Hypotensive patient with superior vena cava obstruction diagnosed using resuscitative transesophageal echocardiography

BACKGROUND

Superior vena cava syndrome (SVCS) is a malignancy-related emergency. It is caused by obstruction of blood flow in the superior vena cava (SVC) secondary to intraluminal thrombosis, external compression, or direct invasion of tumor.

CASE SUMMARY

A 49-year-old male presented to the emergency department (ED) with acute hypoxemic respiratory failure. He was intubated and treated as pneumonia. Post-intubation, he became hypotensive, requiring fluid resuscitation and inotropic support. Resuscitative transesophageal echocardiography (TEE) showed external compression by a lung mass and an intraluminal thrombus causing SVC obstruction. Computed tomography (CT) angiography was performed, and it confirmed the TEE findings. A provisional diagnosis of lung carcinoma was made, and he underwent endovascular therapy for rapid symptomatic relief.

DISCUSSION

This case report highlights the role of resuscitative TEE in evaluating a hypotensive patient with clinical suspicion of SVCS at the emergency department. TEE performed at the bedside could help to diagnose and demonstrate the pathology causing SVCS in this case. TEE allowed high-quality image acquisition and was able to overcome the limitation of transthoracic echocardiography (TTE). TEE should be considered as an alternative ED imaging modality in the management of SVCS.

LEARNING POINTS

Transesophageal echocardiography (TEE)-guided transvenous pacing (TVP) in emergency department

BACKGROUND

Placement of a temporary pacemaker is a vital skill in the emergency setting in patients that present with life-threatening bradycardia. Transvenous pacing is the definitive method of stabilizing the arrhythmia compared to transcutaneous pacing, as it provides more comfort and better control of heart rate, until the insertion of a permanent pacemaker.

CASE REPORT

In this case report, we describe the steps using TEE to guide the insertion of transvenous pacer at the emergency department. Traditionally, the process of floating a transvenous pacer wire is performed "blindly" using landmarks and a monitoring ECG finding for capture, or under transthoracic echocardiography (TTE) ultrasound guidance. The blind procedure is associated with higher rate of failure and complications. While guidance using TTE is associated with higher success rates and fewer complications, inadequate imaging of the right side of the heart may limit the utility of this imaging modality. The use of transesophageal echocardiography (TEE) by emergency medicine and critical care physicians has gained traction in recent years due to its clear images and lack of interference with procedures being performed on the chest. In this article, we describe a protocol using TEE to guide the insertion of transvenous pacer through a case illustration.

Airway ultrasound to detect subglottic secretion above endotracheal tube cuff

BACKGROUND

Subglottic secretion had been proven as one of the causes of microaspiration and increased risk of ventilator-associated pneumonia (VAP). The role of ultrasound to detect subglottic secretion has not yet been established.

PURPOSE

The purpose of this study is to determine the sensitivity and specificity of upper airway ultrasound (US) in the detection of subglottic secretions as compared to computed tomography (CT) scanning.

MATERIAL AND METHODS

A prospective observational study was carried out in adult trauma patients requiring mechanical ventilation and cervical CT scan. All patients had an endotracheal tube cuff-pressure maintained between 20 and 30 cm H₂O. Airway US was performed at the bedside immediately before the patient was transferred to the CT scan suite. The sensitivity, specificity, and positive/negative predictive values (PPV, NPV) of the upper airway US detection of subglottic secretions were then calculated and compared with CT findings.

RESULTS

Fifty participants were consecutively included. Subglottic secretions were detected in 31 patients using upper airway US. The sensitivity and specificity of upper airway US in detecting subglottic secretion were 96.7% and 90%, respectively (PPV 93.5%, NPV 94.7%). 18 (58%) patients with subglottic secretions developed VAP during their ICU stay (p = 0.01). The area under the receiver operating curve (AUROC) was 0.977 (95% CI 0.936-1.00).

CONCLUSIONS

Upper airway US is a useful tool for detecting subglottic secretions with high sensitivity and specificity.

CLINICAL IMPLICATIONS

This study shows: 1. Upper airway US may aid in detecting subglottic secretions, which are linked to VAP. 2. Detecting subglottic secretions at the bedside aids in determining the best frequency of subglottic aspiration to clean the subglottic trachea. 3. Upper airway US may also aid in detecting the correct ETT position. Trial registration Clinicaltrials.gov.

CLINICALTRIALS

gov identifier NCT04739878 Date of registration 2nd May 2021 URL of trial registry record https://clinicaltrials.gov/ct2/show/NCT04739878 .

Inhaled volatile anesthetic gas for severe bronchospasm in the emergency department

Bronchospasm is caused by reversible constriction of the smooth muscles of the bronchial tree. This causes obstruction of the lower airways, which is commonly seen at the emergency department (ED) in patients with acute exacerbation of asthma or chronic obstructive pulmonary disease. Ventilation may be difficult in mechanically intubated patients with severe bronchospasm due to airflow limitation, air trapping, and high airway resistance. The beneficial effects of volatile inhaled anesthetic gas had been reported due to its bronchodilation properties. In this case series, we would like to share our experience delivering inhaled volatile anesthetic gas via a conserving device for three patients with refractory bronchospasm at the ED. Inhaled anesthetic gas is safe, feasible and should be considered as an alternative rescue therapy for ventilated patients with severe lower airway obstruction.

Helmet CPAP in the emergency department: A narrative review

BACKGROUND

The choice of correct interface for the right patient is crucial for the success of non-invasive ventilation (NIV) therapy. Helmet CPAP is a type of interface used to deliver NIV. Helmet CPAP improves oxygenation by keeping the airway open throughout the breathing cycle with positive end-expiratory pressure (PEEP).

OBJECTIVE

This narrative review describes the technical aspects and clinical indications of helmet continuous positive airway pressure (CPAP). In addition, we explore the advantages and challenges faced using this device at the Emergency Department (ED).

DISCUSSION

Helmet CPAP is tolerable than other NIV interfaces, provides a good seal and has good airway stability. During Covid-19 pandemic, there are evidences it reduced the risk of aerosolization. The potential clinical benefit of helmet CPAP is demonstrated in acute cardiogenic pulmonary oedema (ACPO), Covid-19 pneumonia, immunocompromised patient, acute chest trauma and palliative patient. Compare to conventional oxygen therapy, helmet CPAP had been shown to reduce intubation rate and decrease mortality.

CONCLUSION

Helmet CPAP is one of the potential NIV interface in patients with acute respiratory failure presenting to the emergency department. It is better tolerated for prolonged usage, reduced intubation rate, improved respiratory parameters, and offers protection against aerosolization in infectious diseases.

Worsening cardiac tamponade after pericardiocentesis in a patient with anterior mediastinum mass: a case report

Background

Mediastinal mass is an entity with variable pathology and clinical spectrum. Anterior mediastinal mass can result in severe symptoms due to involvement of surrounding vital structures such as the great vessels, trachea-bronchial tree, and heart. We highlight a case of cardiac tamponade in a patient with an anterior mediastinal mass that was paradoxically worsened after decompressive pericardiocentesis.

Case summary

A 21-year-old male presented to the emergency department (ED) with breathlessness and hypotension. Bedside focused cardiac ultrasound revealed cardiac tamponade which was made worse with an anterior mediastinal mass compressing the right heart chambers. The patient was intubated for respiratory failure, following which an ultrasound-guided pericardiocentesis was performed. Unexpectedly, his hemodynamic status worsened after aspiration of 1000 mL of pericardial fluid. A repeat focused cardiac ultrasound showed reduced pericardial effusion, but worsening of right heart chambers compression by the mediastinal mass. Re-expansion of the pericardium space with 600 mL of normal saline improved the patient’s vital signs, and reduced the right heart compression. Computed tomography was deferred due to the patient’s hemodynamic instability. Despite resuscitation with fluids and initiation of vasopressor, the patient’s condition deteriorated. He succumbed to his illness due to obstructive shock causing multi-organ failure. The autopsy showed a large anterior mediastinal mass, and histopathological examination confirmed the diagnosis of lymphoma.

Discussion

This case demonstrated the therapeutic challenges of managing a shock patient with anterior mediastinal mass, and massive pericardial effusion causing cardiac tamponade.

Emergency physician-performed emergency bronchoscopy in cardiac arrest patient due to acute foreign body airway obstruction

As foreign body airway obstruction (FBAO) can be life-threatening, it has to be promptly diagnosed and treated. We report a case series of three patients presenting to the emergency department with cardiac arrest due to FBAO. In each case, ventilation was difficult due to high airway resistance. As FBAO was suspected, the emergency physician did a prompt flexible bronchoscopy to confirm the diagnosis and retrieve the foreign body. Flexible bronchoscopy is an important diagnostic and therapeutic tool for emergency airway management, and is a relatively safe procedure if performed by a trained personnel. The life-saving benefits of bronchoscopy outweigh the small risks of complications such as bleeding, desaturation and pneumothorax. In the three cases, the removal of the obstructing material led to immediate improvements in oxygenation and ventilation. The patients had return of spontaneous circulation after cardiopulmonary resuscitation and definite airway control.

Randomized clinical trial comparing helmet continuous positive airway pressure (hCPAP) to facemask continuous positive airway pressure (fCPAP) for the treatment of acute respiratory failure in the emergency department

STUDY OBJECTIVE

To determine whether non-invasive ventilation (NIV) delivered by helmet continuous positive airway pressure (hCPAP) is non-inferior to facemask continuous positive airway pressure (fCPAP) in patients with acute respiratory failure in the emergency department (ED).

METHODS

Non-inferiority randomized, clinical trial involving patients presenting with acute respiratory failure conducted in the ED of a local hospital. Participants were randomly allocated to receive either hCPAP or fCPAP as per the trial protocol. The primary endpoint was respiratory rate reduction. Secondary endpoints included discomfort, improvement in Dyspnea and Likert scales, heart rate reduction, arterial blood oxygenation, partial pressure of carbon dioxide (PaCO2), dryness of mucosa and intubation rate.

RESULTS

224 patients were included and randomized (113 patients to hCPAP, 111 to fCPAP). Both techniques reduced respiratory rate (hCPAP: from 33.56 ± 3.07 to 25.43 ± 3.11 bpm and fCPAP: from 33.46 ± 3.35 to 27.01 ± 3.19 bpm), heart rate (hCPAP: from 114.76 ± 15.5 to 96.17 ± 16.50 bpm and fCPAP: from 115.07 ± 14.13 to 101.19 ± 16.92 bpm), and improved dyspnea measured by both the Visual Analogue Scale (hCPAP: from 16.36 ± 12.13 to 83.72 ± 12.91 and fCPAP: from 16.01 ± 11.76 to 76.62 ± 13.91) and the Likert scale. Both CPAP techniques improved arterial oxygenation (PaO₂ from 67.72 ± 8.06 mmHg to 166.38 ± 30.17 mmHg in hCPAP and 68.99 ± 7.68 mmHg to 184.49 ± 36.38 mmHg in fCPAP) and the PaO2:FiO2 (Partial pressure of arterial oxygen: Fraction of inspired oxygen) ratio from 113.6 ± 13.4 to 273.4 ± 49.5 in hCPAP and 115.0 ± 12.9 to 307.7 ± 60.9 in fCPAP. The intubation rate was lower with hCPAP (4.4% for hCPAP versus 18% for fCPAP, absolute difference -13.6%, p = 0.003). Discomfort and dryness of mucosa were also lower with hCPAP.

CONCLUSION

In patients presenting to the ED with acute cardiogenic pulmonary edema or decompensated COPD, hCPAP was non-inferior to fCPAP and resulted in greater comfort levels and lower intubation rate.

Resuscitative transesophageal echocardiography in the diagnosis of post-CABG loculated pericardial clot causing cardiac tamponade

Background

Pericardial effusion is a known complication of post-open cardiac surgery which can progress to life-threatening cardiac tamponade. Classical signs of tamponade such as hypotension and pulsus paradoxus are often absent. Diagnosing acute cardiac tamponade with transthoracic echocardiography (TTE) can be challenging in post-cardiac surgical patients due to distorted anatomy and limited scanning windows by the presence of surgical dressings or scar. Additionally, this patient population is more likely to have a loculated pericardial effusion, or an effusion that is isoechoic in appearance secondary to clotted blood. These findings can be challenging to visualize with traditional TTE. Missed diagnosis of cardiac tamponade due to loculated pericardial clot can result in delayed diagnosis and clinical management.

Case presentation

We report a case series that illustrates the diagnostic challenge and value of resuscitative transesophageal echocardiography (TEE) in the emergency department (ED) for the diagnosis of cardiac tamponade due to posterior loculated pericardial clot in post-surgical coronary artery bypass graft (CABG) patients.

Conclusions

Cardiac tamponade due to loculated posterior pericardial clot post-CABG requires prompt diagnosis and appropriate management to avoid the potential for hemodynamic instability. Transesophageal echocardiography allows a rapid diagnosis, early appropriate referral and an opportunity to institute appropriate therapeutic measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13089-021-00225-7.

Shock due to superior vena cava obstruction detected with point of care ultrasound

Superior Vena Cava (SVC) syndrome is caused by SVC obstruction by external compression or intraluminal thrombus. Patients with the condition can present with upper body swelling, shortness of breath and shock. This case report highlights the use of point-of-care ultrasound (POCUS) to evaluate a patient with SVC syndrome in the emergency department. The test offers many advantages over computed tomography (CT), venography, and magnetic resonance imaging which are limited in hemodynamically unstable patients. A 60-year-old male presented with acute respiratory distress and shock. The POCUS showed the presence of a right lung consolidation and SVC thrombus. CT revealed the presence of a large mediastinal mass causing compression of the SVC with clot seen inside the vessel. The patient was thrombolysed with intravenous streptokinase and his hemodynamics improved. Further investigation confirmed the diagnosis of lymphoma. The SVC can be visualized with transthoracic echocardiography using either the suprasternal, right supraclavicular or right parasternal approach. In this case, the presence of consolidation of the right lung mass provided an acoustic window for the visualization of the SVC using the right parasternal view, thereby allowing for more rapid diagnosis and management.

Pericardial decompression syndrome: A complication of pericardiocentesis

Pericardial Decompression Syndrome (PDS) is an uncommon but life-threatening complication following pericardiocentesis for cardiac tamponade. We report PDS after pericardiocentesis in two patients that presented to the emergency department with cardiac tamponade. In both cases, pericardiocentesis was performed under ultrasound guidance using the left parasternal approach and approximately 1200-1500 mL of pericardial fluid was removed. Immediately after pericardiocentesis, the haemodynamic status of the patients improved. However, 2-3 h post decompression, both patients developed hypotension and pulmonary edema with reduced left ventricular function, suggestive of PDS. PDS is a condition that is described as paradoxical worsening of vital signs after successful decompression of the pericardium in the setting of acute tamponade. Three possible mechanisms explaining PDS are ischaemic, hemodynamic and autonomic processes. If PDS is unrecognized and untreated, it is associated with a high mortality rate secondary to pulmonary edema and cardiogenic shock. If managed urgently, the cardiopulmonary dysfunction in PDS is usually transient and largely reversible with supportive care.

Usage of airway ultrasound as an assessment and prediction tool of a difficult airway management

Airway assessment is important in emergency airway management. A difficult airway can lead to life-threatening complications. A perfect airway assessment tool does not exist and unanticipated difficulty will remain unforeseen. Current bedside clinical predictors of the difficult airway are unreliable but airway ultrasound can be used as an adjunct to predict difficult laryngoscopy. We report a case of a 60-year-old man presenting to the emergency department with shortness of breath, hoarseness of voice and stridor. Airway ultrasound revealed a large laryngeal mass narrowing the upper airway, extending to bilateral vocal cords with heterogenous echogenicity. In view of impending complete upper airway obstruction, acute respiratory distress and airway ultrasound findings, urgent emergency tracheostomy was chosen as definitive airway over endotracheal intubation or surgical cricothyroidotomy. Point of care ultrasound (POCUS) was used to evaluate this patient with severe upper airway obstruction. A laryngeal mass was detected by ultrasound and this pointed towards the presence of a difficult airway. POCUS was a good non-invasive tool used for airway assessment in this uncooperative and unstable patient. Ultrasound predictors of the difficult airway include the inability to visualize the hyoid bone, short hyomental distance ratio, high pretracheal anterior neck thickness and large tongue size. Besides airway assessment, ultrasound can also help to predict endotracheal tube size, confirm intubation and guide emergency airway procedures such as cricothyroidotomy and tracheostomy. Point of care ultrasound of the upper airway can be used in airway assessment to identify distorted airway anatomy, pathological lesions and guide treatment decisions.

Novel role of focused airway ultrasound in early airway assessment of suspected laryngeal trauma

Background

Upper airway injury secondary to blunt neck trauma can lead to upper airway obstruction and potentially cause a life-threatening condition. The most important aspect in the care of laryngeal trauma is to establish a secure airway. Focused airway ultrasound enables recognition of important upper airway structures, offers early opportunity to identify life-threatening upper airway injury, and allows assessment of the extent of injury. This information that can be obtained rapidly at the bedside has the potential to facilitate rapid intervention.

Case presentation

We report a case series that illustrate the diagnostic value of focused airway ultrasound in the diagnosis of laryngeal trauma in patients presenting with blunt neck injury.

Conclusion

Early recognition, appropriate triaging, accurate airway evaluation, and prompt management of such injuries are essential. In this case series, we introduce the potential role of focused airway ultrasound in suspected laryngeal trauma, and the correlation of these exam findings with that of computed tomography (CT) scanning, based on the Schaefer classification of laryngeal injury.

Fat embolism in right internal jugular vein: incidental ultrasound finding during internal jugular vein cannulation

Background

We report a case study of fat embolism seen on ultrasound at right internal jugular vein during central venous cannulation in a patient diagnosed with fat embolism syndrome. This case demonstrates the importance of ultrasound for evaluation of trauma cases with suspicion of fat embolism.

Case presentation

A 23-year-old trauma patient with closed fracture of left femoral shaft and left humerus presented to our emergency department (ED). 11 h after admission to ED, patient became confused, hypoxic and hypotensive. He was then intubated for respiratory failure and mechanically ventilated. Transesophageal ultrasound revealed hyperdynamic heart, dilated right ventricle with no regional wall abnormalities and no major aorta injuries. Whole-body computed tomography was normal. During central venous cannulation of right internal jugular vein (IJV), we found free floating mobile hyperechoic spots, located at the anterior part of the vein. A diagnosis of fat embolism syndrome later was made based on the clinical presentation of long bone fractures and fat globulin in the blood. Despite aggressive fluid resuscitation, patient was a non-responder and needed vasopressor infusion for persistent shock. Blood aspirated during cannulation from the IJV revealed a fat globule. Patient underwent uneventful orthopedic procedures and was discharged well on day 5 of admission.

Conclusions

Point-of-care ultrasound findings of fat embolism in central vein can facilitate and increase the suspicion of fat embolism syndrome.

Electronic supplementary material

The online version of this article (10.1186/s13089-019-0116-9) contains supplementary material, which is available to authorized users.

A feasibility study on bedside upper airway ultrasonography compared to waveform capnography for verifying endotracheal tube location after intubation

Background

In emergency settings, verification of endotracheal tube (ETT) location is important for critically ill patients. Ignorance of oesophageal intubation can be disastrous. Many methods are used for verification of the endotracheal tube location; none are ideal. Quantitative waveform capnography is considered the standard of care for this purpose but is not always available and is expensive. Therefore, this feasibility study is conducted to compare a cheaper alternative, bedside upper airway ultrasonography to waveform capnography, for verification of endotracheal tube location after intubation.

Methods

This was a prospective, single-centre, observational study, conducted at the HRPB, Ipoh. It included patients who were intubated in the emergency department from 28 March 2012 to 17 August 2012. A waiver of consent had been obtained from the Medical Research Ethics Committee. Bedside upper airway ultrasonography was performed after intubation and compared to waveform capnography. Specificity, sensitivity, positive and negative predictive value and likelihood ratio are calculated.

Results

A sample of 107 patients were analysed, and 6 (5.6%) had oesophageal intubations. The overall accuracy of bedside upper airway ultrasonography was 98.1% (95% confidence interval (CI) 93.0% to 100.0%). The kappa value (Κ) was 0.85, indicating a very good agreement between the bedside upper airway ultrasonography and waveform capnography. Thus, bedside upper airway ultrasonography is in concordance with waveform capnography. The sensitivity, specificity, positive predictive value and negative predictive value of bedside upper airway ultrasonography were 98.0% (95% CI 93.0% to 99.8%), 100% (95% CI 54.1% to 100.0%), 100% (95% CI 96.3% to 100.0%) and 75.0% (95% CI 34.9% to 96.8%). The likelihood ratio of a positive test is infinite and the likelihood ratio of a negative test is 0.0198 (95% CI 0.005 to 0.0781). The mean confirmation time by ultrasound is 16.4 s. No adverse effects were recorded.

Conclusions

Our study shows that ultrasonography can replace waveform capnography in confirming ETT placement in centres without capnography. This can reduce incidence of unrecognised oesophageal intubation and prevent morbidity and mortality.

Trial registration

National Medical Research Register NMRR11100810230.