PPV

1. PPV Positive Pressure Ventilation by: dr.behzad barekatain Assistant professor of pediatrics neonatalogist Isfahan university of medical science

2. PPV via 1.ambobag 2.ventilator(mechanical ventilation) • Definition & Importance most common approach for treatment of res.failure in both term &pre-term neonate

4. Classification • Volume-controlled ventilator • Pressure-preset ventilator • VOLUME vs PRESSURE VENTILATOR • Pressure ventilator is preferable because of: 1.greater simplicity of design & compact design 2.lower cost 3.simple to operate 4.same pressure in each breathe 5.type of pul.dis in neonate & better responsive to pressure ven.

6. CONTROL (fixed)VARIABLE • Volume: in volume-controlled ventilator • Pressure:in pressure-preset ventilator • PHASE (changeable)VARIABLE • Triggeringاغازگر :شروع دم را کنترل میکند * .time triggering>>>>>in IMV mode (ALS,IVH) .patient triggering>>>>in SIMV OR A/C mode(sensor) • Limitting* محدود کننده فاکتورهای تنفسی یا حداکثر مجاز :وقتی ونتیلاتور به حداکثر مجاز آن متغییر برسد دریچه های تخلیه را باز میکند. • Cycling*پایان دم را کنترل میکند .Volume-cycled .Time-cycled .Pressure-cycled

9. IMPORTANT ISSUSES IN SUCCESSFULLY RES.CARE • 1.operation by device(hardware)>>>5% • 2.principles of physiology(software)>>>95% • 3.other pripheral issues .infection control .nutritional support .fluid & electrolyte management .comfort & pain relief .assessment of circulation .tempreture

10. Procedure for initiating M.V • 1.electrical connection • 2.O2 & air gas source to provide adequate prssure(50 psi) • 3.all connection must fit securely • 4.tube & circuit shoud be specific for ventilator • 5.humidification system Low>>>necrotizing tracheobronchitis High>>>overhydration & increase resistant • 6.temperature 35 to 36 (+,- 2) Low>>>bronchospasm High>>>airway inflamation

11. VENTILATOR CONTROLS • .fio2 • .pip • .peep • .rate • .flow • .Ti ,Te,I/E ratio • .assist sensitivity • .termination sensitivity • .alarm setting • .graphic monitoring • .map • .other(psv,manual breath,hf mode,demand flow)_

12. FIO2 • O2 is the Most commonly usedDRUGinnicu • Inadequate O2 >>>hypoxemia & neurologic injury • ExessiveVARIATION in O2 adm>>>ROP • High level of O2>>>BPD • Depended on disease(eg;MAS or PH) or associated condition(eg;duct depended heart disease) SO • Accurate measurment of O2 (via pulsoximetry or ABG is mandatory in NICU care

13. Peak Inspiratory Pressure (PIP) • Major factor in determining tidal volume(PIP_EDP) in pressure preset vent • Starting level depend on:GA,W,type & severity of disease,lung compl,Resistance,time constant,mode of ventilator,... • Check before & after attachment to patient(2-3 cmh2o) • Appropriate PIP can be judged on examination(chest expantion) and ABG analysis • The lowest PIP that adequately ventilated neonate is optimal

15. PEEP • PEEP stabilizes & recruits lung volume • PEEP improves compliance • PEEP improves V/Q matching • PEEP is selected by physician but maybe altered by other variable .increase rate>>>auto PEEP .decreaseTe>>>increase PEEP .increase airway resistant>>>increase PEEP SO Add to the selected level>>>air traping & ALS • Elevation of PEEP maybe beneficial in pulm hemorrage

18. TIME CONSTANT:RESISTANT.COMPLIANCE • IN RDS:>>>compliance decrease>>>T.C decrease • IN MAS:>>>resistant increase>>>T.C increase

19. Rate (F) • Minute ventilation=rate . Vt>>>↑ Rate >>> ↑ alveolar ventilation >>> ↓PCO2 • Controlled by directly selecting in time-cycled ventilator • ↑ ↑ rate short TE incomplete expiration  gas trapping decresed compliance, intrinsic PEEP ↓VT  ↑PCO2 • Optimal rate:40-60 with Ti:0/3_0/4 sec because of low TC in most pul.disease such as RDS • High rate in PH & low rate in weaning

21. I/E ratio • NORMAL:1/3 – 1/1 • The major effect on  oxygenation • ↑ ratio or even reversed I/E (Ti longer than Te)  ↑ PO2 but its effect is less than change in PIP and PEEP. • CO2 elimination is usually not altered by changes in I/E ratio . • Reversed I/E ratio may lead to increase in the incidence of pneumothorax,co2 retention,decrease co,increase PVR, • Reversed I/E ratio maybe used in CLD because of long TC. • I/E<1/3 maybe used in weaning or MAS

23. Flow • The speed of flow to reach PIP. • Min : at least 2 times the minute volume(./2-1 l/min) .Most pressure ventilators operate at flows of 4-10 L/min. • Low flow (./5-3)>>sine wave>>↓ risk of barotrauma but dead space ven>> co2 retention • High flow >>square wave>> ↑risk of alveolar rupture • Very high flow >>decrease Vt secondry to increased turbulance in high resistant,small diameter ET tube>>Reintubated with bigger ET tube.

25. Wave Forms • Sine wave:more closely to normal spontaneous breathing • Square wave:provide a higher map than do sine waveform if identical PIP used because the PIP is reached more rapidly with square waves.

28. MAP: • (PIP_PEEP).(Ti/Ti+Te)+PEEP

29. Definition of Res.failure Two or more criteria from the following clinical & laboratory categories: .clinical: 1.Retraction(intercostal,supraclavi,suprasternal) 2.Grunting 3.rate>60 4.Central cyanosis 5.Intractable Apnea 6.Decrease activity & movment .laboratory: 1.Paco2>60 mmhg 2.Po2<50 mmhg or O2sat<80%(Fio2=1.0) 3.PH<7.25

30. An aggressive (but gentle)early approach often is preferable in neonates,regardless of their disease. • RDS SCORE: 1.rate(<60:0,60-80:1,>80:2) 2.cyanosis(no in room air:0,no under hood:1,yesunderhood:2) 3.intercostal retraction(no:0,mod:1,severe:2) 4.air exchange(good:0,decreased:1,no:2) 5.grunting(no:0,withstethos:1,withoutstethos:2) <3:O2+follow up 4-6:NICU care + supportive management 6-8:cpap >8:intubation+MV

38. VENTILATOR WEANING • One should think about weaning every day. • Do not increase ventilator days unnecessory • First decrease PIP & Fio2 on A/C mode and when reach to 12 &40% switch back to SIMV mode and then reduce the RATE. • After infant stable for 4-8h & ABG suggest decreasing vetilatory needs. • Before initiation of weaning obtain CXR. • Graphic monitoring & PFT and diuresis is usefull in gauging the capacity for weaning. • Appropriate caloric balance

39. If at any point : FiO2 increased to >60%, ↑spontaneous breathing or distressed with accessory muscle use, agitation or lethargic, hypercarbia weaning should be paused and the support level increased .

40. Extubation • Fio2<40%,RATE:10,PIP:10-12 • NPO for 4 hrs before extubation. • CXR before & 2 and 24 h after ext. • The procedure is carried out by 2 nurses. • Give prolonged sigh of 15-20cmh2Owhile the ET tube is extracted. • Aspiration of NG tube before extubation • ETT & oropharyngeal suctioning to remove secretion and good gag reflex • Prepare emergency equipments (O2, suction, airway, humidifier, emergency intubation equipments) • NPO for 4-6 h after extubation OR until the infant can make an audible cry.

41. Continue • In <1500gr use CPAP after extubation for 2-3 day.in >1500gr placed under oxyhood or nasal o2 with an O2 5% greater. • Watch for several minute after ext.

42. Important observations • Increasing hoarseness • Respiratory stridor • Decrease in saturation(optimal:92-96%) • Increase work of breathing • Increase respiratory rate if yes:reintubated infant and retry 2 day if 2 attempts failed: flexible fibreoptic bronchoscopy ifnegative:dexamethazon (./5mg/kg/day divided in 2dose 48 h before continuing 24 after ext.(methylxanthines?) if several attempts failed:consider laryngotracheomalasia,maybe needs tracheostomy

45. Immediate measures • DOPE • D : Displacement • O : Obstruction • P : Pneumothorax • E : Equipment failure

47. Thanks Thanks