[Clinical characteristics of patients referred to cardio-oncology clinic].

To explore characteristics of outpatients in a single cardio-oncology clinic, patients visiting cardio-oncology clinic of Fuwai Hospital CAMS&PUMC (Beijing, China) from January 2020 to December 2021 were analyzed retrospectively. In total, 330 patients were included, the median age (Q1, Q3) was 58(46, 66) years, and there were 192 females (58.2%). The purposes for visit included an evaluation and treatment of cardiovascular adverse reactions (n=247, 74.8%), pre-antitumor therapy assessment (n=51, 15.5%), and management of primary or metastatic cardiac tumors (n=32, 9.7%). For patients with cardiovascular adverse reactions, the most common tumor type was breast cancer (n=88, 29.5%), followed by gastrointestinal cancer (n=70, 23.5%), and hematological cancers (n=62, 20.8%). Among them, 236 cases (95.5%) had received antitumor drugs in the past; 38 cases (15.4%) had a history of chest radiotherapy; some cases were complicated with hypertension (n=69, 23.2%) and/or hyperlipidemia (n=69, 23.2%); 42 cases (14.1%) had a history of coronary heart disease; and 16 cases (5.4%) were complicated with atrial fibrillation or flutter. Among 32 patients with cardiac tumors, 11 cases (34.4%) had primary malignant tumors; 6 cases (18.8%) had benign tumors; 2 cases (6.3%) had metastatic tumors; and 13 (40.6%) had unknown pathological types. This study explores the epidemiology of cardio-oncology in China and provides clinical insights for the future development of cardio-oncology. In the future, it is still necessary to study the benefits of cardio-oncology clinics and develop standardized indicators to evaluate their benefits.

Effects of a Pragmatic Home-based Exercise Program Concurrent With Neoadjuvant Therapy on Physical Function of Patients With Pancreatic Cancer: The PancFit Randomized Clinical Trial.

OBJECTIVE: To determine the effects of a preoperative, home-based exercise program on fitness and physical function in patients with pancreatic cancer. BACKGROUND: We previously established a well-tolerated preoperative exercise program after finding a high frequency of sarcopenia and frailty in patients with pancreatic cancer. METHODS: In this randomized, controlled trial (NCT03187951), patients with pancreatic cancer were randomized to Arm A: enhanced usual care or Arm B: prescribed aerobic and resistance exercise during neoadjuvant therapy. Patients received nutrition counseling and activity trackers. The primary endpoint was a 6-minute walk distance (6MWD; ≥14 meters improvement was clinically meaningful). Secondary endpoints included additional physical function tests, health-related quality of life, and clinical outcomes. RESULTS: One hundred fifty-one patients were randomized. Objectively measured weekly activity (153.2±135.6 and 159.8±122.8 min in Arm A and B, respectively, P =0.62) and self-reported weekly moderate-to-strenuous physical activity (107.4±160.4 and 129.6±161.6 min in Arm A and Arm B, respectively, P =0.49) were similar, but weekly strength training sessions increased more in Arm B (by 1.8±1.8 vs 0.1±2.4 sessions, P <0.001). 6MWD improved in both Arm A (mean change 18.6±56.8 m, P =0.01) and Arm B (27.3±68.1 m, P =0.002). Quality of life and clinical outcomes did not significantly differ between arms. Pooling patients in both study groups, exercise, and physical activity was favorably associated with physical performance and clinical outcomes. CONCLUSIONS: In this randomized trial of prescribed exercise versus enhanced usual care during neoadjuvant therapy for pancreatic cancer, a high volume of physical activity and increased exercise capacity were observed in both arms, highlighting the importance of activity among patients preparing for surgery.

Frequency and reasons for unplanned transfer to the primary acute care service of inpatient rehabilitation glioblastoma multiforme patients.

PURPOSE: To determine the percentage of and factors associated with unplanned transfer to the acute care service of glioblastoma multiforme acute rehabilitation inpatients. METHODS: Retrospective review of glioblastoma multiforme acute rehabilitation inpatients admitted 4/1/2016-3/31/2020 at a National Cancer Institute Comprehensive Cancer Center. RESULTS: One hundred thirty-nine consecutive admissions of unique glioblastoma multiforme acute rehabilitation inpatients were analyzed. Fifteen patients (10.7%, 95% confidence interval 6.5-17.1%) were transferred to the acute care service for unplanned reasons. The most common reasons for transfer back were neurosurgical complication 6/15(40%), neurologic decline due to mass effect 4/15(26.7%), and pulmonary embolism 2/15(13.3%). Older age (p = 0.010), infection prior to acute inpatient rehabilitation transfer (p = 0.020), and lower activity measure of post-acute care 6-click basic mobility scores (p = 0.048) were significantly associated with transfer to the acute care service. Patients who transferred to the acute care service had significantly lower overall survival than patients who did not transfer off (log-rank test p = 0.001). CONCLUSION: Acute inpatient physiatrists should closely monitor patients for neurosurgical and neurologic complications. The variables significantly associated with transfer to the acute care service may help identify patients at increased risk for medical complications who may require closer observation.

Variation of Benzo[a]pyrene, NNN, and NNK Levels in 16 Commercial Smokeless Tobacco Products.

This study examined the variation of benzo[a]pyrene (B[a]P), N'-nitrosonornicotine (NNN), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) levels in 16 smokeless tobacco products from several different product subcategories obtained at two different locations and at two different procurement times. B[a]P quantities range from 0.6 to 160 ng/g on a wet-weight basis, whereas NNN and NNK quantities range from 276 to 10473 ng/g and 79 to 28882 ng/g, respectively. The B[a]P, NNN, and NNK quantities vary widely among various smokeless tobacco product categories and among various brands within each product subcategory. Dry snuff products contain the highest B[a]P, NNN, and NNK quantities, whereas loose and portioned snus products contain the lowest B[a]P, NNN, and NNK levels. In general, variation of B[a]P, NNN, and NNK levels across four sets of each product brand purchased six months apart and at two different locations show statistically significant differences (p < 0.05), although with a much narrower product set-to-set variability.

Quantitative measurement of harmful and potentially harmful constituents, pH, and moisture content in 16 commercial smokeless tobacco products.

Smokeless tobacco products expose adult and youth tobacco users to various addictive and carcinogenic constituents that can cause long-term nicotine dependence and oral cancers. In this study, nicotine, benzo[a]pyrene (B[a]P), N'-nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), acetaldehyde, crotonaldehyde, formaldehyde, moisture, and pH levels in 16 smokeless tobacco products were measured on a wet-weight basis (wwb). In addition, change in analytical variability with increasing replicate measurements was assessed. Total nicotine in the products varied from 6.2 to 35.5 mg/g. The percentage of total nicotine in the unprotonated form ranged from 0.1 to 62%; whereas, product moisture varied from 7.4 to 57%. The quantities of harmful and potentially harmful constituents (HPHCs) range from 0.46 to 179.9 ng/g for B [a]P, 270-12206 and 81-20716 ng/g for NNN and NNK, respectively, and 0.33-6.85 and 0.13-5.67 µg/g for acetaldehyde and formaldehyde, respectively. This study shows wide variation in smokeless tobacco product HPHC quantities. The results also show that analytical variability stabilizes after seven replicate measurements.

[Can periodontitis affect colorectal cancer by altering microbiota balance?]

Emerging evidence suggests that, along with dietary, genetic and environmental factors, gut microbiota plays a role in the progress of colorectal cancer. Dysbiosis of oral flora in patients with periodontitis affects the composition of microbial community in the gut, impairs gut barrier function, and induces a proinflammatory microenvironment, all of which contribute to the progression of colorectal cancer. In view of the influences by microbiota dysbiosis, this article reviews the role of periodontitis in affecting the occurrence and development of colorectal cancer.

Aprotic Solvent Exposes an Altered Mechanism for Copper-Catalyzed Ethylene Electrosynthesis.

The selectivity and efficiency of Cu-catalyzed CO2 or CO electroreduction are known to be sensitive to the electrolyte composition. However, in aqueous media, changes to pH and ionic composition do not alter the electrokinetic profile of C2 product formation, commonly invoked to proceed via a rate-limiting pH-independent C-C coupling step to form an oxyanionic *CO dimer. We hypothesize that new mechanistic pathways can be exposed in an aprotic solvent-based electrolyte, where inhibited interfacial charge stabilization can favor pathways with electroneutral intermediates resulting from proton-coupled electron-transfer (PCET) steps from an exogenous donor. We herein report CO electroreduction to higher-order products on a polycrystalline Cu catalyst with dimethyl sulfoxide as the solvent and phenol as the proton donor. CO is reduced principally to C2 products including ethylene, acetate, ethylene glycol, and ethane with negligible methane production. In stark contrast to aqueous electrolytes, we observe a low Tafel slope (27 ± 1 mV dec-1) and Nernstian dependence on proton activity for ethylene formation, suggesting a dramatically different mechanism involving quasi-equilibrated PCET steps. This work highlights the critical role of the solvent environment and proton donor in dictating the mechanistic landscape of CO electroreduction, exposing new strategies for tuning product selectivity in hydrocarbon electrosynthesis.

[Progress in treatment for malignant pleural mesothelioma].

Malignant pleural mesothelioma (MPM) is a kind of invasive malignant tumor originated from pleural tissue. The incidence of MPM is not high in the population, but the prognosis is very poor. The median survival time is only about 12 months. Pemetrexed combined with platinum is the first-line chemotherapy regimen recommended by the current guidelines. The use of bevacizumab will further prolong the survival of chemotherapy. Once resistance happened, no anti-tumor treatment has been confirmed to achieve survival benefits. Therefore, there is no recommended standard second-line MPM regimen in international and domestic guidelines, including National Comprehensive Cancer Network (NCCN) guidelines. Vinorelbine, gemcitabine and other monotherapy regimens are commonly used in clinical practice, but the median progression free survival (PFS) is only about 3 months. Immune checkpoint inhibitors (ICIS) have been proved to have a significant inhibitory effect on tumor growth in a variety of malignant tumors, and their efficacy is related to the expression of programmed death-ligand 1(PD-L1). In unresectable MPM, programmed death 1 (PD-1)/PD-L1 inhibitors have been used in a series of clinical studies in the first-line, second-line and above treatment. Some of the results have been cited and recommended by international guidelines, but the overall efficacy improvement is still limited. This review summarizes the latest clinical studies and researches in the field of MPM treatment and predicts the directions and prospect of improving the therapeutic effect in the future.

Genomic and transcriptomic profiling reveals distinct molecular subsets associated with outcomes in mantle cell lymphoma.

Mantle cell lymphoma (MCL) is a phenotypically and genetically heterogeneous malignancy in which the genetic alterations determining clinical indications are not fully understood. Here, we performed a comprehensive whole-exome sequencing analysis of 152 primary samples derived from 134 MCL patients, including longitudinal samples from 16 patients and matched RNA-Seq data from 48 samples. We classified MCL into 4 robust clusters (C1-C4). C1 featured mutated immunoglobulin heavy variable (IGHV), CCND1 mutation, amp(11q13), and active B cell receptor (BCR) signaling. C2 was enriched with del(11q)/ATM mutations and upregulation of NF-κB and DNA repair pathways. C3 was characterized by mutations in SP140, NOTCH1, and NSD2, with downregulation of BCR signaling and MYC targets. C4 harbored del(17p)/TP53 mutations, del(13q), and del(9p), and active MYC pathway and hyperproliferation signatures. Patients in these 4 clusters had distinct outcomes (5-year overall survival [OS] rates for C1-C4 were 100%, 56.7%, 48.7%, and 14.2%, respectively). We also inferred the temporal order of genetic events and studied clonal evolution of 16 patients before treatment and at progression/relapse. Eleven of these samples showed drastic clonal evolution that was associated with inferior survival, while the other samples showed modest or no evolution. Our study thus identifies genetic subsets that clinically define this malignancy and delineates clonal evolution patterns and their impact on clinical outcomes.

Volatile Organic Compounds in Mainstream Smoke of Sixty Domestic Little Cigar Products.

The mainstream smoke yields of five volatile organic compounds (VOCs) were determined from 60 commercial U.S. little cigar products under ISO 3308 and Canadian Intense (CI) smoking regimens on linear smoking machines using a gas sampling bag collection. The five VOCs, 1,3-butadiene, acrylonitrile, benzene, isoprene, and toluene were analyzed using an automated GC/MS analytical method validated for measuring various VOCs in mainstream smoke. The VOCs range in amounts from micrograms to milligrams per little cigar. VOC deliveries vary considerably among the little cigar products under the ISO smoking regimen primarily due to varying filter ventilation. Under the CI smoking regimen where filter ventilation is blocked, the delivery range narrows, although individual and total VOC yields are approximately 2 fold higher than those under the ISO smoking regimen. Correlation analysis reveals strong associations between acrylonitrile and 1,3-butadiene or toluene under the ISO smoking regimen. Compared to cigarettes, little cigars delivered substantially higher VOC mainstream smoke yields under both ISO and CI smoking regimens. Moreover, little cigar smoke also contains higher VOCs than cigarette smoke when adjusted for mass of tobacco.

Surgical Repair of Congenital Diaphragmatic Hernia After Extracorporeal Membrane Oxygenation Cannulation: Early Repair Improves Survival.

OBJECTIVE: To determine the optimal timing of congenital diaphragmatic hernia (CDH) repair after extracorporeal membrane oxygenation (ECMO) cannulation. SUMMARY BACKGROUND DATA: The timing of CDH repair after ECMO cannulation remains a controversial topic due to studies with low power or strong selection bias. METHODS: This is a 2-aim retrospective cohort study based on the CDH Study Group registry for the period of 2007-2017. Aim 1-Compare On versus After ECMO repair. Aim 2-Compare Early versus Late repair on ECMO. In order to minimize selection bias and account for non-repairs, subjects in each aim were stratified into study groups based on their treatment center's characteristics. In each aim, the study groups were matched based on propensity score (PS). The main outcomes included mortality rate and incidence of non-repair. RESULTS: In aim 1, 136 patients remained in each group after PS matching. Compared to the After ECMO group, patients in the On ECMO group demonstrated a lower mortality rate, hazard ratio (HR) 0.54 (0.38, 0.77) (P < 0.001), and lower incidence of non-repair, 5.9% versus 33.8% (P < 0.001). In aim 2, 77 patients remained in each group after PS matching. Compared to the Late group, Early repair of CDH on ECMO was associated with a lower mortality rate, HR 0.51 (0.33, 0.77) (P = 0.002), and lower incidence of non-repair, 9.1% versus 44.2% (P < 0.001). CONCLUSIONS: The approach of early repair after ECMO cannulation is associated with improved survival compared to delayed surgical correction.

Prognostic impact of anatomical extent of metastatic lymph node on gastric cancer: a propensity score matching study.

PURPOSE: Current gastric cancer staging systems overlook the anatomic extent of metastatic lymph nodes (AEMLNs). This study aimed to analyze the prognostic impact of AEMLNs on gastric cancer (GC). METHODS: GC patients with metastatic lymph nodes (MLNs) undergoing curative surgery were retrospectively reviewed and assigned to perigastric (MLNs in station 1-6, PG) and extraperigastric group (7-12, with or without MLNs in PG area, EPG). Overall survival (OS), disease-free survival (DFS) and recurrence patterns were compared before and after 1:1 propensity score matching (PSM). RESULTS: 662 patients were enrolled, 341 (51.5%) and 321 (48.5%) of whom were in the PG and EPG, respectively. After PSM (n = 195), EPG showed poorer 5-year OS (43.4% vs 54.5%, p = 0.014) and DFS (65.0% vs 73.4%, p = 0.068) than PG. EPG had higher incidence of peritoneal recurrence (PR) than PG (19.4% vs 7.4%, p = 0.002). Multivariate analysis identified AEMLNs as prognostic factor for OS [HR = 1.409, 95% confidence interval (CI) 1.062-1.868), DFS (HR = 1.600, 95% CI 1.059-2.416) and PR (HR = 3.708, 95% CI 1.685-8.160). CONCLUSIONS: The anatomic extent of metastatic lymph nodes has an independent prognostic role for GC. Including this element may improve the accuracy of current staging systems.

Immunotherapy-related skeletal muscle weakness in cancer patients: a case series.

Immunotherapy has become a lifeline in cancer treatment. However, increasingly reports of programmed death-1 (PD-1) inhibitors have been linked to autoimmune disorders. We highlight two unique cases that presented with skeletal weakness and resulted in fatalities after developing de novo myasthenia gravis and myositis associated to immunotherapy treatment. Additionally, we describe the importance of early symptoms recognition and prompt treatment in preventing prolonged functional impairments and decreasing associated mortality. Patient 1: a 65-year-old male with a history of metastatic clear cell Renal Cell Cancer with metastasis to the lungs presented with unusual neck weakness, double vision, trouble breathing, and symptoms of urinary incontinence after his 4th cycle of nivolumab (480 mg every 4 weeks). He had a positive fatigability test, diplopia, and proximal weakness in bilateral upper extremities with an abnormal negative inspiratory force (NIF). Patient 2: a 83-year-old male with history of metastatic urothelial carcinoma presented with generalized weakness, difficulty holding his head up and swallowing three days after receiving the second cycle of immunotherapy treatment with nivolumab (480 mg every 4 weeks). He had proximal muscle weakness but normal sensation, fatigability tests and reflexes, very abnormally high creatine kinase (CK) greater than 4,000 ng/L, EMG results of myopathy and muscle biopsy showing focal perimysial chronic inflammatory cell infiltrates. Patient 1 ultimately died due to acute hemorrhage while patient 2 had a prolonged hospitalization and rehabilitation and ultimately discharged home with hospice. Prompt symptom recognition and treatment can potentially prevent prolonged impairment and mortality associated with cancer immunotherapy.

[Therapeutic efficacy analysis of immunotherapy in small cell lung cancer].

Objective: Recently, increasing number of lung cancer patients benefit from immune-checkpoint inhibitors (ICIs). However, the data of Chinese small cell lung cancer (SCLC) patients is limited. This study aims to analyze the response and survival data of ICIs treatment in SCLC and to explore the predictive biomarkers. Methods: Forty-seven SCLC patients who received ICIs treatment from Peking University Cancer Hospital from May 2017 to September 2019 was recruited. Clinical characteristics including sex, age, smoking status, ICIs strategy, PD-L1 expression and therapeutic efficacy were collected to explore the clinical predictive biomarkers for SCLC ICIs treatment. Results: Among the 47 patients, 18 (38.3%) cases were partial repose (PR), 11 (23.4%) were stable disease (SD), 18 (38.3%) were progressive disease (PD), and the objective response rate (ORR) was 38.3%, disease control rate (DCR) was 61.7%, the median progression-free survival (PFS) was 5.3 months. ICIs monotherapy accounts for 27.7%, the ORR was 15.4%, DCR was 53.8%, median PFS was 2.7 months. Combined therapy accounts for 72.3%, the ORR was 47.1%, DCR was 64.7%, median PFS was 5.4 months. Fourteen (29.8%) patients received ICIs as the first line treatment, their ORR was 85.7%, DCR was 100%, median PFS was 9.1 month. The ORR was not related to the age, sex, body mass index (BMI), smoking status and programmed death-ligand 1 (PD-L1) expression (P>0.05). The ORRs were higher in patients underwent PD-L1 monotherapy (P=0.001), combined therapy (P=0.002) and received ICIs as the first line treatment (P<0.001). Log-rank analysis indicated that the PFS of female patients were 12.0 months, significantly longer than 4.4 months of male patients in ICIs treatment (P=0.038). Patients who received PD-L1 monotherapy, combined treatment, or ICIs as the first line treatment had longer PFS than their counterparts, though no statistical significant was observed (P>0.05). Cox multivariate analysis showed that, the gender was not an independent predictor for PFS in ICIs treatment (HR=3.777, 95%CI=0.974~30.891, P=0.054). Conclusions: Immunotherapy is an effective treatment strategy for SCLC. Patients who receive combined ICIs treatment, first line ICIs treatment and PD-L1 treatment may get greater benefits. PD-L1 expression cannot predict the response and PFS in SCLC ICIs treatment.

[Analysis of risk factors for lymphoma patients dying of cardiovascular disease].

Objective: To understand and explore the risk factors of the death of lymphoma patients from cardiovascular disease. Methods: The medical records and death information of 1 173 patients with lymphoma were collected, cases that died from cardiovascular disease were screened. A binary logistic regression model was used to analyze the independent risk factors of patients with lymphoma died from cardiovascular disease. Results: Among 1 173 patients with lymphoma, 75 (6.4%) died of cardiovascular disease, including 27 cases of coronary heart disease, 25 cases of stroke, 7 cases of hypertension, 5 cases of sudden cardiac death, 4 cases of pulmonary embolism, 3 cases of heart failure, 4 cases of others. Among the patients who survived for more than 5 years, 16.1% (35/217) died of cardiovascular disease. Among those who survived for more than 10 years, 11.7% (7/60) died of cardiovascular disease. Multivariate Logistic regression analysis showed that the primary site of lymphoma (OR=0.521, P=0.039), stage (stage Ⅱ: OR=2.487, P=0.016; stage Ⅲ: OR=3.233, P=0.002) and cardiovascular toxicity in the course of diagnosis and treatment (OR=3.019, P=0.001) are independent influencing factors for the death of cardiovascular disease in patients with lymphoma. Patients whose primary sites of lymphoma were lymph nodes had lower risk of dying from cardiovascular disease, while the patients with stage Ⅱ to Ⅲ stage and cardiovascular toxicity during diagnosis and treatment had higher risk of dying from cardiovascular disease. Conclusions: Cardiovascular disease is an important factor affecting the survival of patients with lymphoma. With the extension of survival time, the risk of dying from cardiovascular disease increases significantly. The primary site, tumor stage, and cardiovascular toxicity that occur during the diagnosis and treatment may be the independent influencing factors for patients with lymphoma that die from cardiovascular disease.

Compact radio emission indicates a structured jet was produced by a binary neutron star merger.

The binary neutron star merger event GW170817 was detected through both electromagnetic radiation and gravitational waves. Its afterglow emission may have been produced by either a narrow relativistic jet or an isotropic outflow. High-spatial-resolution measurements of the source size and displacement can discriminate between these scenarios. We present very-long-baseline interferometry observations, performed 207.4 days after the merger by using a global network of 32 radio telescopes. The apparent source size is constrained to be smaller than 2.5 milli-arc seconds at the 90% confidence level. This excludes the isotropic outflow scenario, which would have produced a larger apparent size, indicating that GW170817 produced a structured relativistic jet. Our rate calculations show that at least 10% of neutron star mergers produce such a jet.

Intravenous Acetaminophen May Be Associated with Reduced Odds of 30-Day Readmission after Total Knee Arthroplasty.

The purpose of this study was (1) to evaluate 30-day readmission rates in total knee arthroplasty (TKA) patients who either received intravenous (IV) or oral (PO) acetaminophen (APAP) perioperatively and (2) to extrapolate the potential annual cost savings on the national level. This was a review of 190,691 TKA recipients between the years 2012 and 2015 who received either IV (n = 56,475) or PO APAP (n = 134,216). All-cause readmissions that occurred between patient discharge and 30 days postdischarge were recorded. Continuous and categorical variables were evaluated using t-test and chi-square test, respectively. A logistic regression analysis was conducted to assess the effect of IV APAP on 30-day readmission. We also performed a literature review on 30-day readmission rates and risk prediction tools for TKA and correlated these with our findings. In addition, we extrapolated potential cost savings on the national level. The readmission rate was 0.04% in the IV and 0.14% in the PO APAP cohort (69% decreased risk; odds ratio = 0.31; 95% confidence interval = 0.20-0.47; p < 0.001). The readmission rate in this patient population appears to be markedly lower, when compared with previous reports. This reduction in readmissions may potentially result in $160 million savings per year. The use of IV APAP in TKA patients resulted in lower readmission rates, which may be valuable in clinical decision making by surgeons and health care administrators looking to lower costs of care.

Impact of Intravenous Acetaminophen on Lengths of Stay and Discharge Status after Total Knee Arthroplasty.

Postoperative pain remains difficult to control after total knee arthroplasty (TKA). While various modalities have been used, they have been associated with several side effects. For example, opioids have many side effects including: sedation, dizziness, nausea, vomiting, constipation, respiratory depression, and can lead to dependency. Recently, intravenous (IV) acetaminophen has been introduced as a method to manage postoperative pain. Therefore, the purpose of this study was to compare the postoperative outcomes of TKA patients who received oral acetaminophen versus IV acetaminophen. Specifically, this study evaluated: (1) the hospital lengths of stay (LOS) and (2) discharge dispositions. The Premier Database was used to review patients who underwent TKA from 2012 to 2015. A total of 134,216 TKA patients received oral acetaminophen, whereas 56,475 TKA patients received IV acetaminophen postoperatively. LOS were calculated as the number of days from the date of hospital admission to the date of discharge, and the discharge disposition was categorized as to home or to a skilled nursing facility (SNF). Compared with the oral group, the IV acetaminophen group had a 0.14 days shorter LOS (95% confidence interval [CI], -0.15 to -0.13; p < 0.001) and 22% higher chance of being discharged home (odds ratio [OR] = 1.22; 95% CI, 1.19-1.25; p < 0.001). Also, compared with the oral group, the IV group had a 13% lower chance of being discharged to a SNF (OR = 0.87; 95% CI, 0.85-0.90; p < 0.001). This study demonstrated that TKA patients who received IV acetaminophen were associated with a significantly shorter hospital LOS as well as being discharged home and fewer patients had to go to SNF. This may lead to a reduction in the total cost of health care, while, at the same time, decreasing the resource use in patients who undergo TKA.