Thrombotic complications of COVID-19.

INTRODUCTION: The novel coronavirus disease of 2019 (COVID-19) is associated with significant morbidity and mortality. The impact of thrombotic complications has been increasingly recognized as an important component of this disease. OBJECTIVE: This narrative review summarizes the thrombotic complications associated with COVID-19 with an emphasis on information for Emergency Medicine clinicians. DISCUSSION: Thrombotic complications from COVID-19 are believed to be due to a hyperinflammatory response caused by the virus. Several complications have been described in the literature. These include acute limb ischemia, abdominal and thoracic aortic thrombosis, mesenteric ischemia, myocardial infarction, venous thromboembolism, acute cerebrovascular accident, and disseminated intravascular coagulation. CONCLUSION: It is important for Emergency Medicine clinicians to be aware of the thrombotic complications of COVID-19. Knowledge of these components are essential to rapidly recognize and treat to reduce morbidity and mortality in these patients.

Ultrasound for airway management: An evidence-based review for the emergency clinician.

BACKGROUND: Airway management is a common procedure performed in the Emergency Department with significant potential for complications. Many of the traditional physical examination maneuvers have limitations in the assessment and management of difficult airways. Point-of-care ultrasound (POCUS) has been increasingly studied for the evaluation and management of the airway in a variety of settings. OBJECTIVE: This article summarizes the current literature on POCUS for airway assessment, intubation confirmation, endotracheal tube (ETT) depth assessment, and performing cricothyroidotomy with an emphasis on those components most relevant for the Emergency Medicine clinician. DISCUSSION: POCUS can be a useful tool for identifying difficult airways by measuring the distance from the skin to the thyrohyoid membrane, hyoid bone, or epiglottis. It can also predict ETT size better than age-based formulae. POCUS is highly accurate for confirming ETT placement in adult and pediatric patients. The typical approach involves transtracheal visualization but can also include lung sliding and diaphragmatic elevation. ETT depth can be assessed by visualizing the ETT cuff in the trachea, as well as using lung sliding and the lung pulse sign. Finally, POCUS can identify the cricothyroid membrane more quickly and accurately than the landmark-based approach. CONCLUSION: Airway management is a core skill in the Emergency Department. POCUS can be a valuable tool with applications ranging from airway assessment to dynamic cricothyroidotomy. This paper summarizes the key literature on POCUS for airway management.

Impact of endotracheal tube twisting on the diagnostic accuracy of ultrasound for intubation confirmation.

INTRODUCTION: Ultrasound is a readily-available technique used to identify accurate placement of an endotracheal tube (ETT) after an intubation attempt. There is limited research on using manipulation of the ETT to improve the diagnostic accuracy of ETT location confirmation. Our study sought to directly assess whether ETT twisting during the standard grayscale technique influenced the accuracy of intubation confirmation by ultrasound. METHODS: The study was performed using two different fresh cadavers. During each trial, the cadavers were randomized to either tracheal or esophageal intubation. Three blinded, ultrasound fellowship-trained sonographers assessed the location of the ETT post-intubation alternating between using either a technique with no ETT movement or a technique with ETT twisting. In the latter technique, the sonographers manipulated the ETT in using a side-to-side, twisting motion while performing the ultrasound exam. The study measured the accuracy of ETT location identification, time to identification, and sonographer confidence. RESULTS: 540 assessments were performed with equal numbers of tracheal and esophageal intubations. The accuracy of ultrasound using the static technique was 97.8% (95% CI 95.2% to 99.0%) and the accuracy using the ETT twisting technique was 100% (95% CI 98.6% to 100%). The ETT twisting group showed a faster time to identification with a mean time to identification of 4.97 s (95% CI 4.36 to 5.57 s) compared to 6.87 s (95% CI 6.30 to 7.44 s) for the static ETT group. Operator confidence was also higher in the ETT twisting group at 4.84/5.0 (95% CI 4.79 to 4.90) compared to 4.71/5.0 (95% CI 4.63 to 4.78) in the static ETT group. CONCLUSION: There was no statistically significant difference in the accuracy of ETT location identification between the two groups. However, utilizing the ETT twisting technique showed a statistically significant improvement in the time to identification and sonographer confidence.

Current Approach to the Evaluation and Management of Septic Arthritis.

Septic arthritis is an emergent condition caused by bacterial infection of a joint space. The most common etiology is hematogenous spread from bacteremia, but it can also occur from direct inoculation from bites, injection injuries, cellulitis, abscesses, or local trauma. Septic arthritis occurs most frequently in the lower extremities, with the hips and knees serving as the most common locations. The most sensitive findings include pain with motion of the joint, limited range of motion, tenderness of the joint, new joint swelling, and new effusion. Laboratory testing and imaging can support the diagnosis, but the criterion standard is diagnostic arthrocentesis. Treatment involves intravenous antibiotics and joint decompression.

Current Approach to the Evaluation and Management of Hair-Thread Tourniquets.

Hair-thread tourniquet syndrome is a rare, painful condition that occurs when a strand of hair or thread becomes wrapped around toes, fingers, or other appendages. This causes focal edema, which eventually reduces arterial blood flow and can lead to ischemia and necrosis. A thorough physical examination and assessment of risk factors are important. Treatment involves depilatory agents or targeted incision at the bedside or in the operating room. Successfully treated cases can be discharged with local wound care. Parents should be advised on prevention strategies and ensure close follow-up for reexamination.

Accuracy of ultrasound for endotracheal intubation between different transducer types.

INTRODUCTION: Ultrasound has been increasingly utilized for the identification of endotracheal tube (ETT) location after an intubation attempt, particularly among patients in cardiac arrest. However, prior studies have varied with respect to the choice of transducer and no studies have directly compared the accuracy between transducer types. Our study is the first to directly compare the accuracy of ETT confirmation between the linear and curvilinear transducer. METHODS: This study was performed in a cadaver lab using three different cadavers chosen to represent varying neck circumferences. Cadavers were randomized to tracheal or esophageal intubation. Blinded sonographers assessed the location of the ETT using either a linear or curvilinear transducer in an alternating sequence. Accuracy of sonographer identification, time to identification, and operator confidence were assessed. RESULTS: Four hundred and five assessments were performed with 198 (48.9%) tracheal and 207 (51.1%) esophageal intubations. The linear transducer was 98% (95% CI 95.1% to 99.2%) accurate. The curvilinear transducer was 95% (95% CI 91.1% to 97.3%) accurate. The mean time to identification was significantly lower with the linear transducer [7.46 s (95% CI 6.23 to 8.7 s)] as compared with the curvilinear transducer [11.63 s (95% CI 9.05 to 14.2 s)]. The mean operator confidence was significantly higher with the linear transducer [4.84/5.0 (95% CI 4.76 to 4.91)] than with the curvilinear transducer [4.44/5.0 (95% CI 4.3 to 4.57)]. All operators preferred the linear transducer over the curvilinear transducer. CONCLUSION: The diagnostic accuracy of ultrasound for ETT confirmation did not significantly differ between ultrasound transducer types, but the curvilinear transducer was associated with a longer time to confirmation and lower operator confidence. Further studies are needed to determine if the accuracy would change with more novice providers or in specific patient populations.

Point-of-care ultrasound for the diagnosis of shoulder dislocation: A systematic review and meta-analysis.

INTRODUCTION: Shoulder dislocations are a common injury causing patients to present to the emergency department. Point-of-care ultrasound (POCUS) has the potential to reduce time, radiation exposure, and healthcare costs among patients presenting with shoulder dislocations. We performed this systematic review and meta-analysis to determine the diagnostic accuracy of ultrasound compared with plain radiography in the assessment of shoulder dislocations. METHODS: PubMed, Scopus, CINAHL, LILACS, the Cochrane databases, Google Scholar, and bibliographies of selected articles were assessed for all prospective and randomized control trials evaluating the accuracy of POCUS for identifying shoulder dislocation. Data were dual extracted into a predefined worksheet and quality analysis was performed with the QUADAS-2 tool. Data were summarized and a meta-analysis was performed with subgroup analyses by technique. Diagnostic accuracy of identifying associated fractures was assessed as a secondary outcome. RESULTS: Seven studies met our inclusion criteria, comprising 739 assessments with 306 dislocations. Overall, POCUS was 99.1% (95% CI 84.9% to 100%) sensitive and 99.9% (95% CI 88.9% to 100%) specific for the diagnosis of shoulder dislocation with a LR+ of 796.2 (95% CI 8.0 to 79,086.0) and a LR- of 0.01 (95% CI 0 to 0.17). There was no statistically significant difference between techniques. POCUS was also 97.9% (95% CI 10.5% to 100%) sensitive and 99.8% (95% CI 28.0% to 100%) specific for the diagnosis of associated fractures. CONCLUSIONS: POCUS is highly sensitive and specific for the identification of shoulder dislocations and reductions, as well as associated fractures. POCUS may be considered as an alternate diagnostic method for the management of shoulder dislocations.

Point-of-Care Ocular Ultrasound for the Diagnosis of Retinal Detachment: A Systematic Review and Meta-Analysis.

BACKGROUND: Ocular complaints are common presentations to the emergency department (ED). Among these, retinal detachment can cause significant vision loss if not rapidly diagnosed and referred for appropriate treatment. Point-of-care ultrasound has been suggested to identify the diagnosis rapidly when the ocular examination is limited or the ophthalmology service is not readily available. However, prior studies were limited by small sample sizes, resulting in wide ranges of potential accuracy. The primary outcome for this review was to determine the test characteristics of point-of-care ocular ultrasound for the diagnosis of retinal detachment. METHODS: PubMed, CINAHL, Scopus, LILACS, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and bibliographies of selected articles were assessed for all prospective and randomized controlled trials assessing the accuracy of point-of-care ultrasound for identifying retinal detachment. Data were dual extracted into a predefined worksheet and quality analysis was performed using the QUADAS-2 tool. Data were summarized and a meta-analysis was performed with planned subgroup analyses by location and provider specialty. This review was registered with PROSPERO CRD42018097288. There was no funding for this review. RESULTS: Eleven studies (n = 844 patients) were identified. Overall, ultrasound was 94.2% (95% confidence interval [CI] = 78.4% to 98.6%) sensitive and 96.3% (95% CI = 89.2% to 98.8%) specific for the diagnosis of retinal detachment with a positive likelihood ratio of 25.2 (95% CI = 8.1 to 78.0) and a negative likelihood ratio of 0.06 (95% CI = 0.01 to 0.25). Subgroup analysis found that ultrasound was more accurate among ED patients, but was not significantly different when performed by ED or non-ED providers. CONCLUSIONS: Point-of-care ocular ultrasound is sensitive and specific for the diagnosis of retinal detachment. Future studies should determine the ideal training protocol and the influence of color Doppler and contrast-enhanced ultrasound on diagnostic accuracy.

Variation in the accuracy of ultrasound for the detection of intubation by endotracheal tube size.

INTRODUCTION: Rapid and accurate confirmation of endotracheal tube (ETT) placement is a fundamental step in definitive airway management. Multiple techniques with different limitations have been reported. Recent studies have evaluated the accuracy, time to performance, and physician confidence for ultrasound in both cadaveric models and live patients. However, no study to date has measured the effect of ETT size. Our study is the first to measure the accuracy of ultrasound for ETT confirmation based on ETT size. METHODS: This study was performed in a cadaver lab using three different cadavers chosen to represent varying neck circumferences. Cadavers were intubated in a random sequence with respect to both the location of intubation (i.e., tracheal vs esophageal) and sizes of ETT. Three ETT sizes were utilized: 6.0-, 7.0-, and 8.0-mm. Blinded sonographers assessed the location of the ETT using the static technique. Accuracy of sonographer identification, time to identification, and operator confidence were assessed. RESULTS: 453 assessments were performed. Overall, ultrasound was 99.1% (95% CI 97.8% to 99.7%) accurate in identification of correct location of intubation. The mean time to placement was 6.45 s (95% CI 5.62 to 7.28). The mean operator confidence level was 4.72/5.0 (95% CI 4.65 to 4.78). There was no significant difference between ETT sizes with respect to any of the outcomes. CONCLUSION: The diagnostic accuracy of ultrasound for ETT confirmation did not vary with the use of different ETT sizes. Further studies are needed to determine if the accuracy would change with more novice providers or in specific patient populations.

Ultrasound-assisted Lumbar Punctures: A Systematic Review and Meta-Analysis.

BACKGROUND: Lumbar punctures (LPs) are a common procedure in emergency medicine. However, studies have found that failed procedure rates can be as high as 50%. Ultrasound has been suggested to improve success rates by visually identifying the location and trajectory for the LP procedure. This systematic review and meta-analysis was performed to determine whether the use of ultrasound improved the rate of successful LP performance. METHODS: PubMed, CINAHL, Scopus, LILACS, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and bibliographies of selected articles were assessed for all randomized controlled trials comparing the success rates of ultrasound-assisted LP with landmark-based LP. Secondary outcomes included the rate of traumatic LPs, time to procedural success, number of needle passes, and patient pain score. Data were dual extracted into a predefined worksheet, and quality analysis was performed using the Cochrane Risk of Bias tool. Data were summarized and a meta-analysis was performed with subgroup analyses by pediatric versus adult patients and by operator training level. RESULTS: Twelve studies (n = 957 total patients) were identified. Ultrasound-assisted LP was successful in 90.0% of patients and landmark-based LP was successful in 81.4% of patients. The calculated risk difference (RD) was 8.9% (95% confidence interval [CI] = 1.2% to 16.7%) with an odds ratio (OR) of 2.22 (95% CI = 1.03 to 4.77) in favor of the ultrasound-assisted group. There were fewer traumatic LPs in the ultrasound-assisted group (10.7% vs. 26.5%; RD = -16.4%, 95% CI = -27.6% to -5.2%; OR = 0.28, 95% CI = 0.18 to 0.45). Ultrasound-assisted LP was also associated with a shorter time to successful LP (6.87 minutes vs. 7.97 minutes), fewer mean needle passes (2.07 vs. 2.66), and lower patient pain scores (3.75 vs. 6.31). CONCLUSIONS: Ultrasound-assisted LPs were associated with higher success rates, fewer traumatic LPs, shorter time to successful LP, fewer needle passes, and lower patient pain scores. Ultrasound should be considered prior to performing all LPs, especially in patients with difficult anatomy. Further studies are recommended to determine whether this effect is consistent in both adult and pediatric subgroups, as well as the impact of transducer type and body habitus on this technique.

Ultrasonography for the Confirmation of Endotracheal Tube Intubation: A Systematic Review and Meta-Analysis.

STUDY OBJECTIVE: Intubation is routinely performed in the emergency department, and rapid, accurate confirmation is essential to avoid potentially serious adverse outcomes. The number of studies assessing ultrasonography for the verification of endotracheal tube placement has expanded rapidly in recent years. We performed this systematic review and meta-analysis to determine the sensitivity and specificity of transtracheal ultrasonography for the verification of endotracheal tube location. METHODS: PubMed, the Cumulative Index of Nursing and Allied Health, Scopus, Latin American and Caribbean Health Sciences Literature database, the Cochrane databases, and bibliographies of selected articles were assessed for all prospective and randomized controlled trials evaluating the accuracy of transtracheal ultrasonography for identifying endotracheal tube location. Data were dual extracted into a predefined worksheet and quality analysis was performed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Data were summarized and a meta-analysis was performed with subgroup analyses by location, specialty, experience, transducer type, and technique. Time to confirmation was assessed as a secondary outcome. RESULTS: This systematic review identified 17 studies (n=1,595 patients). Overall, transtracheal ultrasonography was 98.7% sensitive (95% confidence interval [CI] 97.8% to 99.2%) and 97.1% specific (95% CI 92.4% to 99.0%), with a positive likelihood ratio of 34.4 (95% CI 12.7 to 93.1) and a negative likelihood ratio of 0.01 (95% CI 0.01 to 0.02). Subgroup analyses did not demonstrate a significant difference by location, provider specialty, provider experience, transducer type, or technique. Mean time to confirmation was 13.0 seconds. CONCLUSION: Transtracheal sonography is rapid to perform, with an acceptable degree of sensitivity and specificity for the confirmation of endotracheal intubation. Ultrasonography is a valuable adjunct and should be considered when quantitative capnography is unavailable or unreliable.

Comparison of Short- vs Long-axis Technique for Ultrasound-guided Peripheral Line Placement: A Systematic Review and Meta-analysis.

Ultrasound-guided peripheral intravenous line (PIV) placement is associated with increased success rates, decreased time to cannulation, and fewer skin punctures than traditional, landmark-based techniques. However, it is unclear which technique is best. This review compares the short-axis (SA) and long-axis (LA) techniques for PIV placement. PubMed, Embase, Scopus, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and bibliographies of selected articles were assessed for prospective trials evaluating the first pass success rate of SA vs LA ultrasound-guided PIV placement. Secondary outcomes included time to placement, number of needle passes, and incidence of posterior wall puncture. Data were double extracted into a predefined worksheet and quality was assessed using the Cochrane Risk of Bias tool. Three studies (n = 198) were identified. SA was successful in 125/128 placements (97.7%) and LA technique was successful in 114/128 placements (89.1%). There was an odds ratio of 5.35 (95% CI: 1.46-19.58) in favor of the SA technique. There was no difference in the mean number of needle passes. Time to insertion varied between studies. The existing literature suggests that the SA technique is associated with greater success than the LA technique. Based upon the data, short-axis may be considered as the first approach for ultrasound-guided PIV placement among providers comfortable with both techniques, though further studies are needed.

Comparison of color flow with standard ultrasound for the detection of endotracheal intubation.

INTRODUCTION: Intubation is a frequently performed procedure in emergency medicine that is associated with significant morbidity and mortality when unrecognized esophageal intubation occurs. However, it may be difficult to visualize the endotracheal tube (ETT) in some patients. This study assessed whether the addition of color Doppler was able to improve the ability to visualize the ETT location. METHODS: This study was performed in a cadaver lab using three different cadavers chosen to represent varying neck circumference. Cadavers were randomized to tracheal or esophageal intubation. Blinded sonographers then assessed the location of the ETT using either grayscale or color Doppler imaging. Accuracy of sonographer identification of ETT location, time to identification, and operator confidence were assessed. RESULTS: One hundred and fifty intubations were performed and each was assessed by both standard and color Doppler techniques. There were 78 tracheal intubations and 72 esophageal intubations. The standard technique was 99.3% (95% CI 96.3 to 99.9%) accurate. The color flow technique was also 99.3% (95% CI 96.3 to 99.9%) accurate. The mean operator time to identification was 3.24s (95% CI 2.97 to 3.51s) in the standard approach and 5.75s (95% CI 5.16 to 6.33s) in the color flow technique. The mean operator confidence was 4.99/5.00 (95% CI 4.98 to 5.00) in the standard approach and 4.94/5.00 (95% CI 4.90 to 4.98) in the color flow technique. CONCLUSION: When added to standard ultrasound imaging, color flow did not improve accuracy or operator confidence for identifying ETT location and resulted in a longer examination time.

Ultrasound-Guided Peripheral Intravenous Line Placement: A Narrative Review of Evidence-based Best Practices.

Peripheral intravenous line placement is a common procedure in emergency medicine. Ultrasound guidance has been demonstrated to improve success rates, as well as decrease complications and pain. This paper provides a narrative review of the literature focusing on best practices and techniques to improve performance with this procedure. We provide an evidence-based discussion of preparation for the procedure, vein and catheter selection, multiple techniques for placement, and line confirmation.