Tracheostomy in critically ill patients with SARS 2 COVID-19 infection: a prospective observational multi-center study of short- and long-term outcomes.

Background: We report the characteristics, timing, and factors related to the decision to perform a tracheostomy in patients with confirmed COVID-19 infection admitted to eight Italian intensive care units (ICUs). Materials and methods: Prospective observational cohort study of patients with COVID-19 disease on mechanical ventilation. Long-term functional impairment (up to 180 days' post-hospital discharge) was assessed using the Karnofsky scale. Kaplan-Meier analysis assessed differences in survival and freedom from tracheostomy in relation to ICU stay. Cox regression model was used to assess which variables impacted on tracheostomy as a categorical outcome. Results: A total of 248 patients were recruited in the eight participating ICUs. Patients undergoing tracheostomy (n = 128) had longer ICU (25 (18-36) vs. 10 (7-16), P = 0.001) and hospital (37 (26.5-50) vs. 19 (8.5-34.5) P = 0.02) stays. ICU and hospital mortality of patients tracheostomized was 34% and 37%, respectively. Cumulative survival Kaplan-Meier analysis documented improved survival rates in patients undergoing tracheostomy (Log-Rank, Mantel-Cox = 4.8, P = 0.028). Median Karnofsky scale values improved over time but were similar between survivors receiving or not receiving tracheostomy. No healthcare worker involved in the tracheostomy procedure developed COVID-19 infection during the study period. Conclusions: Patients with COVID-19 infection who underwent tracheostomy had a better cumulative survival but similar long-term functional outcomes at 30, 60, and 180 days after hospital discharge.

Association between implantable defibrillator-detected sleep apnea and atrial fibrillation: The DASAP-HF study.

INTRODUCTION: The Respiratory Disturbance Index (RDI) computed by an implantable cardioverter defibrillator (ICD) algorithm accurately identifies severe sleep apnea (SA). In the present analysis, we tested the hypothesis that RDI could also predict atrial fibrillation (AF) burden. METHODS: Patients with ejection fraction ≤35% implanted with an ICD were enrolled and followed up for 24 months. One month after implantation, patients underwent a polysomnographic study. The weekly mean RDI value was considered, as calculated during the entire follow-up period and over a 1-week period preceding the sleep study. The endpoints were as follows: daily AF burden of ≥5 min, ≥6 h, ≥23 h. RESULTS: Here, 164 patients had usable RDI values during the entire follow-up period. Severe SA (RDI ≥ 30 episodes/h) was diagnosed in 92 (56%) patients at the time of the sleep study. During follow-up, AF burden ≥ 5 min/day was documented in 70 (43%), ≥6 h/day in 48 (29%), and ≥23 h/day in 33 (20%) patients. Device-detected RDI ≥ 30 episodes/h at the time of the polygraphy, as well as the polygraphy-measured apnea hypopnea index ≥ 30 episodes/h, were not associated with the occurrence of the endpoints, using a Cox regression model. However, using a time-dependent model, continuously measured weekly mean RDI ≥ 30 episodes/h was independently associated with AF burden ≥ 5 min/day (hazard ratio [HR]: 2.13, 95% confidence interval [CI]: 1.24-3.65, p = .006), ≥6 h/day (HR: 2.75, 95% CI: 1.37-5.49, p = .004), and ≥23 h/day (HR: 2.26, 95% CI: 1.05-4.86, p = .037). CONCLUSIONS: In heart failure patients, ICD-diagnosed severe SA on follow-up data review identifies patients who are from two- to three-fold more likely to experience an AF episode, according to various thresholds of daily AF burden.

A Tele-Rehabilitation Platform for Shoulder Motor Function Recovery Using Serious Games and an Azure Kinect Device.

BACKGROUND: Tele-rehabilitation is gaining importance due to the increasing need for objectiveness in the evaluation of patients with impaired motor functions. Low-cost marker-less motion capture systems are becoming key enabling technologies as support in the treatment of musculoskeletal diseases. OBJECTIVES: The goal of this work is to investigate the use of the Microsoft Azure Kinect device to develop a tele-rehabilitation platform for shoulder motor function recovery. The platform comprehends a set of serious games, which are fundamental to increase the patients' engagement in shoulder rehabilitation. METHODS: Starting from a set of functionalities identified together with the medical personnel of an Italian hospital, the Azure Kinect device has been used as motion capture system to interact with the serious games. Mobile applications for patients and physicians have been developed to manage the rehabilitation process. RESULTS: The solution has been tested by the involved medical personnel. It has been considered interesting and promising. Further improvements in the design of the virtual environment of the serious games are required. CONCLUSION: The presented platform is a starting point to develop a complete IT solution for the daily shoulder rehabilitation.

Bacterial infections in critically ill patients with SARS-2-COVID-19 infection: results of a prospective observational multicenter study.

PURPOSE: To investigate the prevalence, incidence and characteristics of bacterial infections and their impact on outcome in critically ill patients infected with COVID-19. METHODS: We conducted a prospective observational study in eight Italian ICUs from February to May 2020; data were collected through an interactive electronic database. Kaplan-Meier analysis (limit product method) was used to identify the occurrence of infections and risk of acquisition. RESULTS: During the study period 248 patients were recruited in the eight participating ICUs. Ninety (36.3%) patients developed at least one episode of secondary infection. An ICU length of stay between 7 and 14 days was characterized by a higher occurrence of infectious complications, with ventilator-associated pneumonia being the most frequent. At least one course of antibiotic therapy was given to 161 (64.9%) patients. Overall ICU and hospital mortality were 33.9% and 42.9%, respectively. Patients developing bacteremia had a higher risk of ICU mortality [45.9% vs. 31.6%, odds ratio 1.8 (95% CI 0.9-3.7), p = 0.069] and hospital mortality [56.8% vs. 40.3%, odds ratio 1.9 (95% CI 1.1-3.9), p = 0.04]. CONCLUSION: In critically ill patients infected with COVID-19 the incidence of bacterial infections is high and associated with worse outcomes. Regular microbiological surveillance and strict infection control measures are mandated.

Early extubation with immediate non-invasive ventilation versus standard weaning in intubated patients for coronavirus disease 2019: a retrospective multicenter study.

In patients intubated for hypoxemic acute respiratory failure (ARF) related to novel coronavirus disease (COVID-19), we retrospectively compared two weaning strategies, early extubation with immediate non-invasive ventilation (NIV) versus standard weaning encompassing spontaneous breathing trial (SBT), with respect to IMV duration (primary endpoint), extubation failures and reintubations, rate of tracheostomy, intensive care unit (ICU) length of stay and mortality (additional endpoints). All COVID-19 adult patients, intubated for hypoxemic ARF and subsequently extubated, were enrolled. Patients were included in two groups, early extubation followed by immediate NIV application, and conventionally weaning after passing SBT. 121 patients were enrolled and analyzed, 66 early extubated and 55 conventionally weaned after passing an SBT. IMV duration was 9 [6-11] days in early extubated patients versus 11 [6-15] days in standard weaning group (p = 0.034). Extubation failures [12 (18.2%) vs. 25 (45.5%), p = 0.002] and reintubations [12 (18.2%) vs. 22 (40.0%) p = 0.009] were fewer in early extubation compared to the standard weaning groups, respectively. Rate of tracheostomy, ICU mortality, and ICU length of stay were no different between groups. Compared to standard weaning, early extubation followed by immediate NIV shortened IMV duration and reduced the rate of extubation failure and reintubation.

Prognostic value of implantable defibrillator-computed respiratory disturbance index: The DASAP-HF study.

BACKGROUND: Sleep apnea, as measured by polysomnography, is associated with adverse outcomes in heart failure. The DASAP-HF (Diagnosis and Treatment of Sleep Apnea in Patient With Heart Failure) study previously demonstrated that the respiratory disturbance index (RDI) computed by the ApneaScan algorithm (Boston Scientific) accurately identifies severe sleep apnea in implantable cardioverter-defibrillator (ICD) patients. OBJECTIVE: The purpose of the long-term study phase was to assess the incidence of clinical events after 24 months and investigate the association with RDI values. METHODS: Patients with left ventricular ejection fraction ≤35% implanted with an ICD were enrolled and followed-up for 24 months. The RDI calculated at 1 month after implantation was used to stratify patients (below or above 30 episodes/h). The endpoints were all-cause death and a combination of all-cause death or cardiovascular hospitalization. RESULTS: Of the 265 enrolled patients, 224 had usable RDI values. Severe sleep apnea (RDI ≥30 episodes/h) was diagnosed in 115 patients (51%). These patients were more frequently male (84% vs 72%; P = .030) and had higher creatinine levels. During median follow-up of 25 months, 19 patients (8%) died. Cardiovascular hospitalizations were reported in 19 patients (8%). The risk of all-cause death was higher in patients with RDI ≥30 episodes/h (hazard ratio [HR] 3.33; 95% confidence interval [CI] 1.35-8.21; P = .023), as well as the risk of all-cause death or cardiovascular hospitalization (HR 1.94; 95% CI 1.01-3.76; P = .048). At multivariate analysis, independent predictors of death were RDI ≥30 episodes/h (HR 4.02; 95% CI 1.16-13.97; P = .029) and creatinine levels (HR 2.36; 95% CI 1.26-4.42; P = .008). CONCLUSION: In heart failure patients implanted with an ICD, higher RDI values are associated with death and cardiovascular hospitalizations. Device-detected severe sleep apnea independently predicts death.

Antiplatelet Therapy with Cangrelor in Patients Undergoing Surgery after Coronary Stent Implantation: A Real-World Bridging Protocol Experience.

Objective The aim of the study is to describe the real-world use of the P2Y 12 inhibitor cangrelor as a bridging strategy in patients at high thrombotic risk after percutaneous coronary intervention (PCI) and referred to surgery requiring perioperative withdrawal of dual antiplatelet therapy (DAPT). Materials and Methods We collected data from nine Italian centers on patients with previous PCI who were still on DAPT and undergoing nondeferrable surgery requiring DAPT discontinuation. A perioperative standardized bridging protocol with cangrelor was used. Results Between December 2017 and April 2019, 24 patients (mean age 72 years; male 79%) were enrolled. All patients were at high thrombotic risk after PCI and required nondeferrable intermediate to high bleeding risk surgery requiring DAPT discontinuation (4.6 ± 1.7 days). Cangrelor infusion was started at a bridging dose (0.75 µg/kg/min) 3 days before planned surgery and was discontinued 6.6 ± 1.5 hours prior to surgical incision. In 55% of patients, cangrelor was resumed at 9 ± 6 hours following surgery for a mean of 39 ± 38 hours. One cardiac death was reported after 3 hours of cangrelor discontinuation prior to surgery. No ischemic outcomes occurred after surgery and up to 30-days follow-up. The mean hemoglobin drop was <2 g/dL; nine patients received blood transfusions consistent with the type of surgery, but no life-threatening or fatal bleeding occurred. Conclusion Perioperative bridging therapy with cangrelor is a feasible approach for stented patients at high thrombotic risk and referred to surgery requiring DAPT discontinuation. Larger studies are warranted to support the safety of this strategy.

Single-Stage Localization and Thoracoscopic Removal of Nonpalpable Pulmonary Nodules in a Hybrid Operating Room.

OBJECTIVE: We report our experience with simultaneous localization and thoracoscopic removal for nonpalpable undiagnosed pulmonary nodules. METHODS: All patients with nonpalpable lesions requiring video-assisted thoracoscopic surgery (VATS) wedge resection underwent localization of the targets and surgical removal in a hybrid operating room. Lesions were considered nonpalpable if they were small (<1 cm), deep (>1 cm from the surface), subsolid, or located within a dystrophic area. In all cases, intraoperative cone-beam computed tomography was performed for nodule localization and targeting, metal hookwires, or coils were alternatively used for intraoperative marking. RESULTS: From April 2016 to November 2019, 39 image-guided VATS (iVATS) were performed. The mean lesion size was 12 ± 6 mm. The mean distance from the deep edge of the lesion to the pleural surface was 24 ± 9 mm. The localization was performed with 20 hookwires and 19 coils. iVATS localization was successful in 36 patients (92.3%). Thirty-seven wedge resections were completed by VATS, 2 (5%) required conversion to thoracotomy. In 9 patients with intraoperative diagnosis of lung cancer, a lobectomy was performed (7 VATS and 2 thoracotomies). Mean length of iVATS localization was 30 ± 13 minutes. Median postoperative length of stay was 4 days (IQR 3 to 5). CONCLUSIONS: iVATS seems to be a helpful tool for simultaneous localization and removal of nonpalpable nodules. A versatile approach using different devices seems advisable for the removal of targets in every clinical scenario reducing VATS conversion rate. Future research is required to compare iVATS with traditional preoperative localization techniques.

Enhanced recovery after surgery: adherence and outcomes in elderly patients undergoing VATS lobectomy.

OBJECTIVES: To evaluate whether ERAS is feasible and beneficial in elderly patients undergoing VATS lobectomy for lung cancer. METHODS: From February 2016 to March 2019, 182 patients were included into a 17-items ERAS pathway. Patients were divided into two groups according to age: Group A (< 75 years) 138 patients and Group B (≥ 75 years) 44 patients. End points were: length of stay (LoS), 30-day morbidity, 90-day mortality, 30-day re-admittance rate, and ERAS-score (number of ERAS objectives achieved). RESULTS: Elderly patients had significantly more chronic renal failure (p = 0.039) and a worse pulmonary function. Mean FEV1% was 101.6% (± 21.0% SD) and 90.8% (± 19.1% SD) and mean FEV1/FVC was 0.75 (± 0.10 SD) and 0.68 (± 0.12 SD) for group A and B, respectively (p = 0.02 and p = 0.01). Median LoS was longer in Group B (6 days) than in Group A (5 days; p = 0.006). Morbidity was higher for elderly patients (A 32.6% vs B 56.8%; p = 0.007), major complication rates were similar (p = 0.782). No post-operative mortality was observed, re-admittance rates were similar (A 7.8% vs B 11.5%; p = 0.548). Mean ERAS-scores were 13.8 (± 1.83 SD) for Group A and 13.4 (± 1.98 SD) for Group B (p = 0.240). Multivariable analysis showed previous major surgery (p = 0.028), COPD (p = 0.027), history of arrhythmic disease (p = 0.015), post-operative complications (p < 0.001), and ERAS-score (p < 0.001) as independent predictive factors of LoS, age did not significantly influence LoS. CONCLUSIONS: Elderly patients adhere to an ERAS protocol similarly to younger ones. ERAS pathway in VATS lobectomy patients seems to be beneficial regardless the age.

Clinical guidelines for perioperative hemodynamic management of non cardiac surgical adult patients.

Perioperative hemodynamic management, through monitoring and intervention on physiological parameters to improve cardiac output and oxygen delivery (goal-directed therapy, GDT), may improve outcome. However, an Italian survey has revealed that hemodynamic protocols are applied by only 29.1% of anesthesiologists. Aim of this paper is to provide clinical guidelines for a rationale use of perioperative hemodynamic management in non cardiac surgical adult patients, oriented for Italy and updated with most recent studies. Guidelines were elaborated according to NICE (National Institute for Health and Care Excellence) and GRADE system (Grading of Recommendations of Assessment Development and Evaluations). Key questions were formulated according to PICO system (Population, Intervention, Comparators, Outcome). Guidelines and systematic reviews were identified on main research databases and strategy was updated to June 2018. There is not enough good quality evidence to support the adoption of a GDT protocol in order to reduce mortality, although it may be useful in high risk patients. Perioperative GDT protocol to guide fluid therapy is recommended to reduce morbidity. Continuous monitoring of arterial pressure may help to identify short periods of hemodynamic instability and hypotension. Fluid strategy should aim to a near zero balance in normovolemic patients at the beginning of surgery, and a slight positive fluid balance may be allowed to protect renal function. Drugs such as inotropes, vasocostrictors, and vasodilatator should be used only when fluids alone are not sufficient to optimize hemodynamics. Perioperative GDT protocols are associated with a reduction in costs, although no economic study has been performed in Italy.

Burnout in Cardiac Anesthesiologists: Results From a National Survey in Italy.

OBJECTIVE: There is increasing burnout incidence among medical disciplines, and physicians working in emergency settings seem at higher risk. Cardiac anesthesiology is a stressful anesthesiology subspecialty dealing with high-risk patients. The authors hypothesized a high risk of burnout in cardiac anesthesiologists. DESIGN: National survey conducted on burnout. SETTING: Italian cardiac centers. PARTICIPANTS: Cardiac anesthesiologists. INTERVENTIONS: The authors administered via email an anonymous questionnaire divided into 3 parts. The first 2 parts evaluated workload and private life. The third part consisted of the Maslach Burnout Inventory test with its 3 constituents: high emotional exhaustion, high depersonalization, and low personal accomplishment. MEASUREMENTS AND MAIN RESULTS: The authors measured the prevalence and risk of burnout through the Maslach Burnout Inventory questionnaire and analyzed factors influencing burnout. Among 670 contacts from 71 centers, 382 cardiac anesthesiologists completed the survey (57%). The authors found the following mean Maslach Burnout Inventory values: 14.5 ± 9.7 (emotional exhaustion), 9.1 ± 7.1 (depersonalization), and 33.7 ± 8.9 (personal accomplishment). A rate of 34%, 54%, and 66% of respondents scored in "high" or "moderate-high" risk of burnout (emotional exhaustion, depersonalization, and personal accomplishment, respectively). The authors found that, if offered to change subspecialty, 76% of respondents would prefer to remain in cardiac anesthesiology. This preference and parenthood were the only 2 investigated factors with a protective effect against all components of burnout. Significantly lower burnout scores were found in more experienced anesthesiologists. CONCLUSION: A relatively high incidence of burnout was found in cardiac anesthesiologists, especially regarding high depersonalization and low personal accomplishment. Nonetheless, most of the respondents would choose to remain in cardiac anesthesiology.

A Multidisciplinary Approach on the Perioperative Antithrombotic Management of Patients With Coronary Stents Undergoing Surgery: Surgery After Stenting 2.

Perioperative management of antithrombotic therapy in patients treated with coronary stents undergoing surgery remains poorly defined. Importantly, surgery represents a common reason for premature treatment discontinuation, which is associated with an increased risk in mortality and major adverse cardiac events. However, maintaining antithrombotic therapy to minimize the incidence of perioperative ischemic complications may increase the risk of bleeding complications. Although guidelines provide some recommendations with respect to the perioperative management of antithrombotic therapy, these have been largely developed according to the thrombotic risk of the patient and a definition of the hemorrhagic risk specific to each surgical procedure, key to defining the trade-off between ischemia and bleeding, is not provided. These observations underscore the need for a multidisciplinary collaboration among cardiologists, anesthesiologists, hematologists and surgeons to reach this goal. The present document is an update on practical recommendations for standardizing management of antithrombotic therapy management in patients treated with coronary stents (Surgery After Stenting 2) in various types of surgery according to the predicted individual risk of thrombotic complications against the anticipated risk of surgical bleeding complications. Cardiologists defined the thrombotic risk using a "combined ischemic risk" approach, while surgeons classified surgeries according to their inherent hemorrhagic risk. Finally, a multidisciplinary agreement on the most appropriate antithrombotic treatment regimen in the perioperative phase was reached for each surgical procedure.

Tailored intraoperative localization of non-palpable pulmonary lesions for thoracoscopic wedge resection using hybrid room technology.

INTRODUCTION: VATS wedge resection can require conversion to thoracotomy when pulmonary lesions cannot be identified. Hybrid operating rooms (HORs) provide real-time image acquisition capabilities allowing the intraoperative placement of markers to facilitate the removal of non-palpable nodules during VATS. OBJECTIVES: To present our workflow based on the alternative use of two different markers according to the location of the lung lesion and report our initial results. METHODS: All consecutive patients with non-palpable lesions requiring VATS wedge resection underwent localization of the targets in HOR. Lesions were considered non-palpable if they were small (<1 cm), deep (>1 cm from surface), subsolid, or located within a dystrophic area. Anesthetized patients were placed in lateral decubitus. Cone-beam CT (CBCT) was performed, and the needle trajectory was planned using Syngo iGuide Needle Guidance. Metal hook-wire or coil was placed, according to our workflow, close to the lesion and their position was verified by CBCT or fluoroscopy. RESULTS: Eleven VATS wedge resections were performed in 10 patients with 12 non-palpable lesions. The localization was performed with seven hook-wires and four coils in 30 minutes (range 17-56 minutes). The median estimated total effective dose was 11.6 mSv (range 1.9-24.7 mSv). Eleven lesions were removed by VATS, and one deep nodule required a thoracotomy. No complications were observed. CONCLUSIONS: Our experience confirms that HOR is suitable for simultaneous localization and VATS resection of 'difficult' pulmonary lesions. A versatile approach, using different devices, seems advisable for the removal of targets in every clinical scenario, reducing the VATS conversion rate.

Device pacing diagnostics overestimate effective cardiac resynchronization therapy pacing results of the hOLter for Efficacy analysis of CRT (OLÉ CRT) study.

BACKGROUND: A high percentage of biventricular (BiV) or left ventricular (LV) pacing in cardiac resynchronization therapy (CRT) devices has been associated with superior clinical outcomes. However, the percent ventricular (%V) pacing reported by CRT devices simply indicates the number of paces the device has delivered and not the proportion of pacing that has captured the LV effectively. OBJECTIVE: The purpose of this study was to determine whether a beat-by-beat evaluation of effective pacing would provide a more accurate evaluation of CRT delivery. METHODS: An automatic electrogram (EGM)-based algorithm that classifies each LV pace as effective or ineffective based on detection of QS/QS-r morphology on the unipolar LV EGM during pacing was developed and validated. LV EGMs that were recorded by 24-hour Holter from 57 CRT patients were postprocessed. The percent effective CRT (%e-CRT) pacing was calculated by dividing the time spent in e-CRT pacing by the total time of the recording. RESULTS: In this CRT cohort, the average %V pacing (94.8% ± 8%) significantly overestimated the %e-CRT pacing (87.5% ± 23%; P <.001). A significant minority of subjects (18%) had a discrepancy of at least 3 percentage points between %V pacing and %e-CRT pacing (mean 39% ± 41%). CONCLUSION: Current device pacing diagnostics overestimate the amount of CRT pacing actually delivered. The new algorithm quantifies ineffective CRT pacing, which enables clinicians to identify patients with this issue and to address the reasons behind suboptimal CRT delivery.

Totally submuscular implantation of subcutaneous implantable cardioverter defibrillator: a safe and effective solution for obese or oversized patients.

The subcutaneous implantable cardioverter-defibrillator (S-ICD) is a safe alternative to transvenous ICD. We describe a submuscular S-ICD placement technique in a severely obese with an oversized chest. Submuscular configuration allows optimal system positioning and impendence values warranting a safe and effective shock transmission. This technique is safe and improves patients comfort.

Vasoactive Drugs and Hemodynamic Monitoring in Pediatric Cardiac Intensive Care: An Italian Survey.

BACKGROUND: Little is known about practitioner preference, the availability of technology, and variability in practice with respect to hemodynamic monitoring and vasoactive drug use after congenital heart surgery. The aim of this study was to characterize current hospital practices related to the management of low cardiac output syndrome (LCOS) across Italy. METHODS: We issued a 22-item questionnaire to 14 Italian hospitals performing pediatric cardiac surgery. RESULTS: Electrocardiogram, invasive blood pressure, central venous pressure, pulse oximetry, diuresis, body temperature, arterial lactate, and blood gas analysis were identified as routine in hemodynamic monitoring. With regard to advanced hemodynamic monitoring, pulmonary arterial catheter and transpulmonary thermodilution were available in 43% of the centers, uncalibrated pulse contour methods in 29% of the centers, and transesophageal/transthoracic echocardiograms in all of the centers. Dopamine added to milrinone was the most frequent drug regimen for LCOS prevention after cardiopulmonary bypass. Overall, 86% of centers used milrinone alone as the initial treatment for LCOS with elevated systemic vascular resistances and levosimendan, the second preferred choice. In cases of LCOS with low vascular resistance, epinephrine was the first choice (10 centers), dopamine was the second choice (4 centers), followed by vasopressin and norepinephrine (3 centers). For treatment of LCOS with elevated pulmonary resistances, milrinone was the first choice (eight centers), followed by inhaled nitric oxide (five centers). CONCLUSIONS: The survey shows that advanced hemodynamic monitoring is rarely performed. The most commonly used vasoactive drugs are milrinone, levosimendan, dopamine, epinephrine, vasopressin, and norepinephrine. Guidelines on the topic are warranted.

Transesophageal ecocardiography: the correct intraoperative way to detect the source of peripheral embolism in an emergency.

Arterial thromboembolism in patients with an unknown source of embolization is associated with significant morbidity and mortality. Once the acute process has been treated, a search of the offending embolic source must be conducted to prevent additional episodes. The most common sources of peripheral embolism include intracardiac thrombi (>85%), thrombus within arterial aneurysm, thrombus overlying complex atherosclerotic plaques, and paradoxical embolization from deep venous thrombus. A strong association has been shown between protruding, noncalcified plaques>4 cm in the aorta detected by transesophageal echocardiography and the risk of embolism. Moreover, as many as 25-50% of protruding plaques may have superimposed mobile thrombi ranging from one to several centimeters, and this imparts a high embolic risk. The formation of thrombi in morphologically normal aorta is a rare event. We report a case of peripheral embolization in a young man caused by a thrombus in the descending aorta detected by transesophageal echocardiography.

Role of alveolar ß2-adrenergic receptors on lung fluid clearance and exercise ventilation in healthy humans.

BACKGROUND: In experimental conditions alveolar fluid clearance is controlled by alveolar ß2-adrenergic receptors. We hypothesized that if this occurs in humans, then non-selective ß-blockers should reduce the membrane diffusing capacity (DM), an index of lung interstitial fluid homeostasis. Moreover, we wondered whether this effect is potentiated by saline solution infusion, an intervention expected to cause interstitial lung edema. Since fluid retention within the lungs might trigger excessive ventilation during exercise, we also hypothesized that after the ß2-blockade ventilation increased in excess to CO2 output and this was further enhanced by interstitial edema. METHODS AND RESULTS: 22 healthy males took part in the study. On day 1, spirometry, lung diffusion for carbon monoxide (DLCO) including its subcomponents DM and capillary volume (VCap), and cardiopulmonary exercise test were performed. On day 2, these tests were repeated after rapid 25 ml/kg saline infusion. Then, in random order 11 subjects were assigned to oral treatment with Carvedilol (CARV) and 11 to Bisoprolol (BISOPR). When heart rate fell at least by 10 beats·min(-1), the tests were repeated before (day 3) and after saline infusion (day 4). CARV but not BISOPR, decreased DM (-13 ± 7%, p = 0.001) and increased VCap (+20 ± 22%, p = 0.016) and VE/VCO2 slope (+12 ± 8%, p<0.01). These changes further increased after saline: -18 ± 13% for DM (p<0.01), +44 ± 28% for VCap (p<0.001), and +20 ± 10% for VE/VCO2 slope (p<0.001). CONCLUSIONS: These findings support the hypothesis that in humans in vivo the ß2-alveolar receptors contribute to control alveolar fluid clearance and that interstitial lung fluid may trigger exercise hyperventilation.