Thoracic ultrasound use in hospitalized and ambulatory adult patients: a quantitative picture.

INTRODUCTION AND OBJECTIVES: Thoracic ultrasound (TUS) has been established as a powerful diagnostic and monitoring tool in the Intensive Care Unit (ICU). However, studies outside the critical care setting are scarce. The aim of this study was to investigate the value of TUS for hospitalized or ambulatory community patients. MATERIALS AND METHODS: This was a retrospective study conducted from 2016 to 2020 in the TUS clinic at Heraklion University Hospital. TUS examination was performed using a standard ultrasound machine (EUB HITACHI 8500), and a high-frequency microconvex probe (5-8 MHz). Patients had been referred by their primary physician to address a range of different questions. The various respiratory system entities were characterised according to internationally established criteria. RESULTS: 762 TUS studies were performed on 526 patients due to underlying malignancy (n = 376), unexplained symptoms/signs (n = 53), pregnancy related issues (n = 42), evaluation of abnormal findings in X-ray (n = 165), recent surgery/trauma (n = 23), recent onset respiratory failure (n = 12), acute respiratory infection (n = 66) and underlying non-malignant disease (n = 25). Pleural effusion was the commonest pathologic entity (n = 610), followed by consolidation (n = 269), diaphragmatic dysfunction/paradox (n = 174) and interstitial syndrome (n = 53). Discrepancies between chest X-ray and ultrasonographic findings were demonstrated in 96 cases. The TUS findings guided invasive therapeutic management in 448 cases and non-invasive management in 43 cases, while follow-up monitoring was decided in 271 cases. CONCLUSIONS: This study showed that TUS can identify the most common respiratory pathologic entities encountered in hospitalized and community ambulatory patients, and is especially useful in guiding the decision making process in a diverse group of patients.

Sleep quality in survivors of critical illness.

PURPOSE: There is limited data regarding the sleep quality in survivors of critical illness, while the time course of the sleep abnormalities observed after ICU discharge is not known. The aim of this study was to assess sleep quality and the time course of sleep abnormalities in survivors of critical illness. METHODS: Eligible survivors of critical illness without hypercapnia and hypoxemia were evaluated within 10 days (1st evaluation, n = 36) and at 6 months after hospital discharge (2nd evaluation, n = 29). At each visit, all patients underwent an overnight full polysomnography and completed health-related quality of life questionnaires (HRQL). Lung function and electro-diagnostic tests (ED) were performed in 24 and 11 patients, respectively. RESULTS: At 1st evaluation, sleep quality and HRQL were poor. Sleep was characterised by high percentages of N1, low of N3 and REM stages, and high apnea-hypopnea index (AHI, events/h). Twenty-two out of 36 patients (61%) exhibited AHI ≥ 15 (21 obstructive, 1 central). None of the patients' characteristics, including HRQL and lung function, predicted the occurrence of AHI ≥ 15. At 6 months, although sleep quality remained poor (high percentages of N1 and low of REM), sleep architecture had improved as indicated by the significant increase in N3 [4.2% (0-12.5) vs. 9.8% (3.0-20.4)] and decrease in AHI [21.5 (6.5-29.4) vs. 12.8 (4.7-20.4)]. HRQL improved slightly but significantly at 6 months. Neither the changes in HRQL nor in lung function tests were related to these of sleep architecture. Six out of eight patients with abnormal ED at 1st evaluation continued to exhibit abnormal results at 6 months. CONCLUSIONS: Survivors of critical illness exhibited a high prevalence of obstructive sleep-disordered breathing and poor sleep architecture at hospital discharge, which slightly improved 6 months later, indicating that reversible factors are partly responsible for these abnormalities.

Nutrition Adherence in Critically Ill Patients; How is nutritional intake within the 1st week of hospitalization affecting the patient's Outcome?

Nutritional requirements vary during a patient's stay in the Intensive Care Unit (ICU) and their calculation can be relatively complex. During ICU stay nutrition requirements are rarely met, especially during the initial days of the hospitalization. Studies have shown that poor nutrition is associated with adverse patient outcome. This study examines for correlation between poor nutrition (calories, proteins, lipids and micronutrients) during the 1st week of ICU stay and adverse patient outcome. Nutritional adherence effect is examined on groups of patients, such as patients with high BMI that receive low nutrition and critically ill males. Regarding the latter analysis, an accuracy rate of 76.4% was achieved when classifying the critically ill males towards their outcome. The results of this work could contribute to the development of smart alarms in the ICU.

Clinical factors affecting costs in patients receiving systemic antifungal therapy in intensive care units in Greece: Results from the ESTIMATOR study.

Invasive fungal infections are common in intensive care units (ICUs) but there is a great variability in factors affecting costs of different antifungal treatment strategies in clinical practice. To determine factors affecting treatment cost in adult ICU patients with or without documented invasive fungal infection receiving systemic antifungal therapy (SAT) we have performed a prospective, multicentre, observational study enrolling patients receiving SAT in participating ICUs in Greece. During the study period, 155 patients received SAT at 14 participating ICUs: 37 (23.9%) for proven fungal infection before treatment began, 10 (6.5%) prophylactically, 77 (49.7%) empirically and 31 (20.0%) pre-emptively; 66 patients receiving early SAT (55.9%) were subsequently confirmed to have proven infection with Candida spp. (eight while on treatment). The most frequently used antifungal drugs were echinocandins (89/155; 57.4%), fluconazole (31/155; 20%) and itraconazole (20/155; 12.9%). Mean total cost per patient by SAT strategy was €20 458 (proven), €15 054 (prophylaxis), €23 594 (empiric) and €22 184 (pre-emptive). Factors associated with significantly increased cost were initial treatment failure, length of stay (LOS) in ICU before starting SAT (i.e. from admission until treatment start), fever and proven candidaemia (all P≤.05). CONCLUSION: Early administration of antifungal drugs was not a substantial component of total hospital costs. However, there was a significant adverse impact on costs with increasing LOS in febrile patients in ICU for whom diagnosis of fungaemia was delayed before starting SAT, and with initial treatment failure. Awareness of potential candidaemia and initiation of pre-emptive or empirical strategy as early appropriate treatment may improve ICU patient outcomes while reducing direct medical costs.

Multiparametric modeling of the ineffective efforts in assisted ventilation within an ICU.

In the context of assisted ventilation in ICU, it is of vital importance to keep a high synchronization between the patient's attempt to breath and the assisted ventilation event, so that the patient receives the ventilation support requested. In this work, experimental equipment is employed, which allows for unobtrusive and continuous monitoring of a multiple relevant bioparameters. These are meant to guide the medical professionals in appropriately adapting the treatment and fine-tune the ventilation. However, synchronization phenomena of different origin (neurological, mechanical, ventilation parameters) may occur, which vary among patients, and during the course of monitoring of a single patient, the timely recognition of which is challenging even for experts. The dynamics and complex causal relations among bioparameters and the ventilation synchronization are not well studied. The purpose of this work is to elaborate on a methodology toward modeling the ventilation synchronization failures based on the evolution of monitored bioparameters. Principal component analysis is employed for the transformation into a small number of features and the investigation of repeating patterns and clusters within measurements. Using these features, nonlinear prediction models based on support vector machines regression are explored, in terms of what past knowledge is required and what is the future horizon that can be predicted. The proposed model shows good correlation (over 0.74) with the actual outputs, constituting an encouraging step toward understanding of ICU ventilation dynamic phenomena.

Ineffective efforts in ICU assisted ventilation: Exploring causalities via multiscale analysis.

Intensive Care Unit (ICU) is a data intensive environment, requiring continuous monitoring of patient's physiology and response to treatment. In assisted ventilation, where patient effort that triggers the ventilator and there is need for patient-ventilator coupling, attention is required in cases where patient's effort that doesn't trigger the ventilator at all. When synchronization between the patient's attempt to breath and the assisted ventilation event is lost, an ineffective effort (IE) event takes place. A series of relevant bioparameters continuously monitored, are meant to guide the medical professionals in appropriately adapting the operation and treatment, in order to minimize IEs. The purpose of this work is to investigate the causal relations between physiological or ventilation parameters and IE events. A multiscale approach is proposed, based on wavelet similarity and localized phase relationship. The proposed method indicates the existence of distinct frequency zones correlated with the IE experienced by the patient.

(137)Cs vertical distribution at the deep basins of the North and Central Aegean Sea, Greece.

Large volume seawater samples were collected for the determination of (137)Cs concentration along with depth in the deep basins of North and Central Aegean Sea. The vertical (137)Cs distribution showed maximum concentration at the bottom of the basins, while the minimum values corresponded to the intermediate layer, where Levantine water exists. The surface (137)Cs activity is found to lie between the two limits and is originated from the Black Sea waters. The typical oceanographic advection-diffusion balance model is modified to a diffusion-settling-decay balance model to better understand the vertical distribution and variation of the (137)Cs concentration in the deep basins. In addition, the diffusivity of each basin, as well as the settling speed of particulate (137)Cs is also estimated. The results are compared with theoretical approach as well as with previous data.

Patient-ventilator synchrony and sleep quality with proportional assist and pressure support ventilation.

OBJECTIVE: To examine patient-ventilator asynchrony and sleep quality in non-sedated critically ill patients ventilated with proportional assist ventilation with load adjustable gain factors (PAV+) and pressure support (PSV). METHODS: This was a randomized crossover physiological study conducted in an adult ICU at a tertiary hospital. Patients who exhibited patient-ventilator asynchrony on PSV were selected. Polysomnography was performed in these patients over 24 h, during which respiratory variables were continuously recorded. During the study period, each patient was randomized to receive alternating 4-h periods of PSV and PAV+ equally distributed during the day and night. Sleep architecture was analyzed manually using predetermined criteria. Patient-ventilator asynchrony was evaluated breath by breath using the flow-time and airway pressure-time waveforms. RESULTS: Fourteen patients were studied. The majority (85.7 %) had either acute exacerbation of COPD as admission diagnosis or COPD as comorbidity. During sleep, compared to PSV, PAV+ significantly reduced the patient-ventilator asynchrony events per hour of sleep [5 (1-17) vs. 40 (4-443), p = 0.02, median (25-75th interquartile range)]. Compared to PSV, PAV+ was associated with slightly but significantly greater sleep fragmentation [18.8 (13.1-33.1) versus 18.1 (7.0-22.8) events/h, p = 0.01] and less REM sleep [0.0 % (0.0-8.4) vs. 5.8 % (0.0-21.9), p = 0.02). CONCLUSIONS: PAV+ failed to improve sleep in mechanically ventilated patients despite the fact that this mode was associated with better synchrony between the patient and ventilator. These results do not support the hypothesis that patient-ventilator synchrony plays a central role in determining sleep quality in this group of patients.

Respiratory muscle dysfunction in COPD: from muscles to cell.

Respiratory muscle dysfunction is a cardinal feature of acute and chronic respiratory failure in COPD. Diaphragm and accessory inspiratory muscles face increased load due to increased lung resistance and elastance, as well as increased ventilatory demands. Concomitantly, the capacity of the inspiratory muscles to generate pressure is decreased due to mechanical disadvantage imposed by hyperinflation. Additionally, inflammation and oxidative stress impair muscle fiber specific force generation and increase diaphragm susceptibility to sarcomer disruption during acute inspiratory loading. In response to this increased load diaphragm presents unique adaptations in its cellular structure and passive and contractile mechanical properties, and displays a more efficient metabolic armamentarium. A shift of muscle fiber type towards slow-twitch, oxidative type I fibers, which are more fatigue-resistant, increases diaphragmatic endurance but protein degradation and a significant reduction in myosin content decrease its force generating capacity. Furthermore, diaphragm adapts to chronic hyperinflation by sarcomere deletion so that its overall length is shortened, in an attempt to preserve optimum force-length relationship. Adaptation however may not be complete, or may be overwhelmed by pathophysiologic derangements during exercise or acute exacerbations, leading to obvious "dysfunction" of the respiratory muscles, and if sustained, ultimately to muscle fatigue and respiratory pump failure.

Underwater in situ measurements of radionuclides in selected submarine groundwater springs, Mediterranean Sea.

The application of the in situ measurement system 'KATERINA' for monitoring of radon progenies in submarine groundwater discharge (SGD) was investigated at different locations in the Mediterranean Sea (Chalkida, Stoupa, Korfos and Cabbé). At Chalkida and Stoupa radon progenies concentration exhibited almost constant values of 1.2 ± 0.1 and 2.5 ± 0.2 Bq l(-1), respectively. At Korfos these activities ranged between 1.4 ± 0.1 and 2.3 ± 0.2 Bq l(-1) exhibiting inverse relationship with salinity. At Cabbé the in situ measured data were compared with radon measurements obtained by liquid scintillation counter. The system also resolved radon progeny variations of SGD on time scales above 1 h. The radioactivity levels of radon progenies from all sites were found considerably lower (approximately 2 orders of magnitude) than the commonly accepted limits for radon in drinking water.

Sleep during proportional-assist ventilation with load-adjustable gain factors in critically ill patients.

BACKGROUND: Proportional-assist ventilation with load-adjustable gain factors (PAV+) automatically adjusts the flow and volume assist to represent constant fractions of resistance and elastance of the respiratory system, respectively. Resistance and elastance are calculated at random intervals of 4-10 breaths, by applying a 300 ms pause maneuver at the end of selected inspirations. OBJECTIVES: To determine whether the large number of end-inspiratory occlusions during PAV+ operation influences sleep quality in critically ill patients who exhibited good patient-ventilator synchrony during pressure support (PS, baseline). METHODS: One and two nights' polysomnography was performed in sedated (protocol A, n=11) and non-sedated (protocol B, n=9) patients, respectively, while respiratory variables were continuously recorded. In each protocol the patients were ventilated with PAV+ and PS at two levels of assist (baseline and high). RESULTS: In both protocols sleep quality did not differ between the modes of support or the assist levels. In sedated patients sleep efficiency was slightly but significantly higher with PAV+ than with high PS, while it did not differ between modes in non-sedated patients. The two modes of support had comparable effects on respiratory variables. Independent of the mode of support and particularly at high assist, a significant proportion of patients developed periodic breathing during sleep (27% in protocol A and 44% in protocol B). CONCLUSION: In patients exhibiting good patient-ventilator synchrony during PS, the large number of short-term end-inspiratory occlusions with PAV+ operation did not adversely influence sleep quality. With both modes high assist may cause unstable breathing during sleep.

Influence of respiratory efforts on b2-agonist induced bronchodilation in mechanically ventilated COPD patients: a prospective clinical study.

BACKGROUND: Several in vitro studies have shown that at similar tidal volume (VT), bronchodilator delivery to target sites is significantly lower during controlled mechanical ventilation (CMV) than that during simulated spontaneous breathing. However, the influence of active respiratory efforts on the magnitude of b2-agonist induced bronchodilation in mechanically ventilated patients has not been examined. OBJECTIVE: To examine the influence of controlled and assisted modes of ventilatory support on the bronchodilative effect induced by b2-agonists administered with a metered dose inhaler (MDI) and a spacer device in a homogeneous group of mechanically ventilated patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). METHODS: Prospective clinical study. Ten mechanically ventilated patients with acute exacerbation of COPD were prospectively randomized to receive 4 puffs of salbutamol (S, 100 micro g/puff) either with volume-controlled (VC) or pressure-support (PS) ventilation. On PS the pressure level was such that VT was comparable between ventilatory modes. After a 6-h washout period, patients were crossed-over to receive the drug by the alternative mode of ventilation. Static and dynamic airway pressures, minimum (R(int)) and maximum (R(rs)) inspiratory resistance, the difference between R(rs) and R(int) (DeltaR), end-inspiratory static compliance of the respiratory system (C(rs)), intrinsic positive end-expiratory pressure (PEEP(i)) and heart rate (HR) were measured before and at 15, 30, 60, 120, 180 and 240 min after S administration. RESULTS: S caused a significant decrease in dynamic and static airway pressures, PEEP(i), R(int) and R(rs). These changes were not influenced by the ventilatory mode and were evident at 15, 30, 60 and 120 min after S. HR, C(rs) and DeltaR did not change after S administration. CONCLUSIONS: Considering the use of propofol with its presumed bronchodilative properties as a shortcoming of our study, it is concluded that the magnitude of bronchodilation induced by salbutamol delivered by an MDI and a spacer device in mechanically ventilated COPD patients is not affected by the presence or absence of active respiratory efforts.