Timing of inspiratory muscle activity detected from airway pressure and flow during pressure support ventilation: the waveform method.

BACKGROUND: Whether respiratory efforts and their timing can be reliably detected during pressure support ventilation using standard ventilator waveforms is unclear. This would give the opportunity to assess and improve patient-ventilator interaction without the need of special equipment. METHODS: In 16 patients under invasive pressure support ventilation, flow and pressure waveforms were obtained from proximal sensors and analyzed by three trained physicians and one resident to assess patient's spontaneous activity. A systematic method (the waveform method) based on explicit rules was adopted. Esophageal pressure tracings were analyzed independently and used as reference. Breaths were classified as assisted or auto-triggered, double-triggered or ineffective. For assisted breaths, trigger delay, early and late cycling (minor asynchronies) were diagnosed. The percentage of breaths with major asynchronies (asynchrony index) and total asynchrony time were computed. RESULTS: Out of 4426 analyzed breaths, 94.1% (70.4-99.4) were assisted, 0.0% (0.0-0.2) auto-triggered and 5.8% (0.4-29.6) ineffective. Asynchrony index was 5.9% (0.6-29.6). Total asynchrony time represented 22.4% (16.3-30.1) of recording time and was mainly due to minor asynchronies. Applying the waveform method resulted in an inter-operator agreement of 0.99 (0.98-0.99); 99.5% of efforts were detected on waveforms and agreement with the reference in detecting major asynchronies was 0.99 (0.98-0.99). Timing of respiratory efforts was accurately detected on waveforms: AUC for trigger delay, cycling delay and early cycling was 0.865 (0.853-0.876), 0.903 (0.892-0.914) and 0.983 (0.970-0.991), respectively. CONCLUSIONS: Ventilator waveforms can be used alone to reliably assess patient's spontaneous activity and patient-ventilator interaction provided that a systematic method is adopted.

Intracranial Pressure Monitoring in Poor-Grade Patients with Aneurysmal Subarachnoid Hemorrhage Treated by Coiling.

OBJECTIVE: The main objective of the present study was to analyze the intracranial pressure (ICP) and cerebral perfusion pressure (CPP) changes during coiling. We also evaluated the prevalence of rebleeding and outcomes for patients monitored before and after coiling. METHODS: Ninety-nine consecutive poor-grade patients with aneurysmal subarachnoid hemorrhage (aSAH; World Federation of Neurological Surgeons grade IV and V) were enrolled in our prospective observational study. For 31 patients, ICP and CPP monitoring was started immediately after the diagnosis of aSAH, and the values were recorded every 15 minutes during coiling (early ICP group). For 68 patients, ICP and CPP monitoring began after coiling (late ICP group). The outcomes were evaluated at 90 days using the modified Rankin scale. RESULTS: At the beginning of coiling, the ICP was >20 mm Hg in 10 patients (35.7%). The median ICP was 18 mm Hg (range, 5-60 mm Hg). The CPP was <60 mm Hg in 6 patients (24%). The median CPP was 70 mm Hg (range, 30-101 mm Hg). Despite medical treatment and/or cerebrospinal fluid drainage, 51.6% of the patients monitored during coiling had at least one episode of intracranial hypertension (defined as ICP >20 mm Hg), and 51.6% had at least one episode of reduced CPP (defined as CPP <60 mm Hg). Early monitoring (before aneurysm repair) was not associated with rebleeding. At 90 days, the functional recovery was better in the early ICP group (P = 0.004). CONCLUSIONS: During coiling, patients with poor-grade aSAH can experience episodes of intracranial hypertension and reduced CPP. Early and appropriate treatment of elevated ICP was not associated with rebleeding and might have improved the outcomes.

End-tidal carbon dioxide (ETCO2) and ventricular fibrillation amplitude spectral area (AMSA) for shock outcome prediction in out-of-hospital cardiac arrest. Are they two sides of the same coin?

AIM: Ventricular fibrillation amplitude spectral area (AMSA) and end-tidal carbon dioxide (ETCO2) are predictors of shock success, understood as restoration of an organized rhythm, and return of spontaneous circulation (ROSC). However, little is known about their combined use. We aimed to assess the prediction accuracy when combined, and to clarify if they are correlated in out of hospital cardiac arrest' victims. MATERIALS AND METHODS: Records acquired by external defibrillators in out-of-hospital cardiac arrest patients of the Lombardia Cardiac Arrest registry were processed. The 1-min pre-shock ETCO2 median value (METCO2) was computed from the capnogram and AMSA (2-48 mV.Hz range) computed applying the Fast Fourier Transform to a 2-second pre-shock filtered ECG interval (0.5-30 Hz). Support Vector Machine (SVM) predictive models based on METCO2, AMSA and their combination were fit; results were given as the area under the curve (AUC) of the receiver operating characteristic (ROC) curves. RESULTS: We considered 112 patients with 391 shocks delivered. METCO2 and AMSA were predictors of shock success [AUC (IQR) of the ROC curve: 0.59 (0.56-0.62); 0.68 (0.65-0.72), respectively] and of ROSC [0.56 (0.53-0.59); 0.74 (0.71-0.78),]. Their combination in a SVM model increased the accuracy for predicting shock success [AUC (IQR) of the ROC curve: 0.71 (0.68-0.75)] and ROSC [0.77 (0.73-0.8)]. AMSA and METCO2 were significantly correlated only in patients who achieved ROSC (rho = 0.33 p = 0.03). CONCLUSIONS: AMSA and ETCO2 predict shock success and ROSC after every shock, and their predictive power increases if combined. Notably, they were correlated only in patients who achieved ROSC.

Impact of Coronavirus Disease 2019 Pandemic on Crowding: A Call to Action for Effective Solutions to "Access Block".

INTRODUCTION: Healthcare patterns change during disease outbreaks and pandemics. Identification of modified patterns is important for future preparedness and response. Emergency department (ED) crowding can occur because of the volume of patients waiting to be seen, which results in delays in patient assessment or treatment and impediments to leaving the ED once treatment is complete. Therefore, ED crowding has become a growing problem worldwide and represents a serious barrier to healthcare operations. METHODS: This observational study was based on a retrospective review of the epidemiologic and clinical records of patients who presented to the Foundation IRCCS Policlinic San Matteo in Pavia, Italy, during the coronavirus disease 2019 (COVID-19) outbreak (February 21-May 1, 2020, pandemic group). The methods involved an estimation of the changes in epidemiologic and clinical data from the annual baseline data after the start of the COVID-19 pandemic. RESULTS: We identified reduced ED visits (180 per day in the control period vs 96 per day in the pandemic period; P < 0.001) during the COVID-19 pandemic, irrespective of age and gender, especially for low-acuity conditions. However, patients who did present to the ED were more likely to be hemodynamically unstable, exhibit abnormal vital signs, and more frequently required high-intensity care and hospitalization. During the pandemic, ED crowding dramatically increased primarily because of an increased number of visits by patients with high-acuity conditions, changes in patient management that prolonged length of stay, and increased rates of boarding, which led to the inability of patients to gain access to appropriate hospital beds within a reasonable amount of time. During the pandemic, all crowding output indices increased, especially the rates of boarding (36% vs 57%; P < 0.001), "access block" (24% vs 47%; P < 0.001), mean boarding time (640 vs 1,150 minutes [min]; P 0.001), mean "access block" time (718 vs 1,223 min; P < 0.001), and "access block" total time (650,379 vs 1,359,172 min; P < 0.001). CONCLUSION: Crowding in the ED during the COVID-19 pandemic was due to the inability to access hospital beds. Therefore, solutions to this lack of access are required to prevent a recurrence of crowding due to a new viral wave or epidemic.

Carbon Dioxide Elimination During Veno-Venous Extracorporeal Membrane Oxygenation Weaning: A Pilot Study.

Veno-venous extracorporeal membrane oxygenation (V-V ECMO) represents a component of the treatment strategy for severe respiratory failure. Clinical evidence on the management of the lung during V-V ECMO are limited just as the consensus regarding timing of weaning. The monitoring of the carbon dioxide (CO2) removal (V'CO2TOT) is subdivided into two components: the membrane lung (ML) and the native lung (NL) are both taken into consideration to evaluate the improvement of the function of the lung and to predict the time to wean off ECMO. We enrolled patients with acute respiratory distress syndrome (ARDS). The V'CO2NL ratio (V'CO2NL/V'CO2TOT) value was calculated based on the distribution of CO2 between the NL and the ML. Of 18 patients, 15 were successfully weaned off of V-V ECMO. In this subgroup, we observed a significant increase in the V'CO2NL ratio comparing the median values of the first and last quartiles (0.32 vs. 0.53, p = 0.0045), without observing any modifications in the ventilation parameters. An increase in the V'CO2NL ratio, independently from any change in ventilation could, despite the limitations of the study, indicate an improvement in pulmonary function and may be used as a weaning index for ECMO.

Use of critical care resources during the first 2 weeks (February 24-March 8, 2020) of the Covid-19 outbreak in Italy.

BACKGROUND: A Covid-19 outbreak developed in Lombardy, Veneto and Emilia-Romagna (Italy) at the end of February 2020. Fear of an imminent saturation of available ICU beds generated the notion that rationing of intensive care resources could have been necessary. RESULTS: In order to evaluate the impact of Covid-19 on the ICU capacity to manage critically ill patients, we performed a retrospective analysis of the first 2 weeks of the outbreak (February 24-March 8). Data were collected from regional registries and from a case report form sent to participating sites. ICU beds increased from 1545 to 1989 (28.7%), and patients receiving respiratory support outside the ICU increased from 4 (0.6%) to 260 (37.0%). Patients receiving respiratory support outside the ICU were significantly older [65 vs. 77 years], had more cerebrovascular (5.8 vs. 13.1%) and renal (5.3 vs. 10.0%) comorbidities and less obesity (31.4 vs. 15.5%) than patients admitted to the ICU. PaO2/FiO2 ratio, respiratory rate and arterial pH were higher [165 vs. 244; 20 vs. 24 breath/min; 7.40 vs. 7.46] and PaCO2 and base excess were lower [34 vs. 42 mmHg; 0.60 vs. 1.30] in patients receiving respiratory support outside the ICU than in patients admitted to the ICU, respectively. CONCLUSIONS: Increase in ICU beds and use of out-of-ICU respiratory support allowed effective management of the first 14 days of the Covid-19 outbreak, avoiding resource rationing.

Mild head trauma in elderly patients: experience of an emergency department.

INTRODUCTION: We evaluated the risk profile of elderly patients who came to the emergency department for mild head trauma. The primary goal was to determine the difference in the incidence of posttraumatic intracranial hemorrhage (ICH) after minor head injury (MHI). The secondary objective was to assess worse outcome, such as: hospitalization rate, rate of re-admission, need of neurosurgery. We also assess the admission process times and length of hospital stay. The ultimate goal was to optimize the diagnostic-observational management of minor head trauma in elderly patients. MATERIAL AND METHODS: We evaluated all patients with MHI who came to our emergency department during 2017 and 2018. All patients underwent computed tomography. RESULTS: We enrolled 2325 patients, of whom 1094 were 75 years of age or older. The population was divided into two categories according to age: The "elderly population" was 75 or older, and the younger patients were younger than 75. The elderly population, in comparison with the younger patients, had a higher rate of ICH (12.1% versus 5.1%), a higher hospitalization rate (11.7% versus 5.5%), and a higher rate of readmission within 30 days (6.8% versus 3.2%). The elderly population also had longer admission process times (8 h, 25 min, versus 4 h, 09 min) and longer lengths of hospital stay (9 h, 41 min, versus 5 h, 29 min). Of the younger patients, 92% (versus 41% of the elderly population) did not take any drugs, 6% (versus 39%) were receiving antiplatelet therapy, 1% (versus 13%) took vitamin K antagonists, and 1% (versus 7%) took oral direct-acting anticoagulants. Logistic regression models revealed that a 1-year increase in age raised the risk of bleeding by 2% on average; this finding was statistically significant (odds ratio [OR], 1023/year, p < 0.001). The rate of ICH increased significantly after the age of 75, by 180% (OR, 2.82; p < 0.001). CONCLUSIONS: These data suggest that age is an independent risk factor for ICH, whereby the age of 75 entails a 180% increase in the risk of bleeding.

Risk Factors Associated With Mortality Among Patients With COVID-19 in Intensive Care Units in Lombardy, Italy.

Importance: Many patients with coronavirus disease 2019 (COVID-19) are critically ill and require care in the intensive care unit (ICU). Objective: To evaluate the independent risk factors associated with mortality of patients with COVID-19 requiring treatment in ICUs in the Lombardy region of Italy. Design, Setting, and Participants: This retrospective, observational cohort study included 3988 consecutive critically ill patients with laboratory-confirmed COVID-19 referred for ICU admission to the coordinating center (Fondazione IRCCS [Istituto di Ricovero e Cura a Carattere Scientifico] Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy) of the COVID-19 Lombardy ICU Network from February 20 to April 22, 2020. Infection with severe acute respiratory syndrome coronavirus 2 was confirmed by real-time reverse transcriptase-polymerase chain reaction assay of nasopharyngeal swabs. Follow-up was completed on May 30, 2020. Exposures: Baseline characteristics, comorbidities, long-term medications, and ventilatory support at ICU admission. Main Outcomes and Measures: Time to death in days from ICU admission to hospital discharge. The independent risk factors associated with mortality were evaluated with a multivariable Cox proportional hazards regression. Results: Of the 3988 patients included in this cohort study, the median age was 63 (interquartile range [IQR] 56-69) years; 3188 (79.9%; 95% CI, 78.7%-81.1%) were men, and 1998 of 3300 (60.5%; 95% CI, 58.9%-62.2%) had at least 1 comorbidity. At ICU admission, 2929 patients (87.3%; 95% CI, 86.1%-88.4%) required invasive mechanical ventilation (IMV). The median follow-up was 44 (95% CI, 40-47; IQR, 11-69; range, 0-100) days; median time from symptoms onset to ICU admission was 10 (95% CI, 9-10; IQR, 6-14) days; median length of ICU stay was 12 (95% CI, 12-13; IQR, 6-21) days; and median length of IMV was 10 (95% CI, 10-11; IQR, 6-17) days. Cumulative observation time was 164 305 patient-days. Hospital and ICU mortality rates were 12 (95% CI, 11-12) and 27 (95% CI, 26-29) per 1000 patients-days, respectively. In the subgroup of the first 1715 patients, as of May 30, 2020, 865 (50.4%) had been discharged from the ICU, 836 (48.7%) had died in the ICU, and 14 (0.8%) were still in the ICU; overall, 915 patients (53.4%) died in the hospital. Independent risk factors associated with mortality included older age (hazard ratio [HR], 1.75; 95% CI, 1.60-1.92), male sex (HR, 1.57; 95% CI, 1.31-1.88), high fraction of inspired oxygen (Fio2) (HR, 1.14; 95% CI, 1.10-1.19), high positive end-expiratory pressure (HR, 1.04; 95% CI, 1.01-1.06) or low Pao2:Fio2 ratio (HR, 0.80; 95% CI, 0.74-0.87) on ICU admission, and history of chronic obstructive pulmonary disease (HR, 1.68; 95% CI, 1.28-2.19), hypercholesterolemia (HR, 1.25; 95% CI, 1.02-1.52), and type 2 diabetes (HR, 1.18; 95% CI, 1.01-1.39). No medication was independently associated with mortality (angiotensin-converting enzyme inhibitors HR, 1.17; 95% CI, 0.97-1.42; angiotensin receptor blockers HR, 1.05; 95% CI, 0.85-1.29). Conclusions and Relevance: In this retrospective cohort study of critically ill patients admitted to ICUs in Lombardy, Italy, with laboratory-confirmed COVID-19, most patients required IMV. The mortality rate and absolute mortality were high.

Radiographic findings in 240 patients with COVID-19 pneumonia: time-dependence after the onset of symptoms.

OBJECTIVE: To analyze the most frequent radiographic features of COVID-19 pneumonia and assess the effectiveness of chest X-ray (CXR) in detecting pulmonary alterations. MATERIALS AND METHODS: CXR of 240 symptomatic patients (70% male, mean age 65 ± 16 years), with SARS-CoV-2 infection confirmed by RT-PCR, was retrospectively evaluated. Patients were clustered in four groups based on the number of days between symptom onset and CXR: group A (0-2 days), 49 patients; group B (3-5), 75 patients; group C (6-9), 85 patients; and group D (> 9), 31 patients. Alteration's type (reticular/ground-glass opacity (GGO)/consolidation) and distribution (bilateral/unilateral, upper/middle/lower fields, peripheral/central) were noted. Statistical significance was tested using chi-square test. RESULTS: Among 240 patients who underwent CXR, 180 (75%) showed alterations (group A, 63.3%; group B, 72%; group C, 81.2%; group D, 83.9%). GGO was observed in 124/180 patients (68.8%), reticular alteration in 113/180 (62.7%), and consolidation in 71/180 (39.4%). Consolidation was significantly less frequent (p < 0.01). Distribution among groups was as follows: reticular alteration (group A, 70.9%; group B, 72.2%; group C, 57.9%; group D, 46.1%), GGO (group A, 67.7%; group B, 62.9%; group C, 71%; group D, 76.9%), and consolidation (group A, 35.5%; group B, 31.4%; group C, 47.8%; group D, 38.5%). Alterations were bilateral in 73.3%. Upper, middle, and lower fields were involved in 36.7%, 79.4%, and 87.8%, respectively. Lesions were peripheral in 49.4%, central in 11.1%, or both in 39.4%. Upper fields and central zones were significantly less involved (p < 0.01). CONCLUSIONS: The most frequent lesions in COVID-19 patients were GGO (intermediate/late phase) and reticular alteration (early phase) while consolidation gradually increased over time. The most frequent distribution was bilateral, peripheral, and with middle/lower predominance. Overall rate of negative CXR was 25%, which progressively decreased over time. KEY POINTS: • The predominant lung changes were GGO and reticular alteration, while consolidation was less frequent. • The typical distribution pattern was bilateral, peripheral, or both peripheral and central and involved predominantly the lower and middle fields. • Chest radiography showed lung abnormalities in 75% of patients with confirmed SARS-CoV-2 infection, range varied from 63.3 to 83.9%, respectively, at 0-2 days and > 9 days from the onset of symptoms.

Lung Ultrasound in Patients with Acute Respiratory Failure Reduces Conventional Imaging and Health Care Provider Exposure to COVID-19.

Lung ultrasound gained a leading position in the last year as an imaging technique for the assessment and management of patients with acute respiratory failure. In coronavirus disease 2019 (COVID-19), its role may be of further importance because it is performed bedside and may limit chest X-ray and the need for transport to radiology for computed tomography (CT) scan. Since February 21, we progressively turned into a coronavirus-dedicated intensive care unit and applied an ultrasound-based approach to avoid traditional imaging and limit contamination as much as possible. We performed a complete daily examination with lung ultrasound score computation and systematic search of complications (pneumothorax, ventilator-associated pneumonia); on-duty physicians were free to perform CT or chest X-ray when deemed indicated. We compared conventional imaging exams performed in the first 4 wk of the COVID-19 epidemic with those in the same time frame in 2019: there were 84 patients in 2020 and 112 in 2019; 64 and 22 (76.2% vs. 19.6%, p < 0.001) had acute respiratory failure, respectively, of which 55 (85.9%) were COVID-19 in 2020. When COVID-19 patients in 2020 were compared with acute respiratory failure patients in 2019, the median number of chest X-rays was 1.0 (1.0-2.0) versus 3.0 (1.0-4.0) (p = 0.0098); 2 patients 2 (3.6%) versus 7 patients (31.8%) had undergone at least one thoracic CT scan (p = 0.001). A self-imposed ultrasound-based approach reduces the number of chest X-rays and thoracic CT scans in COVID-19 patients compared with patients with standard acute respiratory failure, thus reducing the number of health care providers exposed to possible contamination and sparing personal protective equipment.

Combined ultrasound-CT approach to monitor acute exacerbation of interstitial lung disease.

BACKGROUND: Lung ultrasound is a bedside non-irradiating tool for assessment and monitoring of lung diseases. A lung ultrasound score based on visualized artefacts allows reliable quantification of lung aeration, and is useful to monitor mechanical ventilation setting, fluid resuscitation and antibiotic response in critical care. In the context of interstitial lung diseases associated to connective tissue disorders, lung ultrasound has been integrated to computed tomography for diagnosis and follow-up monitoring of chronic lung disease progression. CASE PRESENTATION: This case describes a severe acute exacerbation of interstitial lung disease associated to dermatomyositis-polymyositis requiring prolonged extra-corporeal life support. Lung ultrasound score was performed daily and allowed monitoring and guiding both the need of advanced imaging as computed tomography and immunosuppressive therapy. CONCLUSIONS: This case suggests lung ultrasound may be a useful monitoring tool for the response to immunosuppressive therapy in acute severe rheumatic interstitial lung disease, where chest X-ray is poorly informative, and transportation is at high risk.

Trauma Coagulopathy and Its Outcomes.

Background and Objectives: Trauma coagulopathy begins at the moment of trauma. This study investigated whether coagulopathy upon arrival in the emergency room (ER) is correlated with increased hemotransfusion requirement, more hemodynamic instability, more severe anatomical damage, a greater need for hospitalization, and hospitalization in the intensive care unit (ICU). We also analyzed whether trauma coagulopathy is correlated with unfavorable indices, such as acidemia, lactate increase, and base excess (BE) increase. Material and Methods: We conducted a prospective, monocentric, observational study of all patients (n = 503) referred to the Department of Emergency and Acceptance, IRCCS Fondazione Policlinico San Matteo, Pavia, for major trauma from 1 January 2018 to 30 January 2019. Results: Of the 503 patients, 204 had trauma coagulopathy (group 1), whereas 299 patients (group 2) did not. Group 1 had a higher hemotransfusion rate than group 2. In group 1, 15% of patients showed hemodynamic instability compared with only 8% of group 2. The shock index (SI) distribution was worse in group 1 than in group 2. Group 1 was more often hypotensive, tachycardic, and with low oxygen saturation, and had a more severe injury severity score than group 2. In addition, 47% of group 1 had three or more body districts involved compared with 23% of group 2. The hospitalization rate was higher in group 1 than in group 2 (76% vs. 58%). The length of hospitalization was >10 days for 45% of group 1 compared with 28% of group 2. The hospitalization rate in the ICU was higher in group 1 than in group 2 (22% vs. 14.8%). The average duration of ICU hospitalization was longer in group 1 than in group 2 (12.5 vs. 9.78 days). Mortality was higher in group 1 than in group 2 (3.92% vs. 0.98%). Group 1 more often had acidemia and high lactates than group 2. Group 1 also more often had BE <-6. Conclusions: Trauma coagulopathy patients, upon arrival in the ER, have greater hemotransfusion (p = 0.016) requirements and need hospitalization (p = 0.032) more frequently than patients without trauma coagulopathy. Trauma coagulopathy seems to be more present in patients with a higher injury severity score (ISS) (p = 0.000) and a greater number of anatomical districts involved (p = 0.000). Head trauma (p = 0.000) and abdominal trauma (p = 0.057) seem related to the development of trauma coagulopathy. Males seem more exposed than females in developing trauma coagulopathy (p = 0.018). Upon arrival in the ER, the presence of tachycardia or alteration of SI and its derivatives can allow early detection of patients with trauma coagulopathy.

Myocardial localization of coronavirus in COVID-19 cardiogenic shock.

We describe the first case of acute cardiac injury directly linked to myocardial localization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a 69-year-old patient with flu-like symptoms rapidly degenerating into respiratory distress, hypotension, and cardiogenic shock. The patient was successfully treated with venous-arterial extracorporeal membrane oxygenation (ECMO) and mechanical ventilation. Cardiac function fully recovered in 5 days and ECMO was removed. Endomyocardial biopsy demonstrated low-grade myocardial inflammation and viral particles in the myocardium suggesting either a viraemic phase or, alternatively, infected macrophage migration from the lung.