Perioperative Red Blood Cell Transfusion and Outcome in Stable Patients after Elective Major Vascular Surgery

Impact of Preoperative Anemia on Hospitalization, Death, and Overall Survival in Patients With Peripheral Artery Disease Undergoing Endovascular Therapy: A Retrospective Cohort Study in the United States and Canada

PURPOSE

Preoperative anemia is associated with adverse outcomes after cardiac and noncardiac surgeries, but outcomes after an endovascular peripheral vascular intervention (PVI) are not well established. We aimed to assess the association of preoperative anemia with 30 day death, hospital length of stay (LOS), and overall (long term) survival in patients undergoing an endovascular PVI for peripheral artery disease.

MATERIALS AND METHODS

In this retrospective, cohort study in the United States and Canada, we queried the national Vascular Quality Initiative database for all endovascular PVIs performed between 2010 and 2019, and outcomes were correlated with patients' hemoglobin (Hb) levels. Anemia was classified as mild (Hb=10-13 g/dL for men and 10-12 g/dL for women), moderate (Hb=8-9.9 g/dL), and severe (Hb<8 g/dL).

RESULTS

A total of 79 707 adult patients who met study criteria underwent endovascular PVI. The mean age was 68 years, and 59% of patients were male. Anemia was documented in 38 543 patients (48%) and was mild in 27 435 (71%), moderate in 9783 (25%), and severe in 1325 (4%). The median follow-up duration was 4 years (range, 1.25-5.78 years). On univariate analysis, 30 day mortality, total LOS, and overall survival were significantly associated with the level of preoperative anemia. These associations persisted in the multivariate models. Kaplan-Meier survival analysis demonstrated an association of death with degree of anemia (p<0.001).

CONCLUSION

The presence and degree of preoperative anemia were independently associated with increased 30 day mortality and LOS and decreased overall survival for patients with peripheral artery disease who had undergone endovascular PVI.

CLINICAL IMPACT

The findings from this study have many implications for how to approach vascular surgery in patients with variable hemoglobin levels. Our findings will strengthen our ability to conduct accurate preoperative risk stratification for patients undergoing peripheral vascular interventions. This may also mitigate healthcare expenditures if findings are applied in a way that can lower patient length of postoperative stay while also maintaining quality of care and patient safety. Our results will also serve as guidance for clinical trials, and future prospective trials should evaluate the effect of preoperative optimization of hemoglobin as a potentially modifiable risk factor for outcomes.

Direct Reinfusion of Unwashed Shed Autologous Blood During Thoracoabdominal Aortic Aneurysm Repair: A Retrospective Analysis

BACKGROUND

This study's purpose was to assess whether larger volumes of reinfused unwashed shed autologous blood (SAB) were associated with adverse events within 30 days for patients undergoing open thoracoabdominal aortic aneurysm (TAAA) repair. During TAAA repair, our institution uses a system wherein SAB is filtered, but not washed or centrifuged, and then returned to the patient via a rapid-infusion device. By reinfusing SAB, the system preserves the patient's autologous whole blood and may reduce the number of allogenic transfusions required during TAAA repair, but the end-organ effects of reinfusing unwashed SAB have not been extensively evaluated.

METHODS

Using a prospectively maintained database, we retrospectively analyzed data from 972 consecutive patients who underwent open TAAA repair at our institution from 2007 to 2021 and who received SAB. Multivariable logistic regressions were performed to assess whether SAB reinfusion volume was associated with a composite outcome of adverse events, as well as operative mortality, a composite of cardiac complications, a composite of pulmonary complications, or persistent paraplegia, stroke, or postoperative renal failure.

RESULTS

Among the cohort of 972 patients, the median volume of reinfused SAB was 4159 mL (quartile1-quartile3 [Q1-Q3]: 2524-6790 mL). Greater reinfusion volumes of unwashed SAB were not associated with greater odds of composite adverse events (odds ratio [OR], 1.02 per 1000 mL increase, 97.5% confidence interval [CI], 0.94-1.09, P = .624), nor with any individual outcome-operative mortality (OR, 1.02 per 1000 mL increase, 97.5% CI, 0.93-1.12, P = .617), a composite of cardiac complications (OR, 0.98 per 1000 mL increase, 97.5% CI, 0.93-1.04, P = .447), a composite of pulmonary complications (OR, 1.00 per 1000 mL increase, 97.5% CI, 0.94-1.06, P = .963), renal failure necessitating hemodialysis (OR, 1.01 per 1000 mL increase, 97.5% CI, 0.92-1.11, P = .821), persistent paraplegia (OR, 0.97 per 1000 mL increase, 97.5% CI, 0.84-1.13, P = .676), persistent stroke (OR, 0.85 per 1000 mL increase, 97.5% CI, 0.70-1.04, P = .070), or reoperation to control bleeding (OR, 0.99, 97.5% CI, 0.87-1.13, P = .900)-when adjusted for confounders.

CONCLUSIONS

For patients undergoing open TAAA repair, larger reinfusion volumes of unwashed SAB were not associated with greater odds of major early postoperative complications.

Clinical Effects of Tourniquet Use for Nontraumatic Major Lower Limb Amputation: A Two-Center Retrospective Cohort Study

BACKGROUND

To investigate the effect of tourniquet use on outcomes after major lower limb amputation (MLLA) due to peripheral arterial disease or complications from diabetes mellitus.

METHODS

In this 2-center retrospective observational study, vascular patients who underwent MLLA between January 1, 2016 and December 31, 2020 at 2 UK hospitals were identified using operating theater databases. Hospital databases were used to access medical records, operation notes, and laboratory reports. The use of a tourniquet in each MLLA was noted. The primary outcome was postoperative hemoglobin (Hb) drop (g/L). Secondary outcomes were units of allogeneic blood transfused perioperatively, 90-day revision rates, 90-day wound breakdown rates, surgical site infection (SSI) rates (at 30 days), and 90-day mortality. A follow-up index (a measure of follow-up completeness) was calculated for all 30-day and 90-day outcomes.

RESULTS

Four hundred seventy two patients underwent MLLA, of which 124 had a tourniquet applied. The median postoperative Hb drop was significantly lower in the tourniquet group compared to the nontourniquet group (13 [interquartile range 5-22] g/L vs. 20 [interquartile range 11-28] g/L; P ≤ 0.001). Thirty three point one percent (41) of tourniquet patients received a blood transfusion perioperatively, compared to 35.6% (124) of nontourniquet patients (P = 0.82). Sixteen percent (76) of patients required surgical revision within 90 days, with no significant difference between the tourniquet and nontourniquet group (20.2% tourniquet vs. 14.7% no tourniquet; P = 0.15). SSI rates (12.0% tourniquet vs. 10.6% no tourniquet, P = 0.66) and 90-day mortality (6.5% tourniquet vs. 10.1% no tourniquet; P = 0.23) were similar. Multivariable regression demonstrated that tourniquet use was independently associated with a reduced hemoglobin drop (β = -4.671, 95% confidence interval -7.51 to -1.83, P ≤ 0.001) but was not associated with wound breakdown, revision surgery, or SSI. Hypertension, SSI, and below-knee amputation using the skew flap technique were all significant predictors of revision surgery. All follow-up indices were ≥ 0.97.

CONCLUSIONS

Tourniquet use in MLLA was associated with a significantly lower fall in postoperative Hb without evidence of harm in terms of SSI, wound breakdown/revision rates, or mortality.

Robot Navigation System Assisted PFNA Fixation of Femoral Intertrochanteric Fractures in the Elderly: A Retrospective Clinical Study

Objective

The incidence of hip fracture in the elderly is increasing. Robot navigation technology has the advantages of minimally invasive and accurate. To explore the difference between the clinical effects of proximal femoral anti-rotation intramedullary nail (PFNA) assisted by robot navigation in the treatment of femoral intertrochanteric fracture and traditional PFNA in the treatment of femoral intertrochanteric fracture in the elderly; analyze the advantages and feasibility of PFNA assisted by robot navigation in the treatment of femoral intertrochanteric fracture in the elderly.

Patients and Methods

From February 2021 to October 2022, the elderly (>65 years old) with femoral intertrochanteric fracture underwent surgery in our center. Divided the patients included in the study into 2 groups based on the surgical method. The surgical method of robot group was PFNA fixation assisted by robot navigation, while the surgical method of traditional group was classic PFNA fixation, Baseline data (general condition, Evans classification, time from injury to operation, preoperative hemoglobin) and observation indicators (intraoperative bleeding, operation time, the length of incision for mail nail insertion, postoperative hemoglobin drop, blood transfusion rate and the Harris score of hip joint 1 year after operation) of the two groups were collected to compare whether there were differences between the two groups.

Results

There was no statistical difference in baseline data between the two groups (P>0.05). The intraoperative bleeding in the robot group was 68.17±10.66 mL, the intraoperative bleeding in the traditional group was 174±8.11mL (P<0.001). The operation time in the robot group was 68.81 ± 6.89 min, in the traditional group, the operation time was 76.94 ± 8.18 min (P<0.001). The length of incision for mail nail insertion in the robot group was 3.53 ± 0.63 cm, the length of the incision for mail nail insertion in the traditional group was 4.23 ± 0.71 cm (P<0.001). 5 patients (13.9%) in the robot group received blood transfusion treatment, and 13 patients (36.1%) in the traditional group received blood transfusion treatment (P=0.029). The hemoglobin in the robot group decreased by 14.81 ± 3.27 g/l after operation compared with that before operation, while that in the traditional group decreased by 16.69 ± 3.32 g/l (P=0.018). The Harris score of the hip joint of the affected limb in the robot group was excellent in 25 cases, good in 8 cases and poor in 3 cases one year after the operation; In the traditional group, Harris scores were excellent in 18 cases, good in 11 cases and poor in 7 cases (P=0.021).

Conclusion

PFNA fixation of femoral intertrochanteric fracture with robot navigation assistance has the advantages of minimally invasive and accurate, shorter operation time, less bleeding and lower blood transfusion rate than traditional surgical methods, and has certain advantages in reducing postoperative complications of elderly patients.

Critical Care of the Vascular Surgery Patient

Patients that require major vascular surgery suffer from widespread atherosclerosis and have multiple comorbidities that place them at increased risk for postoperative complications and require admission to the intensive care unit (ICU). Postoperative critical care of these patients is focused on hemodynamic optimization, and early identification and management of complications to improve outcomes.

Peri-procedural complications following endovascular revascularization for critical limb ischemia

OBJECTIVE

Revascularization procedures are considered the cornerstone of therapy in patients with critical limb ischemia (CLI) and multiple procedures are often required to attain limb salvage. The aim of the present study is to determine the prevalence of peri-procedural complications after endovascular procedure, and to determine the clinical and biological characteristics of patients associated to the risk of peri-procedural complications.

METHODS

From November 2013 to May 2021, 324 consecutive patients were retrospectively included, of whom 99 underwent more than one revascularization procedure for contralateral CLI or clinical recurrence of CLI. A total of 532 revascularizations were performed. Clinical and biological parameters were recorded at baseline before endovascular revascularization. The occurrence of a peri-procedural complication (local complications, fatal and non-fatal major bleeding or cardiovascular events) was recorded up to 30days after revascularization. Univariate and multivariate analyses were performed to study the parameters associated with per-procedural complications. A P<0.05 was considered as statistically significant.

RESULTS

A total of 324 consecutive patients were included, 177 men and 147 women with CLI, with a mean age of 77.6±11.9years. Most of these patients had cardiovascular comorbidities (41% with a history of coronary heart disease, 78% treated hypertensive patients, 49% diabetic patients). Peri-procedural mortality occurred in 13 patients (4%) and 9 patients (2.8%) experienced major amputation at one-month following revascularization. Among the 532 revascularization procedures, 99 major bleeding events (22.8% of the cohort population) and 31 cardiovascular events (8.6% of the cohort population), were recorded in the peri-procedural period. Cardiovascular events were associated with peri-procedural mortality. Complications at the puncture site occurred during 38 of the 532 procedures (10.2% of the cohort population). Compared with patients undergoing a single revascularization procedure, patients with multiple procedures presented a higher risk of major bleeding events (48.5% vs. 11.6%, P<0.0001) and access site complications (20.2% vs. 5.78%, P<0.0001). In multivariate analysis, pulse pressure <60mmHg and hemoglobin level <10g/dl were correlated with the occurrence of major bleeding events; left ventricular ejection fraction<60% and the absence of statin treatment were correlated with the occurrence of cardiovascular complications; a high chronological rank of revascularization was correlated with the occurrence of local complication. Finally, age and gender were not associated with the occurrence of peri-procedural complication.

CONCLUSION

The present results highlight that multiple revascularization procedures for limb salvage are required in almost one third of the population with critical limb ischemia and were associated with the risk of major bleeding events and access site complications. The most frequent complications of peripheral vascular interventions were major bleeding events. Adverse cardiovascular events were related with peri-procedural mortality. Anemia, blood pressure, left ventricular ejection fraction and statin treatment are important parameters to consider for peri-procedural outcomes, independently of age, gender and the chronological rank of revascularization procedure.

Impact of restrictive red blood cell transfusion strategy on thrombosis-related events: A meta-analysis and systematic review

BACKGROUND AND OBJECTIVES

There is an ongoing controversy regarding the risks of restrictive and liberal red blood cell (RBC) transfusion strategies. This meta-analysis assessed whether transfusion at a lower threshold was superior to transfusion at a higher threshold, with regard to thrombosis-related events, that is, whether these outcomes can benefit from a restrictive transfusion strategy is debated.

MATERIALS AND METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials and Scopus from inception up to 31 July 2021. We included randomized controlled trials (RCTs) in any clinical setting that evaluated the effects of restrictive versus liberal RBC transfusion in adults. We used random-effects models to calculate the risk ratios (RRs) and 95% confidence intervals (CIs) based on pooled data.

RESULTS

Thirty RCTs involving 17,334 participants were included. The pooled RR for thromboembolic events was 0.65 (95% CI 0.44-0.94; p = 0.020; I²  = 0.0%, very low-quality evidence), favouring the restrictive strategy. There were no significant differences in cerebrovascular accidents (RR = 0.83; 95% CI 0.64-1.09; p = 0.180; I²  = 0.0%, very low-quality evidence) or myocardial infarction (RR = 1.05; 95% CI 0.87-1.26; p = 0.620; I²  = 0.0%, low-quality evidence). Subgroup analyses showed that a restrictive (relative to liberal) strategy reduced (1) thromboembolic events in RCTs conducted in North America and (2) myocardial infarctions in the subgroup of RCTs where the restrictive transfusion threshold was 7 g/dl but not in the 8 g/dl subgroup (with a liberal transfusion threshold of 10 g/dl in both subgroups).

CONCLUSIONS

A restrictive (relative to liberal) transfusion strategy may be effective in reducing venous thrombosis but not arterial thrombosis.

Expanded use of tranexamic acid is safe and decreases transfusion rates in patients with geriatric hip fractures

Objectives:

To determine the effect of a standardized tranexamic acid (TXA) protocol on red blood cell transfusions and adverse events in fragility hip fracture patients.

Design:

Retrospective cohort study.

Setting:

Academic Tertiary Care Center.

Patients/Participants:

Series of 209 patients with fragility hip fractures treated operatively from April 1, 2019 to September 30, 2019.

Intervention:

Eligible patients received 4 intravenous doses of TXA. Some patients missed doses and only received between 1 and 3 doses of TXA: Ineligible patients received no TXA. Patients with medical conditions precluding the use of TXA were deemed ineligible: allergy to TXA; creatinine clearance <30 mL/min; active malignancy; vascular event in the past year; anticoagulant use; fracture > 48 hours prior to presentation.

Main Outcome Measures:

Red blood cell transfusion; major adverse vascular events; minor drug related adverse events.

Results:

Patients who received all 4 doses of TXA (n = 70) had a significantly lower transfusion rate compared to those who did not receive any TXA (7.1% vs 28.1%, P = .003). There were no significant differences in the number of major or minor adverse events between the 2 groups.

Conclusions:

The use of a standardized TXA protocol of 4 doses significantly decreases transfusion rates in eligible patients undergoing operative intervention for fragility hip fracture without an increase in major or minor adverse events. These findings are even more pronounced in patients with decreased preoperative hemoglobin.

Level of Evidence: Prognostic Level III

Physiological and Clinical Impact of Repeated Inhaled Oxygen Variation on Erythropoietin Levels in Patients After Surgery

The “Normobaric Oxygen Paradox” (NOP) is a physiologic mechanism that induces an increase of endogenous erythropoietin (EPO) production by creating a state of relative hypoxia in subjects previously exposed to hyperoxia, followed by a rapid return to normoxia. Oxygen exposure duration and inspired oxygen fraction required to observe a significant increase in EPO or hemoglobin are not clearly defined. Consequently, we here study the effect of one model of relative hypoxia on EPO, reticulocytes and hemoglobin stimulation in patients after surgery. Patients were prospectively randomized in two groups. The O₂ group (n = 10) received 100% oxygen for 1 h per day for eight consecutive days, via a non-rebreathing mask. The control group (n = 12) received no oxygen variation. Serum EPO, hemoglobin and reticulocyte count were measured on admission and postoperatively on days seven and nine. Percentage EPO at day nine with respect to the baseline value was significantly elevated within the groups [O₂ group: 323.7 (SD ± 139.0); control group: 365.6 (SD± 162.0)] but not between them. No significant difference was found between the groups in terms of reticulocytes count and hemoglobin. Our NOP model showed no difference on EPO increase between the two groups. However, both groups expressed separately significant EPO elevation.

Impact of Perioperative Blood Transfusion in Anemic Patients Undergoing Infra Inguinal Bypass

OBJECTIVE

Patients who present with lower extremity ischemia are frequently anemic and the optimal transfusion threshold for this cohort remains controversial. We sought to evaluate the impact of blood transfusion on postoperative major adverse cardiac events (MACE), including myocardial infarction, dysrhythmia, stroke, congestive heart failure, and 30-day mortality for these patients.

METHODS

All consecutive patients who underwent infra-inguinal bypass at our institution from 2011 to 2020 were included. Perioperative red blood cell transfusion was the primary exposure, and the primary outcome was MACE. Univariate and multivariable analyses were performed to assess the impact of patient and procedural variables, including red blood cell transfusion, stratified by hemoglobin (Hgb) nadir: <7, 7-8, and >8 g/dL.

RESULTS

Of the 287 patients reviewed for analysis, 146 (50.9%) had a perioperative transfusion (mean: 1.6 ± 3 units). Patients who received a transfusion had a mean nadir Hgb of 8.3 ± 1.0 g/dL, compared to 10.1 ± 1.7 g/dL without a transfusion. The overall incidence of MACE was 15.7% (45 of 287 patients). Univariate analysis demonstrated that MACE was associated with blood transfusion (P = 0.009), lower Hgb nadir (P = 0.02), and higher blood loss (P = 0.003). On multivariate analysis, transfusion was independently associated with MACE for patients with a Hgb nadir >8 g/dL (OR: 3.09; P = 0.006), but not for patients with Hgb nadir 7-8 g/dL (OR: 0.818; P = 0.77). Additionally, patients with MACE had significantly longer length of hospital stay than for patients without (13 vs. 7.7 days, P = 0.001).

CONCLUSIONS

For patients undergoing infra-inguinal bypass, receiving a red blood cell transfusion with a Hgb nadir >8 g/dL was associated with a 3-fold increase in MACE, with nearly twice the length of stay. For patients with a Hgb 7-8 g/dL, transfusion did not increase or reduce the incidence of MACE. These findings suggest no benefit of blood transfusion for patients with Hgb nadir >7 g/dL and harm for Hgb >8 g/dL, however causation cannot be proven due to the retrospective nature of the study and randomized studies are needed to confirm or refute these findings.

Peripheral arterial disease and anaemia. A review

Iron deficiency anaemia is highly prevalent worldwide. In the surgical patient, anaemia of any cause implies higher morbidity and mortality in the post-operative period. This is especially important in patients with peripheral artery disease, as they have very high rates of anaemia due to iron deficiency or other causes. In intermittent claudication, anaemia is a predictor of death in the medium term. Patients with critical ischaemia have higher prevalence of anaemia and it is an indicator of amputation and death in the medium term. Specific protocols need to be developed for these patients since the natural history of their disease does not allow for the correction of anaemia before surgery.

Efficacy and cost-effectiveness of cell saver usage in the repair of thoracic aortic aneurysms and dissections

INTRODUCTION

A substantial amount of blood loss occurs during the open repair of aortic aneurysms or dissections. The aim of the present study is to determine the efficacy and cost-effectiveness of cell saver devices in blood conservation during the open repair of thoracic aortic pathologies.

METHODS

The present study prospectively collected the data pertaining to 25 patients who underwent surgical management of thoracic aortic aneurysms or dissections using a cell saver (Group 1, n = 25). The volume and cost of transfusion and postoperative outcomes were compared with the second group of patients who underwent surgery without the use of cell savers in the previous year (Group 2, n = 25); the data pertaining to the same were retrospectively collected from the hospital records. The patient characteristics and categorical variables were compared using the x² test and Fisher's exact test. Transfusion volume and costs were compared using the independent samples t-test and Mann-Whitney U test.

RESULTS

The patients in both the groups displayed similar characteristics and risk factors. The total volume of allogenic red blood cell (p < 0.001) and total blood product (p = 0.01) transfusions were significantly lower in Group 1. The cost of red blood cell (p < 0.001) and total transfusions (p = 0.03) were lower in Group 1. The two groups displayed similar in-hospital morbidity and mortality rates.

CONCLUSIONS

There was a significant association between the use of cell savers and the decreased need for red blood cell and total blood product transfusions. Considering the cost of the cell saver set, transfusion costs in the two groups were comparable.

Anaemia: A risk factor for death and adverse outcomes following surgery for acute lower limb ischaemia

INTRODUCTION

Acute limb ischaemia (ALI) forms a significant part of the vascular surgery workload and carries with it high rates of morbidity and mortality. Anaemia is also common amongst vascular surgical patients and has been linked with poor outcomes in some subgroups. We aimed to assess the frequency of anaemia in patients with ALI and its impact on survival and complications following revascularisation to help direct future efforts to optimise outcomes in this patient group.

METHODS

A retrospective analysis of prospectively collected departmental data on patients undergoing surgical intervention for ALI between 2014 and 2018 was performed. Anaemia was defined as a pre-operative haemoglobin (Hb) of <120 g/L for women and <130 g/L for men. The primary outcome was overall survival, assessed with the Kaplan-Meier estimator, with application of Cox proportional hazard modelling to adjust for confounding covariates.

RESULTS

There were 158 patients who underwent treatment for ALI: 89 (56.3%) of these were non-anaemic with a mean Hb of 146 (SD = 18.4), and 69 (43.7%) were anaemic with a mean Hb of 106 (SD = 13.4). Anaemic patients had a significantly higher risk of death than their non-anaemic counterparts on univariate analysis (HR = 2.11, 95% CIs, 1.28-3.5, p = 0.0036). There was ongoing divergence in survival up to around 6 months between anaemic and non-anaemic groups. Under the Cox model, anaemia was similarly significant as a predictor of death (HR = 2.15, 95% CIs, 1.17-3.95, p = 0.013), accounting for recorded comorbidities, medication use and blood transfusion.

CONCLUSIONS

Anaemia is a significant and independent risk factor for death following revascularisation for ALI and can be potentially be modified. Vascular surgical centres should ensure they have robust pathways in place to identify and consider treating anaemia. There is scope for further work to assess how to best optimise a patient's levels of circulating haemoglobin.

The effects of preoperative moderate to severe anaemia on length of hospital stay: A propensity score-matched analysis in non-cardiac surgery patients

BACKGROUND

Anaemia is frequently recorded during preoperative screening and has been suggested to affect outcomes after surgery negatively.

OBJECTIVES

The objectives were to assess the frequency of moderate to severe anaemia and its association with length of hospital stay.

DESIGN

Post hoc analysis of the international observational prospective 'Local ASsessment of VEntilatory management during General Anaesthesia for Surgery' (LAS VEGAS) study.

PATIENTS AND SETTING

The current analysis included adult patients requiring general anaesthesia for non-cardiac surgery. Preoperative anaemia was defined as a haemoglobin concentration of 11 g dl-1 or lower, thus including moderate and severe anaemia according to World Health Organisation criteria.

MAIN OUTCOME MEASURES

The primary outcome was length of hospital stay. Secondary outcomes included hospital mortality, intra-operative adverse events and postoperative pulmonary complications (PPCs).

RESULTS

Haemoglobin concentrations were available for 8264 of 9864 patients. Preoperative moderate to severe anaemia was present in 7.7% of patients. Multivariable analysis showed that preoperative moderate to severe anaemia was associated with an increased length of hospital stay with a mean difference of 1.3 ((95% CI 0.8 to 1.8) days; P < .001). In the propensity-matched analysis, this association remained present, median 4.0 [IQR 1.0 to 5.0] vs. 2.0 [IQR 0.0 to 5.0] days, P = .001. Multivariable analysis showed an increased in-hospital mortality (OR 2.9 (95% CI 1.1 to 7.5); P  = .029), and higher incidences of intra-operative hypotension (36.3 vs. 25.3%; P < .001) and PPCs (17.1 vs. 10.5%; P = .001) in moderately to severely anaemic patients. However, this was not confirmed in the propensity score-matched analysis.

CONCLUSIONS

In this international cohort of non-cardiac surgical patients, preoperative moderate to severe anaemia was associated with a longer duration of hospital stay but not increased intra-operative complications, PPCs or in-hospital mortality.

TRIAL REGISTRATION

The LAS VEGAS study was registered at Clinicaltrials.gov, NCT01601223.

Prognostic Value of Preoperative Hemoglobin Levels for Long-Term Outcomes of Acute Type B Aortic Dissection Post-thoracic Endovascular Aortic Repair

Background and Aims: There is scant information available about the prognostic value of preoperative hemoglobin (Hb) levels on the long-term outcomes of acute type B aortic dissection (ABAD) following thoracic endovascular aortic repair (TEVAR).

Methods: A retrospective analysis of consecutive patients from 2010 to 2018 regarding the relationship between Hb level and long-term outcomes was conducted. The primary endpoint was all-cause mortality. Major adverse cardiovascular events (MACEs) included all-cause death, recurrent ruptures, and secondary procedures.

Results: In total, 391 subjects treated by TEVAR were enrolled, with a mean age of 57.1 ± 12.0 years; 79.5% of them were male. Cox multivariate analysis showed that the preoperative Hb level was independently associated with all-cause death [adjusted hazard ratio (HR) 0.797 (per 1 g/dl), 95% confidence interval (CI) 0.693–0.918, p = 0.002] and MACEs (adjusted HR 0.795, 95% CI 0.672–0.871, p = 0.000). The area under the receiver operating characteristic curve of Hb for all-cause death and MACEs were 0.617 (95% CI 0.548–0.687, p = 0.008) and 0.617 (95% CI 0.551–0.684, p = 0.005), respectively. In the linear trend test, Hb concentration was significantly related to all-cause mortality (p for trend = 0.001) and MACEs (p for trend = 0.000). Moreover, in Kaplan–Meier analysis, lower Hb levels (< 12 g/dl) were significantly different from higher Hb (≥12 g/dl) levels for both all-cause death (log-rank p = 0.001) and MACEs (log-rank p = 0.001). Similar results were found when assessing the prognostic value of red blood cell count and anemia.

Conclusions: Preoperative Hb may serve as a prognostic marker for long-range adverse outcomes for ABAD patients post-TEVAR.

Effect of Blood Loss and Transfusion Requirements on Clinical Outcomes of Fenestrated-Branched Endovascular Aortic Repair

OBJECTIVE

The aim of this study was to evaluate the effect of blood loss and transfusion requirements on clinical outcomes of patients treated by fenestrated-branched endovascular aortic repair (F-BEVAR) for pararenal (PRA) and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

We reviewed the clinical data of 370 consecutive patients (277 male, mean age 74 ± 10 years) treated by F-BEVAR between 2007 and 2017. Outcomes were estimated blood loss (EBL), use of intraoperative blood salvage (IOBS), transfusion of packed red blood cells (PRBCs), mortality, and major adverse events (MAEs).

RESULTS

There were 189 patients (51%) treated for PRAs and 181 patients (49%) treated for TAAAs. IOBS was used in 194 patients (52%) and transfusion of PRBCs was needed in 137 (37%). Thirty-day mortality was 2.2% (8/370) and MAEs occurred in 123 patients (33%), including 74 patients (20%) who had EBL > 1L. EBL > 1L and transfusion of PRBCs were significantly higher (P < 0.05) in patients treated in the first half of clinical experience and in those with larger aneurysms, iliofemoral conduits, bilateral open surgical femoral access and Extent I-III TAAAs. Use of DrySeal^® sheaths (WL Gore, Flagstaff AZ) was associated with significantly lower (P < .05) EBL volume and with less transfusion of PRBCs. On multivariate analysis PRBCs > 1L, male gender and the last half of clinical experience were associated with MAEs/mortality.

CONCLUSIONS

F-BEVAR was associated with significantly higher volume of blood loss and transfusion requirements in patients treated in the early experience and in those who had iliofemoral conduits, open femoral surgical exposure or Extent I-III TAAAs.

Predictors and Outcomes of Cardiac Events following Thoracic Endovascular Aortic Repair in Descending Thoracic Aortic Aneurysm and Dissection

BACKGROUND

 Cardiac events following thoracic endovascular aortic repair (TEVAR) have been associated with significant morbidity and mortality. However, predictors of post-TEVAR cardiac events in descending thoracic aortic aneurysm or dissection are poorly understood.

METHODS

 A retrospective analysis of completed TEVAR procedures performed from 2010 to 2016 was conducted using the ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) participant user file database. Adult patients (≥18 years) who underwent TEVAR for descending thoracic aortic aneurysm or dissection were identified and 30-day outcomes were examined. An initial univariate analysis was performed to determine associations between all patient variables and cardiac events, defined as myocardial infarction or cardiac arrest that occurred ≤30 days of surgery. Multivariate logistic regression was subsequently performed to identify independent risk factors for cardiac events following TEVAR.

RESULTS

 The study identified 150 out of 2,905 (5.2%) patients who underwent TEVAR for descending thoracic aortic aneurysm or dissection who developed cardiac events. No significant difference in incidence of cardiac events was noted among patients presenting with aortic aneurysm or dissection (p = 0.339). The overall 30-day mortality rate for all patients was 9.1%. Independent preoperative predictors of post-TEVAR cardiac events included emergency procedure (odds ratio [OR] 2.80, 95% confidence interval [CI] 1.9-4.1, p < 0.01); American Society of Anesthesiologists score >3 (OR 1.71, 95% CI 1.1-2.6, p = 0.01), ventilator dependence (OR 2.33, 95% CI 1.3-4.2, p < 0.01), renal failure (OR 2.53, 95% CI 1.50-4.3, p < 0.01), blood transfusion (OR 1.84, 95% CI 1.1-3.2, p = 0.03), and preoperative leukocytosis (OR 2.45, 1.6-3.8, p < 0.01). After TEVAR, unplanned reintubation (OR 5.52, 95% CI 3.5-8.8, p < 0.01), prolonged mechanical ventilation (OR 1.94, 95% CI 1.2-3.2, p = 0.011), and postoperative blood transfusion (OR 4.02, 95% CI 2.70-6.0, p < 0.01) were independent predictors of cardiac events. Cardiac events greatly increased mortality (60.7 vs. 5.5%), total length of hospital stay (13.2 ± 14.7 days vs. 8.3 ± 9.3 days), and readmission rates (19.3 vs. 8.2%, p < 0.01).

CONCLUSIONS

 Cardiac events following TEVAR are associated with significant mortality. Patients with these risk factors should be appropriately monitored to improve outcomes.

The Interplay between Preoperative Anemia and Postoperative Blood Transfusion on Survival following Fenestrated Aortic Aneurysm Repair

BACKGROUND

Anemia is associated with a higher mortality following standard endovascular aortic repair (EVAR). This study evaluates the impact of anemia on fenestrated endovascular aneurysm repair (FEVAR) for complex aneurysm (AAA) repair.

METHODS

All elective FEVARs performed between 2010 and 2018 at a tertiary vascular center were analyzed. Anemia was defined as a preoperative hemoglobin (Hb) of <120 g/L for women and <130 g/L for men (World Health Organization definition). Primary outcome was overall survival by Kaplan-Meier. Secondary outcomes included length of hospital stay (LOS) and myocardial infarction (MI). Cox proportional hazard analyses were conducted.

RESULTS

In total, 132 FEVAR patients were followed up for 3.7 (2.2) years. Thirty-eight patients were anemic [average Hb of 112 (13) g/L]. Groups were comparable for age, AAA diameter, body mass index, and comorbidity. Anemic patients had a lower baseline estimated glomerular filtration rate [64.1 (23.2) vs. 70.9 (18.8) mL/min/1.73 m², P = 0.022] and a longer procedural time [242 (103) vs. 195.4 (88) min, P = 0.009] with no difference in the number of fenestrations (P = 0.696). Kaplan-Meier analysis demonstrated a higher mortality (log-rank P = 0.03) with 40% deceased versus 21% nonanemic (P = 0.04) at the end of follow-up. Anemic patients had more postoperative myocardial infarctions (MIs) (4 vs. 2, P = 0.037) and a longer LOS [9.2 (7.1) vs. 6.3 (6.8) days, P = 0.001]. Increasing Hb increased the likelihood of survival [hazard ratio, HR -0.8 (0.65-0.94), P = 0.038]. Postoperative transfusion was adversely associated with survival [HR 3.65 (1.05-12.8), P = 0.043].

CONCLUSIONS

Anemia appears to be associated with an increased rate of postoperative MI, LOS, frequency of blood transfusion, and mortality rate following FEVAR but this surpassed by postoperative blood transfusion. Optimization of preoperative Hb should be considered as a potential target for improvements in clinical outcomes and hypothetically a consequential reduction in postoperative red blood cell transfusion need.

Relationship between intra-operative hypotension and post-operative complications in traumatic hip surgery

Background and Aims:

The relationship between intra-operative hypotension and post-operative complications has been recently studied in non-cardiac surgery. Little is known about this relationship in traumatic hip surgery. Our study aimed to investigate this relationship.

Methods:

A retrospective study was conducted on patients who underwent surgical correction of traumatic hip fracture between 2010 and 2015. We reviewed the perioperative blood pressure readings and the episodes of intra-operative hypotension. Hypotension was defined as ≥30% decrease in the pre-induction systolic blood pressure sustained for ≥10 min. The relationship between intra-operative hypotension and post-operative complications was evaluated. Post-operative complications were defined as new events or diseases that required post-operative treatment for 48 h. Factors studied included type of anaesthesia, blood transfusion rate, pre-operative comorbidities and delay in surgery. We used the Statistical Package for Social Sciences (SPSS, IBM 25) to perform descriptive and non-parametric statistics.

Results:

A total of 502 patients underwent various types of traumatic hip surgery during the study period. Intra-operative hypotension developed in 91 patients (18.1%) and 42 patients (8.4%) developed post-operative complications. Significantly more patients with hypotension developed post-operative complications compared to patients with stable vitals (18.7% vs. 6.1; P < 0.001). There was no statistically significant difference in the incidence of post-operative complication in patients receiving general or spinal anaesthesia. Pre-operative comorbidities had no significant relationship with post-operative complications. Intra-operative blood transfusion was related to both intra-operative hypotension and post-operative complications.

Conclusion:

There was an association between intra-operative hypotension and post-operative complications in patients undergoing traumatic hip surgery.

Transfusion Timing and Postoperative Myocardial Infarction and Death in Patients Undergoing Common Vascular Procedures

BACKGROUND

Perioperative allogenic blood transfusions, specifically packed red bloods cells (pRBC), after vascular surgery procedures are modifiable risk factors that are associated with increased cardiovascular events and 30-day mortality. The aim of this study is to evaluate the effect of transfusion timing (intraoperative vs. postoperative) on the rate of postoperative myocardial infarction (POMI) and death.

METHODS

Six surgical and endovascular modules within the Vascular Quality Initiative (VQI) from 2013 to 2017 were reviewed at a single institution. Transfusion data on elective and urgent cases were abstracted and all patients who underwent inpatient procedures had routine postoperative troponin/ECG testing. The primary endpoint was POMI utilizing the American Heart Association's third universal definition for myocardial infarction. These criteria include the detection of a rise/and or fall of cTnT with at least one value above the 99th percentile and with at least one of the following 1) symptoms of acute myocardial ischemia, 2) new ischemic ECG changes, 3) development of pathological Q waves, 4) imaging evidence of new loss of viable myocardium or new regional wall motion abnormality in a pattern consistent with ischemic etiology. The secondary endpoint was 30-day all-cause mortality. Multivariable logistic regression analysis was utilized to evaluate the risk of transfusions on POMI and death.

RESULTS

We identified 1,154 cases for analysis (299 abdominal aortic aneurysm [EVAR], 117 infrainguinal bypasses, 127 open abdominal aortic aneurysm [AAA], 41 suprainguinal bypasses, 168 thoracic endovascular aortic repair [TEVAR], and 402 peripheral vascular interventions). Overall, the POMI rate was 2% and mortality 1%. Rates of POMI differed by procedure type (P = 0.04), where infrainguinal bypass had the highest rate of POMI at 4%. Death rates did not vary by type of procedure (P = 0.89). Mean number of intraoperative pRBC and postoperative pRBC transfusion was higher for patients with POMI (intraop: 1.3 vs. 0.3, postop: 1.8 vs. 0.4, both P < 0.01) and death (intraop: 1.4 vs. 0.3, postop: 2.5 vs. 0.4, both P < 0.01). In addition, older age and coronary artery disease (CAD) were associated with POMI on univariate analysis. On multivariable analysis for POMI, CAD (odds ratio [OR] = 5.15, 95% confidence interval [CI] [2.00-13.24], P < 0.001), receiving both an intraoperative and postoperative transfusion (OR = 6.20, 95% CI [1.78-21.55], P < 0.01) as well as a postoperative transfusion only (OR = 5.70, 95% CI [1.81-17.94], P < 0.01) compared to no transfusion were associated with higher odds of POMI; however intraoperative transfusion only was not (OR = 3.42, 95% CI [0.88-13.31], P = 0.08). On multivariable analysis, increasing age of the patient was associated with higher odds of death (OR = 1.08, 95% CI [1.01-1.15], P = 0.02) and statin use was highly protective (OR = 0.27, 95% CI [0.10-0.74], P = 0.01), but any intraoperative or postoperative transfusion compared to no transfusion was not associated with death after adjustment.

CONCLUSIONS

In our series with routine postoperative troponin screening in the inpatient setting, the use of an isolated postoperative transfusion as well as cases requiring both an intraoperative and postoperative transfusion was associated with POMI. However, isolated intraoperative transfusion was not associated with POMI, and we did not identify an association of transfusion with 30-day mortality. These data suggest that the perioperative setting of transfusions is important in its impact on postoperative outcomes and needs to be accounted for when evaluating transfusion outcomes and indications.

Red blood cell transfusion associated with increased morbidity and mortality in patients undergoing elective open abdominal aortic aneurysm repair

BACKGROUND

Red blood cell (RBC) transfusions are associated with increased mortality and morbidity. The aim of this analysis was to examine the association between RBC transfusions and long-term survival for patients undergoing elective open infrarenal abdominal aortic aneurysm (AAA) repair with up to 15 years of follow-up.

METHODS

Prospective cohort study using data from The Danish Vascular Registry from 2000-2015. Primary endpoint was all-cause mortality. Secondary endpoints were in-hospital complications. Transfused patients were divided into subgroups based on received RBC transfusions (1, 2-3, 4-5 or > 5). Using Cox regression multi-adjusted analysis, non-transfused patients were compared to transfused patients (1, 2-3, 4-5, >5 transfusions) for both primary and secondary endpoints.

RESULTS

There were 3 876 patients included with a mean survival of 9.1 years. There were 801 patients who did not receive transfusions. Overall 30-day mortality was 3.1% (121 patients) and 3.6% (112) for all transfused patients. For the five subgroups 30-day mortality was: No transfusions 1.1% (9 patients), 1 RBC 1.2% (4 patients), 2-3 RBC 2.2% (26 patients), 4-5 RBC 1.9% (14 patients) and > 5 RBC 7.9% (68 patients). After receiving RBCs, the hazard ratio for death was 1.54 (95% CI 1.27-1.85) compared to non-transfused patients. There was a significant increase in mortality when receiving 2-3 RBC: HR 1.32 (95% CI 1.07-1.62), 4-5 RBC: 1.64 (1.32-2.03) and >5 RBC: 1.96 (1.27-1.85) in a multi-adjusted model.

CONCLUSION

There is a dose-dependent association between RBC transfusions received during elective AAA repair and an increase in short- and long-term mortality. Approximately 25% of included patients had preoperative anemia. These findings should raise awareness regarding potentially unnecessary and harmful RBC transfusions.

Predictors of bleeding or anemia requiring transfusion in complex endovascular aortic repair and its impact on outcomes in health insurance claims

OBJECTIVE

This study aimed to determine predictors and outcomes associated with bleeding or anemia requiring transfusion (BAT) after fenestrated or branched endovascular aneurysm repair (FB-EVAR).

METHODS

Health insurance claims data of Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate BAT in elective FB-EVAR performed between 2008 and 2017. International Classification of Diseases and German Operations and Procedure Key codes were used.

RESULTS

A total of 959 patients (24.8% with BAT) matching the inclusion criteria were identified during the study period. Compared with patients without BAT, patients with BAT were older (74.4 vs 73.0 years; P = .015) and suffered more frequently from congestive heart failure (18.5% vs 9.4%), cardiac arrhythmias (26.9% vs 14.7%), and hereditary or acquired coagulopathy (31.9% vs 6.2%; all P < .001). Coagulopathy (odds ratio [OR], 3.65; 95% confidence interval [CI], 2.29-5.84), female sex (OR, 2.67; 95% CI, 1.78-4.00), and multiple comorbidities (OR, 1.10; 95% CI, 1.07-1.14) were independent predictors of BAT (all P < .001). BAT was associated with higher in-hospital (11.3% vs 2.6%), 30-day (12.2% vs 3.1%), and 90-day (18.5% vs 4.4%) mortality (all P < .001). Furthermore, myocardial infarction (23.9% vs 2.8%) and paraplegia (9.7% vs 0.7%) were more frequent in the BAT group (all P < .001). In multivariable analyses, BAT was associated with worse short-term (OR, 3.19; 95% CI, 1.63-6.33; P = .001) and long-term survival (hazard ratio, 1.62; 95% CI, 1.24-2.11; P < .001).

CONCLUSIONS

Patients with hereditary or acquired coagulopathy, patients with multiple comorbidities, and women are at higher risk for development of BAT after FB-EVAR. The occurrence of this event was strongly associated with higher major complication rates and worse short-term and long-term survival. This emphasizes a need to further illuminate the value of patient blood management in FB-EVAR.

A model-based cost-effectiveness analysis of Patient Blood Management

BACKGROUND

Patient blood management (PBM) is a multidisciplinary concept focused on the management of anaemia, minimisation of iatrogenic blood loss and rational use of allogeneic blood products. The aims of this study were: (i) to analyse post-operative outcome in patients with liberal vs restrictive exposure to allogeneic blood products and (ii) to evaluate the cost-effectiveness of PBM in patients undergoing surgery.

MATERIALS AND METHODS

A systematic literature review and meta-analysis were performed to compare post-operative complications in predominantly non-transfused patients (restrictive transfusion group) and patients who received one to three units of red blood cells (liberal transfusion group). Outcome measures included sepsis with/without pneumonia, acute renal failure, acute myocardial infarction and acute stroke. In a second step, a health economic model was developed to calculate cost-effectiveness of PBM (PBM-arm vs control-arm) for simulated cohorts of 10,000 cardiac and non-cardiac surgical patients based on the results of the meta-analysis and costs.

RESULTS

Out of 478 search results, 22 studies were analysed in the meta-analysis. The pooled relative risk of any complication in the restrictive transfusion group was 0.43 for non-cardiac and 0.34 for cardiac surgical patients. In the simulation model, PBM was related to reduced complications (1,768 vs 1,245) and complication-related deaths (411 vs 304) compared to standard care. PBM-related costs of therapy exceeded costs of the control arm by € 150 per patient. However, total costs, including hospitalisation, were higher in the control-arm for both non-cardiac (€ 2,885.11) and cardiac surgery patients (€ 1,760.69). The incremental cost-effectiveness ratio including hospitalisation showed savings of € 30,458 (non-cardiac and cardiac surgery patients) for preventing one complication and € 128,023 (non-cardiac and cardiac surgery patients) for prevention of one complication-related death in the PBM-arm.

DISCUSSION

Our results indicate that PBM may be associated with fewer adverse clinical outcomes compared to control management and may, thereby, be cost-effective.

Perioperative red blood cell transfusion in orofacial surgery

In the field of orofacial surgery, a red blood cell transfusion (RBCT) is occasionally required during double jaw and oral cancer surgery. However, the question remains whether the effect of RBCT during the perioperative period is beneficial or harmful. The answer to this question remains challenging. In the field of orofacial surgery, transfusion is performed for the purpose of oxygen transfer to hypoxic tissues and plasma volume expansion when there is bleeding. However, there are various risks, such as infectious complications (viral and bacterial), transfusion-related acute lung injury, ABO and non-ABO associated hemolytic transfusion reactions, febrile non-hemolytic transfusion reactions, transfusion associated graft-versus-host disease, transfusion associated circulatory overload, and hypersensitivity transfusion reaction including anaphylaxis and transfusion-related immune-modulation. Many studies and guidelines have suggested RBCT is considered when hemoglobin levels recorded are 7 g/dL for general patients and 8-9 g/dL for patients with cardiovascular disease or hemodynamically unstable patients. However, RBCT is occasionally an essential treatment during surgeries and it is often required in emergency cases. We need to comprehensively consider postoperative bleeding, different clinical situations, the level of intra- and postoperative patient monitoring, and various problems that may arise from a transfusion, in the perspective of patient safety. Since orofacial surgery has an especially high risk of bleeding due to the complex structures involved and the extensive vascular distribution, measures to prevent bleeding should be taken and the conditions for a transfusion should be optimized and appropriate in order to promote patient safety.

Risk Factors Associated with Perioperative Myocardial Infarction in Major Open Vascular Surgery

BACKGROUND

Among patients undergoing noncardiac surgery, major vascular surgery is associated with a high risk of perioperative myocardial infarction (MI). Currently, there are no perioperative MI risk calculators accounting for intraoperative and postoperative risk factors in vascular surgery patients. We aimed to investigate specific risk factors for perioperative MI after major open vascular surgery to determine which patients are at highest risk of MI and the association of perioperative MI with perioperative transfusion.

METHODS

This statewide, retrospective cohort study analyzed risk factors for perioperative MI in major open vascular surgery between July 2012 and December 2015 using the Michigan Surgical Quality Collaborative, a multicenter quality collaborative. Patients were identified using current procedure terminology codes including open abdominal aortic aneurysm repairs (oAAA), aortobifemoral bypasses (AFB), and lower extremity bypasses (LEB). Rates of myocardial infarction were described for each procedure. A priori, preoperative, intraoperative, and postoperative variables were evaluated using univariate and multivariable statistics after adjusting for intraoperative factors including anesthesia type, intraoperative blood loss, intraoperative transfusion, and intraoperative vasopressor medications.

RESULTS

A total of 3,689 patients underwent major open vascular surgery, including 375 oAAA, 392 AFB, and 2,922 LEB procedures. The overall incidence of MI was 2.4%, varying from 1.8% for aortobifemoral bypass, 2.4% for lower extremity bypass, and 3.7% for open abdominal aortic aneurysm repair. Although preoperative risk factors for myocardial infarction included age, American Society of Anesthesiologists score, diabetes, coronary artery disease, congestive heart failure, use of beta blocker, lower preoperative hematocrit, and surgical priority (urgent/emergent cases), after adjusting for intraoperative risk factors, all preoperative risk factors were not significant with the exception of surgical priority. After adjusting for intraoperative factors, only surgical priority (odds ratio [OR] = 1.70, 95% confidence interval [CI] [1.01-2.85], P < 0.001) and postoperative transfusion (OR = 2.65, 95% CI [1.59-4.44], P < 0.001) was associated with myocardial infarction, and higher nadir hematocrit was inversely associated with myocardial infarction (OR = 0.89, 95% CI [0.85-0.94], P < 0.001).

CONCLUSIONS

Among vascular surgery patients undergoing major open vascular surgery, surgical priority was the only preoperative risk factors independently associated with MI, and only postoperative variables such as nadir hematocrit and postoperative transfusion were associated with MI. This suggests minimizing intraoperative blood loss and prioritizing early intraoperative transfusion may be the potential targets for process improvement.

Low vs. high haemoglobin trigger for transfusion in vascular surgery: protocol for a randomised trial

BACKGROUND

In patients with cardiovascular disease, guidelines for administration of red blood cells (RBC) are mainly based on studies outside the vascular surgical setting with the recommendation to use a haemoglobin (hb) trigger-level lower than by guidelines from The European Society for Vascular Surgery. Restricting RBC transfusion may affect blood O₂ transport with a risk for development of tissue ischaemia and postoperative complications.

METHODS

In a single-centre, open-label, assessor blinded trial, 58 vascular surgical patients (> 40 years of age) awaiting open surgery of the infrarenal aorta or infrainguinal arterial bypass surgery undergo a web-based randomisation to one of two groups: perioperative RBC transfusion triggered by hb < 8 g/dl or hb < 9.7 g/dl. Administration of fluid follows an individualised strategy by optimising cardiac stroke volume and near-infrared spectroscopy determines tissue oxygenation. Serious adverse event rates are: myocardial injury (troponin-I ≥ 45 ng/l or ischaemic electrocardiographic findings at day 30), acute kidney injury, death, stroke and severe transfusion reactions. A follow-up visit takes place 30 days after surgery and a follow-up of serious adverse events in the Danish National Patient Register within 90 days is pending.

DISCUSSION

This trial is expected to determine whether a RBC transfusion triggered by hb < 9.7 g/dl compared with hb < 8 g/dl results in adequate separation of postoperative hb levels, transfusion of more RBC units and maintains a higher tissue oxygenation. The results will inform the design of a multicentre trial for evaluation of important postoperative outcomes.

Preoperative anemia is associated with mortality after carotid endarterectomy in symptomatic patients

OBJECTIVE

Preoperative anemia and blood transfusions are associated with worse outcomes after surgery. However, the impact of preoperative anemia and transfusions on outcomes after carotid endarterectomy (CEA) is unknown.

METHODS

CEA patients from 2011 to 2015 in the American College of Surgeons National Surgical Quality Improvement Program Targeted Vascular module were compared by the presence of preoperative anemia (hematocrit <36%) after stratification by symptom status. Multivariable analysis accounted for differences in baseline characteristics. We included an interaction term in our multivariable model to assess whether the effect of anemia differed significantly between patients who received a perioperative transfusion and those who did not, with 30-day mortality as our primary outcome.

RESULTS

Of 16,068 patients, 6734 (42%) were symptomatic, of whom 1500 (22%) had anemia. Of the 9334 asymptomatic patients, 1935 (21%) had anemia. Both symptomatic and asymptomatic anemic patients were more likely to be transfused perioperatively compared with nonanemic patients, with 7.0% vs 0.4%, and 5.8% vs 0.7% (both P < .001). Among symptomatic patients, those with anemia compared with those without had a higher rate of 30-day mortality (2.5% vs 0.7%; P < .001). After adjustment, anemic symptomatic patients had a higher 30-day mortality risk (odds ratio [OR], 3.1; 95% confidence interval [CI], 1.9-5.0; P < .001) compared with nonanemic symptomatic patients. In addition, in symptomatic patients, we found a significant interaction between anemia and perioperative transfusion on the outcome of 30-day mortality (P = .004), with a higher risk in perioperatively transfused symptomatic patients with anemia (OR, 7.8; 95% CI, 3.4-18.0; P < .001) than in symptomatic patients with anemia who did not receive a perioperative transfusion (OR, 2.3; 95% CI, 1.4-3.9; P = .002). In asymptomatic patients, anemic and nonanemic patients had comparable 30-day mortality rates (0.9% vs 0.6%; P = .2). After adjustment, anemia was not associated with 30-day mortality in asymptomatic patients (OR, 1.0; 95% CI, 0.5-2.0; P = .9), nor did we identify an interaction between anemia and perioperative transfusion in asymptomatic patients (P = .1). Patients who received a preoperative transfusion had a higher 30-day mortality rate than anemic patients not receiving preoperative transfusion in both symptomatic (n = 31, 9.7% vs 2.5%; P = .04) and asymptomatic patients (n = 21, 9.5% vs 0.9%; P = .02).

CONCLUSIONS

Preoperative anemia is a risk factor for 30-day mortality after CEA in symptomatic patients but not in asymptomatic patients. These results should be factored into the selection of symptomatic patients for CEA and dissuade treatment of asymptomatic patients scheduled for CEA who need a preoperative transfusion.

Variation in Transfusion Practices and the Association with Perioperative Adverse Events in Patients Undergoing Open Abdominal Aortic Aneurysm Repair and Lower Extremity Arterial Bypass in the Vascular Quality Initiative

BACKGROUND

Blood transfusions are associated with adverse events. We examined perioperative transfusion practices and associated complications following open vascular procedures nationwide in the Vascular Quality Initiative (VQI).

METHODS

Adults undergoing open abdominal aortic aneurysm repair (OAR) and lower extremity arterial bypass (Bypass) within VQI (2003-2016) were identified. All emergent cases, patients with preoperative hemoglobin <7 g/dL, preoperative hospitalization >1 day, or a return to operating room during the index hospitalization were excluded. Units of red blood cells transfused were the primary outcome. Secondary outcomes were postoperative myocardial infarction (MI) and death. Patient, center, and procedural factors were evaluated. Multivariable mixed effects negative binomial regression and multivariable logistic regression were performed.

RESULTS

We identified 24,131 procedures (OAR 3885, 16.1%; Bypass 20,246, 83.9%) among 22,532 patients (10.1% had >1 procedure). Overall, 37.5% of OAR and 19.5% of Bypass were transfused. Transfusion rates varied across estimated blood loss quartiles and across various preoperative hemoglobin levels. The overall rate of postoperative MI and death was 4.0% and 1.8% for OAR, and 2.2% and 0.7% for Bypass, respectively. In univariate and multivariable analysis, transfusions were associated with an increased risk of postoperative MI and death. A mixed effects negative binomial model demonstrated variation in transfusions across centers (P < 0.001). Female gender and preoperative anemia were significantly associated with transfusions.

CONCLUSIONS

Blood transfusions are variable across centers in VQI. Transfusions are associated with a higher postoperative MI and death after OAR and Bypass. Efforts to reduce transfusion may focus on center variability, gender, and preoperative anemia.

Are we cross-matching too much blood for elective open abdominal aortic aneurysm repair?

OBJECTIVES

This study aims to identify current blood transfusion requirements in elective open abdominal aortic aneurysm repair and to compare this to an existing maximum surgical blood order schedule.

METHODS

We retrospectively identified patients who underwent elective open abdominal aortic aneurysm repair over a 40-month period in our institution. Pre-operative number of units cross-matched and the number of units actually transfused were identified. The cross-match to transfusion ratio was then calculated.

RESULTS

Blood transfusion at any time post-operatively was required in 23 (48.9%) cases. Patients needing an intra-operative blood transfusion had a median of 2 units. Of the pre-operative cross-matched units (123), only 43 were used, giving a cross-match to transfusion ratio of 2.86.

CONCLUSION

Our current maximum surgical blood order schedule is poorly followed and a cross-match to transfusion ratio of 2.86 indicates we are cross-matching too many units for elective open abdominal aortic aneurysm repair. A carefully considered individualised management of blood products, with the requirement of at least a valid group and save sample, may be more appropriate.

Manubrium-limited ministernotomy versus conventional sternotomy for aortic valve replacement (MAVRIC): study protocol for a randomised controlled trial

Background

Aortic valve replacement is one of the most common cardiac surgical procedures performed worldwide. Conventional aortic valve replacement surgery is performed via a median sternotomy; the sternum is divided completely from the sternal notch to the xiphisternum. Minimally invasive aortic valve replacement, using a new technique called manubrium-limited ministernotomy, divides only the manubrium from the sternal notch to 1 cm below the manubrio-sternal junction.

More than one third of patients undergoing conventional sternotomy develop clinically significant bleeding requiring post-operative red blood cell transfusion. Case series data suggest a potentially clinically significant difference in red blood cell transfusion requirements between the two techniques. Given the implications for National Health Service resources and patient outcomes, a definitive trial is needed.

Methods/design

This is a single-centre, single-blind, randomised controlled trial comparing aortic valve replacement surgery using manubrium-limited ministernotomy (intervention) and conventional median sternotomy (usual care). Two hundred and seventy patients will be randomised in a 1:1 ratio between the intervention and control arms, stratified by baseline logistic EuroSCORE and haemoglobin value. Patients will be followed for 12 weeks from discharge following their index operation. The primary outcome is the proportion of patients who receive a red blood cell transfusion post-operatively within 7 days of surgery. Secondary outcomes include red blood cell and blood product transfusions, blood loss, re-operation rates, sternal wound pain, quality of life, markers of inflammatory response, hospital discharge, health care utilisation, cost and cost effectiveness and adverse events.

Discussion

This is the first trial to examine aortic valve replacement via manubrium-limited ministernotomy versus conventional sternotomy when comparing red blood cell transfusion rates following surgery. Surgical trials present significant challenges; strengths of this trial include a rigorous research design, standardised surgery performed by experienced consultant cardiothoracic surgeons, an agreed anaesthetic regimen, patient blinding and consultant-led patient recruitment. The MAVRIC trial will demonstrate that complex surgical trials can be delivered to exemplary standards and provide the community with the knowledge required to inform future care for patients requiring aortic valve replacement surgery.

Trial registration

International Standard Randomised Controlled Trial Number (ISRCTN) ISRCTN29567910. Registered on 3 February 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1768-4) contains supplementary material, which is available to authorized users.

Independent risk factors for hypoxemia after surgery for acute aortic dissection

Objectives:

To determine risk factors associated with postoperative hypoxemia after surgery for acute type A aortic dissection.

Methods:

We retrospectively analyzed the clinical data of 192 patients with acute type A aortic dissection who underwent surgery in Qingdao Municipal Hospital, Medical College of Qingdao University, Qingdao, China between January 2007 and December 2013. Patients were divided into hypoxemia group (n=55) [arterial partial pressure of oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) ≤200 mm Hg] and non-hypoxemia group (n=137) [PaO₂/FiO₂ >200 mm Hg]. Perioperative clinical data were analyzed and compared between the 2 groups.

Results:

The incidence of postoperative hypoxemia after surgery for acute aortic dissection was 28.6% (55/192). Perioperative death occurred in 13 patients (6.8%). Multivariate regression identified body mass index (BMI) >25 kg/m² (OR=21.929, p=0.000), deep hypothermic circulatory arrest (DHCA) (OR=11.551, p=0.000), preoperative PaO₂/FiO₂ ≤300 mm Hg (OR=7.830, p=0.000) and blood transfusion >6U in 24 hours postoperatively (OR=12.037, p=0.000) as independent predictors of postoperative hypoxemia for patients undergoing Stanford A aortic dissection surgery.

Conclusion:

Our study demonstrated that BMI >25 kg/m², DHCA, preoperative PaO₂/FiO₂ ≤300 mm Hg, and blood transfusion in 24 hours postoperatively >6U were independent risk factors of the hypoxemia after acute type A aortic dissection aneurysm surgery.

The Association of Peri-Procedural Blood Transfusion with Morbidity and Mortality in Patients Undergoing Percutaneous Lower Extremity Vascular Interventions: Insights from BMC2 VIC

Objective

To determine the predictors of periprocedural blood transfusion and the association of transfusion on outcomes in high risk patients undergoing endoluminal percutaneous vascular interventions (PVI) for peripheral arterial disease.

Methods/Results

Between 2010–2014 at 47 hospitals participating in a statewide quality registry, 4.2% (n = 985) of 23,273 patients received a periprocedural blood transfusion. Transfusion rates varied from 0 to 15% amongst the hospitals in the registry. Using multiple logistic regression, factors associated with increased transfusion included female gender (OR = 1.9; 95% CI: 1.6–2.1), low creatinine clearance (1.3; 1.1–1.6), pre-procedural anemia (4.7; 3.9–5.7), family history of CAD (1.2; 1.1–1.5), CHF (1.4; 1.2–1.6), COPD (1.2; 1.1–1.4), CVD or TIA (1.2; 1.1–1.4), renal failure CRD (1.5; 1.2–1.9), pre-procedural heparin use (1.8; 1.4–2.3), warfarin use (1.2; 1.0–1.5), critical limb ischemia (1.7; 1.5–2.1), aorta-iliac procedure (1.9; 1.5–2.5), below knee procedure (1.3; 1.1–1.5), urgent procedure (1.7; 1.3–2.2), and emergent procedure (8.3; 5.6–12.4). Using inverse weighted propensity matching to adjust for confounders, transfusion was a significant risk factor for death (15.4; 7.5–31), MI (67; 29–150), TIA/stroke (24; 8–73) and ARF (19; 6.2–57). A focused QI program was associated with a 28% decrease in administration of blood transfusion (p = 0.001) over 4 years.

Conclusion

In a large statewide PVI registry, post procedure transfusion was highly correlated with a specific set of clinical risk factors, and with in-hospital major morbidity and mortality. However, using a focused QI program, a significant reduction in transfusion is possible.

Excessive intravenous fluid therapy in head and neck cancer surgery

BACKGROUND

The purpose of this retrospective study was to present our assessment of modifiable perioperative factors for major cardiac and cerebrovascular events (MACCE).

METHODS

This study included an unselected cohort of patients with head and neck cancer (n = 456) treated in Turku University Hospital between 1999 and 2008.

RESULTS

Perioperative and postoperative univariate predictors of MACCE at 30-day follow-up were: total amount of fluids (during 24 hours) over 4000 mL, any red blood cell (RBC) infusion, treatment in the intensive care unit (ICU), tracheostomy, and microvascular reconstruction surgery. Median time from operation to MACCE was 3 days. Patients receiving >4000 mL of fluids had MACCE more often compared with those receiving <4000 mL (10.8% vs 2.4%; p < .001, respectively). Moreover, every RBC unit transfused or every liter of fluid administered over 4000 mL/24h increased the risk of MACCE 18% per unit/liter, respectively.

CONCLUSION

Patients with head and neck cancer receiving excessive intravenous fluid administration perioperatively and postoperatively are at high risk for cardiac complications, especially heart failure. © 2016 Wiley Periodicals, Inc. Head Neck 39: 37-41, 2017.

Continuous noninvasive hemoglobin monitoring: ready for prime time?

PURPOSE OF REVIEW

Determination of hemoglobin (Hb) concentration is essential for the detection of anemia and hemorrhage and is widely used to evaluate a patient for a possible blood transfusion. Although commonly accepted as intrinsic to the process, traditional laboratory measurements of Hb are invasive, intermittent, and time-consuming. Noninvasive Hb (NIHb)-monitoring devices have recently become available and promise the potential for detecting sudden changes in a patient's Hb level. In addition to reduced delays in clinical intervention, these devices also allow for a reduction in patient discomfort, infection risk, required personnel, and long-term costs. Unfortunately, it has been shown that many clinical factors can influence their accuracy.

RECENT FINDINGS

Many studies have been published on the accuracy and precision of NIHb-monitoring devices in various clinical settings. A recent meta-analysis has shown a small mean difference but wide limits of agreement between NIHb and laboratory measurements, indicating that caution should be used by physicians when making clinical decisions based on this device.

SUMMARY

NIHb measurements may currently be considered to be a supplemental tool for monitoring trends in Hb concentration, but are not currently developed enough to replace an invasive approach. Moreover, further studies are still required before implementing NIHb in the clinical decision-making process. Specifically, no studies have demonstrated that this technology improves clinical outcomes or patient safety.

Preoperative antiplatelet and statin treatment was not associated with reduced myocardial infarction after high-risk vascular operations in the Vascular Quality Initiative

OBJECTIVE

Medical management with antiplatelet (AP) and statin therapy is recommended for nearly all patients undergoing vascular surgery to reduce cardiovascular events. We assessed the association between preoperative use of AP and statin medications and postoperative in-hospital myocardial infarction (MI) in patients undergoing high-risk open surgery.

METHODS

We studied patients who underwent elective suprainguinal (n = 3039) and infrainguinal (n = 8323) bypass and open infrarenal abdominal aortic aneurysm repair (n = 3007) in the Vascular Quality Initiative (VQI, 2005-2014). We assessed the association between AP or statin use and in-hospital postoperative MI and MI/death. Multivariable logistic analyses were performed to identify the patient, procedure, and preoperative medication factors associated with postoperative MI and MI/death across procedures and patient cardiac risk strata. Secondary end points included bleeding, transfusion, and thrombotic complications.

RESULTS

Most patients were taking both AP and statin preoperatively (56% both agents vs 19% AP only, 13% statin only, and 12% neither agent). Use of both agents was more common for patients in the highest cardiac risk stratum (low, 54%; intermediate, 59%; high, 61%; P < .01). Increased cardiac risk was associated with higher MI rates (1.8% vs 3.8% vs 6.5% for low, intermediate, and high risk; P < .01). By univariate analysis, MI rate was paradoxically higher for patients taking both agents (3.7%, vs statin only 2.8%, AP only 2.6%, or neither AP nor statin 2.4%; P = .003). After multivariable adjustment, rates of MI in patients taking preoperative AP only (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.7-1.2) and statin only (OR, 0.8; 95% CI, 0.6-1.2) were not different from those in patients taking either or neither medication (neither agent compared with taking both agents: OR, 1.0; 95% CI, 0.7-1.4; P > .05 for all). Similarly, rates of MI/death were not associated with medication status after multivariable adjustment. Estimated blood loss >1 liter (OR, 2.4; 95% CI, 1.6-3.7; P < .01) and transfusions of 1 or 2 units (OR, 2.5; 95% CI, 2.0-3.3; P < .01) and ≥3 units (OR, 4.0; 95% CI, 3.1-5.3; P < .01) were highly associated with MI, with similar findings related to composite MI/death in multivariable analysis. Rates of blood loss were slightly higher with AP use for all procedures; however, increased transfusions occurred only for infrainguinal bypass with AP use. Rates of reoperation for bleeding, graft thrombosis, or graft revision did not differ by preoperative AP use.

CONCLUSIONS

Preoperative AP and statin medications as used in VQI were not associated with the rate of in-hospital MI/death after major open vascular operations. Rather, predicted cardiac risk and operative blood loss were significantly associated with in-hospital MI or MI/death. AP and statin medications appear to be more useful in reducing late mortality than early postoperative MI/death in VQI. However, they were not harmful, so their long-term benefit argues for continued use.

Hospital Blood Transfusion Patterns During Major Noncardiac Surgery and Surgical Mortality

We retrospectively examined intraoperative blood transfusion patterns at US veteran's hospitals through description of national patterns of intraoperative blood transfusion by indication for transfusion in the elderly; assessment of temporal trends in the use of intraoperative blood transfusion; and relationship of institutional use of intraoperative blood transfusion to hospital 30-day risk-adjusted postoperative mortality rates.Limited data exist on the pattern of intraoperative blood transfusion by indication for transfusion at the hospital level, and the relationship between intraoperative transfusion rates and institutional surgical outcomes.Using the Department of Veterans Affairs Surgical Quality Improvement Program database, we assigned 424,015 major noncardiac operations among elderly patients (≥65 years) in 117 veteran's hospitals, from 1997 to 2009, into groups based on indication for intraoperative blood transfusion according to literature and clinical guidelines. We then examined institutional variations and temporal trends in surgical blood use based on these indications, and the relationship between these institutional patterns of transfusion and 30-day postoperative mortality.Intraoperative transfusion occurred in 38,056/424,015 operations (9.0%). Among the 64,390 operations with an indication for transfusion, there was wide variation (median: 49.9%, range: 8.7%-76.2%) in hospital transfusion rates, a yearly decline in transfusion rates (average 1.0%/y), and an inverse relationship between hospital intraoperative transfusion rates and hospital 30-day risk-adjusted mortality (adjusted mortality of 9.8 ± 2.8% vs 8.3 ± 2.1% for lowest and highest tertiles of hospital transfusion rates, respectively, P = 0.02). In contrast, for the 225,782 operations with no indication for transfusion, there was little variation in hospital transfusion rates (median 0.7%, range: 0%-3.4%), no meaningful temporal change in transfusion (average 0.0%/y), and similar risk-adjusted 30-day mortality across all tertiles of hospital transfusion rates.Among patients ≥65 years with an indication for intraoperative transfusion, intraoperative transfusion patterns varied widely across hospitals and declined through the 1997 to 2009 study period. Hospitals with higher transfusion rates in these patients have lower risk-adjusted 30-day postoperative mortality rates.