The international normalised ratio predicts perioperative complications in revision total hip arthroplasty

Preoperative demographics and laboratory markers may be associated with early dislocation after total hip arthroplasty

PURPOSE

The purpose of this study was to identify modifiable medical comorbidities, laboratory markers and flaws in perioperative management that increase the risk of acute dislocation in total hip arthroplasty (THA) patients.

METHODS

All THA with primary indications of osteoarthritis from 2007 to 2020 were queried from the National Surgical Quality Improvement Program (NSQIP) database. Demographic data, preoperative laboratory values, recorded past medical history, operative details as well as outcome and complication information were collected. The study population was divided into two cohorts: non-dislocation and dislocation patients. Statistics were performed to compare the characteristics of both cohorts and to identify risk factors for prosthetic dislocation (α < 0.05).

RESULTS

275,107 patients underwent primary THA in 2007 to 2020, of which 1,258 (0.5%) patients experienced a prosthetic hip dislocation. Demographics between non-dislocation and dislocation cohorts varied significantly in that dislocation patients were more likely to be female, older, with lower body mass index and a more extensive past medical history (all p < 0.05). Moreover, hypoalbuminemia and moderate/severe anemia were associated with increased risk of dislocation in a multivariate model (all p < 0.05). Finally, use of general anesthesia, longer operative time, and longer length of hospital stay correlated with greater risk of prosthetic dislocation (all p < 0.05).

CONCLUSIONS

Elderly female patients and patients with certain abnormal preoperative laboratory values are at risk for sustaining acute dislocations after index THA. Careful interdisciplinary planning and medical optimization should be considered in high-risk patients as dislocations significantly increase the risk of sepsis, cerebral vascular accident, and blood transfusions on readmission.

Alkaline Phosphatase is an Independent Risk Factor for Periprosthetic Fractures in Total Joint Arthroplasty

BACKGROUND

Serum alkaline phosphatase (ALP) is a biomarker for chronic low-grade inflammation along with hepatobiliary and bone disorders. High abnormal ALP levels in blood have been associated with metabolic bone disease and high bone turnover.

METHODS

All primary total hip and knee arthroplasties from 2005 to 2019 were queried from the National Surgical Quality Improvement Program database. Patients with available serum ALP levels were included and stratified to low (<44 IU/L), normal (44 to 147 IU/L), and high (>147 IU/L). A risk-adjusted multivariate logistic regression was used to analyze ALP as an independent risk factor of complications.

RESULTS

The analysis included 324,592 patients, consisting of 11,427 low ALP, 305,977 normal ALP, and 7,188 high preoperative ALP level patients undergoing total joint arthroplasty. Adjusted multivariate logistic regression analysis showed high ALP level patients had an overall increased risk of readmission within 30 days of surgery compared with the control group (odds ratio [OR], 1.69; P < 0.01). High ALP patients also had an increased risk of postoperative periprosthetic fracture (OR, 1.6), postoperative wound infection (OR, 1.81), pneumonia (OR, 2.24), renal insufficiency (OR, 2.39), cerebrovascular disease (OR, 2.2), postoperative bleeding requiring transfusion (OR, 1.83), sepsis (OR, 2.35), length of stay > 2 days (OR, 1.47), Clostridium difficile infection (OR, 2.07), and discharge to a rehab facility (OR, 1.41) (all P < 0.05). A low ALP level was also associated with increased postoperative bleeding transfusion risk (OR, 1.12; P < 0.01) and developing a deep vein thrombosis (OR, 1.25; P = 0.03).

CONCLUSION

Abnormal serum ALP levels in patients undergoing primary total joint arthroplasty are associated with increased postoperative periprosthetic fracture risk and medical complications requiring increased length of stay and discharge to a rehabilitation facility.

Preoperative Malnutrition and Metabolic Markers May Predict Periprosthetic Fractures in Total Hip Arthroplasty

Background

Periprosthetic fractures are a devastating complication of total hip arthroplasty (THA) and are associated with significantly higher mortality rates in the postoperative period. Given the strain that periprosthetic fractures place on the patient as well as the healthcare system, identifying and optimizing medical comorbidities is essential in reducing complications and improving outcomes.

Methods

All THA with primary indications of osteoarthritis from 2007 to 2020 were queried from the National Surgical Quality Improvement Program database. Demographic data, preoperative laboratory values, medical comorbidities, hospital course, and acute complications were collected and compared between patients with and without readmission for a periprosthetic fracture. A multivariate logistic regression analysis was performed to determine associated independent risk factors for periprosthetic fractures after index THA.

Results

The analysis included 275,107 patients, of which 2539 patients were readmitted for periprosthetic fractures. Patients with postoperative fractures were more likely to be older (>65 years), females, BMI >40, and increased medical comorbidities. Preoperative hypoalbuminemia, hyponatremia, and abnormal estimated glomerular filtration rates were independent risk factors for sustaining a periprosthetic fracture and readmission within 30 days. Modifiable patient-related factors of concurrent smoking and chronic steroid use at the time of index THA were also independent risk factors for periprosthetic fractures. Inpatient metrics of longer length of stay, operative time, and discharge to rehab predicted postarthroplasty fracture risk. Readmitted fracture patients subsequently had increased risks of developing a surgical site infection, urinary tract infection, and requiring blood transfusions.

Conclusions

Patients with hypoalbuminemia, hyponatremia, and abnormal estimated glomerular filtration rate are at increased risk for sustaining periprosthetic fractures after THA. Preoperative optimization with close monitoring of metabolic markers and modifiable risk factors may help not only prevent acute periprosthetic fractures but also associated infection and bleeding risk with fracture readmission.

Abnormal Preoperative Platelet Count May Predict Postoperative Complications Following Shoulder Arthroplasty

Background

The purpose of this study is to investigate the association between preoperative platelet counts and postoperative complication rates within 30 days of total shoulder arthroplasty (TSA).

Methods

The American College of Surgeons National Surgical Quality Improvement database was queried for all patients who underwent TSA between 2015 and 2019. The study population was then divided into 5 groups based on their preoperative platelet count: <100k (moderate-to-severe thrombocytopenia), 100-150k (mild thrombocytopenia), 150-200k (low-normal preoperative platelet count), 200-450k (normal, reference cohort), and >450k (thrombocytosis). Postoperative complications within 30 days of the TSA were collected. Multivariate logistic regression analysis was conducted to investigate the relationship between preoperative platelet counts and postoperative complications.

Results

A total of 19,721 patients undergoing TSA between 2015 and 2019 were included in this study. One hundred fifty-five patients (0.8%) had moderate-to-severe thrombocytopenia, 982 (5.0%) had mild thrombocytopenia, 3945 (20.0%) had a low-normal preoperative platelet count, 14,386 (72.9%) had a normal preoperative platelet count, and 253 (1.3%) had thrombocytosis. An increasing rate of overall complications was observed as the severity of thrombocytopenia progressed from low-normal (6.4%) to mild thrombocytopenia (10.2%) and to moderate-to-severe thrombocytopenia (18.7%). The overall complication rate of the thrombocytosis cohort was 14.6%. In comparison to normal platelet count, low-normal thrombocytopenia, mild thrombocytopenia, moderate-to-severe thrombocytopenia, and thrombocytosis were identified by multivariate analysis as significant predictors of overall complications (odds ratios [ORs] of 1.12, 2.15, 2.43, 2.71, respectively), postoperative anemia requiring transfusion (ORs of 1.63, 3.45, 5.97, 4.21, respectively), and minor complications (ORs of 1.39, 2.64, 3.40, 3.34, respectively). Minor complications include progressive renal insufficiency, urinary tract infection, transfusions within 72 hours after surgery, pneumonia, and superficial incisional surgical site infection.

Conclusion

Increasing severity of thrombocytopenia correlated with higher overall postoperative complication rates following TSA. Interestingly, patients with thrombocytosis had the highest overall postoperative complication rates among all cohorts included in this study. Platelet counts are often the reflection of other comorbidities and a good indicator of patient's general health status. Long-term optimization of abnormal platelet counts may potentially reduce surgical complications.