Minimally Required Personal Protective Equipment during Local Anesthesia Surgery in COVID-19: A Simulation Study.

In the era of the coronavirus disease 2019 (COVID-19) pandemic, surgeons and medical staff are often at a high risk of infection in the operating room, especially when the patient is spontaneously breathing. In this study, we examined the minimum requirements for personal protective equipment with double surgical masks to potentially reduce unnecessary waste of supplies. Methods: Two mannequins were each connected to a test lung machine simulating a surgeon and patient with spontaneous breathing. An aerosol generator containing severe acute respiratory syndrome coronavirus 2 virion particle substitutes was connected to the patient mannequin. The sampling points for the target molecules were set at different distances from the patient mannequin and sent for multiplex quantitative polymerase chain reaction analysis. Three clinical scenarios were designed, which differed in terms of the operating room pressure and whether a fabric curtain barrier was installed between the mannequins. Results: Analysis of the multiplex quantitative polymerase chain reaction results showed that the cycle threshold (Ct) value of the target molecule increased as the distance from the aerosol source increased. In the negative-pressure operating room, the Ct values were significantly increased at all sample points compared with the normal pressure room setting. The Ct value sampled at the surgeon mannequin wearing double face masks was significantly increased when a cloth curtain barrier was set up between the two mannequins. Conclusion: Double surgical masks provide elementary surgeon protection against COVID-19 in a negative pressure operating room, with a physical barrier in place between the surgeon and patient who is spontaneously breathing during local anesthesia or sedated surgery.

The epidemiology and etiologies of respiratory tract infection in Northern Taiwan during the early phase of coronavirus disease 2019 (COVID-19) outbreak.

BACKGROUND: Coronavirus disease 2019 (COVID-19) manifests symptoms as common etiologies of respiratory tract infections (RTIs). During the pandemic of COVID-19, identifying the etiologies correctly from patients with RTI symptoms was crucial in not only disease control but preventing healthcare system from collapsing. By applying sensitive PCR-based molecular assays, we detected the etiologic agents and delineated the epidemiologic picture of RTIs in the early phase of COVID-19 pandemic. METHODS: From December 2019 to February 2020, we screened patients presented with RTIs using multiplex PCR-based diagnostic assays. Data from pediatric and adult patients were compared with different months and units in the hospital. RESULTS: Of all 1631 patients including 1445 adult and 186 pediatric patients screened, 8 viruses and 4 bacteria were identified. Positive rates were 25% in December, 37% in January, and 20% in February, with pediatric patients having higher positive rates than adults (Ps < 0.001). In pediatric patients, RhV/EnV was the most commonly detected, followed by parainfluenza viruses. Most Mycoplasma pneumoniae infection occurred in pediatric patients. RhV/EnV was the most commonly detected agent in pediatric patients admitted to intensive care units (ICUs), while influenza accounted for the majority of adult cases with critical illness. Noticeably, seasonal coronavirus ranked second in both adult and pediatric patients with ICU admission. CONCLUSION: While we focused on the pandemic of COVID-19, common etiologies still accounted for the majority of RTIs and lead to severe diseases, including other seasonal coronaviruses.

Endotoxemia-enhanced renal vascular reactivity to endothelin-1 in cirrhotic rats.

Hepatorenal syndrome (HRS), a severe complication of advanced cirrhosis, is defined as hypoperfusion of kidneys resulting from intense renal vasoconstriction in response to generalized systemic arterial vasodilatation. Nevertheless, the mechanisms have been barely investigated. Cumulative studies demonstrated renal vasodilatation in portal hypertensive and compensated cirrhotic rats. Previously, we identified that blunted renal vascular reactivity of portal hypertensive rats was reversed after lipopolysaccharide (LPS). This study was therefore conducted to delineate the sequence of renal vascular alternation and underlying mechanisms in LPS-treated cirrhotic rats. Sprague-Dawley rats were randomly allocated to receive sham surgery (Sham) or common bile duct ligation (CBDL). LPS was induced on the 28th day after surgery. Kidney perfusion was performed at 0.5 or 3 h after LPS to evaluate renal vascular response to endothelin-1 (ET-1). Endotoxemia increased serum ET-1 levels ( P < 0.0001) and renal arterial blood flow ( P < 0.05) in both Sham and CBDL rats. CBDL rats showed enhanced renal vascular reactivity to ET-1 at 3 h after LPS ( P = 0.026). Pretreatment with endothelin receptor type A (ETA) antagonist abrogated the LPS-enhanced renal vascular response in CBDL rats ( P < 0.001). There were significantly lower inducible nitric oxide synthase (iNOS) expression but higher ETA and phosphorylated extracellular signal-regulated kinase (p-ERK) expressions in renal medulla of endotoxemic CBDL rats ( P < 0.05). We concluded that LPS-induced renal iNOS inhibition, ETA upregulation, and subsequent ERK signaling activation may participate in renal vascular hyperreactivity in cirrhosis. ET-1-targeted therapy may be feasible in the control of HRS. NEW & NOTEWORTHY Hepatorenal syndrome (HRS) occurred in advanced cirrhosis after large-volume paracentesis or bacterial peritonitis. We demonstrated that intraperitoneal lipopolysaccharide (LPS) enhanced renal vascular reactivity to endothelin-1 (ET-1) in cirrhotic rats, accompanied by inducible nitric oxide synthase inhibition, endothelin receptor type A (ETA) upregulation, and subsequent extracellular signal-regulated kinase activation in renal medulla. Pretreatment with ETA antagonist abrogated the LPS-enhanced renal vascular response in common bile duct ligation rats. These findings suggest that further clinical investigation of ET-1-targeted therapy may be feasible in the control of HRS.

Risk factors and characteristics of blood stream infections in patients with newly diagnosed multiple myeloma.

BACKGROUND: Patients with multiple myeloma are generally immune-compromised either due to pronounced depression in primary antibody responses or because of anti-myeloma therapy. Infection is a major risk factor for early deaths among these patients. The impact of blood stream infections (BSI) on newly diagnosed myeloma patients has been less studied. We aimed to study the incidence and risk factors of BSI within 3 months after diagnosis of multiple myeloma in a tertiary referral center. METHODS: Between November 2002 and December 2008, consecutive patients with multiple myeloma in Taipei Veterans General Hospital were retrospectively enrolled. Characteristics of patients with or without BSI were collected. Possible factors associated with development of BSI were analyzed by Cox regression. RESULTS: There were a total of 222 patients. The incidence of BSI within 3 months after diagnosis is 11.7%. The patients with BSI had poorer survival outcomes than those without (mortality rate: 50% vs. 20.9%, p < 0.001). Moreover, advanced International Staging System stage (stage III vs. I/II: odds ratio [OR] 2.69, p = 0.049) and poor Eastern Cooperative Oncology Group (ECOG) performance status (ECOG > 2 vs. ≤ 2: OR 3.58, p = 0.005) were the independent risk factors of BSI, whereas immunoglobulin deficiency and low absolute lymphocyte count were not associated with risk of BSI development. CONCLUSIONS: Our study highlights the characteristic of myeloma patients with BSI and the importance of disease and host factors on risk of BSI. Myeloma patients with risks of BSI should be properly managed to reduce early mortality.

Atypical mycobacterial spondylitis as a challenging differential diagnosis to metastatic disease of the spine: a case report.

Disseminated Mycobacterium avium complex (MAC) infection is rarely seen in patients without acquired immune deficiency syndrome. A disseminated MAC infection presenting with symptoms that mimic tumor metastasis had not previously been reported. Few disseminated MAC infections have been reported, and all image patterns in these cases indicated destructive lesions. We present a case involving a tumor-like disseminated MAC infection with spondylitis in a 68-year-old man whose symptoms started with severe lower back pain and fever. Treatment for malignancy was performed initially but soon stopped after tissue proving MAC infection. Symptoms then improved dramatically after a four-drug combined anti-nontuberculous mycobacteria treatment.

Severe extensive bone marrow necrosis from miliary tuberculosis without granulomas and pulmonary presentations.

Bone marrow necrosis (BMN) is a rare clinicopathologic entity caused by hypoxemia after failure of the microcirculation, which frequently manifests with bone pain, fever, and peripheral cytopenia. In most reported cases of BMN resulting from miliary tuberculosis (TB), the presence of marrow granulomas, pulmonary infiltrates and/or extrapulmonary involvement is common. We report a female patient with extensive BMN from miliary TB, whose initial presentation was only severe peripheral cytopenia with extensive marrow necrosis, with neither evident pulmonary manifestations nor granulomas in the marrow biopsy. Serial Ziehl-Neelsen stains and Mycobacterium tuberculosis cultures were negative. The diagnosis of suspected miliary TB was made by consecutive positive results from polymerase chain reaction analysis for TB of marrow samples at 2 separate examination time points and a good treatment response to anti-TB therapy. Magnetic resonance imaging showed a geographic pattern of multiple signal abnormalities, indicating bone infarcts over the bilateral iliac bones and T-L-spine vertebral bodies, compatible with extensive BMN. The unusual presentation of extensive BMN with severe peripheral cytopenia in the absence of granulomas or pulmonary presentations should alert clinical physicians in epidemic areas. We discuss the use of polymerase chain reaction analysis for TB and magnetic resonance imaging for diagnosis of these patients.

Clinical characteristics of patients with Acinetobacter junii infection.

BACKGROUND AND PURPOSE: Acinetobacter junii is a human pathogen but A. junii infection is rarely reported. This study aimed to delineate the characteristics of A. junii infection. METHODS: The medical records of 34 patients who were treated at Taipei Veterans General Hospital, Taipei, Taiwan, from May 1999 to May 2007 and had A. junii isolated from sterile sites were reviewed. Isolates of A. junii were identified by using API ID 32 GN and were confirmed by analysis of the 16S-23S rRNA intergenic spacer region. RESULTS: Thirty five infections with A. junii were identified. The most common underlying conditions included prior antibiotic use (56%), central venous catheterization (50%), and malignancy (38%). Systemic inflammatory response syndrome and shock developing within 1 week were observed in 27 (77%) and 8 (23%) episodes, respectively. Eighty percent of the infectious episodes were hospital acquired. The infections were primary bacteremia (n = 32), empyema (n = 1), peritonitis (n = 1), and keratitis (n = 1). Polymicrobial infection was present in 9 episodes (26%). A. junii isolates remained susceptible to most of the tested antimicrobial agents, but the hospital-acquired isolates had higher resistance rates than the community-acquired isolates. Four patients (11.4%) died of A. junii infection despite appropriate antimicrobial therapy for 3 patients. Shock that developed within 1 week of bacteremia was associated with a poor outcome (p = 0.01). CONCLUSIONS: A. junii is an opportunistic pathogen that mainly affects patients who have had prior antimicrobial therapy, invasive procedures, or malignancy. Newly emerging infections caused by A. junii and the increasing antimicrobial resistance among hospital-acquired A. junii isolates should be monitored.

Clinical and bacteriological characteristics of pyogenic liver abscess in non-diabetic patients.

BACKGROUND AND PURPOSE: Diabetes mellitus is an important risk factor for Klebsiella pneumoniae liver abscess, but many patients with pyogenic liver abscess (PLA) do not have diabetes. This study was conducted to compare the clinical characteristics and prognostic factors of K. pneumoniae PLA with that caused by other organisms in non-diabetic patients. METHODS: The medical charts of patients with a diagnosis of PLA were retrospectively reviewed from January 2005 to December 2007. The clinical symptoms and signs, laboratory data, and risk factors were analyzed. RESULTS: There were 50 patients in the K. pneumoniae group and 34 patients in the non-K. pneumoniae group. The clinical presentations did not differ between the 2 groups. The patients in the non-K. pneumoniae group had a higher prevalence of malignant disease than those in the K. pneumoniae group (58.8% vs 6.0%; p < 0.001). Non-K. pneumoniae PLA was strongly associated with hepatobiliary tumor (p = 0.015). Among the non-K. pneumoniae isolates, Escherichia coli was the most common pathogen (n = 20; 58.8%). Forty seven K. pneumoniae isolates (94%) were susceptible to all tested antimicrobial agents except ampicillin, while the non-K. pneumoniae Gram-negative pathogens had greater resistance to first-generation cephalosporins. Poor prognostic factors included chronic renal failure (p = 0.005), abscess rupture (p = 0.036), and right lower lung infiltration (p = 0.049). CONCLUSIONS: Hepatobiliary malignancy and newly diagnosed malignancy were risk factors for non-K. pneumoniae liver abscess in non-diabetic patients. Physicians should ascertain the presence of underlying malignancy in patients with non-K. pneumoniae PLA.

Predictive value of two commercial human immunodeficiency virus serological tests in cases with indeterminate Western blot results.

BACKGROUND AND PURPOSE: Serodiagnosis of human immunodeficiency virus (HIV) infection typically requires repeatedly reactive positive screening test followed by Western blot (WB) assay. When WB assay result is indeterminate, the results of follow-up WB assay may remain inconclusive. This study evaluated use of enzyme-linked immunosorbent assay (ELISA) and particle agglutination test (PAT) as sequential screening tests with WB assay for the diagnosis of HIV infection. METHODS: From January 1, 2000 to December 31, 2003, a total of 565 serum samples collected from individuals with a previous positive or borderline positive ELISA test for HIV at regular check-up (281 samples) and a second group of individuals with known risk of HIV exposure or suspected infection based on clinical presentation (284 samples) were tested for HIV infection by ELISA, PAT and WB assay. RESULTS: The result was positive for HIV infection and confirmed by WB assay in 197 samples (22.5%), indeterminate in 127 samples (22.5%) and negative in 241 samples (42.6%). The sensitivity and specificity of ELISA were 100% and 21.6% and of PAT were 99.5% and 95%, respectively. Among the 197 HIV-infected cases, all ELISA and PAT results were concordant with WB assay except 1 (1/197) with negative PAT. Positive ELISA, positive PAT and indeterminate WB assay results were found in 9 of the 284 samples (7 individuals) from at-risk patients. Among these 7 individuals, 5 were later proved to have HIV infection. WB assay in 1 of the 7 individuals remained indeterminate 1 year later, and the remaining case was lost to follow-up. CONCLUSION: We suggest initial ELISA followed by PAT as sequential screening for HIV infection. When both screening tests are concordant but subsequent WB assay is indeterminate, further evaluation (such as nucleic acid amplification test) should be arranged as soon as possible.

Risk factors for central venous catheter-related infections in general surgery.

BACKGROUND AND PURPOSE: Central venous catheter (CVC) infection is a common problem during hospitalization and nosocomial bloodstream infection in these patients is associated with increased morbidity, mortality, and health care cost. This prospective study examined the risk factors of CVC-related infections. METHODS: During a 6-month period, a total of 281 patients who underwent central venous catheterization after general surgery were enrolled. RESULTS: The mean duration from CVC insertion to the development of infection was 7.12 days. The rate of bloodstream infection without isolation of the same organism from the catheter was 1.4% (4/281). The rate of catheter-related bloodstream infection was 6.0% (17/281). The rate of catheter bacteremia, defined as positive culture from a catheter blood sample in a patient without signs of infection, was 8.5% (24/281). The incidence of catheter-related bloodstream infection was 7.5/1000 catheter-days. Risk factors for catheter-related infection on univariate analysis included place of insertion (operating room or surgical ward), total parenteral nutrition (TPN), more than 3 tubings, and duration of catheterization. TPN was a significant risk factor in the logistic regression analysis. CONCLUSIONS: Established infection control guidelines should be rigorously observed with regard to catheter use and various risk factors controlled to prevent the occurrence of CVC-related infection, especially in patients receiving TPN.