Variation in triggers and use of perioperative blood transfusion in major gastrointestinal surgery

Preoperative anemia: impact on short- and long-term outcomes following curative-intent resection of gastroenteropancreatic neuroendocrine tumors

BACKGROUND

The effect of preoperative anemia on clinical outcomes of patients undergoing resection of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has not been previously investigated. This study aimed to characterize how preoperative anemia affected short- and long-term outcomes of patients undergoing curative-intent resection of GEP-NETs.

METHODS

Patients who underwent curative-intent resection for GEP-NETs between January 1990 and December 2020 were identified from 8 major institutions. The last preoperative hemoglobin level was recorded; anemia was defined as <13.5 g/dL in males or <12.0 g/dL in females based on the guides of the American Society of Hematology. The effect of anemia on postoperative outcomes was assessed on uni- and multivariate analyses.

RESULTS

Among 1559 patients, the median age was 58 years (IQR, 48-66), and roughly one-half of the cohort was male (796 [51.1%]). Most patients had a pancreatic tumor (1040 [66.7%]), followed by small bowel (259 [16.6%]), duodenum (103 [6.6%]), stomach (66 [4.2%]), appendix (53 [3.4%]), and other locations (38 [2.6%]). The median preoperative hemoglobin level was 13.4 g/dL (IQR, 12.2-14.5). Overall, 101 (6.7%) and 119 (8.5%) patients received an intra- or postoperative packed red blood cell (pRBC) transfusion, respectively. A total of 972 patients (44.5%) experienced a postoperative complication. Although the overall incidence of complications was no different among patients who did (anemic: 48.7%) vs patients who did not (nonanemic: 47.3%) have anemia (P = .597), patients with preoperative anemia were more likely to develop a major (Clavien-Dindo grade ≥IIIa: 48.9% [anemic] vs 38.0% [nonanemic]; P = .006) and multiple (≥3 types of complications: 32.2% [anemic] vs 19.7% [anemic]; P < .001) complications. Of note, 1-, 3-, and 5-year overall survival (OS) rates were 96.7%, 90.5%, and 86.6%, respectively. On multivariable analysis, anemia (hazard ratio, 2.0; 95% CI, 1.2-3.2; P = .006) remained associated with worse OS; postoperative pRBC transfusion was associated with an OS (5-year OS: 75.0% vs 87.7%; P = .017) and recurrence-free survival (RFS; 5-year RFS: 66.9% vs 76.5%; P = .047).

CONCLUSION

Preoperative anemia was commonly identified in roughly 1 in 3 patients who underwent curative-intent resection for GEP-NETs. Preoperative anemia was strongly associated with a higher risk of postoperative morbidity and worse long-term outcomes.

Nonclinical factors affecting intraoperative red blood cell transfusion: a systematic review

PURPOSE

There is significant variability in intraoperative red blood cell (RBC) transfusion practice. We aimed to use the theoretical domains framework (TDF) to categorize nonclinical and behavioural factors driving intraoperative RBC transfusion practice in a systematic review of the literature.

SOURCE

We searched electronic databases from inception until August 2021 to identify studies evaluating nonclinical factors affecting intraoperative RBC transfusion. Using the Mixed Methods Appraisal Tool, we assessed the quality of included studies and identified relevant nonclinical factors, which were coded into TDF domains by two independent reviewers using NVivo (Lumivero, QSR International, Burlington, MA, USA). We identified common themes within domains and sorted domains based on the frequency of reported factors.

PRINCIPAL FINDINGS

Our systematic review identified 18 studies: nine retrospective cohort studies, six cross-sectional surveys, and three before-and-after studies. Factors related to the social influences, behavioural regulation, environmental context/resources, and beliefs about consequences domains of the TDF were the most reported factors. Key factors underlying the observed variability in transfusion practice included the social effects of peers, patients, and institutional culture on decision-making (social influences), and characteristics of the practice environment including case volume, geographic location, and case start time (environmental context/resources). Studies reported variable beliefs about the consequences of both intraoperative transfusion and anemia (beliefs about consequences). Provider- and institutional-level audits, educational sessions, and increased communication between surgeons/anesthesiologists were identified as strategies to optimize intraoperative transfusion decision-making (behavioural regulation).

CONCLUSION

Our systematic review has synthesized the literature on nonclinical and behavioural factors impacting intraoperative transfusion decision-making, categorized using the TDF. These findings can inform evidence-based interventions to reduce intraoperative RBC transfusion variability.

STUDY REGISTRATION

Open Science Framework ( https://osf.io/pm8zs/?view_only=166299ed28964804b9360c429b1218c1 ; first posted, 3 August 2022).

Point-of-care haemoglobin accuracy and transfusion outcomes in non-cardiac surgery at a Canadian tertiary academic hospital: protocol for the PREMISE observational study

INTRODUCTION

Transfusions in surgery can be life-saving interventions, but inappropriate transfusions may lack clinical benefit and cause harm. Transfusion decision-making in surgery is complex and frequently informed by haemoglobin (Hgb) measurement in the operating room. Point-of-care testing for haemoglobin (POCT-Hgb) is increasingly relied on given its simplicity and rapid provision of results. POCT-Hgb devices lack adequate validation in the operative setting, particularly for Hgb values within the transfusion zone (60-100 g/L). This study aims to examine the accuracy of intraoperative POCT-Hgb instruments in non-cardiac surgery, and the association between POCT-Hgb measurements and transfusion decision-making.

METHODS AND ANALYSIS

PREMISE is an observational prospective method comparison study. Enrolment will occur when adult patients undergoing major non-cardiac surgery require POCT-Hgb, as determined by the treating team. Three concurrent POCT-Hgb results, considered as index tests, will be compared with a laboratory analysis of Hgb (lab-Hgb), considered the gold standard. Participants may have multiple POCT-Hgb measurements during surgery. The primary outcome is the difference in individual Hgb measurements between POCT-Hgb and lab-Hgb, primarily among measurements that are within the transfusion zone. Secondary outcomes include POCT-Hgb accuracy within the entire cohort, postoperative morbidity, mortality and transfusion rates. The sample size is 1750 POCT-Hgb measurements to obtain a minimum of 652 Hgb measurements <100 g/L, based on an estimated incidence of 38%. The sample size was calculated to fit a logistic regression model to predict instances when POCT-Hgb are inaccurate, using 4 g/L as an acceptable margin of error.

ETHICS AND DISSEMINATION

Institutional ethics approval has been obtained by the Ottawa Health Science Network-Research Ethics Board prior to initiating the study. Findings from this study will be published in peer-reviewed journals and presented at relevant scientific conferences. Social media will be leveraged to further disseminate the study results and engage with clinicians.

Outcomes following perioperative red blood cell transfusion in patients undergoing elective major abdominal surgery: a systematic review and meta-analysis

BACKGROUND

Perioperative red blood cell transfusion is a double-edged sword for surgical patients. While transfusion of red cells can increase oxygen delivery by increasing haemoglobin levels, its impact on short- and long-term postoperative outcomes, particularly in patients undergoing elective major abdominal surgery, is unclear.

METHODS

We conducted a systematic review and meta-analysis on the effect of perioperative blood transfusions on postoperative outcomes in elective major abdominal surgery. PubMed, Cochrane, and Scopus databases were searched for studies with data collected between January 1, 2000 and June 6, 2020. The primary outcome was short-term mortality, including all-cause 30-day or in-hospital mortality. Secondary outcomes included long-term all-cause mortality, any morbidity, infectious complications, overall survival, and recurrence-free survival. No randomised controlled trials were found. Thirty-nine observational studies were identified, of which 37 were included in the meta-analysis.

RESULTS

Perioperative blood transfusion was associated with short-term all-cause mortality (odds ratio [OR] 2.72, 95% confidence interval [CI] 1.89-3.91, P<0.001), long-term all-cause mortality (hazard ratio 1.35, 95% CI 1.09-1.67, P=0.007), any morbidity (OR 2.18, 95% CI 1.81-2.64, P<0.001), and infectious complications (OR 1.90, 95% CI 1.60-2.26, P<0.001). Perioperative blood transfusion remained associated with short-term mortality in the sensitivity analysis after excluding studies that did not control for preoperative anaemia (OR 2.27, 95% CI 1.59-3.24, P<0.001).

CONCLUSIONS

Perioperative blood transfusion in patients undergoing elective major abdominal surgery is associated with poorer short- and long-term postoperative outcomes. This highlights the need to implement patient blood management strategies to manage and preserve the patient's own blood and reduce the need for red blood cell transfusion.

TRIAL REGISTRATION

PROSPERO (CRD42021254360).

Intraoperative Blood Management Strategies for Patients Undergoing Noncardiac Surgery: The Ottawa Intraoperative Transfusion Consensus

Importance

There is marked variability in red blood cell (RBC) transfusion during the intraoperative period. The development and implementation of existing clinical practice guidelines have been ineffective in reducing this variability.

Objective

To develop an internationally endorsed consensus statement about intraoperative transfusion in major noncardiac surgery.

Evidence Review

A Delphi consensus survey technique with an anonymous 3-round iterative rating and feedback process was used. An expert panel of surgeons, anesthesiologists, and transfusion medicine specialists was recruited internationally. Statements were informed by extensive preparatory work, including a systematic reviews of intraoperative RBC guidelines and clinical trials, an interview study with patients to explore their perspectives about intraoperative transfusion, and interviews with physicians to understand the various behaviors that influence intraoperative transfusion decision-making. Thirty-eight statements were developed addressing (1) decision-making (interprofessional communication, clinical factors, procedural considerations, and audits), (2) restrictive transfusion strategies, (3) patient-centred considerations, and (4) research considerations (equipoise, outcomes, and protocol suspension). Panelists were asked to score statements on a 7-point Likert scale. Consensus was established with at least 75% agreement.

Findings

The 34-member expert panel (14 of 33 women [42%]) included 16 anesthesiologists, 11 surgeons, and 7 transfusion specialists; panelists had a median of 16 years' experience (range, 2-50 years), mainly in Canada (52% [17 of 33]), the US (27% [9 of 33]), and Europe (15% [5 of 33]). The panel recommended routine preoperative and intraoperative discussion between surgeons and anesthesiologists about intraoperative RBC transfusion as well as postoperative review of intraoperative transfusion events. Point-of-care hemoglobin testing devices were recommended for transfusion guidance, alongside an algorithmic transfusion protocol with a restrictive hemoglobin trigger; however, more research is needed to evaluate the use of restrictive triggers in the operating room. Expert consensus recommended a detailed preoperative consent discussion with patients of the risks and benefits of both anemia and RBC transfusion and routine disclosure of intraoperative transfusion. Postoperative morbidity and mortality were recommended as the most relevant outcomes associated with intraoperative RBC transfusion, and transfusion triggers of 70 and 90 g/L were considered acceptable hemoglobin triggers to evaluate restrictive and liberal transfusion strategies, respectively, in clinical trials.

Conclusions and Relevance

This consensus statement offers internationally endorsed expert guidance across several key domains on intraoperative RBC transfusion practice for noncardiac surgical procedures for which patients are at medium or high risk of bleeding. Future work should emphasize knowledge translation strategies to integrate these recommendations into routine clinical practice and transfusion research activities.

Variation in Anesthesiology Provider-Volume for Complex Gastrointestinal Cancer Surgery: A Population-Based Study

OBJECTIVE

Examine between-hospital and between-anesthesiologist variation in anesthesiology provider-volume (PV) and delivery of high-volume anesthesiology care.

BACKGROUND

Better outcomes for anesthesiologists with higher PV of complex gastrointestinal cancer surgery have been reported. The factors linking anesthesiology practice and organization to volume are unknown.

METHODS

We identified patients undergoing elective esophagectomy, hepatectomy, and pancreatectomy using linked administrative health data sets (2007-2018). Anesthesiology PV was the annual number of procedures done by the primary anesthesiologist in the 2 years before the index surgery. High-volume anesthesiology was PV>6 procedures/year. Funnel plots to described variation in anesthesiology PV and delivery of high-volume care. Hierarchical regression models examined between-anesthesiologist and between-hospital variation in delivery of high-volume care use with variance partition coefficients (VPCs) and median odds ratios (MORs).

RESULTS

Among 7893 patients cared for at 17 hospitals, funnel plots showed variation in anesthesiology PV (median ranging from 1.5, interquartile range: 1-2 to 11.5, interquartile range: 8-16) and delivery of HV care (ranging from 0% to 87%) across hospitals. After adjustment, 32% (VPC 0.32) and 16% (VPC: 0.16) of the variation were attributable to between-anesthesiologist and between-hospital differences, respectively. This translated to an anesthesiologist MOR of 4.81 (95% CI, 3.27-10.3) and hospital MOR of 3.04 (95% CI, 2.14-7.77).

CONCLUSIONS

Substantial variation in anesthesiology PV and delivery of high-volume anesthesiology care existed across hospitals. The anesthesiologist and the hospital were key determinants of the variation in high-volume anesthesiology care delivery. This suggests that targeting anesthesiology structures of care could reduce variation and improve delivery of high-volume anesthesiology care.

Factors Associated with Perioperative Transfusions in Veterans

Background: Private sector literature demonstrates an association between perioperative transfusions and poor clinical outcomes. Hemostatic agents, surgeon training, and patient blood management programs (PBMPs) may mitigate perioperative bleeding. This study attempts to identify preoperative risk factors associated with perioperative transfusions in Veterans. Study Design and Methods: This study is a retrospective review of the prospectively maintained Veterans Affairs Surgical Quality Improvement Project database. Included patients were older than 18 years and underwent noncardiac surgery between April 1, 2016, and March 31, 2021. Data collected included demographics, surgery variables, preoperative clinical variables, postoperative outcomes, and perioperative transfusions. Cohorts were created based on transfusion status. Univariate and multivariate analyses were performed to characterize the similarities, differences, and potential predictors of perioperative transfusion. Results: Of 6108 patients included, 153 patients received perioperative transfusions. The risks for transfusion included older age, male sex, black race, smoking, and low body mass index (BMI). The highest percent of transfused patients underwent vascular (43.4%), orthopedic (22%), and general surgeries (20%). Transfusion increased risk for postoperative cerebral vascular accident (P = .041) and 30-day mortality (P < .001). Multivariate regression analysis revealed American Society of Anesthesiology class, chemotherapy within 30 days, increased age, tobacco smoking, and decreased BMI were predictive of perioperative transfusions. Discussion: Perioperative transfusions are associated with increased morbidity and mortality in the Veteran population. These retrospective data describe the complex relationships between perioperative transfusions and outcomes after noncardiac surgery. These results serve as a foundation to create predictive models and PBMP within the veteran population to decrease transfusion requirements and associated complications.

The Association Between Hospital High-volume Anesthesiology Care and Patient Outcomes for Complex Gastrointestinal Cancer Surgery: A Population-based Study

OBJECTIVE

To examine the association of between hospital rates of high-volume anesthesiology care and of postoperative major morbidity.

BACKGROUND

Individual anesthesiology volume has been associated with individual patient outcomes for complex gastrointestinal cancer surgery. However, whether hospital-level anesthesiology care, where changes can be made, influences the outcomes of patients cared at this hospital is unknown.

METHODS

We conducted a population-based retrospective cohort study of adults undergoing esophagectomy, pancreatectomy, or hepatectomy for cancer from 2007 to 2018. The exposure was hospital-level adjusted rate of high-volume anesthesiology care. The outcome was hospital-level adjusted rate of 90-day major morbidity (Clavien-Dindo grade 3-5). Scatterplots visualized the relationship between each hospital's adjusted rates of high-volume anesthesiology and major morbidity. Analyses at the hospital-year level examined the association with multivariable Poisson regression.

RESULTS

For 7893 patients at 17 hospitals, the rates of high-volume anesthesiology varied from 0% to 87.6%, and of major morbidity from 38.2% to 45.4%. The scatter plot revealed a weak inverse relationship between hospital rates of high-volume anesthesiology and of major morbidity (Pearson: -0.23). The adjusted hospital rate of high-volume anesthesiology was independently associated with the adjusted hospital rate of major morbidity (rate ratio: 0.96; 95% CI, 0.95-0.98; P <0.001 for each 10% increase in the high-volume rate).

CONCLUSIONS

Hospitals that provided high-volume anesthesiology care to a higher proportion of patients were associated with lower rates of 90-day major morbidity. For each additional 10% patients receiving care by a high-volume anesthesiologist at a given hospital, there was an associated reduction of 4% in that hospital's rate of major morbidity.

Understanding Intraoperative Transfusion Decision-Making Variability: A Qualitative Study

There is evidence of significant intraoperative red blood cell (RBC) transfusion variability that cannot be explained by case-mix, and may reflect unwarranted transfusions. The objective was to explore the source of intraoperative RBC transfusion variability by eliciting the beliefs of anesthesiologists and surgeons that underlie transfusion decisions. Interviews based on the Theoretical Domains Framework were conducted to identify beliefs about intraoperative transfusion. Content analysis was performed to group statements into domains. Relevant domains were selected based on frequency of beliefs, perceived influence on transfusion, and the presence of conflicting beliefs within domains. Of the 28 transfusion experts recruited internationally (16 anesthesiologists, 12 surgeons), 24 (86%) were Canadian or American and 11 (39%) identified as female. Eight relevant domains were identified: (1) Knowledge (insufficient evidence to guide intraoperative transfusion), (2) Social/professional role and identity (surgeons/anesthesiologists share responsibility for transfusions), (3) Beliefs about consequences (concerns about morbidity of transfusion/anemia), (4) Environmental context/resources (transfusions influenced by type of surgery, local blood supply, cost of transfusion), (5) Social influences (institutional culture, judgment by peers, surgeon-anesthesiologist relationship, patient preference influencing transfusion decisions), (6) Behavioral regulation (need for intraoperative transfusion guidelines, usefulness of audits and educational sessions to guide transfusion), (7) Nature of the behaviors (overtransfusion remains commonplace, transfusion practice becoming more restrictive over time), and (8) Memory, attention, and decision processes (various patient and operative characteristics are incorporated into transfusion decisions). This study identified a range of factors underlying intraoperative transfusion decision-making and partly explain the variability in transfusion behavior. Targeted theory-informed behavior-change interventions derived from this work could help reduce intraoperative transfusion variability.

Intraoperative Blood Loss Estimation in Hepato-pancreato-biliary Surgery- Relevant, Not Reported, Not Standardized: Results From a Systematic Review and a Worldwide Snapshot Survey

OBJECTIVE

To provide an overview of the current practice of intraoperative blood loss (BL) estimation in hepato-pancreato-biliary (HPB) surgery.

BACKGROUND

Intraoperative BL is a major quality marker in HPB surgery and a predictor of perioperative outcomes. However, the method for BL estimation is not standardized.

METHODS

A systematic review was performed of original studies published between 2006 and 2021 reporting the intraoperative BL of patients undergoing pancreatic or hepatic resections. A web-based snapshot survey was distributed globally to all members of the International Hepato-Pancreato-Biliary Association (IHPBA).

RESULTS

A total of 806 studies were included; 480 (60%) had BL as their primary outcome, and 105 (13%) had BL as their secondary outcome. However, 669 (83%) did not specify how BL estimation was performed, and 9 different methods were found among the remaining 136 (17%) studies.The survey was completed by 252 surgeons. Most of the responders (94%) declared that they systematically performed BL estimation and considered BL predictive of postoperative complications after pancreatic (73%) and liver (74%) resection. All methods previously identified in the literature were used by responders with different frequencies. A calculation based on suction fluid amounts, operative gauze weight, and irrigation was the most used method in the literature (7%) and among responders (51%). Most responders (83%) felt that BL estimation in HPB surgery needs improved standardization.

CONCLUSIONS

Standardization of intraoperative BL estimation is urgently needed in HPB surgery to ensure the consistency of reporting and reproducibility.

Predictors of 90-day morbidity and mortality after Frey procedure for chronic pancreatitis

BACKGROUND

The literature on predictors for postoperative complications after Frey procedure (FP) is sparse. The aim of this study is to report our experience with 90-day complications of FP and predictors for complications.

METHODS

All patients with chronic pancreatitis (CP), who underwent a FP between August 2007 and July 2021, were retrospectively reviewed. Univariate and multivariate analysis were used to identify predictors of 90-day morbidity and mortality.

RESULTS

Of the total 270 patients, 84 (31%) patients developed at least one postoperative complication. Major complications occurred in 32 (12%) patients. Most common complication was wound infection and it was significantly more common in stented patients (p = 0.017). Pancreatic fistula and post pancreatectomy hemorrhage (PPH) developed in 7.4% of patients. Thirteen patients (4.8%) required early re-operation and the most common cause of re-exploration was PPH. 90-day mortality was 1% (n = 3) and all 3 patients required re-exploration for PPH. Median postoperative hospital stay was 9 (5-51) days. Perioperative blood transfusions was the only independent predictor of postoperative complications after FP.

CONCLUSIONS

Frey procedure is an acceptable treatment modality with low rates of mortality and reasonable perioperative morbidities. Minimizing blood transfusions may further improve 90-day outcomes.

Preoperative hemoglobin levels, extended resections and the body mass index influence survival after pancreaticoduodenectomy

PURPOSE

The negative influence of perioperative transfusion of packed red blood cells on the prognosis of various malignancies is the focus of recent research interest. The development of a propensity score for the prediction of perioperative transfusion of packed red blood cells (pRBCs) and the identification of independent risk factors for survival, that can either be known prior to or during surgery in patients undergoing pancreaticoduodenectomy for pancreatic head cancer are the two objectives of this study.

METHODS

Logistic regression analyses and Cox regression modeling were used to identify independent risk factors for perioperative transfusion of pRBCs and to determine individual risk factors for patient survival. A total of 101 adult patients who underwent surgery between 01/01/2016 and 12/31/2020 were investigated in a single-center retrospective analysis.

RESULTS

Preoperative hemoglobin levels (OR: 0.472, 95%-CI: 0.312-0.663, p < 0.001) and extended resections (OR: 4.720, 95%-CI: 1.819-13.296, p = 0.001) were identified as independent risk factors for perioperative transfusion of pRBCs, enabling the prediction of pRBC transfusion with high sensitivity and specificity (AUROC: 0.790). The logit of the derived propensity model for the transfusion of pRBCs (HR: 9.231, 95%CI: 3.083-28.118, p < 0.001) and preoperative Body Mass Index (BMI) (HR, 0.925; 95%-CI: 0.870-0.981, p = 0.008) were independent risk factors for survival.

CONCLUSIONS

Low preoperative hemoglobin levels, low BMI values, and extended resections are significant risk factors for survival that can be known and thus potentially be influenced prior to or during surgery. Patient blood management programs and prehabilitation programs should strive to increase preoperative hemoglobin levels and improve preoperative malnutrition.

Patient perspectives on intraoperative blood transfusion: A qualitative interview study with perioperative patients

BACKGROUND

While red blood cell (RBC) transfusions are frequently administered during surgery, little is known about patient perspectives regarding intraoperative transfusion. The aim of this study was to understand patient perspectives about intraoperative RBC transfusion and explore their willingness to engage in transfusion prevention strategies.

STUDY DESIGN AND METHODS

This descriptive qualitative study used semi-structured patient interviews before and after surgery. Purposive sampling was used to select adult patients with varying perioperative courses, including having perioperative transfusion or postoperative anemia. Inductive and deductive thematic analyses were conducted to identify themes.

RESULTS

Twenty patients (nine preoperative and 11 postoperative patients) were interviewed. The following themes were identified: Risk-benefit perception of transfusion, transfusion acceptance, trust, patient involvement in transfusion decisions, acceptance of transfusion prevention interventions, and communication. Patients perceived transfusions as low-risk compared to the surgery itself. Factors influencing transfusion acceptance included trust in the healthcare system and the perception of the treatability of transfusion-related complications. Some patients preferred to defer transfusion decision making to the perioperative team, citing trust in professional judgment and building a positive relationship with their surgeon. Others wished for their preferences to be incorporated into transfusion decisions. Some desired detailed blood consent conversations and most were willing to participate in strategies to reduce intraoperative transfusion.

CONCLUSION

In our sample, patients consider intraoperative transfusions as low-risk high-reward interventions and trust the healthcare system and perioperative team to guide intraoperative transfusion decision making. However, preoperative transfusion consent discussions were recalled as being superficial and lacking nuance. Targeted strategies are required to improve blood consent discussions to better integrate patient preferences.

Generating real-world evidence compatible with evidence from randomized controlled trials: a novel observational study design applicable to surgical transfusion research

BACKGROUND

Numerous observational studies have revealed an increased risk of death and complications with transfusion, but this observation has not been confirmed in randomized controlled trials (RCTs). The "transfusion kills patients" paradox persists in real-world observational studies despite application of analytic methods such as propensity-score matching. We propose a new design to address this long-term existing issue, which if left unresolved, will be deleterious to the healthy generation of evidence that supports optimized transfusion practice.

METHODS

In the new design, we stress three aspects for reconciling observational studies and RCTs on transfusion safety: (1) re-definition of the study population according to a stable hemoglobin range (gray zone of transfusion decision; 7.5-9.5 g/dL in this study); (2) selection of comparison groups according to a trigger value (last hemoglobin measurement before transfusion; nadir during hospital stay for control); (3) dealing with patient heterogeneity according to standardized mean difference (SMD) values. We applied the new design to hospitalized older patients (aged ≥60 years) undergoing general surgery at four academic/teaching hospitals. Four datasets were analyzed: a base population before (Base Match-) and after (Base Match+) propensity-score matching to simulate previous observational studies; a study population before (Study Match-) and after (Study Match+) propensity-score matching to demonstrate effects of our design.

RESULTS

Of 6141 older patients, 662 (10.78%) were transfused and showed high heterogeneity compared with those not receiving transfusion, particularly regarding preoperative hemoglobin (mean: 11.0 vs. 13.5 g/dL) and intraoperative bleeding (≥500 mL: 37.9% vs. 2.1%). Patient heterogeneity was reduced with the new design; SMD of the two variables was reduced from approximately 100% (Base Match-) to 0% (Study Match+). Transfusion was related to a higher risk of death and complications in Base Match- (odds ratio [OR], 95% confidence interval [CI]: 2.68, 1.86-3.86) and Base Match+ (2.24, 1.43-3.49), but not in Study Match- (0.77, 0.32-1.86) or Study Match+ (0.66, 0.23-1.89).

CONCLUSIONS

We show how choice of study population and analysis could affect real-world study findings. Our results following the new design are in accordance with relevant RCTs, highlighting its value in accelerating the pace of transfusion evidence generation and generalization.

A Systematic Review and Meta-analysis of Randomized Controlled Trials Comparing Intraoperative Red Blood Cell Transfusion Strategies

OBJECTIVE

The objective of this work was to carry out a meta-analysis of RCTs comparing intraoperative RBC transfusion strategies to determine their impact on postoperative morbidity, mortality, and blood product use.

SUMMARY OF BACKGROUND DATA

RBC transfusions are common in surgery and associated with widespread variability despite adjustment for casemix. Evidence-based recommendations guiding RBC transfusion in the operative setting are limited.

METHODS

The search strategy was adapted from a previous Cochrane Review. Electronic databases were searched from January 2016 to February 2021. Included studies from the previous Cochrane Review were considered for eligibility from before 2016. RCTs comparing intraoperative transfusion strategies were considered for inclusion. Co-primary outcomes were 30-day mortality and morbidity. Secondary outcomes included intraoperative and perioperative RBC transfusion. Meta-analysis was carried out using random-effects models.

RESULTS

Fourteen trials (8641 patients) were included. One cardiac surgery trial accounted for 56% of patients. There was no difference in 30-day mortality [relative risk (RR) 0.96, 95% confidence interval (CI) 0.71-1.29] and pooled postoperative morbidity among the studied outcomes when comparing restrictive and liberal protocols. Two trials reported worse composite outcomes with restrictive triggers. Intraoperative (RR 0.53, 95% CI 0.43-0.64) and perioperative (RR 0.70, 95% CI 0.62-0.79) blood transfusions were significantly lower in the restrictive group compared to the liberal group.

CONCLUSIONS

Intraoperative restrictive transfusion strategies decreased perioperative transfusions without added postoperative morbidity and mortality in 12/14 trials. Two trials reported worse outcomes. Given trial design and generalizability limitations, uncertainty remains regarding the safety of broad application of restrictive transfusion triggers in the operating room. Trials specifically designed to address intraoperative transfusions are urgently needed.

Transfusion Requirements and Blood Bank Support in Heart and Lung Transplantation

OBJECTIVE

Transplantations may require massive transfusion of blood products. Therefore, blood banks need to predict, prepare, and supply the required amount of blood products.

METHODS

We measured the volume of transfused blood components as red blood cells, fresh frozen plasma, platelets, and cryoprecipitate in 54 and 89 patients who received heart and lung transplantation, respectively, in our hospital between January 2012 and December 2019.

RESULTS

Platelets were the most frequently transfused blood component. Transfusion volumes during heart and lung transplantation surgeries differed: red blood cells, 7.83 units vs 14.84 units; fresh frozen plasma, 2.67 units vs 12.29 units; platelets, 13.13 units vs 23.63 units; and cryoprecipitate, 1.74 units vs 2.57 units; respectively. The average transfusion volume of transplants was different each year.

CONCLUSION

Periodic evaluation of transfusion requirements will facilitate the efficient management of blood products at the time of transplantation and help blood banks predict changes in blood requirements.

Mortality and clinical outcome of Italian patients undergoing orthopaedic surgery: effect of peri-operative blood transfusion

BACKGROUND

Blood transfusion is a relevant issue for elderly and frail patients, as they are often anaemic and have chronic diseases. Transfusion of red blood cells (RBC) can potentially affect morbidity and mortality of elderly patients undergoing major orthopaedic surgery.

MATERIALS AND METHODS

We carried out a retrospective analysis of 2,593 patients undergoing major orthopaedic surgery between 2013 and 2017 in a single research institution in the Region of Apulia. The aims of the study were: 1) to describe the characteristics of transfused patients according to a restrictive or liberal strategy of transfusion and haemoglobin (Hb) triggers and targets; 2) to investigate the effect of RBC transfusion on mortality and complications.

RESULTS

Older, women and patients with American Society of Anesthesiologists (ASA) score 3-4 were more often transfused. Those with lower admission Hb level had a higher risk of being transfused. Hb triggers were associated with the patients' age. A restrictive transfusion strategy was significantly more frequent in patients undergoing primary knee replacement and in those with higher estimated blood loss. We did not observe any significant difference of complications in patients transfused with a liberal vs restrictive strategy. Logistic regression correcting for potential confounders revealed that sex (males more than females), duration of stay in hospital, hip fracture and Charlson score >4 were good predictors of complications and/or mortality. Mortality was significantly higher in males and in older patients with ASA score 3-4.

DISCUSSION

In this large cohort of Italian patients undergoing major orthopaedic surgery males were significantly more exposed than women to complications and in-hospital mortality. Furthermore, those undergoing urgent surgery because of hip fracture had a 3-fold higher chance of complications. Charlson score >4 and ASA 3-4 are good predictors of complications and mortality, respectively.

Intraoperative Red Blood Cell Transfusion Decision-making: A Systematic Review of Guidelines

OBJECTIVES

The objective of this work was to carry out a systematic review of clinical practice guidelines (CPGs) pertaining to intraoperative red blood cell (RBC) transfusions, in terms of indications, decision-making, and supporting evidence base.

SUMMARY OF BACKGROUND DATA

RBC transfusions are common during surgery and there is evidence of wide variability in practice.

METHODS

Major electronic databases (MEDLINE, EMBASE, and CINAHL), guideline clearinghouses and Google Scholar were systematically searched from inception to January 2019 for CPGs pertaining to indications for intraoperative RBC transfusion. Eligible guidelines were retrieved and their quality assessed using AGREE II. Relevant recommendations were abstracted and synthesized to allow for a comparison between guidelines.

RESULTS

Ten guidelines published between 1992 and 2018 provided indications for intraoperative transfusions. No guideline addressed intraoperative transfusion decision-making as its primary focus. Six guidelines provided criteria for transfusion based on hemoglobin (range 6.0-10.0 g/dL) or hematocrit (<30%) triggers. In the absence of objective transfusion rules, CPGs recommended considering other parameters such as blood loss (n = 7), signs of end organ ischemia (n = 5), and hemodynamics (n = 4). Evidence supporting intraoperative recommendations was extrapolated primarily from the nonoperative setting. There was wide variability in the quality of included guidelines based on AGREE II scores.

CONCLUSION

This review has identified several clinical practice guidelines providing recommendations for intraoperative transfusion. The existing guidelines were noted to be highly variable in their recommendations and to lack a sufficient evidence base from the intraoperative setting. This represents a major knowledge gap in the literature.

Declining Use of Red Blood Cell Transfusions for Gastrointestinal Cancer Surgery: A Population-Based Analysis

BACKGROUND

Gastrointestinal cancer surgery patients often develop perioperative anemia commonly treated with red blood cell (RBC) transfusions. Given the potential associated risks, evidence published over the past 10 years supports restrictive transfusion practices and blood conservation programs. Whether transfusion practices have changed remains unclear. We describe temporal RBC transfusion trends in a large North American population who underwent gastrointestinal cancer surgery.

METHODS

We conducted a population-based retrospective cohort study of patients who underwent gastrointestinal cancer resection between 2007 and 2018 using health administrative datasets. The outcome was RBC transfusion during hospitalization. Temporal transfusion trends were analyzed with Cochran-Armitage tests. Multivariable regression assessed the association between year of diagnosis and likelihood of RBC transfusion while controlling for confounding.

RESULTS

Of 79,764 patients undergoing gastrointestinal cancer resection, the median age was 69 years old (interquartile range (IQR) 60-78 years) and 55.5% were male. The most frequent procedures were colectomy (52.8%) and proctectomy (23.0%). A total of 18,175 patients (23%) received RBC transfusion. The proportion of patients transfused decreased from 26.5% in 2007 to 18.9% in 2018 (p < 0.001). After adjusting for patient, procedure, and hospital factors, the most recent time period (2015-2018) was associated with a reduced likelihood of receiving RBC transfusion [relative risk 0.86 (95% confidence interval: 0.83-0.89)] relative to the intermediate time period (2011-2014).

CONCLUSION

Over 11 years, we observed decreased RBC transfusion use and reduced likelihood of transfusion in patients undergoing gastrointestinal cancer resection. This information provides a foundation to further examine transfusion appropriateness or explore if additional transfusion minimization in surgical patients can be achieved.

Evaluation for Perioperative Blood Transfusion during Major Abdominal Procedures in a Pediatric Population: A Retrospective Observation Cohort Study

Objectives

The purpose of this study was to examine modifiable factors and their impact on perioperative blood transfusion for pediatric patients with major abdominal procedures.

Methods

This is a retrospective review of 1,506 patients who underwent major abdominal surgical procedures in a tertiary medical center from January 2008 to June 2018. Clinical data about blood administration including triggers and targets for intra- or postoperative transfusion were collected and analyzed. The inappropriate transfusion (transfusion > 8.0 g/dL of hemoglobin [Hb] trigger) and overtrans-fusion criteria (target transfusion > 10.0 g/dL or > 2 g/dL of target minus trigger level) were applied to examine the intraoperative factors with the intraoperative transfusion practice. Perioperative morbidity was further assessed based on the inappropriate transfusion and overtransfusion status.

Results

Intraoperative transfusion was used in 468 (31.1%) of the 1,506 patients included in the study. Among them, 212 (45.3%) intraoperative transfusion episodes were classified as inappropriate, and 135 cases (28.8%) were confirmed as overtransfusion. On univariate analysis, inappropriate transfusions were observed more commonly among patients with younger age (p < 0.001) and who underwent hepatic resection (p < 0.001) or intestinal resection (p < 0.001). Overtransfusion was also associated with elevated trigger of 8.0 g/dL Hb (p = 0.006) and younger age (p = 0.003). No perioperative complications were associated with inappropriate transfusions and overtransfusion under multivariate analysis.

Conclusions

Overtransfusion was common in hepatic resection and younger age, but to definitely prove this hypothesis, a prospective randomized trial needs to be performed.

Perioperative blood transfusions following hepatic lobectomy: A national analysis of academic medical centers in the modern era

BACKGROUND

The purpose of the study was to characterize the prevalence and impact of perioperative blood use for patients undergoing hepatic lobectomy at academic medical centers.

METHODS

The University HealthSystem Consortium (UHC) database was queried for hepatic lobectomies performed between 2011 and 2014 (n = 6476). Patients were grouped according to transfusion requirements into high (>5 units, 7%), medium (2-5 units, 6%), low (1 unit, 8%), and none (0 units, 79%) during hospital stay for comparison of outcomes.

RESULTS

Over 20% of patients undergoing hepatic lobectomy received blood perioperatively, of which 35% required more than 5 units. Patients with high transfusion requirements had increased severity of illness (p < 0.01). High transfusion requirements correlated with increased readmission rates (23.4% vs. 19.2% vs. 16.6% vs. 13.5%), total direct costs ($31,982 vs. $20,859 vs. $19,457 vs. $16,934), length of stay (9 days vs. 8 vs. 7 vs. 6), and in-hospital mortality (10.8% vs. 2.0% vs. 0.9% vs. 2.0%) compared to medium, low, and no transfusion amounts (all p < 0.01). Neither center nor surgeon volume were associated with transfusion use.

CONCLUSION

High transfusion requirements after hepatic lobectomy in the United States are associated with worse perioperative quality measures, but may not be influenced by center or surgeon volume.

Patient blood management for liver resection: consensus statements using Delphi methodology

BACKGROUND

Blood loss and transfusion remain a significant concern in liver resection (LR). Patient blood management (PBM) programs reduce use of transfusions and improve outcomes and costs, but are not standardized for LR. This study sought to create an expert consensus statement on PBM for LR using modified Delphi methodology.

METHODS

An expert panel representing hepato-biliary surgery, anesthesiology, and transfusion medicine was invited to participate. 28 statements addressing the 3 pillars of PBM were created. Panelists were asked to rate statements on a 7-point Likert scale. Three-rounds of iterative rating and feedback were completed anonymously, followed by an in-person meeting. Consensus was reached with at least 70% agreement.

RESULTS

The 35 experts panel recommended routine pre-operative transfusion risk assessment, and investigation and management of anemia with iron supplementation. Intra-operatively, restrictive fluid administration without routine central line insertion was recommended, along with intermittent hepatic pedicle occlusion and surgical techniques considerations. Specific criteria for restrictive intra-operative and post-operative transfusion strategy were recommended.

CONCLUSIONS

PBM for LR included medical and technical interventions throughout the perioperative continuum, addressing specificities of LR. Diffusion and adoption of these recommendations can standardize PBM for LR to improve patient outcomes and resource utilization.

Intraoperative but not postoperative blood transfusion adversely affect cancer recurrence and survival following nephrectomy for renal cell carcinoma

The association between perioperative blood transfusion (PBT) with adverse oncological outcomes have been previously reported in multiple malignancies including RCC. Nevertheless, the importance of transfusion timing is still unclear. The primary purpose of this study is to appraise whether the receipt of intraoperative blood transfusion (BT) differ from postoperative BT in regards to cancer outcomes in renal cell carcinoma (RCC) patients treated with nephrectomy. Data on 1168 patients with RCC, who underwent radical or partial nephrectomy as primary therapy between 1988–2013 were analyzed. PBT was defined as transfusion of allogeneic red blood cells (RBC) during surgery or the postsurgical period. Survival was analyzed and compared using the Kaplan–Meier method with the log-rank test. Of 1168 patients, 198 patients (16.9%) received a PBT. Including 117 intraoperative BT and 81 postoperative BT. Only 21 (10.6%) patients required both intraoperative and postoperative BT. On multivariate analyses, receipt of PBT was associated with significantly worse local disease recurrence (HR: 2.4; P = 0.017), metastatic progression (HR: 2.7; P = 0.005), cancer-specific mortality (HR: 3.5; P = 0.002) and all-cause mortality (HR: 2.1; P = 0.005). Nevertheless, postoperative BT was not independently associated with increased risk of local recurrence (p = 0.1), metastatic progression (P = 0.16) or kidney cancer death (P = 0.63), yet did significantly increase the risk of overall mortality (HR: 2.6; P = 0.004). In the current study, intraoperative transfusion of allogeneic RBC is associated with increased risks of cancer recurrence and mortality following nephrectomy.

Perioperative use of blood products is associated with risk of morbidity and mortality after surgery

BACKGROUND

Administration of blood products may be associated with increased morbidity and perioperative mortality in surgical patients.

METHODS

Patients aged 18 + who underwent gastrointestinal surgery at the Ohio State University Wexner Medical Center 9/10/2015-5/9/2018 were identified. Multivariable logistic regression models were used to evaluate impact of blood product use on survival and complications, as well as to identify factors associated with receipt of transfusions.

RESULTS

Among 10,756 patients, 35,517 units of blood products were transfused. Preoperative nadir hemoglobin was associated with receipt of blood product transfusion (OR 0.55, 95% CI 0.53, 0.68). After adjusting for patient and procedural characteristics, patients undergoing transfusion of blood products had an increased risk of perioperative mortality (OR 7.80, 95% CI 6.02, 10.10).

CONCLUSIONS

The use of blood products was associated with increased risk of complication and death. Patient blood management programs should be implemented to provide rational criteria and guidance for the transfusion of blood products.

Blood Transfusions in Major Pancreatic Surgery: A 10-Year Cohort Study Including 1404 Patients Undergoing Pancreatic Resections in Finland

Background:

Despite guidelines on blood transfusion (TF) thresholds, there seems to be great variation in transfusion policies between hospitals and surgeons. In order to improve and unify blood transfusion policies, the Finnish Red Cross Blood Service carried out a project concerning the optimal use of blood products (Verivalmisteiden optimaalinen käyttö) between 2002 and 2011. In this study, we determined the blood transfusion trends in major pancreatic surgery in Finland.

Methods:

Initially, 1337 patients who underwent major pancreatic resections between 2002 and 2011 were classified into the TF+ or TF− groups. Centers were divided into high-, medium-, and low-volume centers. The blood transfusion trends and the trigger points for blood transfusions in these patients were determined.

Results:

There were no differences between high-, medium- and low-volume centers in blood usage, trigger points or the use of reserved blood units after pancreatoduodenectomy or total pancreatectomy. However, the trigger points were lowered significantly during the study period at high-volume centers (p = 0.003), and a better use of reserved blood units was found in high- (p < 0.001) and medium-volume (p = 0.043) centers. In addition, a better use of reserved blood units was found in high-volume centers after distal pancreatectomy (p = 0.020)

Conclusion:

Although only minor changes in blood transfusion trends after pancreatoduodenectomy or total pancreatectomy were found generally, the lowering of the transfusion trigger point and the best use of reserved blood units during the study period occurred in high-volume centers.

Distinct risk factors for early and late blood transfusion following pancreaticoduodenectomy

BACKGROUND

The International Study Group of Pancreatic Surgery (ISGPS) has defined two periods of postpancreatectomy hemorrhage, early (<24 h) and late (>24 h). A previously published Blood Usage Risk Score (BURS) aimed to predict early and late blood transfusion. The primary aim of this study was to define risk factors for early and late blood transfusion after pancreaticoduodenectomy. Secondary aims were to assess the predictive accuracy of the BURS.

METHODS

In this retrospective observational study, multivariable analyses were used to identify independent risk factors for both early and late blood transfusion. The predictive ability of the BURS was then assessed using a receiver operating characteristic (ROC) curve analysis.

RESULTS

Among 628 patients, 99 (15.8%) and 144 (22.9%) received early and late blood transfusion, respectively. Risk factors for blood transfusion differed between early and late periods. Preoperative anemia and venous resection were associated with early blood transfusion whilst Whipple's resection (as opposed to pylorus preserving pancreaticoduodenectomy), lack of biliary stent and a narrow pancreatic duct were predictors of late blood transfusion. The BURS was significantly predictive of early blood transfusion, albeit with a modest degree of accuracy (AUROC: 0.700, P < 0.001), but not of late blood transfusion (AUROC: 0.525, P = 0.360). Late blood transfusion was independently associated with increasing severity of postoperative pancreatic fistula (POPF) (OR: 1.85, 3.18 and 9.97 for biochemical, types B and C POPF, respectively, relative to no POPF).

CONCLUSIONS

Two largely different sets of variables are related to early and late blood transfusion following pancreaticoduodenectomy. The BURS was significantly associated with early, albeit with modest predictive accuracy, but not late blood transfusion. An understanding of POPF risk allows assessment of the need for late blood transfusion.

Percentage change in hemoglobin level and morbidity in spine surgery patients

OBJECTIVE

The aim of this study was to characterize the association between percentage change in hemoglobin (ΔHb)—i.e., the difference between preoperative Hb and in-hospital nadir Hb concentration—and perioperative adverse events among spine surgery patients.

METHODS

Patients who underwent spine surgery at the authors’ institution between December 4, 2008, and June 26, 2015, were eligible for this retrospective study. Patients who underwent the following procedures were included: atlantoaxial fusion, subaxial anterior cervical fusion, subaxial posterior cervical fusion, anterior lumbar fusion, posterior lumbar fusion, lateral lumbar fusion, excision of intervertebral disc, and excision of spinal cord lesion. Data on intraoperative transfusion were obtained from an automated, prospectively collected, anesthesia data management system. Data on postoperative hospital transfusions were obtained through an Internet-based intelligence portal. Percentage ΔHb was defined as: ([preoperative Hb − nadir Hb]/preoperative Hb) × 100. Clinical outcomes included in-hospital morbidity and length of stay associated with percentage ΔHb.

RESULTS

A total of 3949 patients who underwent spine surgery were identified. Of these, 1204 patients (30.5%) received at least 1 unit of packed red blood cells. The median nadir Hb level was 10.6 g/dl (interquartile range 8.7–12.4 g/dl), yielding a mean percentage ΔHb of 23.6% (SD 15.4%). Perioperative complications occurred in 234 patients (5.9%) and were more common in patients with a larger percentage ΔHb (p = 0.017). Hospital-related infection, which occurred in 60 patients (1.5%), was also more common in patients with greater percentage ΔHb (p = 0.001).

CONCLUSIONS

Percentage ΔHb is independently associated with a higher risk of developing any perioperative complication and hospital-related infection. The authors’ results suggest that percentage ΔHb may be a useful measure for identifying patients at risk for adverse perioperative events.

Utility of the Modified Surgical Apgar Score in a Head and Neck Cancer Population

Objective The Surgical Apgar Score (SAS) is a validated postoperative complication prediction model. The purpose of this study was to investigate the utility of the SAS in a diverse head and neck cancer population and to compare it with a recently developed modified SAS (mSAS) that accounts for intraoperative transfusion. Study Design Case series with chart review. Setting Academic tertiary care medical center. Subjects and Methods This study comprised 713 patients undergoing surgery for head and neck cancer from April 2012 to March 2015. SAS values were calculated according to intraoperative data obtained from anesthesia records. The mSAS was computed by assigning an estimated blood loss score of zero for patients receiving intraoperative transfusions. Primary outcome was 30-day postoperative morbidity. Results Mean SAS and mSAS were 6.3 ± 1.5 and 6.2 ± 1.7, respectively. SAS and mSAS were significantly associated with 30-day postoperative morbidity, length of stay, operative time, American Society of Anesthesiologists status, race, and body mass index ( P < .05); however, no significant association was detected for age, sex, and smoking status. Multivariable analysis identified SAS and mSAS as independent predictors of postoperative morbidity, with the mSAS ( P = .03) being a more robust predictor than the SAS ( P = .15). Strong inverse relationships were demonstrated for the SAS and mSAS with length of stay and operative time ( P < .0001). Conclusion The SAS serves as a useful metric for risk stratification of patients with head and neck cancer. With the inclusion of intraoperative transfusion, the mSAS demonstrates superior utility in predicting those at risk for postoperative complications.

Current practices in perioperative blood management for patients undergoing liver resection: a survey of surgeons and anesthesiologists

BACKGROUND

Development of intraoperative techniques and blood management strategies in liver resection, and the multidisciplinary nature of perioperative transfusion decision making, creates an opportunity for practice variation. The aim of this study was to describe the current practices in perioperative blood management and explore differences between surgeons and anesthesiologists.

STUDY DESIGN AND METHODS

A Web-based survey was developed, piloted, and circulated to Canadian liver surgeons and anesthesiologists. The survey focused on management of preoperative anemia, blood conservation strategies, estimation of blood loss, and transfusion decision making in a multidisciplinary setting.

RESULTS

A total of 198 physicians received the survey, with 117 responding (59%). Most responding surgeons (67%) perform more than 20 liver resections per year, while most responding anesthesiologists (90%) take part in fewer than 20. Anesthesiologists most commonly stated that preoperative anemia is managed by someone else (38%), while surgeons most commonly reported "no specific treatment" (45%). The most common intraoperative blood conservation technique used is administration of antifibrinolytics (63% used them at least occasionally). The most important factor for anesthesiologists when deciding on an intraoperative transfusion was hemoglobin value (47%); for surgeons, it was patient hemodynamics (33%). Compared to when they started their career, 60% of respondents felt that they were less likely to transfuse a patient now.

CONCLUSION

The results of our survey provide insights into current transfusion practice and decision making in liver resection, including a comparison between anesthesiologist and surgeon transfusion behavior. Management of preoperative anemia, increased use of intraoperative blood conservation techniques, and improved communication between providers were identified as targets for quality improvement.

Effect of liberal blood transfusion on clinical outcomes and cost in spine surgery patients

BACKGROUND CONTEXT

Blood transfusions in spine surgery are shown to be associated with increased patient morbidity. The association between transfusion performed using a liberal hemoglobin (Hb) trigger-defined as an intraoperative Hb level of ≥10 g/dL, a postoperative level of ≥8 g/dL, or a whole hospital nadir between 8 and 10 g/dL-and perioperative morbidity and cost in spine surgery patients is unknown and thus was investigated in this study.

PURPOSE

This study aimed to describe the perioperative outcomes and economic cost associated with liberal Hb trigger transfusion among spine surgery patients.

STUDY DESIGN/SETTING

This is a retrospective study.

PATIENT SAMPLE

The surgical billing database at our institution was queried for inpatients discharged between 2008 and 2015 after the following procedures: atlantoaxial fusion, anterior cervical fusion, posterior cervical fusion, anterior lumbar fusion, posterior lumbar fusion, lateral lumbar fusion, other procedures, and tumor-related surgeries. In total, 6,931 patients were included for analysis.

OUTCOME MEASURES

The primary outcome was composite morbidity, which was composed of (1) infection (sepsis, surgical-site infection, Clostridium difficile infection, or drug-resistant infection); (2) thrombotic event (pulmonary embolus, deep venous thrombosis, or disseminated intravascular coagulation); (3) kidney injury; (4) respiratory event; and (5) ischemic event (transient ischemic attack, myocardial infarction, or cerebrovascular accident).

MATERIALS AND METHODS

Data on intraoperative transfusion were obtained from an automated, prospectively collected anesthesia data management system. Data on postoperative hospital transfusion were obtained through a Web-based intelligence portal. Based on previous research, we analyzed the data using three definitions of a liberal transfusion trigger in patients who underwent red blood cell transfusion: a liberal intraoperative Hb trigger as a nadir Hb level of 10 g/dL or greater, a liberal postoperative Hb trigger as a nadir Hb level of 8 g/dL or greater, or a whole hospital nadir Hb level of 8-10 g/dL. Variables analyzed included in-hospital morbidity, mortality, length of stay, and total costs associated with a liberal transfusion strategy.

RESULTS

Among patients with a whole hospital stay nadir Hb between 8 and 10 g/dL, transfused patients demonstrated a longer in-hospital stay (median [interquartile range], 6 [5-9] vs. 4 [3-6] days; p<.0001) and a higher perioperative morbidity (n=145 [11.5%] vs. n=74 [6.1%], p<.0001) than those not transfused. Even after adjusting for age, gender, race, American Society of Anesthesiologists class, Charlson Comorbidity Index score, estimated blood loss, baseline Hb value, and surgery type, logistic regression analysis revealed that patients with a nadir Hb of 8-10 g/dL who were transfused had an independently higher risk of perioperative morbidity (odds ratio=2.11, 95% confidence interval, 1.44-3.09; p<.0001). Estimated additional costs associated with liberal trigger use, defined as a transfusion occurring in patients with a whole hospital stay nadir Hb of 8-10 g/dL, ranged from $202,675 to $700,151 annually.

CONCLUSIONS

Transfusion using a liberal trigger is associated with increased morbidity, even after controlling for possible confounders. Our results suggest that modification of transfusion practice may be a potential area for improving patient outcomes and reducing costs.

Physiologic correlates of intraoperative blood transfusion among patients undergoing major gastrointestinal operations

BACKGROUND

Guidelines for transfusion focus on nadir levels of hemoglobin. Hemoglobin triggers may not be helpful, however, in defining appropriate intraoperative use of packed red blood cells. We sought to define the use of intraoperative packed red blood cells relative to quantitative physiologic factors at the time of operation.

METHODS

Prospective intraoperative data on patients undergoing a major gastrointestinal operation between 2010 and 2014 were analyzed. Risk of intraoperative transfusion was assessed with multivariable extended Cox models using baseline clinical covariates and time-varying intraoperative covariates.

RESULTS

Among 2,316 patients, the mean preoperative hemoglobin was 12.6 g/dL (standard deviation = 2.0 g/dL), while the median estimated blood loss was 200 mL (interquartile range: 100-55 mL). Overall, 357 (15.4%) patients received a transfusion intraoperatively. A greater hazard of transfusion was associated with a greater American Society of Anesthesiologists class (ref: American Society of Anesthesiologists class I-II; American Society of Anesthesiologists class III-IV; hazard ratio = 1.44, 95% confidence interval, 1.18-1.77, P < .001), and a lesser preoperative hemoglobin level (per 1 g/dL increase; hazard ratio = 0.70, 95% confidence interval, 0.65-0.74, P < .001). In addition, an increase in heart rate of 10 beats/min above the cumulative average at any measurement was associated with up to a 30% increased probability of transfusion (hazard ratio = 1.30, 95% confidence interval, 1.15-1.47, P < .001); similarly, an increase in mean arterial pressure of 10 mm Hg was associated with an 8% decreased likelihood of transfusion (hazard ratio = 0.92, 95% confidence interval, 87-0.99, P = .017). In contrast, nadir hemoglobin was not associated with the risk of receiving a transfusion (hazard ratio = 1.10, 95% confidence interval, 0.97-1.23, P = .129). Among patients who received an intraoperative transfusion, 9.2% (n = 33) never had a hemoglobin nadir below 10 g/dL, nor an average mean arterial pressure less than 65 mm Hg or a heart rate greater than 100 beats/min around the time of transfusion.

CONCLUSION

Among the intraoperative factors, heart rate, and mean arterial pressure were strongly associated with the likelihood of receiving a transfusion, despite the observation that 9.2% of patients never had a physiologic indicator for transfusion or a nadir hemoglobin below 10 g/dL, suggesting a subset of patients could benefit from a decrease in intraoperative rate of transfusion.

Impact of Delta Hemoglobin on Provider Transfusion Practices and Post-operative Morbidity Among Patients Undergoing Liver and Pancreatic Surgery

BACKGROUND

Delta hemoglobin (ΔHb) is defined as the difference between the preoperative Hb and the lowest post-operative Hb level. We sought to define the impact of ΔHb relative to nadir Hb levels on the likelihood of transfusion, as well as characterize the impact of ΔHb and nadir Hb on morbidity among a large cohort of patients undergoing complex hepatopancreatobiliary (HPB) surgery.

METHODS

Patients who underwent pancreatic or hepatic resection between January 1, 2009 and June 30, 2015 at Johns Hopkins Hospital were identified. Data on the perioperative ΔHb, nadir Hb, as well as blood utilization were obtained and analyzed. Multivariable logistic regression models were used to identify the factors associated with ΔHb and the impact of ΔHb on perioperative morbidity. A Bayesian model was used to evaluate the correlation of ΔHb and nadir Hb with the likelihood of transfusion, as well as the impact on morbidity.

RESULTS

A total of 4363 patients who underwent hepatobiliary (n = 2200, 50.4 %) or pancreatic (n = 2163, 49.6 %) surgery were identified. More than one quarter of patients received at least one unit of packed red blood cells (PRBC) (n = 1187, 27.2 %). The median nadir Hb was 9.2 (IQR 7.9-10.5) g/dL resulting in an average ΔHb of 3.4 mg/dL (IQR 2.2-4.7) corresponding to 26.3 %. Both ΔHb and nadir Hb strongly influenced provider behavior with regards to use of transfusion. Among patients with the same nadir Hb, ΔHb was strongly associated with use of transfusion; among patients who had a nadir Hb ≤6 g/dL, the use of transfusion was only 17.9 % when the ΔHb = 10 % versus 49.1 and 80.9 % when the ΔHb was 30 or 50 %, respectively. Perioperative complications occurred in 584 patients (13.4 %) and were more common among patients with a higher value of ΔHb, as well as patients who received PRBC (both P < 0.001).

CONCLUSIONS

The combination of the Hb trigger with ΔHb was associated with transfusion practices among providers. Larger ΔHb values, as well as receipt of transfusion, were strongly associated with risk of perioperative complication following HPB surgery.

Improvement of the Surgical Apgar Score by Addition of Intraoperative Blood Transfusion Among Patients Undergoing Major Gastrointestinal Surgery

BACKGROUND

The surgical Apgar score (SAS) has been shown to correlate with postoperative outcomes. A key component of the SAS is estimated blood loss (EBL), which has been shown to be inaccurate and discordant with intraoperative blood transfusion. Given this, the objective of the current study was to assess the added predictive value of the including receipt of intraoperative transfusion to the SAS.

METHODS

We identified 1833 patients undergoing major gastrointestinal surgery (pancreatic, hepato-biliary, and colorectal) between January 1, 2010 and August 31, 2013 at Johns Hopkins Hospital. The primary outcome was postoperative complications or death. A modified SAS was created by assigning a "0" EBL score for every patient who received an intraoperative blood transfusion, regardless of the actual EBL. Model performance was tested using logistic regression and c-statistic.

RESULTS

Mean EBL of the entire cohort was 250 mL. Two hundred ninety-two patients (15.9 %) received at least 1 unit of blood intraoperatively. Approximately, one half of patients (55.1 %) who had an EBL <1000 mL received an intraoperative transfusion. Patients who received an intraoperative transfusion (transfusion n = 94, 32.2 % vs. no transfusion n = 221, 14.3 %; P < 0.001) and those with increasing EBL had a higher incidence of postoperative morbidity and/or death (≤100 mL: 11.6 %, 101-600 mL: 16.9 %, 601-1000 mL: 24.5 %, >1000 mL: 29.2 %; P < 0.001). The variance inflation factor between EBL and intraoperative transfusion was 1.23 for postoperative morbidity/mortality, suggesting that the multicollinearity between the two variables was low. With the inclusion of intraoperative transfusion in the modified SAS, the modified model (c-statistic 0.6552) had an improved discrimination of predicting postoperative morbidity and mortality as compared to the original SAS (c-statistic 0.6391) (P = 0.01). The modified SAS demonstrated improvement in predicting raw differences in the incidence of postoperative morbidity/mortality based on the overall score (P < 0.05).

CONCLUSIONS

The inclusion of intraoperative transfusion in a modified SAS significantly improves the risk-stratifying ability of the score with regard to postoperative morbidity and mortality. Given the variability of intraoperative transfusion, its discordance with EBL, and its strong negative impact on postoperative outcomes, we strongly support the inclusion of this factor in a modified SAS.

Protocol for a national blood transfusion data warehouse from donor to recipient

INTRODUCTION

Blood transfusion has health-related, economical and safety implications. In order to optimise the transfusion chain, comprehensive research data are needed. The Dutch Transfusion Data warehouse (DTD) project aims to establish a data warehouse where data from donors and transfusion recipients are linked. This paper describes the design of the data warehouse, challenges and illustrative applications.

STUDY DESIGN AND METHODS

Quantitative data on blood donors (eg, age, blood group, antibodies) and products (type of product, processing, storage time) are obtained from the national blood bank. These are linked to data on the transfusion recipients (eg, transfusions administered, patient diagnosis, surgical procedures, laboratory parameters), which are extracted from hospital electronic health records.

APPLICATIONS

Expected scientific contributions are illustrated for 4 applications: determine risk factors, predict blood use, benchmark blood use and optimise process efficiency. For each application, examples of research questions are given and analyses planned.

CONCLUSIONS

The DTD project aims to build a national, continuously updated transfusion data warehouse. These data have a wide range of applications, on the donor/production side, recipient studies on blood usage and benchmarking and donor-recipient studies, which ultimately can contribute to the efficiency and safety of blood transfusion.

Understanding Perioperative Transfusion Practices in Gastrointestinal Surgery-a Practice Survey of General Surgeons

BACKGROUND

Despite guidelines recommending restrictive red blood cell transfusion (RBCT) strategies, perioperative transfusion practices still vary significantly. To understand the underlying mechanisms that lead to gaps in practice, we sought to assess the attitudes of surgeons regarding the perioperative management of anemia and use of RBCT in patients having gastrointestinal surgery.

METHODS

We conducted a self-administered Web-based survey of general surgery staff and residents, in a network of eight academic institutions at the University of Toronto. We developed a questionnaire using a systematic approach of items generation and reduction. We tested face and content validity and test-retest reliability. We administered the survey via emails, with planned reminders.

RESULTS

Total response rate was 48.1 % (62/125). Half (51.0 %) of respondents stated that they were unlikely to conduct a preoperative anemia work-up. About 54.0 % reported ordering preoperative oral iron supplementation for anemia. Most respondents indicated using a 70 g/L hemoglobin trigger (92.0 %) for transfusion. Factors increasing thresholds above 70 g/L included cardiac comorbidity (58.0 %), acute cardiac disease (94.0 %), symptomatic anemia (68.0 %), and suspected bleeding (58.0 %). With those factors, the transfusion threshold often increased above 90 g/L. Respondents perceived RBCTs to increase the postoperative morbidity (62 %), but not to impact the mortality (48 %) and cancer recurrence (52 %). Institutional protocols (68.0 %), blood conservation clinics (44.0 %), and clinical practice guidelines (84.0 %) were believed to encourage restrictive use of RBCTs.

CONCLUSION

Self-reported perioperative transfusion practices for GI surgery are heterogeneous. Few respondents investigated preoperative anemia. Stated use of RBCT indications varied from recommendations in published guidelines for patients with symptomatic anemia. Establishing team consensus and implementing local blood management guidelines appear necessary to improve uptake of evidence-based recommendations.

Nomogram to predict perioperative blood transfusion for hepatopancreaticobiliary and colorectal surgery

Background

Predictive tools assessing risk of transfusion have not been evaluated extensively among patients undergoing complex gastrointestinal surgery. In this study preoperative variables associated with blood transfusion were incorporated into a nomogram to predict transfusion following hepatopancreaticobiliary (HPB) or colorectal surgery.

Methods

A nomogram to predict receipt of perioperative transfusion was developed using a cohort of patients who underwent HPB or colorectal surgery between January 2009 and December 2014. The discriminatory ability of the nomogram was tested using the area under the receiver operating characteristic (ROC) curve and internal validation performed via bootstrap resampling.

Results

Among 4961 patients undergoing either a HPB (56·3 per cent) or colorectal (43·7 per cent) resection, a total of 1549 received at least 1 unit of packed red blood cells, giving a perioperative transfusion rate of 31·2 per cent. On multivariable analysis, age 65 years and over (odds ratio (OR) 1·52), race (versus white: black, OR 1·58; Asian, OR 1·86), preoperative haemoglobin 8·0 g/dl or less (versus over 12·0 g/dl: OR 26·79), preoperative international normalized ratio more than 1·2 (OR 2·44), Charlson co-morbidity index score over 3 (OR 1·86) and procedure type (versus colonic surgery: major hepatectomy, OR 1·71; other pancreatectomy, OR 2·12; rectal surgery, OR 1·39; duodenopancreatectomy, OR 2·65) were associated with a significantly higher risk of transfusion and were included in the nomogram. A nomogram was constructed to predict transfusion using these seven variables. Discrimination and calibration of the nomogram revealed good predictive abilities (area under ROC curve 0·756).

Conclusion

The nomogram predicted blood transfusion in major HPB and colorectal surgery.

Efficacy and Safety of Stroke Volume Variation-Guided Fluid Therapy for Reducing Blood Loss and Transfusion Requirements During Radical Cystectomy: A Randomized Clinical Trial

Radical cystectomy, which is performed to treat muscle-invasive bladder tumors, is among the most difficult urological surgical procedures and puts patients at risk of intraoperative blood loss and transfusion. Fluid management via stroke volume variation (SVV) is associated with reduced intraoperative blood loss. Therefore, we evaluated the efficacy and safety of SVV-guided fluid therapy for reducing blood loss and transfusion requirements in patients undergoing radical cystectomy.This study included 48 patients who underwent radical cystectomy, and these patients were randomly allocated to the control group and maintained at <10% SVV (n = 24) or allocated to the trial group and maintained at 10% to 20% SVV (n = 24). The primary endpoints were comparisons of the amounts of intraoperative blood loss and transfused red blood cells (RBCs) between the control and trial groups during radical cystectomy. Intraoperative blood loss was evaluated through the estimated blood loss and estimated red cell mass loss. The secondary endpoints were comparisons of the postoperative outcomes between groups.A total of 46 patients were included in the final analysis: 23 patients in the control group and 23 patients in the trial group. The SVV values in the trial group were significantly higher than in the control group. Estimated blood loss, estimated red cell mass loss, and RBC transfusion requirements in the trial group were significantly lower than in the control group (734.3 ± 321.5 mL vs 1096.5 ± 623.9 mL, P = 0.019; 274.1 ± 207.8 mL vs 553.1 ± 298.7 mL, P <0.001; 0.5 ± 0.8 units vs 1.9 ± 2.2 units, P = 0.005). There were no significant differences in postoperative outcomes between the two groups.SVV-guided fluid therapy (SVV maintained at 10%-20%) can reduce blood loss and transfusion requirements in patients undergoing radical cystectomy without resulting in adverse outcomes. These findings provide useful information for optimal fluid management during radical cystectomy.

Large Variation in Blood Transfusion Use After Colorectal Resection: A Call to Action

BACKGROUND

Perioperative blood transfusions are associated with an increased risk of adverse postoperative outcomes through immunomodulatory effects.

OBJECTIVE

The purpose of this study was to identify factors associated with variation in blood transfusion use after elective colorectal resection and associated postoperative infectious complications

DESIGN

This was a retrospective cohort study.

SETTINGS

The study included elective colorectal resections in New York State from 2001 to 2013.

PATIENTS

The study cohort consists of 125,160 colorectal resections. Patients who were admitted nonelectively or who were admitted before the date of surgery were excluded.

MAIN OUTCOME MEASURES

Receipt of a perioperative allogeneic red blood cell transfusion and the secondary end points of postoperative pneumonia, surgical site infection, intra-abdominal abscess, and sepsis were measured.

RESULTS

The overall rate of perioperative blood transfusion for the study cohort was 13.9%. The unadjusted blood transfusion rates ranged from 2.4% to 58.7% for individual surgeons and 2.9% to 32.8% for individual hospitals. After controlling for patient-, surgeon-, and hospital-level factors in a 3-level mixed-effects multivariable model, significant variation was still present across both surgeons (p < 0.0001) and hospitals (p < 0.0001), with a 16.8-fold difference in adjusted blood transfusion rates across surgeons and a 13.2-fold difference in adjusted blood transfusion rates across hospitals. Receipt of a blood transfusion was also independently associated with pneumonia (OR = 3.23 (95% CI, 2.92-3.57)), surgical site infection (OR = 2.27 (95% CI, 2.14-2.40)), intra-abdominal abscess (OR = 2.72 (95% CI, 2.41-3.07)), and sepsis (OR = 4.51 (95% CI, 4.11-4.94)).

LIMITATIONS

Limitations include the retrospective design and the possibility of miscoding within administrative data.

CONCLUSIONS

Large surgeon- and hospital-level variations in perioperative blood transfusion use for patients undergoing colorectal resection are present despite controlling for patient-, surgeon-, and hospital-level factors. In addition, receipt of a blood transfusion was independently associated with an increased risk of postoperative infectious complications. These findings support the creation and implementation of perioperative blood transfusion protocols aimed at limiting unwarranted variation.

Hemostasis and Hepatic Surgery

Operative blood loss is a major source of morbidity and even mortality for patients undergoing hepatic resection. This review discusses strategies to minimize blood loss and the utilization of allogeneic blood transfusion pertaining to oncologic hepatic surgery.

Relationship between Stroke Volume Variation and Blood Transfusion during Liver Transplantation

BACKGROUND

Intraoperative blood transfusion increases the risk for perioperative mortality and morbidity in liver transplant recipients. A high stroke volume variation (SVV) method has been proposed to reduce blood loss during living donor hepatectomy. Herein, we investigated whether maintaining high SVV could reduce the need for blood transfusion and also evaluated the effect of the high SVV method on postoperative outcomes in liver transplant recipients.

METHODS

We retrospectively analyzed 332 patients who underwent liver transplantation, divided into control (maintaining <10% of SVV during surgery) and high SVV (maintaining 10-20% of SVV during surgery) groups. We evaluated the blood transfusion requirement and hemodynamic parameters, including SVV, as well as postoperative outcomes, such as incidences of acute kidney injury, durations of postoperative intensive care unit and hospital stay, and rates of 1-year mortality.

RESULTS

Mean SVV values were 7.0% ± 1.3% in the control group (n = 288) and 11.2% ± 1.8% in the high SVV group (n = 44). The median numbers of transfused packed red blood cells and fresh frozen plasmas in the high SVV group were significantly lower than those in control group (0 vs. 2 units, P = 0.003; and 0 vs. 3 units, P = 0.033, respectively). No significant between-group differences were observed for postoperative outcomes.

CONCLUSIONS

Maintaining high SVV can reduce the blood transfusion requirement during liver transplantation without worsening postoperative outcomes. These findings provide insights into improving perioperative management in liver transplant recipients.