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Background: Restrictive red cell transfusion is preferable to liberal transfusion in most clinical situations. However, intraoperative transfusion decisions are challenging due to uncertainty about the amount and rate of bleeding, the poor correlation of hemoglobin levels with blood loss and the effects of anesthetics on blood volume and physiologic responses. Clinicians frequently use hemoglobin levels to guide transfusion. While these "triggers" assume that the patient is normovolemic, they are often applied in situations confounded by hemodilution or hemoconcentration. We postulated that accurate measurement of surgical blood loss would facilitate prediction of postoperative hemoglobin levels, potentially leading to more accurate intraoperative transfusion decisions.

Introduction Following bariatric surgery, ongoing postoperative testing is required to measure nutritional deficiencies; the purpose of this study was to quantify the prevalence of these nutritional deficiencies based on two-year follow-up tests at recommended time points. Methods and procedures A retrospective data analysis was conducted of all laboratory tests for bariatric patients who underwent surgery between May 2016 and January 2018 with available lab data (n = 397). Results for nine different nutritional labs were categorized into six recommended postoperative time periods based on time elapsed since the procedure date. Binary variables were created for each laboratory result to calculate descriptive statistics of abnormalities for each lab test over time and used in the individual GEE logistic regression models. Grouped logistic regression examined the total nutritional deficiencies of the nine combined nutrients considering total available labs. Results Multiple lab tests indicated a very low frequency of abnormalities (e.g., Vitamin A, Vitamin B12, Copper, and Folate). Many of the nine included nutritional labs had an average deficiency of less than 10% across all time points. The grouped logistic model found preoperative nutritional deficiency to be predictive of postoperative nutritional deficiency (OR 3.70, p < 0.001). Conclusions We found the vast majority of routine lab test results to be normal at multiple time points. Current practice can add up to significant lab expenses over time. The frequency of postoperative testing in this population may be redundant and of very little value. Unnecessary follow-up laboratory testing costs the patients and the health care system in both time and resources. Patients with preoperative deficiencies appear to be at higher risk for nutritional deficiencies when compared to bariatric surgery patients that did not have preoperative nutritional deficiencies. Future research should focus on defining cost effective postoperative lab testing guidelines for at risk bariatric patients.

Objective: To determine if accurate measurement of surgical blood loss using a novel device that photographs surgical sponges and calculates their hemoglobin content affects transfusion practice. Methods:We retrospectively compared transfusion events for patients having wound excisions using visual estimation of blood loss (traditional group; n=178) to similar events following device implementation (study group; n=221). Results:The study group (age 43 ± 22 years, body surface area burn 11.2 ± 18.0%, excision area 624, IQR 757 cm 2 , preoperative hemoglobin 10.7 ± 2.4 g/dl) did not differ significantly from the traditional group (age 42 ± 23 years (p=0.527), body surface area burn 12.2 ± 22.6% (p=0.661), excision area 753, IQR 505 cm 2 (p=0.485), and preoperative hemoglobin 10.7 ± 2.2 g/dl (p=0.833).Postoperative transfusion rates were significantly lower in the study group (6.3% vs. 12.9%; p=0.024), as was the proportion of transfused patients undergoing multiple transfusion events (13.0% vs. 34.9%; p=0.01). Red cell dose (units/transfused patient) was less in the study group compared to the traditional group (1.83 ± 1.09 vs. 2.51 ± 1.61 units; p=0.021).In a subgroup of patients requiring excision of burned areas ≥ 1,000 cm 2 (traditional group n=36, study group n=43), these differences were more significant. The postoperative transfusion rate fell from 44.4% to 14.0% (p=0.003), as did the percent of transfused patients experiencing multiple transfusion events (50.0% vs. 14.3%; p=0.004).Conclusions: Accurate measurement of surgical blood loss was associated with a decrease in transfusions suggesting more timely decision making. Informed transfusion decisions may result in fewer transfusions by avoiding over-transfusion related to both excessive hemodilution and inaccurate visual estimates.