NAVA-korzyści dla noworodka

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1 DISCLOSURE No conflict of interest related to this topic NAVA-korzyści dla noworodka Jan Mazela Poznan University of Medical Sciences Poznan, Poland EUROPE POZNAŃ and WIELKOPOLSKA REGION POLAND WIELKOPOLSKA REGION Poznan Univ of Med Sciences NICU POZNAŃ 4 mlnlevel level III center (7 level II and 24 level I) 7 deliveries 4 outborn admissions 9 NICU admissions 377 NICU beds 1

2 Intro/basics How it looks/how it works? Status quo in the literature How to tune-up NAVA ventilation Ventilation Induced Diaphragm Dysfunction Impedance Pneumatic Capsule Pressure Comparison of Triggering Methods Method Advantages Disadvantages No added dead space, noninvasive Poor sensitivity, many artifacts Rapid response, no extra dead space, leak tolerant No added dead space, leak tolerant Positioning is critical, no longer commercially available Poor sensitivity, long trigger delay, high WOB Airflow Very sensitive, rapid response Added dead space, leak sensitive Diaphragm EMG - Edi Sensitive, most rapid response, leak tolerant Requires careful positioning of probe State of the art in mechanical ventilation, Keszler, J of Perinatology (9) 29, NAVA neurallyadjusted ventilatory assist How NAVA works The ventilator generates the peak inspiratory pressure based on the amount of electrical activity generated by the diaphragm The PIP is generated until the electrical activity decreases by 4 to 7% and then the breath is terminated The baby therefore determines the peak inspiratory pressure, the inspiratory and termination time for each breath and the respiratory rate 2

3 NAVA Terminology EADi Electrical Activity of the Diaphragm Abbreviated as Edi Edi Peak -peak electrical activity tells you about the neural inspiratory effort Edi Min tonic electrical activity believed to play a role in preventing de-recruitment of the lung (Allo 6, Emeriaud, Beck 8) NAVA Terminology NAVA level -Conversion factor that translates the Edi from an electrical signal to a peak inspiratory pressure (PIP) Calculated by: PIP = NAVA level x(edi peak Edi min) + PEEP Edi trigger the change in Edi needed to trigger the ventilator to deliver a breath NAVA Terminology PIP = NAVA level x(edi peak Edi min) + PEEP NAVA level 2 Edi peak 12 Edi min 2 PEEP 5 PIP = 2x (12 2) + 5 = 2x () + 5 = 25 mmhg Brainstem senses decreased ph or increased pco2 wants to increase tidal volume increases the electrical signal to the diaphragm NAVA level 2 Edi peak 15 Edi min 2 PEEP 5 NAVA Terminology PIP = NAVA level x (Edi peak Edi min) + PEEP NAVA level 3 Edi peak 12 Edi min 2 PEEP 5 PIP = 3x (12 2) + 5 = 3x () + 5 = 35 mmhg Brainstem senses increased ph or decreased pco2 wants to decrease tidal volume decreases the electrical signal to the diaphragm NAVA level 3 Edi peak 8 Edi min 2 PEEP 5 PIP = 3x (8-2) + 5 = 3x (6) + 5 = 23 mmhg PIP = 2x (15-2) + 5 = 2x (13) + 5 = 31 mmhg 3

4 Conventional Ventilation Patient Controls using Flow Trigger: Initiation of Breath Rate (in some modes) Ventilator Controls: Peak Pressure or Tidal Volume Inspiratory Time Termination of Breath PEEP Minimum Rate FiO2 NAVA Ventilation Patient Controls using Neural Trigger: Initiation of Breath Inspiratory Time Rate Peak Pressure Termination of Breath Ventilator Controls: FiO2 PEEP Health Neuroventilatory coupling μv μv μv Disease Synchrony: Only for Initiation of Breath Asynchronous for Many Breaths False Triggering Synchrony: Initiation of Breath Size of Breath Termination of Breath Edi V T ml ml ml NAVA is not only about triggering Neural Control of Ventilatory Assist (NAVA) Neuro-Ventilatory Coupling Central Nervous System Phrenic Nerve Diaphragm Excitation Diaphragm Contraction Chest Wall and Lung Expansion Airway Pressure, Flow and Volume Ideal Technology New Technology Current Technology Ventilator Unit 4

5 Edi Catheter Edi catheter preparation 1. Connection to Edi cable 2. Nutrition feed 3. Evacuation (only 12 and 16 Fr) 4. Reference electrode 5. Electrodes (9) 6. Holes for nutrition/evacuation 7. Inter Electrode Distance (IED) 8. Lumen for electrodes 9. Sump lumen (only 12 and 16 Fr). Feeding lumen 11. Barium strip for X-ray identification 12. Coating for easier insertion and better electrical conductivity (indicated in the picture with light blue) 13. Scale in centimeters from the tip Fr (French) = circumference of the catheter in mm Ventilator set-up Catheter positioning 5

6 Catheter positioning 2 NAVA ventilation tuning NAVA ventilation tuning 6

7 How does it work in real life? Status quo in the literature 235 peer reviewed manuscripts Latest systematic review: Beck J, et al. Minnerva Anestesiologica 16; 82(8):874 Clinical studies on newbrons: Invasive NAVA: 6 studies (n=6 baies); GA=24weeks, bw=728g Non-invasive NAVA: 2 studies (n=17 babies); GA=24 weeks, bw=812g Results: Limits PIP and TV Superior patient-ventilator interaction Electrode Array in Neurally Adjusted Ventilatory Assist (NAVA) Sinderby et al, Nature Medicine 1999; 5(12):

8 Mechanical ventilation induces prolonged neural expiratory time Mechanical ventilation induces prolonged neural expiratory time 14 patients with ARDS Draeger Babylog 8 Trigger Flow L/min Eadi measured with esophageal electrodes CONCLUSIONS: No reflex deactivation of the diaphragm during SIMV 53% infant-ventilator asynchrony of the total breath Asynchrony associated predominantly with expiratory asynchrony Online monitoring of diaphragm activation during IMV Beck, J., et al., Pediatr Res, 4. 55(5): p Beck, J., et al., Pediatr Res, 4. 55(5): p NAVA improves synchrony and respiratory unloading NAVA improves synchrony and respiratory unloading NAVA lo NAVA hi PSV lo PSV hi 12 New Zealand rabbits (ARDS lung lavage model) Servo I (VT=6 ml/kg, RR=, FiO 2 =.5, PEEP=2 cmh 2 O) Incremental PSV and NAVA run for each animal CONCLUSIONS: NAVA requires small increase in airway pressure to unload the diaphragm NAVA interferes less with natural breathing pattern than PSV Beck, J., et al., Pediatr Res, 7. 61(3): p Beck, J., et al., Pediatr Res, 7. 61(3): p

9 NAVA in LBW infants NAVA in LBW infants 7 premature infants < 36 weeks ga 5F oro-gastric tube Conventional ventilation group: Babylog Draeger, PSV NAVA group: Servo with NAVA: Intubated ET tube, NAVA matched PIP Non-intubated SNP tube, NAVA adjusted to reach this same delta IP CONCLUSIONS: Patient-ventilator synchrony not affected by the presence of leak Interface with less leak would increase the efficiency of non-invasive ventilation with NAVA NAVA PSV PSV+VG NAVA NIV NAVA PSV+VG NIV NAVA Beck, J., et al., Pediatr Res, 9. 65(6): p Beck, J., et al., Pediatr Res, 9. 65(6): p Synchrony is not affected by leaks during non-invasive ventilation Patient-ventilator synchrony in children Beck, J., et al., Pediatr Res, 9. 65(6): p Beck J, et al. Minnerva Anestesiologica 16; 82(8):874 9

10 Edi Catheter positioning procedure Edi Catheter positioning window Fine-tune the settings in Pressure Support Four ECG waveforms for Edi catheter position Edi waveform Scale and sweep speed settings Freeze function Numerical values of Edi peak and Edi min Trigger Edi Trigger Edi zawsze na.5 uv NAVA estimation

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12 NAVA titration Starting at NAVA=.5 => every 3 minutes increases until NAVA=4 Edi from 1 premie Edi from all premies Edi Peak and Minimum Neonates >37 weeks with no active respiratory problems and feeding normally * * * P <.5 Firestone KS, et al. J Perinatol 15;35:612e6. Stein,Wilmoth and Burton NAVA optimization Optimize the NAVA level according to Edi max, which should be targeted between 5-15 μv. -If Edi max is < 5 μv, decrease the NAVA level. -If Edi max is > 15 μv, increase the NAVA level. The changes in NAVA level should be.1-.2 cmh2o/μv at a time. The changes in NAVA level are mediated in a few breaths to Edi max. The usual NAVA level is.5 2. cmh2o/μv. Beck J, et al. Minnerva Anestesiologica 16; 82(8):874 12

13 Setting up PEEP Initially, set the same PEEP as in the previous ventilatorsettings. If Edi min is constantly > 1 μv (as a sign of tonicdiaphragmatic activity to maintain FRC), increase PEEP. Setting up apnea time Set the initial apnea time at 5 seconds. If breathing isirregular and the patient unstable, you may decreaseapnea time down to 2 seconds. This will result in backupbreaths after each 2-second apnea until next spontaneous breath indicated by Edi signal occurs. However, make surethat the backup ventilation does not hyperventilate thepatient preventing spontaneous breathing efforts (whichwould keep the patient unnecessarily on backup ventilation). Back-up settings A shorter apnea time (<5 seconds ) increases the significanceof backup ventilation, as there is a risk for hyperventilation.this does not usally occur with NAVA ventilation. Adjust the backup settings appropriately taking intoaccount the pre-nava settings and the recovery process of the patient. Weaning patients from NAVA Decrease the NAVA level as the patient s pulmonary statusimproves. Usually, the patient is ready to be extubatedwhen the NAVA level is.5 cmh2o/μv. 13

14 NIV NAVA in practice The NAVA levels in NIV NAVA are usually lower than ininvasive NAVA (.5 1. μv/cmh2o). Higher NAVA levelsmay increase the amount of gas entering the stomach/intestine and cause abdominal distention. -If Edi max is < 5 μv, decrease the NAVA level. -If Edi max is > μv, increase the NAVA level. The changes in NAVA level should be.1-.2 μv/cmh2o ata time. Usually, patient can be switched to ncpap, whenthe NAVA level is <.5 cmh2o/μv. NIV NAVA 14

15 NIV NAVA NIV NAVA NIV CPAP When using ncpap NAVA set-up NAVA= 15

16 2d of life, 75g, 1 dose of Survanta 35 PIP decreases when on NAVA 35 Peak airway pressure [cmh₂o] : 19: : 21: 22: 23: : 1: 2: 3: 4: 5: 6: Peak airway pressure [cmh₂o] : 17: 18: 19: : 21: 22: 23: : 1: 2: 3: 4: 33 weeks, 226 gm, RDS, NAVA weeks, 214 gm, CLD, NAVA 5 5 Peak airway pressure [cmh₂o] : 13: 14: 15: 16: 17: 18: 19: : 21: 22: 23: : Peak airway pressure [cmh₂o] 4 18: 19: : 21: 22: 23: : 1: 2: 3: 4: 5: 6: weeks, 115 gm, RDS and pneumothorax, NAVA 2 3 month old ex 28 week infant with pulmonary hypoplasia, NAVA 2 Dynamic Compliance improves on NAVA Neonates with Acidosis - on SIMV/PC and then on NAVA 3 1,5 Dynamic compliance [ml/cmh₂o] Dynamic compliance [ml/cmh₂o] 2,5 2 1,5 1,5 1,2 1,8,6,4,2 18: 16: 19: 17: : 18: 21: 19: 22: * : * 23: 21: : 22: 1: 23: 2: : 3: 1: 4: 2: 5: 3: 6: 4: Dynamic compliance [ml/cmh₂o] Dynamic compliance [ml/cmh₂o] 1,2,9,6,3 12: 2 1,5 1,5 18: 13: 19: 14: * : 15: * 21: 16: 22: 17: 23: 18: : 19: 1: : 2: 21: 3: 22: 4: 23: 5: : 6: 7,45 7,4 7,35 7,3 7,25 7,2 7,15 7,1 7, P =.18 SIMV/PC ph < 7.38 NAVA P =.8 SIMV/PC NAVA pco2 >

17 Neonates with Alkalosis - on SIMV/PC and then on NAVA Neonates with normal ph and pco2 - on SIMV/PC and then on NAVA 7,55 P =.4 5 P =.5 7,5 P =.45 6 P =.82 7,5 7,45 7,4 7, ,45 7,4 7, ,3 SIMV/PC ph > 7.42 NAVA SIMV/PC NAVA pco2 < 35 7,3 SIMV/PC NAVA ph SIMV/PC NAVA pco NAVA allows neonates to wean their own PIP over time Improved Compliance over time on NAVA Peak airway pressure [cmh₂o] Peak airway pressure [cmh₂o] : 19: 7: : 8: 21: 9: 22: : 23: 11: : 12: 1: 13: 2: 14: 3: NAVA : 4: 16: 5: 17: 6: Peak airway pressure [cmh₂o] : 3: 4: 5: 6: 7: 8: 9: : NAVA.5 NAVA 2 NAVA 3.2 Peak airway pressure [cmh₂o] : 8: : 12: 14: 16: 18: : 22: 11: : 12: 2: 13: 4: 14: 6: Dynamic compliance [ml/cmh₂o] Dynamic compliance [ml/cmh₂o] 2,3 2 1,7 1,4 1,1,8,5 3 2,5 2 1,5 1,5 6: 19: 7: : 8: 21: 9: 22: : 23: 11: : 12: 1: 13: 2: 14: 3: 15: 4: 16: 5: 17: 6: Dynamic compliance [ml/cmh₂o] Dynamic compliance [ml/cmh₂o] 2,5 2 1,5 1,5 1,5 1,2,9,6,3 2: 6: 3: 8: 4: : 5: 12: 6: 14: 7: 16: 8: 18: 9: : : 22: 11: : 12: 2: 13: 4: 14: 6: 17

18 Diaphragm activity 18

19 Summary Neonates appear to have intact neuro-ventilatory coupling with functional feedback pathways. Patient selection is important not all neonates are candidates for NAVA and, some may not be candidates all the time(sedation, PPHN, IVH, CNS) Many neonates ventilate on NAVA with lower PIP (TV) and FiO2 then on conventional ventilation. Summary Many neonates improve their blood gases on NAVA despite ventilating with lower pressures. Many neonates decrease their own PIP (TV) over time while on NAVA auto weaning Many neonates have improved compliance on NAVA. In this small number of patients no significant complications or side effects were noted while on NAVA. NAVA WORKS IN NEONATES! But does it make a difference to outcomes? Thank you Large multi-center trials are needed to answer questions if: NAVA decreases time on ventilators? NAVA decreases the incidence of chronic lung disease? Is it helpful for MIST/INSURE? 19