Assessment of a PK/PD Target of Continuous Infusion Beta-Lactams Useful for Preventing Microbiological Failure and/or Resistance Development in Critically Ill Patients Affected by Documented Gram-Negative Infections.

BACKGROUND: Emerging data suggest that more aggressive beta-lactam PK/PD targets could minimize the occurrence of microbiological failure and/or resistance development. This study aims to assess whether a PK/PD target threshold of continuous infusion (CI) beta-lactams may be useful in preventing microbiological failure and/or resistance development in critically ill patients affected by documented Gram-negative infections. METHODS: Patients admitted to intensive care units from December 2020 to July 2021 receiving continuous infusion beta-lactams for documented Gram-negative infections and having at least one therapeutic drug monitoring in the first 72 h of treatment were included. A receiver operating characteristic (ROC) curve analysis was performed using the ratio between steady-state concentration and minimum inhibitory concentration (Css/MIC) ratio as the test variable and occurrence of microbiological failure as the state variable. Area under the curve (AUC) and 95% confidence interval (CI) were calculated. Independent risk factors for the occurrence of microbiological failure were investigated using logistic regression. RESULTS: Overall, 116 patients were included. Microbiological failure occurred in 26 cases (22.4%). A Css/MIC ratio ≤ 5 was identified as PK/PD target cut-off with sensitivity of 80.8% (CI 60.6-93.4%) and specificity of 90.5% (CI 74.2-94.4%), and with an AUC of 0.868 (95%CI 0.793-0.924; p < 0.001). At multivariate regression, independent predictors of microbiological failure were Css/MIC ratio ≤ 5 (odds ratio [OR] 34.54; 95%CI 7.45-160.11; p < 0.001) and Pseudomonas aeruginosa infection (OR 4.79; 95%CI 1.11-20.79; p = 0.036). CONCLUSIONS: Early targeting of CI beta-lactams at Css/MIC ratio > 5 during the treatment of documented Gram-negative infections may be helpful in preventing microbiological failure and/or resistance development in critically ill patients.

Simulation and Experimental Characterization of Lateral Imaging Resolution of Ultrasound Systems and Assessment of System Suitability for Acoustic Optic Nerve Sheath Diameter Measurement.

BACKGROUND AND PURPOSE: Optic nerve sheath diameter (ONSD) is used for the estimation of intracranial pressure (ICP). But there are still doubts about the quality of the images and the lateral resolution. Our aim is to investigate the system suitability and best lateral resolution of different ultrasound systems for acoustic ONSD measurement. METHODS: First, we calculated the theoretically lateral imaging resolution at increasing frequencies: 6.6, 10, and 15 MHz using two different ultrasound systems. Second, we created two phantoms consisting of copper wires or polyvinylchloride (PVC) strips and tested the best lateral resolution at different frequencies with the two ultrasound systems. Using the same ultrasound systems, we evaluated the anatomy of optic nerve at increasing transmission frequencies. Finally, the two probes were tested in two patients with different neurological conditions affected by an increase of ICP. RESULTS: Theoretical resolutions were .63, .43, and .41 mm, respectively, with a frequency of 6.6, 10, and 15 MHz. We found a similar lateral resolution in both phantoms: copper wire; .56 mm at 6.6 MHz, .46 mm at 10 MHz, and .44 mm at 15 MHz; and PVC strips .6 mm at 6.6 MHz, .47 mm at 10 MHz, and .40 mm at 15 MHz in accordance with experimental resolution. The ONSD thickening could be clearly displayed at frequencies higher than 7.5 MHz using the two linear probes and the two patients with an increase of ICP showed thickening of ONSD. CONCLUSION: According to our study, both systems are suitable for ultrasound OSND measurement.

Longitudinal Assessment of Transorbital Sonography, Visual Acuity, and Biomarkers for Inflammation and Axonal Injury in Optic Neuritis.

BACKGROUND AND OBJECTIVE: To investigate the relationship between optic nerve sheath diameter, optic nerve diameter, visual acuity and osteopontin, and neurofilament heavy chain in patients with acute optic neuritis. PATIENTS AND METHODS: Sonographic and visual acuity assessment and biomarker measurements were executed in 23 patients with unilateral optic neuritis and in 19 sex- and age-matched healthy controls. RESULTS: ONSD was thicker on the affected side at symptom onset (median 6.3 mm; interquartile range 6.0-6.5) than after 12 months (5.3 mm; 4.9-5.6; p < 0.001) or than in controls (5.2 mm; 4.8-5.5; p < 0.001). OND was significantly increased in the affected side (3.4 mm; 2.9-3.8) compared to healthy controls (2.7 mm; 2.5-2.9; p < 0.001) and was thicker at baseline than after 12 months (2.8 mm; 2.7-3.0; p < 0.01). Visual acuity improved significantly after 12 months (1.00; 0.90-1.00) compared to onset of symptoms (0.80; 0.40-1.00; p < 0.001). OPN levels were significantly higher in patients at presentation (median 6.44 ng/ml; 2.05-10.06) compared to healthy controls (3.21 ng/ml, 1.34-4.34; p < 0.03). Concentrations of NfH were significantly higher in patients than in controls. CONCLUSION: ONSD and OND are increased in the affected eye. OPN and NfH are elevated in patients, confirming the presence of any underlying inflammation and axonal injury.

The cloud stroke unit: 24-hour acute stroke expertise-on-demand.

The use of telemedicine, especially as it is relates to telestroke, has significantly expanded over the past one or two decades. The fact that stroke therapy is a time-critical disease process, coupled with the relative paucity of stroke-trained practitioners, makes telestroke an attractive technique of care. The authors' objective was to summarize the evidence that support the reliability of telemedicine for diagnosis and efficacy in acute stroke treatment in collaboration between hospitals in two different countries.