+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Spectral analysis of diaphragmatic EMG during the neonatal biphasic hypoxic ventilatory response

Pediatric Research 21(3): 238-241
Spectral analysis of diaphragmatic EMG during the neonatal biphasic hypoxic ventilatory response
The newborn infant monkey consistently demonstrates a biphasic ventilatory response to hypoxemia. We have previously shown that the ventilatory depression during the late portion of this biphasic response is secondary to a decline in inspiratory volume that cannot be explained solely by central neural depression. We hypothesized that hypoxemia caused the diaphragm to fatigue, thereby accounting for the late ventilatory depression during the biphasic neonatal hypoxic response. Diaphragmatic fatigue has been reported to be associated with a decrease in the centroid frequency (Fc) of the electromyogram derived through frequency spectral analysis. Therefore, we analyzed the power spectral density of the diaphragmatic electromyogram recorded from percutaneously implanted crural diaphragmatic electrodes in five 2-day-old infant monkeys while they breathed room air and after 5 min exposure to two levels of hypoxemia during the late ventilatory depression. A fast Fourier transform of EKG free diaphragmatic electromyogram was used to compute the power spectral density and the Fc. The Fc during room air breathing was statistically equivalent to the Fc observed after five minutes exposure to 12% FiO2 (p = 0.79), and 8% FiO2 (p = 0.74) when ventilation was falling. In conclusion, our data demonstrate that changes in the centroid frequency are not present during the biphasic ventilatory decline that occurs with the hypoxic ventilatory response in newborn monkeys. Thus, diaphragmatic fatigue, as defined by a decline in Fc, does not occur during the neonatal biphasic hypoxic response.

Accession: 006459399

PMID: 3562122

DOI: 10.1203/00006450-198703000-00006

Related references

Spectral analysis of diaphragmatic electromyogram during the neonatal biphasic hypoxid ventilatory response. American Review of Respiratory Disease 133(4 SUPPL): A104, 1986

Diaphragmatic activity during biphasic ventilatory response to hypoxia in rats. Archives of Physiology & Biochemistry 105(3): 305, 1997

Diaphragmatic activity during biphasic ventilatory response to hypoxia in rats. Respiration Physiology. 111(2): 153-162,., 1998

Role of central glutamate acid GABA and substance-P in the biphasic hypoxic ventilatory response in the rat. FASEB Journal 8(4-5): A394, 1994

Long-term effects of neonatal cryoanesthesia on hypoxic ventilatory response in weanling rats depend on neonatal testosterone. Advances in Experimental Medicine and Biology 536: 555-558, 2003

Potentiation of the hypoxic ventilatory response by 1 day of hyperoxia in neonatal rats. Respiratory Physiology & Neurobiology 176(1-2): 50-56, 2011

Effect of prenatal nicotine exposure on biphasic hypoxic ventilatory response and protein kinase C expression in caudal brain stem of developing rats. Journal of Applied Physiology 96(6): 2213-2219, 2004

Hypoxic ventilatory response in Tac1-/- neonatal mice following exposure to opioids. Journal of Applied Physiology 113(11): 1718-1726, 2013

Developmental plasticity of the hypoxic ventilatory response in rats induced by neonatal hypoxia. Journal of Physiology 557(Pt 2): 645-660, 2004

Neonatal maternal separation and sex-specific plasticity of the hypoxic ventilatory response in awake rat. Journal of Physiology 554(Pt 2): 543-557, 2003