Pediatric Lung Ultrasound (PLUS) In Diagnosis of Community Acquired Pneumonia (CAP)

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1 Pediatric Lung Ultrasound (PLUS) In Diagnosis of Community Acquired Pneumonia (CAP) Dr Neetu Talwar Senior Consultant, Pediatric Pulmonology Fortis Memorial Research Institute, Gurugram

2 Study To compare the accuracy of PLUS with CXR in hospitalized, pediatric patients of community acquired pneumonia (CAP)

3 Background

4 CAP Leading cause of morbidity & mortality worldwide Key to Success in Management Focus is upon early detection & Rx

5 Why PLUS? Pediatric Lung Ultrasound (PLUS) recently evolved from conventional role in diagnosing pulmonary edema & fluid status in PICU to a revolutionary role of imaging pulmonary parenchyma, both in & out of ICU

6 What about CXR? Chest Radiography (CXR) facilitates in diagnosis of, both pneumonia as well as related complications

7 However CXR has limitations.. o Ionizing radiation Especially - multiple CXRs Increased risk of cancer o High degree of intra-& interobserver variations o Hence Overestimation Increased use of unnecessary antibiotics o Lack of findings does not r/o diagnosis, esp when strong clinical suspicion

8 Limitations o Time delay ordered & when actually done o Transport o Expensive o May miss the diagnosis: Retro cardiac lesions Juxta diaphragmatic Early stage Lesions < 1 cm o False positive

9 What about CT Chest? Considered as gold standard tool in lung imaging, but.. Greater Limitations: o Higher exposure to ionizing radiation o Limited availability o Cost issues o Difficult patient cooperation, hence need for anesthesia or sedation o Lack of portability o Time Delay

10 Again Why PLUS? Several Advantages o No Radiation o Simple o Reliable o Available as point of care ultrasound (POCUS) o Accurate o Clinician based o Learning curve is faster o Lesser cost o Saves time / Quick to perform Advantage of being available at Bedside

11 Yes, PLUS! o Portable o Diagnostic in: Specific areas which may be missed by CXR (radio occult conditions) Sub cm lesions o Repeatable, FU easy o Reduces need for repeat CXR o Immediate report o Hence. Improved care o More use in resource - limited set up

12 Materials and Methods Study Area Study Type Study Population Dept of Pediatrics, Fortis Memorial Research Institute (FMRI), Gurugram Prospective observational study:1 yr All hospitalized, clinically suspected cases of CAP [as per British Thoracic Society (BTS) guidelines]; age of 3 mths to 18 yrs; meeting inclusion criteria

13 o Informed Written Consent o Ethics Clearance taken o No conflict of interest o No Funding

14 Sample Size o Accuracy of point of care lung ultrasound found in other similar articles was found to range between 60-90%. o Therefore, assuming (p)=80% as accuracy with 10% margin of error, minimum required sample size at 5% level of significance was 62 pts o Our Sample size was 100 (n)

15 Inclusion Criteria o Clinical suspicion of CAP as per BTS o Age: 3 mths to 18 yrs o Willing to participate o Mild / uncomplicated clinical course o Imaging &PLUS within 6 hrs of each other & within 24 hrs of hospitalization

16 Exclusion Criteria o Age:< 3 mths or > 18 yrs o K/C/O congenital lung disease o Known C/O chronic / complex condition o Chronic Resp condition o Known C/O malignancy o Hemodynamically unstable o CXR done from outside or not within 6 hrs of PLUS o Mechanical ventilation o Congenital heart disease o Immunocompromised pt o Bronchial Asthma

17 Phillips IU22 Clips / Images Recorded

18 Lung Ultrasound o Simple & portable ultrasound machine o Curvilinear (3.5-5 megahertz) & linear probes (high resolution; megahertz) Each hemi thorax divided: 1 Anterior superior 2 Anterior inferior 3 Lateral superior 4 Lateral inferior 5 Posterior superior 6 Posterior inferior

19 Zones

20 Lung Ultrasound Definitions Consolidation Nonaerated lung Lobar Consolidation - lobe or a segment affected Peripheral Consolidation - focal area of nonaerated lung, typically abutting pleural surface

21 Air bronchogram Punctate or branching echogenicities within areas of lung consolidation Static No motion within bronchi Dynamic - move within the bronchi Mass o Focal solid lesion o Doesn t appear to be arising from lung parenchyma Doppler o +/- of color Doppler flow within an area of consolidation or mass

22 (N) Lung o Pleural Line o Sliding Sign o A Lines o Seashore Sign M Mode

23 Longitudinal Scan o Pleural line - regular echogenic line - moves continuously during respiration o Lung Sliding Sign - Pleural motion

24 Transverse Scan A lines o Pleura-lung interface o Parallel curvilinear o Regular intervals from pleura o Normal aeration pattern

25 M-mode cursor over pleural line; 2 patterns: o Motionless portion of chest above pleural line - horizontal waves, o Sliding below pleural line - granular pattern, sand Seashore Sign

26 o Absence of A lines o Hypoechogenic area; poorly defined borders o Compact underlying comet tail artifacts B o Air Bronchograms o Fluid bronchograms o Hepatization of lung o Shred Sign Pneumonia

27 B Lines o Vertical comet-tail Artifacts - pleural line o Erase A lines o Move with lung sliding o Presence is due to fluidrich subpleural interlobular septae, surrounded by air

28 Hepatization Air content further decreases (lung consolidations), acoustic window becomes completely open, & lung - directly visualized like solid parenchyma (liver/ spleen)

29 Air bronchograms

30 Shred Sign Deeper border of consolidated lung tissue that makes contact with aerated lung tissue is irregular & shredded

31 INTERPRETATION CODE-SHEET OF LUNG ULTRASOUND LUNG ULTRASOUND REPORT FORM PATIENT IDENTIFICATION NUMBER: DATE OF ULTRASOUND: OVERALL IMPRESSION FOR BOTH LUNGS: READER: IMPRESSION: IMPRESSION RIGHT LUNG LEFT LUNG Normal Yes / No Yes/No Pneumonia Yes/No Yes/No Pleural effusion Yes/No Yes/No Pneumothorax Yes/No Yes/No Others Yes/No Yes/No

32 Impression Lung Anterior Superior Anterior Inferior Lateral Superior Lateral Inferior Posterior Superior Posterior Inferior PLEURAL SPACE Normal Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Pneumothorax Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Effusion Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No LUNG Normal Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Interstitial Disease Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Consolidation Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No If Yes Solid Solid Solid Solid Solid Solid Cavitory Cavitory Cavitory Cavitory Cavitory Cavitory Air Bronchogram Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Static Static Static Static Static Static Dynamic Dynamic Dynamic Dynamic Dynamic Dynamic Mass Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No Doppler (Perfused) Yes/No Yes/No Yes/No Yes/No Yes/No Yes/No

33 X-ray chest X-ray chest taken in PA view; results interpreted by 3 trained radiologists. Radiologists were blinded to patients history & examination findings

34 PATIENT IDENTIFICATION NUMBER: CHEST X-RAY REPORT FORM READER: DATE OF CHEST X-RAY: IMPRESSION: Overall impression for Both Lungs IMPRESSION RIGHT LUNG LEFT LUNG Normal Yes / No Yes/No Lobar Consolidation Yes/No Yes/No Patchy Consolidation Yes/No Yes/No Pneumothorax Yes/No Yes/No Atelectasis Yes/No Yes/No

35 Statistical Analysis o Descriptive statistics analyzed with SPSS version 17.0 software o Continuous variables presented as mean ± SD o Categorical variables expressed as frequencies & percentages o The Pearson's chi-square test or the chi-square test of association used to determine if there was a relationship between two categorical variables o p < 0.05 was considered statistically significant

36 Formula used n = =1.96*1.96*0.8* *0.1 =61.46 o o o o Where p is observed accuracy of point of care PLUS in diagnosis of CAP in children q = 1 p d is the margin of error is the ordinate of standard normal distribution at α% level of significance

37 Results o Total of 112 hospitalized children (CAP) o 100 patients met selection criteria & recruited o 56 (56%) were boys o Mean age + SD of children in yrs was 4.31 ± 4.41 o Radiological diagnosis of pneumonia - 58 (58%) patients o Lung ultrasound was abnormal in 86 (86%) patients

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39 In CXR positive pts, PLUS positive in all (58/ 58) (100%) Whereas, in radiologically (N) pts, but clinically diagnosed CAP, lung ultrasound was abnormal in 28/42 (66.67%) patients Thus, lung ultrasound (LUS) has a high sensitivity (100%) with specificity of 33.3% (for diagnosing radiologically proven cases of CAP) PPV was 67.4%, NPV was 100% & Accuracy was 72%

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41 o Difference in diagnosis of CAP by chest radiology & PLUS, showed the chi square statistic of , with a p value of (highly significant) o Comparison of lung Ultrasound & x ray diagnosis, showed the number of observed agreements to be 72. No of agreements expected by chance was Cohen s kappa coefficient (k) was 0.367, with SE of kappa = % confidence interval: From to o Strength of agreement is considered to be 'fair

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43 Conclusion PLUS is a highly sensitive test in diagnosing CAP It can be used as a first use diagnostic modality in suspected cases of CAP, thus replacing CXR Significantly reduce radiation exposure in this vulnerable pt grp Towards A Radiation Free Pulmonology Practice

44 Acknowledgements - Team Pediatric Team Radiology team Statistician Parul LUS technician Staff Patients

45 Thank You