Impact of Accountable Care Organizations on Utilization, Care, and Outcomes: A Systematic Review.

Since 2010, more than 900 accountable care organizations (ACOs) have formed payment contracts with public and private insurers in the United States; however, there has not been a systematic evaluation of the evidence studying impacts of ACOs on care and outcomes across payer types. This review evaluates the quality of evidence regarding the association of public and private ACOs with health service use, processes, and outcomes of care. The 42 articles identified studied ACO contracts with Medicare ( N = 24 articles), Medicaid ( N = 5), commercial ( N = 11), and all payers ( N = 2). The most consistent associations between ACO implementation and outcomes across payer types were reduced inpatient use, reduced emergency department visits, and improved measures of preventive care and chronic disease management. The seven studies evaluating patient experience or clinical outcomes of care showed no evidence that ACOs worsen outcomes of care; however, the impact on patient care and outcomes should continue to be monitored.

Incidence and predictors of axillary metastasis in T1 carcinoma of the breast.

BACKGROUND: The relatively low incidence (6 to 31 percent) of axillary metastasis in patients with T1 carcinoma of the breast (20 mm or smaller) has led some surgeons to question routine axillary lymphadenectomy (ALND) for patients with no palpable axillary metastases and T1 tumors. This study was undertaken to determine the incidence and predictors of axillary lymph node metastasis in patients with T1 carcinoma of the breast and evaluate the role of sentinel lymphadenectomy (SLND) in this context. STUDY DESIGN: All patients with T1 invasive carcinoma of the breast treated at the John Wayne Cancer Institute between January 1988 and June 1994 were prospectively studied. The study population was comprised of 259 women who had ALND. Of these patients, 114 were part of a pilot study examining the efficacy of SLND. RESULTS: Of the 259 women, 69 (27 percent) had axillary metastasis. Hematoxylin and eosin staining identified nodal involvement in 13 percent of patients with T1a and T1b tumors (10 mm or less) and in 30 percent of patients with T1c tumors (p = 0.002). Other factors such as age, hormone receptor status, presence of ductal carcinoma in situ, histology, ploidy, and S-phase were not significant predictors of involvement. A sentinel node was identified in 73 patients: this node accurately predicted axillary status in 72 patients, was the only positive node in nine of 16 patients with axillary involvement, and was 100 percent predictive of axillary status when the primary tumor was 10 mm or less. Retrospective immunohistochemical staining revealed an additional seven patients with positive sentinel nodes. With this technique, even T1a lesions had a 15 percent incidence of axillary metastasis. CONCLUSIONS: Tumor size is the only accurate predictor of axillary metastasis in patients with T1 carcinoma of the breast. The significant incidence of axillary involvement from T1 tumors mandates accurate staging, even when the tumor is 10 mm or less in size. Examination of a sentinel lymph node may accurately predict axillary metastasis.

Margin status and local recurrence after breast-conserving surgery.

OBJECTIVE: To examine the effect of microscopic tumor at the margins on local recurrence after breast-conserving surgery for invasive carcinoma. DESIGN: Retrospective review of patients treated with surgical resection followed by radiation therapy. SETTING: A university-based radiation department and a community-based cancer referral center. PATIENTS: A consecutive series of 272 women treated between 1982 and 1990. MAIN OUTCOME MEASURE: Local recurrence according to the histopathologic status of excised margins and the total dose of radiation. RESULTS: During a mean follow-up period of 48 months, the overall rate of local recurrence was 6.3%. Local recurrence was more frequent (P = .0001) in patients with histologically positive margins (18.2%) than in those with unknown margins (7.1%) or negative margins (3.7%). In the 44 patients with positive margins, the local recurrence rate was 8.3% after radiation doses of 66 Gy or more compared with 21.9% following lower doses. CONCLUSIONS: Microscopic involvement of resection margins increases the risk of local recurrence following breast-conserving surgery for invasive carcinoma. Therefore, every effort should be made to achieve negative margins intraoperatively.

Depressed neutrophil chemotaxis in children suffering blunt trauma.

OBJECTIVE: Impaired neutrophil (PMN) function, due in part to release of immature PMNs into the circulation, contributes to the increased rate of infection observed in adults suffering blunt trauma. The objective of this study was to determine whether similar events occur in children. METHODS: We assessed PMN chemotaxis and PMN maturation in 25 children (7 young children and 18 adolescents) and 25 adults 1 to 9 days after suffering blunt trauma, and in healthy adult control subjects. PMN chemotaxis was determined using a standard micropore filter assay, whereas PMN maturation was determined with 31D8, a novel monoclonal antibody that binds to mature PMNs more avidly than immature PMNs and band forms. RESULTS: In patients suffering blunt trauma, mean PMN chemotactic values were similar among children (44.6 +/- 2.3 microns) and adults (41.3 +/- 2.1 microns) and both were significantly less than among healthy adults (53.5 +/- 2.4 microns, P < .0005). PMN chemotactic values increased significantly in the 9 days after trauma for both children and adults (F = 13.8, df = 1, P < .0002). Mean PMN 31D8 binding among children with trauma (92.5 +/- 5.2) was significantly less than among healthy adults (117.6 +/- 5.4, P < .0009). CONCLUSIONS: Impairment in PMN chemotaxis occurs in children after blunt trauma and is due in part to release of immature PMNs into the circulation.

Brain death in infants: sensitivity and specificity of current criteria.

Guidelines for the determination of brain death in children were recently published by a multidisciplinary task force. We report a 3-month-old female who fulfilled these criteria but regained partial cortical and brainstem function for a prolonged period. This patient and similar newborn patients are analyzed with respect to sensitivity and specificity of the suggested criteria. Caution is recommended in assuming irreversibility of absent cerebral function in young infants, even beyond the neonatal period.

Two methods for determination of renin secretion rates in rats.

1. Renin secretion rates in normal rats were determined with two different methods: (a) the product of renal plasma flow as measured by sodium p-aminohippurate and the difference between renal and peripheral vein renin activity; (b) the product of this latter difference and the renal plasma flow as calculated from the clearance and extraction of inulin. 2. The renin secretion rates, as calculated by these two methods, were not significantly different (P greater than 0-1) and were found to be highly correlated (r = 0-943; P less than 0-001).