SonoStudy: Appendicitis diagnosed by TransVaginal Ultrasound #FOAMed #FOAMus

In a publication in WestJEM by Bramante, Raio and team, they discuss two cases of appendicitis found on trans-vaginal ultrasound. Now, this is something that I have been told can happen, but there are few studies on it. It makes sense. First off, the trans-vaginal probe is high frequency, there is an empty bladder and there is a regional evaluation of the pelvis. The appendix can lie low and be visualized, and diagnosed with acute appendicitis. Raio also published a study on this in Emergency Medicine International. They studied 224 females with right lower quadrant pain suspicious for appendicitis excluding those pregnant or under 16yrs old. They had 27 with a positive ultrasound for gyn pathology and 55 had appendicitis per OR report. Of course they wondered if they should have looked for the appendix too! Other studies have shown that with both a transabdominal and a transvaginal ultrasound, you can improve accuracy in appendicitis diagnoses, but that wasnt necessarily to look for the appendix. The Journal of Ultrasound in Medicine published in 2006 about a case of transvaginal US and appendicitis very nicely too. The OB literature also stated how some of their cases of pelvic pain had appendicitis seen on both transabdominal and transvaginal ultrasound.

Ok, back to the case reports in WestJEM by Bramante et al. The 2 cases showed the evaluation and pretty obvious sonographic images seen with acute appendicitis with transvaginal ultrasound after an equivocal transabdominal ultrasound:

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SonoNews: New Guidelines- reduce risk of premature diagnosis of non-viable pregnancy #FOAMed

In a meeting of 15 members of the radiology, Ob/Gyn, and emergency medicine communities, new criteria were set that was published in NEJM Oct 2013 so that we dont prematurely state that a pregnancy is non-viable. This is pretty important, and a subject that I posted about earlier as well when discussing the usefulness (…or useless ness) of the beta hCG. Can you imagine what was done, and I remember this algorithm – you have a patient with 1st trimester pain or vaginal bleeding, no IUP seen on US, low beta Hcg, and OB was called and the patient was given methotrexate??? Well, there have been cases where those patients actually had a viable IUP that showed up a week later… and then the lawsuit happens….scary stuff. It’s different now where we dont care too much about the beta hCG, or whether there is not an IUP, but whether we see anything around the ovary….and even then, very close follow up and rechecks may be considered. Below is the Eurekalert and the AuntMinnie articles on it too:

Medical experts recommend steps to reduce risk of inadvertent harm to potentially normal pregnancies

New criteria aim to prevent misdiagnoses of nonviable pregnancies

A panel of 15 medical experts from the fields of radiology, obstetrics-gynecology and emergency medicine, convened by the Society of Radiologists in Ultrasound (SRU), has recommended new criteria for use of ultrasonography in determining when a first trimester pregnancy is nonviable (has no chance of progressing and resulting in a live-born baby). These new diagnostic thresholds, published Oct. 10 in the New England Journal of Medicine, would help to avoid the possibility of physicians causing inadvertent harm to a potentially normal pregnancy.

“When a doctor tells a woman that her pregnancy has no chance of proceeding, he or she should be absolutely certain of being correct. Our recommendations are based on the latest medical knowledge with input from a variety of medical specialties. We urge providers to familiarize themselves with these recommendations and factor them into their clinical decision-making,” said Peter M. Doubilet, MD, PhD, of Brigham and Women’s Hospital and Harvard Medical School in Boston, the report’s lead author.

Among the key points made by the expert panel:

  • Until recently, a pregnancy was diagnosed as nonviable if ultrasound showed an embryo measuring at least five millimeters without a heartbeat. The new standards raise that size to seven millimeters
  • The standard for nonviability based on the size of a gestational sac without an embryo should be raised from 16 to 25 millimeters
  • The commonly used “discriminatory level” of the pregnancy blood test is not reliable for excluding a viable pregnancy

The panel also cautioned physicians against taking any action that could damage an intrauterine pregnancy based on a single blood test, if the ultrasound findings are inconclusive and the woman is in stable condition.

Kurt T. Barnhart, MD, MSCE, an obstetrician-gynecologist at the Perelman School of Medicine at the University of Pennsylvania and a member of the SRU Multispecialty Panel, added, “With improvement in ultrasound technology, we are able to detect and visualize pregnancies at a very early age. These guidelines represent a consensus that will balance the use of ultrasound and the time needed to ensure that an early pregnancy is not falsely diagnosed as nonviable. There should be no rush to diagnose a miscarriage; more time and more information will improve accuracy and hopefully eliminate misdiagnosis.”

Michael Blaivas, MD, an emergency medicine physician affiliated with the University of South Carolina and one of the panelists, emphasized that “These are critical guidelines and will help all physicians involved in the care of the emergency patient. They represent an up-to-date and accurate scientific compass for navigating the pathway between opposing forces felt by the emergency physician and his/her consultants who are concerned about the potential morbidity and mortality of an untreated ectopic pregnancy in a patient who may be lost to follow-up, but yet must ensure the safety of an unrecognized early normal pregnancy.”

Aunt Minnie article :

“In addition, the authors emphasized that the commonly used “discrimination level” of the pregnancy blood test is not reliable for excluding a viable pregnancy. They also cautioned physicians against taking any action that could damage an intrauterine pregnancy based on a single blood test, if the ultrasound findings are inconclusive and the woman is in stable condition.

“The guidelines presented here, if promulgated widely to practitioners in the various specialties involved in the diagnosis and management of problems in early pregnancy, would improve patient care and reduce the risk of inadvertent harm to potentially normal pregnancies,” the authors wrote.

Not stringent enough

Research over the past two to three years has shown that previously accepted criteria for ruling out a viable pregnancy are not stringent enough to avoid false-positive results, but it has been difficult both to disseminate this information to practitioners and to implement standardized protocols.

The challenge is that physicians from multiple specialties — including radiology, obstetrics and gynecology, emergency medicine, and family medicine — are involved in the diagnosis and management of early-pregnancy complications, according to the authors.

“As a result, there is a patchwork of conflicting, often outdated published recommendations and guidelines from professional societies,” they wrote.

To address the problem, SRU in October 2012 organized the Multispecialty Consensus Conference on Early First Trimester Diagnosis of Miscarriage and Exclusion of a Viable Intrauterine Pregnancy. At the conference, researchers reviewed the diagnosis of nonviability in early intrauterine pregnancy of uncertain viability and, separately, in early pregnancy of unknown location. They focused mainly on the initial or only ultrasound study performed during the pregnancy.

The conference participants developed the following guidelines for transvaginal ultrasound diagnosis of pregnancy failure in a woman with an intrauterine pregnancy of uncertain viability.

Findings diagnostic of pregnancy failure:

  • Crown-rump length of ≥ 7 mm and no heartbeat
  • Mean sac diameter of ≥ 25 mm and no embryo
  • Absence of embryo with heartbeat ≥ 2 weeks after a scan that showed a gestational sac without a yolk sac
  • Absence of embryo with heartbeat ≥ 11 days after a scan that showed a gestational sac with a yolk sac

Findings suspicious for but not diagnostic of pregnancy failure:

  • Crown-rump length of < 7 mm and no heartbeat
  • Mean sac diameter of 16-24 mm and no embryo
  • Absence of embryo with heartbeat 7-13 days after a scan that showed a gestational sac without a yolk sac
  • Absence of embryo with heartbeat 7-10 days after a scan that showed a gestational sac with a yolk sac
  • Absence of embryo ≥ 6 weeks after last menstrual period
  • Empty amnion (amnion seen adjacent to yolk sac, with no visible embryo)
  • Enlarged yolk sac (> 7 mm)
  • Small gestational sac in relation to the size of the embryo (< 5 mm difference between mean sac diameter and crown-rump length)

Pregnancy of unknown location

The panel also determined diagnostic and management guidelines related to the possibility of a viable intrauterine pregnancy in a woman with a pregnancy of unknown location.

For the finding of no intrauterine fluid collection and normal (or near-normal) adnexa on ultrasonography, the authors provided the following key points:

  • A single measurement of human chorionic gonadotropin (hCG), regardless of its value, does not reliably distinguish between ectopic and intrauterine pregnancy (viable or nonviable).
  • If a single hCG measurement is < 3,000 mIU/mL, presumptive treatment for ectopic pregnancy with the use of methotrexate or other pharmacologic or surgical means should not be undertaken, in order to avoid the risk of interrupting a viable intrauterine pregnancy.
  • If a single hCG measurement is ≥ 3,000 mIU/mL, a viable intrauterine pregnancy is possible but unlikely. The most likely diagnosis is a nonviable intrauterine pregnancy, so it is generally appropriate to obtain at least one follow-up hCG measurement and follow-up ultrasonogram before undertaking treatment for ectopic pregnancy.

If ultrasound had not yet been performed, the researchers offered the following key point: “The hCG levels in women with ectopic pregnancies are highly variable, often < 1,000 mIU/mL, and the hCG level does not predict the likelihood of ectopic pregnancy rupture,” they wrote. “Thus, when the clinical findings are suspicious for ectopic pregnancy, transvaginal ultrasonography is indicated even when the hCG level is low.”

Panel member Dr. Kurt Barnhart, an ob/gyn at Perelman School of Medicine at the University of Pennsylvania, said in a statement that the guidelines represent a consensus that will balance the use of ultrasound and the time needed to ensure that an early pregnancy is not falsely diagnosed as nonviable.

“There should be no rush to diagnose a miscarriage; more time and more information will improve accuracy and hopefully eliminate misdiagnosis,” he said in the statement.

SonoStudy: Echo/Lung Ultrasound in Ambulatory Dyspneic Pts & Prior HF #FOAMus #FOAMed

In the study published in feb 2014 on ambulatory patients and those with prior heart failure, an obvious indirect message is given: do bedside US in ambulatory patients and you will be able to identify disease processes for which your exam or chest Xray may have limited value. Another message is how the heart relates to the presence of B lines on Lung US. This is correlating to another study that compared lung US to BNP value, cliical assessment and echo.

For a quick review of what B lines look like – see below: Using the phased array or curvilinear probe, place the probe over 8 different zones of the chest wall (4 on each side – 2 anterior and 2 lateral) and if you see these bright “rockets” coming down from the pleural line to the end of the screen when you are at 16cm depth, that is a B line. More than 2 B lines in more than 2 zones, bilaterally, from a thin pleural line is consistent with pulmonary edema. Using your cardiac echo to confirm contractility issues helps confirm the findings. To see more of the tutorial, go here.

See the abstract below:

“Lung ultrasound (LUS) represents a novel, noninvasive method in the assessment of extravascular lung water. We investigated the utility of LUS in ambulatory subjects with dyspnea or prior heart failure (HF).

METHODS:

We studied 81 ambulatory subjects with HF history or dyspnea who underwent transthoracic echocardiography (TTE) with LUS of 8 zones. Subjects with heart transplantation or pulmonary conditions known to interfere with LUS were excluded. A reviewer blinded to the clinical data performed echocardiographic measurements and quantified B-lines (reverberation artifacts arising from the pleural line).

RESULTS:

Of 81 subjects, 74 (91%) (median age 66 years, 39% men, median left ventricular ejection fraction [LVEF] 54%, 39% with prior HF) had adequate LUS images of all 8 zones and were included in the analysis. The number of B-lines ranged from 0-12 (median 2). Increased B-lines, analyzed by tertiles, were associated with larger left ventricular (LV) end-diastolic (P = 0.036) and end-systolic diameters (P = 0.026), septal wall thickness (P = 0.009), LV mass index (P = 0.001), left atrial (LA) volume index (P = 0.005), tricuspid regurgitation (TR) velocity (P = 0.005) and estimated pulmonary artery systolic pressure (PASP) (P = 0.003). In a secondary analysis associations between B-lines (not grouped by tertiles) and LV mass index, LA volume index, TR velocity and PASP remained stable after adjustment for age, gender, BMI and HF history.

CONCLUSIONS:

Sonographic B-lines from LUS are related to measures of LV and LA structure and right ventricular pressure in ambulatory patients with dyspnea or prior HF. The added clinical and prognostic utility of this imaging modality in ambulatory patients warrants further investigation.”

SonoStudy: Is Pelvic Ultrasound necessary after negative CT in non-pregnant women? #FOAMed

In the July 2013 issue of Clinical Radiology, the authors from Harvard Medical School review 126 patient charts of non-pregnant women who had a negative abdominal/pelvic CT from 2005- 2010 who then had a pelvic ultrasound for pelvic pain. Despite the obvious question, which is “why did they get a CT and not an ultrasound in the first place?” which will not be discussed, their findings were surprising. Im not sure why, but I guess it goes to show how good multi-detector CT imaging is for these patients now. This raises the question whether a pelvic ultrasound is needed in these patients given the low yield. It would be nice if this was a multi-site study with thousands of patients to increase the power, but the numbers here cannot be ignored. Below is the abstract:

AIM:

To determine the diagnostic value of pelvic ultrasound following negative abdominal/pelvic computed tomography (CT) in women presenting to the emergency room (ER) with abdominal/pelvic pain, and whether ultrasound altered clinical management in the acute-care setting.

MATERIALS AND METHODS:

Between January 2005 to October 2010, 126 consecutive, non-pregnant women with abdominal/pelvic pain underwent pelvic ultrasound within 24 h following negative abdominal/pelvic CT in the ER. Imaging findings/reports for the CT and ultrasound examinations, and clinical data/outcomes were recorded. The time interval between the CT and ultrasound examinations was calculated. Mean length of stay (LOS) was compared to that of age-matched controls who did not have subsequent ultrasound using the t-test.

RESULTS:

Only 3% (four of 126 cases) of the pelvic ultrasound examinations showed positive findings, all of which were endometrial abnormalities. One patient was diagnosed with an endometrial polyp, whereas the others were lost to follow-up. In none of the four cases was the pelvic ultrasound finding relevant to the acute presentation or altered acute care. The average time between CT to ultrasound was 3 h and 4 min. Mean LOS was 22 h and 13 min for the cohort, and 16 h and 8 min for the age-matched controls, although this was not statistically significant (p = 0.29).

CONCLUSION:

Immediate ultrasound re-imaging of the pelvis following negative CT in women with acute abdominal/pelvic pain yields no additional diagnostic information and does not alter acute care.

 

A similar study was done and published in 2011 out of NYU – abstract below:

Abstract

To determine the added value of reimaging the female pelvis with ultrasound (US) immediately following multidetector CT (MDCT) in the emergent setting. CT and US exams of 70 patients who underwent MDCT for evaluation of abdominal/pelvic pain followed by pelvic ultrasound within 48 h were retrospectively reviewed by three readers. Initially, only the CT images were reviewed followed by evaluation of CT images in conjunction with US images. Diagnostic confidence was recorded for each reading and an exact Wilcoxon signed rank test was performed to compare the two. Changes in diagnosis based on combined CT and US readings versus CT readings alone were identified. Confidence intervals (95%) were derived for the percentage of times US reimaging can be expected to lead to a change in diagnosis relative to the diagnosis based on CT interpretation alone. Ultrasound changed the diagnosis for the ovaries/adnexa 8.1% of the time (three reader average); the majority being cases of a suspected CT abnormality found to be normal on US. Ultrasound changed the diagnosis for the uterus 11.9% of the time (three reader average); the majority related to the endometrial canal. The 95% confidence intervals for the ovaries/adnexa and uterus were 5-12.5% and 8-17%, respectively. Ten cases of a normal CT were followed by a normal US with 100% agreement across all three readers. Experienced readers correctly diagnosed ruptured ovarian cysts and tubo-ovarian abscesses (TOA) based on CT alone with 100% agreement. US reimaging after MDCT of the abdomen and pelvis is not helpful: (1) following a normal CT of the pelvic organs or (2) when CT findings are diagnostic and/or characteristic of certain entities such as ruptured cysts and TOA. Reimaging with ultrasound is warranted for (1) less-experienced readers to improve diagnostic confidence or when CT findings are not definitive, (2) further evaluation of suspected endometrial abnormalities. A distinction should be made between the need for immediate vs. follow-up imaging with US after CT.
One reason for reviewing this is that women may feel uncomfortable with this procedure. Recently there was a lawsuit filed stating a transvaginal US felt like “rape” – take care in your technique. I dont know any specifics of the case, but saw the news report and hoping more info comes.

SonoStudy: Bedside ultrasound improves patient satisfaction! @nobleultrasound #FOAMed

In the era of patient satisfaction, report cards, and bonus structure changes all based on patient surveys, in the August 2013 issue of Journal of Emergency Medicine, Drs. Zoe Howard (prior Stanford ultrasound fellow – oh yeah!), Vicki Noble (a guru of bedside US and one of the most fantastic people I know), along with other superstars performed a study that actually tried to keep some variables that would otherwise sway the results, as standard as possible. These include length of stay and chief complaints.

The authors state it best :”Patient satisfaction is becoming increasingly important as a marker of health care quality. As many hospitals grade physician performance and base reimbursement on patient satisfaction scores, clinical interventions that improve these ratings have become increasingly important. In addition to it being a marker of ED service and performance, there is evidence that patient satisfaction is associated with greater medical compliance, willingness to return or recommend the ED to others, and decreased litigation 1234. That decreased length of stay (LOS) improves patient satisfaction is both intuitive and supported by the literature (5). Three previous studies have reported high patient satisfaction with bedside ultrasound. A Swedish study showed that on leaving the ED, patients with acute abdominal pain who underwent EUS had a small but significant increase in satisfaction compared with those who did not (6). Another study showed comparably high overall patient satisfaction for both EP-performed and radiologist-performed ultrasound compared to no EUS (7). Finally, a small study of patients who presented to the ED with threatened miscarriage also showed higher satisfaction when EUS was used in their evaluation. These women also had increased confidence in their physician’s diagnosis (8).”

So, what does this all mean? Do it, and do it more – they like it!

The authors study abstract below:

Abstract

BACKGROUND:

Bedside ultrasound (US) is associated with improved patient satisfaction, perhaps as a consequence of improved time to diagnosis and decreased length of stay (LOS).

OBJECTIVES:

Our study aimed to quantify the association between beside US and patient satisfaction and to assess patient attitudes toward US and perception of their interaction with the clinician performing the examination.

METHODS:

We enrolled a convenience sample of adult patients who received a bedside US. The control group had similar LOS and presenting complaints but did not have a bedside US. Both groups answered survey questions during their emergency department (ED) visit and again by telephone 1 week later. The questionnaire assessed patient perceptions and satisfaction on a 5-point Likert scale.

RESULTS:

Seventy patients were enrolled over 10 months. The intervention group had significantly higher scores on overall ED satisfaction (4.69 vs. 4.23; mean difference 0.46; 95% confidence interval [CI] 0.17-0.75), diagnostic testing (4.54 vs. 4.09; mean difference 0.46; 95% CI 0.16-0.76), and skills/abilities of the emergency physician (4.77 vs. 4.14; mean difference 0.63; 95% CI 0.29-0.96). A trend to higher scores for the intervention group persisted on follow-up survey.

CONCLUSIONS:

Patients who had a bedside US had statistically significant higher satisfaction scores with overall ED care, diagnostic testing, and with their perception of the emergency physician. Bedside US has the potential not only to expedite care and diagnosis, but also to maximize satisfaction scores and improve the patient-physician relationship, which has increasing relevance to health care organizations and hospitals that rely on satisfaction surveys.

SonoStudy: Right subcostal diaphragm view to confirm ETT placement #FOAMed

In the Apr 2013 issue of Int J Crit Illn Inj Science, the authors from Iran attempt to identify the sensitivity, specificity, positive predictive value and accuracy of the right subcostal diaphragm view in the immediately paralyzed and intubated patient to confirm endotracheal intubation (versus esophageal intubation). This study comes from prior studies done suggesting that by visualizing diaphragm movement with ventilation or BVM, you can ascertain that the ET tube was placed in the trachea and not the esophagus. This adds to the growing number of studies that also discusses visualization of the lung sliding sign after intubation to confirm endotracheal intubation, and the ease at which you can identify the tube in the trachea and the esophagus upon trans-jugular notch view and identification of the ring down artifact through the trachea or a tube shadow beyond the esophagus, respectively.

To view a prior post on airway US and ETT placement confirmation, go here. For a fun airway guided talk by Ultrasound Podcast on it all, go here, and here.

So, after you intubate – look over the jugular notch for the ring down artifact through the trachea with the absence of esophageal shadow, then look for lung sliding on both sides of the chest with BVM or ventilation (this can also assess for pneumothorax prior to intubation), then look at the diaphragm for movement with ventilation post intubation. None will show you exactly where the end of the ET tube is, but you’ll know that youre not in the esophagus with good confidence – especially if your capnography isnt accurate due to post- cardiac arrest and your Xray machine/tech is busy or in the bathroom.

The abstract is below:

Aims:

To assess the sensitivity and specificity of right subcostal ultrasound view to confirm correct endotracheal tube intubation (ETT).

Materials and Methods:

In this prospective study, apneic or paralyzed patients who had an indication of intubation were selected. Intubation and ventilation with bag were performed by the skilled third-year emergency medicine residents. The residents, following a brief training course of ultrasonography, interpreted the diaphragm motion, and identified either esophageal or tracheal intubation. The confirmation of ETT placement was done by the sonographer. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for tracheal versus esophageal intubation.

Results:

A total of 57 patients aged 59 ± 5 who underwent ETT insertion were studied. Thirty-four of them were male (60%). Ultrasound correctly identified 11 out of 12 esophageal intubations for a sensitivity of 92% (95% CI = 62-100), but misidentified one esophageal intubation as tracheal. Sonographers correctly identified 43 out of 45 (96%) tracheal intubations for a specificity of 96% (95% CI = 85-99), but misdiagnosed two tracheal intubations as esophageal.

Conclusions:

This study suggests that diaphragm motion in right subcostal ultrasound view is an effective adjunct to diagnose ETT place in patients undergoing intubation in emergency department.

Likely the best description from the article is below:”…Studies have shown that ultrasound can diagnose paralyzed diaphragm.[16,17] Therefore, it seems practical to detect diaphragm motion during the positive-pressure ventilation by using ultrasound imaging of it. Hsieh, et al. studied the use of diaphragm motion for confirmation of ETT correct placement on 59 children in prenatal intensive care unit (PICU) setting. They diagnosed all intubations correctly with ultrasound imaging with sensitivity and specificity of 100%; however, they had only two esophageal intubations.[25] Kerrey, et al.[26] used diaphragm motion view of ultrasound in confirmation of correct ETT placement in 66 children in PICU. They evaluated the diagnosis of right main bronchus intubation. In their study, the sensitivity and specificity were 88% and 64%, respectively. Although sensitivity and specificity of the ultrasound in our study were high, we cannot strongly state that the ultrasound is a sensitive and specific method, because the confidence interval for sensitivity and specificity were rather wide. Studies have identified the intubation of the right main bronchus using diaphragm motion or observation of the lung sliding sign by placing the probe in the left side of the chest; however, left side of the chest is not as good as the right side for seeing the diaphragm motion.[22,26] If the patient is paralyzed or apneic, it would be suitable to evaluate the diaphragm motion in the right side of the chest to diagnose the esophageal intubation.”

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SonoStudy: Ultrasound of heart and lungs identify preeclamptic pregnant patients at risk

In anesthesiology literature (not yet on pubmed), heart and lung ultrasound has entered the mix to identify pregnant patients at risk for respiratory failure – looking for hypocontractile heart and B lines! Oh yeah! It has received a lot of press, see here, here and here :

“Chicago — (March 18, 2014)

An ultrasound of the lungs could help doctors quickly determine if a pregnant woman with preeclampsia is at risk for respiratory failure, suggests preliminary research published in the April issue of Anesthesiology.

About 60,000 women worldwide die as a result of preeclampsia, which causes severely high blood pressure. Potential complications include stroke, bleeding and excess fluid in the lungs – called pulmonary edema – which can lead to respiratory failure.  The study suggests a lung ultrasound can help doctors easily learn whether a woman with preeclampsia is suffering from pulmonary edema and ensure she receives the correct treatment.

“Lung Ultrasound is fast, safe, noninvasive and easy to use,” said Marc Leone, M.D., Ph.D., lead author of the study and vice chair of the department of anesthesiology and critical care medicine, Hopital Nord, Marseille, France. “We found it allowed us to quickly assess whether a woman with preeclampsia had pulmonary edema and confirm the severity of the condition.”

Doctors often measure urine output to determine if a woman needs fluid administration, but the results are wrong about half of the time. “Lung ultrasound enables the medical team to identify which women really need the fluid treatment,” noted Dr. Zieleskiewicz, the study’s  first author.

Pulmonary edema is typically caused by heart failure, but also can be caused by lung inflammation. Researchers analyzed the use of lung ultrasounds, which can assess lung  edema, are easier to use than cardiac ultrasound and can be performed with devices commonly found in maternity wards. Lung ultrasound highlights white lines mimicking comet tails, irradiating from the border of the lungs. These lines are the reflection of water in the lungs.  The detection of three or more lines strongly suggests the diagnosis of pulmonary edema.

Researchers performed both cardiac and lung ultrasounds before and after delivery in 20 women with severe preeclampsia.  Five of the 20 women (25 percent) had pulmonary edema prior to delivery according to lung ultrasound, while four (20 percent) had the condition according to the cardiac ultrasound. The lung ultrasound identified a patient with non-cardiac pulmonary edema, which the cardiac ultrasound did not detect.

The test results could help ensure that pregnant women with pulmonary edema not be given intravenous or excess fluids, which worsens the condition and can lead to respiratory failure.  Typically, women with pulmonary edema are treated with oxygen and medication to lower the blood pressure or rid the body of excess fluid.  In real time, lung ultrasound also serves to observe improvement or worsening of pulmonary edema.”

SonoCase: Thoracic aortic aneurysms – and a review of the literature #FOAMed

Thoracic aortic aneurysms are much less common than abdominal aortic aneurysms. And, to top it off, the measurements of the thoracic aorta are different than the abdominal aorta, especially in the ascending thoracic aorta. It’s good to know how to look at the thoracic aorta when you need to, and what the normal measurements are so that you can make that immediate decision when a thoracic aneurysm (or dissection) is detected.

Drs. Daignault, Saul, and Lewiss published 2 great case reports in the Journal of EM Aug 2013 issue (subscription needed) on thoracic aortic aneurysms. One patient was a 60 year old male who had blunt trauma to his back by a heavy piece of plaster while at work. He had a BP of 140/80 mm Hg and HR of 90 beats/min. The FAST was negative for free fluid but the aortic root was found to be 5.49cm. This caused them to order a CT angio confirming their findings.  Another patient was an 82 year old male with 1 month of chest pain radiating to his back with history of aortic valve repair and HTN on coumadin. BP was 210/90 mm Hg. A bedside echo was performed and showed descending thoracic aorta aneurysm measuring 4.82cm.  This had a CT Angio done confirming descending thoracic aneurysm.  The abstract is found here, and a prior post on these case reports can be found here.

These cases bring up an excellent reason to review the thoracic aorta. The best cardiac echo view to see visualize the thoracic aorta, if you could only pick one, would be the parasternal long view.

According to a german study where they looked at the thoracic aorta throughout life from 17 to 89 yrs of age  via helical CT with the following methods and results: “Methods: Seventy adults, 17 to 89 years old, without any signs of cardiovascular disease were investigated with helical computed tomography. Aortic diameters were measured at seven predefined thoracic levels. Results: Aortic diameters (mean ± SD) were 2.98 ± 0.46 cm at the aortic valve sinus, 3.09 ± 0.41 cm at the ascending aorta, 2.94 ± 0.42 cm proximal to the innominate artery, 2.77 ± 0.37 cm at the proximal transverse arch, 2.61 ± 0.41 cm at the distal transverse arch, 2.47 ± 0.40 cm at the isthmus, and 2.43 ± 0.35 cm at the diaphragm. Men had slightly longer diameters than did women. All diameters increased with age. There was no influence of weight, height, or body surface area.”

More recently, Medscape authors state that the thoracic aorta dimensions are larger than the abdominal aorta dimensions and that aneursymal definition occurs when it is greater than 50% of the normal size.

Another study in the radiology literature with many more subjects more recently, had the following methods and results: “Methods: 1442 consecutive subjects who were referred for evaluation of possible coronary artery disease underwent coronary CT angiography (CTA) and coronary artery calcium scanning (CACS) (55+11 years, 65% male) without known coronary heart disease, hypertension, chronic pulmonary and renal disease, diabetes and severe aortic calcification. The ascending aortic diameter, descending aortic diameter (DAOD), pulmonary artery (PAD) and chest anterioposterior diameter (CAPD), posterior border of sternal bone to anterior border of spine, were measured at the slice level of mid right pulmonary artery by using end systolic trigger image. The volume of four chambers, ejection fraction of left ventricle, and cardiac output were measured in 56% of the patients. Patients demographic information, age, gender, weight, height and body surface area (BSA), were recorded. The mean value and age specific and gender adjusted upper normal limits (mean + 2 standard deviations) were calculated. The linear correlation analysis was done between AAOD and all parameters. The reproducibility, wall thickness and difference between end systole and diastole were calculated. Result: AAOD has significant linear association with age, gender, descending aortic diameter and pulmonary artery diameter (P<0.05). There is no significant correlation between AAOD and body surface area, four chamber volume, LVEF, CO and CAPD. The mean Intra-luminal AAOD was 31.1 ± 3.9mm and 33.6 ± 4.1 mm in females and males respectively. The upper normal limits (mean + 2 standard deviations) of Intra-luminal AAOD, mean+ standard deviation, was 35.6, 38.3 and 40 mm for females and 37.8, 40.5 and 42.6 mm for males in age group 20 to 40, 41 to 60, above 60 year respectively. Intra-luminal should parallel echocardiography and invasive angiography. Traditional cross sectional imaging (with computed tomography and magnetic resonance imaging) includes the vessel wall. The mean total AAOD was 33.5mm and 36.0 mm in females and males respectively. The upper normal limits (mean + 2 standard deviations) of Intra-luminal AAOD, mean+ standard deviation, was 38.0, 40.7 and 42.4 mm for females and 40.2, 42.9 and 45.0 mm for males in age group 20 to 40, 41 to 60, above 60 year respectively. The inter and intra observer, scanner and repeated measurement variability was low (R value >0.91, P<0.001, coefficient variation <3.2%). AAOD was 1.7 mm less in end-diastole than end systole(P<0.001).” Below is their table illustrating the various measurements by others:

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As Dr Lewiss and colleagues state in their case reports, “The most recent consensus statement by the American Society of Echocardiography (ASE) and the American College of Emergency Physicians (ACEP) recognized that the thoracic aortic pathology can be identified on EP-performed focused cardiac ultrasound (3). Transthoracic echocardiography was shown to be consistent with TEE for measurement of the ascending aorta (21). Taylor et al. demonstrated that EP-performed focused cardiac ultrasound was consistent with CTA measurements for maximal thoracic aortic diameter (2). In these cases, an EP with considerable experience in ultrasound performed these studies, but many EP are trained in the use of focused ultrasound for evaluation of the abdominal aorta. Principals used in this application, such as avoiding measurements in oblique planes, measuring from outer wall to outer wall (for the descending thoracic aorta), and the use of Doppler also may be utilized in the evaluation of the thoracic portion of the aorta.”

SonoCase: 46yo c/o abdominal pain h/o cocaine use – sup mesenteric art dissection #FOAMed

Drs. Davis and Kendall write up a very interesting case in the Aug 2013 issue of Journal of EM where the ultrasound made the diagnosis, quite easily too. They discuss a 46 year old male with a history of current cocaine use AND a prior history of an aortic dissection, of course, who was complaining of sudden onset of abdominal pain and found to be severely hypertensive. The diagnosis on the top of their list was aortic dissection/aneurysm/rupture – and when they looked, they saw even more. Below is the abstract:

Background

A timely diagnosis of aortic dissection is associated with lower mortality. The use of emergent bedside ultrasound has been described to diagnose aortic dissection. However, there is limited literature regarding the use of bedside ultrasound to identify superior mesenteric artery dissection, a known high-risk feature of aortic dissection.

Objective

Our aim was to present a case of superior mesenteric artery dissection identified by bedside ultrasound and review the utility of bedside ultrasound in the diagnosis of aortic emergencies.

Case Report

We report a case of superior mesenteric artery dissection found on emergent bedside ultrasound in a 46-year-old male complaining of abdominal pain with a history of cocaine abuse and prior aortic dissection. Bedside ultrasound in the emergency department revealed an intimal flap in the descending aorta with extension into the superior mesenteric artery prompting early surgical consultation before computed tomography because of concern for acute mesenteric ischemia.

Conclusion

Superior mesenteric artery dissection is a high-risk feature of aortic dissection and can be identified with emergent bedside ultrasound.

Just one of their images is displayed below – but take a look at the video in JEM to truly see the awesomeness. A subscription and password is required, but it’s a great journal with lots of cool ultrasound cases published almost every month.

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SonoOpinion: Does absence of cardiac activity predict resuscitation failure? #FOAMed

In a post in Annals of Emergency Medicine, Dr. Brian Cohn from Washington School of Medicine gave his opinion and reviewed a few articles on cardiac activity and its relation to return of spontaneous circulation.

Does the Absence of Cardiac Activity on Ultrasonography Predict Failed Resuscitation in Cardiac Arrest?

Take-Home Message:

The absence of cardiac activity on ultrasonography does not universally lead to failure of resuscitation in cardiac arrest.

So, it doesnt surprise me, but I would ask this question though: How many with no cardiac activity on bedside ultrasound (no wall motion and no valvular activity) have survived to hospital discharge?  none. I have posted on this before, so you know my opinion already, which is: continue for organ donation purposes, otherwise no resources are needed to be used due to no survival potential. I know, it’s tough to think (and do) that.

Methods

Data Sources

MEDLINE, EMBASE, CINAHL, and the Cochrane Library were searched on February 23, 2011, and again on January 29, 2012. The references of relevant articles were searched for any additional studies. Expert contact, a screening of gray literature, and a review of conference proceedings were also conducted.

Study Selection

Studies in which a clinician performed bedside transthoracic cardiac ultrasonography in adult patients receiving cardiopulmonary resuscitation, and in which the outcome was reported, were selected for further review. Two reviewers assessed the selected articles for inclusion, with disagreement settled by consensus.

Data Extraction and Synthesis

Studies were critically appraised with 8 of the original 14 criteria of the Quality Assessment Tool for Diagnostic Accuracy Studies (QUADAS)1 that were believed to be relevant to the selected studies.

Results

Of 2,539 articles screened, 12 were selected for full review. Four of these did not meet inclusion criteria. The 8 articles in the final analysis included 568 patients, of whom 378 had no cardiac activity present on ultrasonography. The random-effects pooled results for sensitivity and specificity of bedside cardiac ultrasonography as a predictor of return of spontaneous circulation were 92% (95% confidence interval [CI] 85% to 96%) and 80% (95% CI 76% to 84%), respectively. The positive likelihood ratio was 4.3 (95% CI 2.6 to 6.9) and the negative likelihood ratio was 0.2 (95% CI 0.1 to 0.3). Of 378 patients without cardiac activity present, 9 (2.4%; 95% CI 1.3% to 4.5%) achieved return of spontaneous circulation (ROSC) (Table).

Pooled outcomes from the 8 included trials.
ROSC No ROSC
Cardiac activity observed on ultrasonography 98 92
No cardiac activity observed on ultrasonography 9 369

Commentary

Given the low likelihood of survival in cardiac arrest patients presenting to the emergency department without a pulse, as low as 0.9% in one large database,2 efforts have been made to identify predictors of futility in ongoing resuscitation, including cardiac standstill on ultrasonography. In one survey of graduates from the LA County/USC Medical Center residency program, 68% reported using ultrasonography during cardiac arrest, and 91% of these reported using the results in deciding when to terminate resuscitation efforts.3

This systematic review yielded a survival to admission rate of 2.4% in patients with cardiac standstill. Although these results seem to indicate that resuscitation in such patients is not futile, longer-term outcomes should be considered. In previous resuscitation research, survival to hospital admission has proven to be a poor surrogate for survival to hospital discharge or neurologic outcomes.4 The Research Working Group of the American Heart Association Emergency Cardiovascular Care Committee has recommended evaluating survival at 90 days coupled with neurologic assessment by modified Rankin Scale or Cerebral Performance Categories score.5 The current evidence does not support using ultrasonography alone to predict outcomes in cardiac arrest patients.

References

    1. Whiting PF , Weswood ME , Rutjes AW , et al.  Evaluation of QUADAS, a tool for the quality assessment of diagnostic accuracy studies . BMC Med Res Methodol . 2006;6:e9

    1. McNally B , Robb R , Mehta M , et al. Centers for Disease Control and Prevention   Out-of-hospital cardiac arrest surveillance—Cardiac Arrest Registry to Enhance Survival (CARES), United States, October 1, 2005-December 31, 2010 . MMWR Surveill Summ . 2011;60:1–19

    1. Shoenberger JM , Massopust K , Henderson SO . The use of bedside ultrasound in cardiac arrest . Cal J Emerg Med . 2007;8:47–50

    1. Gueugniaud PY , Mols P , Goldstein P , et al.  A comparison of repeated high doses and repeated standard doses of epinephrine for cardiac arrest outside the hospital (European Epinephrine Study Group) . N Engl J Med . 1998;339:1595–1601

  1. Becker LB , Aufderheide TP , Geocadin RG , et al. American Heart Association Emergency Cardiovascular Care Committee; Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation   Primary outcomes for resuscitation science studies: a consensus statement from the American Heart Association . Circulation . 2011;124:2158–2177