Daring discourse: should acute pain medicine be a stand-alone service?

Acute pain medicine (APM) has been incorporated into healthcare systems in varied manners with some practices implementing a stand-alone acute pain service (APS) staffed by consultants who are not simultaneously providing care in the operating room (OR). In contrast, other practices have developed a concurrent OR-APS model where there is no independent team beyond the intraoperative care providers. There are theoretical advantages of each approach primarily with respect to patient outcomes and financial cost, and there is little evidence to instruct best practice. In this daring discourse, we present two opposing perspectives on whether or not APM should be a stand-alone service. While evidence to guide best practice is limited, our goal is to encourage discussion of the varied APS practice models and research into their impact on outcomes and costs.

Indications for inferior vena cava filter placement: do physicians comply with guidelines?

PURPOSE: Inferior vena cava (IVC) filter placement has increased significantly over the past few decades, but indications for filter placement vary widely depending on which professional society recommendations are followed, and it is uncertain how compliant physicians are in adhering to guidelines. This study assessed documented indications for IVC filter placement and evaluated compliance with standards set by the American College of Chest Physicians (ACCP) and the Society of Interventional Radiology (SIR). MATERIALS AND METHODS: A single-center, retrospective medical record review in a metropolitan, 652-bed, acute care, teaching hospital. Inpatient filter placement over a 26-month period was reviewed. The study measured compliance with established guidelines, relationship of medical specialty to filter placement, and evaluation of self-referral patterns among physicians. RESULTS: Compliance with established ACCP guidelines was poor regardless of whether the IVC filter insertion was performed by interventional radiology (IR; 43.5%), vascular surgery (VS; 39.9%), or interventional cardiology (IC; 33.3%) staff. Compliance with the less restrictive SIR guidelines was better (77.5%, 77.1%, and 80% for IR, VS, and IC, respectively). There was a greater degree of guideline compliance when filter placement was recommended by internal medicine (IM)-trained physicians than by non-IM-trained physicians: 46.3% of IR-placed filters requested by IM physicians met ACCP criteria whereas only 24.0% of filters recommended by non-IM specialties were compliant with criteria (P = .03). In the VS group, these compliance rates were 45.8% and 31.5%, respectively (P = .03). Among IR-placed filters, 84.0% of IM-recommended filter placements were compliant with SIR guidelines, versus only 48.0% of non-IM-recommended placements (P ≤ .001). In the VS group, these compliance rates were 87.8% and 69.6%, respectively (P ≤ .001). CONCLUSIONS: There is poor physician compliance with guidelines for IVC filter placement. Most filter indications meeting SIR guidelines are for patients classified as "falls risks," failures of anticoagulation, patients with limited cardiopulmonary reserve and patients non compliant with anticoagulation medications. This single-center study suggests a need for harmonization of current guidelines espoused by professional societies.

Identification of an evolutionarily conserved transcriptional signature of CD8 memory differentiation that is shared by T and B cells.

After Ag encounter, naive lymphocytes differentiate into populations of memory cells that share a common set of functions including faster response to Ag re-exposure and the ability to self-renew. However, memory lymphocytes in different lymphocyte lineages are functionally and phenotypically diverse. It is not known whether discrete populations of T and B cells use similar transcriptional programs during differentiation into the memory state. We used cross-species genomic analysis to examine the pattern of genes up-regulated during the differentiation of naive lymphocytes into memory cells in multiple populations of human CD4, CD8, and B cell lymphocytes as well as two mouse models of memory development. We identified and validated a signature of genes that was up-regulated in memory cells compared with naive cells in both human and mouse CD8 memory differentiation, suggesting marked evolutionary conservation of this transcriptional program. Surprisingly, this conserved CD8 differentiation signature was also up-regulated during memory differentiation in CD4 and B cell lineages. To validate the biologic significance of this signature, we showed that alterations in this signature of genes could distinguish between functional and exhausted CD8 T cells from a mouse model of chronic viral infection. Finally, we generated genome-wide microarray data from tetramer-sorted human T cells and showed profound differences in this differentiation signature between T cells specific for HIV and those specific for influenza. Thus, our data suggest that in addition to lineage-specific differentiation programs, T and B lymphocytes use a common transcriptional program during memory development that is disrupted in chronic viral infection.

Antigen-specific T-cell memory is preserved in children treated for acute lymphoblastic leukemia.

Despite profound T-cell immunodeficiency, most patients treated with chemotherapy do not succumb to infection. The basis for residual protective immunity in lymphopenic patients is not known. We prospectively measured T-cell numbers, thymopoiesis, and T-cell memory in 73 children undergoing a 2-year chemotherapy regimen for acute lymphoblastic leukemia (ALL) and compared them to an age-matched cohort of 805 healthy children. Most patients had profound defects in CD4 and CD8 T-cell numbers at diagnosis that did not recover during the 2 years of therapy. Thymic output and the fraction of naive T cells were significantly lower than in healthy controls. However, the remaining T-cell compartment was enriched for antigen-experienced, memory T cells defined both by phenotype and by function. This relative sparing of T-cell memory may, in part, account for the maintenance of protective immunity in lymphopenic patients treated for ALL. Moreover, because the memory T-cell compartment is least affected by ALL and its treatment, strategies to induce immunity to pathogens or tumor antigens in cancer patients may be most successful if they seek to expand pre-existing memory T cells.