PLUS

Emergency medicine as a specialty is far ahead of any other in the use of bedside ultrasound.  However, it’s use is spreading.  This article shows that it can be practically implemented in a rural family practice setting.

Can Fam Physician. 2012 Mar;58(3):e172-8.
Office-based ultrasound screening for abdominal aortic aneurysm.
Blois B.
Source
Colchester Regional Hospital, Truro, NS. beau.blois@dal.ca
Abstract
OBJECTIVE:
To assess the efficacy of an office-based, family physician–administered ultrasound examination to screen for abdominal aortic aneurysm (AAA).
DESIGN:
A prospective observational study. Consecutive patients were approached by nonphysician staff.
SETTING:
Rural family physician offices in Grand Forks and Revelstoke, BC.
PARTICIPANTS:
The Canadian Society for Vascular Surgery screening recommendations for AAA were used to help select patients who were at risk of AAA. All men 65 years of age or older were included. Women 65 years of age or older were included if they were current smokers or had diabetes, hypertension, a history of coronary artery disease, or a family history of AAA.
MAIN OUTCOME MEASURES:
A focused “quick screen”, which measured the maximal diameter of the abdominal aorta using point-of-care ultrasound technology, was performed in the office by a resident physician trained in emergency ultrasonography. Each patient was then booked for a criterion standard scan (i.e., a conventional abdominal ultrasound scan performed by a technician and interpreted by a radiologist). The maximal abdominal aortic diameter measured by ultrasound in the office was compared with that measured by the criterion standard method. The time to screen each patient was recorded.
RESULTS:
Forty-five patients were included in data analysis; 62% of participants were men. The mean age was 73 years. The mean pairwise difference between the office-based ultrasound scan and the criterion standard scan was not statistically significant. The mean absolute difference between the 2 scans was 0.20 cm (95% CI 0.15 to 0.25 cm). Correlation between the scans was 0.81. The office-based ultrasound scan had both a sensitivity and a specificity of 100%. The mean time to screen each patient was 212 seconds (95% CI 194 to 230 seconds).
CONCLUSION:
Abdominal aortic aneurysm screening can be safely performed in the office by family physicians who are trained to use point-of- care ultrasound technology. The screening test can be completed within the time constraints of a busy family practice office visit. The benefit of screening for AAA in rural patients might be great if local diagnostic ultrasound service and emergent transport to a vascular surgeon are not available

This is a simple review article concerning the use of FAST in trauma and restates what we already know.  FAST is good but a negative study does NOT rule out significant intraabdominal injury.  It’s great to see bedside ultrasound in a major journal like JAMA.

JAMA. 2012 Apr 11;307(14):1517-27.
Does this adult patient have a blunt intra-abdominal injury?
Nishijima DK, Simel DL, Wisner DH, Holmes JF.
Source
Department of Emergency Medicine, University of California Davis School of Medicine, Sacramento, USA. daniel.nishijima@ucdmc.ucdavis.edu
Abstract
CONTEXT:
Blunt abdominal trauma often presents a substantial diagnostic challenge. Well-informed clinical examination can identify patients who require further diagnostic evaluation for intra-abdominal injuries after blunt abdominal trauma.
OBJECTIVE:
To systematically assess the precision and accuracy of symptoms, signs, laboratory tests, and bedside imaging studies to identify intra-abdominal injuries in patients with blunt abdominal trauma.
DATA SOURCES:
We conducted a structured search of MEDLINE (1950-January 2012) and EMBASE (1980-January 2012) to identify English-language studies examining the identification of intra-abdominal injuries. A separate, structured search was conducted for studies evaluating bedside ultrasonography.
STUDY SELECTION:
We included studies of diagnostic accuracy for intra-abdominal injury that compared at least 1 finding with a reference standard of abdominal computed tomography, diagnostic peritoneal lavage, laparotomy, autopsy, and/or clinical course for intra-abdominal injury. Twelve studies on clinical findings and 22 studies on bedside ultrasonography met inclusion criteria for data extraction.
DATA EXTRACTION:
Critical appraisal and data extraction were independently performed by 2 authors.
DATA SYNTHESIS:
The prevalence of intra-abdominal injury in adult emergency department patients with blunt abdominal trauma among all evidence level 1 and 2 studies was 13% (95% CI, 10%-17%), with 4.7% (95% CI, 2.5%-8.6%) requiring therapeutic surgery or angiographic embolization of injuries. The presence of a seat belt sign (likelihood ratio [LR] range, 5.6-9.9), rebound tenderness (LR, 6.5; 95% CI, 1.8-24), hypotension (LR, 5.2; 95% CI, 3.5-7.5), abdominal distention (LR, 3.8; 95% CI, 1.9-7.6), or guarding (LR, 3.7; 95% CI, 2.3-5.9) suggest an intra-abdominal injury. The absence of abdominal tenderness to palpation does not rule out an intra-abdominal injury (summary LR, 0.61; 95% CI, 0.46-0.80). The presence of intraperitoneal fluid or organ injury on bedside ultrasound assessment is more accurate than any history and physical examination findings (adjusted summary LR, 30; 95% CI, 20-46); conversely, a normal ultrasound result decreases the chance of injury detection (adjusted summary LR, 0.26; 95% CI, 0.19-0.34). Test results increasing the likelihood of intra-abdominal injury include a base deficit less than -6 mEq/L (LR, 18; 95% CI, 11-30), elevated liver transaminases (LR range, 2.5-5.2), hematuria (LR range, 3.7-4.1), anemia (LR range, 2.2-3.3), and abnormal chest radiograph (LR range, 2.5-3.8). Symptoms and signs may be most useful in combination, particularly in identification of patients who do not need further diagnostic workup.
CONCLUSIONS:
Bedside ultrasonography has the highest accuracy of all individual findings, but a normal result does not rule out an intra-abdominal injury. Combinations of clinical findings may be most useful to determine which patients do not require further evaluation, but the ideal combination of variables for identifying patients without intra-abdominal injury requires further study.
PMID: 22496266 [PubMed - indexed for MEDLINE]

Am Surg. 2012 Apr;78(4):468-70.

Qualitative assessment of the inferior vena cava: useful tool for the evaluation of fluid status in critically ill patients.
Ferrada P, Anand RJ, Whelan J, Aboutanos MA, Duane T, Malhotra A, Ivatury R.
Source
Virginia Commonwealth University, Richmond, Virginia, USA.
Abstract
Inferior vena cava (IVC) diameter change on limited transthoracic echocardiogram (LTTE) can provide a useful guide of fluid status evaluation in critically ill patients. Institutional review board approval was obtained. Prospective evaluation of hemodynamic status was performed in hypotensive patients via LTTE. Images were obtained using an ultrasound machine without M-mode capability. Qualitative assessment of the IVC was obtained via subxyphoid window. FLAT IVC was defined as diameter less than 2 cm and FAT IVC when the vein was equal or larger than 2 cm. Collapsibility was assessed by observing respiratory variation of the vessel. Lactate was measured before and after therapy was initiated. A follow-up LTTE was obtained after fluid challenge. A total of 108 LTTE were performed. Patients’ age ranged from 18 to 89 years with an average of 53. Admission diagnosis was blunt trauma in 66 patients, penetrating trauma in 17, whereas 25 had nontraumatic intra-abdominal emergency. Sixty-nine patients were receiving mechanical ventilation at time of LTTE. Seventy-three patients had a FLAT IVC, and received fluid challenge as therapy. All patients had a change in IVC volume from “FLAT” to “FAT” after the fluid challenge. Seventy-one patients (97%) had resolution of hypotension after the first fluid challenge. Two patients had persistent hypotension and received a second fluid challenge. Follow-up LTTE demonstrated a FAT IVC and lack of collapsibility. Lactate decreased in all 73 patients after therapy guided by LTTE (P < 0.00001) Evaluation of the IVC diameter via LTTE offers a rapid, non invasive way to evaluate fluid status in critically ill patients.

Stomach ultrasound?  I am curious if there is utility in using this to evaluate patients who have concern for significant upper GI hemorrhage.

Intensive Care Med. 2011 Apr;37(4):627-31. Epub 2011 Feb 2.

Utility of ultrasonography for detection of gastric fluid during urgent endotracheal intubation.

Koenig SJ, Lakticova V, Mayo PH.

Department of Medicine, Long Island Jewish Medical Center, New Hyde Park, NY, 11040, USA. skoenig@nshs.edu

Abstract

PURPOSE:

Aspiration of gastric contents is a dangerous complication of urgent endotracheal intubation (UEI). Left upper quadrant (LUQ) ultrasonography may have the potential to decrease this complication by identifying patients with gastric fluid content, thereby allowing the UEI team to evacuate gastric contents prior to intubation.

METHODS:

This was an observational study of 80 UEIs where LUQ ultrasonography was performed in a medical intensive care unit of a tertiary care hospital. The subjects were 80 patients requiring UEI. Gastric fluid content was identified as an anechoic or hypoechoic space in the appropriate anatomic position. If potentially consequential fluid was identified, it was evacuated using a gastric tube. Repeat LUQ ultrasonography confirmed removal of gastric contents prior to induction.

RESULTS:

A total of 80 patients had LUQ ultrasonography performed; 19 (24%) had gastric fluid content identified and 13 (16%) had sufficient gastric fluid content such that the UEI team proceeded with gastric tube insertion. Following gastric fluid removal, repeat ultrasonography showed absence of gastric fluid. Gastric fluid volume removed was 553 ± 290 ml (mean ± standard deviation, SD). None of the 80 patients had a clinically consequential aspiration event. Performance of ultrasonography took fewer than 2 min. No patient had complication related to the ultrasonography or removal of gastric contents.

CONCLUSIONS:

Ultrasonography is useful for the detection of gastric fluid. This technique may have utility in reducing risk of a clinically consequential aspiration event during UEI.

IVC assessment is a valuable adjunct in the treatment of acutely ill patients.  This articles shows good inter-observer reliability.

Acad Emerg Med. 2011 Jan;18(1):98-101. doi: 10.1111/j.1553-2712.2010.00952.x.

The interrater reliability of inferior vena cava ultrasound by bedside clinician sonographers in emergency department patients.

Fields JM, Lee PA, Jenq KY, Mark DG, Panebianco NL, Dean AJ.

Department of Emergency Medicine, University of Pennsylvania, Philadelphia, PA, USA.

Abstract

OBJECTIVES:

Inferior vena cava ultrasound (IVC-US) is a noninvasive bedside tool to assess intravascular volume status. This study set out to investigate the interrater reliability of IVC-US by bedside clinician sonographers and determine whether alternative methods of IVC-US such as B-mode and visual estimation are equally reliable to traditional M-mode.

METHODS:

A convenience sample of adult emergency department (ED) patients was prospectively enrolled. Each patient underwent IVC-US by two different emergency physicians (EPs), each of whom first performed visual estimation of IVC percent collapse and of volume status, followed by caliper measurements in M-mode and B-mode. EPs were blinded to patient data and to the other sonographer’s results. For each technique, interrater reliability was determined between the two EPs’ assessments using intraclass correlation coefficients (ICC) for continuous data and Cohen’s weighted kappa for categorical data. In addition, analysis was performed on M-mode diameter measurements to determine the relationship between sonographer and patient characteristics on interrater reliability.

RESULTS:

Five EPs performed 92 US exams on 46 patients. Using M-mode, the ICC for maximum IVC diameter was 0.81 (95% confidence interval [CI]=0.67 to 0.89), and for minimum diameter was 0.77 (95% CI=0.62 to 0.87). There were no statistically significant differences between the caliper methods used for IVC measurements (M-mode diameter, B-mode diameter, or B-mode area). Agreement for visually estimated IVC collapse (0.60, 95% CI=0.36 to 0.76) was similar to agreement for calculated M-mode IVC collapse index (0.52, 95% CI=0.27 to 0.71). Cohen’s weighted kappa for volume status based on visual estimation of IVC filling (size, shape, and collapse) was 0.64 (95% CI=0.53 to 0.73). ICC values for M-mode diameter measurements were significantly higher in studies involving patients who were noneuvolemic and studies in which sonographers had each performed at least five prior IVC-US.

CONCLUSIONS:

Emergency physicians’ US measurements of IVC diameter have a high degree of interrater reliability. IVC percent collapse by visual estimation or based on caliper measurements have lower, but still moderate to good reliability. The use of the visual estimation technique should be considered by clinicians who have learned to obtain measured parameters of IVC filling because it is equally reliable to traditional M-mode and can be performed more rapidly.