Daniel B. Loriaux

Nanotechnology-based strategies for combating toxicity and resistance in melanoma therapy

Drug toxicity and resistance remain formidable challenges in cancer treatment and represent an area of increasing attention in the case of melanoma. Nanotechnology represents a paradigm-shifting field with the potential to mitigate drug resistance while improving drug delivery and minimizing toxicity. Recent clinical and pre-clinical studies have demonstrated how a diverse array of nanoparticles may be harnessed to circumvent known mechanisms of drug resistance in melanoma to improve therapeutic efficacy. In this review, we discuss known mechanisms of resistance to various melanoma therapies and possible nanotechnology-based strategies that could be used to overcome these barriers and improve the pharmacologic arsenal available to combat advanced stage melanoma.

Risk Assessment And Characterization of 30-Day Perioperative Myocardial Infarction Following Spine Surgery: A Retrospective Analysis of 1346 Consecutive Adult Patients.

Study Design. A retrospective review. Objective. The aim of the study was to perform a risk assessment of 30-day perioperative myocardial infarction (MI) for spine surgery patients. Summary of Background Data. There is an increased emphasis to reduce complications and improve outcomes after spinal surgery. One of the more devastating perioperative complications of spinal surgery is MI. Methods. We evaluated all medical records of 1346 consecutive patients who underwent spinal surgery at a single institution from 2008 to 2010 for incidence of MI within 30 days of surgery and documented all demographic, preoperative, and operative variables. Associations between postoperative MI and individual risk factors were determined using logistic regression analysis. Patients were stratified into emergent and elective groups and a similar analysis was performed. Results. Overall, 22 patients (1.6%) had 30-day perioperative MI, 14 patients (1.2%) undergoing elective surgery, and 8 patients (4.2%) after emergent surgery (P = 0.047). Three (13.6%) patients experienced 30-day mortality and an additional 3 (13.6%) patients experienced mortality within 1 year. Multivariate logistic regression determined that age more than 65 years, atrial fibrillation, hypertension, prior MI, anticoagulant use, low albumin, length of stay more than 7 days, intraoperative transfusion, trauma etiology, baseline creatinine more than 1 mg/dL, and at least 2 levels of spinal fusion were predictive of postoperative MI. For patients undergoing emergent surgery, age more than 65 years was associated with an increased risk of postoperative MI. When stratified by elective surgery, we found that age more than 65, postoperative stay more than 7 days, intraoperative blood transfusion, baseline creatinine more than 1 mg/dL, and fusion of more than 1 level were associated with an increased risk of MI. Conclusion. The present study demonstrates a low incidence of MI after elective surgery with a higher incidence after emergent spine surgery and identifies patient factors predictive of postoperative MI. Level of Evidence: 3

315 Race as a Predictor of Postoperative Hospital Readmission After Spine Surgery.

INTRODUCTION Hospital readmission after surgery results in a substantial economic burden, and several recent studies have investigated the impact of race and ethnicity on hospital readmission rates, with the goal to identify hospitals and patients with high readmission risk. METHODS This single-institution, retrospective cohort study assesses the impact of race, along with preoperative and intraoperative risk factors, on 30-day readmission rates following spinal surgery. A total of 1346 consecutive adult patients who underwent anterior and/or posterior spinal surgery from 2008 to 2010 for degenerative and deformity causes, as well as for higher-risk causes, including traumatic and neoplastic etiologies, were included in the study. Clinical variables included age, demographics, surgical etiology, intraoperative technique, and other comorbidities known to be associated with postoperative complication. RESULTS A total of 1346 patients (654 male, 692 female) were included in the study. With the use of multivariate logistic regression, black patients were found to have over twice the odds of readmission (odds ratio [OR], 2.20; 95% confidence interval [CI],: 1.04-4.64), and patients with total length of stay of 7 or more days had nearly 5 times the odds of readmission (OR, 4.73; 95% CI, 1.72-12.98). Conversely, patients who underwent cervical surgery were found to have lower odds of readmission (OR, 0.27; 95% CI, 0.08-0.91). CONCLUSION Within the context of the ongoing national goal of reducing hospital readmission, our study demonstrated that race and length of hospital stay influence the incidence of 30-day readmission rates after spinal surgery. Studies such as ours will aid in identifying patients with postoperative readmission risk and help elucidate the underlying factors that may be contributing to disparities in readmission after surgery.

Race as a predictor of postoperative hospital readmission after spine surgery

Hospital readmission after surgery results in a substantial economic burden, and several recent studies have investigated the impact of race and ethnicity on hospital readmission rates, with the goal to identify hospitals and patients with high readmission risk. This single-institution, retrospective cohort study assesses the impact of race, along with other risk factors, on 30-day readmission rates following spinal surgery. This study is a single-institution retrospective cohort study with accrual from January 1, 2008, to December 31, 2010. Inclusion criteria included adult patients who underwent anterior and/or posterior spinal surgery. The primary aim of this study was to assess the impact of patient race and other risk factors for postoperative hospital readmission within 30days following spine surgery. A total of 1346 patients (654 male, 692 female) were included in the study. Overall, 159 patients (11.8%) were readmitted in the 30days following their surgery. Multivariate logistic regression found significant risk factors for 30-day readmission, including Black race (OR: 2.20, C.I. 95% (1.04, 4.64)) and total length of stay greater than 7days (OR: 4.73, C.I. 95% (1.72, 12.98)). Cervical surgery was associated with decreased odds of readmission (OR: 0.27, C.I. 95% (0.08, 0.91)). Our study demonstrates that race and length of hospital stay influence the incidence of 30-day readmission rates after spinal surgery. Studies such as ours will aid in identifying patients with postoperative readmission risk and help elucidate the underlying factors that may be contributing to disparities in readmission after surgery.

Independent predictors of mortality following spine surgery.

We investigated the effect of preoperative patient demographics and operative factors on mortality in the 30day postoperative period after spine surgery. Postoperative mortality from surgical interventions has significantly decreased with progressive improvement in surgical techniques and patient selection. Well-studied preoperative risk factors include age, obesity, emphysema, clotting disorders, renal failure, and cardiovascular disease. However, the prognostic implications of such risk factors after spine surgery specifically remain unknown. The medical records of all consecutive patients undergoing spine surgery from 2008-2010 at our institution were reviewed. Patient demographics, comorbidities, indication for operation, surgical details, postoperative complications, and mortalities were collected. The association between preoperative demographics or surgical details and postoperative mortality was assessed via logistic regression analysis. All 1344 consecutive patients (1153 elective, 191 emergency) met inclusion criteria for the study; 19 (1.4%) patients died in the 30days following surgery. Multivariable logistic regression found several predictive factors of mortality for all spine surgery patients: operation in the cervical area (odds ratio [OR]: 7.279, 95% confidence interval [CI]: 1.37-42.83, p=0.02), postoperative sepsis (OR: 5.75, 95% CI: 1.16-26.38, p=0.03), operation for neoplastic (OR: 7.68, 95% CI: 1.53-42.71, p=0.01) or traumatic (OR: 13.76, 95% CI: 2.40-88.68, p=0.03) etiology, and age as defined as a continuous variable (OR: 1.05, 95% CI: 1.01-1.10, p=0.03). This study demonstrates predictive factors to help identify and evaluate patients who are at higher risk for mortality from spinal surgery, and potentially devise methods to reduce this risk.

Image-guided percutaneous internal fixation of sacral fracture

Percutaneous iliosacral screw placement is a technically challenging procedure with a significant complication profile for misplaced screws. The use of stereotactic image guidance has been shown to provide superior accuracy in the placement of spinal instrumentation. Here, the authors describe a novel application of O-arm technology (Medtronic Sofamor Danek, Memphis, TN, USA) to help safely place iliosacral screws for the treatment of a traumatic sacral fracture.

Traumatic atlanto-occipital dissociation presenting as locked-in syndrome

We present an unusual presentation of unstable atlanto-occipital dissociation as locked-in syndrome. Traumatic atlanto-occipital dissociation is a severe injury that accounts for 15-20% of all fatal cervical spinal injuries. A disruption occurs between the tectorial ligaments connecting the occipital condyle to the superior articulating facets of the atlas, resulting in anterior, longitudinal, or posterior translation, and it may be associated with Type III odontoid fractures. Furthermore, the dissociation may be complete (atlanto-occipital dislocation) or incomplete (atlanto-occipital subluxation), with neurologic findings ranging from normal to complete quadriplegia with respiratory compromise.

Inferior Vena Cava Filter Thrombosis in the Postoperative Neurosurgical Setting: Case Report and Review of the Literature.

There are no definitive treatment guidelines for caval-filter thrombosis in the postoperative setting. Clinical management for partial or complete postoperative inferior vena cava (IVC) occlusion relies solely on expert opinion, anecdotal evidence, and small clinical trials. As such, the primary objective of the present report is to offer a complex case of extensive IVC filter occlusion in a neurosurgical patient with past medical history significant for protein C deficiency. The presentation, unique radiological findings, management, and outcome will be discussed. No similar cases of massive IVC-occlusive disease in a thrombophilic patient early in the postoperative course following neurosurgical intervention are documented in the medical literature.