Ruptured AAA: open surgical management

Renoprotective potential of exogen erythropoietin on experimental ruptured abdominal aortic aneurysm model: An animal study

Objective(s):

The aim of this study is to investigate the renoprotective effect of erythropoietin (EPO) on hypovolemic shock and ischemia/reperfusion (IR) injury on kidneys as end-organs in an experimentally-created ruptured abdominal aortic aneurysm (rAAA) model.

Materials and Methods:

Thirty anesthetized Sprague-Dawley male rats were randomized to sham ((Sh n:6) (Sh+EPO n:6)) or shock and I/R groups ((S/IR n:9) (S/IR+EPO n:9)). Additional surgical procedure except aortic exploration was not performed on Sh and Sh+EPO groups. 60 min of shock, 60 min of ischemia, and 120 min of reperfusion were applied on S/IR and S/IR+EPO groups. In the S/IR and S/IR+EPO groups, hemorrhagic shock, lower torso ischemia, and reperfusion were created. At the end of the shock period, saline solutions were separately and equally administered to Sh and S/IR groups, whereas 2000 U/kg EPO was intraperitoneally administered to Sh+EPO and S/IR+EPO groups. At the end of the experimental study, some biochemical and histological parameters were studied in serum and kidney tissues.

Results:

Biochemical parameters were all significantly increased in the S/IR group compared with the Sh group. These parameters were not statistically significantly different between S/IR+EPO and Sh+EPO groups. In histopathologic examination, EPO prevented high-grade injury.

Conclusion:

Our data indicate that EPO may have a renoprotective effect and reduce the systemic inflammatory response that resulted from shock and I/R in an experimental model of rAAA.

Current treatment strategies for ruptured abdominal aortic aneurysm

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) represents one of the most challenging emergencies in surgery. Open repair (OR) is associated with relevant morbidity and mortality and has not been reduced significantly over the last decade. The introduction of endovascular aneurysm repair (EVAR) and its meanwhile common use in the treatment of rAAA has raised the demand for randomised controlled trials (RCTs) in order to resolve a potential superiority of either OR or EVAR.

PURPOSE

This review discusses the current treatment strategies in rAAA repair including diagnostics, peri-operative management and results of OR and EVAR, focussing on RCTs comparing both modalities.

RESULTS

Thirty-day mortality after OR and EVAR shows no significant difference in published RCTs. In particular with respect to OR, 30-day mortality was much lower than anticipated throughout all RCTs ranging from 18 to 37 %. EVAR for rAAA resulted in reduced in-hospital stay. Limitations of all except one RCT are low patient recruitment and exclusion of haemodynamically unstable patients.

CONCLUSIONS

OR and EVAR need to be provided for rAAA. Despite lacking evidence, EVAR is the first choice treatment in experienced high-volume vascular centres. Low mortality rates in all RCTs raise the question if aortic surgery should be centralised.

Trace elements in the wall of abdominal aortic aneurysms with and without coexisting iliac artery aneurysms

Iliac artery aneurysms (IAA) and abdominal aortic aneurysms (AAA) frequently coexist. It remains unknown whether the content of trace elements in AAA walls depends on the coexistence of IAAs. The aim of this study was to compare the content of selected trace elements in AAA walls depending on the coexistence of IAAs. The content of trace elements was assessed in samples of AAA walls harvested intraoperatively in 19 consecutive patients. In the studied group, coexisting IAAs were diagnosed in 11 out of the 19 patients with AAA. The coexistence of IAAs was associated with a slightly lower content of nickel (0.28 (0.15-0.40) vs. 0.32 (0-0.85) mg/g; p = 0.09) and a significantly higher content of cadmium (0.71 (0.26-1.17) vs. 0.25 (0.20-0.31) mg/g; p = 0.04) in AAA walls. The levels of the remaining studied elements, copper, zinc, manganese, magnesium and calcium, were comparable. The elevated levels of cadmium in the walls of AAA coexisting with IAAs may suggest an impact of the accumulation of this trace element on the greater damage of the iliac artery wall.

General considerations of ruptured abdominal aortic aneurysm: ruptured abdominal aortic aneurysm

Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair.

Role of ethyl pyruvate in systemic inflammatory response and lung injury in an experimental model of ruptured abdominal aortic aneurysm

Objectıve. The purpose of this study is to evaluate the effect of ethyl pyruvate (EP) on systemic inflammatory response and lung injury in an experimental rat model of ruptured abdominal aortic anurysm (RAAA). Methods. Anaesthetized 30 Sprague-Dawley male rats were randomized to sham (Sh n : 6) (Sh + EP n : 6) or shock and clamp (S/C) groups (S/C n : 9) (S/C + EP n : 9). In the S/C and S/C + EP groups, hemorrhagic shock, lower torso ischemia, and reperfusion were created, S/C group was given 1 mL saline and S/C + EP group was given 40 mg/kg EP. At the end of reperfusion process some biochemical and histological parameters were studied in serum and lung tissues. Results. An increase was observed in all parameters except interleukin-6 (IL-6) in the S/C group in comparison to the sham groups. In the S/C + EP group, serum myeloperoxydase (MPO), malondialdehyde (MDA), and tumor necrosis factor alpha (TNF-α) as well as lung MPO and MDA values decreased significantly (P < 0.016). In the lung tissues, histological injury scores and lung tissue wet/dry ratio were significantly decreased in the S/C + EP group as compared to the S/C group (P < 0.016). Conclusions. Ethyl pyruvate may reduce systemic inflammatory response and lung injury which resulted from shock and ischemia/reperfusion in an experimental model of RAAA.

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.