title: The effects of CO2-insufflation with 5 and 10 mmHg during thoracoscopy on cerebral oxygenation and hemodynamics in piglets: an animal experimental study.
abstract: OBJECTIVE
  To evaluate the effect of CO2-insufflation with 5 and 10 mmHg on cerebral oxygenation and hemodynamics in neonates.
  
  
  BACKGROUND
  An increasing percentage of surgical interventions in neonates are performed by minimal invasive techniques. Recently, concerns have been raised regarding a decrease of cerebral oxygenation in neonates during thoracoscopy as a result of CO2-insufflation.
  
  
  METHODS
  This was an animal experimental study. Piglets were anesthetized, intubated, ventilated, and surgically prepared for CO2-insufflation. Insufflation was done with 5 or 10 mmHg CO2 during 1 h. Arterial saturation (SaO2), heart rate (HR), mean arterial blood pressure (MABP), and cerebral oxygenation (rScO2) were monitored. CFTOE, an estimator of cerebral oxygen extraction ((SaO2 - rScO2)/SaO2)), was calculated. Arterial blood gases were drawn every 15': pre (T0), during (T1-T4) and after CO2-insufflation (T5).
  
  
  RESULTS
  Ten piglets (4 kg) were randomized for 5 (P5) and 10 (P10) mmHg CO2-insufflation. Two P10 piglets needed resuscitation after insufflation, none P5. Linear mixed-effect modeling of paCO2, pH, and SaO2 showed that values were dependent on time and time squared (p < 0.001) but were not different between the 5 and 10 mmHg groups. Analysis demonstrated significant changes over time in heart rate and MABP between the 5 and 10 mmHg groups, with a significant higher heart rate and lower blood pressure in the 10 mmHg group (p < 0.001). For rScO2 and cFTOE, no group differences could be demonstrated, but a significant effect of time was found: rScO2 increased and cFTOE decreased (p < 0.001).
  
  
  CONCLUSIONS
  Insufflation of CO2 during thoracoscopy with 10 mmHg caused more severe hemodynamic instability and seems to be related with a decrease of cerebral perfusion as represented by a higher oxygen extraction. CO2-insufflation of 5 mmHg for thoracoscopy seems to have no adverse effects on cerebral oxygenation.
authors.affiliation: Department of Pediatric Surgery, Wilhelmina Children's Hospital, University Medical Center Utrecht, 3508 AB, Utrecht, The Netherlands, L.J.Stolwijk@umcutrecht.nl.
authors.forename: Lisanne J
authors.initials: LJ
authors.lastname: Stolwijk
authors.forename: Stefaan H A J
authors.initials: SH
authors.lastname: Tytgat
authors.forename: Kristin
authors.initials: K
authors.lastname: Keunen
authors.forename: Nutnicha
authors.initials: N
authors.lastname: Suksamanapan
authors.forename: Maud Y A
authors.initials: MY
authors.lastname: van Herwaarden
authors.forename: Floris
authors.initials: F
authors.lastname: Groenendaal
authors.forename: Petra M A
authors.initials: PM
authors.lastname: Lemmers
authors.forename: David C
authors.initials: DC
authors.lastname: van der Zee
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002245:Carbon Dioxide / Q000008:administration & dosage*; D006439:Hemodynamics; D007327:Insufflation / Q000379:methods*; D010100:Oxygen / Q000378:metabolism*; D011897:Random Allocation; D013552:Swine; D013906:Thoracoscopy / Q000379:methods*
chemical_list: D015415:Biomarkers; D002245:Carbon Dioxide; D010100:Oxygen