Search
 
 

Key Study Findings - Pediatric Surgery/ICU

The following Key Study Findings are just a sample of the more than 600 compelling clinical presentations, study abstracts and published papers documenting INVOS® System benefits.

To see the full bibliography, please visit Clinical Evidence.

Peri-Operative Death Associated with Low rSO2



This 20-month retrospective study of 143 INVOS® System monitored preoperative infants and children found that:
  • Low pre-op rSO2 value (<51) predicted perioperative death in children with congenital heart disease.
  • Pre-op optimization of rSO2 provides the care team an opportunity to improve outcome.
  • This data may also affect surgical decisions and parent counseling.
Footnote:
Fenton KN, et al. Am J Surg. 2005 Aug;190(2):260-263.

rSO2 Trends Approximated SvO2 Trends


This comparison showed that the average of noninvasive cerebral and somatic rSO2 closely estimated changes in the invasive SvO2 value.
  • The authors state rSO2 technology "addresses a number of the limitations of SvO2 monitoring." For example, "Two-site NIRS monitoring reveals profound differences in tissue oxygenation in different organ beds" (i.e., cerebral-somatic).
  • A number of other studies have also demonstrated rSO2 as a noninvasive indicator of SvO2 trends in children and infants.
  • Kirshbom and colleagues studied the INVOS® System cerebral oxygen measurement as a predictor of superior vena cava oxygen saturation measured during cardiac catheterization in single ventricle children. They found the agreement between venous gas sampling and cerebral oximetry to be positively correlated. In a stepwise multiple regression analysis, rSO2 was the only significant predictor of SVC saturation (p=0.009). Kirshbom PM, et al. Pediatr Cardiol. 2007 Jan-Feb;28(1):42-5.
  • Simsic and colleagues showed a positive relationship between mixed venous oxygen saturation and NIRS in high risk congenital heart pediatric patients, both before and after surgery. Linear regression R value of 0.6; R2 of 0.4; p<0.001. Simsic JM. Cerebral oximetry via near-infrared spectroscopy: A non-invasive indicator of mixed venous oxygen saturation in neonates before and after cardiac surgery. INVOS® Cerebral Oximeter Clinical White Paper Series 2005;412(1):1-4.

Footnote:
Hoffman GM, et al. Semin Thorac Cardiovasc Surg Pediatr Card Surg Annu. 2005;8:12-21.

Peri-renal rSO2 and Renal Dysfunction


The relationship between renal/somatic INVOS® System monitoring in the early post operative period and the presence of later renal dysfunction in a group of high-risk cardiac patients was examined in this study.
  • INVOS® System SomaSensor® probes were placed over the kidney for peri-renal validation.
  • Low rSO2 on post-op day 1 (POD1) was associated with renal dysfunction on post-op day 3 (POD3).
  • Risk of doubling POD3 creatinine was 8 times greater for each hour of somatic rSO2 < 60 (p < 0.001).
  • With multiple linear modeling, peri-renal rSO2 remained the most significant predictor (p < 0.001) of renal dysfunction.
    • The investigators state, "Data provided by NIRS was a more robust indicator than ABG analysis, SaO2, SvO2, mean blood pressure, central venous pressure, heart rate and PetCO2."

Footnote:
Hoffman GM, et al. Anesthesiology 2005;103:A1327.

Detection of Ischemia Caused by Mechanical Obstructions

An abrupt decrease in regional cerebral saturation index (rSO2i) occurred at the onset of CPB. After repositioning of the aortic cannula, rSO2i recovered to baseline levels.

Cerebral monitoring with the INVOS® System allows care teams to quickly detect and correct cerebral ischemia, including that due to mechanical obstructions, thereby potentially improving the patient's outcome.
  • Gottlieb and colleagues describe how using the INVOS® System bilaterally on a 16-month old congenital heart patient helped them quickly identify and rectify a misplaced aortic cannula associated with falling rSO2 values.
    • The authors state, "We feel that the aortic cannula malposition would not have been detected using standard physiologic monitors and that NIRS monitoring should be used routinely during pediatric cardiac surgery."
    • Furthermore, the authors state, "Bilateral monitoring of cerebral oxygen saturation resulted in the prompt recognition of aortic cannula malposition" showing that in this case, the INVOS® System provided timely detection of potential complications and offered a better chance at a positive outcome.
Footnote:
Gottlieb EA, et al. Paediatr Anaesth. 2006 Jul;16(7):787-9.
www.wiley.interscience.com