AIM: Newborn infants produce significant heart rate responses to both head-up and head-down tilting: heart rate increases with head-up tilting and decreases with head-down tilting. However, previously we found that, at 2-4 mo of age, heart rate increases were no longer significant following slow head-up tilting. This study was designed to determine if 2-4-mo-old infants have significant increases in heart rate when tilted rapidly. METHODS: Fifty-four infants were tested as newborns or at 2-4 mo of age. Heart rate was measured while infants were tilted to a 30 degrees head-up angle either slowly over a period of 30 s or rapidly in 5 s. RESULTS: Newborns exhibited increases in heart rate using both tilt speeds; however, at 2-4 mo of age, heart rate did not change significantly using either speed of tilting. CONCLUSION: There are significant early developmental changes in cardiac responses to hypotensive challenge. Newborns react like adults, mounting sustained increases in heart rate in response to head-up tilting, but at 2-4 mo of age sustained heart rate responses are no longer significant. Tilt tests may provide a standardized method for assessing autonomic competence during the period of maximum vulnerability to sudden infant death syndrome.
AIM: Newborn infants produce significant heart rate responses to both head-up and head-down tilting: heart rate increases with head-up tilting and decreases with head-down tilting. However, previously we found that, at 2-4 mo of age, heart rate increases were no longer significant following slow head-up tilting. This study was designed to determine if 2-4-mo-old infants have significant increases in heart rate when tilted rapidly. METHODS: Fifty-four infants were tested as newborns or at 2-4 mo of age. Heart rate was measured while infants were tilted to a 30 degrees head-up angle either slowly over a period of 30 s or rapidly in 5 s. RESULTS: Newborns exhibited increases in heart rate using both tilt speeds; however, at 2-4 mo of age, heart rate did not change significantly using either speed of tilting. CONCLUSION: There are significant early developmental changes in cardiac responses to hypotensive challenge. Newborns react like adults, mounting sustained increases in heart rate in response to head-up tilting, but at 2-4 mo of age sustained heart rate responses are no longer significant. Tilt tests may provide a standardized method for assessing autonomic competence during the period of maximum vulnerability to sudden infant death syndrome.
Authors: Matthew S Perzanowski; Khalil W Savary; Emilio Arteaga-Solis; Laura A Lautenbacher; Natalie H Brito; Virginia A Rauh; J David Nugent; Amy J Elliott; Michael M Myers; William P Fifer Journal: Am J Respir Crit Care Med Date: 2018-08-15 Impact factor: 21.405
Authors: Hannah C Kinney; George B Richerson; Susan M Dymecki; Robert A Darnall; Eugene E Nattie Journal: Annu Rev Pathol Date: 2009 Impact factor: 23.472
Authors: William P Fifer; Sherri Ten Fingers; Mitzi Youngman; Esperanza Gomez-Gribben; Michael M Myers Journal: Dev Psychobiol Date: 2009-04 Impact factor: 3.038