Pediatric Emergency Ultrasound

1. Pediatric Emergency Ultrasound Mary Emborsky, DO Assistant Clinical Professor Division of Emergency Medicine

2. OBJECTIVES • The state of pediatric emergency ultrasound • General approach to pediatric emergency ultrasound • Cases

3. THE STATE OF PEDIATRIC EMERGENCY ULTRASOUND • In the last 20 years, point of care ultrasound (POCUS) has expanded from a screening test in trauma to being used every day by every subspecialty. In Pediatrics it provides: • Minimal exposure to ionizing radiation • Real-time evaluation of the patient and moving organs. • Easier evaluation of children who are less likely to cooperate • Excellent resolution in pediatric patients because of lack of body fat.

4. THE STATE OF PEDIATRIC EMERGENCY ULTRASOUND • There is no standard practice in pediatric emergency ultrasound • In 2016, this process was initiated by Dr. Jen Marin along with several other leaders in PEM POCUS. • Establish standard practice • Delineate training requirements • Recognize areas of further scientific investigation In 2014, PEM POCUS leaders P2NETWORK (P2Network.com)

5. What’s different about pediatric ultrasound? • Children move • They are frightened • They are curious • They might be in pain • It requires patience, smiles and distractions and an appreciation of the pediatric mind and body

6. Suggestions for a good experience • Communicate your intentions to the parent • Communicate your intentions to the child - > 4-5 years. • Careful with word choice ( “we are listening or taking pictures” instead of “we are going to look at your heart”.) • Make the US machine less intimidating. • Let the child hold the probe and feel the gel. • Warm the gel if possible • Lower the machine • Be ready before the probe touches the patient • Careful with turning off the lights. • .

7. Parents can hold or sit with the child if necessary • Use lots of towels to cover and protect clothing • Be aware of exposed body parts • Be prepared to use left and right hands, sit on left or right side of the patient. (you, adapt to them) • Show the child and parents the images • Be efficient • Have a distraction – parents phone, toy, glove…

8. CASE 1 • 2year old male with episodic crying, and more recently vomiting, complaining of abdominal pain. She is less active than usual with decreased appetite. No fevers or diarrhea. • PE – HR 130, BP 100/60, Afebrile, RR 30, Pulse ox 99% • Lying with parent, in no distress, noticeably less active than a typical 2 year old • HEENT wnl, lungs are clear, no crackles or wheezes, • cardiac – mild tachycardia, • abdomen soft, mild fullness on right, cap refill 2 sec

13. Intussuscepient bowel wall Intussuscepient bowel lumen Bowel wall of intussusceptum Mesentary Bowel wall of intussusceptum Lumen of intussusceptum

14. Target or doughnut appearance in transverse view, pseudokidney or hayfork in oblique and longitudinal view Dr. Saikat Pal

15. Small Bowel Intussusception Dr. Mark Kenyon

19. Interloop fluid

20. Indication Evaluate patients with suspected ileocolic intussusception Distinguish between small and large bowel intussusception Evaluation of Advance Disease: • Can be used to determine if blood flow is still present in affected bowel • Identify free fluid surrounding the intussusception or “interloop” fluid • Identify echogenic foci which could represent air within bowel wall

21. Sonographic appearance of intussusception was first reported in 1982 by Bowerman et al. • Verscheldenet al in 1992, large prospective study concluding abdominal US had a sensitivity near 100% (performed by 3rd year radiology residents) for the diagnosis of intussusception. • 88% of intussusceptions were found in the transverse and subhepaticarea • Average thickness of the rim of the doughnut sign was 10mm. • Most ileocolic intussusceptions are about 3cm • Small bowel intussusceptions were much smaller having a cross section diameter of <1cm • US is highly accurate, noninvasive, and does not expose patients to radiation or unnecessary procedures.

22. Research Pediatric Literature: • US has reported sensitivities of 98-100% and specificities of 88-100% • POCUS sensitivity 85% and specificity of 97% Questions still to be answered: • Level of training to become competent • Outcome measures such as time to reduction and length of stay when POCUS used • Define performance characteristics of POCUS assessment of intussusception in different emergency settings.

23. Limitations and pitfalls Ileocolic IS may spontaneously reduce before or after US. Positive identification may not address the presence of a pathological lead point False positives – psoas muscle stool thickened bowel loops Meckels diverticulum Imaging the bowel in only one plane – need to look in transverse and longitudinal

24. CASE 2 10 yo c/o fever for two days, mild congestion and cough. Today c/o right thigh pain and limp. No medications given at home • Exam: Afebrile. HR 90. BP wnl. Wt. 50kg • non-toxic appearing. • HEENT unremarkable. Lung and Heart exam unremarkable. • c/o right leg pain with palpation to thigh but more uncomfortable in general when flex/ext at knee and hip. Mild pain with hip int/ext rotation. Limps when walking. No swelling, rash or warmth noted.

25. Case 2

26. Normal Hip sartorius iliopsoas quadricep

27. Normal Dr. Mary Emborsky

28. Hip Effusion Dr. Mary Emborsky

29. HIP ULTRASOUND • Indications: • Patient presents with hip, thigh or limp and /or suspicion of joint effusion. • Technique • Fluid accumulates anteriorly in the hip joint, elevating the capsule. • Fluid more easily demonstrated with hip in slight flexion and internal rotation. (Legs together and toes up.) • Measure both sides! • Measure from anterior surface of femoral neck to posterior surface of ileospoasmuscle. • Asymmetry between hips of >2mm of fluid in synovial space • >5mm of fluid in synovial space

31. RESEARCH • Case series describing the use of POCUS to evaluate acute onset of limp. • Vieira et al – sensitivity of 80% and specificity 98% detecting hip effusion with POCUS • Vieira et al. • Shavitet al.

32. PITFALLS & PEARLS • Bilateral effusions will not allow for valid contralateral comparisons • Anterior synovial recess measurements vary with position. Use same positioning when measuring both sides. • Patients may have symptomatic effusion that are smaller than established parameters whichcould lead to a false negative exam. • Transducer pressure may obliterate effusions

33. CASE 3 • 2 month old male with h/o vomiting. Seems to be getting worse over the last 2 weeks. Changed formula twice without relief. • Exam unremarkable. Abd soft, you don’t feel an olive.

34. HYPERTROPHIC PYLORIC STENOSIS Ultrasound is the preferred diagnostic modality • Non-invasive technique • Allows direct observation of the pyloric channel morphology and behavior. Indication • Young infants with nonbilious emesis.

35. TECHNIQUE BE PATIENT Using the liver as a sonographic window, the gastric wall is identified overlying a gas and/or fluid-filled stomach. Trace the gastric wall caudally to the right of midline along the lesser curvature of the stomach until it meets the pyloric antrum. OR – find the Gallbladder and look medial to this. The incisura angularismarks the beginning of the pyloric antrum which appears like a notch in the gastric wall’s serosal surface. Measure the width of the muscular layer then AND length of pyloris Look for gastric contents moving through pyloris

36. technique • Warm gel • Perform after feeding infant an ounce of clear fluid • Parent can hold the child • Use a high frequency probe • Transverse position • Start in RUQ, look for gallbladder • May need to try in left lateral decubitus or right lateral decubitus positions

37. Measurements A pyloric muscle thickness of less than 2 mm is considered normal, between 2 and 2.9 mm seen in both normal and pylorospasm, and greater than 3 mm considered diagnostic of HPS. The channel length may be difficult to measure in a normal patient and is less consistent than the more easily appreciated pyloric muscle thickness. The channel length is considered abnormal if it is greater than 15 mm Many people remember 3.14

38. Other Helpful findings “Antral nipple” sign seen in long-axis view where the opposed mucosa layers project back into the antrum “Shoulder” sign, created by the circular pyloric muscle similarly projecting into the antrum “Donut” or “Target” sign seen when the pylorus is viewed in cross section. In addition, there is failure of gastric contents to pass through the pyloric channel when visualized in real time.

39. RESEARCH • A prospective study of PEM fellows and a PEM attending physician found 100 % (95 % CI 62–100 %) sensitivity and 100 % (95 % CI 92–100 %) specificity when evaluating patients with suspected HPS, with measurements of pyloric muscle wall width and length that were not statistically different (p = 0.50 and p = 0.79, respectively) from those of radiology specialists • Sivitz et al.

45. HPS in premature infants • HPS develops at the same age as in term infants, but their smaller size should be taken into consideration. • Argyropoulou and Haiderboth found a correlation with body weight, providing normal values for muscle thickness, canal length and canal width from prematurity to full-term infants.

46. Questions still to be answered The test characteristics of POCUS in the evaluation of the pylorus for HPS require continued evaluation. Variable measurements have been used in radiology texts to establish the diagnosis for HPS. There is currently no definitive consensus regarding absolute measurements.

47. Challenges Difficulty with pyloric visualization may arise from gastric over-distention, which may displace the pylorus posteriorly. Try left lateral decubitus position - this will help move the pylorus into a more anterior position. Gastric air or bowel gas may cause shadowing artifact over the area of interest. Try right lateral decubitus position – this allows fluid to fill in the antrum to act as a window.

48. QUESTIOns?

49. REFERENCES • Costa Dias, Silvia et al. “Hypertrophic pyloric stenosis: tips and tricks for ultrasound diagnosis”. Insights Imaging. 2012. 3:427. • De Bruyn, Rose. Pediatric Ultrasound. Churchill Livingstone Elsevier. 2010. • Doniger, Stephanie. Pediatric Emergeny and Critical Care Ultrasound. Cambridge. 2013. • Marin et al. Pediatric Emergency Medicine point-of-care: summary of the evidence” Critical Ultrasound Journal. 2016. 8:16 • Riera, A et al. “Diagnosis of Intussusception by physician Novice sonographers in the Emergency Department” Annals of Emergency Medicine. 2012. 20:1. • Sanchez, T et al. “Sonography of Abdominal Pain in Children” J Ultrasound Medicine. 2016. 35:627. • Shavit I, Eidelman M, Galbraith R. “Sonography of the hip-joint by the emergency physician: its role in the evaluation of children presenting with acute limp.” PediatrEmerg Care 2006:22:570–573 241. • SivitzA, Tejani C, Cohen S. “Evaluation of hypertrophic pyloric stenosis by pediatric emergency physician sonography”. AcadEmerg Med 2013:20:646–651. • Vieira RL, Levy JA. “Bedside ultrasonography to identify hip effusions in pediatric patients.” Ann Emerg Med 2010:55:284–289.