Natural History of Opioid Use in Naive and Tolerant Patients in Revision Total Hip Arthroplasty.

BACKGROUND: Opioid use after revision total hip arthroplasty (rTHA) has not been well characterized. The purpose of this study was to characterize preoperative, perioperative, and postoperative opioid use during rTHA. METHODS: Patients undergoing revision THA from 2010 to 2018 were screened for opioid use 3 months before revision surgery and tracked 24 months postoperatively. Patients were categorized as naïve or tolerant. Opioid prescriptions and average morphine milligram equivalents (MME) were compared between the two groups. RESULTS: One hundred twenty-four of 247 patients (50%) in the tolerant group averaged a preoperative MME of 23.7 mg/day. Postoperatively, tolerant patients received significantly higher daily MME at all time points, including at 3 months 31.4 versus 18.1 mg/day (P < 0.001), 6 months 19.9 versus 2.95 mg/day (P < 0.001), 12 months 14.3 versus 3.5 mg/day (P < 0.001), and 24 months 10.7 versus 2.17 mg/day (P < 0.001). Tolerant patients were more likely to have a prescription at 6 months (44% versus 22%), 12 months (41.4% versus 24%), and 24 months (38% versus 19.3%) (P < 0.001, P = 0.002, P < 0.001, respectively). DISCUSSION: Opioid-tolerant patients had higher postoperative MME requirements for longer recovery duration. Both groups reduced opioid use at 3 months and plateaued at 6 months. These findings can help the revision surgeon counsel patients and expectations.

Final 24-hour Drain Output and Postoperative Day Are Poor Indicators for Appropriate Drain Removal.

Drains are used in plastic surgery to remove excess fluid while ameliorating complications. However, there is a paucity of evidence supporting guiding parameters on when to discontinue a drain. The aim of our study was to determine whether two of the most common parameters, drain volume 24 hours before removal or postoperative day, are valid indicators for drain removal. Methods: A retrospective chart review was conducted for surgical operations performed by our division between July 2014 and May 2019. Of the 1308 patients, 616 had a drain and a complete record. Demographics, medical history, operative time, antibiotic use, anatomic site, donor/recipient, and complication type were recorded. Complications were defined as events that deviated from expected postoperative course or required pharmacological/procedural intervention. T-test and Chi square were used to analyze data. Results: In total, 544 patients were in the no complication group, and 72 were in the complication group. The complication group patients had drains removed later than patients in the no complication group (15.7 days versus 12.5 days, P = 0.0003) and had similar final 24-hour drain volumes versus patients in the no complication group (16.7 mL versus 18.8 mL, P = 0.2548). The complication group had more operations on the pelvis (11% versus 2.1%; P = 0.000017) or thigh (8.5% versus 3.4%; P = 0.029). Conclusions: Our data suggest neither postoperative day nor 24-hour volume before drain removal are valid indicators for removal. Late removal correlates with more complications; however, persisting output leading to later removal may be predictive of an impending complication rather than delays in drain removal causing the complication.

Effect of Postoperative Oral Antibiotics on Infections and Wound Healing Following Foot and Ankle Surgery.

BACKGROUND: There is controversy regarding the effectiveness of postoperative antibiotics to prevent wound infection. Some surgeons still use a routine postoperative oral antibiotic regimen. The purpose of this study was to review a series of cases and document statistically any difference in infection rates and whether routine postoperative antibiotics in foot and ankle surgery are justified. METHODS: A retrospective chart review of 649 patients was performed who underwent elective foot and ankle surgery. Six hundred thirty-one patient charts were included in the final analysis. Evaluated were patients who did and did not receive postoperative oral antibiotics in order to identify whether a difference in infection rate or wound healing occurred. The study also evaluated risk factors for developing infection following foot and ankle surgery. RESULTS: The number of infections in patients receiving postoperative oral antibiotics was 6 (3%), while the number of infections in those who did not receive postoperative oral antibiotics was 10 (2%) (P = .597). The difference of deep versus superficial infections and delays in wound healing between the 2 groups was not statistically significant. Patients who developed infections were older and had a higher prevalence of hypertension, a history of neoplasm, and a greater American Society of Anesthesiologists Classification of Physical Health. CONCLUSION: This study suggests that routine use of postoperative antibiotics in foot and ankle surgery does not affect wound complications or infection rates. Additionally, patients who are older and those with multiple medical problems may be at higher risk for developing postoperative infection following foot and ankle surgeries. LEVEL OF EVIDENCE: Level III, retrospective comparative series.

Protein kinase A inhibitor proteins (PKIs) divert GPCR-Gαs-cAMP signaling toward EPAC and ERK activation and are involved in tumor growth.

The PKA-inhibitor (PKI) family members PKIα, PKIß, and PKIγ bind with high affinity to PKA and block its kinase activity, modulating the extent, and duration of PKA-mediated signaling events. While PKA is a well-known regulator of physiological and oncogenic events, the role of PKI proteins in these pathways has remained elusive. Here, by measuring activation of the MAPK pathway downstream of GPCR-Gαs-cAMP signaling, we show that the expression levels of PKI proteins can alter the balance of activation of two major cAMP targets: PKA and EPAC. Our results indicate that PKA maintains repressive control over MAPK signaling as well as a negative feedback on cAMP concentration. Overexpression of PKI and its subsequent repression of PKA dysregulates these signaling pathways, resulting in increased intracellular cAMP, and enhanced activation of EPAC and MAPK. We also find that amplifications of PKIA are common in prostate cancer and are associated with reduced progression free survival. Depletion of PKIA in prostate cancer cells leads to reduced migration, increased sensitivity to anoikis and reduced tumor growth. By altering PKA activity PKI can act as a molecular switch, driving GPCR-Gαs-cAMP signaling toward activation of EPAC-RAP1 and MAPK, ultimately modulating tumor growth.

YAP1/TAZ-TEAD transcriptional networks maintain skin homeostasis by regulating cell proliferation and limiting KLF4 activity.

The Hippo TEAD-transcriptional regulators YAP1 and TAZ are central for cell renewal and cancer growth; however, the specific downstream gene networks involved in their activity are not completely understood. Here we introduce TEADi, a genetically encoded inhibitor of the interaction of YAP1 and TAZ with TEAD, as a tool to characterize the transcriptional networks and biological effects regulated by TEAD transcription factors. Blockage of TEAD activity by TEADi in human keratinocytes and mouse skin leads to reduced proliferation and rapid activation of differentiation programs. Analysis of gene networks affected by TEADi and YAP1/TAZ knockdown identifies KLF4 as a central transcriptional node regulated by YAP1/TAZ-TEAD in keratinocyte differentiation. Moreover, we show that TEAD and KLF4 can regulate the activity of each other, indicating that these factors are part of a transcriptional regulatory loop. Our study establishes TEADi as a resource for studying YAP1/TAZ-TEAD dependent effects.

Tissue Factor-Expressing Tumor-Derived Extracellular Vesicles Activate Quiescent Endothelial Cells via Protease-Activated Receptor-1.

Tissue factor (TF)-expressing tumor-derived extracellular vesicles (EVs) can promote metastasis and pre-metastatic niche formation, but the mechanisms by which this occurs remain largely unknown. We hypothesized that generation of activated factor X (FXa) by TF expressed on tumor-derived EV could activate protease-activated receptors (PARs) on non-activated endothelial cells to induce a pro-adhesive and pro-inflammatory phenotype. We obtained EV from TF-expressing breast (MDA-MB-231) and pancreatic (BxPC3 and Capan-1) tumor cell lines. We measured expression of E-selectin and secretion of interleukin-8 (IL-8) in human umbilical vein endothelial cells after exposure to EV and various immunologic and chemical inhibitors of TF, FXa, PAR-1, and PAR-2. After 6 h of exposure to tumor-derived EV (pretreated with factor VIIa and FX) in vitro, endothelial cells upregulated E-selectin expression and secreted IL-8. These changes were decreased with an anti-TF antibody, FXa inhibitors (FPRCK and EGRCK), and PAR-1 antagonist (E5555), demonstrating that FXa generated by TF-expressing tumor-derived EV was signaling through endothelial PAR-1. Due to weak constitutive PAR-2 expression, these endothelial responses were not induced by a PAR-2 agonist peptide (SLIGKV) and were not inhibited by a PAR-2 antagonist (FSLLRY) after exposure to tumor-derived EV. In conclusion, we found that TF-expressing cancer-derived EVs activate quiescent endothelial cells, upregulating E-selectin and inducing IL-8 secretion through generation of FXa and cleavage of PAR-1. Conversion of resting endothelial cells to an activated phenotype by TF-expressing cancer-derived EV could promote cancer metastases.