Abstract
Nutritional status has become increasingly important in optimizing surgical outcomes
and preventing postoperative infection and wound complications. However, currently,
there is a paucity in the orthopaedics literature investigating the relationship between
nutritional status and wound complications following total knee arthroplasty (TKA).
Therefore, the purpose of this study was to determine the prevalence of (1) postoperative
infections, (2) wound complications, (3) concomitant infection with wound (CoIW) complication,
and (4) infection followed by wound complication by using (1) albumin, (2) prealbumin,
and (3) transferrin levels as indicators of nutritional status. These four different
outcome measures were chosen as they are encountered commonly in daily clinical practice.
A retrospective review of a national private payer database for patients who underwent
TKA with postoperative infections and wound complications stratified by preoperative
serum albumin (normal: 3.5–5 g/dL), prealbumin (normal: 16–35 mg/dL), and transferrin
levels (normal: 200–360 mg/dL) between 2007 and 2015 was conducted. Patients were
identified by Current Procedural Terminology (CPT), International Classification of
Disease, ninth revision (ICD-9) codes, and Logical Observation Identifiers Names and
Codes (LOINC). Linear regression was performed to evaluate changes over times. Yearly
rates of infection, as well as a correlation and odds ratio analysis of nutritional
laboratory values to postoperative complications, were also performed. Our query returned
a total of 161,625 TKAs, of which 11,047 (7%) had postoperative wound complications,
18,403 (11%) had infections, 6,296 (34%) had CoIW, and 4,877 (4%) patients with infection
developed wound complications. Albumin was the most commonly ordered laboratory test
when assessing complications (96%). Wound complications, infections, CoIW, and infection
with wound complications after were higher in those below the normal range: albumin
<3.5 g/dL (9, 14, 6, and 5%), prealbumin <15 mg/dL (20, 23, 13, and 12%), and transferrin
<200 mg/dL (12, 17, 6, and 6%). Preoperative albumin, prealbumin, and transferrin
values falling below the normal range represented an increased risk for postoperative
complications. Those patients who were in the normal range, however, did not have
an increased risk. Therefore, our results suggest that preoperative nutritional optimization
can play an important role in reducing the risk for postoperative complications.
Keywords
total knee arthroplasty - joint replacement - wound complications - albumin - prealbumin
- transferrin - malnutrition - infection
