Predictors for Outcome after Open and Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

The Impact of Heparin on Mortality Following Open Ruptured Abdominal Aortic Aneurysm Repair

BACKGROUND

Systemic administration of heparin is widely used in patients undergoing open elective abdominal aortic aneurysm (AAA) repair. However, no clear consensus exists in the use of intraoperative heparin during open ruptured AAA (rAAA) repair. In this study, we assessed the safety of intravenous heparin administration in patients undergoing open rAAA repair.

METHODS

A retrospective cohort study comparing patients who received and did not receive heparin during open rAAA repair in the Vascular Quality Initiative database between 2003 and 2020 was conducted. The primary outcomes were 30-day and 10-year mortality. The secondary outcomes included estimated blood loss, number of packed red blood cells transfused, early postoperative transfusions, and postsurgical complications. Propensity score matching was used to adjust for potentially confounding variables. The outcomes were compared between the 2 groups using relative risk for binary outcomes and paired t-test and the Wilcoxon rank-sum test for normally and non-normally distributed continuous variables, respectively. Survival was examined using Kaplan-Meier curves and compared using a Cox proportional hazards model.

RESULTS

A total of 2,410 patients who underwent open rAAA repair between 2003 and 2020 were studied. Of the 2,410 patients, 1,853 patients received intraoperative heparin and 557 did not. Propensity score matching on 25 variables yielded 519 pairs for the heparin to no heparin comparison. Thirty-day mortality was lower in the heparin group (risk ratio: 0.74; 95% confidence interval [CI]: 0.66-0.84) and in-hospital was also lower in the heparin group (risk ratio: 0.68; 95% CI: 0.60-0.77). Furthermore, estimated blood loss was 910 mL (95% CI: 230 mL to 1,590 mL) lower in the heparin group and the mean number of packed red blood cells transfused intraoperatively and postoperatively were 17 units lower in the heparin group (95% CI: 8-42). Ten-year survival was higher for patients who received heparin, and their rate of survival was approximately 40% higher than those who did not receive heparin (hazard ratio: 0.62; 95% CI, 0.53-0.72; P < 0.0001).

CONCLUSIONS

In patients who received systemic heparin administration at the time of open rAAA repair, there were significant short-term and long-term survival benefits within 30 days and at 10 years. Heparin administration may have afforded a mortality benefit or been a surrogate for healthier and less moribund patients at the time of the procedure.

Time-to-event data meta-analysis of late outcomes of endovascular versus open repair for ruptured abdominal aortic aneurysms

OBJECTIVE

We investigated whether the well-documented perioperative survival advantage of emergency endovascular aneurysm repair (EVAR) compared with open repair would be sustained during follow-up.

METHODS

A systematic review conforming to the PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement standards was conducted to identify studies that had reported the follow-up outcomes of endovascular vs open repair for ruptured abdominal aortic aneurysms. Electronic bibliographic sources (MEDLINE [medical literature analysis and retrieval system online], Embase [Excerpta Medica database], CINAHL [cumulative index to nursing and allied health literature], and CENTRAL [Cochrane central register of controlled trials]) were interrogated using the Healthcare Databases Advanced Search interface (National Institute for Health and Care Excellence, London, United Kingdom). A time-to-event data meta-analysis was performed using the inverse variance method, and the results were reported as summary hazard ratios (HRs) and associated 95% confidence intervals (CIs). Mixed effects regression was applied to investigate the outcome changes over time. The quality of the body of evidence was appraised using the GRADE (grades of recommendation, assessment, development, and evaluation) system.

RESULTS

Three randomized controlled trials and 22 observational studies reporting a total of 31,383 patients were included in the quantitative synthesis. The mean follow-up duration across the studies ranged from 232 days to 4.9 years. The overall all-cause mortality was significantly lower after EVAR than after open repair (HR, 0.79; 95% CI, 0.73-0.86). However, the postdischarge all-cause mortality was not significantly different (HR, 1.10; 95% CI, 0.85-1.43). The aneurysm-related mortality, which was reported by one randomized controlled trial, was not significantly different between EVAR and open repair (HR, 0.89; 95% CI, 0.69-1.15). Meta-regression showed the mortality difference in favor of EVAR was more pronounced in more recent studies (P = .069) and recently treated patients (P = .062). The certainty for the body of evidence for overall and postdischarge all-cause mortality was judged to be low and that for aneurysm-related mortality to be high.

CONCLUSIONS

EVAR showed a sustained mortality benefit during follow-up compared with open repair. A wider adoption of an endovascular-first strategy is justified.

Abdominal compartment syndrome after r-EVAR: a systematic review with meta-analysis on incidence and mortality

INTRODUCTION

Endovascular aneurysm repair for ruptured abdominal aortic aneurysms (r-EVAR) sometimes complicates with abdominal compartment syndrome (ACS) due to extensive retroperitoneal hematoma, with significant prognostic implications. This systematic review aimed to analyze the incidence of the syndrome and assess the impact of ACS on mortality. Mortality after decompressive laparotomy was also assessed.

EVIDENCE ACQUISITION

Two databases were searched: Medline and Web of Science. The search was conducted through October 2019. The titles and abstracts of the retrieved articles were independently reviewed. All studies reporting on the ACS incidence after r-EVAR were initially included. From each study, eligibility was determined and descriptive, methodological, and outcome data was extracted. The incidence was calculated with summary proportion. Odds ratio was used to compare the mortality rate. Meta-analysis was performed with fixed effect model when calculating the ACS incidence in r-EVAR patients and when assessing the impacts of ACS and DL in the mortality rate.

EVIDENCE SYNTHESIS

A total of 46 studies were included, with a cumulative cohort of 3064 patients. Two hundred and fifty-two (8.2%) patients developed ACS. The ACS pooled incidence was 9% with a 95% confidence interval of [0.08; 0.11]. Among the 46 included studies, 19 studies reported data on the mortality rate, corresponding to 1825 of the 3064 patients. Of these, 169 (9.3%) had developed ACS and 94 (55.6%) of them died by multi organ failure. Among the 1656 patients without ACS, 328 died (19.8%). The mortality odds ratio meta-analysis was 6.25 with a 95% confidence interval of [4.44, 8.80]. Decompressive laparotomy was performed in 41 patients, decreasing mortality in 47%.

CONCLUSIONS

ACS affects approximately 9% of patients submitted to r-EVAR, and significantly increases perioperative mortality. Close postoperative surveillance to clinical signs of ACS is vital in these patients.

Anthropomorphic and biomechanical mockup for abdominal aortic aneurysm

Abdominal aortic aneurysm (AAA) is an asymptomatic condition due to the dilation of abdominal aorta along with progressive wall degeneration, where rupture of AAA is life-threatening. Failures of AAA endovascular repair (EVAR) reflect our inadequate knowledge about the complex interaction between the aortic wall and medical devices. In this regard, we are presenting a hydrogel-based anthropomorphic mockup (AMM) to better understand the biomechanical constraints during EVAR. By adjusting the cryogenic treatments, we tailored the hydrogel to mimic the mechanical behavior of human AAA wall, thrombus and abdominal fat. A specific molding sequence and a pressurizing system were designed to reproduce the geometrical and diseased characteristics of AAA. A mechanically, anatomically and pathologically realistic AMM for AAA was developed for the first time, EVAR experiments were then performed with and without the surrounding fat. Substantial displacements of the aortic centerlines and vessel expansion were observed in the case without surrounding fat, revealing an essential framework created by the surrounding fat to account for the interactions with medical devices. In conclusion, the importance to consider surrounding tissue for the global deformation of AAA during EVAR was highlighted. Furthermore, potential use of this AMM for medical training was also suggested.

Systematic review and meta-analysis of the risk of bowel ischemia after ruptured abdominal aortic aneurysm repair

OBJECTIVE

Outcomes after repair of ruptured abdominal aortic aneurysm (RAAA) have improved in the last decade. It is unknown whether this has resulted in a reduction of postoperative bowel ischemia (BI). The primary objective was to determine BI prevalence after RAAA repair. Secondary objectives were to determine its major sequelae and differences between open repair (OR) and endovascular aneurysm repair (EVAR).

METHODS

This systematic review (PROSPERO CRD42017055920) followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. MEDLINE and Embase were searched for studies published from 2005 until 2018. The methodologic quality of observational studies was assessed with the Methodological Index for Non-Randomized Studies (MINORS) tool. The quality of the randomized controlled trials (RCTs) was assessed with the Cochrane Collaboration's tool for assessing risk of bias. BI prevalence and rates of BI as cause of death, reoperation, and bowel resection were estimated with meta-analyses with a random-effects model. Differences between OR and EVAR were estimated with pooled risk ratios with 95% confidence intervals (CIs). Changes over time were assessed with Spearman rank test (ρ). Publication bias was assessed with a funnel plot analysis.

RESULTS

A total of 101 studies with 52,670 patients were included; 72 studies were retrospective cohort studies, 14 studies were prospective cohort studies, 12 studies were retrospective administrative database studies, and 3 studies were RCTs. The overall methodologic quality of the RCTs was high, but that of observational studies was low. The pooled prevalence of BI ranged from of 0.08 (95% CI, 0.07-0.09) in database studies to 0.10 (95% CI, 0.08-0.12) in cohort studies. The risk of BI was higher after OR than after EVAR (risk ratio, 1.79; 95% CI, 1.25-2.57). The pooled rate of BI as cause of death was 0.04 (95% CI, 0.03-0.05), and that of BI as cause of reoperation and bowel resection ranged between 0.05 and 0.07. BI prevalence did not change over time (ρ, -0.01; P = .93). The funnel plot analysis was highly suggestive of publication bias.

CONCLUSIONS

The prevalence of clinically relevant BI after RAAA repair is approximately 10%. Approximately 5% of patients undergoing RAAA repair suffer from severe consequences of BI. BI is less prevalent after EVAR than after OR.

Abdominal compartment syndrome and ruptured aortic aneurysm: Validation of a predictive test (SCA-AAR)

BACKGROUND

The abdominal compartment syndrome (ACS) has been clearly identified as being one of the main causes of mortality after ruptured abdominal aortic aneurysm (rAAA). The ACS is defined as a sustained intra-abdominal pressure > 20 mm Hg associated with a new organ dysfunction or failure. A pilot study was conducted and found that the threshold of 3 among 8 selected criteria, we would predict an ACS occurrence with a 54% positive predictive value and a 92% negative predictive value. But a multicentric prospective study was clearly needed to confirm these results. The outcome of this new study is to assess the qualities of a predictive test on occurrence of the ACS after rAAA surgery.

METHODS

This is a 30 months prospective cohort study conducted in 12 centers and 165 patients will be included. All patients with a rAAA will be consecutively included, whatever the surgical treatment. At the end of surgery, all patients have an abdominal closure and a monitoring of intrabladder pressure will be established every 3 to 4 hours. Decompressive laparotomy will be indicated when ACS occurs. Follow-up period is 1 month. Eight pre- and per-operative criteria will be studied: anemia, hypotension, cardiac arrest, obesity, massive fluid resuscitation, transfusion, hypothermia, and acidosis.

DISCUSSION

In the literature, there is no recommendation about prophylactic decompression, but early decompressive laparotomy appears to improve survival. This study should make it possible to establish a predictive test, detect the ACS early, and consider a prophylactic decompression in the operating room.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02859662, Registered on 4 August 2016.

Endovascular repair versus open repair in the treatment of ruptured aortic aneurysms: a systematic review

INTRODUCTION

Rupture of abdominal aortic aneurysm remains a fatal event in up to 65% of cases and emergency open surgery (ruptured open aneurysm repair or rOAR) has a great intraoperative mortality of about 30-50%. The introduction of endovascular repair of abdominal aortic aneurysm (ruptured endovascular aneurysm repair or rEVAR) has rapidly challenged the conventional approach to this catastrophic event. The purpose of this systematic review is to compare the outcomes of open surgical repair and endovascular interventions.

EVIDENCE ACQUISITION

A literature search was performed using Medline, Scopus, and Science Direct from August 2010 to March 2017 using keywords identified and agreed by the authors. Randomized trials, cohort studies, and case-report series were contemplated to give a breadth of clinical data.

EVIDENCE SYNTHESIS

Ninety-three studies were included in the final analysis. Thirty-five (50.7%) of the listed studies evaluating the within 30 days mortality rates deposed in favor of rEVAR, while the others (comprising all four included RCTs) failed detecting any difference. Late mortality rates were found to be lower in rEVAR group in seven on twenty-seven studies (25.9%), while one (3.7%) reported higher mortality rates following rEVAR performed before 2005, one found lower incidence of mortality at 6 months in the endovascular group but higher rates in the same population at 8 years of follow-up, and the remaining (66.7%) (including all three RCTs) failed finding any benefit of rEVAR on rOAR. A lower incidence of complications was reported by thirteen groups (46.4%), while other thirteen studies did not find any difference between rEVAR and rOAR. Each of these two conclusions was corroborated by one RCTs. Other two studies (7.2%) found higher rates of tracheostomies, myocardial infarction, and acute tubular necrosis or respiratory, urinary complications, and acute renal failure respectively in rOAR group. The majority of studies (59.0%, 72.7%, and 89.3%, respectively) and all RCTs found significantly lower rates of length of hospitalization, intensive care unit transfer, and blood loss with or without transfusion need in rEVAR group. The large majority of the studies did not specified neither the type nor the brands of employed stent grafts.

CONCLUSIONS

The bulk of evidence regarding the comparison between endovascular and open surgery approach to RAAA points to: 1) non-inferiority of rEVAR in terms of early (within 30 days) and late mortality as well as rate of complications and length of hospitalization, with trends of better outcomes associated to the endovascular approach; 2) significantly better outcomes in terms of intensive care unit transfer and blood loss with or without transfusion need in the rEVAR group. These conclusions reflect the results of the available RCTs included in the present review. Thus rEVAR can be considered a safe method in treating RAAA and we suggest that it should be preferred when technically feasible. However, more RCTs are needed in order to give strength of these evidences, bring to definite clinical recommendations regarding this subject, and assess the superiority (if present) of one or more brands of stent grafts over the others.

Postoperative Development of Abdominal Compartment Syndrome among Patients Undergoing Endovascular Aortic Repair for Ruptured Abdominal Aortic Aneurysms

BACKGROUND

Abdominal compartment syndrome (ACS) has a reported incidence of 9%-14% among trauma patients. However, in patients with similar hemodynamic changes, the incidence of ACS remains unclear. Our aim was to determine the incidence of ACS among patients undergoing endovascular aortic repair (EVAR) for ruptured abdominal aortic aneurysms (rAAAs) and to identify associated risk factors.

METHODS

A retrospective review was performed for consecutive patients who underwent EVAR for rAAA from March 2010 to November 2016 at our institution. The development of ACS was diagnosed based on a variety of factors, including bladder pressure, laboratory abnormalities, hemodynamic monitoring, and clinical evaluation. Previously validated risk factors for ACS development in trauma and EVAR patients (preoperative hypotension, aggressive fluid resuscitation, postoperative anemia, use of an aorto-uniiliac graft, and placement of an aortic occlusive balloon) were analyzed. Association between patient characteristics and ACS development was analyzed using the Fisher's exact test.

RESULTS

During the study period, 25 patients had image-confirmed rAAA and underwent emergent EVAR. Mortality rate was 28% (n = 7), and ACS incidence was 12% (n = 3). Of the analyzed risk factors, hypotension on arrival (P = 0.037), transfusion of 3 or more units of packed red blood cells (P = 0.037), and postoperative anemia (P = 0.02) were all significantly associated with postoperative ACS development. In addition, having greater than 3 of the studied risk factors was associated with increased odds of developing ACS (P = 0.015), and having greater than 4 of the studied risk factors showed the strongest association with ACS development (P = 0.0017).

CONCLUSIONS

Overresuscitation should be avoided in patients with rAAA. In addition, patients who present with multiple risk factors for ACS should be monitored very closely with serial bladder pressures and may require decompression laparotomy immediately after EVAR.

Early experiences of endovascular aneurysm repair for ruptured abdominal aortic aneurysms

Purpose

The use of endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysms (r-AAA) is steadily increasing. We report early experiences of EVAR for r-AAA performed in two tertiary referral centers in Korea.

Methods

We retrospectively reviewed r-AAA patients treated by EVAR from May 2013 to December 2017. An EVAR-first strategy for r-AAA was adopted whenever feasible. The demographic information, anatomic characteristics, operative details, postoperative complications with special attention to abdominal compartment syndrome (ACS), and 30-day mortality were collected and analyzed.

Results

We identified 13 patients who underwent EVAR for r-AAA. Mean age was 74.2 years and mean AAA size was 74.2 mm. Two patients underwent cardiopulmonary resuscitation at initial presentation. Bifurcated stent grafts were used in 12 out of 13 cases and physician-modified endografts with fenestrated/chimney techniques were performed in 2 cases with short neck. Successful stent graft deployment was achieved in all cases. Three patients were suspected of having ACS and 2 of them underwent laparotomy for decompression. The 30-day mortality was 7.7% (1 of 13), the only mortality being a patient that refused decompressive laparotomy for suspected ACS.

Conclusion

Despite the small numbers, the outcomes of EVAR for treatment of r-AAA were very promising, even in selected cases with unfavorable anatomy. These outcomes were achieved by a dedicated and well-trained team approach, and by use of high-end angiographic technology. Finally, ACS after EVAR is not uncommon, and requires a high index of suspicion as well as liberal use of decompressive surgery.

Open Abdomen Therapy with Vacuum and Mesh Mediated Fascial Traction After Aortic Repair: an International Multicentre Study

OBJECTIVES

Open abdomen therapy may be necessary to prevent or treat abdominal compartment syndrome (ACS). The aim of the study was to analyse the primary delayed fascial closure (PDFC) rate and complications after open abdomen therapy with vacuum and mesh mediated fascial traction (VACM) after aortic repair and to compare outcomes between those treated with open abdomen after primary versus secondary operation.

METHODS

This was a retrospective cohort, multicentre study in Sweden, Finland, and Norway, including consecutive patients treated with open abdomen and VACM after aortic repair at six vascular centres in 2006-2015. The primary endpoint was PDFC rate.

RESULTS

Among 191 patients, 155 were men. The median age was 71 years (IQR 66-76). Ruptured abdominal aortic aneurysm (RAAA) occurred in 69.1%. Endovascular/hybrid and open repairs were performed in 49 and 142 patients, respectively. The indications for open abdomen were inability to close the abdomen (62%) at primary operation and ACS (80%) at secondary operation. Duration of open abdomen was 11 days (IQR 7-16) in 157 patients alive at open abdomen termination. The PDFC rate was 91.8%. Open abdomen initiated at primary (N=103), compared with secondary operation (N=88), was associated with less severe initial open abdomen status (p=.006), less intestinal ischaemia (p=.002), shorter duration of open abdomen (p=.007), and less renal replacement therapy (RRT, p<.001). In hospital mortality was 39.3%, and after entero-atmospheric fistula (N=9) was 88.9%. Seven developed graft infection within 6 months, 1 year mortality was 28.6%. Intestinal ischaemia (OR 3.71, 95% CI 1.55-8.91), RRT (OR 3.62, 95% CI 1.72-7.65), and age (OR 1.12, 95% CI 1.06-1.12), were independent factors associated with in hospital mortality, but not open abdomen initiated at primary versus secondary operation.

CONCLUSIONS

VACM was associated with a high PDFC rate after prolonged open abdomen therapy following aortic repair. Patient outcomes seemed better when open abdomen was initiated at primary, compared with secondary operation but a selection effect is possible.

How to identify patients at risk of abdominal compartment syndrome after surgical repair of ruptured abdominal aortic aneurysms in the operating room: A pilot study

Objectives Abdominal compartment syndrome (ACS) is poorly identified in surgery for ruptured abdominal aortic aneurysm and an early management is crucial. The aim of this study was to validate how many risk factors were needed to predict ACS. Secondary objectives were to assess its prevalence and the 30-day mortality. Methods All patients operated for ruptured abdominal aortic aneurysm during 5 years were included. An independent committee performed a retrospective diagnosis of ACS. Eight criteria were selected from the literature, and corresponded to pre- and intraoperative period: anemia (hemoglobin lower than 10 g/dL), prolonged shock (systolic blood pressure <90 mmHg more than 18 min), preoperative cardiac arrest, obesity (body mass index > 30), massive fluid resuscitation (≥3500 mL per hour for at least 1 h) and transfusions (>10 units packed blood red cell since the beginning of the treatment), severe hypothermia (≤33℃), acidosis (pH < 7.2). Sensitivity and specificity were assessed for each number of criteria. Results Eight patients were ACS+ and 28 ACS-, with three criteria for ACS+ and 1.5 for ACS- ( p = 0.002). Three criteria among the eight selected criteria have the best cutoff for sensitivity and specificity (75% and 82%) with a positive predictive value of 54% and a negative predictive value of 92%. The prevalence of ACS was 17%. The 30-day mortality in ACS+ tended to be higher than in ACS- ( p = 0.108). Conclusion The present results suggest that patients with an ACS seemed to have higher mortality and the threshold of three factors among eight specific factors is enough to predict this.

Ruptured abdominal aortic aneurysm: Is endovascular aneurysm repair the answer for everybody?

Treatment paradigms for elective repair of asymptomatic abdominal aortic aneurysms (AAA) have evolved during the past 2 decades, with endovascular aneurysm repair as the preferred treatment modality. The patient care strategy for emergent treatment for ruptured AAA is not as straightforward, due in part to surgeon expertise and stent-graft availability at the institution. Although most reports have extrapolated elective endovascular aneurysm repair feasibility data to the ruptured AAA patient and the aneurysm anatomy, these expectations should be interpreted with caution. In the absence of level I evidence, and lack of adequate local hospital resources, endovascular aneurysm repair-first policy might not be feasible for all the patients who present with ruptured AAA.

Endovascular vs. Open Repair for Ruptured Abdominal Aortic Aneurysm

Background

Patients presenting with ruptured abdominal aortic aneurysms are most often treated with open repair despite the fact that endovascular aneurysm repair is a less invasive and widely accepted method with clear benefits for elective aortic aneurysm patients. A debate exists regarding the definitive benefit in endovascular repair for patients with a ruptured abdominal aortic aneurysm. The aim of this literature review was to determine if any trends exist in favor of either open or endovascular repair.

Material/Methods

A literature search was performed using PUBMED, OVID, and Google Scholar databases. The search yielded 64 publications.

Results

Out of 64 publications, 25 were retrospective studies, 12 were population-based, 21 were prospective, 5 were the results of RCTs, and 1 was a case-series. Sixty-one studies reported on early mortality and provided data comparing endovascular repair (rEVAR) and open repair (rOR) for ruptured abdominal aneurysm groups. Twenty-nine of these studies reported that rEVAR has a lower early mortality rate. Late mortality after rEVAR compared to that of rOR was reported in 21 studies for a period of 3 to 60 months. Results of 61.9% of the studies found no difference in late mortality rates between these 2 groups. Thirty-nine publications reported on the incidence of complications. Approximately half of these publications support that the rEVAR group has a lower complication rate and the other half found no difference between the groups. Length of hospital stay has been reported to be shorter for rEVAR in most studies. Blood loss and need for transfusion of either red cells or fresh frozen plasma was consistently lower in the rEVAR group.

Conclusions

Differences between the included publications affect the outcomes. Randomized control trials have not been able to provide clear conclusions. rEVAR can now be considered a safe method of treating rAAA, and is at least equal to the well-established rOR method.

Improved trends in patient survival and decreased major complications after emergency ruptured abdominal aortic aneurysm repair

BACKGROUND

Improved trends in patient survival and decreased major complications after emergency ruptured abdominal aortic aneurysm (AAA) repair. Emergency AAA repair carries a high risk of morbidity and mortality. This study seeks to examine morbidity and mortality trends from the National Surgical Quality Improvement Program (NSQIP) database, and identify potential risk factors.

METHODS

All emergency AAA repairs were identified using the NSQIP database from 2005 to 2011. Univariate analysis (using the Student t, χ(2), and Fisher's exact tests) and multivariate logistic regression was performed to examine trends in mortality and morbidity.

RESULTS

Out of 2761 patients who underwent emergency AAA repair, 321 (11.6%) died within 24 hours of surgery. Of the remaining 2440 patients, 1133 (46.4%) experienced major complications and 459 (18.8%) died during the postoperative period. From 2005 to 2011, there was a significant decrease in patient mortality, particularly in patients who survived the perioperative period (P = .002). Total complications increased overall (P < .0001); however, major complications decreased from 58.7% in 2005 to 42.6% in 2011 (P < .0001) among patients who survived beyond 24 hours. The use of endovascular aortic repair (EVAR) increased over the study period (P < .0001). On multivariate analysis of patients who survived past the initial 24-hour period, advancing age (odds ratio [OR], 1.1; 95% confidence interval [CI], 1.0-1.1), chronic obstructive pulmonary disease (OR, 2.6; 95% CI, 1.7-4.1), dependent functional status (OR, 2.0; 95% CI, 1.2-3.2), and presence of a major complication (OR, 3.1; 95% CI, 2.0-5.0) were significantly associated with death, whereas presence of a senior resident (OR, 0.4; 95% CI, 0.3-0.6) or fellow (OR 0.3; 95% CI, 0.2-0.6) was inversely associated with death. EVAR was not associated with death, but was associated with 30-day complications (OR, 0.5; 95% CI, 0.3-0.6).

CONCLUSIONS

Patient survival has increased from 2005 to 2011 after emergency AAA repair, with a significant improvement particularly in patients who survive past the first 24 hours. EVAR was not associated with mortality, but was protective of 30-day complications. Although the total number of complications increased, the number of major complications decreased over the study period, suggesting that newer techniques and patient care protocols may be improving outcomes.

Ruptured abdominal aortic aneurysm masquerading as isolated hip pain: an unusual presentation

The rupture of an abdominal aortic aneurysm (AAA) is a catastrophic event. Misdiagnosis by first-contact emergency physicians remains a serious concern. Varied and frequently nonspecific presentations lead to erroneous diagnostic impressions and cause significant delays in definitive intervention. We report the case of a 73-year-old man with a ruptured AAA presenting with isolated acute right hip pain without any classical features such as truncal pain or hypotension. Despite major advances in imaging and definitive treatment, a heightened awareness among emergency physicians remains the only effective means of improving detection and thereby survival.

Abdominal compartment syndrome associated with endovascular and open repair of ruptured abdominal aortic aneurysms

BACKGROUND

Abdominal compartment syndrome (ACS) is a known complication of ruptured abdominal aortic aneurysm (rAAA) repair and can occur with either endovascular (EVAR) or open repair. We hypothesize that the underlying mechanism for the development of ACS may differ for patients treated with EVAR or open operation.

METHODS

All patients who presented with rAAA at a tertiary care medical center between January 2005 and December 2010 were included in the study. Demographic factors, type of repair (open vs EVAR), development of ACS, intraoperative and postoperative fluid requirements, estimated blood loss, length of stay, and morbidity and mortality were recorded. Student t-test and Fisher exact test were performed. A P value < .05 was considered significant.

RESULTS

Seventy-three patients, 62 men and 11 women with an average age of 70.5 years, were treated for rAAA. Forty-four (60%) underwent open repair; 29 (40%) had EVAR. Overall mortality was 42% (31 of 73), with mortality being 31% (9 of 29) in EVAR and 48% (21 of 44) in open repair. ACS developed in 21 patients (29%), more frequently in open repair than in EVAR (15 of 44 [34%] vs 6 of 29 [21%]; P = NS). Mortality was higher in patients who developed ACS compared with those without ACS (13 of 21 [62%] vs 17 of 52 [33%]; P = .022). This finding was especially pronounced in the EVAR group, in which mortality in patients with ACS was 83% (5 of 6) compared with 17% (4 of 23) without ACS (P = .005). Intraoperative fluid requirements were significantly higher in EVAR patients who developed ACS compared with those without ACS, including packed red blood cells (5600 mL vs 1100 mL; P < .0001), total blood products (9300 mL vs 1500 mL; P < .001), crystalloid (11,200 mL vs 4500 mL; P < .001), and estimated blood loss (5000 mL vs 660 mL; P = .006). In patients treated with open repair, there were no significant differences in intraoperative fluid requirements between those who developed ACS and those without ACS. However, patients who developed ACS after open repair required significantly more crystalloid on the first and second postoperative days (first postoperative day, 8300 mL vs 5600 mL [P = .01]; second postoperative day, 6500 mL vs 3800 mL [P = .004]).

CONCLUSIONS

This study demonstrates that the development of ACS after repair of rAAA is associated with increased mortality, especially in EVAR-treated patients. The higher intraoperative blood and blood product requirements associated with ACS in EVAR patients suggest that one potential cause of early ACS is continued hemorrhage from lumbar and inferior mesenteric vessels through the ruptured aneurysm sac. Hence, open ligation of such vessels should be considered in patients developing early ACS after EVAR for rAAA.

Outcome and complications after intra-arterial thrombolysis for lower limb ischaemia with or without continuous heparin infusion

Background

Thrombolysis is a common treatment for acute leg ischaemia. The purpose of this study was to evaluate different thrombolytic treatment strategies, and risk factors for complications.

Methods

This was a retrospective analysis of prospective databases from two vascular centres. One centre used a higher dose of heparin and recombinant tissue plasminogen activator (rtPA).

Results

Some 749 procedures in 644 patients of median age 73 years were studied; 353 (47·1 per cent) of the procedures were done in women. The aetiology of ischaemia was graft occlusion in 38·8 per cent, acute arterial thrombosis in 32·2 per cent, embolus in 22·3 per cent and popliteal aneurysm in 6·7 per cent. Concomitant heparin infusion was used in 63·2 per cent. The mean dose of rtPA administered was 21·0 mg, with a mean duration of 25·2 h. Technical success was achieved in 80·2 per cent. Major amputation and death within 30 days occurred in 13·1 and 4·4 per cent respectively. Bleeding complications occurred in 227 treatments (30·3 per cent). Blood transfusion was needed in 104 (13·9 per cent). Three patients (0·4 per cent of procedures) had intracranial bleeding; all were fatal. Amputation-free survival was 83·6 per cent at 30 days at both centres. In multivariable analysis, preoperative severe ischaemia with motor deficit was the only independent risk factor for major bleeding (odds ratio (OR) 2·98; P <0·001). Independent risk factors for fasciotomy were severe ischaemia (OR 2·94) and centre (OR 6·50). Embolic occlusion was protective for major amputation at less than 30 days (OR 0·30; P = 0·003). Independent risk factors for death within 30 days were cerebrovascular disease (OR 3·82) and renal insufficiency (OR 3·86).

Conclusion

Both treatment strategies were successful in achieving revascularization with acceptable complication rates. Continuous heparin infusion during intra-arterial thrombolysis appeared to offer no advantage.

Effect of regional cooperation on outcomes from ruptured abdominal aortic aneurysm

BACKGROUND

Care for patients with a ruptured abdominal aortic aneurysm (rAAA) in the Amsterdam ambulance region (The Netherlands) was concentrated into vascular centres with a 24-h full emergency vascular service in cooperation with seven referring regional hospitals. Previous population-based survival after rAAA in the Netherlands was 46 (95 per cent confidence interval (c.i.) 43 to 49) per cent. It was hypothesized that regional cooperation would improve survival.

METHODS

This was a prospective observational cohort study carried out simultaneously with the Amsterdam Acute Aneurysm Trial. Consecutive patients with an rAAA between 2004 and 2011 in all ten hospitals in the Amsterdam region were included. The primary outcome was 30-day survival after admission. Multivariable logistic regression, including age, sex, co-morbidity, intervention (endovascular or open repair), preoperative systolic blood pressure, cardiopulmonary resuscitation and year of intervention, was used to assess the influence of hospital setting on survival.

RESULTS

Of 453 patients with rAAA from the Amsterdam ambulance region, 61 did not undergo intervention; 352 patients were treated surgically at a vascular centre and 40 at a referring hospital. The regional survival rate was 58.5 (95 per cent c.i. 53.9 to 62.9) per cent (265 of 453). After multivariable adjustment, patients treated at a vascular centre had a higher survival rate than patients treated surgically at a referring hospital (adjusted odds ratio 3.18, 95 per cent c.i. 1.43 to 7.04).

CONCLUSION

After regional cooperation, overall survival of patients with an rAAA improved. Most patients were treated in a vascular centre and in these patients survival rates were optimal.

Multicenter audit of emergency endovascular repair of infrarenal aortic aneurysms

BACKGROUND

Emergency endovascular aneurysm repair (eEVAR) for infrarenal abdominal aortic aneurysm has become widely accepted as an alternative to open repair, if the aortic anatomy is favorable and endovascular expertise is readily available. The aim of this study is to report the outcome of eEVAR in Hong Kong.

METHODS

This was a retrospective review of prospectively collected data from Hong Kong Hospital Authority Clinical Data Analysis and Reporting System (CDARS), Clinical Management System (CMS), and departmental prospective computerized databases. Patient demographics, clinical and biochemical parameters, perioperative complications, and outcomes were recorded and analyzed. The independent sample t-test was used for continuous variables and the Fisher's exact test was used for nonparametric variables. Kaplan-Meier analysis was performed for overall survival and survival of subgroups. Binary logistic regression was performed for factors predicting perioperative mortality. SPSS software (version 15.0; SPSS Inc., Chicago, IL) was used for all statistical analyses.

RESULTS

A total of 40 patients (36 men with a mean age of 74.9 ± 1.53 years [range: 52-89 years]) underwent emergency eEVAR between January 2006 and September 2011 in 6 Hospital Authority Hospitals in Hong Kong. All patients were treated using commercially available aortoiliac endografts (including 26 bifurcated and 14 aorto-uniiliac grafts). There was 1 conversion from eEVAR to open repair. Blood loss, operating time, duration of stay in intensive care, and duration of stay in the hospital were 948 ± 495.5 mL, 194 ± 12.7 min, 4.7 ± 1.26 days, and 14.5 ± 2.19 days, respectively. The 7-day, 30-day, and 12-month mortality rates were 15%, 17.5%, and 35%, respectively. Six patients required reintervention on follow-up, and 8 patients died during hospitalization. Cox regression analysis of survival found that hypotension (P = 0.001) and being >76 years of age (P = 0.002) were associated with reduced overall survival. Binary logistic regression found that hypotension is associated with increased 30-day mortality (P = 0.026).

CONCLUSIONS

This audit shows that the results of eEVAR in Hong Kong are comparable to international standards. In the endovascular era, this may be an attractive alternative to emergency open aneurysm repair.

Early and mid-term results of a prospective observational study comparing emergency endovascular aneurysm repair with open surgery in both ruptured and unruptured acute abdominal aortic aneurysms

The aim of the paper is to prospectively describe early and mid-term outcomes for emergency endovascular aneurysm repair (eEVAR) versus open surgery in acute abdominal aortic aneurysms (aAAAs), both unruptured (symptomatic) and ruptured. We enrolled all consecutive patients treated for aAAA at our center between April 2002 and April 2008. The main outcome parameters were 30-day, 6- and 12-month mortality (all-cause and aneurysm-related). Two hundred forty patients were enrolled in the study. In the unruptured aAAA group ( n = 111), 47 (42%) underwent eEVAR. The 30-day, 6- and 12-month mortality rates were 6, 13 and 15% in the eEVAR group versus 11% (NS), 13% (NS) and 16% (NS) in the open group, respectively. In the ruptured aAAA group ( n = 129), 25 (19%) underwent eEVAR (mortality rates: 20, 28 and 36%, respectively) compared with 104 (81%) patients who underwent open surgery (mortality rates: 45% ( P = 0.021), 60% ( P = 0.004) and 63% ( P = 0.014), respectively). In conclusion, the present study showed a reduced 30-day, 6- and 12-month mortality of eEVAR compared with open surgery in all patients with aAAA, mainly due to a lower mortality in the ruptured aAAA group. Late aneurysm-related mortality occurred only in the eEVAR group.

A meta-analysis and metaregression analysis of factors influencing mortality after endovascular repair of ruptured abdominal aortic aneurysms

OBJECTIVE

To determine factors that may influence the perioperative mortality after endovascular repair of ruptured abdominal aortic aneurysms (RAAAs) using metaregression analysis.

METHODS

A meta-analysis of all English-language literature with information on mortality rates after endovascular repair of RAAAs was conducted. A metaregression was subsequently performed to determine the impact on mortality of the following 8 factors: patient age; mid-time study point; anaesthesia; endograft configuration; haemodynamic instability; use of aortic balloon; conversion to open repair; and abdominal compartment syndrome.

RESULTS

The pooled perioperative mortality across the 46 studies (1397 patients) was 24.3% (95% CI: 20.7-28.3%). Of the 8 variables, only bifurcated approach was significantly associated with reduced mortality (p = 0.005). A moderate negative correlation was observed between bifurcated approach and haemodynamic instability (-0.35). There was still a strong association between bifurcated approach and mortality after simultaneously adjusting for haemodynamic instability, indicating that the latter was not a major factor in explaining the observed association.

CONCLUSIONS

Endovascular repair of RAAAs is associated with acceptable mortality rates. Patients having a bifurcated endograft were less likely to die. This may be due to some surgeons opting for a bifurcated approach in patients with better haemodynamic condition. Further studies will be needed to clarify this.

Endovascular treatment of ruptured abdominal aortic aneurysms: aorto-uni-iliac or bifurcated endograft?

PURPOSE

This study evaluated the safety and technical and clinical success rates of positioning endovascular endografts (EG) in ruptured abdominal aneurysms.

MATERIALS AND METHODS

Patients with a ruptured abdominal aortic aneurysm confirmed by contrast-enhanced computed tomography angiography (CTA) were eligible for the analysis. Of 67 patients, 42 (62.7%) were treated with EG. Thirteen patients (30.9%) received an aorto-uni-iliac EG (group A) and 29 a bifurcated EG (group B). Patients were divided for comparative analysis according to the configuration of the EG implanted.

RESULTS

The primary technical success rate was 100%; the primary clinical success rate was 95% (40/42). There were two intraoperative deaths (4.7%) related to intractable shock. No patient required conversion to open repair. Overall, 12 patients (28.5%) died within 30 days. The in-hospital death rate was 30.9% (13/42). Hospital mortality rate was statistically higher in group A; the type of EG and intensive care unit admission were the only independent predictors of hospital mortality.

CONCLUSIONS

In our experience, a higher mortality rate was observed for the aorto-uni-iliac configuration; shock at admission was confirmed as the most important factor for postoperative survival.

Ruptured abdominal aortic aneurysm: Endovascular treatment

Aim

The elective endovascular treatment of abdominal aortic aneurysm (AAA) is nowadays a daily routine practice in selected patients. The traditional treatment of ruptured abdominal aortic aneurysm (rAAA) has a peri-operative mortality of 40–50% that has not changed in the last 20 years. Nowadays, the endovascular repair may reduce mortality, hospitalization and sanitary costs.

Methods

The study included 14 patients affected by AAA who came to the Emergency Department because of hemodynamic shock (nine patients) or back pain (five patients). All patients underwent a CT angiography before surgery. Forty-two percent of the patients presented with shock (systolic pressure ≤70 mm Hg) in the operating room, and they underwent an endovascular aortic repair (EVAR) as an emergency procedure. Five bifurcated endoprotesis and nine uniliac protesis making a femoro-femoral bypass to revascularize the excluded limb were made. Patients underwent a follow up with CT angiography one month and then six months after surgery and if no problems were detected, patients underwent a follow-up every year.

Results

Two cases were immediately converted to open surgery because of failed EVAR. Four patients (28%) died after surgery because of multi-organ failure (MOF). The mean hospitalization was 12 days (range 3–21 days). We observed only one case of first-type endoleak at the 1-month follow up and we successfully treated it with a proximal cuff.

Conclusion

In our experience, the intention-to-treat protocol for rAAA offered acceptable results in terms of mortality rates. Multicenter studies are necessary to establish the role of endovascular treatment in patients with rAAA.

Open surgery in endovascular aneurysm repair era: simplified classification in two risk groups owing to factors affecting mortality in 137 ruptured abdominal aortic aneurysms (RAAAs)

Our objective is to identify in 137 true RAAAs operated consecutively in open surgery: (1) diagnostic therapeutic aspects capable of influencing results, (2) risk classes with different prognosis, (3) any situations where the prognosis is so negative that surgery is not recommended. The relationship of 16 anamnestic, clinical and technical parameters prospectively collected with 30-day mortality was retrospectively evaluated by uni- and multivariate analyses. Thirty-day mortality was 37%. The univariate analysis identified as mortality predictors Hb ≤ 8 g/dl and circulatory shock at hospitalisation, but following the multivariate analysis only circulatory shock was a certainly significant risk-factor. The cumulative effect on mortality of the two parameters identified at univariate analysis translates into a statistically significant difference in mortality between two groups of patients: A (no or just one risk-factor) and B (two risk-factors). To reinstate euvolemia, rather than adequate haemoglobin values, improves the chances of success. A simple prognostic index into two risk classes is feasible, but abstention from surgery is not justified in any type of patient.

Early Mortality Following Endovascular Versus Open Repair of Ruptured Abdominal Aortic Aneurysms

Purpose: To determine whether endovascular repair (EVAR) offers a survival advantage over open repair (OAR) with ruptured abdominal aortic aneurysms (RAAA). Methods: Retrospective analysis of RAAA patients treated between 2003 and 2008. Univariate and multivariate analyses were performed. Results: 167 patients presented with RAAA (OAR = 135, 80.8%, EVAR = 32, 19.2%). On univariate analysis, EVAR was associated with a decreased mortality relative to OAR, (15.6% vs 43.7%, P = .004). Patients who survived were younger (P < .0005), had a higher blood pressure (P < .0005), level of consciousness (P < .0005), and hemoglobin (P = .018), and a lower urea (P = .005) and international normalized ratio (INR; P = .001). On multivariate analysis, type of repair remained an independent predictor of 30-day mortality (OR: 0.121; 95% CI: 0.021-0.682, P = .017). Conclusion: Controlling for preoperative factors, EVAR is an independent predictor of lower 30 day mortality relative to open repair after RAAA. This supports the wider use of endovascular repair in all patients with RAAA.

Epidemiology and prognostic factors in acute superior mesenteric artery occlusion

BACKGROUND

Reports on trends in incidence and mortality of acute superior mesenteric artery (SMA) occlusion and evaluation of prognostic factors in recent years are lacking.

METHODS

Patients with acute SMA occlusion were identified through the in-patient and autopsy registry between 1970 and 1982 (n = 270), 1987 to 1996 (n = 135), and 2000 and 2006 (n = 100) in Malmö, Sweden.

RESULTS

The overall incidence rate decreased from 8.6 to 5.4/100,000 person years and the autopsy rate from 87% to 25% over time. A higher serum creatinine level was associated with a lower probability of undergoing multi-detector row computed tomography with intravenous contrast (MDCTiv) (p = 0.006). Not performing a MDCTiv (odds ratio 4.0; 95% confidence interval [1.0-16.0]) remained as independent prognostic factor for in-hospital mortality. General and vascular surgeons collaborated in 25 out of 61 patients that underwent an intervention, of which 21 (84%) (p < 0.001) survived.

CONCLUSIONS

A close collaboration between radiologists and general and vascular surgeons seems to be most important to lower the mortality in patients with acute SMA occlusion.

Early results after treatment of open abdomen after aortic surgery with mesh traction and vacuum-assisted wound closure

OBJECTIVES

This study aimed to describe the use of vacuum-assisted wound closure (VAWC) and mesh traction to repair an open abdomen after aortic surgery.

DESIGN

Prospective clinical study.

MATERIAL AND METHODS

From October 2006 to April 2009, nine consecutive patients were treated; seven of the patients received laparostomy following abdominal compartment syndrome (ACS), while two wounds were left open initially. The indication for laparostomy was intra-abdominal pressure (IAP) > 20 mmHg or abdominal perfusion pressure (APP) < 60 mmHg and development of organ failure. V.A.C. therapy (KCI, San Antonio, TX, USA) was initiated with the laparostomy, and supplemented with a fascial mesh after 2 days. The wound was then closed stepwise with mesh traction and VAWC.

RESULTS

All wounds could be closed following a median interval of 10.5 (range: 6-19) days after laparostomy. A median of four (range: 2-7) dressing changes were performed. One patient died on the seventh postoperative day. Two other patients died 38 and 50 days after final closure, respectively. Left colonic necrosis was seen in two patients while incisional hernia was observed in two patients. Mean follow-up duration was 17 (range: 2-36) months.

CONCLUSION

VAWC with mesh traction was successful in terms of early delayed primary closure and is a useful tool in the treatment of open abdomen after aortic surgery.

CT angiography followed by endovascular intervention for acute superior mesenteric artery occlusion does not increase risk of contrast-induced renal failure

OBJECTIVES

Acute superior mesenteric artery (SMA) occlusion can be diagnosed in an early phase by computed tomography (CT) angiography, which is also a prerequisite for endovascular intervention. However, the issue of development of postoperative permanent renal failure due to contrast-induced nephropathy has not been evaluated.

DESIGN

Retrospective

MATERIALS

A total of 55 patients with acute SMA occlusion were retrieved from the in-hospital register during a 4-year period between 2005 and 2009.

METHODS

Glomerular filtration rate was calculated as a simplified variant of Modification of Diet in Renal Disease Study Group (MDRD).

RESULTS

Preoperative renal insufficiency was found in 52%; advanced state in one patient. Creatinine was lower (p = 0.018) at discharge (median: 71 micromol L(-1)), compared to admission (median: 76 micromol L(-1)), in the 32 survivors exposed to repeated iodinated contrast media (median: 54.7 g iodine). No patient died due to renal failure or needed dialysis after endovascular intervention. Endovascular intervention was associated with a higher survival rate (p = 0.001).

CONCLUSION

Serious acute contrast-induced nephropathy was not found in patients diagnosed by CT angiography and treated by endovascular procedures for acute SMA occlusion. Elevated serum creatinine levels should not deter the clinician from ordering a CT angiography in patients with suspicion of acute SMA occlusion.

Abdominal compartment syndrome in vascular surgery - A review

Abdominal compartment syndrome is a lethal yet under appreciated complication of vascular surgery. The World Society of Abdominal Compartment Syndrome conference in 2004 culminated recent research to formulate the internationally accepted definitions and promote education, in an attempt to reduce a quoted 82% mortality. The syndrome has a broad aetiology, many of which are pertinent to vascular surgery and particularly to ruptured aortic aneurysms. It is defined as an intra-abdominal pressure greater than 12 mm Hg or an abdominal perfusion pressure less than 60mm Hg, in the presence of end organ dysfunction and ultimately leads to multi-organ failure. The physiological derangements which occur in all major organ systems are generally well documented and an understanding of them paramount to early recognition. Numerous methods have been devised to measure intra-abdominal pressure and ideally, measurements utilising a catheter and pressure transducer should be taken in high risk patients yet very few clinicians have measured it. This is essential for diagnosis and also allows grading of the hypertension as clinical and radiological examination does not provide any conclusive information. Appropriate post operative wound closure has an important role in prevention of the syndrome, which would otherwise be treated by surgical decompression. Negative pressure dressings appear to be most beneficial but further prospective trials are required to clarify this.

Endovascular management of ruptured abdominal aortic aneurysms: an 8-year single-centre experience

We aimed to review our experience with the endovascular treatment of ruptured abdominal aortic aneurysm (RAAA). During an 8-year period, 69 patients with a RAAA presented to our department; 67 underwent assessment by computed axial tomography, and 2 died on arrival before any evaluation was possible. A total of 42 patients (63%) were suitable for stent-grafting, and all but 1 (c-arm failure) proceeded to endovascular repair. Of these, 27 underwent surgery with local anaesthesia; 3 did so under general anaesthesia; and a further 11 procedures were commenced with the patient under local anaesthesia and then converted to general anaesthesia. A total of 28 bifurcated and 14 aorto-uni-iliac stent-grafts were implanted. Aortic occlusion balloons were used in 2 (5%) patients. The in-hospital and the 30-day mortality rates were 36% and 41%, respectively. After surgery, 21 complications were encountered in 17 patients. Two patients required reintervention during their hospital stay (1 type I endoleak and 1 limb occlusion). During the follow-up (median 730 days [range 90 to 580 days]), the 1-year and 5-year cumulative survival probabilities were 53% (SE 7.9%) and 50% (SE 8.0%), respectively. Three reinterventions were necessary during follow-up (2 type I endoleaks and 1 graft occlusion). We conclude that endovascular treatment is feasible in the emergency setting, and the early experience is promising. Whether such an approach is superior to open surgery remains to be determined.

Diagnostic accuracy of plasma biomarkers for intestinal ischaemia

OBJECTIVE

Intestinal ischaemia is a life-threatening condition with high mortality, and the lack of accurate and readily available diagnostic methods often results in delay in diagnosis and treatment. The aim of this study was to investigate the accuracy of different plasma biomarkers in diagnosing intestinal ischaemia.

MATERIAL AND METHODS

Prospective inclusion of patients older than 50 years with acute abdomen admitted to hospital in Karlskrona, Sweden, between 2001 and 2003. Venous blood was sampled prior to any surgery and within 24 h from onset of pain. D-lactate, alpha glutathione S-transferase, intestinal fatty acid binding protein, creatine kinase B, isoenzymes of lactate dehydrogenase (LD) and alkaline liver phosphatase (ALP) were analysed. D-dimer was analysed using four different commercially available test kits.

RESULTS

In-hospital mortalities among patients with (n = 10) and without (n = 61) intestinal ischaemia were 40 % and 3 %, respectively (p = 0.003). D-dimer was associated with intestinal ischaemia (p = 0.001) independently of which assay was used. No patient presenting with a normal D-dimer had intestinal ischaemia. D-dimer >0.9 mg/L had a specificity, sensitivity and accuracy of 82 %, 60 % and 79 %, respectively. Total LD, isoenzymes of LD 1-4 and liver isoenzyme of ALP (ALP liver) were significantly higher in patients with intestinal ischaemia, and accuracies for LD 2 (cut-off 2.3 microkat/L) and ALP liver (cut-off 0.7 microkat/L) were 69 % and 66 %, respectively.

CONCLUSIONS

D-dimer may be used as an exclusion test for intestinal ischaemia, but lacks specificity. The other plasma biomarkers studied had insufficient accuracy for this group of patients. Further studies are needed.

Systemic Administration of Heparin Intraoperatively in Patients Undergoing Open Repair of Leaking Abdominal Aortic Aneurysm May Be Beneficial and Does Not Cause Problems

The aim of this study was to investigate whether intravenous heparin administration was associated with a reduction in perioperative mortality and late distal thrombectomy in patients with ruptured abdominal aortic aneuryms (AAAs). One hundred thirty-one patients had repair of ruptured AAA between January 1999 and January 2004. Sixty-three received heparin according to the consultant's preference at the time of the operation. Data were prospectively collected, and multivariate analysis was performed for independent predictive factors. Thirty-day mortality was 29%. Patients receiving heparin had lower perioperative mortality (16% vs 42%; p = .001). Heparin administration was not associated with increased hemorrhage or transfusion. Multivariate analysis confirmed that heparin administration was independently predictive of survival ( p = .036). Other factors found to reduce survival were age ( p = .023), smoking ( p = .042), and systolic blood pressure (< 100 mmHg) at presentation ( p = .045). Fewer patients had thrombectomy after heparin (8% vs 12%), but this was not statistically significant. Perioperative complications were similar in both groups. The administration of systemic heparin before the clamp is applied to leaking aneurysms does not appear to increase hemorrhage and subsequent mortality and may reduce the need for early thrombectomy.