The Association between Serum Albumin and Post-Operative Outcomes among Patients Undergoing Common Surgical Procedures: An Analysis of a Multi-Specialty Surgical Cohort from the National Surgical Quality Improvement Program (NSQIP)

Abstract

While studies have demonstrated an association between preoperative hypoalbuminemia and adverse clinical outcomes, the optimal serum albumin threshold for risk-stratification in the broader surgical population remains poorly defined. We sought define the optimal threshold of preoperative serum albumin concentration for risk-stratification of adverse post-operative outcomes. Using the American College of Surgeons National Surgical Quality Improvement Program Database, we identified 842,672 patients that had undergone a common surgical procedure in one of eight surgical specialties. An optimal serum albumin concentration threshold for risk-stratification was determined using receiver-operating characteristic analysis. Multivariable logistic regression analysis was used to evaluate the odds of adverse surgical events; a priori defined subgroup analyses were performed. A serum albumin threshold of 3.4 g/dL optimally predicted adverse surgical outcomes in the broader cohort. After multivariable analysis, patients with hypoalbuminemia had increased odds of death within 30 days of surgery (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.94–2.08). Hypoalbuminemia was associated with greater odds of primary adverse events among patients with disseminated cancer (OR 2.03, 95% CI 1.88–2.20) compared to patients without disseminated cancer (OR 1.47, 95% CI 1.44–1.51). The standard clinical threshold for hypoalbuminemia is the optimal threshold for preoperative risk assessment.

Using preoperative control nutritional status scores as prognostic factors for endometrial cancer

“…SA is an important factor used to evaluate patient nutritional status. Hypoalbuminemia indicates nutritional decline in patients with severe disease, and also malnutrition in cancer patients, and is reportedly associated with poor prognoses, increased staging, and reduced OS rates due to malignant tumors ( 25 – 28 ). Preoperative hypoproteinemia patients have also been shown to have increased tumor spread rates and increased risks from adverse outcomes within 1 month after surgery ( 25 ).…”

“…Hypoalbuminemia indicates nutritional decline in patients with severe disease, and also malnutrition in cancer patients, and is reportedly associated with poor prognoses, increased staging, and reduced OS rates due to malignant tumors ( 25 – 28 ). Preoperative hypoproteinemia patients have also been shown to have increased tumor spread rates and increased risks from adverse outcomes within 1 month after surgery ( 25 ). SA levels before treatment are independent prognostic parameters for disease-free and progression-free survival in EC patients ( 29 ).…”

Acid–Base Analysis in the Operating Room: A Bedside Stewart Approach

“…Ideally plasma albumin should be measured before major surgery and for high-risk patients, and repeated after large volumes of intravenous fluids or blood products (examples 1 and 3 in Boxes 1 and 3). For anesthesiologists, knowing preoperative plasma albumin concentration has added value in assessing patient risk due to the strong association between hypoalbuminemia (less than 35 g/l) and postoperative complications and mortality 35,36 due to both malnutrition and chronic disease.…”

Hypoalbuminemic malnutrition

“…14 Hypoalbuminemia is clearly and closely linked to poor outcomes [15][16][17] particularly in surgical patients. [17][18][19] In the early landmark Veterans' Affairs trial of preoperative feeding of surgical patients before abdominal surgery it was found that only in the severely malnourished patients diagnosed by weight loss and serum albumin levels did benefit in terms of noninfectious outcomes occur 20 from what would now be considered excessive parenteral nutrition therapy. The risks for surgery in hypoalbuminemic patients are substantial extending even to those undergoing metabolic surgery for obesity.…”

“…In patients who were critically ill with serum albumin levels <2.5 g/dl, some patients did not respond to nutrition support, which was linked to poorer intake of dietary protein, and they had a higher mortality 14 . Hypoalbuminemia is clearly and closely linked to poor outcomes 15‐17 particularly in surgical patients 17‐19 . In the early landmark Veterans’ Affairs trial of preoperative feeding of surgical patients before abdominal surgery it was found that only in the severely malnourished patients diagnosed by weight loss and serum albumin levels did benefit in terms of noninfectious outcomes occur 20 from what would now be considered excessive parenteral nutrition therapy.…”