Acute kidney injury in the context of staged revision arthroplasty and the use of antibiotic-laden cement spacers: a systematic review.

BACKGROUND: The most common cause of revision arthroplasty is prosthetic joint infection (PJI). Chronic PJI is commonly treated with two-stage exchange arthroplasty involving the placement of antibiotic-laden cement spacers (ACS) in the first stage, often containing nephrotoxic antibiotics. These patients often have significant comorbidity burdens and have higher rates of acute kidney injury (AKI). This systematic review aims to assess the current literature to identify (1) AKI incidence, (2) associated risk factors, and (3) antibiotic concentration thresholds in ACS that increase AKI risk following first-stage revision arthroplasty. METHODS: An electronic search was performed of the PubMed database of all studies involving patients undergoing ACS placement for chronic PJI. Studies assessing AKI rates and risk factors were screened by two authors independently. Data synthesis was performed when possible. Significant heterogeneity prevented meta-analysis. RESULTS: Eight observational studies consisting of 540 knee PJIs and 943 hip PJIs met inclusion criteria. There were 309 (21%) cases involving AKI. The most commonly reported risk factors included perfusion-related factors (lower preoperative hemoglobin, transfusion requirement, or hypovolemia), older age, increased comorbidity burden, and nonsteroidal anti-inflammatory drug consumption. Only two studies found increased risk with greater ACS antibiotic concentration (> 4 g vancomycin and > 4.8 g tobramycin per spacer in one study, > 3.6 g of vancomycin per batch or > 3.6 g of aminoglycosides per batch in the other); however, these were reported from univariate analyses not accounting for other potential risk factors. DISCUSSION: Patients undergoing ACS placement for chronic PJI are at an increased risk for AKI. Understanding the risk factors may lead to better multidisciplinary care and safer outcomes for chronic PJI patients.

Comparing five equations to calculate estimated glomerular filtration rate to predict acute kidney injury following total joint arthroplasty.

BACKGROUND: Acute kidney injury (AKI) following total joint arthroplasty (TJA) is associated with increased morbidity and mortality. Estimated glomerular filtration rate (eGFR) is used as an indicator of renal function. The purpose of this study was (1) to assess each of the five equations that are used in calculating eGFR, and (2) to evaluate which equation may best predict AKI in patients following TJA. METHODS: The National Surgical Quality Improvement Program (NSQIP) was queried for all 497,261 cases of TJA performed from 2012 to 2019 with complete data. The Modification of Diet in Renal Disease (MDRD) II, re-expressed MDRD II, Cockcroft-Gault, Mayo quadratic, and Chronic Kidney Disease Epidemiology Collaboration equations were used to calculate preoperative eGFR. Two cohorts were created based on the development of postoperative AKI and were compared based on demographic and preoperative factors. Multivariate regression analysis was used to assess for independent associations between preoperative eGFR and postoperative renal failure for each equation. The Akaike information criterion (AIC) was used to evaluate predictive ability of the five equations. RESULTS: Seven hundred seventy-seven (0.16%) patients experienced AKI after TJA. The Cockcroft-Gault equation yielded the highest mean eGFR (98.6 ± 32.7), while the Re-expressed MDRD II equation yielded the lowest mean eGFR (75.1 ± 28.8). Multivariate regression analysis demonstrated that a decrease in preoperative eGFR was independently associated with an increased risk of developing postoperative AKI in all five equations. The AIC was the lowest in the Mayo equation. CONCLUSIONS: Preoperative decrease in eGFR was independently associated with increased risk of postoperative AKI in all five equations. The Mayo equation was most predictive of the development of postoperative AKI following TJA. The mayo equation best identified patients with the highest risk of postoperative AKI, which may help providers make decisions on perioperative management in these patients.

Predictors of Hospice Discharge After Surgical Fixation of Hip Fractures.

BACKGROUND: Each year, over 300,000 people older than 65 years are hospitalized for hip fractures. Given the notable morbidity and mortality faced by elderly patients in the postinjury period, recommendations have been put forth for integrating palliative and, when needed, hospice care to improve patients' quality of life. Our objective was to (1) understand the proportion of patients discharged to hospice after hip fracture surgery and their 30-day mortality rates and (2) identify the independent predictors of discharge to hospice. METHODS: We retrospectively queried the American College of Surgeons National Surgical Quality Improvement Program for all hip fracture surgeries between the years of 2016 and 2018. Included cases were stratified into two cohorts: cases involving a discharge to hospice and nonhospice discharge. Variables assessed included patient demographics, comorbidities, perioperative characteristics, and postoperative outcomes. Differences between hospice and nonhospice patients were compared using chi-squared analysis or the Fisher exact test for categorical variables and Student t -tests for continuous variables. A binary logistic regression model was used to assess independent predictors of hospice discharge with 30-day mortality. RESULTS: Overall, 31,531 surgically treated hip fractures were identified, of which only 281 (0.9%) involved a discharge to hospice. Patients discharged to hospice had a 67% 30-day mortality rate in comparison with 5.6% of patients not discharged to hospice ( P < 0.001). Disseminated cancer, dependent functional status, >10% weight loss over 6 months preoperatively, and preoperative cognitive deficit were the strongest predictors of hospice discharge with 30-day mortality after hip fracture surgery. CONCLUSIONS: Current hospice utilization in hip fracture patients remains low, but 30-day mortality in these patients is high. An awareness of the associations between patient characteristics and discharge to hospice with 30-day mortality is important for surgeons to consider when discussing postoperative expectations and outcomes with these patients. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Transfusion Rates in the Operative Treatment of Prosthetic Hip and Knee Infection.

Surgery for prosthetic joint infection (PJI) can often lead to significant blood loss, necessitating allogeneic blood transfusion (ABT). The use of ABT is associated with higher rates of morbidity and death in revision total joint arthroplasty, particularly in the treatment of PJI. We compared ABT rates by procedure type among patients treated for PJI. We retrospectively reviewed 143 operative cases of hip and knee PJI performed at our institution between 2016 and 2018. Procedures were categorized as irrigation and debridement (I&D) with modular component exchange (modular component exchange), explantation with I&D and placement of an antibiotic spacer (explantation), I&D with antibiotic spacer exchange (spacer exchange), or antibiotic spacer removal and prosthetic reimplantation (reimplantation). Rates of ABT and the number of units transfused were assessed. Factors associated with ABT were assessed with a multilevel mixed-effects regression model. Of the cases, 77 (54%) required ABT. The highest rates of ABT occurred during explantation (74%) and spacer exchange (72%), followed by reimplantation (36%) and modular component exchange (33%). A lower preoperative hemoglobin level was associated with higher odds of ABT. Explantation, reimplantation, and spacer exchange were associated with greater odds of ABT. Antibiotic spacer exchange and explantation were associated with greater odds of multiple-unit transfusion. Rates of ABT remain high in the surgical treatment of PJI. Antibiotic spacer exchange and explantation procedures had high rates of multiple-unit transfusions, and additional units of blood should be made available. Preoperative anemia should be treated when possible, and further refinement of blood management protocols for prosthetic joint infection is necessary. [Orthopedics. 2022;45(6):353-359.].

Preoperative Patient Optimization in Total Joint Arthroplasty-The Paradigm Shift from Preoperative Clearance: A Narrative Review.

Background: Total joint arthroplasty (TJA) is one of the most common procedures performed in the United States. Outcomes of this elective procedure may be improved via preoperative optimization of modifiable risk factors. Purposes: We sought to summarize the literature on the clinical implications of preoperative risk factors in TJA and to develop recommendations regarding preoperative optimization of these risk factors. Methods: We searched PubMed in August 2019 with an update in September 2020 for English-language, peer-reviewed publications assessing the influence on outcomes in total hip and knee replacement of 7 preoperative risk factors-obesity, malnutrition, hypoalbuminemia, diabetes, anemia, smoking, and opioid use-and recommendations to mitigate them. Results: Sixty-nine studies were identified, including 3 randomized controlled trials, 8 prospective cohort studies, 42 retrospective studies, 6 systematic reviews, 3 narrative reviews, and 7 consensus guidelines. These studies described worse outcomes associated with these 7 risk factors, including increased rates of in-hospital complications, transfusions, periprosthetic joint infections, revisions, and deaths. Recommendations for strategies to screen and address these risk factors are provided. Conclusions: Risk factors can be optimized, with evidence suggesting the following thresholds prior to surgery: a body mass index <40 kg/m2, serum albumin ≥3.5 g/dL, hemoglobin A1C ≤7.5%, hemoglobin >12.0 g/dL in women and >13.0 g/dL in men, and smoking cessation and ≥50% decrease in opioid use by 4 weeks prior to surgery. Surgery should be delayed until these risk factors are adequately optimized.

A Novel Method for Stratification of Major Complication Risk Using Body Mass Index Thresholds for Patients Undergoing Total Hip Arthroplasty: A National Cohort of 224,413 Patients.

INTRODUCTION: Elevated body mass index (BMI) is associated with complications following Total Hip Arthroplasty (THA). Since obese individuals are almost 10 times more likely to require THA compared to non-obese individuals, we need to understand the risk-benefit continuum while considering THA in obese patients. We aimed to determine data-driven thresholds for BMI at which the risk of major complications following THA increases significantly. METHODS: Patients were identified in a national database who underwent primary THA from 2010 to 2020. BMI thresholds were identified using the stratum-specific likelihood ratio (SSLR) methodology, which is an adaptive technique that allows for identification of BMI cut-offs, at which the risk of major complications is increased significantly . BMI cutoffs identified using SSLR were used to create a logistic regression model. RESULTS: A total of 224,413 patients were identified with a mean age of 66 ± 10, BMI 32 ± 6.7, and 7,186 (3%) sustained a major complication. BMI thresholds were defined as 19-31, 32-37, 38-49 and 50+. Overall, the absolute risk of major complications increased from 2.9% in the lowest BMI strata to 7.5% in the highest BMI strata. Compared to patients with a BMI between 19-31, the odds of sustaining a major complication sequentially increased by 1.2, 1.6, and 2.5-times for patients in each higher BMI strata (all, P < .05). CONCLUSIONS: We have identified BMI cutoffs using SSLR that categorizes patients into four categories of risk for major complications in a nationally representative patient sample. These thresholds can be used in the surgical decision-making process between patients and surgeons.

Survey of sarcoma surgery principles among orthopaedic oncologists.

BACKGROUND: Surgical principles and techniques used during primary sarcoma excision focus on acquiring negative margins, reducing the risk of local recurrence, and minimizing contamination. These principles and techniques within orthopaedic oncology are not well documented in the literature. No standardized surgical hand-off or approach to education across disciplines on orthopaedic oncology principles and techniques has been published. Currently, education on intraoperative approaches is passed down by oral tradition. OBJECTIVES: Our objective was to survey members of the Musculoskeletal Tumor Society (MSTS) to identify their core principles and practices in orthopaedic oncology. We aimed to 1) provide descriptive analyses of surgeon technique patterns; 2) determine correlations between individual practice patterns; and 3) identify distinct clusters of surgeons on the basis of common practice tendencies. METHODS: A web-based, 16-question survey regarding orthopaedic oncology intraoperative principles and techniques was distributed online to all 349 members of the MSTS in 2021. There were 137 (39%) unique respondents, all of whom completed the entire survey. The 16 survey questions were grouped into 4 key aspects of sarcoma excision: pre-incision, exposure of the mass, delivery of the mass, and closure. The questions inquired about respondent preference on draping, back table setup, instrument use, and intraoperative decision making. These questions were selected on the basis of existing reports, as well as the senior author's experience. We analyzed the responses using 3 methods: 1) descriptive statistics, 2) correlations between question responses, and 3) clustering analysis. We used an artificial intelligence-based clustering algorithm to cluster respondents according to their practice patterns. The results of our correlation analyses are reported as Spearman's rho (ρ) correlation coefficients. RESULTS: Most respondents (mean, 71%; standard deviation, 22%) reported using the described surgical techniques "most of the time" or "in all cases." A strong positive correlation was found between respondents who answered "yes" to both of the following questions: "Do you change your surgical gloves after passing off the tumor specimen?" and "Does your entire surgical team change their gloves after passing off the tumor specimen?" (ρ = 0.88). A moderate positive correlation was found between those who answered "yes" to both of the following questions: "Do you change your surgical gloves after passing off the tumor specimen (i.e., prior to closure)?" and "Do you use new and/or unused surgical instruments for the final closure?" (ρ = 0.60). The cluster analysis identified 3 distinct clusters of respondents. The conservative technique cluster (N = 42) was more likely to answer "yes" to 9 of the 10 questions regarding incision management, consultant team communication, gloving, and instrument use, whereas the permissive technique cluster (N = 41) was more likely to answer "no" to questions regarding gloving, draping, and instrument use. CONCLUSIONS: Our findings indicate that most respondents perform the surveyed techniques, and there is homogeneity in the practice patterns of members of the MSTS; however, we identified distinct clusters of respondents who were significantly more likely to perform certain techniques. These results support establishing a standardized set of intraoperative techniques and formal surgical education regarding intraoperative principles and techniques in orthopaedic oncology.

Preoperative Hypoalbuminemia Is Associated With Early Morbidity and Mortality After Revision Total Hip Arthroplasty.

Hypoalbuminemia is associated with early morbidity and mortality in revision total knee arthroplasty. We evaluated the effect of preoperative hypoalbuminemia on 30-day morbidity and mortality in revision total hip arthroplasty (THA). The National Surgical Quality Improvement Program (NSQIP) database was queried from 2015 to 2018 to identify patients who underwent revision THA. Patients were stratified based on the presence or absence of preoperative hypoalbuminemia and their odds of a major complication or death within 30 days of revision THA with multivariate logistic regression. After Bonferroni correction for these 2 primary outcomes, statistical significance was defined as P<.025. A total of 2492 revision THAs with complete data were identified, of which 486 (20%) had preoperative hypoalbuminemia. Preoperative hypoalbuminemia increased the absolute risk of a major complication by 15.3% compared with patients with revision THA without hypoalbuminemia (30% vs 14.7%, P<.001). Patients with preoperative hypoalbuminemia also had nearly a 7-fold higher incidence of death (3.3%) compared with those with revision THA without preoperative hypoalbuminemia (0.5%, P<.001). After logistic regression, the odds of having a major complication after revision THA with preoperative hypoalbuminemia within 30 days were increased by 80% (odds ratio, 1.8; 95% CI, 1.4-2.3; P<.001), and the odds of death within 30 days were increased by 210% (odds ratio, 3.1; 95% CI, 1.2-7.8; P=.020). Hypoalbuminemia is associated with early morbidity and mortality after revision THA. [Orthopedics. 2022;45(5):281-286.].

Outpatient Simultaneous Bilateral Total Knee Arthroplasty: Is It Safe?

BACKGROUND: It is currently unknown if simultaneous bilateral total knee arthroplasty (si-BTKA) can also be safely performed in the outpatient setting. The primary aim of this study was to compare 30-day postoperative complication rates between outpatient and inpatient si-BTKA. METHODS: Adults undergoing simultaneous bilateral total knee arthroplasty (si-BTKA) from 2015-2019 were queried using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Our primary analysis compared the rates of complications between outpatient si-BTKA and inpatient si-BTKA using bivariate comparisons and multivariable logistic regression of outpatient and inpatient cases controlling for differences in baseline demographics and comorbidities. RESULTS: From 2015 to 2019, the utilization of outpatient si-BTKA increased from 0.6% to 10.5%. Outpatient si-BTKA were found to have significantly lower odds of any complication (OR = 0.49), minor complication (OR = 0.50), and postoperative transfusion (OR = 0.66) compared to inpatient cases. Outpatient si-BTKA also had a significantly shorter operative time. CONCLUSION: Compared to inpatient si-BTKA, patients who undergo outpatient si-BTKA do not demonstrate increased rates of any complication, severe complications, and minor complications within 30-days postoperatively. Further insight is needed on the effect of outpatient si-BTKA on long-term outcomes.

Regional or Neuraxial Anesthesia May Help Mitigate the Effects of Bone Cement Implantation Syndrome in Patients Undergoing Cemented Hip and Knee Arthroplasty for Oncologic Indications.

INTRODUCTION: Bone cement implantation syndrome (BCIS) occurs during and after cementation of implants and is associated with hypotension, hypoxia, and cardiovascular collapse. In this study, we aimed to identify risk factors and potential mitigating factors of BCIS in the oncologic adult cohort undergoing cemented arthroplasty. METHODS: We retrospectively reviewed oncologic patients aged 18 years or older who underwent cemented arthroplasty of either the hip or knee from 2015 to 2020. All implants were stemmed. We classified BCIS into three separate categories: (1) grade 1: intraoperative moderate hypoxia (<94%) or drop in systolic blood pressure >20%; (2) grade 2: intraoperative severe hypoxia or drop in systolic blood pressure >40%; and (3) grade 3: cardiovascular collapse requiring cardiopulmonary resuscitation. Demographics, primary malignancy diagnosis, intraoperative factors including cement timing, development of BCIS, 30-day postoperative outcomes, and mortality up to 2 years postoperatively were evaluated. Bivariate analyses and multivariate logistic regression were performed. RESULTS: Sixty-seven patients met inclusion criteria. Of these, 31 patients (46%) developed BCIS. No difference was found in age (65.5 versus 60.9 years; P = 0.15) or body mass index (28.8 kg/m2 versus 29.3 kg/m2; P = 0.76), comorbidities, intraoperative factors, or postoperative surgical outcomes between those who developed BCIS and those who did not (all; P > 0.05). An association with the type of anesthesia administered and development of BCIS in patients receiving general anesthesia alone (17/24 patients, 71%), neuraxial and general (4/15 patients, 27%), and regional and general anesthesia (10/28 patients 36%, P = 0.01) was found. Compared With neuraxial and regional anesthesia, general anesthesia alone had 5.8 (P = 0.007) and 4.5 times (P = 0.006) greater odds of developing BCIS, respectively. No differences were noted in rates of BCIS between regional and neuraxial anesthesia (P = 0.81). DISCUSSION: Addition of regional or neuraxial anesthesia may be protective in reducing development of BCIS in the orthopaedic oncologic cohort undergoing hip and knee arthroplasty. LEVEL OF EVIDENCE: III.

Predictors and Outcomes of Postoperative Hemoglobin of <8 g/dL in Total Joint Arthroplasty.

BACKGROUND: Restrictive transfusion practices have decreased transfusions in total joint arthroplasty (TJA). A hemoglobin threshold of <8 g/dL is commonly used. Predictors of this degree of postoperative anemia in TJA and its association with postoperative outcomes, independent of transfusions, remain unclear. We identified predictors of postoperative hemoglobin of <8 g/dL and outcomes with and without transfusion in TJA. METHODS: Primary elective TJA cases performed with a multimodal blood management protocol from 2017 to 2018 were reviewed, identifying 1,583 cases. Preoperative and postoperative variables were compared between patients with postoperative hemoglobin of <8 and ≥8 g/dL. Logistic regression and receiver operating characteristic curves were used to assess predictors of postoperative hemoglobin of <8 g/dL. RESULTS: Positive predictors of postoperative hemoglobin of <8 g/dL were preoperative hemoglobin level (odds ratio [OR] per 1.0-g/dL decrease, 3.0 [95% confidence interval (CI), 2.4 to 3.7]), total hip arthroplasty (OR compared with total knee arthroplasty, 2.1 [95% CI, 1.3 to 3.4]), and operative time (OR per 30-minute increase, 2.0 [95% CI, 1.6 to 2.6]). Negative predictors of postoperative hemoglobin of <8 g/dL were tranexamic acid use (OR, 0.42 [95% CI, 0.20 to 0.85]) and body mass index (OR per 1 kg/m2 above normal, 0.90 [95% CI, 0.86 to 0.94]). Preoperative hemoglobin levels of <12.4 g/dL in women and <13.4 g/dL in men best predicted postoperative hemoglobin of <8 g/dL. Overall, 5.2% of patients with postoperative hemoglobin of 7 to 8 g/dL and 95% of patients with postoperative hemoglobin of <7 g/dL received transfusions. Patients with postoperative hemoglobin of <8 g/dL had longer hospital stays (p < 0.001) and greater rates of emergency department visits or readmissions (p = 0.001) and acute kidney injury (p < 0.001). Among patients with postoperative hemoglobin of <8 g/dL, patients who received transfusions had a lower postoperative hemoglobin nadir (p < 0.001) and a longer hospital stay (p = 0.035) than patients who did not receive transfusions. CONCLUSIONS: Postoperative hemoglobin of <8 g/dL after TJA was associated with worse outcomes, even for patients who do not receive transfusions. Optimizing preoperative hemoglobin levels may mitigate postoperative anemia and adverse outcomes. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Extremity fasciotomy for patients on extracorporeal membrane oxygenation is independently associated with inpatient mortality.

INTRODUCTION: Extracorporeal membrane oxygenation (ECMO) maintains end-organ perfusion in critically ill patients with cardiac or respiratory failure; however, ECMO cannulation in the extremities has been associated with significant limb ischemia and risk of compartment syndrome. Current literature on ECMO and fasciotomies is limited to small single-center retrospective studies. This study aimed to (1) compare the incidence of postoperative outcomes and mortality in patients undergoing fasciotomy while on ECMO to those of non-fasciotomy ECMO patients, and (2) assess the difference in adjusted mortality risk between the two groups. HYPOTHESIS: We hypothesized that patients undergoing fasciotomy while on ECMO would have significantly higher odds of in-hospital mortality than non-fasciotomy ECMO patients after adjustment for perioperative variables. METHODS: We conducted a retrospective review of NIS from January 1st, 2012-September 30, 2015 for all hospitalizations involving ECMO and stratified them into two cohorts based on whether they underwent fasciotomy after ECMO. Patient baseline characteristics, in-hospital procedures, and postoperative outcomes were compared between the two cohorts. Logistic regression was used to assess in-hospital mortality risk between the two cohorts adjusting for age, sex, Elixhauser score, and perioperative procedures and non-fasciotomy perioperative morbidity. RESULTS: There were 7,085 estimated eligible discharges between 2012 and 2015 identified, 149 (2.1%) of which underwent fasciotomy following ECMO. One hundred and thirteen of the 149 hospitalizations (77%) in the fasciotomy cohort resulted in in-hospital mortality, compared to 3,805 of the 6,936 (55%) in the non-fasciotomy cohort. There were no differences in rates of transfusion (p=0.290), length of stay (p=0.282), or discharge disposition (p=0.126) between the two cohorts. In the logistic regression model, the fasciotomy cohort had a higher odds of in-hospital mortality than non-fasciotomy cohort (OR, 2.5; 95% CI, 1.1-5.6). DISCUSSION: Operative treatment of acute compartment syndrome for patients on ECMO therapy is associated with significantly increased mortality and morbidity. Whether fasciotomy is a marker of sickness or represents a cause-and-effect relationship is unknown and future should investigate the role of non-operative treatment of compartment syndrome on mortality in this population. LEVEL OF EVIDENCE: III; Prognostic.

Iatrogenic Metastasis of Soft-tissue Sarcoma at the Donor Flap Site: Case Report and Proposed Surgical Oncologic Techniques.

An 81-year-old woman with multiply recurrent undifferentiated pleomorphic sarcoma of the foot underwent wide excision and reconstruction with an anterolateral thigh free flap. Six years postoperatively, she developed biopsy-proven recurrence within the harvest site. No other sites of disease were detected on staging workup. The flap site recurrence was attributed to iatrogenic implantation at the time of harvesting. Iatrogenic metastases are thought to be caused by tumor implantation, which may be attributable to cross-contamination from instrumentation and surgical techniques. In the present article, we highlight preventive techniques and oncologic surgical principles intended to reduce the likelihood of iatrogenic metastasis. Increased awareness by all members of the surgical team may prevent this unfortunate complication.

Septic Arthritis Among Users of Injection Drugs: Clinical Course and Microbial Characteristics.

Injection drug use (IDU) is a risk factor for septic arthritis (SA) of native joints. Amid the opioid crisis, IDU rates have increased. This study assessed differences in pre-operative characteristics, microbial characteristics, and postoperative outcomes of 177 cases of SA treated operatively from 2015 to 2019 at 3 US hospitals, by self-reported IDU status. Forty cases (23%) involved patients who reported IDU. Patient characteristics, comorbidities, microbial characteristics, duration of hospital stay, discharge destination, follow-up rates, and rates of persistent/secondary infection were compared by self-reported IDU status. Compared with non-IDU-associated SA (non-IDU-SA), IDU-associated SA (IDU-SA) was associated with female sex (P=.001), younger age (P<.001), lower body mass index (P<.001), tobacco use (P<.001), and psychiatric diagnosis (P=.04) and was more likely to involve methicillin-resistant Staphylococcus aureus (P<.001). The IDU-SA was associated with discharge to a skilled nursing facility or against medical advice (P<.001) and with loss to follow-up (P=.01). The 2 groups did not differ in terms of American Society of Anesthesiologists classification, joint involved, Gram stain positivity, presence of bacteremia, peripherally inserted central catheter placement, return to hospital within 3 months, or persistent/secondary positive results on culture within 3 months. Patients with IDU-SA were younger, were more likely to be female, had lower body mass index, and had fewer medical comorbidities but were more likely to use tobacco and to have a psychiatric diagnosis compared with patients with non-IDU-SA. Methicillin-resistant S aureus was more common in the IDU-SA group, as was discharge to a skilled nursing facility or against medical advice. Patients with IDU-SA were less likely to return for follow-up than patients with non-IDU-SA. [Orthopedics. 2021;44(6):e747-e752.].

Reducing unnecessary crossmatching for hip fracture patients by accounting for preoperative hemoglobin concentration.

BACKGROUND: Maximum surgical blood order schedules were designed to eliminate unnecessary preoperative crossmatching prior to surgery in order to conserve blood bank resources. Most protocols recommend type and cross of 2 red blood cell (RBC) units for patients undergoing surgery for treatment of hip fracture. Preoperative hemoglobin has been identified as the strongest predictor of inpatient transfusion, but current maximum surgical blood order schedules do not consider preoperative hemoglobin values to determine the number of RBC units to prepare prior to surgery. AIM: To determine the preoperative hemoglobin level resulting in the optimal 2:1 crossmatch-to-transfusion (C:T) ratio in hip fracture surgery patients. METHODS: In 2015 a patient blood management (PBM) program was implemented at our institution mandating a single unit-per-occurrence transfusion policy and a restrictive transfusion threshold of < 7 g/dL hemoglobin in asymptomatic patients and < 8 g/dL in those with refractory symptomatic anemia or history of coronary artery disease. We identified all hip fracture patients between 2013 and 2017 and compared the preoperative hemoglobin which would predict a 2:1 C:T ratio in the pre PBM and post PBM cohorts. Prediction profiling and sensitivity analysis were performed with statistical significance set at P < 0.05. RESULTS: Four hundred and ninety-eight patients who underwent hip fracture surgery between 2013 and 2017 were identified, 291 in the post PBM cohort. Transfusion requirements in the post PBM cohort were lower (51% vs 33%, P < 0.0001) than in the pre PBM cohort. The mean RBC units transfused per patient was 1.15 in the pre PBM cohort, compared to 0.66 in the post PBM cohort (P < 0.001). The 2:1 C:T ratio (inpatient transfusion probability of 50%) was predicted by a preoperative hemoglobin of 12.3 g/dL [area under the curve (AUC) 0.78 (95% confidence interval (CI), 0.72-0.83), Sensitivity 0.66] in the pre PBM cohort and 10.7 g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.88] in the post PBM cohort. A 50% probability of requiring > 1 RBC unit was predicted by 11.2g/dL [AUC 0.80 (95%CI, 0.74-0.85), Sensitivity 0.87] in the pre PBM cohort and 8.7g/dL [AUC 0.78 (95%CI, 0.73-0.83), Sensitivity 0.84] in the post-PBM cohort. CONCLUSION: The hip fracture maximum surgical blood order schedule should consider preoperative hemoglobin in determining the number of units to type and cross prior to surgery.

Incidence, mortality, and complications of acute myocardial infarction with and without percutaneous coronary intervention in hip fracture patients.

INTRODUCTION: Acute myocardial infarction (AMI) is a common cause of death following hip fracture surgery. This study aimed to determine the incidence and timing of perioperative AMI treated with percutaneous coronary intervention (PCI) in hip fracture patients, and to compare in-hospital mortality and complications between hip fracture patients who did not have an AMI, those who sustained a perioperative AMI and did not undergo PCI, and those who sustained an AMI and underwent PCI. METHODS: The National Inpatient Sample (NIS) was queried from 2010 through the third quarter of 2015 to identify all patients undergoing hip fracture surgery. Patients were stratified into three cohorts: perioperative AMI but no PCI (no PCI cohort), perioperative AMI with PCI (PCI cohort), and no perioperative AMI or PCI (no AMI cohort). Patient demographics, comorbidities, in-hospital mortality, and complications were compared between cohorts. Multivariable logistic regression adjusting for age, sex, procedure, and Elixhauser score was used to assess the relative odds of in-hospital mortality for each cohort. RESULTS: A total of 1,535,917 hip fracture cases were identified, with 1.9% in the no PCI cohort, 0.01% in the PCI cohort, and 98.0% in the no AMI cohort. In-hospital mortality was lower in the PCI cohort than in the no PCI cohort (8.8% vs. 14%), and was greater for both than in the no AMI cohort (1.6%, p < 0.001 for all). Both the no PCI cohort (OR, 6.1; 95% CI, 5.6-6.6) and PCI cohort (OR, 4.1; 95% CI, 2.8-6.0) had increased adjusted odds of in-hospital mortality compared to the no AMI cohort. The PCI cohort had a higher rate of bleeding complications than both other cohorts, and the no PCI cohort had a higher rate of transfusion than both other cohorts. CONCLUSIONS: Perioperative AMI both with and without PCI independently increases the risk of mortality in hip fracture patients, with the highest risk of mortality in those with AMI without PCI. Providers should understand the increased morbidity and mortality associated with AMI in hip fracture patients, as well as the risks and benefits of perioperative PCI, in order to better counsel and manage these patients. LEVEL OF EVIDENCE: III.

Free Falling: Declining Inflation-Adjusted Payment for Arthroplasty Surgeons.

BACKGROUND: Over the past decade, there have been ongoing concerns over declining surgeon compensation for lower extremity arthroplasty. We aimed to determine changes in surgeon payment, patient charges, and overall reimbursement rates for patients undergoing unicompartmental arthroplasty (UKA) and both primary and revision total knee (TKA) and hip (THA) arthroplasty. METHODS: Using Medicare data from 2012 to 2017, we determined inflation-adjusted changes in annual surgeon payment (professional fee), patient charges, and reimbursement rate (payment-to-charge ratio) for UKA and primary/revision TKA and THA. Both nonweighted and weighted (by procedure frequency/volume) means were calculated. RESULTS: Inflation-adjusted surgeon payment decreased for all procedures analyzed, with primary TKA (-17%) and THA (-11%) falling the most. Payment for UKA increased the most (+30%). There was a small increase in charges for THA revision (+2.2%, +2.1%, and +3.2% for acetabulum only, femur only, and both components, respectively). Charges for primary TKA (-3.7%) and THA (-1.5%) decreased slightly. The reimbursement rate for all procedures fell with UKA (-15%), TKA (-14%), and THA (-10%) falling the most. After weighting by procedure frequency/volume and combining all surgeries, average charges fell slightly (-0.7%), whereas surgeon payment (-13%) and reimbursement rate (-12%) fell more sharply. CONCLUSION: Although patient charges have grown in pace with the inflationary rate for primary and revision TKA and THA, surgeon payment and reimbursement rates have fallen sharply. The orthopedic community needs to be aware of these financial trends to communicate to payers and health care policy makers the importance of protecting a sustainable payment infrastructure.

Impact of Compensated Cirrhosis Etiology on Postoperative Outcomes Following Total Knee Arthroplasty.

BACKGROUND: Cirrhotics often demonstrate worse outcomes than their non-cirrhotic counterparts following orthopedic surgery; however, there are limited arthroplasty-focused data on this occurrence. Additionally, variances in postoperative outcomes among the different etiologies of cirrhosis have not been well described. The aim of this study is to evaluate the effect compensated cirrhosis had on postoperative outcomes following elective total knee arthroplasty (TKA). METHODS: In total, 1,734,568 patients who underwent primary TKA from 2006 to 2013 were identified using the Medicare Claims Database. Patients were divided into those with a history of compensated cirrhosis and those with no history of liver disease. Subgroup analysis was performed based on the etiology of cirrhosis. Multivariate logistic regression was used to evaluate postsurgical outcomes of interest. RESULTS: Cirrhotic patients had higher risk of developing disseminated intravascular coagulation (odds ratio [OR] 2.76, P = .003), encephalopathy (OR 3.00, P < .001), and periprosthetic infection (OR 1.79, P < .001) compared to controls. Following subgroup analysis, alcoholic cirrhotics had high risk of periprosthetic infection (OR 2.12, P < .001), fracture (OR 3.28, P < .001), transfusion (OR 2.45, P < .001), and encephalopathy (OR 7.34, P < .001) compared to controls. Viral cirrhosis was associated with an increase in 90-day charges ($14,941, P < .001) compared to controls, while cirrhosis secondary to other causes was associated with few adverse outcomes compared to controls. CONCLUSION: Liver cirrhosis is an independent risk factor for increased perioperative morbidity and financial burden following TKA. Cirrhosis due to etiologies other than viral infections and alcoholism are associated with few adverse outcomes. Surgeons should be aware of these complications to properly optimize postoperative management.

Factors Associated With Perioperative Transfusion in Lower Extremity Revision Arthroplasty Under a Restrictive Blood Management Protocol.

INTRODUCTION: Approximately 37% of patients undergoing lower extremity revision total joint arthroplasty (TJA) receive allogeneic blood transfusions (ABTs), which are associated with increased risk of morbidity and death. It is important to identify patient factors associated with needing ABT because the health of higher-risk patients can be optimized preoperatively and their need for ABT can be minimized. Our goal was to identify the patient and surgical factors independently associated with perioperative ABT in revision TJA. METHODS: We included all 251 lower extremity revision TJA cases performed at our academic tertiary care center from January 1, 2016, to December 31, 2018. We assessed the following factors for associations with perioperative ABT: patient age, sex, race, body mass index, preoperative hemoglobin level, and infection status (ie, infection as indication for revision TJA); use of vasopressors, tranexamic acid (TXA), surgical drains, tourniquets, and intraoperative cell salvage; and procedure type (hip versus knee), procedure complexity (according to the number of components revised), and surgical time. Multivariable regression was used to identify factors independently associated with perioperative ABT. RESULTS: The following characteristics were independently associated with greater odds of perioperative ABT: preoperative hemoglobin level (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.5 to 2.2), infectious indication for revision (OR, 3.6; 95% CI, 1.3 to 9.7), and procedure complexity. TXA use was a negative predictor of ABT (OR, 0.47; 95% CI, 0.23 to 0.98). Compared with polyethylene liner exchanges, single-component revisions (OR, 14; 95% CI, 3.6 to 56) and dual-component revisions (OR, 7.8; 95% CI, 2.3 to 26) were associated with greater odds of ABT. DISCUSSION: Patients with preoperative anemia, those undergoing revision TJA because of infection, those who did not receive TXA, and those undergoing more complex TJA procedures may have greater odds of requiring ABT. We recommend preoperative optimization of the health of these patients to reduce the need for ABT. LEVEL OF EVIDENCE: Level III, prognostic study.

Complications and 30-Day Mortality Rate After Hip Fracture Surgery in Superobese Patients.

OBJECTIVE: Paradoxically, overweight and obesity are associated with lower odds of complications and death after hip fracture surgery. Our objective was to determine whether this "obesity paradox" extends to patients with "superobesity." In this study, we compared rates of complications and death among superobese patients with those of patients in other body mass index (BMI) categories. METHODS: Using the National Surgical Quality Improvement Program database, we identified >100,000 hip fracture surgeries performed from 2012 to 2018. Patients were categorized as underweight (BMI <18.5), normal weight (BMI 18.5-24.9), overweight (BMI 25-29.9), obese (BMI 30-39.9), morbidly obese (BMI 40-49.9), or superobese (BMI ≥50). We analyzed patient characteristics, surgical characteristics, and 30-day outcomes. Using multivariate regression with normal-weight patients as the referent, we determined odds of major complications, minor complications, and death within 30 days by BMI category. RESULTS: Of 440 superobese patients, 20% had major complications, 33% had minor complications, and 5.2% died within 30 days after surgery. When comparing patients in other BMI categories with normal-weight patients, superobese patients had the highest odds of major complications [odds ratio (OR): 1.6, 95% confidence interval (CI), 1.2-2.0] but did not have significantly different odds of death (OR: 0.91, 95% CI, 0.59-1.4) or minor complications (OR: 1.2, 95% CI, 0.94-1.4). CONCLUSION: Superobese patients had significantly higher odds of major complications within 30 days after hip fracture surgery compared with all other patients. This "obesity paradox" did not apply to superobese patients. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a Complete Description of Levels of Evidence.