Effect of early plasma transfusion on mortality in patients with ruptured abdominal aortic aneurysm

Increasing Use of Prophylactic Open Abdomen Therapy With Vacuum Assisted Wound Closure and Mesh Mediated Fascial Traction After Repair of Ruptured Abdominal Aortic Aneurysm

OBJECTIVE

Open abdomen therapy (OAT) is commonly used to prevent or treat abdominal compartment syndrome (ACS) in patients with ruptured abdominal aortic aneurysms (rAAAs). This study aimed to evaluate the incidence, treatment, and outcomes of OAT after rAAA from 2006 to 2021. Investigating data on resuscitation fluid, weight gain, and cumulative fluid balance could provide a more systematic approach to determining the timing of safe abdominal closure.

METHODS

This was a single centre observational cohort study. The study included all patients treated for rAAA followed by OAT from October 2006 to December 2021.

RESULTS

Seventy-two of the 244 patients who underwent surgery for rAAA received OAT. The mean age was 72 ± 7.85 years, and most were male (n = 61, 85%). The most frequent comorbidities were cardiac disease (n = 31, 43%) and hypertension (n = 31, 43%). Fifty-two patients (72%) received prophylactic OAT, and 20 received OAT for ACS (28%). There was a 25% mortality rate in the prophylactic OAT group compared with the 50% mortality in those who received OAT for ACS (p = .042). The 58 (81%) patients who survived until closure had a median of 12 (interquartile range [IQR] 9, 16.5) days of OAT and 5 (IQR 4, 7) dressing changes. There was one case of colocutaneous fistula and two cases of graft infection. All 58 patients underwent successful abdominal closure, with 55 (95%) undergoing delayed primary closure. In hospital survival was 85%. Treatment trends over time showed the increased use of prophylactic OAT (p ≤ .001) and fewer ACS cases (p = .03) assessed by Fisher's exact test. In multivariable regression analysis fluid overload and weight reduction predicted 26% of variability in time to closure.

CONCLUSION

Prophylactic OAT after rAAA can be performed safely, with a high rate of delayed primary closure even after long term treatment.

Editor's Choice -- European Society for Vascular Surgery (ESVS) 2024 Clinical Practice Guidelines on the Management of Abdominal Aorto-Iliac Artery Aneurysms

OBJECTIVE

The European Society for Vascular Surgery (ESVS) has developed clinical practice guidelines for the care of patients with aneurysms of the abdominal aorta and iliac arteries in succession to the 2011 and 2019 versions, with the aim of assisting physicians and patients in selecting the best management strategy.

METHODS

The guideline is based on scientific evidence completed with expert opinion on the matter. By summarising and evaluating the best available evidence, recommendations for the evaluation and treatment of patients have been formulated. The recommendations are graded according to a modified European Society of Cardiology grading system, where the strength (class) of each recommendation is graded from I to III and the letters A to C mark the level of evidence.

RESULTS

A total of 160 recommendations have been issued on the following topics: Service standards, including surgical volume and training; Epidemiology, diagnosis, and screening; Management of patients with small abdominal aortic aneurysm (AAA), including surveillance, cardiovascular risk reduction, and indication for repair; Elective AAA repair, including operative risk assessment, open and endovascular repair, and early complications; Ruptured and symptomatic AAA, including peri-operative management, such as permissive hypotension and use of aortic occlusion balloon, open and endovascular repair, and early complications, such as abdominal compartment syndrome and colonic ischaemia; Long term outcome and follow up after AAA repair, including graft infection, endoleaks and follow up routines; Management of complex AAA, including open and endovascular repair; Management of iliac artery aneurysm, including indication for repair and open and endovascular repair; and Miscellaneous aortic problems, including mycotic, inflammatory, and saccular aortic aneurysm. In addition, Shared decision making is being addressed, with supporting information for patients, and Unresolved issues are discussed.

CONCLUSION

The ESVS Clinical Practice Guidelines provide the most comprehensive, up to date, and unbiased advice to clinicians and patients on the management of abdominal aorto-iliac artery aneurysms.

Systematic review of plasma/packed red blood cell ratio on survival in ruptured abdominal aortic aneurysms

BACKGROUND

The ideal perioperative fluid resuscitation for patients with ruptured abdominal aortic aneurysms (rAAAs) is unknown. It has been shown in trauma studies that a higher ratio of plasma and platelets to packed red blood cells confers a mortality benefit. Controversy remains whether this is true also in the rAAA population. The objective of the present study was to investigate the benefit of a greater ratio of plasma/packed red blood cells in patients with rAAAs.

METHODS

A health sciences librarian searched four electronic databases, including PubMed, Embase, Cochrane, and ClinicalTrials.gov, using concepts for the terms "fluid resuscitation," "survival," and "ruptured abdominal aortic aneurysm." Two reviewers independently screened the studies that were identified through the search strategy and read in full any study that was potentially relevant. Studies were included if they had compared the mortality of patients with rAAAs who had received a greater ratio of plasma to other component therapy with that of patients who had received a lower ratio. The risk of bias was assessed using the ROBINS-I (risk of bias in nonrandomized studies of interventions) validated tool, and evidence quality was rated using the GRADE (grades of recommendation assessment, development, and evaluation) profile. No data synthesis or meta-analysis was planned or performed, given the anticipated paucity of research on this topic and the high degree of heterogeneity of available studies.

RESULTS

Our search identified seven observational studies for inclusion in the present review. Of these seven studies, three found an associated decrease in mortality with a greater ratio of plasma to packed red blood cells. The remaining four found no significant differences. The overall risk of bias was serious, and the evidence quality was very low.

CONCLUSIONS

Overall, the findings from the available studies would suggest that for patients who have undergone open surgery for a rAAA, mortality tends to be decreased when the amount of plasma transfused perioperatively is similar to the amount of packed red blood cells. However, the included studies reported very low-quality evidence based solely on highly heterogeneous observational studies, and further research is warranted.

Inverse probability of treatment analysis of open vs endovascular repair in ruptured infrarenal aortic aneurysm - Cohort study

BACKGROUND

To compare open repair (OR) with EVAR for the management of ruptured infrarenal abdominal aortic aneurysms (RAAA) in a cohort study over a time period of 15 years with inverse probability of treatment weights.

MATERIAL AND METHODS

From 2000/01 through 2015/12 136 patients were treated for RAAA, 98 (72.1%) underwent OR, 38 (27.9%) were treated with EVAR. Thirty-day and long-term mortality (survival) were analyzed in this IRB-approved retrospective cohort study. Treatment modalities were compared using inverse probability of treatment weights to adjust for imbalances in demographic data and risk factors.

RESULTS

EVAR patients were older (75.11 ± 7.17 vs 69.79 ± 10.24; p=0.001). There was no statistical difference in gender, hypertension, COPD, CAD, or diabetes. GFR was significantly higher in OR patients (71.4 ± 31.09 vs. 53.68 ± 25.73). Postoperative dialysis was required more frequently in EVAR patients: 11% vs. 2% (p = 0.099). In the OR group, adjusted cumulative survival was 70.4% (61.1, 81.1) at 30 days, 47.0% (37.1, 59.6) at one year and 38.3% (28.6, 51.3) at 5 years. In the EVAR group the corresponding numbers were 77.0% (67.7, 87.5), 67.5% (57.0, 80.0) and 41.7% (30.4, 57.4), respectively.

CONCLUSION

There is evidence for EVAR patients exhibiting a benefit in one-year survival, while patients treated with OR may have more favorable long-term survival given they survive for at least one year. Herein we provide a statistically rigorous comparison of OR and EVAR in short and long-term outcomes with up to 15 years of follow-up.

Feasibility and Safety of Sac Embolization Using N-Butyl Cyanoacrylate in Emergency Endovascular Aneurysm Repair for Ruptured Abdominal Aortic Aneurysms or Isolated Iliac Artery Aneurysms

PURPOSE

To evaluate the feasibility and safety of sac embolization with N-butyl cyanoacrylate (NBCA) in emergency endovascular aneurysm repair (EVAR) for ruptured abdominal aortic aneurysm (AAA) and iliac artery aneurysm (IAA) in comparison to EVAR without sac embolization.

MATERIALS AND METHODS

Between February 2012 and December 2019, among 44 consecutive patients with ruptured AAA or IAA, 29 underwent EVAR. Of these, 22 patients (median age 77.5 years; 18 men) had concomitant sac embolization using NBCA; the remaining 7 patients (median age 88 years; 6 men) underwent EVAR without sac embolization and form the control group. The technical success, clinical success (hemodynamic stabilization), procedure-related complications, and mortality were compared between the groups.

RESULTS

All EVAR procedures and embolizations were successful. The clinical success rates in the NBCA and control groups were 95% (21/22) and 71% (5/7), respectively (p=0.14). There was no complication related to the procedure. Type II endoleak occurred in 4 of 21 patients (19%) in the NBCA group vs none of the control patients. One patient (5%) died in the NBCA group vs 3 (43%) in the controls (p=0.034).

CONCLUSION

Sac embolization using NBCA in emergency EVAR appears to be feasible and safe for ruptured AAA and IAA.

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.

Association Between Ratio of Fresh Frozen Plasma to Red Blood Cells During Massive Transfusion and Survival Among Patients Without Traumatic Injury

Importance

Hemostatic resuscitation has been shown to be beneficial for patients with trauma, but there is little evidence that it is equally beneficial for bleeding patients without trauma. The practice of a high transfusion ratio of fresh frozen plasma (FFP) to red blood cells (RBCs) has spread to other surgical and medical fields.

Objective

To identify whether ratio-based resuscitation in patients without trauma is associated with improved survival.

Design, Setting, and Participants

This study is a retrospective review of all massive transfusions provided in an urban academic hospital from January 1, 2009, through December 31, 2012. Massive transfusion was defined as the transfusion of at least 10 U of RBCs in the first 24 hours after a patient's admission to the operating room, emergency department, or intensive care unit. All patients who received massive transfusions within the study period and survived more than 30 minutes after hospital arrival were counted (n=865). Patients were grouped into those with trauma and those without trauma. Sources of data included the Research Patient Data Registry, patients' medical records, and blood bank records. All data collection occurred between April 26, 2013, and April 26, 2015. Data analysis took place from April 27, 2015, and June 22, 2016.

Main Outcomes and Measures

Examination of FFP:RBC transfusion ratios for patients without trauma.

Results

There were 865 massive transfusion events that occurred within 4 years, transfusing 16 569 U of RBCs, 13 933 U of FFP, 5228 U of cryoprecipitate, and 22 635 U of platelets. Most of these transfusions were received by patients without trauma (767 [88.7%]), by men (582 [67.3%]), and for intraoperative bleeding (544 [62.9%]). The FFP:RBC ratios of survivors and nonsurvivors were nearly identical: the ratio for survivors was 1:1.5 (interquartile range [IQR], 1:1.1-1:2.2) and for nonsurvivors was 1:1.4 (IQR, 1:1.1-1:1.9; P = .43). Among the 767 patients without trauma, there was no difference in the adjusted odds ratio (aOR) for 30-day mortality when comparing the high FFP:RBC ratio vs the low FFP:RBC ratio subgroups (aOR, 1.10; 95% CI, 0.72-1.70; P = .65). In vascular surgery, the aOR for death favored the high FFP:RBC ratio subgroup (aOR, 0.16; 95% CI, 0.03-0.79; P = .02). However, in general surgery and medicine, the aOR for death favored the low FFP:RBC ratio subgroup; general surgery: aOR, 4.27 (95% CI, 1.28-14.22; P = .02); medicine: aOR, 8.48 (95% CI, 1.50-47.75; P = .02).

Conclusions and Relevance

High FFP:RBC transfusion ratios are applied mostly to patients without trauma, who account for nearly 90% of all massive transfusion events. Thirty-day survival was not significantly different in patients who received a high FFP:RBC ratio compared with those who received a low ratio.

Hemorrhage and Transfusions in the Surgical Patient

Hemorrhage remains the leading cause of intra-operative deaths and those in the first 24 h. Many cardiovascular and hepatobiliary procedures result in massive hemorrhage and postpartum hemorrhage events in labor and delivery place the patient at a high risk for mortality. Both upper and lower gastrointestinal bleeding (e.g., diverticulosis, esophageal and gastric varices, and peptic ulcer disease) can also result in significant blood loss requiring massive transfusion and resuscitation from hemorrhagic shock. Therefore, safe, timely, and effective transfusion of blood products is critical. The aim of this chapter is to provide clinicians with a discussion of the current literature on the various blood component products, their indications, and unique hemostatic conditions in the surgical patient. While the majority of data concerning optimal management of acquired coagulopathy and hemorrhagic shock resuscitation is based on trauma patients, many of the principles can and should be applied to the surgical patient (or likely any patient) with profound hemorrhage.

The beneficial place for the treatment of ruptured abdominal aortic aneurysms

OBJECTIVE

To study the beneficial place for the treatment of ruptured abdominal aortic aneurysms (RAAAs).

METHOD

A retrospective chart review of consecutive RAAA patients was performed. Patients were divided into two groups: direct group and transfer group. We retrospectively reviewed patients' hospital charts and recorded various clinical factors apparent on presentation. The primary consequence was mortality during hospitalization, and some other parameters such as duration of intensive care unit (ICU). All patients were followed up at 1 month, 3 months, 6 months and one year after discharge.

RESULTS

During 4-year period, 56 RAAA patients were treated (24 in direct group, and 32 in transfer group). Significant differences were shown for systolic blood pressure, pulse oxygen saturation, hemoglobin, the time interval from diagnosis to operation et al. There was no difference concerning age and comorbidity among two groups. All the patients were treated by open surgical aneurysm repair. The mortality rate was 68.8% ((6 + 16)/32) in transfer group and 33.3% (8/24) in direct group (P = 0.00067). Both the duration of ICU stay and entire hospitalization were a bit longer in the transfer group, but there was no significant difference. The mean follow-up time was 25.2 ± 12.9 months. The cumulative survival difference was significant (P = 0.042) between the two groups.

CONCLUSION

It is beneficial that we treat RAAAs in the diagnosed hospital. The reasons are: 1) to avoid the development of unstable state of aneurysm after rupturing of stable state; 2) the time interval from initial symptoms to operation will be shortened.

Massive Blood Transfusion in Patients with Ruptured Abdominal Aortic Aneurysm

OBJECTIVES

The aim was to study blood transfusions and blood product ratios in massively transfused patients treated for ruptured abdominal aortic aneurysms (rAAAs).

METHODS

This was a registry based cohort study of rAAA patients repaired at three major vascular centres between 2008 and 2013. Data were collected from the Swedish Vascular Registry, hospitals medical records, and local transfusion registries. The transfusion data were analysed for the first 24 h of treatment. Massive transfusion (MT) was defined as 4 or more units of red blood cell (RBC) transfused within 1 h, or 10 or more RBC units within 24 h. Logistic regression was used to calculate the odds ratio of 30 day mortality associated with the ratios of blood products and timing of first units of platelets (PLTs) and fresh frozen plasma (FFP) transfused.

RESULTS

Three hundred sixty nine rAAA patients were included: 80% men; 173 endovascular aneurysm repairs (EVARs) and 196 open repairs (ORs) with median RBC transfusion 8 units (Q1-Q3, 4-14) and 14 units (Q1-Q3, 8-28), respectively. A total of 261 (71%) patients required MT. EVAR patients with MT (n = 96) required less transfusion than OR patients (n = 165): median RBC 10 units (Q1-Q3, 6-16.5) vs. 15 units (Q1-Q3, 9-26) (p = .002), FFP 6 units (Q1-Q3, 2-14.5) vs. 13 units (Q1-Q3, 7-24) (p < .001), and PLT 0 units (Q1-Q3, 0-2) vs. 2 units (Q1-Q3, 0-4) (p = .01). Median blood product ratios in MT patients were FFP/RBC (EVAR group 0.59 [0.33-0.86], OR group 0.84 [0.67-1.2]; p < .001], and PLT/RBC (EVAR 0 [0-0.17], OR 0.12 (0-0.18); p < .001]. In patients repaired by OR a FFP/RBC ratio close to 1 was associated with reduced 30 day mortality (p = .003). The median PLT/RBC ratio was higher during the later part of the study period (p < .001, median test), whereas there was no significant difference in median FFP/RBC ratio (p = .101, median test).

CONCLUSION

The majority of rAAA patients undergoing EVAR required MT. EVAR patients treated with MT had lower FFP/RBC and PLT/RBC ratios than OR patients with MT. The mortality risk was lower with FFP/RBC ratio close to 1:1 in open repaired patients requiring MT. The 24 h PLT/RBC ratio increased over the study period.

The survival impact of plasma to red blood cell ratio in massively transfused non-trauma patients

PURPOSE

High ratios of Plasma to Packed Red Blood Cells (FFP:PRBC) improve survival in massively transfused trauma patients. We hypothesized that non-trauma patients also benefit from this transfusion strategy.

METHODS

Non-trauma patients requiring massive transfusion from November 2003 to September 2011 were reviewed. Logistic regression was performed to identify independent predictors of mortality. The population was stratified using two FFP:PRBC ratio cut-offs (1:2 and 1:3) and adjusted mortality derived.

RESULTS

Over 8 years, 29 % (260/908) of massively transfused surgical patients were non-trauma patients. Mortality decreased with increasing FFP:PRBC ratios (45 % for ratio ≤1:8, 33 % for ratio >1:8 and ≤1:3, 27 % for ratio >1:3 and ≤1:2 and 25 % for ratio >1:2). Increasing FFP:PRBC ratio independently predicted survival (AOR [95 % CI]: 1.91 [1.35-2.71]; p < 0.001). Patients achieving a ratio >1:3 had improved survival (AOR [95 % CI]: 3.24 [1.24-8.47]; p = 0.016).

CONCLUSION

In non-trauma patients undergoing massive transfusion, increasing FFP:PRBC ratio was associated with improved survival. A ratio >1:3 significantly improved survival probability.

Editor's Choice - Abdominal Compartment Syndrome After Surgery for Abdominal Aortic Aneurysm: A Nationwide Population Based Study

OBJECTIVE/BACKGROUND

The understanding of abdominal compartment syndrome (ACS), and its importance for outcome, has increased over time. The aim was to investigate the incidence and clinical consequences of ACS after open (OR) and endovascular repair (EVAR) for ruptured and intact infrarenal abdominal aortic aneurysm (rAAA and iAAA, respectively).

METHODS

In 2008, ACS and decompression laparotomy (DL) were introduced as variables in the Swedish vascular registry (Swedvasc), offering an opportunity to study this complication in a prospective, population based design. Operations carried out in the period 2008-13 were analysed. Of 6,612 operations, 1,341 (20.3%) were for rAAA (72.0% OR) and 5,271 (79.7%) for iAAA (41.9% OR). In all, 3,171 (48.0%) were operated on by OR and 3,441 by EVAR. Prophylactic open abdomen (OA) treatment was validated through case records. Cross-matching with the national population registry secured valid mortality data.

RESULTS

After rAAA repair, ACS developed in 6.8% after OR versus 6.9% after EVAR (p = 1.0). All major complications were more common after ACS (p < .001). Prophylactic OA was performed in 10.7% of patients after OR. For ACS, DL was performed in 77.3% after OR and 84.6% after EVAR (p = .433). The 30 day mortality rate was 42.4% with ACS and 23.5% without ACS (p < .001); at 1 year it was 50.7% versus 31.8% (p < .001). After iAAA repair, ACS developed in 1.6% of patients after OR versus 0.5% after EVAR (p < .001). Among those with ACS, DL was performed in 68.6% after OR and in 25.0% after EVAR (p = .006). Thirty day mortality was 11.5% with ACS versus 1.8% without it (p < .001); at 1 year it was 27.5% versus 6.3% (p < .001). When ACS developed, renal failure, multiple organ failure, intestinal ischaemia, and prolonged intensive care were much more frequent (p < .001). Morbidity and mortality were similar, regardless of primary surgical technique (OR/EVAR/iAAA/rAAA).

CONCLUSION

ACS and OA were common after treatment for rAAA. ACS is a devastating complication after surgery for rAAA and iAAA, irrespective of operative technique, emphasizing the importance of prevention.

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.

Presenting Baseline Coagulation of Infra Renal Ruptured Abdominal Aortic Aneurysm: A Systematic Review and Pooled Analysis

BACKGROUND

The incidence of coagulopathy in patients presenting with rAAA is not clear. The lack of high-quality evidence has led to various speculations, reliance on anecdotal experience, and suggestions about their appropriate haemostatic resuscitation. The aim of this systematic review is to establish the baseline coagulation status of infra renal ruptured abdominal aortic aneurysms (rAAA) against defined standards and definitions.

METHODS

An electronic search of literature in Medline, CINHAL, Scopus Embase, and Cochrane library was performed in accordance with the PRISMA guidelines. Quality assessment of articles was performed using the Oxford critical appraisal skills programme (CASP) and their recommendation for practice was examined through National Institute for Health and Care Excellence (NICE). Information on platelet count, international normalisation ratio (INR), activated partial prothrombin time (aPTT), prothrombin time (PT) fibrinogen and D-dimer was extracted, and pooled analysis was performed in accordance with the definition of coagulopathy and its subtypes. Pooled prevalence of coagulopathies and 95% CI were estimated with a variance weighted random effects model.

RESULTS

Seven studies, comprising 461 patients were included in this systematic review. Overall weighted prevalence of coagulopathy was 12.3% (95% CI 10.7-13.9), 11.7% for INR (95% CI 1-31.6), 10.1% for platelet count (95% CI 1-26.8), and 11.1% for aPTT (95% CI 0.78-31). Fibrinogen serum concentration level was normal in 97%, and 46.2% (n = 55) of patients had elevated D-dimer. Only 6% of the entire population demonstrated significant coagulopathy. DIC was noted in 2.4% of the population.

CONCLUSION

This first systematic review of literature on baseline coagulation of rAAAs suggests that the majority of these patients do not present with coagulopathy and only a minor proportion of patients present with significant coagulopathy.

The impact of a massive transfusion protocol on outcomes among patients with abdominal aortic injuries

BACKGROUND

Injuries of the abdominal aorta are uncommon and associated with a high mortality. The purpose of this study was to examine the impact of an institutional massive transfusion protocol (MTP) on outcomes in patients with injuries of the abdominal aorta.

METHODS

A 12.5-year retrospective analysis of a Level 1 trauma center database to identify patients with abdominal aortic injuries was conducted. Demographics, associated injuries and severity, operative procedures, resuscitation requirements, and outcomes were compared among patients before and after implementation of an MTP.

RESULTS

Of the 46 patients with abdominal aortic injuries, 29 (63%) were in the pre-MTP group and 17 (37%) were in the post-MTP group. The mean age of the entire cohort was 32 ± 17 years and the two most common mechanisms of injury were gunshot wounds (63%) followed by motor vehicle collisions (24%). Thirteen patients (28%) underwent an emergency department thoracotomy and 11 patients (24%) sustained concomitant inferior vena cava injuries. There was a significant reduction in the volume of pre- and intraoperative crystalloids administered between the pre- and post-MTP groups. Intraoperatively, the use of tranexamic acid was increased in the post-MTP group (P < 0.001). A statistically significant difference in achievement of a low packed red blood cells to fresh frozen plasma ratio was observed for the post- versus the pre-MTP group (88% vs. 30%, P = 0.015). Overall survival was improved among post- versus pre-MTP patients (47% vs. 14%, P = 0.03).

CONCLUSIONS

Abdominal aortic injuries continue to represent a challenge and remain associated with a high mortality. Modern improvements in damage control resuscitation techniques including implementation of an institutional MTP may improve outcomes in patients with these injuries.

Management of abdominal compartment syndrome and the open abdomen

OBJECTIVES

The management of the abdominal compartment syndrome (ACS) and the open abdomen (OA) are important to improve survival after major vascular surgery, in particular ruptured abdominal aortic aneurysm (RAAA). The aim is to summarize contemporary knowledge in this field.

METHODS

The consensus definitions of the World Society of the Abdominal Compartment Syndrome (WSACS) that were published in 2006 and the clinical practice guidelines published in 2007 were updated in 2013. Structured clinical questions were formulated (modified Delphi method), and the evidence base to answer those questions was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) guidelines.

RESULTS

Most of the previous definitions were kept untouched, or were slightly modified. Four new definitions were added, including a definition of OA and of lateralization of the abdominal wall, an important clinical problem to approach during prolonged OA treatment. A classification system of the OA was added. Seven recommendations were formulated, in summary: Trans-bladder intra-abdominal pressure (IAP) should be monitored in patients at risk. Protocolized monitoring and management are recommended, and decompression laparotomy if ACS. When OA, protocolized efforts to obtain an early abdominal fascial closure, and strategies utilizing negative pressure wound therapy should be used, versus not. In most cases the evidence was graded as weak or very weak. In six of the structured clinical questions, no recommendation could be made.

CONCLUSION

This review summarizes changes in definitions and management guidelines of relevance to vascular surgery, and data on the incidence of ACS after open and endovascular aortic surgery.

Risk factors affecting survival after surgical repair of ruptured abdominal aortic aneurysm

PURPOSE

The purpose of this study is to identify the risk factors affecting the high mortality rates associated with the treatment of ruptured abdominal aortic aneurysm (AAA).

METHODS

In this retrospective study, the subjects consisted of 105 patients who underwent repair of ruptured AAA at our institution from December 1984 to March 2012. We compared the patients of ruptured AAA in survival group with those in death group to evaluate the clinical factors in ruptured AAA mortality.

RESULTS

The operative and in-hospital mortality of ruptured AAA patients was 22.9% compared with 1.9% for that of non-ruptured AAA patients. The mean hemoglobin level was significantly lower in death group than in survival group. Intraoperative bleeding volume was significantly higher in death group than in survival group. Cox proportional hazard analysis showed that level 3 or 4 according to the Rutherford classification, preoperative hemoglobin level of less than 9.0 g/dl, intraoperative blood loss volume of more than 3000 ml, postoperative bowel ischemia and class 3 or 4 according to the Fitzgerald classification were significantly associated with high mortality.

CONCLUSION

These findings showed that every effort to maintain preoperative hemodynamic stability reduce volumes of blood loss in operation, and to minimize postoperative deterioration of organ functions would be essential to improve patient survival.

[The 2013 Seville Consensus Document on alternatives to allogenic blood transfusion. An update on the Seville Document]

Since allogeneic blood transfusion (ABT) is not harmless, multiple alternatives to ABT (AABT) have emerged, though there is great variability in their indications and appropriate use. This variability results from the interaction of a number of factors, including the specialty of the physician, knowledge and preferences, the degree of anemia, transfusion policy, and AABT availability. Since AABTs are not harmless and may not meet cost-effectiveness criteria, such variability is unacceptable. The Spanish Societies of Anesthesiology (SEDAR), Hematology and Hemotherapy (SEHH), Hospital Pharmacy (SEFH), Critical Care Medicine (SEMICYUC), Thrombosis and Hemostasis (SETH) and Blood Transfusion (SETS) have developed a Consensus Document for the proper use of AABTs. A panel of experts convened by these 6 Societies have conducted a systematic review of the medical literature and have developed the 2013 Seville Consensus Document on Alternatives to Allogeneic Blood Transfusion, which only considers those AABT aimed at decreasing the transfusion of packed red cells. AABTs are defined as any pharmacological or non-pharmacological measure aimed at decreasing the transfusion of red blood cell concentrates, while preserving patient safety. For each AABT, the main question formulated, positively or negatively, is: « Does this particular AABT reduce the transfusion rate or not?» All the recommendations on the use of AABTs were formulated according to the Grades of Recommendation Assessment, Development and Evaluation (GRADE) methodology.

[The 2013 Seville Consensus Document on alternatives to allogenic blood transfusion. An update on the Seville Document]

Since allogeneic blood transfusion (ABT) is not harmless, multiple alternatives to ABT (AABT) have emerged, though there is great variability in their indications and appropriate use. This variability results from the interaction of a number of factors, including the specialty of the physician, knowledge and preferences, the degree of anemia, transfusion policy, and AABT availability. Since AABTs are not harmless and may not meet cost-effectiveness criteria, such variability is unacceptable. The Spanish Societies of Anesthesiology (SEDAR), Hematology and Hemotherapy (SEHH), Hospital Pharmacy (SEFH), Critical Care Medicine (SEMICYUC), Thrombosis and Hemostasis (SETH) and Blood Transfusion (SETS) have developed a Consensus Document for the proper use of AABTs. A panel of experts convened by these 6 Societies have conducted a systematic review of the medical literature and have developed the 2013 Seville Consensus Document on Alternatives to Allogeneic Blood Transfusion, which only considers those AABT aimed at decreasing the transfusion of packed red cells. AABTs are defined as any pharmacological or non-pharmacological measure aimed at decreasing the transfusion of red blood cell concentrates, while preserving patient safety. For each AABT, the main question formulated, positively or negatively, is: "Does this particular AABT reduce the transfusion rate or not?" All the recommendations on the use of AABTs were formulated according to the Grades of Recommendation Assessment, Development and Evaluation (GRADE) methodology.

Frozen blood products: clinically effective and potentially ideal for remote Australia

The development of effective cryopreservation techniques for both red blood cells and platelets, which maintain ex vivo biological activity, in combination with frozen plasma, provides for a unique blood banking strategy. This technology greatly enhances the storage life of these products. The rationale and potential advantages of using cryopreservation techniques for the provision of blood products to remote and military environments have been effectively demonstrated in several conflicts over the last decade. Current haemostatic resuscitation doctrine for the exsanguinating patient supports the use of red blood cells, platelets and frozen plasma early in the resuscitation. We believe an integrated fresh-frozen blood bank inventory could facilitate provision of blood products, not only in the military setting but also in regional Australia, by overcoming many logistic and geographical challenges. The processes involved in production and point of care thawing are sufficiently well developed and achievable to make this technology a viable option. The potential limitations of cryopreservation and subsequent product thawing need to be considered if such a strategy is to be developed. A substantial body of international experience using cryopreserved products in remote settings has already been accrued. This experience provides a template for the possible creation of an Australian integrated fresh-frozen blood bank inventory that could conceivably enhance the care of patients in both regional Australia and in the military setting.

Hemorrhage and Transfusions in the Surgical Patient

Hemorrhage is the leading cause of intraoperative deaths. Many cardiovascular and hepatobiliary procedures result in massive hemorrhage and postpartum hemorrhage events in labor and delivery place the patient at a high risk for mortality. Gastrointestinal bleeding from diverticulosis, varices, and ulcer disease can result in significant blood loss requiring massive transfusion and resuscitation from hemorrhagic shock. Timely and effective transfusion of blood products is of critical in these scenarios. The frequency in which blood component products are transfused in surgical patients begs for a greater understanding of them. The aim of this chapter is to provide clinicians with a discussion of the current literature on the various blood component products, their indications, and unique hemostatic conditions in the surgical patient. While the majority of data concerning optimal management of acquired coagulopathy and hemorrhagic shock resuscitation is based on trauma patients, many of the principles can and should be applied to the surgical patient (or likely any patient) with profound hemorrhage.

Ruptured abdominal aortic aneurysm: the state of play

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) remains a challenging problem: 2,410 cases were treated in Germany in 2010. Ruptured abdominal aortic aneurysm should be suspected in patients over age 50 who complain of pain in the abdomen or back and in whom examination reveals a pulsatile abdominal mass. The incidence of hospitalization for rAAA is 12 per 100,000 persons over age 65 per year (statistics for Germany, 2010), and rAAA carries an overall mortality of 80%.

METHODS

The current state of knowledge of rAAA was surveyed in a selective review of pertinent literature retrieved by an electronic search in the PubMed, Web of Science, and Cochrane Library databases with the keywords "abdominal aortic aneurysm," "ruptured," "open repair," and "endovascular." Publications in English or German up to and including March 2012 were considered, among them the Clinical Practice Guidelines of the European Society for Vascular Surgery (1).

RESULTS AND CONCLUSIONS

Recent reports show that the treatment of rAAA is still fraught with high mortality and high perioperative morbidity. Improvement is needed. It would be advisable for the care of rAAA to be centralized in specialized vascular centers implementing defined treatment pathways. Systematic screening, too, would be beneficial. An increasing number of reports suggest that endovascular treatment with stent prostheses improves outcomes; more definitive evidence on this matter will come from prospective, randomized trials that are now in progress.

Management of the tense abdomen or difficult abdominal closure after operation for ruptured abdominal aortic aneurysms

Increased intra-abdominal pressure (IAP) and abdominal compartment syndrome (ACS) are important clinical problems after repair of ruptured abdominal aortic aneurysms and are reviewed here. IAP >20 mm Hg occurs in approximately 50% of patients treated with open abdominal aortic aneurysm repair after rupture, and approximately 20% develop organ failure or dysfunction, fulfilling the criteria for ACS. Patients selected for endovascular aneurysm repair are often more hemodynamically stable, perhaps related to not handling the viscera or more favorable anatomy, resulting in less bleeding and, consequently, decreased risk of developing ACS. Centers that treat most patients with endovascular aneurysm repair tend to have the same proportion of ACS as after open repair. There are no randomized data on these aspects. Early nonsurgical therapy can prevent development of ACS. Medical therapy includes neuromuscular blockade and the combination of positive end-expiratory pressure, albumin, and furosemide. This proactive strategy can reduce the number of decompressive laparotomies, an important detail because treatment of ACS with open abdomen is a morbid procedure. When treatment with an open abdomen is necessary, it is important to choose a temporary abdominal closure that maintains sterile conditions during often prolonged treatment. In addition, it should prevent lateralization of the bowel wall and adhesions between the intestines and the bowel wall. Enteroatmospheric fistulae must be prevented. Many alternative methods have been suggested, but we prefer the combination of vacuum-assisted wound closure with mesh-mediated traction, which will be described.

Predictors of postoperative mortality of ruptured abdominal aortic aneurysm: a retrospective clinical study

PURPOSE

Despite significant improvements in surgery, anesthesia, and postoperative critical care, the postoperative mortality rate of ruptured abdominal aortic aneurysm (RAAA) has remained at 40% to 50% for several decades. Therefore, we evaluated factors associated with the postoperative mortality of RAAA.

MATERIALS AND METHODS

From January 1999 to December 2008, a retrospective study was performed with 34 patients who underwent open repair of RAAA. The preoperative factors included age, sex, smoking, comorbidities, serum creatinine, hemoglobin, shock, pulse rate, and time from emergency room to operation room. The intraoperative factors included blood loss, transfusion, aortic clamping site and time, aneurysmal characteristics, rupture type, graft type, hourly urine output (HUO), and operative time. The postoperative factors included inotropic support, renal replacement therapy (RRT), reoperation, bowel ischemia, multiple organ failure (MOF), and intensive care unit stay. The 2-day and the 30-day mortality rates were analyzed separately.

RESULTS

The 2-day and the 30-day mortality rates were 14.7% and 41.2%, respectively. On univariate analysis, shock, transfusion, HUO, inotropic support and MOF for the 2-day mortality and serum creatinine, transfusion, aortic clamping site, HUO, inotropic support, RRT and MOF for the 30-day mortality were statistically significant. On multivariate analysis, shock, inotropic support and MOF for the 2-day mortality and aortic clamping site, RRT and MOF for the 30-day mortality were statistically significant.

CONCLUSION

To decrease the postoperative mortality rate of RAAA, prevention of massive hemorrhage and acute renal failure with infrarenal aortic clamping, as well as prompt operative control of bleeding and maintenance of systemic perfusion are important.

Management of the clotting system: a European perspective

PURPOSE OF REVIEW

Coagulation management remains a challenge for anesthesiologists involved in cardiovascular surgery as the population undergoing surgery becomes older and presents with more comorbidities. These patients are frequently treated with one or more agents that directly affect coagulation. This review will discuss what is known and the treatments available to manage coagulation in the perioperative setting of cardiac surgery.

RECENT FINDINGS

New antithrombotics will be discussed as well as their proposed substitution in the preoperative period. The review will also describe the different products available in Europe for the treatment of bleeding and coagulopathy. Finally, the use of new monitoring devices will be discussed.

SUMMARY

The introduction of new drugs with different mechanisms of action adds to the complexity of coagulation management during cardiovascular surgery. Monitoring needs to be developed and improved, especially for evaluating platelet function.

Intraoperative blood product resuscitation and mortality in ruptured abdominal aortic aneurysm

OBJECTIVES

The resuscitation of patients with ruptured abdominal aortic aneurysms (RAAAs) has not been well studied, and the potential benefit of autotransfusion (AT) is unknown. The increased use of fresh-frozen plasma (FFP) has been associated with decreased mortality rates in trauma patients and may also improve RAAA survival. We explored the influence of intraoperative AT and FFP resuscitation on mortality rates in massively transfused RAAA patients.

METHODS

A single-center review of RAAA patient records from April 1989 to October 2009 was undertaken. Clinical data and outcomes were studied. Operative and anesthesia records were queried for intraoperative transfusion totals. Massive transfusion was defined as ≥10 units of red blood cells (RBCs) inclusive of AT units.

RESULTS

We identified 151 RAAA patients, of which 89 (60%) received a massive transfusion and comprised the study population. These 89 patients had an in-hospital mortality rate of 44%. Univariate predictors of mortality included increased age, preoperative hypotension, operative blood loss, and crystalloid, RBCs, and FFP volume. AT was used in 85 patients, with an increased ratio of AT:RBC units associated with survival. Mortality was 34% with AT:packed RBCs (PRBC) ≥1 (high AT) and 55% with AT:PRBC of <1 (low AT; P = .04). On multivariate analysis, age > 74 years (P = .03), lowest preoperative systolic blood pressure (SBP) <90 mm Hg (P = .06), blood loss >6 liters (P = .06), and low AT (P = .02) independently predicted mortality. The mean RBC:FFP ratio was similar in those that died (2.7) and in those that lived (2.9; P = .66). RBC:FFP ≤2 (high FFP) was present in 38 (43%) patients, with mortality of 49%. RBC:FFP >2 (low FFP) had 40% mortality (P = .39). RBC:FFP ratios decreased over time from 3.6 (years 1989 to 1999) to 2.2 (years 2000 to 2009; P < .001), but more liberal use of FFP was not associated with decreased mortality (47% vs 41%; P = .56). AT:PRBC ratios were stable over time (range, 1.4-1.2; P = .18).

CONCLUSIONS

Greater use of AT but not of FFP was associated with survival in massively transfused RAAA patients. No mortality benefit was seen with increased FFP, but few patients had high FFP transfusion ratios. Further study to identify RAAA patients at risk for massive transfusion should be undertaken and a potentially greater role for AT in RAAA resuscitation investigated.

Clinical review: Canadian National Advisory Committee on Blood and Blood Products--Massive transfusion consensus conference 2011: report of the panel

In June 2011 the Canadian National Advisory Committee on Blood and Blood Products sponsored an international consensus conference on transfusion and trauma. A panel of 10 experts and two external advisors reviewed the current medical literature and information presented at the conference by invited international speakers and attendees. The Consensus Panel addressed six specific questions on the topic of blood transfusion in trauma. The questions focused on: ratio-based blood resuscitation in trauma patients; the impact of survivorship bias in current research conclusions; the value of nonplasma coagulation products; the role of protocols for delivery of urgent transfusion; the merits of traditional laboratory monitoring compared with measures of clot viscoelasticity; and opportunities for future research. Key findings include a lack of evidence to support the use of 1:1:1 blood component ratios as the standard of care, the importance of early use of tranexamic acid, the expected value of an organized response plan, and the recommendation for an integrated approach that includes antifibrinolytics, rapid release of red blood cells, and a foundation ratio of blood components adjusted by results from either traditional coagulation tests or clot viscoelasticity or both. The present report is intended to provide guidance to practitioners, hospitals, and policy-makers.

From whole blood to component therapy: the economic, supply/demand need for implementation of component therapy in sub-Saharan Africa

Blood may be transfused as whole blood or as one of its components. Because patients seldom require all of the components of whole blood, it makes sense to transfuse only that portion needed by the patient for a specific condition or disease. This treatment, known as "blood component therapy", allows several patients to benefit from one unit of donated whole blood. Blood components include red blood cells, plasma, platelets, and cryoprecipitate. A considerable literature has accumulated over the past decade indicating that leukocytes present in allogeneic cellular blood components, intended for transfusion, are associated with adverse effects to the recipient. These include the development of febrile transfusion reactions, graft-versus-host disease, alloimmunization to leukocyte antigens, and the immunomodulatory effects that might influence the prognosis of patients with a malignancy. Moreover, it has become evident that such leukocytes may be the vector of infectious agents such as cytomegalovirus (CMV), Human T-Lymphotrophic Virus 1/11 (HTLV-I/II), and Epstein Barr (EBV) as well as other viruses. Effective stewardship of blood ensuring that several patients potentially benefit from components derived from one unit of donated whole blood is important for economic, supply/demand reasons and to protect the national inventory at times of national blood shortage. Blood safety in developing countries can be improved by more appropriate use of blood components rather than whole blood transfusion and the provision of alternatives such as oral and intravenous iron, erythropoietin, saline and colloids. This will facilitate the optimal use of the limited blood supply. Political will and open-mindedness to innovative ways to improve supply, appropriateness, optimal use and safety of blood from all types of donors are essential to promote more evidence-based approaches to blood transfusion practice in sub-Saharan Africa.

Clinical effectiveness of fresh frozen plasma compared with fibrinogen concentrate: a systematic review

Introduction

Haemostatic therapy in surgical and/or massive trauma patients typically involves transfusion of fresh frozen plasma (FFP). Purified human fibrinogen concentrate may offer an alternative to FFP in some instances. In this systematic review, we investigated the current evidence for the use of FFP and fibrinogen concentrate in the perioperative or massive trauma setting.

Methods

Studies reporting the outcome (blood loss, transfusion requirement, length of stay, survival and plasma fibrinogen level) of FFP or fibrinogen concentrate administration to patients in a perioperative or massive trauma setting were identified in electronic databases (1995 to 2010). Studies were included regardless of type, patient age, sample size or duration of patient follow-up. Studies of patients with congenital clotting factor deficiencies or other haematological disorders were excluded. Studies were assessed for eligibility, and data were extracted and tabulated.

Results

Ninety-one eligible studies (70 FFP and 21 fibrinogen concentrate) reported outcomes of interest. Few were high-quality prospective studies. Evidence for the efficacy of FFP was inconsistent across all assessed outcomes. Overall, FFP showed a positive effect for 28% of outcomes and a negative effect for 22% of outcomes. There was limited evidence that FFP reduced mortality: 50% of outcomes associated FFP with reduced mortality (typically trauma and/or massive bleeding), and 20% were associated with increased mortality (typically surgical and/or nonmassive bleeding). Five studies reported the outcome of fibrinogen concentrate versus a comparator. The evidence was consistently positive (70% of all outcomes), with no negative effects reported (0% of all outcomes). Fibrinogen concentrate was compared directly with FFP in three high-quality studies and was found to be superior for > 50% of outcomes in terms of reducing blood loss, allogeneic transfusion requirements, length of intensive care unit and hospital stay and increasing plasma fibrinogen levels. We found no fibrinogen concentrate comparator studies in patients with haemorrhage due to massive trauma, although efficacy across all assessed outcomes was reported in a number of noncomparator trauma studies.

Conclusions

The weight of evidence does not appear to support the clinical effectiveness of FFP for surgical and/or massive trauma patients and suggests it can be detrimental. Perioperatively, fibrinogen concentrate was generally associated with improved outcome measures, although more high-quality, prospective studies are required before any definitive conclusions can be drawn.