. . Dr. T.R.Chandrashekar Prof and H.O.D Department of Critical Care Medicine Institute of Gastrointestinal diseases and organ Transplant (IGOT), Bangalore ..
=. Resistance x Flow. +. Compliance. Patient effort.
NMB- controlled ventilation VC/PC. EXTUBATION IS RISKY BUSINESS. WHY THE CONCLUSION OF GENERAL ANESTHESIA CAN BE A CRITICAL EVENT - The anesthesia consultant.
Physiology to understand Mechanical ventilation.
Proportionality of support means support starts and ends and is as much as the Brain wants.
VT-400ml. OP poisoning patient Day-4 stable, on PS mode.
400ml. 20 cm H 2 0. Volume control Assist volume control.
Set-point Adaptive Optimum Servo Intelligent. Targeting Scheme.
350ml. 250ml. Volume support. Test breath. Target Vt 400ml.
Inspiration. Ventilator generates a Inspiratory flow of gas.
Flow occurs. Pressure difference. Flow for a given time = Tidal VOLUME delivered.
Purpose of MV is to put volume into lung. For Volume to get into lungs- flow is required.
Understanding Modes.
1.First question is. Volume modes or Pressure modes.
Flow is delivered till the set volume is achieved.
Fixed Flow Patient may not be comfortable. Peak or Pplat or DP change depending on the alveolar stiffness.
30cm H 2 0 Pplat. Should monitor pressure- Plateau pressure / DP.
Control variables within breaths. Who triggers inspiration? What limits inspiration? What cycles inspiration to expiration?.
1-Who initiates?. Phases of Inspiration. gal_w_accys - 01 - 15hx305dpi.
T:\Brunner\patient.tif. How does the ventilator start a breath? If patient is not capable to initiate a breath Or not allowed to initiate a breath.
Time. Patient. Pressure trigger. Trigger – Initiation of Inspiratory flow from the ventilator.
Pressure Triggering. Time (sec). Assisted. Controlled.
Improper trigger setting is responsible for >50% asynchrony.
3. When is inspiration ended allowing for expiration to start ? (CYCLE VARIABLE).
Time cycled. Pressure controlled. Preset V T Volume Cycling.
Flow Cycling. Peak flow. 75. 50. 25. 100L. Inspiration.
DIFFERENT TYPES OF BREATHS depending upon the above three questions.
T. L. C. All three stages controlled by machine. T.
PIP. FIO 2 I:E VC/AVC Mode VT 7ml/kg PEEP RR 50% 450ml 6 cmH 2 O 18/min 1:2 DP 8 Insp Hold Cs 56.25 Pplat 14.
Controlled Mode (Volume-Targeted Ventilation). DR TRC/KRH.
Pressure Flow Volume (L/min) (cm H 2 O) (ml). Set PC level.
Pplat. How set Pressure limit when shifting from Volume limited modes.
Pressure support mode. You can not set RR Tidal volume= altering PS levels I:E ratio Instead we can change Rise time and Expiratory sensitivity to alter them.
Expiratory trigger sensitivity. Rise time To increase flow.
Basic More Apnea TRC Patient I:E: 128 TE: 2.75S VVIBW: 8.0 ml/kg 7 cmH20 70 p- ramp 25 1.00 5.0 b' min Flow trigger 16 530 5 cmH20 PEEP/CPAP 50 O xygen Cqntrols.
Change from inspiration to expiration phase. Types of cycling?.
RR and I:E ratio is controlled by whom?. RR ,I:E ratio Are controlled by the patient.
Flow Cycling. 75. 50. PF=100%. 25. Inspiration. Expiration.
RISE TIME. 40. P CIRC cmH 2 O. INSP. L min. EXP. 30.
PEAK FLOW. Peak Flow 30l/mt. Peak Flow 90 l/mt. Missed breaths.
Time (sec). Flow (L/m). Flow Cycling. Pressure (cm H 2 O).
SIMV=VC+PS. Breathing sequence - Whether or not the mode allows mandatory, spontaneous breaths or both.
SIMV. Give rest to respiratory muscles during mandatory breath= decreased WOB Has back up rate, so when starting to wean you feel it much safer.
Time (sec). DR TRC/KRH. Time-Cycled. Flow-Cycled.
Mandatory breath Spontaneo b reaths Flow (L/min) Volume 30 Airway pressure (a-n H 20) Esophageal pressure (cm H 20) Figure 15-10 S',mchronized intermittent mandatory ventilation. Note that the esophageal pressure change for the mandatory breath is nearly as great as that for the spontaneous breaths..
Flow (L/min) Time. SIMV+PS. Asynchrony Diaphragmatic injury.
PC with PEEP I:E=1:1 With spontaneous breathing at both levels.
Settings that the clinician selects. The alarms that place limits on the process.
Tidal volume 6 to 8ml/Kg. PEEP 5cm H2O Personalize.
Same tidal volume. 2. PEEP =5 cm H2O. Can be personalized looking at Pplat and driving pressure.