 3.4%; P<0.0001). For ruptured aneurysms, early operation (within 1 h of admission) increased from 8.7% to 55.8% (P<0.0001), prevalence of intraoperative hypotension decreased (50.0% to 23.5%; P<0.001), and major venous injury decreased (18.0% to 5.2%; P<0.05). Mortality, however, did not decrease significantly (54.2% to 44.2%; P=0.32). In conclusion, there was a significant decrease in mortality and morbidity associated with non-ruptured abdominal aortic aneurysm repair over the four decades studied. In addition, older patients with smaller aneurysms and more co-morbid conditions were operated on during this period. Mortality for patients operated on for ruptured abdominal aortic aneurysm repair has not changed significantly.

Adult↗
PubMed1996

Predictors of death in nonruptured and ruptured abdominal aortic aneurysms.

PURPOSE: This study evaluated perioperative variables to predict death in nonruptured and ruptured abdominal aortic aneurysm (AAA) surgery. METHODS: A consecutive review of all patients who underwent AAA surgery from January 1984 to December 1993 was carried out. Perioperative variables were analyzed with univariate and multivariate statistical models to predict mortality rates. RESULTS: Four hundred seventy-eight patients with nonruptured AAAs and 157 patients with ruptured AAAs were studied. In patients with nonruptured AAAs, the mortality rate was 3.8%. Using stepwise logistic regression analysis, independent predictors of death were perioperative myocardial infarction (odds ratio [OR], 5.0; p < 0.01), prolonged postoperative ventilation (OR, 4.0; p < 0.01), history of peripheral vascular disease (OR, 2.9; p < 0.01), preoperative renal dysfunction (OR, 2.7; p < 0.01), and history of congestive heart failure (OR, 2.6; p < 0.03). In patients with ruptured AAAs, the mortality rate was 46%. Analysis of preoperative variables using multivariate stepwise logistic regression found predictors of death to be preoperative unconsciousness (OR, 3.1; p < 0.01), advanced age (OR, 1.9; p < 0.01), and cardiac arrest (OR, 1.8; p < 0.05). In patients who survived the initial surgery for ruptured AAA, a second stepwise logistic regression model found independent predictors for subsequent postoperative death to be coagulation disorder (OR, 7.9; p < 0.01), ischemic colitis (OR, 6.4; p < 0.01), inotropic support beyond 48 hours (OR, 4.8; p < 0.01), delayed transport to operating room (OR, 4.6; p < 0.01), advanced age (OR, 4.4; p < 0.01), perioperative myocardial infarction (OR, 4.0; p < 0.05) and postoperative renal dysfunction (OR, 3.7; p < 0.01). CONCLUSION: Prolonged ventilation, perioperative myocardial infarction, a history of peripheral vascular disease, preoperative renal dysfunction, and a history of congestive heart failure are independent predictors of perioperative death in patients with nonruptured AAAs. For patients with ruptured AAAs, mortality rates can be estimated before surgery using age, level of consciousness, and cardiac arrest. For patients who survive the initial surgery for ruptured AAA, subsequent mortality rates can also be predicted.

Aged↗
PubMed1992

Major vessel excision in retroperitoneal lymph node dissection.

Retroperitoneal malignant tumours, both primary and metastatic, may involve surrounding structures such as the aorta and vena cava, making complete tumour excision difficult. En bloc resection of major blood vessels should be considered in such cases. The authors describe three patients who underwent excision of major blood vessels with retroperitoneal lymph node dissection. Two patients had aortic resection with placement of a Dacron tube graft, and one had excision of the vena cava from above the renal vessels to the level of the common iliac veins with distal venous ligation. The low complication rate confirms the feasibility of excising major blood vessels to accomplish complete retroperitoneal lymphadenectomy.

Adolescent↗
PubMed1989

Results of vascular surgery in younger versus older patients.

We reviewed the results of reconstructive surgery at the aortoiliac and femoropopliteal levels in two age groups. Although patency rates were similar, when failure occurred, the amputation rate in the group under age 50 was almost three times that in the group over age 60. Practical application can be made in the preoperative preparation of the younger patient presenting with lower limb occlusive disease. More research of arteriosclerosis in the young is needed.

Adult↗
PubMed1987

Preoperative predictors of mortality risk in ruptured abdominal aortic aneurysm.

A retrospective review of 106 cases of ruptured abdominal aortic aneurysm was undertaken to determine whether analysis of preoperative variables might be predictive of death in this condition. Thirty variables were analyzed by univariate and multivariate methods. Statistically significant differences between survivors and nonsurvivors were noted for 12 of 30 factors when analyzed with univariate tests. Multivariate analysis with stepwise logistic regression demonstrated that elevation of the unmeasured anion gap, a history of congestive heart failure, and the patient's level of consciousness before operation were significantly and independently associated with death. Coefficients generated from this model allowed stratification of patients into four risk groups with respective mortality rates of 100%, 75%, 28%, and 12%. We conclude that it is possible to assign a mortality risk score to individual cases of ruptured abdominal aortic aneurysm on the basis of readily available clinical and laboratory parameters. A prospective study to address this question seems justified.

Acid-Base Equilibrium↗
PubMed1980

Mesenteric vascular disease.

Mesenteric vascular disease continues to be associated with an extremely high mortality. It is not necessarily a disease of old age: 20 of the 75 patients in our series were less than 60 years of age. In retrospect, earlier diagnosis and a more aggressive approach could have improved the survival rate of 17.3 percent. Surgeons have been slower to accept revascularization of the bowel compared with similar procedures in the extremities and other organs. A greater understanding of the disease and the benefits of surgery should yield better results. Early laparotomy with aortomesenteric grafting and planned resection 24 hours later, as used in one patient, is advocated as a useful technique.

Adolescent↗
PubMed1975

Ruptured abdominal aortic aneurysm.

A total of 131 surgically treated ruptured abdominal aortic aneurysms have been reviewed. Factors affecting morbidity and mortality rates have been analyzed. In our experience very little improvement has occurred in the last 10 years and the question is raised whether a plateau has been reached in the management of this catastrophic disease. Patient selection is not considered to be the key to better results, since some operated patients inevitably die. Improved technique with better, more rapid control of blood loss, especially from venous tears, will continue to yield better results. Eighty-six nonoperative cases have been studied. Diagnostic accuracy is lower than it should be, often leading to delayed surgery or death.

Age Factors↗