Preventing Acute Kidney Injury and Hypotension After Elective Total Joint Arthroplasty Is Possible: An Update to an Established Multidisciplinary Protocol.

INTRODUCTION: Based on preoperative and perioperative risk factors that have been found to correlate with the development of acute kidney injury (AKI), our institution developed a protocol aimed at managing and improving outcomes in all elective THA and TKA patients. This article highlights the continued success and growth of our protocol aimed at decreasing AKI and hypotension in elective total joint arthroplasty patients. METHOD: A multidisciplinary team comprising orthopaedic surgeons, nephrologists, anesthesiologists, cardiologists, and internal medicine hospitalists created a comprehensive protocol aimed at decreasing complications after elective joint arthroplasty and improving clinical outcomes across multiple hospitals. Patient demographics, hospital length of stay, readmission rates, mortality, and postoperative AKI and hypotension incidences were recorded and compared between preprotocol phase I (initial protocol implementation) and phase II (protocol expansion across 10 hospitals) patient cohorts. RESULTS: Overall, 3,222 patients over 56 months and 10 hospitals were included. Our phase II AKI rate (0.6%) was significantly lower than our preprotocol rate (6.2%, P < 0.01) and statistically similar to our phase I rate (1.2%, P = 0.61). Our hypotension rate in phase II (6.8%) was significantly lower than our preprotocol rate (12.7%, P < 0.01) but statistically similar to our phase I rate (5.9%, P = 0.40). Furthermore, a significant decrease was observed in hospital length of stay (P < 0.01) over time, but no difference was observed in readmission (P = 0.59) and mortality rates (P = 1.00) over time. DISCUSSION: This protocol-driven interventional study provides a detailed and successful multidisciplinary method to manage and decrease rates of AKI and hypotension in a large patient cohort across multiple hospital centers.

Reducing Hypotension and Acute Kidney Injury in the Elective Total Joint Arthroplasty Population: A Multi-Disciplinary Approach.

BACKGROUND: When critically analyzing our hospital system's rate of hypotension and acute kidney injury (AKI) after total joint arthroplasty, our incidence rates (14.54%, 6.02%) were much higher than our peers (7.17%, 2.03%) and national rates (2.0%, 3.3%). We present a multi-disciplinary management intervention that aimed to decrease overall complication rates. METHOD: A multi-disciplinary team implemented a protocol at our suburban hospital to limit complication rates after joint replacement surgery. Hypotension, AKI, length of stay (LOS), re-admission rates, and mortality rates were compared before the protocol was implemented, after protocol implementation, and after protocol integration into our EMR (electronic medical record). RESULTS: In total, 1233 patients over 36 months were followed. Hypotension rates after protocol implementation into EMR (group 3) were significantly lower than rates before the protocol (group 1) (P = .002), with rates after protocol implementation without EMR (group 2) trending toward a significant decrease from group 1 (P = .064). AKI rates in group 3 were significantly lower than group 1 (P = .000) and group 2 (P = .006). No difference was seen in hypotension rates between group 2 and 3 (P = .792) or AKI rates between group 1 and 2 (P = .533). Finally, no significant difference was seen between groups in LOS (P = .560), re-admission rates (P = .378), and mortality rates (all 0.0%). CONCLUSION: By implementing a comprehensive electronic protocol consisting of pre-operative risk stratification, multi-disciplinary medical optimization, and an evolving post-operative management plan, significant decreases in hypotension and AKI can be seen.

Two-screw femoral neck fracture fixation: a biomechanical analysis of 2 different configurations.

In the study reported here, we evaluated 2-screw femoral neck fixation. Femoral necks from 5 paired fresh-frozen cadavers were fractured and then fixed with two 7.3-mm cannulated cancellous screws. Vertical (parallel screws in sagittal plane of femoral neck) and horizontal (parallel screws in superior aspect of femoral neck) configurations were used for each matched pair. Mechanical testing was performed. Load, displacement, and stiffness at the yield point were significantly higher in the horizontal group, which also had a higher mean maximal failure load (P = .019). Preliminary data suggest that 2 horizontal screws in the superior aspect of the femoral neck provide more secure fixation than 2 vertical screws.

Arthroscopically-assisted removal of retrograde intramedullary femoral nails.

Retrograde nailing of femoral shaft fractures has become more prevalent as a result of its growing acceptance and familiarity to orthopaedic surgeons. Nail removal is occasionally indicated, which may require a formal arthrotomy. We describe an arthroscopic removal technique that has several advantages. The percutaneous technique imparts less morbidity than a more extensive arthrotomy. More importantly, additional intra-articular pathology can be thoroughly assessed and treated, such as meniscal tears and chondral injury, which may have occurred at the time of injury. These are potential causes of knee pain, which usually cannot be properly diagnosed without arthroscopy. Our findings also support the existence of a stable fibrous cap, which forms over the entry portal of a well-seated retrograde femoral nail as well as no evidence of intra-articular metallosis.

Bone morphogenetic proteins are expressed by both bone-forming and non-bone-forming lesions.

CONTEXT: Bone morphogenetic proteins (BMPs) are thought to be responsible for bone formation; they cause bone to form in soft tissues and are clinically used in helping fracture union or tumor reconstructions. Skeletal metastases from epithelial tumors may be either bone-forming (blastic) or non-bone-forming (lytic). OBJECTIVE: We studied the expression of BMPs in a variety of primary and secondary lesions of bone (both bone-forming and non-bone-forming) to determine if there was a consistent relationship between bone formation and BMP expression. DESIGN: We compared a bone-forming lesion (fibrous dysplasia) with a non-bone-forming lesion (desmoid tumor), using reverse transcription-polymerase chain reaction, Northern blot analysis, and immunohistochemistry to detect BMPs. We also studied a number of non-bone-forming secondary lesions (carcinomas that formed lytic metastases to the skeleton) and found BMP production in most of these tumors. RESULTS: We found that BMPs were expressed in both bone-forming and non-bone-forming benign musculoskeletal lesions. In the first part of the study, BMPs were found in both fibrous dysplasia and desmoid tumors. Bone morphogenetic proteins were also expressed by several tumors. In the next part of the study (paraffin-embedded tissue), BMPs were expressed by a variety of tumors, irrespective of the radiological nature (blastic or lytic) of their metastases. CONCLUSIONS: We conclude that BMP production alone cannot explain bone formation, and other factors either alone or in combination may be responsible for blastic metastases to the skeleton and for bone formation by primary bone lesions, such as fibrous dysplasia.

Bone Morphogenetic Proteins Are Expressed by Both Bone-Forming and Non-Bone-Forming Lesions.

Context.-Bone morphogenetic proteins (BMPs) are thought to be responsible for bone formation; they cause bone to form in soft tissues and are clinically used in helping fracture union or tumor reconstructions. Skeletal metastases from epithelial tumors may be either bone-forming (blastic) or non-bone-forming (lytic).Objective.-We studied the expression of BMPs in a variety of primary and secondary lesions of bone (both bone-forming and non-bone-forming) to determine if there was a consistent relationship between bone formation and BMP expression.Design.-We compared a bone-forming lesion (fibrous dysplasia) with a non-bone-forming lesion (desmoid tumor), using reverse transcription-polymerase chain reaction, Northern blot analysis, and immunohistochemistry to detect BMPs. We also studied a number of non-bone-forming secondary lesions (carcinomas that formed lytic metastases to the skeleton) and found BMP production in most of these tumors.Results.-We found that BMPs were expressed in both bone-forming and non-bone-forming benign musculoskeletal lesions. In the first part of the study, BMPs were found in both fibrous dysplasia and desmoid tumors. Bone morphogenetic proteins were also expressed by several tumors. In the next part of the study (paraffin-embedded tissue), BMPs were expressed by a variety of tumors, irrespective of the radiological nature (blastic or lytic) of their metastases.Conclusions.-We conclude that BMP production alone cannot explain bone formation, and other factors either alone or in combination may be responsible for blastic metastases to the skeleton and for bone formation by primary bone lesions, such as fibrous dysplasia.

Evaluation and treatment of spinal injuries in the patient with polytrauma.

Spinal injuries occur frequently in the patient with polytrauma making the knowledge of the evaluation and treatment of these injuries invaluable to the trauma team. In the immediate moments after these injuries, critical steps can be taken to prevent additional injury and insure maximum neurologic and functional recovery of the patient. A simple, standardized approach to treating the patient at the scene, examining the patient in the trauma admitting area, ordering appropriate radiographic studies, and instituting early treatment can markedly influence a patient's maximal recovery. Furthermore, background knowledge in the classification and ultimate treatment goals allows for an effective communication between the initial treating team and the spinal surgeons involved. The work on indicators of potential spinal instability by White and Panjabi and the three-column classification of spinal injuries of Denis lends insight to the potential consequences of spinal trauma. A thorough appreciation of these concepts puts evaluation and treatment of these injuries into a logical framework with which spinal injuries initially can be approached.

Cytokines in patients with polytrauma.

Patients with multiple injuries have alterations in hemodynamic, metabolic, and immune responses that largely are orchestrated by endogenous mediators referred to as cytokines. At the molecular level cytokines act as architects constructing a blueprint which ultimately will become the clinical "Big Picture"; however, the exact role and extent each cytokine has is still in question. In addition, the surface of research opportunities has nearly been scratched regarding the best way to control or manipulate the cytokine response in efforts to improve care for the trauma patient. Systemically organisms respond to injury regardless of the cause (hemorrhage, ischemia, reperfusion, fracture, and tissue damage) by attempting to restore homeostasis, which involves a coordination of the immune, cardiovascular, endocrine, and nervous systems. This systemic response can result in severe immunologic compromise that threatens the survival of patients with trauma. It seems that it is this balance or imbalance of cytokines, along with other associative factors, that controls the eventual clinical pathway a patient will take. Blood mediator concentrations often parallel the inflammatory process, and high levels of cytokines can be followed by severe organ dysfunction. Certain cytokine levels, such as the interleukins, can be used in predictive ways to correlate organ failure in multiply injured patients. Although much more research must be done, there is great promise in the study of cytokines through basic science research and clinical trials.

Organizing the orthopaedic trauma association mass casualty response team.

Physicians and surgeons in the United States have become increasingly aware of the requirement for an organized response to mass casualty and disaster situations. This has not always been the case. The terrorist acts in Oklahoma City in 1995 and at the World Trade Center in 1993 and 2001 showed the inefficiencies and confusion of the civilian managed disaster response. Trauma surgeons are uniquely suited to play a leadership role in the planning and coordination of disaster care because of their integration in prehospital emergency medical systems and trauma centers. The Orthopaedic Trauma Association has developed strategies to facilitate the orthopaedic response to mass casualties and to develop an educated approach to disaster management. The current initiatives include the establishment of a link with the American College of Surgeons Committee on Trauma in addition to the development of training programs for orthopaedic surgeons as responders to disaster and mass casualty situations. A team of volunteer orthopaedic traumatologists also has been credentialed to become part of the National Disaster Medical System's International Medical-Surgical Response Team.

Mechanical properties of dilated human ascending aorta.

Dilation of the ascending aorta, associated with Marfan Syndrome, bicuspid aortic valve, or advanced age, may lead to aortic dissection and rupture. Mathematical models can be used to assess the relative importance of increased wall stresses and decreased strength in these mechanical failures. To obtain needed inputs for such models, mechanical properties of dilated human ascending aorta were measured in vitro. Specimens for opening angle, biaxial elastic, and uniaxial circumferential strength tests were cut from excised tissue obtained from 54 patients (age 18-81 years) undergoing elective aortic graft replacement surgery. Opening angle was significantly greater in patients older than 50 years (262 degrees + 76 degrees, n = 21) compared to younger patients (202 degrees +/- 70 degrees, n = 13). All biaxial elastic specimens (n = 40) exhibited nonlinear stress-strain behavior. Rapid increases in circumferential and axial stresses occurred at lower strains in the older patient group than in the younger. Mean strength was significantly lower in older patients (1.35 +/- 0.37 MPa, n= 14) than younger (2.04 +/- 0.46 MPa, n = 11, age <50 years). These changes in mechanical properties suggest that age may influence the risk of aortic dissection or rupture of dilated ascending aorta.

From object to subject: pastoral supervision as an intersubjective activity.

The author sketches the development of psychoanalysis in terms of its trends from notions of objectivity to intersubjectivity and how this movement can inform contemporary pastoral supervision. The article argues that these same trends may be noted in the development of contemporary educational and theological theories.