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.     

Validity of the Hardman index to predict outcome in ruptured abdominal aortic aneurysm

This study assessed the validity of the Hardman index in predicting outcome following open repair of ruptured abdominal aortic aneurysm and whether this scoring system can be used reliably to select patients for surgical repair. Patients undergoing open repair of ruptured abdominal aortic aneurysm in two university teaching hospitals over a 5-year period were identified from a computerized hospital database. Thirty-day mortality was the main outcome measure. Five Hardman index factors were calculated and related to outcome retrospectively. There were 178 patients with a mean age of 73.9 years (range 51-94) and a male to female ratio of 5.4:1. The overall in-hospital mortality was 57.3% (102/178). Univariate analysis of risk factors showed that age >76 years (P = 0.007, odds ratio [OR] 2.34, 95% confidence interval [CI] 1.26-4.37) and electrocardiograghic evidence of ischemia on admission (P = 0.002, OR 3.75, 95% CI 1.57-8.93) were associated with high mortality. However, loss of consciousness (P = 0.155, OR 1.56, 95% CI 0.85-2.86), hemoglobin <9 g/dL (P = 0.118, OR 1.89, 95% CI 0.85-4.22), and serum creatinine >0.19 mmol/L (P = 0.691, OR 1.25, 95% CI 0.42-3.70) were not significant predictors of mortality. Using a multivariate analysis, age >76 years (P = 0.043, OR 2.29, 95% CI 1.03-5.11) and myocardial ischemia (P = 0.029, OR 2.93, 95% CI 1.12-7.67) were again found to be the significant predictors of mortality. The operative mortality was 44%, 46%, 68%, 79%, and 100% for Hardman scores of 0, 1, 2, 3, and 4, respectively. No patient had a score of 5. The Hardman index is not a reliable predictor of outcome following repair of ruptured abdominal aortic aneurysm. High-risk patients may still survive and should not be denied surgical repair based on the scoring system alone. Further evaluation of the risk factors is required to reliably and justifiably exclude those patients in whom the intervention is inappropriate.     

The Hardman index in patients operated on for ruptured abdominal aortic aneurysm: A systematic review

BACKGROUND: The aims of the present study were to (1) analyze preoperative predictors for outcome suggested by Hardman and surgical mortality after open repair and endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA), and (2) further evaluate the Hardman index in a systematic review. METHODS: Patients operated on for rAAA during a 5-year period between 2000 and 2004 were scored according to Hardman-1 point for either age >76 years, loss of consciousness after presentation, hemoglobin <90 g/L, serum creatinine >190 micromol/L or electrocardiographic (ECG) signs of ischemia-with blinded evaluation of ECGs by a specialist in clinical physiology. The results were included in a systematic review of studies evaluating the Hardman index. RESULTS: In-hospital mortality after operation was 41% (67/162). There was no difference in in-hospital mortality between open repair (n = 106) and EVAR (n = 56), whereas the Hardman index was associated with operative mortality in our institution and in the systematic review of 970 patients (P < .001). Mortality rate in patients with Hardman index > or =3 was 77% in the pooled analysis. A full data set of all five scoring variables was obtained in 94 (58%) of 162 patients in our study, and potential underscoring was thus possible in 68 patients. Of the available ECGs, 12 (8.7%) of 138 were judged nondiagnostic. Five studies did not state their missing data on ECG and hemoglobin and serum creatinine concentrations, nor did they specify the criteria for ECG ischemia. CONCLUSIONS: A strong correlation between the Hardman index and mortality was found. A Hardman index > or =3 cannot be used as an absolute limit for denial of surgery. The utility of the Hardman index seems to be impeded by variability in scoring resulting from missing or nondiagnostic data.     

Validity of the Glasgow Aneurysm Score and the Hardman Index in predicting outcome after ruptured abdominal aortic aneurysm repair

BACKGROUND: The Glasgow Aneurysm Score and the Hardman Index have been recommended as predictors of outcome after repair of ruptured abdominal aortic aneurysm (AAA). This study aimed to assess their validities. METHODS: Patients admitted to a single unit with a ruptured AAA over a 2-year interval (2000-2001) were identified from a prospectively compiled database. Hospital records of all patients undergoing attempted operative repair were reviewed. The Glasgow Aneurysm Score and the Hardman Index were calculated retrospectively and related to clinical outcome. RESULTS: One hundred patients were admitted with a ruptured AAA. Of these, 82 underwent attempted operative repair and were included in the study: 68 men and 14 women, of median age 73 (range 54-87) years. Thirty (37 per cent) patients died after the operation. The Glasgow Aneurysm Score was a poor predictor of postoperative mortality. The area under the Receiver-Operator Characteristic curve was 0.606 (P = 0.112, 95 per cent c.i. 0.483-0.729). Similarly, the Hardman Index failed to predict postoperative mortality accurately (P = 0.211, chi(2) for trend). Of nine patients in this series with three or more Hardman criteria, generally held to be fatal, six survived. CONCLUSION: Contrary to previous reports, The Glasgow Aneurysm Score and the Hardman Index were poor predictors of postoperative mortality after repair of a ruptured AAA in this study.     

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.     

Comparison of POSSUM scoring and the Hardman Index in selection of patients for repair of ruptured abdominal aortic aneurysm

BACKGROUND: The aim was to assess to what extent the POSSUM (Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity) and Hardman scoring systems were predictive of outcome after surgery for ruptured abdominal aortic aneurysm (RAAA). METHODS: From January 1990 to December 2001, 232 patients presented with RAAA. Forty-one were treated conservatively and all died; the remainder had emergency surgery. The case notes of all but three of these patients were reviewed retrospectively. POSSUM and Hardman scores were calculated and related to mortality. RESULTS: The mortality rate after emergency repair was 54 per cent (104 of 191). The physiology-only POSSUM score specific for RAAA and the Hardman Index score were both significantly associated with increased mortality after operation (P < 0.001). Most non-operated patients were in the highest risk bands. CONCLUSION: Both POSSUM and Hardman scoring systems predicted outcome after emergency surgery for RAAA. The Hardman Index was simpler to calculate, but POSSUM identified a higher number of patients at risk. Risk scoring may help identify patients with RAAA for whom surgery is futile.     

Applicability of Glasgow Aneurysm Score and Hardman Index to elective endovascular abdominal aortic aneurysm repair

OBJECTIVE: This retrospective study aimed to explore the role of Glasgow Aneurysm Score (GAS) and Hardman Index (HI) in predicting outcome after elective endovascular aneurysm repair (EVAR). METHODS: All 71 patients who underwent elective EVAR in a single centre over 9 years were reviewed. Clinical data were used to classify patients into the three standard GAS tertiles and to score patients according to the HI. RESULTS: Fifty-one patients scored > or = 77 according to GAS. Actual and predicted mortality in this group were 3.9% and 9.3%. Seventeen patients scored between 69 and 77 with actual and predicted mortality of 0% and 4.1%. Three patients scored less than 69 with actual and predicted mortality of 0% and 2.4%. Ten patients scored > or = 3 on the HI with actual and predicted mortality of 10% and 100%, respectively. Twenty-four patients scored 2 with actual and predicted mortality of 4.2% and 55%. Twenty-seven patients scored 1 with actual and predicted mortality of 0% and 28%, respectively. Ten patients scored 0 with actual and predicted mortality of 0% and 16%, respectively. The chi(2) test showed extremely significant p value of 0.0001 in case of HI, and p value of 0.0800 for GAS, slightly less significant, probably due to the small sample size. CONCLUSION: Contrary to their role in ruptured and open aortic aneurysm repair, GAS and HI overestimate both mortality and morbidity following EVAR and are poor predictors of outcome.     

Preoperative arterial blood lactate levels as a predictor of hospital mortality in patients with a ruptured abdominal aortic aneurysm

Purpose

To establish if preoperative arterial blood lactate (Lac) is a factor related to hospital death for patients with a ruptured abdominal aortic aneurysm (rAAA).

Methods

The subjects were 55 patients who underwent surgery for an rAAA in a single institution between July, 2000 and November, 2009. Patients were divided into a survivor group and a non-survivor group. We compared the preoperative Lac levels and other data between the groups.

Results

There were ten hospital deaths. On univariate analysis, preoperative Lac levels, shock vital, cardiopulmonary resuscitation, Hardman index ≥3, and Glasgow aneurysm score ≥84 were significantly higher and preoperative hemoglobin was significantly lower in the non-survivor group. The postoperative mortality rate tended to increase with preoperative Lac levels. The mortality rate of patients with a preoperative Lac level higher than 9 mmol/l was 86 %. Those factors that had significant association with hospital mortality on univariate analysis were consecutively analyzed using multivariate logistic regression analysis. The multivariate logistic regression analysis revealed that a preoperative Lac level >9 mmol/l was the only independent risk factor of hospital mortality.

Conclusion

The preoperative Lac level of patients with a rAAA may be a predictor of their prognosis.     

Decrease of mortality of ruptured abdominal aortic aneurysm after centralization and in-hospital quality improvement of vascular service

Our aim was to determine whether organizational changes could improve the outcome after ruptured abdominal aortic aneurysm (RAAA). Regional centralization and quality improvement in the in-hospital chain of treatment of RAAA included strengthening of the emergency preparedness and better availability of postoperative intensive care. During the reorganization, all patients with RAAA were admitted to Helsinki University Central Hospital (HUCH) from Helsinki and Uusimaa district. RAAA patients in the hospital district of Helsinki and Uusimaa between 1996 and 2004 were identified. The study period was divided into three periods: I, control; II, change; and III, present. Of the total of 626 patients with RAAA, 352 (56%) were admitted to the HUCH, of whom 315 (90%) underwent surgery. During the study period, population-based mortality decreased from 77% to 56% (P < 0.001) and 90-day mortality, from 54% to 28% (P = 0.002). Operative 30-day mortality was 19% during the third period and lower than previously (P = 0.001). Our results seem to argue in favor of centralization of emergency vascular services with adequate manpower and operative expertise in the first line and with availability of closed-unit postoperative critical care to achieve better results as these measures were associated with a positive impact on survival.     

Value of risk scores in the decision to palliate patients with ruptured abdominal aortic aneurysm

Background

The aim of this study was to develop a 48‐h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care.

Methods

Data from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C‐statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified.

Results

Data from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48‐h mortality in the IMPROVE data was reasonable (C‐statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C‐statistic was estimated compared with using age alone.

Conclusion

The assessed risk scores did not have sufficient accuracy to enable potentially life‐saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non‐intervention rates, while respecting the wishes of the patient and family.     

Hypotensive resuscitation in patients with ruptured abdominal aortic aneurysm.

BACKGROUND: The technique of hypotensive resuscitation in haemorrhagic shock involves resuscitation to below normotensive blood pressures achieving the minimum perfusion pressure that will adequately perfuse vital organs until definitive arrest of haemorrhage. AIM: To summarise the evidence for the use of hypotensive resuscitation in patients with uncontrolled haemorrhagic shock and ruptured abdominal aortic aneurysm (AAA). METHODS: A MEDLINE (1966-2004) and Cochrane library search for articles relating to hypotensive resuscitation was undertaken; see text for further details. RESULTS: Several animal studies exist using an abdominal aortotomy model of ruptured AAA. These have demonstrated improved tissue perfusion, decreased blood loss and improved survival associated with hypotensive resuscitation compared with aggressive resuscitation. There are several human studies advocating delayed rather than immediate resuscitation in trauma patients but careful review of the literature reveals no prospective studies of hypotensive resuscitation in patients with ruptured AAA. CONCLUSIONS: Animal studies demonstrate superiority of hypotensive resuscitation over aggressive resuscitation but further research is required to assess its efficacy in patients with ruptured AAA.     

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.     

Two patients with horseshoe kidney and ruptured abdominal aortic aneurysm

Renal anomalies present a challenge to surgeons who repair aortic aneurysms; horseshoe kidneys occur in 1 out of 400 people in the general population. The degree of fusion, accessory blood supply and ureteric anomalies all affect the approach to aneurysm repair in the elective or emergency setting. The authors report two patients with ruptured abdominal aortic aneurysms, who were found at operation to have a horseshoe kidney. In both cases a thick renal isthmus was found crossing the aorta between the inferior mesenteric artery and the bifurcation. The kidney was preserved intact, accessory blood supply was controlled from inside the aorta and the aneurysm was repaired with a Dacron graft. One patient underwent ureterolysis; although renal failure subsequently developed, it was likely related to prolonged preoperative hypotension. The other patient recovered without complications.