Pulsed delivery of nitric oxide counteracts hypoxaemia in the anaesthetized horse
2001 (English)In: Veterinary Anaesthesia and Analgesia, ISSN 1467-2987, E-ISSN 1467-2995, Vol. 28, no 1, 3-11 p.Article in journal (Refereed) Published
To study the effect of the pulsed delivery of nitric oxide (NO) on pulmonary gas exchange in the anaesthetized horses.
Prospective, controlled randomized.
Five healthy Standardbred trotters, three geldings and two mares.
The horses were anaesthetized with thiopentone and isoflurane and positioned in dorsal recumbency. Nitric oxide was added as a pulse to the inspired gas during the first half of each inspiration. In three horses the effect of NO on the ventilation–perfusion distribution was also investigated using the multiple inert gas elimination technique. Data were analysed with repeated measures ANOVA.
During spontaneous breathing, arterial oxygen tension (PaO2) increased with NO inhalation, from 14 ± 2 to 29 ± 3 kPa (105 ± 15 to 218 ± 23 mm Hg) (p < 0.001). Arterial oxygen tension also increased, from 17 ± 3 to 31 ± 5 kPa (128 ± 23 to 233 ± 38 mm Hg) (p < 0.05) during intermittent positive pressure ventilation. The increase in PaO2 was mainly due to a reduced right to left vascular shunt, but ventilation and perfusion matching also improved. The beneficial effect of NO inhalation was lost within 5 minutes of its discontinuation.
Delivery of NO as a pulse during inspiration is an effective method for counteracting impaired gas exchange caused by anaesthesia in horses. Pulsation has to be continuous because of the transience of NO's therapeutic effect.
Horses with impaired pulmonary gas exchange during anaesthesia can be treated with pulsed NO inhalation.
Place, publisher, year, edition, pages
2001. Vol. 28, no 1, 3-11 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-54751DOI: 10.1046/j.1467-2987.2000.00035.xOAI: oai:DiVA.org:uu-54751DiVA: diva2:82660