The role of ultrasound in predicting non-invasive ventilation outcomes: a systematic review.

Purpose: To systematically review and compare ultrasonographic methods and their utility in predicting non-invasive ventilation (NIV) outcomes. Methods: A systematic review was performed using the PubMed, Medline, Embase, and Cochrane databases from January 2015 to March 2023. The search terms included the following: ultrasound, diaphragm, lung, prediction, non-invasive, ventilation, and outcomes. The inclusion criteria were prospective cohort studies on adult patients requiring non-invasive ventilation in the emergency department or inpatient setting. Results: Fifteen studies were analyzed, which comprised of 1,307 patients (n = 942 for lung ultrasound score studies; n = 365 patients for diaphragm dysfunction studies). Lung ultrasound scores (LUS) greater than 18 were associated with NIV failure with a sensitivity 62-90.5% and specificity 60-91.9%. Similarly, a diaphragm thickening fraction (DTF) of less than 20% was also associated with NIV failure with a sensitivity 80-84.6% and specificity 76.3-91.5%. Conclusion: Predicting NIV failure can be difficult by routine initial clinical impression and diagnostic work up. This systematic review emphasizes the importance of using lung and diaphragm ultrasound, in particular the lung ultrasound score and diaphragm thickening fraction respectively, to accurately predict NIV failure, including the need for ICU-level of care, requiring invasive mechanical ventilation, and resulting in higher rates of mortality.

Higher albumin levels on admission predict better prognosis in patients with confirmed COVID-19.

BACKGROUND: Research surrounding COVID-19 (coronavirus disease 2019) is rapidly increasing, including the study of biomarkers for predicting outcomes. There is little data examining the correlation between serum albumin levels and COVID-19 disease severity. The purpose of this study is to evaluate whether admission albumin levels reliably predict outcomes in COVID-19 patients. METHODS: We retrospectively reviewed 181 patients from two hospitals who had COVID-19 pneumonia confirmed by polymerase chain reaction (PCR) testing and radiologic imaging, who were hospitalized between March and July 2020. We recorded demographics, COVID-19 testing techniques, and day of admission labs. The outcomes recorded included the following: venous thromboembolism (VTE), acute respiratory distress syndrome (ARDS), intensive care unit (ICU) admission, discharge with new or higher home oxygen supplementation, readmission within 90 days, in-hospital mortality, and total adverse events. A multivariate modified Poisson regression analysis was then performed to determine significant predictors for increased adverse events in patients with COVID-19 pneumonia. RESULTS: A total of 109 patients (60.2%) had hypoalbuminemia (albumin level < 3.3 g/dL). Patients with higher albumin levels on admission had a 72% decreased risk of developing venous thromboembolism (adjusted relative risk [RR]:0.28, 95% confidence interval [CI]:0.14-0.53, p<0.001) for every 1 g/dL increase of albumin. Moreover, higher albumin levels on admission were associated with a lower risk of developing ARDS (adjusted RR:0.73, 95% CI:0.55-0.98, p = 0.033), admission to the ICU (adjusted RR:0.64, 95% CI:0.45-0.93, p = 0.019), and were less likely to be readmitted within 90 days (adjusted RR:0.37, 95% CI:0.17-0.81, p = 0.012). Furthermore, higher albumin levels were associated with fewer total adverse events (adjusted RR:0.65, 95% CI:0.52-0.80, p<0.001). CONCLUSIONS: Admission serum albumin levels appear to be a predictive biomarker for outcomes in COVID-19 patients. We found that higher albumin levels on admission were associated with significantly fewer adverse outcomes, including less VTE events, ARDS development, ICU admissions, and readmissions within 90 days. Screening patients may lead to early identification of patients at risk for developing in-hospital complications and improve optimization and preventative efforts in this cohort.

Return to Work After Total Joint Arthroplasty: A Predictive Model.

Returning to work after surgery is a primary concern of patients who are contemplating total joint arthroplasty (TJA). The ability to return to work has enormous influence on the patient's independence, financial well-being, and daily activities. The goal of this study was to determine the independent patient variables that predict return to work as well as to create a predictive model. From June 2017 to December 2017, a total of 391 patients who underwent primary TJA (243 hips, 148 knees) were prospectively enrolled in the study to obtain information on return to work after surgery. Patients were sent a series of questions in a biweekly survey. Information was collected on the physical demands of their occupation, the number of hours spent standing, the limitations to return to work, and the use of assistive devices. Bivariate analysis was performed, and a multiple linear regression model was created. Most (89.6%) patients returned to work within 12 weeks of surgery. Patients who underwent total hip arthroplasty returned to work earlier than those who underwent total knee arthroplasty (5.56 vs 7.79 weeks, respectively). Analysis showed the following independent predictors for faster return to work: self-employment, availability of light-duty work, male sex, and higher income. Predictors for slower return to work included a physically demanding occupation (at least 50% physical duties), knee arthroplasty, longer length of stay, and a job requiring more hours spent standing. This model reported an adjusted R2 of 0.332. The findings provide an objective predictive model of the patient- and procedure-specific characteristics that affect postoperative return to work. Surgeons should consider these factors when counseling patients on their postoperative expectations. [Orthopedics. 2020;43(5):e415-e420.].

Outcomes and predictors of treatment failure following two-stage total joint arthroplasty with articulating spacers for evolutive septic arthritis.

BACKGROUND: The treatment strategy for evolutive septic arthritis (SA) with coexistent degenerative joint disease is not well established. The purposes of this study were to 1) investigate treatment outcome and potential risk factors of treatment failure in patients with evolutive SA following two-stage procedure, including insertion of an antibiotic-loaded spacer at the first stage and subsequent implantation of a new prosthesis; and 2) determine the performance of serum erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and Interleukin-6 (IL-6) in predicting persisting infection at second-stage procedure. METHODS: We retrospectively reviewed 74 patients with evolutive SA of hips and knees who underwent a two-stage TJA between 2008 and 2015. The treatment success was defined according to the modified Delphi criteria and Kaplan-Meier survivorship curves were constructed to determine treatment success. A Cox regression model was performed to identify risk factors for treatment failure. Receiver operating characteristic (ROC) curves were generated to determine the prognostic value of ESR, CRP, and IL-6 in predicting persistent infection before second-stage prostheses implantation. RESULTS: Overall, the treatment success rate was 93% for hips and 100% for knees after the first-stage surgery. The treatment success rate was 89% for hips and 84% for knees after second-stage prosthesis implantation with a mean follow-up of 4.7 (range, 2.2 to 10.8) years. Older age (Hazard ratio [HR] [per 10-year increase], 1.20; 95% confidential interval [CI], 1.11 to 1.62), higher preoperative CRP level (HR [per 1-mg/dL increase], 1.15; 95% CI, 1.04 to 1.28) and resistant organism (HR, 13.96; 95% CI, 3.29 to 19.20) were associated with an increased risk of treatment failure. All serologic tests presented limited values in predicting persisting infection, with the area under ROC curve of ESR, CRP, IL-6 and combination of the three markers was 57.8, 61.6, 60.3, and 62.1%, respectively. CONCLUSIONS: Two-stage TJA is an adequate management of infection control in patients with evolutive SA. The three potential risk factors (old age, high preoperative CRP, and resistant organism profile) may predict treatment failure following a two-stage procedure for evolutive SA. Additionally, serum ESR, CRP, and IL-6 had no benefit in predicting persisting infection before second-stage prostheses implantation. These findings may be useful when treating patients with evolutive SA.

Perioperative Telephone Encounters Should Be Included in the Relative Value Scale Update Committee Review of Time Spent on Total Hip and Knee Arthroplasty.

BACKGROUND: Providing care for patients undergoing hip and knee arthroplasty requires substantial effort beyond the actual replacement surgery to ensure a safe, clinical, and economically effective outcome. Recently, the Centers for Medicare and Medicaid Services has stated that the procedural codes for total hip (THA) and total knee arthroplasty (TKA) are potentially misvalued and has asked for a review by the Relative Value Scale Update Committee (RUC). The purpose of this study is to quantify one of the additional work efforts associated with telephone encounters during the perioperative episode of care. METHODS: We retrospectively reviewed all 47,841 telephone calls from patients to our office from 2015 to 2017 in a consecutive series of 3309 patients who underwent TKA and 3651 patients who underwent THA. We recorded reasons for communication, amount of communication, and the caller identity for both 30 days preoperatively and 90 days postoperatively. We then used the RUC Building Block Method to calculate the preservice and postservice work included in a review of the time and intensity of the codes for THA and TKA. RESULTS: The average number of preoperative patient calls per patient was 2.31 for TKA and 2.44 for THA, and the average number of postoperative calls was 5.01 for TKA and 4.00 for THA. The most common reasons for patient calls were perioperative care instructions, medications, medical clearance, paperwork/insurance, and complications. Using the RUC-approved work relative value units (wRVUs) assigned to each telephone encounter, an additional 1.83 wRVUs for perioperative telephone encounters for TKA and 1.61 for THA should be assigned. CONCLUSIONS: Providing patients with appropriate support during the arthroplasty episode of care requires substantial telephonic support, which should be acknowledged. As the RUC considers reviewing the time and intensity spent on perioperative care for patients undergoing THA and TKA, they should consider appropriately documenting the amount of work required for telephone communication.

Positive Alpha-defensin at Reimplantation of a Two-stage Revision Arthroplasty Is Not Associated with Infection at 1 Year.

BACKGROUND: Diagnosing periprosthetic joint infection (PJI) represents a challenge that relies on multiple clinical and laboratory criteria that may not be consistently present. The synovial alpha-defensin-1 (AD-1) test has been shown to correlate accurately with the Musculoskeletal Infection Society (MSIS) criteria for the diagnosis of PJI, however, its association with persistent PJI has not been elucidated in the setting of patients receiving antibiotic spacers during second-stage reimplantation. Applying a Delphi-based consensus to define successful eradication of PJI offers an opportunity to test the utility of AD-1 in this setting. QUESTIONS/PURPOSES: (1) Can the AD-1 test determine whether infection has been controlled using the Delphi criteria for persistent PJI as a surrogate for infection eradication during two-stage revision for PJI treatment with a spacer? (2) How does the performance of the AD-1 test compare with the MSIS criteria? METHODS: This was a multicenter analysis of retrospectively collected data on patients who underwent a two-stage revision arthroplasty between May 2014 and July 2016. We included patients who had a previously confirmed PJI and received a cement spacer, underwent the second stage, had MSIS criteria data and a synovial fluid AD-1 test, and had a minimum followup of 1 year. We were unable to determine for all study sites how many patients had the test but did not meet all the criteria and so could not be studied; however, we were able to identify 69 patients (43 knees, 26 hips) who met all criteria. During the period in question, indications for use of AD-1 varied by surgeon; however, during that time, in general if a surgeon ordered it as part of the initial workup, the test would have been repeated before the second-stage reimplantation procedure. To assess the validity of AD-1 against persistence of PJI criteria at 1 year, the following were calculated using the Delphi criteria for persistent PJI as the gold standard: sensitivity, specificity, positive and negative predictive values, accuracy, and area under the curve (AUC) with 95% confidence intervals (CIs). Concordance index (c-index) and its Wald 95% CI with receiver operating characteristic (ROC) curve were calculated in relation to Delphi criteria for persistent PJI using AD-1 and then MSIS criteria. The two c-indices of AD-1 and MSIS were compared using the DeLong nonparametric approach. RESULTS: The AD-1 test showed poor sensitivity (7%; 95% CI, 0.2-34), and poor overall accuracy (73%; 95% CI, 60-83; AUC = 0.5; 95% CI, 0.3-0.6) in detecting infection eradication at 1 year. The c-index for AD-1 versus Delphi criteria for persistent PJI was 0.519 (95% CI, 0.44-0.60), and the c-index for MSIS criteria versus Delphi criteria for persistent PJI was 0.518 (95% CI, 0.49-0.54), suggesting the weak diagnostic abilities of these models. The contrast estimate between MSIS criteria and AD-1 were not different from one another at -0.001 (95% CI%, -0.09 to 0.09; p = 0.99). CONCLUSIONS: We found that a positive synovial fluid AD-1 test correlated poorly with the presence of persistent infection 1 year after two-stage revision arthroplasty for PJI. For this reason, we recommend against the routine use of AD-1 in patients with cement spacers, until or unless future studies demonstrate that the test is more effective than we found it to be. LEVEL OF EVIDENCE: Level IV, diagnostic study.

Failure After 2-Stage Exchange Arthroplasty for Treatment of Periprosthetic Joint Infection: The Role of Antibiotics in the Cement Spacer.

BACKGROUND: Failure after a 2-stage exchange surgery for periprosthetic joint infection (PJI) is high. Previous studies demonstrated that positive cultures at reimplantation are associated with failure afterward. The aim of this multicenter study was to define the role of antibiotics in the cement spacer in relation to reimplantation cultures and subsequent failure. METHODS: We retrospectively evaluated 2-stage exchange procedures between 2000 and 2015. Culture-negative PJIs, cases in which no cultures were obtained during reimplantation, and cases without data on cement spacers were excluded. RESULTS: Three hundred forty-four cases were included. The rate of positive cultures during reimplantation was 9.5% for cement spacers containing a glycopeptide (27/284) (with or without an aminoglycoside) vs 21.7% for those containing monotherapy with an aminoglycoside (13/60) (P = .008), and was mostly attributed by a reduction in coagulase-negative staphylococci (CoNS) (17% vs 2%, P < .001). The failure rate was >2-fold higher at 40.0% (16/40) in cases with positive cultures at reimplantation compared to 15.8% (48/304) for those with negative cultures (P < .001). Overall, a glycopeptide in the cement spacer was not associated with a lower failure rate (18% vs 23%, P = .3), but was associated with lower failure due to CoNS (2.5% vs 13.3%, P < .001). CONCLUSIONS: In a 2-stage exchange procedure for PJI, adding a glycopeptide to the cement spacer reduces the rate of positive cultures during reimplantation and is associated with a lower failure rate due to CoNS afterward.

Web-Based, Self-Directed Physical Therapy After Total Hip Arthroplasty Is Safe and Effective for Most, but Not All, Patients.

BACKGROUND: Recent data suggested that unsupervised, self-directed physical therapy (SDPT) is both safe and efficacious for patients undergoing total hip arthroplasty (THA) and that formal outpatient physical therapy (OPPT) may not be routinely required. The purpose of this study was to evaluate the routine use of an SDPT program in a nonselect patient population. METHODS: This is a multi-surgeon, single-institution, retrospective study of 941 consecutive patients discharged home, from January 2016 to December 2016, after primary, unilateral THA and enrolled in a web-based SDPT program. Patients were seen 4 weeks after surgery and OPPT was prescribed for perceived need, patient request, or if unable to use the web-based program. Patient-reported outcomes, medical comorbidities, and assessment of home environment were prospectively recorded. RESULTS: Overall, 646 of 941 patients (68.7%) were not prescribed OPPT (SDPT-only group) while 295 of 941 patients (31.3%) were prescribed OPPT (SDPT + OPPT group). In the SDPT + OPPT group, 88.2% were for perceived need, 10.8% for patient request, and 1.0% due to inability to use the web-based platform. Multivariate analysis identified male sex (odds ratio, 0.64; 0.45-0.90; P = .012) and a higher preoperative Short Form-12 physical component (odds ratio, 0.98; 0.96-0.99; P = .036) as independent variables protective against requiring OPPT. At a minimum 6-month follow-up, the SDPT-only group had statistically higher hip disability and osteoarthritis outcome score junior compared to the SDPT + OPPT cohort (85.0 vs 80.9; P = .012). CONCLUSION: Web-based SDPT is safe and effective for most, but not all, patients eligible for home discharge after THA. It is critical to preserve OPPT services for the one-third of patients who require them. LEVEL OF EVIDENCE: Level III.

Culture-Negative Periprosthetic Joint Infection: An Update on What to Expect.

BACKGROUND: Culture-negative periprosthetic joint infection (PJI) is a challenging condition to treat. The most appropriate management of culture-negative PJI is not known, and there is immense variability in the treatment outcome of this condition. The purpose of this study was to elucidate the characteristics, outcomes, and risk factors for failure of treatment of culture-negative PJI. METHODS: A retrospective review of 219 patients (138 hips and 81 knees) who had undergone surgery for the treatment of culture-negative PJI was performed utilizing a prospectively collected institutional PJI database. PJIs for which the results of culture were unavailable were excluded. An electronic query and manual review of the medical records were completed to obtain patient demographics, treatment, microbiology data, comorbidities, and other surgical characteristics. Treatment failure was assessed using the Delphi consensus criteria. RESULTS: The prevalence of suspected culture-negative PJI was 22.0% (219 of 996), and the prevalence of culture-negative PJI as defined by the Musculoskeletal Infection Society (MSIS) was 6.4% (44 of 688). Overall, the rate of treatment success was 69.2% (110 of 159) in patients with >1 year of follow-up. Of the 49 culture-negative PJIs for which treatment failed, 26 (53.1%) subsequently had positive cultures; of those 26, 10 (38.5%) were positive for methicillin-sensitive Staphylococcus aureus. The rate of treatment success was greater (p = 0.019) for patients who had 2-stage exchange than for those who underwent irrigation and debridement. CONCLUSIONS: The present study demonstrates that culture-negative PJI is a relatively frequent finding with unacceptable rates of treatment failure. Every effort should be made to isolate the infecting organism prior to surgical intervention, including extending the incubation period for cultures, withholding antibiotics prior to obtaining culture specimens, and possibly using newly introduced molecular techniques. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Postoperative Blood Glucose Levels Predict Infection After Total Joint Arthroplasty.

BACKGROUND: Perioperative hyperglycemia has many etiologies, including medication, impaired glucose tolerance, uncontrolled diabetes mellitus, or stress, the latter of which is common in patients postoperatively. Our study investigated the influence of postoperative blood glucose levels on periprosthetic joint infection after elective total joint arthroplasty to determine a threshold for glycemic control for which surgeons should strive during a patient's hospital stay. METHODS: A single-institution retrospective review was conducted on 24,857 primary total joint arthroplasties performed from 2001 to 2015. Of these, 13,196 had a minimum follow-up of 1 year (mean, 5.9 years). Postoperative day 1 morning blood glucose levels were utilized and were correlated with periprosthetic joint infection, as defined by the International Consensus Group on Periprosthetic Joint Infection. Multivariable analysis was used to determine the influence of several important covariates on infection. An alpha level of 0.05 was used to determine significance. RESULTS: The rate of periprosthetic joint infection increased linearly from blood glucose levels of ≥115 mg/dL. Multivariable analysis revealed that blood glucose levels were significantly associated with periprosthetic joint infection (p = 0.028). The optimal blood glucose threshold to reduce the likelihood of periprosthetic joint infection was 137 mg/dL. The periprosthetic joint infection rate in the entire cohort was 1.59% (1.46% in patients without diabetes compared with 2.39% in patients with diabetes; p = 0.001). There was no significant association between blood glucose level and periprosthetic joint infection in patients with diabetes (p = 0.276), although there was a linear trend. CONCLUSIONS: The relationship between postoperative blood glucose levels and periprosthetic joint infection increased linearly, with an optimal cutoff of 137 mg/dL. Immediate and strict postoperative glycemic control may be critical in reducing postoperative complications, as even mild hyperglycemia was significantly associated with periprosthetic joint infection. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

High-load preconditioning of human soft tissue hamstring grafts: An in vitro biomechanical analysis.

PURPOSE: In order to minimize viscoelastic elongation of ACL reconstruction grafts, preconditioning protocols have been employed in clinical practice prior to final graft fixation. The purpose of this study was to evaluate two separate high-load static preconditioning protocols of double-looped semitendinosus-gracilis grafts and compare these results to both a current clinical protocol and a control group with no preconditioning protocol applied. It was hypothesized that a high-load, static preconditioning protocol would minimize graft elongation during a simulated progressive early rehabilitation compared to both the "89 N" clinical protocol and control groups. METHODS: Grafts were randomly allocated into four preconditioning study groups: (1) control (no preconditioning), (2) clinical protocol (89 N for 15 min), (3) high-load, short duration (600 N for 20 s), and (4) high-load, long duration (600 N for 15 min). After preconditioning, grafts were cyclically loaded between 10 and 400 N at 0.5 Hz for 450 cycles to simulate early postoperative rehabilitation. Graft displacement (elongation) was recorded during both preconditioning and cyclic loading. RESULTS: Increased preconditioning load magnitude and duration significantly reduced graft elongation during cyclic loading (p < 0.05) which corresponded to an inverse relationship with increased elongation during preconditioning. The "600 N for 15 min" protocol resulted in significantly less elongation during simulated early rehabilitation than both the control group and the "89 N for 15 min" protocol (p < 0.001, p < 0.05). CONCLUSIONS: Graft elongation during simulated early rehabilitation was significantly reduced by a high-load preconditioning protocol applied for an extended period of time compared to a current common clinical protocol and grafts that were not preconditioned. In addition, the amount of elongation during simulated early rehabilitation was similar between grafts preconditioned using the current clinical practice protocol and the high-load/short-duration protocol, implying that the latter could potentially induce the same viscoelastic changes in soft tissue grafts as the current clinical practice. The "600 N for 20 s" preconditioning protocol may provide similar postoperative results as the clinical protocol, "89 N for 15 min", and also reduce or maintain operative time. A high-load preconditioning protocol that reduces graft elongation may benefit patients undergoing ACL reconstruction, especially for cases of failed primary reconstruction, genu recurvatum, and increased tibial slope, where maintaining graft length is imperative to restore knee stability.

Biomechanical Results of Lateral Extra-articular Tenodesis Procedures of the Knee: A Systematic Review.

PURPOSE: To systematically review and compare biomechanical results of lateral extra-articular tenodesis (LET) procedures. METHODS: A systematic review was performed using the PubMed, Medline, Embase, and Cochrane databases. The search terms included the following: extraarticular, anterolateral, iliotibial, tenodesis, plasty, augmentation, procedure, reconstruction, technique, biomechanics, kinematic, robot, cadaver, knee, lateral tenodesis, ACL, Marcacci, Lemaire, Losee, Macintosh, Ellison, Andrews, Hughston, and Muller. The inclusion criteria were nonanatomic, in vitro biomechanical studies, defined as in vitro investigations of joint motion resulting from controlled, applied forces. RESULTS: Of the 10 included studies, 7 analyzed anterior tibial translation and reported that isolated LET procedures did not restore normal anterior stability to the anterior cruciate ligament (ACL)-deficient knee. Seven of the 8 studies analyzing tibial rotation reported a reduction in internal tibial rotation across various flexion angles in the ACL-deficient knee when compared with the native state. Five studies reported a reduction in intra-articular graft force with the addition of an LET. Two studies evaluated length change patterns, graft course, and total strain range and found that reconstruction techniques in which the graft attached proximal to the lateral epicondyle and coursed deep to the fibular collateral ligament were most isometric. CONCLUSIONS: In the ACL-deficient knee, LET procedures overconstrained the knee and restricted internal tibial rotation when compared with the native state. In addition, isolated LET procedures did not return normal anterior stability to the ACL-deficient knee but did significantly reduce anterior tibial translation and intra-articular graft forces during anteriorly directed loading. CLINICAL RELEVANCE: Combined injury to the ACL and anterolateral structures has been reported to exhibit greater anterolateral rotatory instability when compared with isolated ACL injuries. Despite the reported risk of joint over-constraint, consideration should be given to reconstructing the anterolateral structures and the ACL concurrently to maximally restore both anterior tibial translation and rotatory stability.