Transcript CPAP Workshop - Pediatric Oncall

CPAP Workshop
Dr. Gautam Ghosh
Dr. Chandan Roy
Dr. Ashok Modi
Dr. Debjani Gupta
Dr. Amit Roy
Dr. Gautam Ghosh
Definition
• CPAP : It is a modality of respiratory
support in which increased pulmonary
pressure is provided artificially during the
expiratory phase of the respiration in a
spontaneously breathing neonate.
• IPPV or IMV : Breathing is taken over
completely by the machine & increased
pulmonary pressure occurs during both
inspiration & expiration.
Dr. Gautam Ghosh
Historical review
• Poulton & Oxam 1936
• Gregory et. Al 1971: first trial
• Agostino et.al 1973 : first RDS managed
with CPAP.
• Bubble & Dual flow CPAP (Infant flow
drive)
Dr. Gautam Ghosh
Types of CPAP
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Oxygen hood
Bubble CPAP & Dual flow
CPAP machine
Ventilator
Dr. Gautam Ghosh
Physiological effects
Organ Benefit
System
Risk
Pulmona FRC / Static compliance /
ry
Pa02
IP Shunt/ WOB / PVR
Splinting airway&
diaphragm /surfactant +++
Air-leak syndrome
/ Decreased
compliance at
high pressure.
CVS/
CNS
VR / CO
ICT/
CPP = MABP( ) --- ICP ( )
Renal
/GIT
Dr. Gautam Ghosh
ADH /Aldos.
Urine / Gut
distension
Various Modes of CPAP
Methods Advantages
Disadvantages
ET Tube
Stable ++/ good control &
ventilator access
Invasive / Airway
resistance ++
Nasal
Prongs
Easy / low resistance
/easy feeding / noninvasive
Septal erosion
/nasal obstruction
/abd. distension
Nasophary Non-invasive / easy
ng. tube
feeding
Mask
Easiest application
CPAP mask
Head box Easy application
Dr. Gautam Ghosh
Leaks /pressure
necrosis/abd.
distension
Oral care difficult
/leak / aspiration
Leak /high flow 02
/ access difficult
Newer CPAP
• Bubble CPAP : vibration (high frequency?)
/ may be less CLD (?)
• Dual flow : Infant flow driver / fluidic flip
mechanism / more stable PEEP control /
failed nasal CPAP – try Dual flow CPAP—
failed –try IMV
Dr. Gautam Ghosh
Effect on Blood gases
• Oxygen : Improves due to increase in FRC
through recruitment of atelectatic alveoli.
• CO2 : Decreases due to availability of
greater surface area for gas exchange due
to recruitment of alveoli. Excessive
CPAP(> 7 cm) leads to over-distension of
alveoli and CO2 retention.
• CPAP improves p O2, p CO2 change is
secondary.
Dr. Gautam Ghosh
CPAP Ranges
Ranges
ET Tube Nasal
Comment
Low
3—4
4—5
CPAP< 3 not useful
Medium
5—7
6—8
Good range
High
8--10
9--10
Adverse effects
common
Fi O2 controlled from 0.2 to 1.0 with CPAP.
Dr. Gautam Ghosh
Indications of CPAP
• Respiratory distress, moderate /severe:
retraction or grunt.
• Recurrent apnea
• P aO2 < 60 with FiO2 > 0.6 ( O2 hood).
• Early : within 2 hrs of distress.
• Late ; after FiO2 requirement > 0.6
Dr. Gautam Ghosh
Guidelines for CPAP
• Start with nasal CPAP of 5—6 cm & FiO2 0.4—
0.5
• Increase CPAP by 1 cm if required
• Reach a CPAP of 8—9 cm.
• Now increase FiO2 in small steps of 0.05 up to
0.8
• Clinical /ABG / SpO2 > 30min in each step
• Do not raise FiO2 before pressure : may remove
hypoxic stimulus -- apnea
• Revert to IMV if not responding
Dr. Gautam Ghosh
Weaning from CPAP
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Reduce nasal CPAP TO 8 cm
Reduce FiO2 by 0.05 to 0.4
Reduce CPAP by 1 cm decrements
Reach a level of CPAP 4cm / FiO2 0.4
Remove CPAP and replace a O2 hood.
Dr. Gautam Ghosh
Optimum CPAP
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Comfortable baby / pink / normal BP
No retraction / grunt
No cyanosis / normal CRT
CRT < 3 SEC
SpO2 > 90-93 %
ABG : PaO2 60-80 / PaCO2 40-45 /p H 7.307.40.
• Diagnosis ; Xray Chest in supine : Post.
Intercostal space 7-8 (if > 8 : reduce PEEP / IF <
5 : raise PEEP)
Dr. Gautam Ghosh
Failure of CPAP
• Retraction / Grunt ++
• Apnea on CPAP
• PaO2 < 50 in FiO2 > 0.8 ( nasal CPAP
>8cm)
• PaCO2 > 55
• Baby not tolerating CPAP.
• Commonest cause : delay in starting
Dr. Gautam Ghosh
Monitoring CPAP
• Clinical : comfort /RR,grunt,retraction
/Cyanosis/HR, pulse / CRT,BP / Temp ./
Abd.girth / Urine / CPAP machine
• Pulse Oximetry ; set alarm at 88%(L) &
95%(H).
• ABG : wait for 15-30 min after each
setting.
Dr. Gautam Ghosh
Practical Points in CPAP
• Warm gases at 34—37* C & humidify.
• Gas flow (21/2 times minute ventilation) at 5-8
L/M minimum
• Look for nasal or oral blocks by secretion
• Oro-gastric suction is a must
• Stabilize the head with a cap and string
• Change CPAP circuit/prong every 3 days
• Asepsis.
• Sedation ??
• Feed : oro-gastric 10 ml/kg EBM
Dr. Gautam Ghosh
CPAP & RDS
• Prevent atelectasis/ preserve surfactant /
avoid IMV
• Early better than late / no role in
prophylactic CPAP
• INSURE : intubate / surfactant /extubate /
CPAP with early signs( a/A o2 <0.36)
• Surfactant by CPAP ; future ??
Dr. Gautam Ghosh
CPAP & Other disease
• CPAP after extubaion : Nasal better than
ET tube CPAP / SNIPP (synchronised
nasal intermittent positive pressure
ventilation)
• MAS : better in atelectatic than overinflated lung
Dr. Gautam Ghosh
Complications of CPAP
• PAL : tends to occur when
O2requirements are decreasing &
compliance improving
• Excess PEEP : V /Q mismatch due to
excess flow in under-ventilated lungs.
Dr. Gautam Ghosh
Future
• With chance of cost of surfactant coming
down in future, CPAP may be a better
alternative in RDS.
• Noninvasive ventilation
Dr. Gautam Ghosh
Case 1
• 30wks, Uncontrolled APH, 30 yrs , 4th
gravida, P 1+2, LUCS, 1 dose Dexa 12 hr
before birth
• BVm with 100% O2for resuscitation,
APGAR 5/1, 8/5. 1280 gms female
• Cord blood PCV 56%, Sepsis screen –ve,
gastric aspirate shake test –ve.
• 1hr: tachypnea, retractions, Spo2 82%
• Put on O2 hood (Fio2 0.5)
Dr. Gautam Ghosh
ABG tree
ABG
CORD
1 HR
(hood)
7.32
6HR
(CPAP)
7.20
14HR
(IMV?)
7.25
p H
7.30
Pa CO2
53
52
45
41
PaO2
39
82.9
55
65
HCO3
25
26
23
16
SpO2
91
90
86
86
Dr. Gautam Ghosh