Incidental Diagnosis of Left Pneumothorax Using a New Variant of the Lung Point Sign During Cardiac Ultrasound.

BACKGROUND: Pneumothorax is a common issue in the intensive care unit and emergency department, often diagnosed using lung ultrasound. The absence of lung sliding and the presence of the lung point sign are characteristic findings for pneumothorax. We describe a case of left pneumothorax diagnosed incidentally while performing a cardiac ultrasound through a new variant of the lung point sign. CASE REPORT: A 60-year-old patient with a medical history of diabetes, stroke, and right colon cancer underwent urgent surgical treatment for intestinal sub-occlusion. In the intensive care unit, the patient required mechanical ventilation due to shock unresponsive to fluid administration, and hemodynamic monitoring was performed using echocardiography. During systole in an apical four-chamber view, the abrupt vanishing of the heart was observed. When evaluating the tricuspid annular plane systolic excursion (TAPSE) using M-mode, the interposition of the stratosphere sign during mid-systole prevented the visualization of the TAPSE peak. Lung ultrasound revealed the absence of lung sliding and the presence of the lung point sign on the left side of the thorax, confirming the diagnosis of pneumothorax. A chest x-ray study further confirmed the diagnosis, and urgent drainage was performed. The patient showed improvement in hemodynamic and respiratory conditions and was successfully weaned from mechanical ventilation, and eventually discharged home. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: By incorporating the lung ultrasound findings, including this new variant of the lung point sign, into their diagnostic approach to pneumothorax, emergency physicians can promptly initiate appropriate intervention, such as chest tube insertion, leading to improved patient outcomes.

Assessment of Cheyne-Stokes respiration using diaphragmatic ultrasonography.

This case explores Cheyne-Stokes respiration (CSR), a breathing pattern common in heart failure and brain injury patients. Using diaphragmatic ultrasound, the study assesses a 74-year-old patient with heart failure exhibiting CSR during sleep. Diaphragmatic excursion patterns reveal the characteristic crescendo-decrescendo pattern of CSR.

Correlation between corrected carotid flow time and left ventricular outflow tract velocity-time integral using a novel technique.

BACKGROUND: Transthoracic echocardiography (TTE) is widely used for assessing patients in the intensive care unit, with cardiac output measurement being crucial for hemodynamic monitoring. This is achieved by measuring the velocity-time integral (VTI) of the left ventricular outflow tract (LVOT), which serves as a surrogate of stroke volume. However, conducting TTE in the critical care setting presents several challenges. Our primary objective was to investigate the relationship between carotid corrected flow time (cCFT) and LVOT VTI. Additionally, we aimed to determine the threshold cCFT value that reliably predicts a normal LVOT VTI. MATERIALS AND METHODS: This proof-of-concept study involves a post-hoc analysis from a diagnostic accuracy investigation conducted in a medical-surgical intensive care unit. We included patients admitted to the ICU from December 2021 to January 2022. We used a phased array transducer to measure the cCFT at the left supraclavicular fossa and the LVOT VTI in an apical 5-chamber view. RESULTS: We included 22 patients. The Spearman coefficient between LVOT VTI and cCFT was 0.82 (p < 0.0001). The area under the ROC curve for cCFT to predict LVOT VTI equal to or greater than 17 cm was 0.871 (95% CI 0.660-0.974). A cCFT exceeding 283 ms predicted LVOT VTI equal to or greater than 17 cm with a sensitivity of 93.3% (95% CI 68.1% to 99.8%) and specificity of 85.7% (95% CI 42.1% to 99.6%). CONCLUSION: The cCFT, measured using a novel technique with a phased array transducer, shows a strong correlation with LVOT VTI. Additionally, cCFT predicts a normal LVOT VTI with good sensitivity and specificity in critically ill patients. Larger studies are warranted to validate these findings.

Predicting mortality in severe Covid-19 Pneumonia: the role of right ventricular dysfunction.

PURPOSE: There is evidence that COVID-19 can have a clinically significant effect on the right ventricle (RV). Our objective was to enhance the efficiency of assessing RV dilation for diagnosing ACP by utilizing both linear measurements and qualitative assessment and its usefulness as an independent predictor of mortality. METHODS: This is an observational, retrospective and single-center study of the Intensive Care Unit of the Sanatorio de Los Arcos in Buenos Aires, Argentina from March 2020 to January 2022. All patients admitted with acute respiratory distress syndrome due to COVID-19 pneumonia (C-ARDS) on mechanical ventilation who were assessed by transthoracic echocardiography (TTE) were included. RESULTS: A total of 114 patients with C-ARDS requiring invasive mechanical ventilation were evaluated by echocardiography. 12.3% had RV dilation defined as a RV basal diameter greater than 41 mm, and 87.7% did not. Acute cor pulmonale (ACP) defined as RV dilation associated with paradoxical septal motion was found in 6.1% of patients. 7% had right ventricular systolic dysfunction according to qualitative evaluation. The different RV echocardiographic variables were studied with a logistic regression model as independent predictors of mortality. In the multivariate analysis, both the RV basal diameter and the presence of ACP showed to be independent predictors of in-hospital mortality with OR of 3.16 (95% CI 1.36-7.32) and 3.64 (95% CI 1.05-12.65) respectively. CONCLUSION: An increase in the RV basal diameter and the presence of ACP measured by TTE are independent predictors of in-hospital mortality in patients with C-ARDS.

Evaluating the Utility of Portal Vein Pulsatility Index for Detecting Fluid Unresponsiveness in the Intensive Care Unit.

OBJECTIVE: The primary aim of the authors' study was to evaluate the capacity of the portal vein pulsatility index (PVP) to detect fluid unresponsiveness in patients admitted to intensive care. DESIGN: This was a retrospective, diagnostic accuracy study SETTING: At a tertiary medical-surgical intensive care unit in Buenos Aires, Argentina. PARTICIPANTS: Patients were included during usual care in the intensive care unit, who were evaluated by ultrasonography for the flow of the portal vein, calculating their PVP prior to fluid expansion. INTERVENTIONS: Patients who exhibited an increase of <15% in left ventricle outflow tract velocity-time integral after receiving 500 mL of Ringer Lactate were considered non-responders to fluids. MEASUREMENTS AND MAIN RESULTS: The authors included a total of 63 patients between January 2022 and October 2022. The area under the receiver operating characteristic curve for PVP to predict fluid unresponsiveness was 0.708 (95% CI 0.580 to 0.816). A value of the PVP >32% predicted fluid unresponsiveness with a sensitivity of 30.8% (95% CI 17% to 47.6%) and specificity of 100% (95% CI 85.8 to 100). The positive predictive value was 100%, and the negative predictive value was 47.1% (95% CI 41.9% to 52.3%). CONCLUSIONS: Although PVP has limited value as the sole indicator for fluid management decisions, it can be used as a stopping rule or combined with other diagnostic tests to improve the accuracy of fluid responsiveness assessment.

Short Axis In-Plane Ultrasound-Guided Technique for Internal Jugular Vein Cannulation.

BACKGROUND: Real-time ultrasound (US)-guided venipuncture has become the standard of care due to its reduced complications and higher success rate. There are various techniques for US-guided cannulation of the internal jugular vein (IJV); the transversal and longitudinal views are the most widely used. There is a less commonly used technique that combines the benefits of both methods. DISCUSSION: Two main techniques for central line US-guided cannulation of the IJV are based on the location of the probe relative to the vessel and are known as the transversal view and the longitudinal view. The transversal view may make it difficult to identify the tip of the needle as it enters the vein, and the longitudinal view may not allow for visualization of surrounding structures. A third and less commonly used technique, the short axis in-plan view, aims to combine the benefits of both previous methods. In this technique, the entire needle can be tracked in real time as it enters the IJV, while also providing visualization of surrounding structures. CONCLUSIONS: The short axis in-plane view technique for central venous line placements allows for real-time US-guided needle venipuncture with simultaneous visualization of surrounding structures.

Cerebral circulatory arrest diagnosed with transoral Doppler ultrasonography.

We describe the case of a patient with malignant stroke in whom brain death was diagnosed by evaluating the neck vessels by transoral ultrasonography.

Utility of transcranial color-coded duplex sonography in diagnosis and monitoring of PICA aneurysm in subarachnoid hemorrhage.

This case describes the successful use of transcranial color-coded duplex sonography (TCCD) to diagnose a posterior circulation aneurysm in a patient with subarachnoid hemorrhage. A 33-year-old, was admitted to the ICU after a brain CT scan showed peritroncal subarachnoid hemorrhage. TCCD revealed a rounded image with color Doppler near the P1 portion of the right posterior cerebral artery, which was later confirmed to be a 4 mm aneurysm at the right posterior inferior cerebellar artery (PICA). The aneurysm was treated with coil exclusion and TCCD confirmed its disappearance post-treatment. While TCCD has limitations, including its inability to detect small aneurysms, it is a noninvasive diagnostic tool that provides real-time visualization of the brain and allows for follow-up evaluations. This case demonstrates the potential usefulness of TCCD in diagnosing cerebral aneurysms in patients with subarachnoid hemorrhage and for follow-up evaluations post-treatment.

Ultrasound-guided cerebral resuscitation in patients with severe traumatic brain Injury.

Traumatic brain injury (TBI) is a worldwide public health concern given its significant morbidity and mortality, years of potential life lost, reduced quality of life and elevated healthcare costs. The primary injury occurs at the moment of impact, but secondary injuries might develop as a result of brain hemodynamic abnormalities, hypoxia, and hypotension. The cerebral edema and hemorrhage of the injured tissues causes a decrease in cerebral perfusion pressure (CPP), which leads to higher risk of cerebral ischemia, herniation and death. In this setting, our role as physicians is to minimize damage by the optimization of the CPP and therefore to reduce mortality and improve neurological outcomes. Performing a transcranial doppler ultrasound (TCD) allows to estimate cerebral blood flow velocities and identify states of low flow and high resistance. We propose to include TCD as an initial assessment and further monitoring tool for resuscitation guidance in patients with severe TBI. We present an Ultrasound-Guided Cardio-cerebral Resuscitation (UGCeR) protocol in Patients with Severe TBI.

Carotid flow as a surrogate of the left ventricular stroke volume.

Transthoracic echocardiography (TTE) is a fundamental tool for hemodynamic monitoring in critical patients. It allows evaluating the left ventricle's stroke volume based on the measurement of the velocity-time integral (VTI) of the left ventricle outflow tract (LVOT). However, in the intensive care unit obtaining adequate echocardiographic views may present a challenge. We propose to measure, as a surrogate of the stroke volume, the carotid flow with a novel technique. This is an observational, prospective, and simple blind study, conducted in the intensive care unit of Sanatorio de los Arcos and Hospital Aleman, in Buenos Aires, Argentina. We measured the carotid systodiastolic flow (CSD) VTI and the carotid systolic flow (CS) VTI at the level of the left supraclavicular fossa and we compared it with the LVOT VTI obtained by TTE. We evaluated 43 subjects. Spearman's correlation coefficient between LVOT VTI and CS VTI was 0.81 (95% CI 0.67-0.89) and between LVOT VTI and CSD VTI was 0.89 (95% CI 0.81-0.94). The Bland-Altman method analysis of the 5-chamber apical window LVOT VTI compared to the CSD VTI showed a bias of - 0.2 (95% CI - 0.82 to 0.43), with a concordance interval between - 4.2 (95% CI - 5.2 to - 3.1) and 3.8 cm (95% CI 2.7 to 4.9). The percentage error was 37.9%. Almost 100% of the values fell within the concordance limits, and no trend was observed in bias across the spectrum of mean variables. Although the CSD VTI could not be interchangeable with the LVOT VTI, it could be considered as its surrogate.

The role of different ultrasound modes in hepatic portal venous gas diagnosis, including a novel method using color M-mode.

Hepatic portal venous gas (HPVG) indicates an abnormal gas buildup within the portal venous system, associated with severe medical conditions. Causes include heightened intraluminal pressure, bowel wall disruption, bowel necrosis, and pathogenic bacteria. Previously considered indicative of extensive bowel necrosis requiring surgery, HPVG is now recognized in non-surgical conditions, posing diagnostic challenges. Doppler-coupled sonography, particularly sensitive for HPVG detection, serves as a valuable initial screening tool. This article synthesizes findings from ultrasound methods for assessing portal venous gas reported in the literature and introduces a new approach using Color M-mode ultrasound.

Exploring diaphragmatic response to high-flow nasal cannula in patients with COVID-19 pneumonia using ultrasound: a proof of concept study.

BACKGROUND: Recent studies have highlighted the recognition of diaphragmatic dysfunction as a significant factor contributing to respiratory disturbances in severely ill COVID-19 patients. In the field of noninvasive respiratory support, high-flow nasal cannula (HFNC) has shown effectiveness in relieving diaphragm dysfunction. This study aims to investigate the diaphragmatic response to HFNC in patients with COVID-19 pneumonia by utilizing ultrasound. METHODS: This retrospective study was conducted in a medical-surgical intensive care unit (ICU) at a tertiary care center in Buenos Aires, Argentina (Sanatorio de Los Arcos) over a 16-month period (January 2021-June 2022). The study included patients admitted to the ICU with a diagnosis of COVID-19 pneumonia who were deemed suitable candidates for HFNC therapy by the attending physician. Diaphragm ultrasound was conducted, measuring diaphragmatic excursion (DE) both before and during the utilization of HFNC for these patients. RESULTS: A total of 10 patients were included in the study. A statistically significant decrease in respiratory rate was observed with the use of HFNC (p = 0.02), accompanied by a significant increase in DE (p = 0.04). CONCLUSION: HFNC leads to a reduction in respiratory rate and an increase in DE as observed by ultrasound in patients with COVID-19 pneumonia, indicating promising enhancements in respiratory mechanics. However, further research is required to validate these findings.

Passive leg raising test using the carotid flow velocity-time integral to predict fluid responsiveness.

PURPOSE: The passive leg raising test (PLR) is a noninvasive method widely adopted to assess fluid responsiveness. We propose to explore if changes in the carotid flow assessed by echo-Doppler can predict fluid responsiveness after a PLR. METHODS: We conducted a performance diagnostic study in two intensive care units from Argentina between February and April 2022. We included patients with signs of tissular hypoperfusion that required fluid resuscitation. We labeled the patients as fluid responders when we measured, after a fluid bolus, an increase greater than 15% in the left ventricle outflow tract (LVOT) VTI in an apical 5-chamber view and we compared those results with the carotid flow (CF) velocity-time integral (VTI) from the left supraclavicular region in a semi-recumbent position and during the PLR. RESULTS: Of the 62 eligible patients, 50 patients (80.6%) were included. The area under the ROC curve for a change in CF VTI during the PLR test was 0.869 (95% CI 0.743-0.947). An increase of at least of 11% in the CF VTI with the PLR predicted fluid-responsiveness with a sensitivity of 77.3% (95% CI 54.6-92.2%) and specificity of 78.6% (95% CI 59-91.7%). The positive predictive value was 73.9% (95% CI 57.4-85.6%) and the negative predictive value was 81.5% (95% CI 66.5-90.7%). The positive likelihood ratio was 3.61 and the negative likelihood ratio was 0.29. CONCLUSION: An increase greater than 11% in CF VTI after a PLR may be useful to predict fluid responsiveness among critically ill patients.

Non-invasive diagnosis of diaphragmatic paralysis in botulism using ultrasound.

This case study explores foodborne botulism, a severe illness caused by botulinum neurotoxin-contaminated food. It leads to bilateral descending paralysis, involving the diaphragm. We highlight diaphragmatic ultrasound as a non-invasive diagnostic tool. A 50-year-old obese male developed diplopia and weakness after consuming contaminated food, rapidly progressing to severe symptoms. Mechanical ventilation became necessary due to respiratory failure. Diaphragmatic ultrasound confirmed bilateral diaphragm paralysis despite early antitoxin treatment. The patient experienced complications, requiring tracheostomy and rehabilitation. After five months, he fully recovered diaphragmatic function. This study underscores botulism's life-threatening nature and the vital role of supportive care. Diaphragmatic ultrasound is a safe and effective method for assessing diaphragmatic function in such cases, obviating ionizing radiation exposure. We recommend its routine use for evaluating botulism-induced paralysis.

Tips for carotid ultrasound in the intensive care unit.

The ultrasonography of carotid arteries plays a key role in evaluating cerebrovascular disease. There are some useful considerations to perform it correctly in the intensive care unit, such as using different kind of transducer, Doppler mode optimization, and the correct interpretation of the findings.

A modified subcostal view: a novel method for measuring the LVOT VTI.

PURPOSE: The velocity time integral (VTI) of the left ventricular outflow tract (LVOT) obtained in the apical view by echocardiography can be regarded as a surrogate for the stroke volume. In critically ill patients it is often difficult to obtain an appropriate apical view to assess the VTI. The subcostal view is more accessible, but while it allows a qualitative assessment of the heart, is not adequate for estimating a reliable LVOT VTI, given the inappropriate angle between the Doppler signal and the flow through the LVOT. We present a new modified subcostal view that allows a proper LVOT VTI measurement. METHODS: This is a single-centre experimental, retrospective, and observational study using data from patients in a tertiary-care centre. We included adult patients admitted to the intensive care unit in the period from June 2020 to January 2022, who were evaluated by echocardiography and whose LVOT VTI was measured aligned with the Doppler signal in both the apical five-chamber view and the modified subcostal view. RESULTS: A total of 30 patients were evaluated in the study period by ultrasonography. The Bland-Altman method analysis of the LVOT VTI measured in the apical view compared with that obtained in the subcostal view showed a bias of 0.8 (95% CI 0.39-1.21) with a 95% limit of agreement between - 1.35 (95% CI - 2.06 to - 0.64) and 2.96 (95% CI 2.25-3.67). The percentage error was calculated to be 23%. The Pearson correlation coefficient for the two forms of measurements showed an R value of 0.98 (95% CI 0.96-0.99). CONCLUSION: The LVOT VTI measured in a modified subcostal view is useful for estimating the value of the LVOT VTI obtained in an apical view.

Usefulness of ultrasound in the diagnosis of nosocomial maxillary sinusitis in patients with severe Covid-19 pneumonia: a retrospective study.

PURPOSE: Severe Covid-19 pneumonia frequently presents with infective complications as bacterial and fungal infections, nosocomial maxillary sinusitis is one of them. We describe the role of ultrasonography in the diagnosis of nosocomial maxillary sinusitis in patients undergoing mechanical ventilation due to severe Covid-19 pneumonia. METHODS: Patients with severe pneumonia due to Covid-19 requiring mechanical ventilation and had maxillary sinus occupation by ultrasonography were retrospectively enrolled at intensive care unit of Sanatorio De los Arcos, Buenos Aires, Argentina, between March 2020 and May 2021. RESULTS: We evaluated a total of 171 patients with severe Covid-19 pneumonia requiring mechanical ventilation during the study period. We included 26 patients that had maxillary sinus occupation by ultrasonography (15.2%). Out of the 26 patients, in 17 the diagnosis was confirmed by surgical drainage of the maxillary sinus with positive cultures with a positive predictive value of 85%. In 34.6% of the cases the maxillary sinus disease was unilateral and in 38.4% bilateral. A sinus computed tomography (CT) was performed in 30.7% of the patients. Most of the patients underwent to surgical drainage without a CT scan (66.7%). CONCLUSIONS: Ultrasonography is a useful tool for the detection of maxillary sinus infection in patients with severe Covid-19 pneumonia and avoids to perform a CT scan and, therefore, unnecessary transfers.

Transthoracic echocardiography of patients in prone position ventilation during the COVID-19 pandemic: an observational and retrospective study.

Mechanical ventilation in prone position is a strategy that increases oxygenation and reduces mortality in severe ARDS. The hemodynamic and cardiovascular assessment of these patients is essential. Transthoracic echocardiography (TTE) is a widely used tool to assess hemodynamics in critical care, but the prone position is thought to limit adequate TTE views and goal-oriented measurements. The aim of this study is to show the feasibility of the hemodynamic assessment by transthoracic echocardiography during prone position ventilation (PPV). This is a retrospective, observational study, carried out in the intensive care unit (ICU) of a tertiary-care center in Buenos Aires, Argentina. We included all the adult patients admitted to the ICU between March 2020 and August 2021 who had a TTE examination in PPV due to ARDS. During the study period, we evaluated by TTE a total of 35 patients requiring PPV. The vast majority of the patients had COVID-19 pneumonia (91.4%). In 33 out of 35 (94.3%) cases, it was able to achieve an adequate apical four chamber view. We assessed qualitatively the systolic function of left ventricle (LV) and right ventricle (RV) in all of the successfully evaluated patients. We measured the RV basal diameter (94.3%), RV/LV ratio (77.1%), tricuspid annular plane systolic excursion (TAPSE) (91.4%), and septal mitral annular plane systolic excursion (MAPSE) (88.5%) in most of them. Also, we quantified the left ventricle outflow tract velocity time integral (LVOT VTI) in a large part (68.5%) of the examinations. Transthoracic echocardiography is a useful tool for the hemodynamic assessment of patients in prone position under mechanical ventilation.

Passive leg raising test to predict fluid responsiveness using the right ventricle outflow tract velocity-time integral through a subcostal view.

PURPOSE: The passive leg raising test (PLR) produces a reversible increase in venous return and, if the patient's ventricles are preload dependent, in the cardiac output. As this effect occurs in seconds, the transthoracic echocardiography is optimal for its real time assessment. The utility of the PLR for monitoring fluid responsiveness through the measurement of the left ventricle outflow tract velocity-time integral (LVOT VTI) in an apical 5-chamber view is well stablished. To achieve this view in critically ill patients is often challenging. The aim of this study is to explore the accuracy for predicting fluid responsiveness of the change in the right ventricle outflow tract velocity-time integral (RVOT VTI) from a subcostal view during a PLR. METHODS: This is a diagnostic accuracy study carried out in two centers in Argentina. We included patients admitted to the intensive care unit from January 2022 to April 2022, that required fluid expansion due to signs of tissular hypoperfusion. We measured the RVOT VTI from a subcostal view in a semi-recumbent position and during the PLR, and the LVOT VTI in an apical 5-chamber view before and after a fluid bolus. If the LVOT VTI increased by 15% after the fluid bolus, the patients were considered fluid responders. RESULTS: We included 43 patients. The area under the ROC curve for a change in the RVOT VTI during the PLR was 0.879 (95% CI 0.744-0.959). A change of 15.36% in the RVOT VTI with the PLR predicted fluid responsiveness with a sensitivity of 85.7% (95% CI 57.2%-98.2%) and specificity of 93.1% (95% CI 77.2-99.2). The positive predictive value was 85.7% (95% CI 60.8%-95.9%) and the negative predictive value was 93.1% (95% CI 78.8%-98%). The positive likelihood ratio was 12.43 and the negative predictive value was 0.15. CONCLUSION: The RVOT VTI change during a PLR is suitable for the prediction of fluid responsiveness in critically ill patients.