Efficacy of intraoperative cell salvage in decreasing perioperative blood transfusion rates in first-time cardiac surgery patients: a retrospective study.

BACKGROUND: Evidence regarding the safety and efficacy of intraoperative cell salvage (ICS) in transfusion reduction during cardiac surgery remains conflicting. We sought to evaluate the impact of routine ICS on outcomes following cardiac surgery. METHODS: We conducted a retrospective analysis of patients who underwent nonemergent, first-time cardiac surgery 18 months before and 18 months after the implementation of routine ICS. Perioperative transfusion rates, postoperative bleeding, clinical and hematological outcomes, and overall cost were examined. We used multivariable logistic regression modelling to determine the risk-adjusted effect of ICS on likelihood of perioperative transfusion. RESULTS: A total of 389 patients formed the final study population (186 undergoing ICS and 203 controls). Patients undergoing ICS had significantly lower perioperative transfusion rates of packed red blood cells (pRBCs; 33.9% v. 45.3% p = 0.021), coagulation products (16.7% v. 32.5% p < 0.001) and any blood product (38.2% v. 52.7%, p = 0.004). Patients receiving ICS had decreased mediastinal drainage at 12 h (mean 320 [range 230-550] mL v. mean 400 [range 260-690] mL, p = 0.011) and increased postoperative hemoglobin (mean 104.7 ± 13.2 g/L v. 95.0 ± 11.9 g/L, p < 0.001). Following adjustment for other baseline and intraoperative covariates, ICS emerged as an independent predictor of lower perioperative transfusion rates of pRBCs (odds ratio [OR] 0.52, 95% confidence interval [CI] 0.31-0.87), coagulation products (OR 0.41, 95% CI 0.24-0.71) and any blood product (OR 0.47, 95% CI 0.29-0.77). Additionally, ICS was associated with a cost benefit of $116 per patient. CONCLUSION: Intraoperative cell salvage could represent a clinically cost-effective way of reducing transfusion rates in patients undergoing cardiac surgery. Further research on systematic ICS is required before recommending it for routine use.

CONTEXTE: Les résultats d'études portant sur l'innocuité et l'efficacité de l'autotransfusion peropératoire (ATPO) comme mesure de réduction du besoin de transfusion durant une chirurgie cardiaque sont contradictoires. Nous avons cherché à évaluer l'incidence du recours systématique à l'ATPO sur les issues de chirurgies cardiaques. MÉTHODES: Nous avons mené une analyse rétrospective portant sur des patients ayant subi une première chirurgie cardiaque non urgente 18 mois avant et 18 mois après l'introduction de l'ATPO systématique. Les taux de transfusion périopératoire et d'hémorragie postopératoire, les résultats cliniques et hématologiques et le coût total ont été analysés. Nous avons utilisé un modèle de régression logistique multivariée pour déterminer l'incidence ajustée en fonction du risque du recours à l'ATPO sur la probabilité qu'une transfusion périopératoire soit nécessaire. RÉSULTATS: L'échantillon à l'étude était composé de 389 patients (186 dans le groupe ATPO et 203 dans le groupe témoin). Par rapport au groupe témoin, les patients ayant reçu une ATPO ont eu besoin significativement moins souvent d'une transfusion de concentrés de globules rouges (33,9 % c. 45,3 %; p = 0,021), de produits coagulants (16,7 % c. 32,5 %; p < 0,001) et de produits sanguins, tous types confondus (38,2 % c. 52,7 %; p = 0,004). Chez les patients ayant reçu une ATPO, on a constaté un volume de drainage médiastinal après 12 h plus faible (moyenne : 320 mL [étendue de 230-550] c. 400 mL [étendue de 260-690]; p = 0,011) et une hémoglobine postopératoire plus élevée (moyenne : 104,7 ± 13,2 g/L c. 95,0 ± 11,9 g/L; p < 0,001). Après des ajustements pour tenir compte d'autres covariables des mesures de base et peropératoires, nous avons conclu que le recours à l'ATPO était un facteur prédicteur indépendant de taux de transfusion périopératoire plus faibles de concentré de globules rouges (rapport de cotes [RC] : 0,52; intervalle de confiance [IC] à 95 % : 0,31-0,87), de produits coagulants (RC : 0,41; IC à 95 % : 0,24-0,71) et de produits sanguins, tous types confondus (RC : 0,47; IC à 95 % : 0,29-0,77). De plus, l'ATPO a été associée à des économies de 116 $ par patient. CONCLUSION: L'autotransfusion peropératoire pourrait constituer un moyen cliniquement efficace en fonction des coûts de réduire les taux de transfusion des patients subissant une chirurgie cardiaque. D'autres recherches sur le recours systématique à l'ATPO devront être menées avant qu'on puisse recommander son utilisation de routine.

Impact of Obesity on Intensive Care Unit Resource Utilization After Cardiac Operations.

BACKGROUND: Much has been published about the effect of obesity on adverse outcomes after cardiac operations, yet little is known regarding the effect of obesity on intensive care unit (ICU) resource utilization. This study examined the effect of obesity on ICU resource utilization after cardiac operations. METHODS: All patients with a body mass index (BMI) of 18.5 kg/m2 or higher who underwent a cardiac surgical procedure between 2006 and 2013 were stratified into the following weight categories: normal (BMI 18.5 to 24.99 kg/m2), preobese (BMI 25 to 29.99 kg/m2), obese class I (BMI 30 to 34.99 kg/m2), obese class II (BMI 35 to 39.99 kg/m2), and obese class III (BMI ≥40 kg/m2). Comparisons between weight categories were done, and the risk-adjusted effect of weight category on prolonged ICU stay, prolonged ventilation, and ICU readmission was determined. RESULTS: Of the 5,365 included patients, 1,948 were obese. Patients with greater obesity experienced longer ICU time, longer ventilation time, and increased ICU readmission. After adjustment, increasing obesity remained independently associated with greater likelihood of prolonged ICU stay (obese class II: odds ratio [OR], 2.4; 95% confidence interval [CI], 1.55 to 3.61; obese class III: OR, 4.1; 95% CI, 2.38 to 7.05), prolonged ventilation (obese class III: OR, 3.4; 95% CI, 1.57 to 7.22), and ICU readmission (obese class II: OR, 3.0; 95% CI, 1.70 to 5.31; obese class III: OR, 2.9; 95% CI, 1.32 to 6.36). CONCLUSIONS: Increasing obesity was associated with a significant increase in ICU resource utilization after cardiac operations. Further study is needed to determine the mechanisms underlying this association and how the adverse effects of obesity may be mitigated.

Outcomes in octogenarians undergoing coronary artery bypass grafting.

BACKGROUND: Although octogenarians are being referred for coronary artery bypass grafting (CABG) with increasing frequency, contemporary outcomes have not been well described. We examined data from 4 Canadian centres to determine outcomes of CABG in this age group. METHODS: Data for the years 1996 to 2001 were examined in a comparison of octogenarians with patients less than 80 years of age. Logistic regression analysis was used to adjust for preoperative factors and to generate adjusted rates of mortality and postoperative stroke. RESULTS: A total of 15,070 consecutive patients underwent isolated CABG during the study period. Overall, 725 (4.8%) were 80 years of age or older, the proportion increasing from 3.8% in 1996 to 6.2% in 2001 (p for linear trend = 0.03). The crude rate of death was higher among the octogenarians (9.2% v. 3.8%; p < 0.001), as was the rate of stroke (4.7% v. 1.6%, p < 0.001). The octogenarians had a significantly greater burden of comorbid conditions and more urgent presentation at surgery. After adjustment, the octogenarians remained at greater risk for in-hospital death (odds ratio [OR] 2.64, 95% confidence interval [CI] 1.95-3.57) and stroke (OR 3.25, 95% CI 2.15-4.93). Mortality declined over time for both age groups (p for linear trend < 0.001 for both groups), but the incidence of postoperative stroke did not change (p for linear trend = 0.61 [age < 80 years] and 0.08 [age > or = 80 years]). Octogenarians who underwent elective surgery had crude and adjusted rates of death (OR 1.31, 95% CI 0.60-2.90) and stroke (OR 1.59, 95% CI 0.57-4.44) that were higher than but not significantly different from those for non-octogenarians who underwent elective surgery. INTERPRETATION: In this study, rates of death and stroke were higher among octogenarians, although the adjusted differences in mortality over time were decreasing. The rate of adverse outcomes in association with elective surgery was similar for older and younger patients.

Variation in transfusion rates within a single institution: exploring the effect of differing practice patterns on the likelihood of blood product transfusion in patients undergoing cardiac surgery.

OBJECTIVES: Rates of perioperative transfusion vary widely among patients undergoing cardiac surgery. Few studies have examined factors beyond the clinical characteristics of the patients that may be responsible for such variation. The purpose of this study was to determine whether differing practice patterns had an impact on variation in perioperative transfusion at a single center. METHODS: Patients who underwent cardiac surgery at a single center between 2004 and 2011 were considered. Comparisons were made between patients who had received a perioperative transfusion and those who had not from the clinical factors at baseline, intraoperative variables, and differing practice patterns, as defined by the surgeon, anesthesiologist, perfusionist, and the year in which the procedure was performed. The risk-adjusted effect of these factors on perioperative transfusion rates was determined using multivariable regression modeling techniques. RESULTS: The study population comprised 4823 patients, of whom 1929 (40.0%) received a perioperative transfusion. Significant variation in perioperative transfusion rates was noted between surgeons (from 32.4% to 51.5%, P < .0001), anesthesiologists (from 34.4% to 51.9%, P < .0001) and across year (from 28.2% in 2004 to 48.8% in 2008, P < .0001). After adjustment for baseline and intraoperative variables, surgeon, anesthesiologist, and year of procedure were each found to be independent predictors of perioperative transfusion. CONCLUSIONS: Differing practice patterns contribute to significant variation in rates of perioperative transfusion within a single center. Strategies aimed at reducing overall transfusion rates must take into account such variability in practice patterns and account for nonclinical factors as well as known clinical predictors of blood transfusions.

Increased Distance From the Tertiary Cardiac Center Is Associated With Worse 30-Day Outcomes After Cardiac Operations.

BACKGROUND: Numerous studies have examined the effect of geographic place of residence on access to cardiovascular care, but few have examined their effect on outcomes after cardiac operations. This study examined the effect of geographic place of residence on in-hospital and 30-day outcomes after cardiac operations. METHODS: We performed a retrospective analysis of all patients undergoing nonemergency cardiac operations at a single institution between April 2004 and March 2011. Geographic place of residence was defined as the driving distance from the patient's home to the tertiary cardiac care center divided into the following categories: 0 to 50 km, 50 to 100 km, 100 to 150 km, 150 to 200 km, 200 to 250 km, and more than 250 km. Multivariable logistic regression was used to determine the independent effect of driving distance on in-hospital and 30-day outcomes. RESULTS: The final study population included 4,493 patients, of whom 3,897 (86.7%) had 30-day follow-up. After adjusting for differences among patient groups, no consistent relationship existed between distance and in-hospital outcomes. However, increased distance beyond 100 km was significantly associated with a greater risk of adverse outcomes at 30 days (0 to 50 km: referent; 50 to 100 km: odds ratio, 1.16 [95% confidence interval, 0.83 to 1.62]; 100 to 150 km: 1.32 [1.05 to 1.65], 150 to 200 km: 1.68 [1.33 to 2.11], 200 to 250 km: 1.41 [1.06 to 1.88], and >250 km: 1.30 [1.04 to 1.63]). CONCLUSIONS: Patients who live at an increased distance from the tertiary cardiac care center are more likely to have worse 30-day outcomes after cardiac operations. Further study is required to determine the mechanisms underlying this relationship and how such inequalities may be minimized.