In-hospital mortality of ruptured abdominal aortic aneurysm

Background: New Zealand, like Australia, has a widely dispersed population in towns at long distances from the main centres. We set out to estimate the in‐hospital mortality rate for ruptured abdominal aortic aneurysms in New Zealand and identify factors associated with mortality. Methods: Data were gathered prospectively as part of the Vascular Society of New Zealand’s continuous audit programme of all member surgeons. Data collection was validated by random record audit. In‐hospital mortality of ruptured abdominal aortic aneurysms, defined as death during hospital admission irrespective of cause, was determined for the period 1993–2005. Along with other performance indicators, differences in outcomes were assessed to take into account the trend over the time period, hospital size and number of non‐operative admissions. Results: Of the 740 patients admitted with a mean age of 73.9 ± 8.5 years, 78% were men and 17.8% were declined an operation. The in‐hospital mortality was 48.3% and the operative mortality was 37.8%. With univariate analysis increasing patient age, American Society of Anesthesiology score, hospital size and female sex were predictors of in‐hospital mortality. Only age and American Society of Anesthesiology score were independent predictors of operative mortality. Women were less likely to have surgery. Conclusion: Over the past 13 years in‐hospital mortality of ruptured abdominal aortic aneurysms in New Zealand remained unchanged. In provincial hospitals the operative outcomes were satisfactory, but the reported number not offered surgery was higher.     

Risk-adjusted analysis of early mortality after ruptured abdominal aortic aneurysm repair

PURPOSE: Ruptured abdominal aortic aneurysms (RAAAs) continue to result in early mortality in up to 50% of patients. Additionally, it remains difficult to compare outcomes given the variability in patient comorbidities and presentation. The purpose of this study was to describe an instrument that permits the prospective analysis of outcomes after RAAA repair while adjusting for the variability in preoperative risk. METHODS: Consecutive patients undergoing attempted open RAAA repair over a 5-year period (1999 to 2003) at our center were reviewed. Thirty-day or in-hospital mortality was the main outcome variable. Preoperative mortality risk was estimated for each patient by using a validated modification of the POSSUM scoring system (V-POSSUM). A risk-adjusted cumulative sum method (RA-CUSUM) was used to compare observed versus predicted outcomes by assigning a risk-adjusted score, based on log-likelihood ratios, to each patient. These scores were sequentially plotted with preset control limits to allow for "signaling" when results were substantially different from expected (doubling or halving of odds ratios). RESULTS: A total of 136 patients were reviewed, with an early mortality rate of 45.6%. V-POSSUM scores were accurate in predicting mortality for the entire cohort, with an observed-to-predicted mortality ratio of 0.92 (P = .80). Each patient's risk-adjusted score was plotted sequentially. In one segment of the resulting plot, the graph adopted a negative slope and crossed the lower control limit, indicating improved results compared with predicted. CONCLUSIONS: V-POSSUM scores in this series accurately predicted early mortality after RAAA surgery. The RA-CUSUM method allows for the prospective evaluation of outcomes, while taking into account patient variability. In the current study, this resulted in the identification of a series of patients who had improved outcomes compared with predicted.     

Outcomes of surgical management of ruptured abdominal aortic aneurysm

Background Ruptured abdominal aortic aneurysms have remained a challenge to the cardiovascular surgeon. They are rapidly fatal if left untreated with reported mortality rates approaching 50%. Urgent surgery is the accepted modality of therapy. We report the outcome of surgical management of this subset of patients. Methods We retrospectively analyzed case records of 36 consecutive patients who underwent surgery for ruptured infra-renal abdominal aortic aneurysm (RAAA) at our institute between January 1990 and January 2005. Thoraco-abdominal & iliac aneurysms were excluded from the study. Mean age was 59 years±14.3 (Range—20 to 81 years). 33 of the patients were operated as an emergency. Systemic hypertension, renal dysfunction and coronary artery disease were the major co-morbid conditions. Results Hospital mortality was 42% (15/36 patients). 6 patients died of diffuse bleeding and coagulopathy, 5 patients had peri-operative myocardial infarction, 2 patients developed acute renal failure, and 1 each died of large bowel gangrene and massive haemoptysis. Follow up ranged from 2 to 9 years with a mean of 4.3 years. There were no major morbidities at mid-term follow-up. Conclusion Emergency surgery for RAAA continues to be associated with a high mortality rate, despite the improvements in surgical techniques and post-operative care. Early detection and subsequent treatment would circumvent the high mortality associated with these patients.     

Factors affecting survival after ruptured abdominal aortic aneurysm

To identify the factors affecting the high mortality rates associated with ruptured abdominal aortic aneurysm (AAA), a review was made of the records of 81 patients treated surgically between 1972 and 1983. Correlation of data with survival and predictive value of preoperative findings were studied. The mortality rate was 43.2%; there was a 29.2% mortality rate among those surviving the day of surgery. Patient-determined variables associated with deaths included age more than 76 years, hematocrit less than 30% and acute abnormality detected by ECG at admission, and suprarenal extension or free rupture of the AAA. Survival could be predicted with only 70% accuracy with a computerized discriminant function based on age and hematocrit and blood pressure values determined at admission. Events following admission associated with death were precipitous fall or persistently low level of preoperative blood pressure, technical complications, and postoperative organ failure. Although the patient's ultimate outcome after ruptured AAA is partly determined before intervention of the physician, efforts to address events resulting in death after admission by improving rapid diagnosis, early resuscitation, and prompt flawless surgery can increase survival.     

Colon infarction after ruptured abdominal aortic aneurysm.

Colon infarction is a lethal complication of ruptured abdominal aortic aneurysm. We compared multiple anatomic, hemodynamic, and clinical features in 25 patients with ruptured abdominal aortic aneurysm who suffered colon ischemia and 25 initial survivors of ruptured abdominal aortic aneurysm in whom this complication did not develop. Prior impressions notwithstanding, preoperative shock or volume administration did not correlate with the development of colon ischemia, nor did aneurysm location, cross-clamp site, graft type, or inferior mesenteric artery patency. However, patients with colon ischemia had a significantly lower perioperative cardiac output and were significantly more likely to have received alpha-adrenergic vasoconstrictor agents. Seventeen patients (68%) with colon ischemia died compared with nine patients (36%) without colon ischemia. Perioperative maintenance of cardiac output and avoidance of alpha-adrenergic vasopressor agents are critical elements in prevention of this lethal complication.     

Sigmoid colon exteriorization after ruptured abdominal aortic aneurysm

A 74-year-old man in shock was transferred to our hospital. A ruptured abdominal aortic aneurysm was diagnosed by computed tomography and an emergency operation was thereafter performed. At operation, a massive hematoma was encountered in the retroperitoneal space and a standard aneurysmectomy with bifurcated graft replacement was carried out. At the end of the operation, signs of sigmoid colonic ischemia were recognized, including mild discoloration and bowel spasm. After considering the recovery or deterioration from colonic ischemia, we chose to exteriorize the sigmoid colon. On the 4th postoperative day, patchy ischemic areas of an elevated sigmoid colon were noticed to worsen and as a result, we were forced to perform a sigmoid colectomy with end colostomy. Thereafter, the patient developed multisystem organ failure, but he recovered gradually. The patient was discharged from the hospital 3 months after the initial operation. As a complication after surgery for abdominal aortic aneurysms, colonic ischemia remains a serious problem, especially in cases of ruptured AAA. It is generally better to avoid an operation for both abdominal aortic aneurysms and a colon resection at the same time. In this case, an exteriorization of the sigmoid colon was selected for the 1st operation in order to treat a ruptured abdominal aortic aneurysm. This surgical modality was found to be useful for making a correct diagnosis of colonic ischemia before the perforation, while a 2nd look operation for colonic ischemia could thus be performed under conditions of a reduced risk of infection to the prosthetic graft. These operative procedures were considered to be important factors in saving the patient's life.     

The post-operative mortality of ruptured abdominal aortic aneurysm repair.

INTRODUCTION: Late peri-operative death after ruptured abdominal aortic aneurysm (RAAA) repair is usually due to multiple-organ failure. The aim of this study was to identify any factors that are associated with mortality in this group of patients. METHODS: A retrospective case-note review of a single decade's operative experience of RAAA repair in a single centre. Only those patients with confirmed rupture at laparotomy were included. Sixty-three pre- intra- and post-operative variables were recorded where possible for each patient who survived surgery and the initial 24-hours post-operatively. Multi-variate analysis was performed using stepwise logistic regression. The P-POSSUM, RAAA-POSSUM, RAAA-POSSUM (physiology only), V-POSSUM, and V-POSSUM (physiology only) models were all compared to determine how each performed in these patients. RESULTS: Two hundred and twenty-three cases of confirmed RAAA were identified, of whom 139 survived the operation and initial 24-hours post-operatively. In-hospital mortality in this group of patients was 32.4%. Variables significantly associated with mortality after multi-variate analysis, were low intra-operative systolic blood pressure, the presence of a consultant anaesthetist at the initial operation and the development of cardiac, renal or gastro-intestinal complications. All POSSUM models except the V-POSSUM and P-POSSUM (physiology only) models demonstrated no significant lack of fit in this dataset. DISCUSSION: Factors associated with delayed peri-operative death after RAAA are not the same as those previously found to be associated with overall peri-operative mortality after RAAA repair.     

Abdominal compartment syndrome after ruptured abdominal aortic aneurysm

Abdominal Compartment Syndrome (ACS) is an increasingly recognized syndrome of intra-abdominal hypertension and generalized physiological dysfunction in critically ill patients. Patients suffering a ruptured abdominal aortic aneurysm (rAAA) are at risk of developing ACS. The objective of the study was to compare the current views on the importance, prevalence and management of ACS after rAAA among Australian vascular surgeons and intensivists. A questionnaire was mailed to 116 registered vascular fellows from the Royal Australasian College of Surgeons and 314 registered fellows of the Joint Faculty of Intensive Care Medicine. Data were collected on the prevalence and importance of ACS after rAAA and whether prophylactic measures were or should be taken to prevent ACS. Hypothetical clinical scenarios representing a range of ACS after rAAA were also presented. The responses were compared using chi(2)-test and t-test. Sixty-seven per cent (78 of 116) of surgeons and 39% (122 of 314) of intensivists responded. Both groups estimated the prevalence of ACS after rAAA as between 10 and 30% and considered it an important entity. Only 30% of surgeons and 50% of intensivists suggested routine intra-abdominal pressure (IAP) monitoring. In patients with borderline IAP (18 mmHg), both groups believed that surgical intervention was unnecessary. Intensivists were more inclined to suggest surgical intervention for clinically deteriorating patients with an increased IAP (30 mmHg) compared with surgeons. Forty-three per cent of intensivists and 17% of surgeons suggested prophylactic (leaving the abdomen open) measures to prevent ACS in high-risk patients. Surgeons and intensivists have similar views on the prevalence and clinical importance of ACS after rAAA. Intensivists more frequently monitored IAP and suggested both early prophylactic and therapeutic intervention for ACS based on physiological and IAP findings.     

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.     

Aortic-caval fistula from ruptured abdominal aortic aneurysm.

Four cases of spontaneous aorto-caval fistula are reported. All cases were successfully treated by suture of the fistula from the inside of the aortic aneurysm, which was replaced by a dacron graft. All patients are alive and well at follow up after one, three, four and twelve years, respectively. In one patient pulmonary and circulatory haemodynamics were recorded preoperatively as well as in the early and late postoperative period. Preoperative high pulmonary artery and capillary wedge pressures and cardiac output were rapidly reduced to almost normal values after the operation. An intrapulmonary shunt fraction of 58 % preoperatively was reduced to 15 % shortly after closure of the fistula. Possible mechanisms causing the high pulmonary shunt fraction are discussed.     

Results of 101 ruptured abdominal aortic aneurysm repairs from a single surgical practice

Hypotheses The results of ruptured abdominal aortic aneurysm repairs from a solo community hospital-based practice are comparable to those reported from large university referral medical centers. Patients younger than 70 years, arriving in the emergency department with stable hemodynamics, and undergoing prompt operation have better outcome. DESIGN: A retrospective review from an ongoing vascular surgery registry. SETTING: Two midsized (300-bed) community hospitals. One hundred one consecutive patients with ruptured abdominal aortic aneurysms who were undergoing open surgical repair by a single surgeon (S.S.H.) during a 21-year period were reviewed. MAIN OUTCOME MEASURES: Operative mortality; cardiac, pulmonary, renal, and gastrointestinal complications; and coagulation abnormalities were recorded. Iatrogenic complications and length of hospital stay were noted. Preoperative and intraoperative factors affecting mortality were studied. RESULTS: Fifty-three patients survived ruptured abdominal aortic aneurysm repair (operative mortality, 47.5%). A favorable outcome was observed in patients (1). younger than 70 years, (2). with a hematocrit of more than 35% at presentation, and (3). with emergency department to operating room times of less than 120 minutes. Increasing experience of the surgeon did not result in improved survival. CONCLUSION: The results of ruptured abdominal aortic aneurysm repairs from community-based practice are comparable to those reported from university referral medical centers.