1 / 27

Critical Care Journal Club

Critical Care Journal Club. 26.07.2013 Ruth Brown CT2. Background. Vibration Response Imaging (VRI) Non invasive No radiation exposure Sensors detect vibrations during inspiration and expiration and transforms this into a grey scale image Different diseases display different patterns

ovid
Download Presentation

Critical Care Journal Club

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Critical Care Journal Club 26.07.2013 Ruth Brown CT2

  2. Background • Vibration Response Imaging (VRI) • Non invasive • No radiation exposure • Sensors detect vibrations during inspiration and expiration and transforms this into a grey scale image • Different diseases display different patterns • Darker the colour the higher the vibration intensity Fancy stethoscope??

  3. Hyperlink:http://youtu.be/NGldu-1ya9g • Israeli Firm: Deep Breeze • Approved for EU in 2005 and US in 2007 • Main use and focus in trials has been for thoracic surgery • Wireless ‘home’ version now made (iPad compatible) • VRI(XP) system is used in the study, which was conducted in China

  4. Question • Is VRI a useful tool in evaluating the initial therapeutic effect of non-invasive positive pressure ventilation in patients experiencing an acute exacerbation of COPD?

  5. Method • Single center study • Two patient groups: • Healthy volunteers (39) • Patients experiencing an acute exacerbation COPD (36/19 smokers) • Pts were recruited from respiratory wards or the ICU of the ED • It is not known over how long a time period data collection occurred

  6. Inclusion/Exclusion Criteria • Volunteers: • Inclusion: • No resp/cardiac dx • No resp infection for 1/12 • Non smoker • Pulmonary function: FEV1/FVC>75%, FEV1%>80%, FVC% >80% predicted

  7. Exclusion: • Severe deformity of thorax or spine • Hypertrichosis • Skin injury on the back • Gestation/lactation • PPM/Defib • Male to female ratio 2:1 • Mean age 36.5+/- 13.2 years • Mean height 1.64+/-0.08 M • Mean weight 67.4+/-10.9 kg

  8. Patients (AECOPD): • Inclusion: • Change in baseline dyspnoea, cough &/or sputum production exceeding the normal range (according to 2007 GOLD guideline) • T2RF with pH >7.20 • Patients who had not had NPPV before • Patients who met ‘basic requirements’ • Conscious • Cooperative • Little secretions • Intact independent cough and expectoration • HD stable

  9. Exclusion: • Absolute CI for NPPV: • High risk aspiration • Weak airway protection • Cardiac and respiratory arrest • Trauma • Burns • Physical deformity • Recent surgery – face, neck, oropharynx • Upper airway obstruction

  10. Relative CI: • Failure to cooperate with NPPV • Severe hypoxaemia • Dysfunction of the extra-pulmonary visceral organs • Intestinal obstruction • Recent operation – oesophagus, epigastrium • Patients who refused NPPV • Difficulty in sensor placement – skin conditions, thoracic/spinal deformities, gestation/lactation, PPM/Defib • Failure to tolerate NPPV for >2hrs and have VRI examination performed 3 times

  11. Male to female ratio 2:1 • Mean age 58.34 +/- 14.72 years • Mean height 1.62+/-0.09 M • Mean weight 61.5+/-13.5 kg • CXR abnormal in 26 patients • Pleural effusion • Pulmonary consolidation – 10 of which were multi-lobar

  12. Procedure • All had Hx and examination • Healthy Volunteers: • AECOPD Patients:

  13. VRI data collection • VRI(XP) Deep Breeze System used • VRI did not interrupt NPPV in either group • Participants were told to breathe by mouth • Data was collected during the 1st 12 seconds of recording with VRI • Grey scale images were produced (aka dynamic vibration energy figure) in 71 frames per 12 seconds recorded

  14. Image Analysis • The lungs were divided into 6 areas, i.e. upper, middle, lower bilaterally • Quantitative Lung Data (QLD) is produced which gives the mean and total vibration energy for each area • The Maximal Energy Frame (MEF) was the frame when vibration energy reached its peak in the inspiratory phase

  15. Expiratory Vibration energy Peak (EVP) was used to observe synchronicity between the lungs • The images frames were analysed individually as was change in the QLD and the shape of the MEF image also studied • 3 VRI trained clinicians conducted a blinded image analysis independently – unaware of pt information, if T1-4, or other evaluations

  16. Image Scores • Abnormal VRI images scores (AVRIS) were calculated based on numerous features including variations in the vibrational energy curves in inspiration and expiration, air trapping, dyssynchrony, MEF image shape and expiratory vibration energy peak. • Note some aspects are subjective

  17. Results • Statistical analysis was performed • High repeatability between in the 3 evaluators (P<0.05) • In healthy volunteers there was no statistical difference between T1 and T2 using AVRIS • In AECOPD pts mean total of AVRIS at T2 was significantly lowered than pre NPPV at T1showing improved ventilatory function • HR, RR, VAS and SAMU scores at T2 were significantly lower than those at T1 but no significant difference between T4 and T2

  18. A positive correlation was between PaCO2 changes at T3 Vs T1 and AVRIS changes at T2 Vs T1

  19. They comment that significant changes can be noted earlier in VRI image (at T2) than with blood gas analysis and so VRI may be an effective method for evaluating the initial therapeutic response…(but they didn’t check an ABG at T2, they took at at T3) • NPPV was stopped in 4 patients as they either failed to respond or deteriorated (a decision determined by ABGs at T3) – 3 patients received a tracheostomy and 1 died. All were noted to have excessive secretions and poor cough. • The remaining 32 all survived to discharge

  20. Observations…. • Inclusion criteria for patients does not mention a previous diagnosis of COPD confirmed with spirometry • Volunteer or control group were 20 years younger than the patient group • There is no comment on the cause of COPD in the non-smoking patients • AVRIS – some components in developing the score were subjective, but it was found to be repeatable and statistically significant • Lack of clarity, e.g. SAMU score not explained • Exceptional number of acronyms

  21. Limitations • Single center study • Small population group • Our population group is different as mean weight >61kg and may have other causes for T2RF in addition to COPD such as OSA

  22. Conclusions • Did they answer their question? • Yes, VRI could be used as a supplementary tool to assess initial therapeutic response based on their findings • Is it likely to change current practices in this critical care department? • No. • More studies needed especially in relation to our patient demographics • Cost – equipment, training, implementing, nursing time with additional scoring systems • Practicalities of using the VRI – nurses taken away from other L2 patients

  23. Any Questions?

  24. Resources: • http://europepmc.org/articles/PMC3478983/ • http://www.businesswire.com/news/home/20081003005034/en/Deep-Breeze-Announces-Latest-Study-Results-Vibration • http://israel21c.org/health/deep-breeze-breakthrough-lets-patients-breathe-easy/ • http://cancergrace.org/forums/index.php?topic=5740.0;wap2 • http://www.medscape.com/viewarticle/778242_1 • http://en.wikipedia.org/wiki/Imaging_Lung_Sound_Behavior_with_Vibration_Response_Imaging#cite_note-5

More Related