Identifying patients with AAA with the highest risk following endovascular repair

Locoregional Anesthesia's Association With Reduced Intensive Care Unit Stay After Elective Endovascular Aneurysm Repair: Impact of Temporal Changes in Practice Patterns

BACKGROUND

Elective endovascular aneurysm repair (EVAR) can be performed via local anesthetics and/or regional (epidural or spinal) anesthesia (locoregional [LR]), versus general anesthesia (GA), conferring reduced intensive care unit (ICU) and hospital stays. Current analyses fail to account for temporal changes in vascular practice. Therefore, this study aimed to confirm reductions in ICU and hospital stays among LR patients while accounting for changes in practice patterns.

MATERIALS AND METHODS

Using the Society for Vascular Surgery's Vascular Quality Initiative, elective EVARs from August 2003 to June 2021 were grouped into LR or GA. Outcomes included ICU admission and prolonged hospital stay (>2 d). Procedures were stratified into groups of 2 y periods, and outcomes were analyzed within each time period. Univariable and multivariate analyses were used to assess outcomes.

RESULTS

LR was associated with reduced ICU admissions (22.3% versus 32.1%, P < 0.001) and prolonged hospital stays (14.3% versus 7.9%, P < 0.001) overall. When stratified by year, LR maintained its association with reduced ICU admissions in 2014-2015 (21.8% versus 34.0%, P < 0.001), 2016-2017 (23.6% versus 31.6%, P < 0.001), 2018-2019 (18.5% versus 30.2%, P < 0.001), and 2020-2021 (15.8% versus 28.8%, P < 0.001), although this was highly facility dependent. LR was associated with fewer prolonged hospital stays in 2014-2015 (15.6% versus 20.4%, P = 0.001) and 2016-2017 (13.3% versus 16.6%, P = 0.006) but not after 2017.

CONCLUSIONS

GA and LR have similar rates of prolonged hospital stays after 2017, while LR anesthesia was associated with reduced rates of ICU admissions, although this is facility-dependent, providing a potential avenue for resource preservation in patients suitable for LR.

Factors Associated With Noninfectious Fever After Endovascular Aortic Aneurysm Repair

PURPOSE

The post-endovascular abdominal aortic aneurysm repair (EVAR) inflammatory response, which is very often associated with fever, has been ascribed to a wide range of proinflammatory mediators and operative events. The aim of this study was to evaluate the impact of such factors in the development of fever of noninfectious origin after elective EVAR.

MATERIALS AND METHODS

A retrospective analysis of prospectively collected data of patients treated with standard elective EVAR between February 2017 and December 2020 was undertaken. The database included patients' demographics and comorbidities, as well as laboratory inflammatory markers (white blood cell count, neutrophils, and C-reactive protein [CRP]) and anatomical characteristics (sac diameter, inferior mesenteric artery [IMA] patency and diameter, number of patent lumbar arteries, internal iliac artery [IIA] patency or occlusion). Intraoperative details, such as type of stent graft material and IIA overstenting, were also analyzed. Patients with infectious postoperative complications or previously receiving systemic anti-inflammatory medication were excluded. Statistical analysis was performed by SPSS 22.0 for Windows software (IBM Corp, Armonk, New York).

RESULTS

From 332 patients treated with elective EVAR between 2017 and 2020, 268 patients (all men) were included in the analysis. The mean age was 72.1±7.5 years and the mean aneurysm diameter was 59.1±12.1 mm. Seventeen patients were excluded due to a known infection site. From the study cohort, 114 (42.5%) patients presented with fever. Multivariate regression analysis confirmed that the occlusion of IMA ≥5 mm (p<0.008) and higher CRP (p<0.001) were independent factors associated with postoperative fever. A subanalysis was performed only on patients with patent IMA before EVAR. In the multivariate regression analysis of this subgroup, IMA ≥5 mm (p=0.008), presence of dyslipidemia (p=0.037), and higher CRP (p<0.001) were related to fever.

CONCLUSION

Occlusion of an existing wide (≥5 mm) and patent IMA prior to EVAR may contribute to the development of post-EVAR pyrexia. The CRP is a reliable marker for post-EVAR fever. Further prospective studies are needed to corroborate these findings.

Hospital resource use and costs among abdominal aortic aneurysm repair patients admitted to the intensive care unit

BACKGROUND

Abdominal aortic aneurysm (AAA) repair is associated with significant morbidity and mortality. As a result, many of these patients are monitored postoperatively in the intensive care unit (ICU). However, little is known about resource utilization and costs associated with ICU admission in this population. We sought to evaluate predictors of total costs among patients admitted to the ICU after repair of nonruptured or ruptured AAA.

METHODS

We retrospectively analyzed prospectively collected data (2011-2016) of ICU patients admitted after AAA repair. The primary outcome was total hospital costs. We used elastic net regression to identify pre-ICU admission predictors of hospitalization costs separately for nonruptured and ruptured AAA patients.

RESULTS

We included 552 patients in the analysis. Of these, 440 (79.7%) were admitted after repair of nonruptured AAA, and 112 (20.3%) were admitted after repair of ruptured AAA. The mean age of patients with nonruptured AAA was 74 (standard deviation, 9) years, and the mean age of patients with ruptured AAA was 70 (standard deviation, 8) years. Median total hospital cost (in Canadian dollars) was $21,555 (interquartile range, $17,798-$27,294) for patients with nonruptured AAA and $33,709 (interquartile range, $23,173-$53,913) for patients with ruptured AAA. Among both nonruptured and ruptured AAA patients, increasing age, illness severity, use of endovascular repair, history of chronic obstructive pulmonary disease, and excessive blood loss (≥4000 mL) were associated with increased costs, whereas having an anesthesiologist with vascular subspecialty training was associated with lower costs.

CONCLUSIONS

Patient-, procedure-, and clinician-specific variables are associated with costs in patients admitted to the ICU after repair of AAA. These factors may be considered future targets in initiatives to improve cost-effectiveness in this population.

Development of Postoperative Pneumonia After Endovascular Aortic Aneurysm Repair is Associated with an Increased Length of Intensive Care Unit Stay

Objective

Endovascular aortic aneurysm repair (EVAR) has increasingly replaced open aortic surgery for treatment of abdominal aortic aneurysms (AAA). One of the key advantages of EVAR is the reduced length of intensive care unit (ICU) stay and hospital stay. This study aimed to identify the risk factors associated with increased ICU length of stay (LOS) after EVAR.

Methods

The American College of Surgeons (ACS-NSQIP) database for the year 2013 was used. All patients who underwent EVAR were divided into two groups: ICU LOS <1 day vs. ≥1 day. Preoperative, intraoperative, and postoperative factors were compared between these two groups utilizing bivariate logistic regression analysis. Multivariable logistic regression analysis was then used to identify factors that were independently associated with ICU LOS ≥1 day after EVAR.

Results

A total of 2,468 patients (18.7% females, 81.3% males) were identified. Group 1 (ICU LOS <1 day) = 1,535 patients and Group 2 (ICU LOS ≥1 day) = 933 patients. Multivariable analysis identified the following factors to be associated with ICU LOS ≥1 day: ruptured AAA (OR 3.88, CI 1.97-7.65), the American Society of Anesthesiology (ASA) score of 4-5 (OR 2.82, CI 1.50-5.31), operative time ≥180 minutes (OR 2.10, CI 1.51-2.93), bilateral groin cut down (OR 1.37, CI 1.10-1.71), juxta-renal AAA (OR 1.65, CI 1.16-2.35), renal artery stent (OR 2.13, CI 1.42-3.21), aortic stent (OR 2.39, CI 1.60-3.55), emergency surgery (OR 2.56, CI 1.94-3.38), need for blood transfusion (OR 3.11, CI 2.08-4.65) and postoperative pneumonia (OR 7.04, CI 1.95-25.45).

Conclusion

Variables identified above can be used to predict the cohort of EVAR patients which will likely require ICU for ≥1 day. Development of postoperative pneumonia is associated with a 7.04 times increase in ICU LOS ≥1 day.

Editor's Choice - Prolonged ICU Length of Stay after AAA Repair: Analysis of Time Trends and Long-term Outcome

OBJECTIVE

The aim of the study was to investigate the frequency and outcome of prolonged intensive care unit (ICU) length of stay (LOS) after abdominal aortic aneurysm (AAA) repair in the endovascular era.

METHODS

All patients operated on for AAA between 1999 and 2013 at Uppsala University hospital were identified. Data were retrieved from the Swedish Vascular registry, the Swedish Intensive Care registry, the National Population registry, and case records. Prolonged ICU LOS was defined as ≥ 48 h during the primary hospital stay. Patients surviving ≥ 48 h after AAA surgery were included in the analysis.

RESULTS

A total of 725 patients were identified, of whom 707 (97.5%) survived ≥ 48 h; 563 (79.6%) underwent intact AAA repair and 144 (20.4%) ruptured AAA repair. A total of 548 patients (77.5%) required < 48 h of intensive care, 115 (16.3%) 2-6 days and 44 (6.2%) ≥ 7 days. The rate of prolonged ICU LOS declined considerably over time, from 41.4% of all AAA repairs in 1999 to 7.3% in 2013 (p < .001) whereas the use of endovascular aortic repair (EVAR) increased from 6.9% in 1999 to 78.0% in 2013 (p < .001). The 30 day survival rate was 98.2% for those with < 48 h ICU stay versus 93.0% for 2-6 days versus 81.8% for ≥ 7 days (p < .001); the corresponding 90 day survival was 97.1% versus 86.1% versus 63.6% (p < .001) respectively. For patients surviving 90 days after repair, there was no difference in long-term survival between the groups.

CONCLUSION

During the period of progressively increasing use of EVAR, a simultaneous significant reduction in frequency of prolonged ICU LOS occurred. Although prolonged ICU LOS was associated with a high short-term mortality, long-term outcome among those surviving the initial 90 days was less affected.

Endovascular versus open repair of ruptured abdominal aortic aneurysm

INTRODUCTION

Endovascular aneurysm repair (EVAR) is a comparatively less invasive technique than open repair (OR). Debate remains with regard to the benefit of EVAR for patients with ruptured abdominal aortic aneurysm (RAAA). We sought to evaluate and report outcomes of EVAR for RAAA in an Irish tertiary vascular referral centre.

METHODS

Patients undergoing emergency surgery for ruptured or symptomatic AAA were identified from theatre logbooks and HIPE database. Retrospective chart review was undertaken. Data were exported to IBM SPSS version 21 for statistical analysis with p < 0.05 considered significant.

RESULTS

A total of 41 patients underwent surgery for RAAA. The mean age was 74 years old with a range from 55 to 89 years. The majority (n = 25, 61%) were baseline American Society of Anaesthesiology (ASA) grade 3-4. Of these 56% underwent EVAR with the remaining 44% repaired open. Mortality rate in those undergoing emergency EVAR was 34.8%, compared with 38.9% in those undergoing open surgery. This difference was not statistically significant. The mean overall length of stay was 13 days. With regard to prognostic indicators of patient outcome, increasing patient age was noted to be significantly associated with increased mortality (p = 0.013), as was increased ASA score at time of surgery (p = 0.029).

CONCLUSIONS

Mortality rates in those undergoing EVAR for RAAA are comparable with those undergoing open repair. Increasing age and ASA score are significant predictors of mortality in patients with RAAA undergoing intervention.

Targets to prevent prolonged length of stay after endovascular aortic repair

OBJECTIVE

Endovascular aneurysm repair (EVAR) is a commonly performed vascular operation. Yet, postoperative length of stay (LOS) varies greatly, even within institutions. The present study reviewed the morbidity, mortality, and the financial effect of increased LOS to establish modifiable factors associated with prolonged hospital LOS, with the goal of improving quality.

METHODS

The Society for Vascular Surgery Vascular Quality Initiative database was used to identify all patients undergoing primary, elective EVAR at a single institution between January 1, 2011, and May 28, 2014. Preoperative patient characteristics, intraoperative details, postoperative factors, long-term outcomes, and cost data were reviewed using an Institutional Review Board-approved prospectively collected database. Multivariate analysis was used to determine statistical difference between patients with LOS ≤2 days and >2 days.

RESULTS

Complete 30-day variable and cost data were available for 138 patients with an average follow-up of 12 months; of these, 46 (33%) had a LOS >2 days. Variables determined to be statistically significant predictors of prolonged LOS included aneurysm diameter (P = .03), American Society of Anesthesiologists Physical Status Classification score (P < .001), thromboembolectomy (P = .01), and increased postoperative cardiac (P < .001) and renal (P = .01) complications. Specifically, modifiable risk factors that contributed to increased LOS included performance of a concomitant procedure (P < .001), increased volume of iodinated contrast (P = .05), increased volume of intraoperative crystalloid (P = .05), placement in an intensive care unit (P < .001), return to the operating room (P < .001), and the use of vasoactive medications (P < .001). Hospital charges ($102,000 ± $41,000 vs $180,000 ± $73,000; P = .01) and costs ($27,000 ± $10,000 vs $45,000 ± $19,000 P = .01) were significantly higher in patients with prolonged LOS; however, there was no difference in physician charges ($8000 ± $5700 vs $12,000 ± $12,000; P = .09). Increased LOS after EVAR was associated with an increase in mortality at 1 month (0% vs 4% P = .05) and 12 months (3% vs 13% P = .03).

CONCLUSIONS

This study highlights several modifiable risk factors leading to increased LOS after EVAR, including performance of concomitant procedures, admission to the intensive care unit, and postoperative renal and cardiac complications. Further, increased LOS was associated with increased charges, costs, morbidity, and mortality after EVAR. This study highlights specific areas of focus for decreasing LOS after EVAR and, in turn, improving quality in vascular surgery.