Reply to Taylor et al. Comment on "Manna et al. SARS-CoV-2 Inactivation in Aerosol by Means of Radiated Microwaves. Viruses 2023, 15, 1443".

SARS-CoV-2 is inactivated in aerosol (its primary mode of transmission) by means of radiated microwaves at frequencies that have been experimentally determined. Such frequencies are best predicted by the mathematical model suggested by Taylor, Margueritat and Saviot. The alignment between such mathematical prediction and the outcomes of our experiments serves to reinforce the efficacy of the radiated microwave technology and its promise in mitigating the transmission of SARS-CoV-2 in its naturally airborne state.

SARS-CoV-2 Inactivation in Aerosol by Means of Radiated Microwaves.

Coronaviruses are a family of viruses that cause disease in mammals and birds. In humans, coronaviruses cause infections on the respiratory tract that can be fatal. These viruses can cause both mild illnesses such as the common cold and lethal illnesses such as SARS, MERS, and COVID-19. Air transmission represents the principal mode by which people become infected by SARS-CoV-2. To reduce the risks of air transmission of this powerful pathogen, we devised a method of inactivation based on the propagation of electromagnetic waves in the area to be sanitized. We optimized the conditions in a controlled laboratory environment mimicking a natural airborne virus transmission and consistently achieved a 90% (tenfold) reduction of infectivity after a short treatment using a Radio Frequency (RF) wave emission with a power level that is safe for people according to most regulatory agencies, including those in Europe, USA, and Japan. To the best of our knowledge, this is the first time that SARS-CoV-2 has been shown to be inactivated through RF wave emission under conditions compatible with the presence of human beings and animals. Additional in-depth studies are warranted to extend the results to other viruses and to explore the potential implementation of this technology in different environmental conditions.

Percutaneous tracheostomy in COVID-19 patients: a new apneic approach.

BACKGROUND: Percutaneous dilation tracheostomy is an aerosol-generating procedure carrying a documented infectious risk during respiratory virus pandemics. For this reason, during the COVID-19 outbreak, surgical tracheostomy was preferred to the percutaneous one, despite the technique related complications increased risk. METHODS: We describe a new sequence for percutaneous dilation tracheostomy procedure that could be considered safe both for patients and healthcare personnel. A fiberscope was connected to a video unit to allow bronchoscopy. Guidewire positioning was performed as usual. While the established standard procedure continues with the creation of the stoma without any change in mechanical ventilation, we retracted the bronchoscope until immediately after the access valve in the mount tube, allowing normal ventilation. After 3 minutes of ventilation with 100% oxygen, mechanical ventilation was stopped without disconnecting the circuit. During apnea, the stoma was created by dilating the trachea and the tracheostomy cannula was inserted. Ventilation was then resumed. We evaluated the safeness of the procedure by recording any severe desaturation and by performing serological tests to all personnel. RESULTS: Thirty-six patients (38%) of 96 underwent tracheostomy; 22 (23%) percutaneous dilation tracheostomies with the new approach were performed without any desaturation. All personnel (150 operators) were evaluated for serological testing: 9 (6%) had positive serology but none of them had participated in tracheostomy procedures. CONCLUSION: This newly described percutaneous dilation tracheostomy technique was not related to severe desaturation events and we did not observe any positive serological test in health workers who performed the tracheostomies.

COVID-19 second wave: appropriateness of admissions to the Emergency Department of a main metropolitan hospital in Milan.

BACKGROUND: In Europe, Italy and Lombardy, in autumn 2020, there was a steep increase in reported cases due to the second epidemic wave of SARS-Cov-2 infection. We aimed to evaluate the appropriateness of COVID-19 patients' admissions to the ED of the San Raffaele Hospital. METHODS: We compared data between the inter-wave period (IWP, from 1st to 30th September) and the second wave period (WP, 1st October to 15th November) focusing on the ED presentation, discharge priority colour code and outcomes. RESULTS: Out of 977 admissions with a SARS-Cov-2 positive swab, 6% were in the IWP and 94% in the WP. Red, yellow and white code increased (these latter from 1.8% to 5.4%) as well as self-presented in yellow and white code. Discharges home increased from 1.8% to 5.4%, while hospitalizations decreased from 63% to 51%. DISCUSSION: We found a rise in white codes (among self-presented patients), indicating inappropriateness of admissions. The increase in discharges suggests that several patients did not require hospitalization. CONCLUSIONS: The pandemic brought out the fundamental role of primary care to manage patients with low-intensity needs. The important increase in ED admissions of COVID-19 patients caused a reduction of NO-COVID-19 patients, with possible inadequate treatment.

Continuous infusion versus intermittent administration of meropenem in critically ill patients (MERCY): A multicenter randomized double-blind trial. Rationale and design.

OBJECTIVE: Meropenem is a ß-lactam, carbapenem antibacterial agent with antimicrobial activity against gram-negative, gram-positive and anaerobic micro-organisms and is important in the empirical treatment of serious infections in Intensive Care Unit (ICU) patients. Multi-drug resistant gram-negative organisms, coupled with scarcity of new antibiotic classes, forced healthcare community to optimize the therapeutic potential of available antibiotics. Our aim is to investigate the effect of continuous infusion of meropenem against bolus administration, as indicated by a composite outcome of reducing death and emergence of extensive or pan drug-resistant pathogens in a population of ICU patients. DESIGN: Double blind, double dummy, multicenter randomized controlled trial (1:1 allocation ratio). SETTING: Tertiary and University hospitals. INTERVENTIONS: 600 ICU patients with sepsis or septic shock, needing by clinical judgment antibiotic therapy with meropenem, will be randomized to receive a continuous infusion of meropenem 3 g/24 h or an equal dose divided into three daily boluses (i.e. 1g q8h). MEASUREMENTS: The primary endpoint will be a composite outcome of reducing death and emergence of extensive or pan drug-resistant pathogens. Secondary endpoints will be death from any cause at day 90, antibiotic-free days at day 28, ICU-free days at day 28, cumulative SOFA-free (Sequential Organ Failure Assessment) score from randomization to day 28 and the two, separate, components of the primary endpoint. We expect a primary outcome reduction from 52 to 40% in the continuous infusion group. CONCLUSIONS: The trial will provide evidence for choosing intermittent or continuous infusion of meropenem for critically ill patients with multi-drug resistant gram-negative infections.

Angiotensin II infusion and markers of organ function in invasively ventilated COVID-19 patients.

Objective: The use of angiotensin II in invasively ventilated patients with coronavirus disease 2019 (COVID-19) is controversial. Its effect on organ function is unknown. Design: Prospective observational study. Setting: Intensive care unit (ICU) of a tertiary academic hospital in Milan, Italy. Participants: Adult patients receiving mechanical ventilation due to COVID-19. Interventions: Use angiotensin II either as rescue vasopressor agent or as low dose vasopressor support. Main outcome measures: Patients treated before angiotensin II was available or treated in an adjacent COVID-19 ICU served as controls. For data analysis, we applied Bayesian modelling as appropriate. We assessed the effects of angiotensin II on organ function. Results: We compared 46 patients receiving angiotensin II therapy with 53 controls. Compared with controls, angiotensin II increased the mean arterial pressure (median difference, 9.05 mmHg; 95% CI, 1.87-16.22; P = 0.013) and the PaO2/FiO2 ratio (median difference, 23.17; 95% CI, 3.46-42.88; P = 0.021), and decreased the odds ratio (OR) of liver dysfunction (OR, 0.32; 95% CI, 0.09-0.94). However, angiotensin II had no effect on lactate, urinary output, serum creatinine, C-reactive protein, platelet count, or thromboembolic complications. In patients with abnormal baseline serum creatinine, Bayesian modelling showed that angiotensin II carried a 95.7% probability of reducing the use of renal replacement therapy (RRT). Conclusions: In ventilated patients with COVID-19, angiotensin II therapy increased blood pressure and PaO2/FiO2 ratios, decreased the OR of liver dysfunction, and appeared to decrease the risk of RRT use in patients with abnormal baseline serum creatinine. However, all of these findings are hypothesis-generating only. Trial registration:ClinicalTrials.gov NCT04318366.

Acute Pain Service: A 10-Year Experience.

BACKGROUND: Pain management after surgery is crucial to decrease perioperative morbidity and mortality. Acute pain services (APS) are multidisciplinary teams that represent a modern strategy to address pain inside hospitals. The APS defines and applies pain treatment protocols specific for each surgery. To evaluate the performance of the APS at our institute, we performed a large retrospective cohort study focusing on complications of epidural analgesia and IV opiates. METHODS: Data from the 10 years of activity of the APS were collected. Pain was assessed using the VAS at rest (VASr) and during movement (VASm) at each daily visit; the presence of side effects and complications was also assessed. RESULTS: A total of 17,913 adult patients were followed by APS during the study period. Epidural analgesia was used in 7,776 cases (43%), while 9,239 (52%) patients used IV patient-controlled analgesia (PCA). A combination of the 2 was used in 87 patients (0.5%). A total of 456 perineural catheters (2.6%) were placed, while 442 patients(2.5%) used other analgesic techniques. We recorded 163 dural punctures during catheter placement, with no epidural hematoma, epidural abscess, or meningitis, and no permanent modification in sensitive or motor functions. CONCLUSIONS: In our large case series, APS was confirmed safe and effective in treating postoperative pain, using both epidural analgesia and IV PCA with morphine.

Remifentanil in cardiac surgery: a meta-analysis of randomized controlled trials.

OBJECTIVE: The authors conducted a review of randomized controlled trials to identify advantages in clinically relevant outcomes in patients undergoing cardiac surgery with remifentanil. DESIGN: Meta-analysis. SETTING: Hospitals. PARTICIPANTS: A total of 1,473 patients from 16 randomized trials. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULT: PubMed, BioMedCentral, and conference proceedings were searched (updated May 2010) for randomized trials that compared remifentanil with fentanyl or sufentanil in cardiac anesthesia. Four independent reviewers performed data extraction, with divergences resolved by consensus. Overall analysis showed that the use of remifentanil was associated with a significant reduction in postoperative mechanical ventilation (WMD = -139 min [-244, -32], p for effect = 0.01, p for heterogeneity < 0.001, I(2) = 89%); length of hospital stay (WMD = -1.08 days [-1.60, -0.57], p for effect < 0.0001, p for heterogeneity = 0.004, I(2) = 71%); and cardiac troponin-I release (WMD = -2.08 ng/mL [-3.93, -0.24], p for effect = 0.03, p for heterogeneity < 0.02, I(2) = 74%). No difference was noted in mortality (3/344 [0.87%] in the remifentanil group vs [1.06%] the control group, OR 0.76 [0.17-3.38], p for effect = 0.72, p for heterogeneity = 0.35, I(2) = 5%). CONCLUSIONS: Remifentanil reduces cardiac troponin release, time of mechanical ventilation, and length of hospital stay in patients undergoing cardiac surgery.

Adverse events during monitored anesthesia care for GI endoscopy: an 8-year experience.

BACKGROUND: The importance of sedation during endoscopy is well established. There is no consensus about the best techniques for sedation, which specialist should perform it, and in which location. OBJECTIVE: To provide data on the epidemiology of adverse events during sedation for endoscopy. DESIGN: Retrospective analysis of a prospective database. SETTING: Endoscopy unit of a university hospital. PROCEDURES: A total of 17,999 procedures performed over 8 years. INTERVENTIONS: Sedation for GI endoscopy. MAIN OUTCOME MEASUREMENTS: We recorded the following information: sex, age, body mass index, smoking habits, American Society of Anesthesiologists and Mallampati scores, duration of the procedure, type of sedative drug administered, whether the procedure was performed emergently, and endoscopic interventions during the maneuver. Adverse events were defined as occurrences that warranted intervention and were classified as hypotension, desaturation, bradycardia, hypertension, arrhythmia, aspiration, respiratory depression, vomiting, cardiac arrest, respiratory arrest, angina, hypoglycemia, and/or allergic reaction. RESULTS: Deep sedation with intravenous propofol target controlled infusion pump was the most frequently used means of administering sedation. Adverse events were rare in both the adult (4.5%) and pediatric (2.6%) populations. Six complications occurred in more than 0.1% of adult cases: arterial hypotension, desaturation, bradycardia, arterial hypertension, arrhythmia, and aspiration. Only bradycardia (2.1%) and hypotension (0.44%) occurred in children. Three adult patients (0.017%) died, and no pediatric patients died. Some predictive models for the occurrence of complications are proposed. LIMITATIONS: Retrospective analysis, single-center data collection. CONCLUSIONS: Deep sedation during endoscopic procedures is safe in both adults and children. Our data may be useful for the future planning of new clinical strategies in this setting.