Attributable harm of severe bleeding after cardiac surgery in hemodynamically stable patients.

BACKGROUND: We sought to quantify the effect of severe postoperative bleeding in hemodynamically stable patients following cardiac surgery. METHODS: We reviewed the charts of all cardiac surgery patients operated on at our institution between 2010 and 2014. After excluding patients with tamponade or MAP <60, we propensity matched patients having chest tube output >300 mL in the first postoperative hour, >200 mL in the second, and >100 mL in the third ("bleeding" group) with patients having <50 mL/h of chest tube output ("dry" group). The primary outcome was a composite of morbidity or mortality (excluding reexploration). RESULTS: 5016 patients were operated on between 2010 and 2014; of these, we included the records of 84 bleeding and 498 dry patients. Propensity matching resulted in 68 pairs of patients well-matched on baseline and operative variables. As compared to matched dry patients, bleeding patients were more likely to experience the primary outcome of any morbidity/mortality (36.8 vs. 13.2 %, p = 0.002), as well as ventilation >24 h (33.8 vs. 7.4 %, p < 0.001) and 30-day mortality (11.8 vs. 1.5 %, p = 0.02). Of the 84 bleeding patients, 46 underwent reexploration for bleeding within 24 h of surgery. A subgroup analysis propensity matching bleeding patients who were or were not reexplored <24 h demonstrated similarly poor outcomes in each group (primary outcome, 44.7 % reexplored vs. 50.0 % non-reexplored, p = 0.65), though reexplored patients were far less likely to require hematoma evacuation/washout >24 h after surgery (0 vs. 18.4 %, p = 0.005). CONCLUSIONS: Even among hemodynamically stable patients, severe bleeding is associated with markedly worse outcomes following cardiac surgery.

A pilot goal-directed perfusion initiative is associated with less acute kidney injury after cardiac surgery.

BACKGROUND: We sought to determine whether a pilot goal-directed perfusion initiative could reduce the incidence of acute kidney injury after cardiac surgery. METHODS: On the basis of the available literature, we identified goals to achieve during cardiopulmonary bypass (including maintenance of oxygen delivery >300 mL O2/min/m2 and reduction in vasopressor use) that were combined into a goal-directed perfusion initiative and implemented as a quality improvement measure in patients undergoing cardiac surgery at Johns Hopkins during 2015. Goal-directed perfusion initiative patients were matched to controls who underwent cardiac surgery between 2010 and 2015 using propensity scoring across 15 variables. The primary and secondary outcomes were the incidence of acute kidney injury and the mean increase in serum creatinine within the first 72 hours after cardiac surgery. RESULTS: We used the goal-directed perfusion initiative in 88 patients and matched these to 88 control patients who were similar across all variables, including mean age (61 years in controls vs 64 years in goal-directed perfusion initiative patients, P = .12) and preoperative glomerular filtration rate (90 vs 83 mL/min, P = .34). Controls received more phenylephrine on cardiopulmonary bypass (mean 2.1 vs 1.4 mg, P < .001) and had lower nadir oxygen delivery (mean 241 vs 301 mL O2/min/m2, P < .001). Acute kidney injury incidence was 23.9% in controls and 9.1% in goal-directed perfusion initiative patients (P = .008); incidences of acute kidney injury stage 1, 2, and 3 were 19.3%, 3.4%, and 1.1% in controls, and 5.7%, 3.4%, and 0% in goal-directed perfusion initiative patients, respectively. Control patients exhibited a larger median percent increase in creatinine from baseline (27% vs 10%, P < .001). CONCLUSIONS: The goal-directed perfusion initiative was associated with reduced acute kidney injury incidence after cardiac surgery in this pilot study.

Variation in Red Blood Cell Transfusion Practices During Cardiac Operations Among Centers in Maryland: Results From a State Quality-Improvement Collaborative.

BACKGROUND: Variation in red blood cell (RBC) transfusion practices exists at cardiac surgery centers across the nation. We tested the hypothesis that significant variation in RBC transfusion practices between centers in our state's cardiac surgery quality collaborative remains even after risk adjustment. METHODS: Using a multiinstitutional statewide database created by the Maryland Cardiac Surgery Quality Initiative (MCSQI), we included patient-level data from 8,141 patients undergoing isolated coronary artery bypass (CAB) or aortic valve replacement at 1 of 10 centers. Risk-adjusted multivariable logistic regression models were constructed to predict the need for any intraoperative RBC transfusion, as well as for any postoperative RBC transfusion, with anonymized center number included as a factor variable. RESULTS: Unadjusted intraoperative RBC transfusion probabilities at the 10 centers ranged from 13% to 60%; postoperative RBC transfusion probabilities ranged from 16% to 41%. After risk adjustment with demographic, comorbidity, and operative data, significant intercenter variability was documented (intraoperative probability range, 4% -59%; postoperative probability range, 13%-39%). When stratifying patients by preoperative hematocrit quartiles, significant variability in intraoperative transfusion probability was seen among all quartiles (lowest quartile: mean hematocrit value, 30.5% ± 4.1%, probability range, 17%-89%; highest quartile: mean hematocrit value, 44.8% ± 2.5%; probability range, 1%-35%). CONCLUSIONS: Significant variation in intercenter RBC transfusion practices exists for both intraoperative and postoperative transfusions, even after risk adjustment, among our state's centers. Variability in intraoperative RBC transfusion persisted across quartiles of preoperative hematocrit values.