Intensive Care Medicine

, Volume 38, Issue 2, pp 316–323

Xenon offers stable haemodynamics independent of induced hypothermia after hypoxia–ischaemia in newborn pigs

  • Elavazhagan Chakkarapani
  • Marianne Thoresen
  • Xun Liu
  • Lars Walloe
  • John Dingley
Experimental

DOI: 10.1007/s00134-011-2442-7

Cite this article as:
Chakkarapani, E., Thoresen, M., Liu, X. et al. Intensive Care Med (2012) 38: 316. doi:10.1007/s00134-011-2442-7

Abstract

Purpose

To assess the effect of 18 hour (h) 50% xenon (Xe) inhalation at normothermia (NT, 38.5°C) or hypothermia (HT, 33.5°C) on mean arterial blood pressure (MABP), inotropic support and heart rate (HR) following an induced perinatal global hypoxic−ischaemic insult (HI) in newborn pigs.

Methods

Newborn pigs ventilated under inhalational anaesthesia, following a 45 min HI (inhaled oxygen fraction reduced until amplitude integrated electroencephalogram was less than 7 μV), were randomised to three Xe (n = 45) (50% Xe 18 h with NT, HT 12 h or HT 24 h) or three non-Xe groups (n = 53) (0% Xe with NT, HT 12 h or HT 24 h) under otherwise identical conditions. We measured MABP and HR every minute. Hypotension (MABP <40 mmHg) was treated sequentially with 2 × 10 mL/kg saline, dopamine, norepinephrine and hydrocortisone if required.

Results

Xe maintained higher MABP during HT (5.1 mmHg, 95% CI 2.34, 7.89), rewarming (10.1 mmHg, 95% CI 6.26, 13.95) and after cessation (4.1 mmHg, 95% CI 0.37, 7.84) independent of HT, inotropic support and acidosis. Xe reduced the duration of inotropic support by 12.6 h (95% CI 5.5, 19.73). Inotropic support decreased the HR reduction induced by HT from 9 to 5 bpm/°C during cooling and from 10−7 to 4−3 bpm/°C during rewarming. There was no interaction between Xe, HT, inotropic support and acidosis. Xe during HT cleared lactate faster; 3 h post-HI median (IQR) values of (Xe HT) 2.8 mmol/L (0.9, 3.1) vs. (HT) 5.9 mmol/L (2.5, 7.9), p = 0.0004.

Conclusion

Xe maintained stable blood pressure, thereby reducing the inotropic support requirements during and after administration independently of induced HT—current neonatal encephalopathy treatment. Xe may offer haemodynamic benefits in clinical neuroprotection studies.

Keywords

XenonHypotensionInotropeInduced hypothermiaHypoxic ischaemiaPig

Copyright information

© Copyright jointly held by Springer and ESICM 2011

Authors and Affiliations

  • Elavazhagan Chakkarapani
    • 1
  • Marianne Thoresen
    • 1
    • 3
  • Xun Liu
    • 1
  • Lars Walloe
    • 3
  • John Dingley
    • 2
  1. 1.Department of Child Health, School of Clinical Sciences, St Michael’s Hospital, Level DUniversity of BristolBristolUK
  2. 2.Swansea Medical SchoolSwansea UniversitySwanseaUK
  3. 3.Department of Physiology, Institute of Basic Medical SciencesUniversity of OsloOsloNorway