Risk factors for early mortality following modern total hip arthroplasty

What Factors Influence In-Hospital Mortality Following Aseptic Revision Total Hip Arthroplasty? A Single-Center Analysis of 13,203 Patients

BACKGROUND

Revision total hip arthroplasty (rTHA) is associated with an extended surgical period, an increased hospitalization period, expanded blood loss, and high mortality rates. The purpose of the present study was to assess the risk factors that contribute to in-hospital mortality following aseptic rTHA.

METHODS

We performed a retrospective examination of the medical records of all patients who underwent elective rTHA surgery at our tertiary referral arthroplasty center between March 1996 and March 2019. The study involved a group of 13,203 patients, including 70 who expired during hospitalization and 13,133 in the control group. Baseline characteristics, medical history, comorbidities, and surgery-related parameters of the patients were recorded. Logistic regression analyses were performed to examine the association between independent variables and in-hospital mortalities, which were presented as odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Patient factors associated with in-hospital mortality included hepatitis C (OR 75.5, 95% CI 3.5 to 1,625.2), chronic obstructive pulmonary disease (OR 30.7, 95% CI 6.5 to 145.7), rheumatoid arthritis (OR 28.9, 95% CI 3.8 to 218.5), history of myocardial infarction (OR 24.9, 95% CI 4.4 to 140.8), history of cerebrovascular disease (OR 23.1, 95% CI 3.8 to 142), congestive heart failure (OR 18.9, 95% CI 3.8 to 94.2), and diabetes mellitus (OR 10.2, 95% CI 2.4 to 42.6). Surgical factors included the history of multiple prior revisions (OR 1.75, 95% CI 1.1 to 2.7), postoperative blood transfusion (OR 2.8, 95% CI 1.1 to 7.3), and decreased preoperative hemoglobin (OR 2.3, 95% CI 1.7 to 3.1).

CONCLUSIONS

Several patient-related and intraoperative factors significantly increased the risk of in-hospital mortality following aseptic rTHA. Vigilance and close perioperative monitoring are essential for patients undergoing this complex surgery.

LEVEL OF EVIDENCE

III.

What enhances the in-hospital mortality following total hip arthroplasty? A national inpatient sample-based study

PURPOSE

With prolonged life expectancy and advancements in prosthetic designs, the proportion of patients belonging to diverse age groups undergoing total hip arthroplasty (THA) has progressively increased. In this context, the details regarding risk factors associated with mortality after THA, and its prevalence need to be clearly understood. This study sought to identify the possible co-morbidities associated with post-THA mortality.

METHODS

Based on Nationwide Inpatient Sample (NIS) database, patients undergoing THA from 2016 to 2019 (using ICD-10CMP) were identified. The included cohort was stratified into two groups: "early mortality" and "no mortality" groups. The data regarding patients' demographics, co-morbidities, and associated complications were compared between the groups.

RESULTS

Overall, 337,249 patients underwent THA, among whom, 332 (0.1%) died during their hospital admission ("early mortality" group). The remaining patients were included under "no mortality" group (336,917 patients). There was significantly higher mortality in the patients, who underwent emergent THA (as compared with elective THA: odd's ratio 0.075; p < 0.001). Based on multivariate analysis, presence of liver cirrhosis, chronic kidney disease (CKD) and previous history of organ transplant increased the odds of mortality {odds ratio [Exp (B)]} after THA by 4.66- (p < 0.001), 2.37-fold (p < 0.001) and 1.91-fold (p = 0.04), respectively. Among post-THA complications, acute renal failure (ARF), pulmonary embolism (PE), pneumonia, myocardial infarction (MI), and prosthetic dislocation increased the odds of post-THA mortality by 20.64-fold (p < 0.001), 19.35-fold (p < 0.001), 8.21-fold (p < 0.001), 2.71-fold (p = 0.05) and 2.54-fold (p < 0.001), respectively.

CONCLUSION

THA is a safe surgery with low mortality rate during early post-operative period. Cirrhosis, CKD, and previous history of organ transplant were the most common co-morbidities associated with post-THA mortality. Among post-operative complications, ARF, PE, pneumonia, MI, and prosthetic dislocation substantially enhanced the odds of post-THA mortality.

Child-Pugh Class B or C Liver Disease Increases the Risk of Early Mortality in Patients With Hepatitis C Undergoing Elective Total Joint Arthroplasty Regardless of Treatment Status

BACKGROUND

Patients with hepatitis C virus (HCV) undergoing primary elective total joint arthroplasty (TJA) are at increased risk of postoperative complications. Patients with chronic liver disease and cirrhosis, specifically Child-Pugh Class B and C, who are undergoing general surgery have high 2-year mortality risks, approaching 60% to 80%. However, the role of Child-Pugh and Model for End-Stage Liver Disease classifications of liver status in predicting survivorship among patients with HCV undergoing elective arthroplasty has not been elucidated.

QUESTION/PURPOSE

What factors are independently associated with early mortality (< 2 years) in patients with HCV undergoing arthroplasty?

METHODS

We performed a retrospective study at three tertiary academic medical centers and identified patients with HCV undergoing primary elective TJA between January 2005 and December 2019. Patients who underwent revision TJA and simultaneous primary TJA were excluded. A total of 226 patients were eligible for inclusion in the study. A further 25% (57) were excluded because they were lost to follow-up before the minimum study requirement of 2 years of follow-up or had incomplete datasets. After the inclusion and exclusion criteria were applied, the final cohort consisted of 75% (169 of 226) of the initial patient population eligible for analysis. The mean follow-up duration was 53 ± 29 months. We compared confounding variables for mortality between patients with early mortality (16 patients) and surviving patients (153 patients), including comorbidities, HCV and liver characteristics, HCV treatment, and postoperative medical and surgical complications. Patients with early postoperative mortality were more likely to have an associated advanced Child-Pugh classification and comorbidities including peripheral vascular disease, end-stage renal disease, heart failure, and chronic obstructive pulmonary disease. However, both groups had similar 90-day and 1-year medical complication risks including myocardial infarction, stroke, pulmonary embolism, and reoperations for periprosthetic joint infection and mechanical failure. A multivariable regression analysis was performed to identify independent factors associated with early mortality, incorporating all significant variables with p < 0.05 present in the univariate analysis.

RESULTS

After accounting for significant variables in the univariate analysis such as peripheral vascular disease, end-stage renal disease, heart failure, chronic obstructive pulmonary disease, and liver fibrosis staging, Child-Pugh Class B or C classification was found to be the sole factor independently associated with increased odds of early (within 2 years) mortality in patients with HCV undergoing elective TJA (adjusted odds ratio 29 [95% confidence interval 5 to 174]; p < 0.001). The risk of early mortality in patients with Child-Pugh Class B or C was 64% (seven of 11) compared with 6% (nine of 158) in patients with Child-Pugh Class A (p < 0.001).

CONCLUSION

Patients with HCV and a Child-Pugh Class B or C at the time of elective TJA had substantially increased odds of death, regardless of liver function, cirrhosis, age, Model for End-Stage Liver Disease level, HCV treatment, and viral load status. This is similar to the risk of early mortality observed in patients with chronic liver disease undergoing abdominal and cardiac surgery. Surgeons should avoid these major elective procedures in patients with Child-Pugh Class B or C whenever possible. For patients who feel their arthritic symptoms and pain are unbearable, surgeons need to be clear that the risk of death is considerably elevated.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Neuraxial Anesthesia Significantly Reduces 30-Day Venous Thromboembolism Rate and Length of Hospital Stay in Primary Total Hip Arthroplasty: A Stratified Propensity Score-Matched Cohort Analysis

BACKGROUND

General anesthesia (GA) has been the commonly used protocol for total hip arthroplasty (THA); however, neuraxial anesthesia (NA) has been increasingly performed. Our purpose was to compare NA and GA for 30-day postoperative outcomes in United States veterans undergoing primary THA.

METHODS

A large veteran's database was utilized to identify patients undergoing primary THA between 1999 and 2019. A total of 6,244 patients had undergone THA and were included in our study. Of these, 44,780 (79.6%) had received GA, and 10,788 (19.2%) had received NA. Patients receiving NA or GA were compared for 30-day mortalities, cardiovascular, respiratory, and renal complications, and wound infections and hospital lengths of stay (LOS). Propensity score matching, multivariate regression analyses, and subgroup analyses by American Society of Anesthesiology classification were performed to control for selection bias and patient baseline characteristics.

RESULTS

Upon propensity-adjusted multivariate analyses, NA was associated with decreased risks for deep venous thrombosis (odds ratio [OR] = 0.63; 95% CI = 0.4-0.9; P = .02), any respiratory complication (OR = 0.63; 95% CI = 0.5-0.9; P = .003), unplanned reintubation (OR = 0.51; 95% CI = 0.3-0.9; P = .009), and prolonged LOS (OR = 0.78; 95% CI = 0.72-0.84; P < .001). Subgroup analyses by American Society of Anesthesiology classes showed NA decreased 30-day venous thromboembolism rate in low-risk (class I/II) patients and decreased respiratory complications in high-risk (class III/IV) patients.

CONCLUSION

Using a patient cohort obtained from a large national database, NA was associated with reduced risk of 30-day adverse events compared to GA in patients undergoing THA. Postoperative adverse events were decreased with NA administration with similar decreases observed across all patient preoperative risk levels. NA was also associated with a significant decrease in hospital LOS.

What Is the 30-Day Mortality Burden After Elective Total Hip Arthroplasty? An Analysis of 194,062 Patients

BACKGROUND

This study aims to answer the following questions regarding elective total hip arthroplasty (THA): What is (1) the overall 30-day mortality rate; (2) the mortality rate when stratified by age, comorbidities, and preoperative diagnosis; and (3) the distribution of patient demographics, comorbidities, and preoperative diagnoses between the mortality and mortality-free cohorts?

METHODS

The American College of Surgeons National Surgical Quality Improvement Program database was reviewed for all patients undergoing elective primary THA (2011-2018). A total of 194,062 patients were categorized based on the incidence of 30-day mortality (mortality: n = 206 vs mortality-free: n = 193,856). Patient demographics, comorbidities, and preoperative diagnosis (osteoarthritis [OA] vs non-OA) were recorded. Age category, American Society of Anesthesiologists (ASA) score, and modified Charlson Comorbidity Index (CCI) scores were normalized per 1000 and stratified by preoperative diagnosis.

RESULTS

The 30-day mortality rate was 0.11%. The percentage of deaths per age group (normalized per 1000) was 0% (18-29 years), 0% (30-39 years), 0.049% (40-49 years), 0.052%(50-59 years), 0.071% (60-69 years), 0.133% (70-79 years), and 0.352% (80-89 years). The percentage of deaths per ASA score was 0% (ASA I), 0.035% (ASA II), 0.174% (ASA III), and 1.008% (ASA IV). The percentage of deaths per CCI score was 0.09% (CCI = 0), 0.23% (CCI = 1), 0.74% (CCI = 2), 3.21% (CCI = 3), 4.76% (CCI = 4), and 0.57% (CCI ≥ 5). Non-OA diagnoses were significantly more frequent in the mortality cohort (16.0% vs 7.6%; P < .001).

CONCLUSION

The risk of mortality was highest in patients aged 80-89, patients of ASA class IV, patients with a CCI score of 4, and patients with a non-OA diagnosis. The overall rate of death was higher in the non-OA cohort compared to the OA cohort.

LEVEL OF EVIDENCE

III.

Does pre-existing morbidity influences risks and benefits of total hip replacement for osteoarthritis: a prospective study of 6682 patients from linked national datasets in England

Total hip arthroplasty (THA) surgery for elderly people with multimorbidity increases the risk of serious health hazards including mortality. Whether such background morbidity reduces the clinical benefit is less clear.

OBJECTIVE

To evaluate how pre-existing health status, using multiple approaches, influences risks of, and quality of life benefits from, THA.

SETTING

Longitudinal record linkage study of a UK sample linking their primary care to their secondary care records.

PARTICIPANTS

A total of 6682 patients were included, based on the recording of the diagnosis of hip osteoarthritis in a national primary care register and the recording of the receipt of THA in a national secondary care register.Data were extracted from the primary care register on background health and morbidity status using five different constructs: Charlson Comorbidity Index, Electronic Frailty Index (eFI) and counts of comorbidity disorders (from list of 17), prescribed medications and number of primary care visits prior to recording of THA.

OUTCOME MEASURES

(1) Postoperative complications and mortality; (2) postoperative hip pain and function using the Oxford Hip Score (OHS) and health-related quality of life using the EuroQoL (EQ)-5D score.

RESULTS

Perioperative complication rate was 3.2% and mortality was 0.9%, both increased with worse preoperative health status although this relationship varied depending on the morbidity construct: the eFI showing the strongest relationship but number of visits having no predictive value. By contrast, the benefits were not reduced in those with worse preoperative health, and improvement in both OHS and EQ-5D was observed in all the morbidity categories.

CONCLUSIONS

Independent of preoperative morbidity, THA leads to similar substantial improvements in quality of life. These are offset by an increase in medical complications in some subgroups of patients with high morbidity, depending on the definition used. For most elderly people, their other health disorders should not be a barrier for THA.

Are We Treating Similar Patients? Hospital Volume and the Difference in Patient Populations for Total Knee Arthroplasty

BACKGROUND

Early findings of superior total knee arthroplasty (TKA) outcomes at high volume centers have been thought to have led to distinct referral patterns. However, the effect of these selective referral processes has not been well assessed. Therefore, this study compared the characteristics of primary TKA patients at high, intermediate, and low volume hospitals.

METHODS

A total of 12,541 primary TKA patients were stratified into risk groups based on age (>65 years), body mass index (>40), and Charlson Comorbidity Index (≥4). Hospitals were classified as low, intermediate, or high volume based on mean annual TKA volumes (<250, 250-499, and >500). Multivariate logistic regression models evaluated the relationship between baseline patient characteristics and hospital volume.

RESULTS

There was a greater percentage of high risk patients at high volume (19%, n = 853) compared to those at intermediate (16%, n = 899) or low volume (17%, n = 444) hospitals (P < .001). Patients with a body mass index >40 were more likely to be treated at high compared to intermediate (odds ratio [OR] 1.4, 95% confidence interval [CI] 1.2-1.6, P < .001) and low volume centers (OR 1.4, 95% CI 1.2-1.7, P < .001). Patients with Charlson Comorbidity Index scores ≥4 were also more likely be treated at high compared to intermediate (OR 1.5, 95% CI 1.3-1.6, P < .001) or low (OR 1.2, 95% CI 1.0-1.4, P = .002) volume centers.

CONCLUSION

This study found that TKA patients at high volume centers have significantly different baseline characteristics compared to those at lower volume centers. This study highlights the importance of considering hospital volume status and the associated disparity in the preoperative risk of patients when comparing primary TKA outcomes between centers.

Effect of Antibiotic-Impregnated Bone Cement in Primary Total Knee Arthroplasty

BACKGROUND

The purpose of this study is to evaluate the effect of commercially available antibiotic-impregnated bone cement (AIBC) on (1) prosthetic joint infections (PJIs) and (2) surgical site infections (SSIs) after primary total knee arthroplasty (TKA).

METHODS

A review of primary TKAs between 2014 and 2017 from an institutional database was conducted. This identified 12,541 cases which were separated into AIBC (n = 4337) and non-AIBC (8,164) cohorts. Medical records were reviewed for PJIs and SSIs (mean 2-year postoperative period). Infection rates between the cohorts were compared with univariate analyses followed by subanalysis of high risk patients (defined as having 2 or more of the following characteristics: >65 years, body mass index >40, or Charlson Comorbidity Index score >3). To control for confounders, multivariate analyses were performed with regression models adjusted for age, gender, body mass index, comorbidities, year, operative times, and lengths of stay.

RESULTS

On univariate analysis, PJI rates were higher in the AIBC cohort (1.0%) compared to the non-AIBC cohort (0.5%, P < .001). Subanalysis of the high risk patients also showed that PJI rates were higher in the AIBC cohort (1.9% vs 0.6%, P < .01). After adjusting for potential confounders, no significant associations between PJIs and AIBC use were found (odds ratio 1.4, 95% confidence interval 0.9-2.3, P = .133). Similarly, no significant differences in SSI rates were observed between the AIBC (2.9%) and non-AIBC cohorts (2.4%, P = .060) and no significant associations between SSIs and AIBC were found with multivariate analysis (odds ratio 1.0, 95% confidence interval CI 0.8-1.3, P = .948).

CONCLUSION

This study found that there was no clinically or statistically significant decrease in infection rates with AIBC in primary TKAs.

Microbiological profile and outcomes of two-stage revision hip arthroplasty

Background

Prosthetic joint infection (PJI) is one of the most challenging cases that confront modern orthopaedics. Two-stage revision, which is the standard of care for PJI, is the preferred mode of treatment for these infections.

Aims and Objectives

To study the microbiological profile of prosthetic joint infections (PJI) in the hip and to assess the efficacy of a two stage revision surgery for PJI. We also aimed to study the sensitivity and specificity of ESR and CRP in the diagnosis of PJI.

Materials and Methods

The microbiological profile, clinical and radiological outcomes of 22 patients who had a two-stage revision for PJI of the hip between 2013 and 2017 were retrospectively analysed. PJI was defined using the criteria provided by the International Consensus Statement on PJI 2013.

Results

Staphylococcus aureus was found to be the most common organism in PJI. Debridement was successful in removing the organism in 74% of PJI. At the time of re-implantation (second stage), six joints grew organisms that were different from that isolated at the index debridement - coagulase-negative staphylococci (3cases) and enterococci (3cases). Other infection parameters for these patients were negative. None of the patients who had two-stage revision surgery had clinical evidence of reinfection or radiological evidence of loosening at a mean of 2-year follow-up. An ESR cut off of >30mm/hr had a sensitivity of 75% and specificity of 88% in predicting PJI. A CRP >10mg/L had a sensitivity of 75% and specificity of 69%. The sensitivity and specificity of using both ESR and CRP cut-offs in the diagnosis of infection were 57% and 94%, respectively. The positive predictive value was 94% and negative predictive value was 56%.

Conclusion

The outcomes of the study justify a two-stage revision arthroplasty for PJI of the hip. The use of ESR and CRP as screening tests for the success of debridement has value - but should be interpreted with caution.

Anaesthetic care of patients undergoing primary hip and knee arthroplasty: consensus recommendations from the International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) based on a systematic review and meta-analysis

BACKGROUND

Evidence-based international expert consensus regarding anaesthetic practice in hip/knee arthroplasty surgery is needed for improved healthcare outcomes.

METHODS

The International Consensus on Anaesthesia-Related Outcomes after Surgery group (ICAROS) systematic review, including randomised controlled and observational studies comparing neuraxial to general anaesthesia regarding major complications, including mortality, cardiac, pulmonary, gastrointestinal, renal, genitourinary, thromboembolic, neurological, infectious, and bleeding complications. Medline, PubMed, Embase, and Cochrane Library including Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, from 1946 to May 17, 2018 were queried. Meta-analysis and Grading of Recommendations Assessment, Development and Evaluation approach was utilised to assess evidence quality and to develop recommendations.

RESULTS

The analysis of 94 studies revealed that neuraxial anaesthesia was associated with lower odds or no difference in virtually all reported complications, except for urinary retention. Excerpt of complications for neuraxial vs general anaesthesia in hip/knee arthroplasty, respectively: mortality odds ratio (OR): 0.67, 95% confidence interval (CI): 0.57-0.80/OR: 0.83, 95% CI: 0.60-1.15; pulmonary OR: 0.65, 95% CI: 0.52-0.80/OR: 0.69, 95% CI: 0.58-0.81; acute renal failure OR: 0.69, 95% CI: 0.59-0.81/OR: 0.73, 95% CI: 0.65-0.82; deep venous thrombosis OR: 0.52, 95% CI: 0.42-0.65/OR: 0.77, 95% CI: 0.64-0.93; infections OR: 0.73, 95% CI: 0.67-0.79/OR: 0.80, 95% CI: 0.76-0.85; and blood transfusion OR: 0.85, 95% CI: 0.82-0.89/OR: 0.84, 95% CI: 0.82-0.87.

CONCLUSIONS

Recommendation: primary neuraxial anaesthesia is preferred for knee arthroplasty, given several positive postoperative outcome benefits; evidence level: low, weak recommendation.

RECOMMENDATION

neuraxial anaesthesia is recommended for hip arthroplasty given associated outcome benefits; evidence level: moderate-low, strong recommendation. Based on current evidence, the consensus group recommends neuraxial over general anaesthesia for hip/knee arthroplasty.

TRIAL REGISTRY NUMBER

PROSPERO CRD42018099935.

Age Is a Risk Factor for Postoperative Complications Following Excisional Laminectomy for Intradural Extramedullary Spinal Tumors

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

The incidence of intradural extramedullary (IDEM) spinal tumors is increasing. Excisional laminectomy for removal and decompression is the standard of care, but complications associated with patient age are unreported in the literature. Our objective is to identify if age is a risk factor for postoperative complications after excisional laminectomy of IDEM spinal tumors.

METHODS

A retrospective analysis was performed on the 2011 to 2014 ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database for patients undergoing excisional laminectomy of IDEM spinal tumors. Age groups were determined by interquartile analysis. Chi-squared tests, t tests, and multivariate logistic regression models were employed to identify independent risk factors. Institutional review board approval was not needed.

RESULTS

A total of 1368 patients met the inclusion criteria for the study. Group 1 (age ≤ 44) contained 372 patients, group 2 (age 45-54) contained 314 patients, group 3 (age 55-66) contained 364 patients, and group 4 (age > 66) contained 318 patients. The univariate analysis showed that mortality and unplanned readmission were highest among patients in group 4 (1.26%, P = .011, and 10.00%, P = .039, respectively). Postoperative wound complications were highest among patients in group 1 (2.15%, P = .009), and postoperative venous thromboembolism and cardiac complications were highest among patients in group 3 (4.4%, P = .007, and 1.10%, P = .032, respectively). Multivariate logistic regression revealed that elderly age was an independent risk factor for postoperative venous thromboembolism (group 3 vs group 1; odds ratio = 6.739, confidence interval = 1.522-29.831, P = .012).

CONCLUSIONS

This analysis revealed that increased age is an independent risk factor for postoperative venous thromboembolism in patients undergoing excisional laminectomy for IDEM spinal tumors.

The Use of Aspirin for Prophylaxis Against Venous Thromboembolism Decreases Mortality Following Primary Total Joint Arthroplasty

BACKGROUND

The use of aspirin as prophylaxis against venous thromboembolism (VTE) following total joint arthroplasty (TJA) has increased in popularity; however, the potential cardioprotective effects of aspirin when administered as VTE prophylaxis remain unknown. The present study investigated the influence of VTE prophylaxis, including aspirin, on mortality following TJA.

METHODS

We retrospectively reviewed 31,133 patients who underwent primary TJA from 2000 to 2017. Patient demographics, body mass index, and comorbidities were obtained from an electronic chart query. Patients were allocated into 2 cohorts on the basis of the VTE prophylaxis administered: aspirin (25.9%, 8,061 patients) and non-aspirin (74.1%, 23,072 patients). Mortality was assessed with use of an institutional mortality database that is updated biannually. Univariate and multivariate regression analyses were performed.

RESULTS

The overall mortality rate was 0.2% and 0.6% at 30 days and 1 year after TJA, respectively. The use of aspirin was independently associated with lower risk of death at both 30 days (odds ratio [OR], 0.39; p = 0.020) and 1 year (OR, 0.51; p = 0.004). Patients in the non-aspirin cohort showed 3 times the risk of death at 30 days compared with the aspirin cohort (0.3% compared with 0.1%; p = 0.004), and twice the risk of death at 1 year (0.7% compared with 0.3%; p < 0.001). At 1 year, the primary cause of death in the non-aspirin group was cardiac-related (46 of 23,072, 0.20%). In the aspirin group, the rate of cardiac-related death was almost 5 times lower (3 of 8,061, 0.04%; p = 0.005). Risk factors for mortality at 1 year included higher age (p < 0.001), male sex (p = 0.020), history of congestive heart failure (p = 0.003), cerebrovascular disease (p < 0.001), malignancy (p < 0.001), and history of prior myocardial infarction (p < 0.001).

CONCLUSIONS

The present study demonstrates that the use of aspirin as prophylaxis against VTE following TJA may reduce the risk of mortality. Given the numerous options available and permitted by the current guidelines, orthopaedic surgeons should be aware of the potential added benefits of aspirin when selecting a VTE-prophylactic agent.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Diabetes Mellitus as a Risk Factor for Acute Postoperative Complications Following Elective Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Diabetes mellitus is a highly prevalent disease in the United States. Adult spinal deformity (ASD) surgery encompasses a wide variety of spinal disorders and is associated with a morbidity rate between 20% and 80%. Considering utilization of spinal surgery will continue to increase, this study investigates the influence of diabetes mellitus on acute postoperative outcomes following elective ASD surgery.

METHODS

The 2010-2014 American College of Surgeon's National Surgical Quality Improvement Program database was queried using Current Procedural Terminology and International Classification of Diseases (9th Revision) diagnosis codes relevant to ASD surgery. Patients were divided into cohorts based on their diabetic status. Bivariate and multivariate logistic regression analyses were employed to identify which 30-day postoperative outcomes patients are at risk for.

RESULTS

A total of 5809 patients met the inclusion criteria for the study of which 4553 (84.2%) patients were nondiabetic, 578 (10.7%) patients had non-insulin-dependent diabetes mellitus (NIDDM), and 275 (5.1%) patients had insulin-dependent diabetes mellitus (IDDM). Diabetes status was significantly associated with length of stay ≥5 days (NIDDM: odds ratio [OR] = 1.27, 95% confidence interval [CI] = 1.02-1.58, P = .034; IDDM: OR = 1.55, 95% CI = 1.15-2.09, P = .004), any complication (NIDDM: OR = 1.26, 95% CI = 1.01-1.58, P = .037), urinary tract infection (NIDDM: OR = 1.87, 95% CI = 1.14-3.05, P = .012), and cardiac complications (IDDM: OR = 4.05, 95% CI = 1.72-9.51, P = .001).

CONCLUSIONS

Given the prevalence of diabetes, surgeons will invariably encounter these patients for ASD surgery. The present study identifies the increased risk NIDDM and IDDM patients experience following ASD surgery. Quantification of this increased risk may improve the selection of appropriate surgical candidates, patient risk stratification, and patient postoperative safety.

Age Stratification of 30-Day Postoperative Outcomes Following Excisional Laminectomy for Extradural Cervical and Thoracic Tumors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To evaluate age as an independent predictive factor for perioperative morbidity and mortality in patients undergoing surgical decompression for metastatic cervical and thoracic spinal tumors using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2011 to 2014.

METHODS

We identified 1673 adult patients undergoing excisional laminectomy of cervical and thoracic extradural tumors. Patients were stratified into quartiles based on age, with Q1 including patients aged 18 to 49 years, Q2 including patients aged 50 to 60 years, Q3 including patients aged 61 to 69 years, and Q4 including patients ≥70 years. Univariate and multivariate regression analyses were performed to examine the association between age and 30-day perioperative morbidity and mortality.

RESULTS

Age was an independent risk factor for 30-day venous thromboembolism (VTE) and reoperation. Patients in Q3 for age had nearly a 4 times increased risk of VTE than patients in Q1 (odds ratio [OR] 3.97; 95% CI 1.91-8.25; P < .001). However, there was no significant difference in VTE between patients in Q4 and Q1 (P = .069). Patients in Q2 (OR 1.99; 95% CI 1.06-3.74; P = .032) and Q4 (OR 2.18; 95% CI 1.06-4.52; P = .036) for age had a 2 times increased risk of reoperation compared with patients in Q1.

CONCLUSIONS

Age was an independent predictive factor for perioperative VTE and reoperation, but there was no clear age-dependent relationship between increasing age and the risk of these perioperative complications.

Predictors for Non-Home Patient Discharge Following Elective Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Adult spinal deformity (ASD) surgery encompasses a wide variety of spinal disorders and is associated with a morbidity rate between 20% and 80%. The utilization of spinal surgery has increased and this trend is expected to continue. To effectively deal with an increasing patient volume, identifying variables associated with patient discharge destination can expedite placement and reduce length of stay.

METHODS

The 2013-2014 American College of Surgeons National Surgical Quality Improvement Program database was queried using Current Procedural Terminology and International Classification of Diseases, Ninth Revision diagnosis codes relevant to ASD. Patients were divided based on discharge destination. Bivariate and multivariate logistic regression analyses were employed to identify predictors for patient discharge destination and hospital length of stay.

RESULTS

A total of 4552 patients met inclusion criteria, of which 1102 (24.2%) had non-home discharge. Multivariate regression revealed total relative value unit (odds ratio [OR] = 1.01, 95% confidence interval [CI] = 1.00-1.01); female sex (OR = 1.54, 95% CI = 1.32-1.81); American Indian, Alaska Native, Asian, Native Hawaiian, or Pacific Islander versus black race (OR = 0.52, 95% CI = 0.35-0.78, P = .002); age ≥65 years (OR = 3.72, 95% CI = 3.19-4.35); obesity (OR = 1.18, 95% CI = 1.01-1.38, P = .034); partially/totally functionally dependent (OR = 2.11, 95% CI = 1.49-2.99); osteotomy (OR = 1.42, 95% CI = 1.12-1.80, P = .004) pelvis fixation (OR = 2.38, 95% CI = 1.82-3.11); operation time ≥4 hours (OR = 1.74, 95% CI = 1.47-2.05); recent weight loss (OR = 7.66, 95% CI = 1.52-38.65; P = .014); and American Society of Anesthesiologists class ≥3 (OR = 1.80, 95% CI = 1.53-2.11) as predictors of non-home discharge. P values were <.001 unless otherwise noted. Additionally, multivariate regression found non-home discharge to be a significant variable in prolonged length of stay.

CONCLUSIONS

The authors suggest these results can be used to inform patients preoperatively of expected discharge destination, anticipate patient discharge needs postoperatively, and reduce health care costs and morbidity associated with prolonged LOS.

Nutritional Insufficiency as a Predictor for Adverse Outcomes in Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective analysis of prospectively collected data.

OBJECTIVE

The effect of malnutrition on outcomes after general surgery has been well reported in the literature. However, there is a paucity of data on the effect of malnutrition on postoperative complications during adult deformity surgery. The study attempts to explore and quantify the association between hypoalbuminemia and postoperative complications.

METHODS

A retrospective cohort analysis was performed on the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database from 2010 to 2014. Patients (≥18 years of age) from the NSQIP database undergoing adult deformity surgery were separated into cohorts based serum albumin (<3.5 or >3.5 g/dL). Chi-square and multivariate logistic regression models were used to identify independent risk factors.

RESULTS

A total of 2236 patients met the inclusion criteria for the study, of which 2044 (91.4%) patients were nutritionally sufficient while 192 (8.6%) patients were nutritionally insufficient. Multivariate logistic regressions revealed nutritional insufficiency as a risk factors for mortality (odds ratio [OR] = 15.67, 95% confidence interval [CI] = 6.01-40.84, P < .0001), length of stay ≥5 days (OR = 2.22, 95% CI = 1.61-3.06, P < .0001), any complications (OR = 1.82, 95% CI = 1.31-2.51, P < .0001), pulmonary complications (OR = 2.29, 95% CI = 1.29-4.06, P = .005), renal complications (OR = 2.71, 95% CI = 1.05-7.00, P = .039), and intra-/postoperative red blood cell transfusion (OR = 1.52, 95% CI = 1.08-2.12, P = .015).

CONCLUSIONS

This study demonstrates that preoperative hypoalbuminemia is a significant and independent risk factor for postoperative complications, 30-day mortality, and increased length of hospital in patients undergoing adult deformity surgery surgery. Nutritional status is a modifiable risk factor that can potentially improve surgical outcomes after adult deformity surgery.

The Influence of Patient Gender on Morbidity Following Total Hip or Total Knee Arthroplasty

BACKGROUND

Little research has focused on the influence of gender on postoperative morbidity following total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study aimed to compare operative time, length of stay, 30-day complications, and readmissions based on patient gender.

METHODS

The prospectively collected National Surgical Quality Improvement Program registry from 2005 to 2014 was queried to identify primary elective THA and TKA patients. Multivariate regression was used to compare the rates of 30-day adverse events, rates of readmission, operative time, and postoperative length of stay between men and women. Multivariate analyses were controlled for baseline patient characteristics and procedure type.

RESULTS

A total of 173,777 patients were included (63.5% TKA and 36.5% THA). Male gender increased the risk of multiple adverse events, including death (relative risk [RR] 1.1, P < .001), surgical site infection (RR 1.2, P < .001), sepsis (RR 1.4, P < .001), cardiac arrest (RR 1.8, P < .001), and return to the operating room (RR 1.3, P < .001). Men had decreased overall adverse events (RR 0.8, P < .001) secondary to a lower risk of urinary tract infection (RR 0.5, P < .001) and blood transfusion (RR 0.7, P < .001), which were prevalent adverse events. Men had an increased risk of 30-day readmission (RR 1.2, P < .001), slightly increased operative time (+6 minutes, P < .001), and slightly decreased length of stay (-0.2 days, P < .001).

CONCLUSION

Men had increased risk of multiple individual adverse events including death, surgical site infection, cardiac arrest, return to the operating room, and readmission. Conversely, women had increased risk of urinary tract infection and blood transfusion.

Predictors for Patient Discharge Destination After Elective Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective study of prospectively collected data.

OBJECTIVE

To identify risk factors for nonhome patient discharge after elective anterior cervical discectomy and fusion (ACDF).

SUMMARY OF BACKGROUND DATA

ACDF is one of the most performed spinal procedures and this is expected to increase in the coming years. To effectively deal with an increasing patient volume, identifying variables associated with patient discharge destination can expedite placement applications and subsequently reduce hospital length of stay.

METHODS

The 2011 to 2014 ACS-NSQIP database was queried using Current Procedural Terminology (CPT) codes 22551 or 22554. Patients were divided into two cohorts based on discharge destination. Bivariate and multivariate logistic regression analyses were employed to identify predictors for patient discharge destination and extended hospital length of stay.

RESULTS

A total of 14,602 patients met the inclusion criteria for the study of which 498 (3.4%) had nonhome discharge. Multivariate logistic regression found that Hispanic versus Black race/ethnicity (odds ratio, OR =0.21, 0.05-0.91, P =0.037), American Indian or Alaska Native, Asian, Native Hawaiian or Pacific Islander versus Black race/ethnicity (OR = 0.52, 0.34-0.80, p-value = 0.003), White versus Black race/ethnicity (OR = 0.55, 0.42-0.71), elderly age ≥65 years (OR = 3.32, 2.72-4.06), obesity (OR = 0.77, 0.63-0.93, P = 0.008), diabetes (OR = 1.32, 1.06-1.65, P = 0.013), independent versus partially/totally dependent functional status (OR = 0.11, 0.08-0.15), operation time ≥4 hours (OR = 2.46, 1.87-3.25), cardiac comorbidity (OR = 1.38, 1.10-1.72, P = 0.005), and ASA Class ≥3 (OR = 2.57, 2.05-3.20) were predictive factors in patient discharge to a facility other than home. In addition, multivariate logistic regression analysis also found nonhome discharge to be the most predictive variable in prolonged hospital length of stay.

CONCLUSION

Several predictive factors were identified in patient discharge to a facility other than home, many being preoperative variables. Identification of these factors can expedite patient discharge applications and potentially can reduce hospital stay, thereby reducing the risk of hospital acquired conditions and minimizing health care costs.

LEVEL OF EVIDENCE

3.

Analysis of Risk Factors for Major Complications Following Elective Posterior Lumbar Fusion

STUDY DESIGN

Retrospective study of prospectively collected data.

OBJECTIVE

To identify risk factors for the development of any major complication after elective posterior lumbar fusion (PLF).

SUMMARY OF BACKGROUND DATA

PLF is one of the most performed fusion techniques with utilization rates increasing by 356% between 1993 and 2001. Surgical and anesthetic advances have made the option of surgery more accessible for elderly patients with a larger comorbidity burden. Identifying risk factors for the development of major complications after elective PLF is important for patient risk stratification and patient safety efforts.

METHODS

The 2011 to 2014 American College of Surgeon's National Surgical Quality Improvement Program database was queried using Current Procedural Terminology codes 22612, 22630, and 22633. Patients were divided into two cohorts based on the development of any major complication. Bivariate and multivariate logistic regression analyses were employed to identify predictors for the development of ≥ 1, ≥ 2, and ≥ 3 major complications.

RESULTS

A total of 7761 patients met the inclusion criteria for the study of which, 2055 (26.5%) patients developed one major complication, 249 (3.2%) patients developed two major complications, and 151 (1.9%) patients developed three major complications. The most common complication was intra/postoperative red blood cell transfusion (23.2%). Three multivariate logistic regression models were employed to identify factors associated with ≥ 1, ≥ 2, and ≥ 3 major complications. Patient variables present across all three models were osteotomy, pelvic fixation, operation time ≥4 hours, bleeding disorder, and American Society of Anesthesiology Class ≥ 3.

CONCLUSION

Several risk factors were identified for the development of major complications after elective PLF. Identification of these factors can improve the selection of appropriate surgical candidates, patient risk stratification, and patient postoperative safety.

LEVEL OF EVIDENCE

3.

Presentation and management of symptomatic central bone cement embolization

BACKGROUND CONTEXT

With more cement augmentation procedures done, the occurrence of serious complications is also expected to rise. Symptomatic central cement embolization is a rare but very serious complication. Moreover, the pathophysiology and treatment of intrathoracic cement embolism remain controversial.

PURPOSE

In this case series, we are trying to identify various presentations and suggest our emergent management scheme for symptomatic central cement embolization.

PATIENT SAMPLE

Retrospective case series of nine patients with symptomatic central cement embolism identified after vertebroplasty with 24 months of follow-up. Level IV.

OUTCOME MEASURES

The degree of dyspnea measured by the New York Heart Association (NYHA) score and/or death related to cement embolism induced cardio/respiratory failure at the final follow-up at 24 months.

METHODS

The nine patients, eight females, and one male had a mean age of 70.25 years (range 65-78 years) and were operated between January 2004 and December 2014. They had percutaneous vertebroplasty for osteoporotic non-traumatic and malignant vertebral collapse of dorsal and lumbar vertebrae. Post-vertebroplasty dyspnea and stitching chest pain were striking in the nine patients. After exclusion of cardiac ischemia and medical pulmonary causes for dyspnea, we identified radiopaque lesions on the chest X-ray. Further echocardiography and high-resolution chest CT were performed for optimal localization. Emergent heart surgery was performed in two patients: interventional therapy was conducted in one patient, while the remaining six patients were conservatively treated by anticoagulation. The management decision was taken in the setting of an interdisciplinary meeting depending on localization, fragmentation, and clinical status.

RESULTS

All patients of this series showed gradual improvement and an uneventful hospital stay. During our 24-month follow-up phase, eight patients showed no subsequent cardiological and/or respiratory symptoms (NYHA I). However, one mortality due to advanced malignancy occurred. Preoperative anemia was the only common intersecting preoperative parameter among these nine patients.

CONCLUSIONS

After cement augmentation, close clinical monitoring is mandatory. A chest CT is pivotal in determining the interdisciplinary management approach in view of the availability of necessary expertise, facilities and the location of the cement emboli whether accessible by cardiac or vascular surgical means. The clinical presentation and its timing may vary and the patient may be seen subsequently by other health care providers obligating a wide-spread awareness for this serious entity among health care providers for this age group as spine surgeons, family and emergency room doctors, and institutional or home-care nurses. Most symptomatic central cement emboli may be treated conservatively.

Efficacy evaluation of a protocol for safe hip surgery (total hip arthroplasty)

Objective

To propose a multidisciplinary protocol to standardize the care of patients undergoing total hip arthroplasty (THA) and evaluate it effectiveness after implementation.

Methods

Retrospective evaluation of 95 consecutive patients undergoing THA divided into two groups, one group of 47 patients operated before the protocol implementation and 48 after.

Results

Assessing the re-admission rate, among 47 patients evaluated prior to implementation of the protocol, seven (14.9%) were re-admitted, and when observing the 48 patients evaluated after implementation, one (2.1%) was re-admitted, showing statistical significance (p < 0.05). The chance of re-admission before the protocol was eight times the chance of hospitalization after implementation (95% CI: 1.01 to 377.7). By comparing the clinical complications among the groups, it was observed that there was a lower rate of complications following implementation of the protocol (p = 0.006).

Conclusion

The introduction of a multidisciplinary protocol to standardize the management of patients undergoing THA decreased the rates of rehospitalization and clinical complications after the procedure.

Is Preoperative Patient-Reported Health Status Associated with Mortality after Total Hip Replacement?

The influence of comorbidities and worse physical status on mortality following total hip replacement (THR) leads to the idea that patient-reported health status may also be a predictor of mortality. The aim of this study was to investigate the relationship between patient-reported health status before THR and the risk of dying up to 5 years post-operatively. For these analyses, we used register data on 42,862 THR patients with primary hip osteoarthritis operated between 2008 and 2012. The relative survival ratio was calculated by dividing the observed survival in the patient group by age- and sex-adjusted expected survival of the general population. Pre-operative responses to the five EQ-5D-3L (EuroQol Group) dimensions along with age, sex, education status, year of surgery, and hospital type were used as independent variables. Results shown that, as a group, THR patients had a better survival than the general population. Broken down by the five EQ-5D-3L dimensions we observed differentiated survival patters. For all dimensions, those reporting extreme problems had higher mortality than those reporting moderate or no problems. In conclusion, worse health status according to the EQ-5-3L before THR is associated with higher mortality up to five years after surgery. EQ-5D-3L responses may be useful in a multifactorial individualized risk assessment before THR.

Elderly Age as a Risk Factor for 30-Day Postoperative Outcomes Following Elective Anterior Cervical Discectomy and Fusion

STUDY DESIGN

Retrospective analysis of prospectively collected data.

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) is one of the most commonly performed spinal procedures. Considering the high success and low complications rate of ACDF and high prevalence of age-related degeneration of the cervical spine, the rates of ACDF are expected to continually rise. The objective is to identify the association between patient age and 30-day postoperative outcomes following elective ACDF.

METHODS

The 2010-2014 ACS-NSQIP database was queried using Current Procedural Terminology (CPT) codes 22551 or 22554. Patients were divided into age quartiles (18-45, 46-52, 53-60, and ≥61 years). Bivariate and multivariate logistic regression analyses were employed to quantify the increased risk of 30-day postoperative complications in the elderly patient population.

RESULTS

A total of 20 563 patients met the inclusion criteria for the study. The analyses found quartile 4 had an increased odds of length of stay (LOS) ≥5 days (odds ratio [OR] = 2.05, confidence interval [CI ] = 1.62-2.60), pulmonary complications (OR = 3.25, CI = 1.81-5.84), urinary tract infections (UTI) (OR = 2.25, 1.04-4.87, P = .038), cardiac complication (OR = 6.01, CI = 1.36-26.62, P = .018), and sepsis (OR = 4.38, CI = 1.30-14.70, P = .017). Quartiles 2 and 4 had an increased odds of venous thromboembolism (OR = 3.13, CI = 1.14-8.56, P = .026; OR = 3.83, CI = 1.44-10.20, P = .007). Quartiles 3 and 4 experienced an increased odds of unplanned readmission (OR = 1.44, CI = 1.01-2.05, P = .045; OR = 1.88, CI = 1.33-2.66). All P values are <.001 unless otherwise noted.

CONCLUSION

Elderly patients experienced an increased odds of LOS ≥5 days, pulmonary complications, cardiac compilations, venous thromboembolism, UTI, sepsis, and unplanned readmission. Identification of these factors can improve the selection of appropriate surgical candidates and postoperative safety.

In-Hospital Mortality in Patients With Periprosthetic Joint Infection

BACKGROUND

While periprosthetic joint infection (PJI) has a huge impact on patient function and health, only a few studies have investigated its impact on mortality. The purpose of this large-scale study was to (1) determine the rate and trends of in-hospital mortality for PJI and (2) compare the in-hospital mortality rate of patients with PJI and those undergoing revision arthroplasty for aseptic failure and patients undergoing other nonorthopedic major surgical procedures.

METHODS

Data from the Nationwide Inpatient Sample from 2002 to 2010 were analyzed to determine the risk of in-hospital mortality for PJI patients compared with aseptic revision arthroplasty. The Elixhauser comorbidity index was used to obtain patient comorbidities. Multiple logistic regression analyses were used to examine whether PJI and other patient-related factors were associated with mortality.

RESULTS

PJI was associated with an increased risk (odds ratio, 2.05; P < .0001) of in-hospital mortality (0.77%) compared with aseptic revisions (0.38%). The in-hospital mortality rate of revision total hip arthroplasties with PJI was higher than those for interventional coronary procedures (1.22%; 95% confidence interval [CI], 1.20-1.24), cholecystectomy (1.13%; 95% CI, 1.11-1.15), kidney transplant (0.70%; 95% CI, 0.61-0.79), and carotid surgery (0.89%; 95% CI, 0.86-0.93).

CONCLUSION

Patients undergoing treatment for PJI have a 2-fold increase in in-hospital mortality for each surgical admission compared to aseptic revisions. Considering that PJI cases often have multiple admissions and that this analysis is by surgical admission, the risk of mortality will accumulate for every additional surgery. Surgeons should be cognizant of the potentially fatal outcome of PJI and the importance of infection control to reduce the risk of mortality.

[Incidence of hip and knee prosthetic infections in a specialized center of Mexico City]

BACKGROUND

Hip and knee prosthetic replacements have proven to be the most appropriate treatment in the joints that do not benefit from medical or arthroscopic interventions; however, infections are the most feared complication. It is recommended that the incidence of infection should not exceed 2%.

MATERIAL AND METHODS

This was an observational, prospective, longitudinal and observational study conducted in patients fitted with a prosthetic joint from August 2011 to July 2012. Patients were followed up pre and post-surgery for one year to identify a prosthetic infection, diagnosed using international parameters. We calculated the incidence of prosthetic infection, as well as the incidence density.

RESULTS

A total of 339 patients (179 hip and 160 knee) were included. Variations in the time of pre-operative antibiotics' administration were observed. Six prosthetic infections were identified with an incidence rate of 1.79/339 arthroplasties, 2.2/179 hip procedures, and 1.25/160 knee arthroplasties. An incidence density of 0.02/year for hip arthroplasties and 0.11/year for knee procedures was identified. There were 4 infections of hip and 2 of knee. Five infections were acute and one chronic. The isolated microorganisms were E. faecalis, S. epidermidis (2), S. mitis, S. aureus and P. stomatis.

CONCLUSIONS

The incidence of prosthetic joint infection in the first year of follow-up at our centre is within the recommended parameters. Surgical techniques and organizational practices influence the results.

Evaluation of three co-morbidity measures to predict mortality in patients undergoing total joint arthroplasty

OBJECTIVE

To evaluate the 90 days and 1 year mortality predictive ability of the RxRisk-V, Charlson, and Elixhauser co-morbidity measures in total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients.

METHOD

A retrospective study of 11,848 THAs and 18,972 TKAs (2001-2002) was conducted. Death within 90 days and 1 year of the surgery were the main endpoints. Co-morbidity measures were calculated using either medication or hospitalisation history. Logistic regression models were employed and discrimination and calibration were assessed. Specifically, models with unweighted and weighted measure scores, models with the specific conditions, and a model combining conditions identified by all measures were assessed.

RESULTS

In THAs, the best performing prediction models included co-morbidities from all three measures (90 days: c = 0.84, P = 0.284, 1 year: c = 0.79, P = 0.158). Individually, the model with Charlson conditions performed best at 90 days mortality (c = 0.80, P = 0.777) and the Charlson and Elixhauser performed similarly at 1 year (both c = 0.77, P > 0.05). In TKAs, the best performing prediction model included co-morbidities from all measures (90 days: c = 0.82, P = 0.349, 1 year: c = 0.78, P = 0.873). Individually, the model with Elixhauser conditions performed best with 90 days mortality (c = 0.79, P = 0.435) and all performed similarly at 1 year (c = 0.74-0.75, all P > 0.05).

CONCLUSIONS

A combined model with co-morbidities identified by the Elixhauser, Charlson, and RxRisk-V was the best mortality prediction model. The RxRisk-V did not perform as well as the others. Because of the Elixhauser and Charlson's similar performance we suggest basing the choice of measurement use on factors such as the need of specific conditions and modelling limitations.

The Effect of Diabetes Mellitus on Total Joint Arthroplasty Outcomes

Diabetes has negative effects on the outcomes of total joint arthroplasty, including increased numbers of complications, decreased function, early revision, and higher costs. The prevalence of diabetes is increasing rapidly worldwide; therefore, the orthopaedic surgeon should have an understanding of how diabetes affects surgical outcomes.

Renal and Gastrointestinal Considerations in Patients Undergoing Elective Orthopaedic Surgery

To minimize perioperative complications after orthopaedic procedures, patients may undergo medical optimization, which includes an assessment of their renal function and gastrointestinal (GI) system. The GI and renal systems are complex, and their proper optimization in the preoperative period can influence the success of any procedure. Several factors can prevent complications and reduce morbidity, mortality, and the cost of care, including a thorough evaluation and screening, with particular emphasis on anemia and its renal and GI causes; management of medications that are metabolized by the liver and excreted by the kidneys; and careful attention to the patient's nutritional status.

Early postoperative mortality after simultaneous or staged bilateral primary total hip arthroplasty: an observational register study from the Swedish Hip Arthroplasty Register

BACKGROUND

Approximately a fifth of all total hip arthroplasty (THA) patients suffers from bilateral osteoarthritis of the hip. It is unclear whether mortality risks differ between simultaneous bilateral THA and staged bilateral THA. We investigated mortality after simultaneous THA compared with staged bilateral THA in the largest cohort hitherto reported.

METHODS

The 42,238 patients reported to have received bilateral primary THA from 1992 to 2012 in the Swedish Hip Arthroplasty Register were included. Tumours and fractures as underlying diagnoses were excluded. The time interval between the first and second THA was divided into four categories or treated as a continuous variable. Unadjusted survival was calculated according to Kaplan-Meier and adjusted Cox regression models were fitted in order to calculate crude and adjusted hazard ratios (HR) for the risk of death within different time frames.

RESULTS

Patients selected for simultaneous bilateral surgery were younger, more often male, and had lower ASA (American Society of Anesthesiologists) class than patients receiving staged procedures. The adjusted 90-day mortality after the second procedure did not differ between the four investigated groups (simultaneous bilateral [HR 1.3, CI 0.5-3.3], surgeries within 6 months [HR 1.1, CI 0.6-2.0], surgeries between 7 and 12 months [HR 0.7, CI 0.4-1.2], with second surgery after >12 months as the reference group). For patients older than 75 years, men, patients with ASA class 3 or above, and for patients with rheumatoid arthritis (RA) the 90-day mortality was increased. The unadjusted risk of implant revision of any hip was slightly higher for patients with simultaneous bilateral THA compared to those with staged procedure within one year, but after adjustment for age, gender, diagnosis and implant fixation these differences were no longer statistically significant.

CONCLUSION

There were no clinically relevant differences in early postoperative mortality between simultaneous and staged bilateral surgery in healthy patients. Advanced age, RA, a high ASA class and male sex increased the risk of death within 90 days. There may be an issue with enhanced risk of implant revision in patients with simultaneous bilateral THA that needs to be explored further.

Morbidity and mortality in the thirty-day period following total hip arthroplasty: risk factors and incidence

The study sought to ascertain the incidence rates and risk factors for 30-day post-operative complications after primary total hip arthroplasty (THA). Complications were categorized as systemic or local and subcategorized as major or minor. There were 17,640 individuals who received primary THA identified from the 2006-2011 ACS NSQIP. The mortality rate was 0.35% and complications occurred in 4.9%. Age groups ≥ 80 years (P <0.001) and 70-79 years old (P = 0.003), and renal insufficiency (P = 0.02) best predicted mortality. Age ≥80 years (P <0.001) and cardiac disease (P = 0.01) were the strongest predictors of developing any postoperative complication. Morbid obesity (P <0.001) and operative time > 141 minutes (P <0.001) were strongly associated with the development of major local complications.

Mortality following hip arthroplasty--inappropriate use of National Joint Registry (NJR) data

Mortality following hip arthroplasty is affected by a large number of confounding variables each of which must be considered to enable valid interpretation. Relevant variables available from the 2011 NJR data set were included in the Cox model. Mortality rates in hip arthroplasty patients were lower than in the age-matched population across all hip types. Age at surgery, ASA grade, diagnosis, gender, provider type, hip type and lead surgeon grade all had a significant effect on mortality. Schemper's statistic showed that only 18.98% of the variation in mortality was explained by the variables available in the NJR data set. It is inappropriate to use NJR data to study an outcome affected by a multitude of confounding variables when these cannot be adequately accounted for in the available data set.

Mortality after total hip replacement surgery: A systematic review

Total hip replacement causes a short-term increase in the risk of mortality. It is important to quantify this and to identify modifiable risk factors so that the risk of post-operative mortality can be minimised. We performed a systematic review and critical evaluation of the current literature on the topic. We identified 32 studies published over the last 10 years which provide either 30-day or 90-day mortality data. We estimate the pooled incidence of mortality during the first 30 and 90 days following hip replacement to be 0.30% (95% CI 0.22 to 0.38) and 0.65% (95% CI 0.50 to 0.81), respectively. We found strong evidence of a temporal trend towards reducing mortality rates despite increasingly co-morbid patients. The risk factors for early mortality most commonly identified are increasing age, male gender and co-morbid conditions, particularly cardiovascular disease. Cardiovascular complications appear to have overtaken fatal pulmonary emboli as the leading cause of death after hip replacement.

Cite this article: Bone Joint Res 2014;3:175–82.

Higher Charlson Comorbidity Index Scores are associated with readmission after orthopaedic surgery

BACKGROUND

The Charlson Comorbidity Index (CCI) originally was developed to predict mortality within 1 year of hospital admission in patients without trauma. As it includes factors associated with medical and surgical complexities, it also may be useful as a predictive tool for hospital readmission after orthopaedic surgery, but to our knowledge, this has not been studied.

QUESTIONS/PURPOSES

We asked whether an increased score on the CCI was associated with (1) readmission, (2) an increased risk of surgical site infection or other adverse events, (3) transfusion risk, or (4) mortality after orthopaedic surgery.

METHODS

A total of 30,129 orthopaedic surgeries performed between 2008 and 2011 without any orthopaedic surgery in the preceding 30 days were analyzed. International Classification of Diseases, 9(th) Revision codes were used to identify diagnoses, procedures, surgery-related adverse events, surgical site infection, and comorbidities as listed in the updated and reweighted CCI. A total of 913 patients (3.0%) were readmitted within 30 days after discharge; in 393 (1.4%) patients adverse events occurred; 417 patients (1.4%) had a surgical site infection develop; 211 (0.7%) needed transfusions, and 56 (0.2%) died within 30 days after surgery. Ordinary least squares regression analyses were used to determine whether the CCI was associated with these outcomes.

RESULTS

The CCI accounted for 10% of the variation in readmissions. Every point increase in CCI score added an additional 0.45% risk in readmission for patients undergoing arthroplasty, 0.63% for patients undergoing trauma surgery, and 0.9% risk for patients undergoing spine surgery (all p < 0.01). The CCI was not associated with surgical site infection or other adverse events, but accounted for 8% of the variation in transfusion rate and 10% of the variation in mortality within 30 days of surgery.

CONCLUSIONS

The CCI can be used to estimate the risk of readmission after arthroplasty, hand and upper extremity surgery, spine surgery, and trauma surgery. It also can be used to estimate the risk of transfusion after arthroplasty, spine, trauma, and oncologic orthopaedic surgery and the risk of mortality after shoulder, trauma, and oncologic orthopaedic surgery.

LEVEL OF EVIDENCE

Level IV, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.

Incidence and mortality of perioperative cardiac events in cervical spine surgery

STUDY DESIGN

Retrospective database analysis.

OBJECTIVE

To determine the national incidence, mortality, and risk factors for perioperative cardiac complications associated with cervical spine surgery in the United States.

SUMMARY OF BACKGROUND DATA

Perioperative myocardial infarctions and cardiac failure are leading causes of mortality in noncardiac surgery. The incidence of these complications has not been reported in cervical spine surgery.

METHODS

Data from the Nationwide Inpatient Sample was obtained from 2002-2009. Patients undergoing anterior or posterior cervical fusion and posterior cervical decompression without fusion for degenerative etiologies were identified. Only elective admissions were included. Incidences of cardiac complications were identified and patient demographics, hospital costs, length of stay, and mortality were compared for each group. Logistic regression was used to identify independent predictors of cardiac complications.

RESULTS

A total of 214,900 elective cervical spine procedures were identified in the United States from 2002-2009. Overall, there were 4.0 cardiac events per 1000 cases. For individual procedures, the incidence was 11.6 per 1000 posterior cervical fusions, 5.2 per 1000 posterior cervical decompressions, and 3.2 per 1000 anterior cervical fusions. Patients with cardiac events were statistically older with greater comorbidities (P < 0.0005). Across all cohorts, length of stay increased an additional 4.5 days, hospital costs increased $13,435, and mortality increased from 0.8 to 65.3 deaths per 1000 cases in the presence of a cardiac event (P < 0.0005). Logistic regression analysis demonstrated that independent predictors for cardiac events included age 65 years or more, multilevel fusions, acute blood-loss anemia, congestive heart failure, fluid/electrolyte disorders, and pulmonary circulation disorders.

CONCLUSION

Our results demonstrate an overall incidence of 4.0 cardiac events per 1000 cervical spine surgical procedures. Older patients with greater comorbid risk factors, particularly cardiovascular diseases, were at significantly increased risk for cardiac complications. Due to the large impact cardiac events have on health care utilization and mortality, we recommend thorough risk stratification for older patients undergoing elective cervical spine procedures.

LEVEL OF EVIDENCE

3.