Veno-Arterial Extracorporeal Membrane Oxygenation Rescue in a Patient With Pulmonary Hypertension Presenting for Revision Total Hip Arthroplasty: A Case Report and Narrative Review.

Patients with pulmonary hypertension (PH) are at an increased risk of perioperative morbidity and mortality when undergoing non-cardiac surgery. We present a case of a 57-year-old patient with severe PH, who developed cardiac arrest as the result of right heart failure, undergoing a revision total hip arthroplasty under combined spinal epidural anesthesia. Emergent veno-arterial (VA) extracorporeal membrane oxygenation (ECMO) was undertaken as rescue therapy during the pulmonary hypertensive crisis and a temporizing measure to provide circulatory support in an intensive care unit (ICU). We present a narrative review on perioperative management for patients with PH undergoing non-cardiac surgery. The review goes through the updated hemodynamic definition, clinical classification of PH, perioperative morbidity, and mortality associated with PH in non-cardiac surgery. Pre-operative assessment evaluates the type of surgery, the severity of PH, and comorbidities. General anesthesia (GA) is discussed in detail for patients with PH regarding the benefits of and unsubstantiated arguments against GA in non-cardiac surgery. The literature on risks and benefits of regional anesthesia (RA) in terms of neuraxial, deep plexus, and peripheral nerve block with or without sedation in patients with PH undergoing non-cardiac surgery is reviewed. The choice of anesthesia technique depends on the type of surgery, right ventricle (RV) function, pulmonary artery (PA) pressure, and comorbidities. Given the differences in pathophysiology and mechanical circulatory support (MCS) between the RV and left ventricle (LV), the indications, goals, and contraindications of VA-ECMO as a rescue in cardiopulmonary arrest and pulmonary hypertensive crisis in patients with PH are discussed. Given the significant morbidity and mortality associated with PH, multidisciplinary teams including anesthesiologists, surgeons, cardiologists, pulmonologists, and psychological and social worker support should provide perioperative management.

Cold saline lavage for removal of incarcerated porous ingrowth stems.

A patient with a history of total knee arthroplasty and 5 subsequent revisions presented with pain. His preoperative construct consisted of a revision implant with porous in-growth stem extensions. He was indicated for revision surgery for a painful implant with progressive arthrofibrosis. The surgery proceeded uneventfully until we were unable to loosen the proximal portion of the ingrown femoral stem. After the distal femur was removed, a trephine was used to break the bone ingrowth from the distal portion of the stem. Flexible osteotomes were used to loosen the bone-prosthetic interface, but they were unable to penetrate deep enough, and they eventually bent under the applied loads. Nonflexible osteotomes were also used without success, and we were still unable to remove the stem from within the femur. Slap hammers, vice grips, and other devices were used to try to remove the stem, but attempts were unsuccessful. We hung a 3-liter bag of ice-cold (4 °C) saline and ran all 3 liters of saline, under gravity pressure, retrograde down the femoral shaft in an attempt to contract the metal and allow for the removal of the stem. We then attached a stem extension screw to the incarcerated femoral stem and were able to remove it with minimal effort using a back-slap device. We inspected the prosthesis and found no abnormalities of the stem to explain its incarceration and no iatrogenic perforations in the femur. This case demonstrates a useful technique that should be kept in a revision surgeon's armamentarium for the removal of incarcerated porous ingrowth stems.

Acute and chronic complications of intracortical iliac crest bone grafting versus the traditional corticocancellous technique for spinal fusion surgery.

Although autologous bone graft from the iliac crest is the gold standard for most spinal fusion applications, it is known to cause significant graft-site morbidity. Unlike the traditional corticocancellous allograft, the intracortical method leaves the iliac crest in continuity and decreases the surgical incision and overall area of dissection. We hypothesized this modified technique would decrease pain and complication rate. We first performed an extensive literature review to ascertain which questions, variables, and results were found to be statistically significant regarding the postoperative course and complication rates in patients who underwent iliac crest bone grafting. We then created an Iliac Crest Bone Graft survey that was mailed to 293 patients who had undergone intracortical iliac crest bone graft at our institution to assess postoperative pain and complications.One hundred one (34.5%) surveys were returned. Differences in chronic pain between the surgical types (cervical, lumbosacral, traumatic, and scoliosis) using the intracortical technique showed a trend toward statistical significance (F=2.42, P<.071); this trend was mostly due to no chronic pain reported in the cervical and traumatic groups. Patients experiencing chronic pain at their graft site using the intracortical technique had a statistically significant difference in pain between the same incision versus a separate incision (F=5.05, P<.027), with a separate incision having lower reported pain. After meta-analyses were performed with articles obtained in the literature search using the traditional corticocancellous technique and compared to our results, the only variable that obtained statistical significance was decreased chronic pain at 2 years with the intracortical method in our study (P<.001).

Acetabular revisions using trabecular metal cups and augments.

The purpose of this study is to evaluate the efficacy of trabecular metal (TM) shells and augments in acetabular revisions with significant pelvic bone loss. We retrospectively reviewed 97 cases of consecutive loose total hip arthroplasty with a minimum of Paprosky grade IIA pelvic bone loss treated with a TM revision acetabular component with or without modular augments. The average Harris hip score improved from 55 preoperatively to 76 postoperatively. At the most recent radiographic evaluation, 88 cups demonstrated no lucent lines, 1 cup had lucent lines but remained well fixed, and 8 cups underwent resection arthroplasty for infection. One cup was revised for chronic instability. There were no aseptic failures in this series. Trabecular metal acetabular cups and shells with or without the use of modular augments can be effectively used to revise failed acetabular components in patients with substantial pelvic bone loss.

Obesity and osteoarthritis.

Osteoarthritis (OA) has become one of the leading causes of disability in the United States. Mechanical forces exerted on the joints are a significant cause of OA and one of the most modifiable risk factors. As determined by body mass index (BMI), 34 million US adults are obese, and 13 million of these are morbidly obese. Female sex, lower educational levels, obesity, and poor muscular strength are associated with symptomatic disease and subsequent disability. Recently, genetics has been shown to be a significant factor in the disease process. March and Bagga (Med J Aust. 2004; 180 (5 suppl): S6-S10) showed that the risk for knee OA increased by 36% for every 2 units of BMI (5 kg) of weight gain. Bariatric surgery results in a mean weight loss of 44 kg (97 lb). Eighty-nine percent of patients had complete relief of pain caused by OA in at least one joint after undergoing bariatric surgery.

Clinical applications of oxidized zirconium.

Total joint arthroplasty is being performed in younger, more active patients, which necessitates improved implant longevity and enhanced component performance. Over the past decade, there has been an increased focus on alternative bearing materials as a potential solution to these issues. Historically, cobalt-chromium has been the material of choice as a bearing surface for both the femoral component in total knee arthroplasty (TKA) and the femoral head articulation in total hip arthroplasty (THA). In recent years, oxidized zirconium (OxZr) has been introduced as a bearing surface with superior resistance to surface roughening, improved frictional characteristics, and excellent biocompatibility as compared with cobalt-chrome. This article demonstrates the use of OxZr as an alternate bearing in the setting of TKA, THA, and hip hemi-arthroplasty based on its biomaterial properties as it applies to polyethylene and native cartilage surface articulation.