Chandra Ramamoorthy MBBS; FRCA (UK) Professor of Anesthesiology, Stanford University. Director of Pediatric Cardiac Anesthesiology

Transcription

1 Should NIRS be Standard Care for Pediatric CPB Chandra Ramamoorthy MBBS; FRCA (UK) Professor of Anesthesiology, Stanford University Director of Pediatric Cardiac Anesthesiology Stanford Children s Hospital Stanford CA March 2015, Phoenix

2 Disclosures Past Speaker: Somanetics Corp. Clinical Researcher: Nonin Inc Masimo Inc

3 Audience Question-1 Use of cerebral oximetry during CPB is routine Yes No

4 Audience Participation Question -2 The level of evidence supporting routine use of pulse oximetry is 1 A True False

5 Audience Question-3 In cyanotic patients most pulse oximeters are inaccurate, hence I : A) Add oxygen when I am uncomfortable with the value B) I use a special sensor for cyanotic patients that s more accurate C) Accept the inaccurate value and intervene when the Heart rate drops.

6 Cerebral Oximetry Near Infra red light source nm Detectors-2 Optical length Absorption of light by HbO2 /Hb Validated: Jugular Bulb Oximetry Venous weighted saturation : 70:30

7 Cerebral Oximeters: FDA Approved Commercial Devices Invos, Somanetics Foresight,Casme d Equanox, Nonin Inc Masimo Inc Light Source Wavelength LED 2 Laser 4 LED 4 LED 4

8 Critical Values Normal : 60-70% (2/3rd SaO2) Kurth, 2002, piglets: Lactate, EEG, ATP reduction: 33-44% ScO2 Duration of Ischemia and Extent affect outcomes (Kurth, 2007)

9 Variations in cerebral oximeters Light Source : LED vs laser Number of wave lengths : 2-4 Distance between emitter and detector Proprietary algorithm Devices display proportional bias : under vs over detection All of the above leads to variations in values making comparisons difficult

10 Cerebral Oximetry Use Case reports Retrospective case-control studies Expert Opinion Consensus statement Randomized control trial

11 Clinical Outcome Data in Children Austin et al 1997: Improved neurological outcomes in children after OHS retrospective, case-control study Evidence Level 2b: benefits outweigh risks

12 Clinical Outcome Data in Children Dent et al 2006, J Thorac Cardiovasc Surg Single Ventricle n=22 Pre and Post: Neuro exam, EEG, Brain MRI Prolonged post op rso2% <45% for >er than 180 mins associated with new MRI brain lesions (n=14)

13 Clinical Outcome Data Andropoulos: J Thorac CV Surg: 2010, Single and 2 Ventricle pts EEG, MRI and NIRs, Standardized anesthetic 2V patients with low rso2 post-op = 0 50% SV with prolonged low rso2 Prolonged rso2 not associated with MRI changes in all but only 1/3rd

14 Cerebral Oximetry-Use in Children undergoing CPB? Adverse effects despite its use STS Task Force : Not Unanimous Evidence level 3: Not beneficial Evidence level 2B: Benefits outweigh risk No level 1A evidence Cost vs Benefit

15 CCAS Data Data between ; CPB & No CPB Roughly 25,000 cases reported Roughly 17,000 had neuro-monitoring In 80% of cases NIRS mornitoring was used 6% BIS; <1 TCD Incomplete data reported David Vener MD, Texas Children s Hospital

16 Improve Data collection Data not being collected on cannulae re-position Changes to CPB Hb Temperature PaCO 2 Anesthetic technique Vasopressors GOLD Standard: RCT

17 Has the time come to use near-infrared spectroscopy as a routine clinical tool in preterm infants undergoing intensive care? N=4000 Cerebral oximetry must reduce the risk of a clinically relevant endpoint, such as death or neurodevelopmental handicap Ultimate way of demonstrating the added value is by a randomized trial October 2011

18 Pulse Oximetry Introduced Routine continuous pulse oximetry monitoring did not reduce transfer to the ICU and did not decrease mortality, and it is unclear whether any real benefit was derived from the application of this technology for patients

19 Pulse Oximetry Variations between oximeters- Nellcor, Masimostandard and blue sensor Most are calibrated using volunteers and hypoxic mixtures Below 85% accuracy decreases When compared with co-oximeter-gold standard, significant variation at lower saturation

20 Oximetry: Monitoring the Brain as an Index organ. John M. Murkin, M.D., F.R.C.P.C Editorial Are we asking the right questions? Should we be using cerebral oximeter as overall index of tissue oxygen supply?

21 Conclusion Cerebral oximetry is an innovative technique to assess oxygenation of the brain Inter-individual variations in values and between individual variations are poorly understood Risk Benefit ratio is favourable despite cost Continue to work on understanding and improving the technology

22 Audience Question Do you think Cerebral oximetry should be added as a standard monitor during CPB Yes No Thank You