JOURNAL ARTICLE

Maturation of heart rate and blood pressure variability during sleep in term-born infants

Stephanie R Yiallourou, Scott A Sands, Adrian M Walker, Rosemary S C Horne
Sleep 2012, 35 (2): 177-86
22294807

STUDY OBJECTIVES: Abnormal blood pressure control is implicated in the sudden infant death syndrome (SIDS). However, no data exist on normal development of blood pressure control during infancy. This study assessed maturation of autonomic control of blood pressure and heart rate during sleep within the first 6 months of life.

PARTICIPANTS: Term infants (n = 31) were studied longitudinally at 2-4 weeks, 2-3 months, and 5-6 months postnatal age.

INTERVENTIONS: Infants underwent daytime polysomnography at each age studied. Blood pressure and heart rate were recorded during quiet (QS) and active (AS) sleep in undisturbed baseline and head-up tilt conditions.

MEASUREMENTS AND RESULTS: Autonomic control was assessed using spectral indices of blood pressure and heart rate variability (BPV and HRV) in ranges of low frequency (LF, reflecting sympathetic + parasympathetic activity) and high frequency (HF, parasympathetic activity), total power (LF+HF), and LF/HF ratio (sympathovagal balance). With increasing postnatal age and predominantly during QS, HRV-LF, HRV-HF, and HRV total power increased, while HRV-LF/HF decreased. BPV-LF/HF also decreased with postnatal age. All changes were evident in both baseline and head-up tilt conditions. BPV-LF and BPV total power during tilts were markedly reduced in QS versus AS at each age.

CONCLUSIONS: In sleeping infants, sympathetic vascular modulation of the circulation decreases with age, while parasympathetic control of heart rate is strengthened. These normative data will aid in the early identification of conditions where autonomic function is impaired, such as in SIDS.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read
22294807
×

Save your favorite articles in one place with a free QxMD account.

×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"