Evaluation of Acute Appendicitis in Children using Bedside UltrasoundAmanda Bates

Appendicitis

Epidemiology Most common cause of emergent abdominal surgery in

children Rare in very young children More common in males than females Most common in children age 10-20yrs

Classic presentation of anorexia, vomiting, & periumbilical pain migrating to RLQ occurs in only half of all patients

Perforation = surgical emergency

Diagnosing Appendicitis in the ED Clinical diagnosis

HPI – anorexia, periumbilical pain migrating to RLQ, fever, nausea/vomiting

PE – Rovsing sign, Obturator sign, Iliopsoas sign, rebound/guarding, RLQ tenderness

Cannot reliably exclude appendicitis from ddx when classic symptoms are absent

Multiple pediatric clinical scoring systems Alvarado Score Pediatric appendicitis score Refined Low-Risk Appendicitis Score

Diagnosing Appendicitis in the ED Unique challenges with pediatric population

May not be able to communicate clearly/verbalize where pain is located

Symptoms may be nonspecific

Clinical presentation varies by age Children <5yrs: abdominal pain (diffuse vs. RLQ),

diarrhea, fever, N/V, lethargy, irritability Children 5-12yrs: abdominal pain, N/V, limp/R hip pain,

trouble walking, diarrhea, anorexia Children >12yrs: may present similarly to adults

Diagnosing Appendicitis in the ED

Differential for abdominal complaints in children

Infants: necrotizing enterocolitis, volvulus, colic, gastroenteritis, constipation, testicular torsion

Toddlers: intussusception, volvulus, testicular torsion, gastroenteritis, constipation, UTI

Young children: torsion, gastroenteritis, constipation, UTI

Adolescents: torsion, ectopic/intrauterine pregnancy, DKA, IBD, PID, gastroenteritis

Diagnosing Appendicitis in the ED

Can dx with CT or ultrasound

Concern with exposing children to radiation limits use of CT

ACEP guidelines for pediatric population Recommend ultrasound as initial imaging modality Ultrasound can confirm but not exclude appendicitis CT can definitively confirm or exclude appendicitis

Ultrasound Technique

Pain control

High frequency linear array probe

Place on point of maximal tenderness

Graded compression to displace bowel gas

Visualize in longitudinal and transverse planes

Identifying the Appendix

Find ascending colon – no peristalsis, contains gas and fluid – follow to the cecum & identify terminal ileum

Appendix should be at cecal tip ~1cm below ileum

Use psoas muscle and iliac vessels as landmarks

Identifying the Appendix

Normal anatomy

Psoas

Iliac Vessels

Image: http://www.minnisjournals.com.au/ajum/article/Appendicitis-21

Diagnosing Appendicitis

Criteria include: tubular structure, blind ending, noncompressible, >6mm in diameter, nonperistalsing

Transverse view – “target sign”

Doppler can show increased flow to wall of appendix

+/- appendicolith – hyperechoic, cause shadowing

+ sonographic McBurney’s

Limitations in visualizing the appendix: variations in anatomy, perforation, pain, habitus, bowel gas

Acute Appendicitis - Longitudinal

Image: http://www.ultrasoundcases.info/Slide-View.aspx?cat=187&case=6874

Acute Appendicitis - Transverse

Image: http://www.ultrasoundcases.info/Slide-View.aspx?cat=187&case=6874

Acute Appendicitis

Image: http://www.ultrasoundcases.info/Slide-View.aspx?cat=187&case=6874

Evaluation by EM Physicians

Evaluation by EM Physicians Participating pediatric attendings/fellows trained with 30 min lecture

& 30 min of hands on practice

150 scans, 50 cases of verified acute appendicitis Verified by surgical pathology or phone follow up 1 false negative, 5 false positives

Limitations: single center study, convenience sample

EM sonographers demonstrated high specificity in identifying acute appendicitis

Study found reduction in CT use and decreased ED LOS CT rate dec from 44.2% to 27.3% LOS 154 min vs. 288 min for radiology US and 487 min for CT

Evaluation by EM Physicians

Evaluation by EM Physicians

13 peds EM sonographers 1 faculty physician trained 12 fellows (no prior experience scanning

bowel) with 45 min lecture & 5 practice exams

264 scans, 85 cases of verified acute appendicitis Verified by surgical pathology or phone follow up 13 false positive studies

Limitations: single center, lead sonographer performed 43% of study imaging

Ultimately POCUS performed by EM physicians had high specificity, especially in sonographers with more scanning experience

Conclusion

Ultrasound can be used to confirm acute appendicitis in children, a population in which it’s advisable to limit exposure to radiation with CT scans

CT definitive test if US equivocal/appendix not visualized

Bedside ultrasound performed by trained EM physicians can have high specificity comparable to CT or formal US studies

References Clinical Policy: Evaluation and Management of Suspected Appendicitis. American

College of Emergency Physicians. http://www.acep.org/Clinical---Practice-Management/Clinical-Policy--Evaluation-and-Management-of-Suspected-Appendicitis. Accessed October 17, 2015

Appendicitis. Medscape. http://emedicine.medscape.com/article/773895-overview. Accessed October 17, 2015

Wessen DE. Acute Appendicitis in Children. In: UpToDate, Post, TW (Ed), UpToDate, Waltham, MA, 2015

Focus On: Ultrasound for Appendicitis. American College of Emergency Physicians. http://www.acep.org/Continuing-Education-top-banner/Focus-On--Ultrasound-for-Appendicitis. Accessed October 17, 2015

Abdomen and Retroperitoneum. Ultrasound Cases. http://www.ultrasoundcases.info/Slide-View.aspx?cat=187&case=6874. Accessed October 17, 2015

References

Polites SF, Mohamed MI, et al. A simple algorithm reduces computed tomography use in the diagnosis of appendicitis in children. Surgery. 2014; 156:2

Elikashvili I, Tay ET, Tsung JW. The Effect of Point-of-care Ultrasonography of Emergency Department Length of Stay and Computed Tomography Utilization in Children with Suspected Appendicitis. Academic Emergency Medicine. 2014; 163-170

Sivitz AB, Cohen SG, Tejani C. Evaluation of Acute Appendicitis by Pediatric Emergency Physician Sonography. Annals of Emergency Medicine. 2014; 64:4

SonoTutorial: Appendicitis assessment by ultrasound. SonoSpot: Topics in Bedside Ultrasound. https://sonospot.wordpress.com/2014/04/10/sonotutorial-appendicitis-assessment-by-ultrasound-foamed-foamus/.