Optimal body temperature in transitional extremely low birth weight infants using heart rate and temperature as indicators.
OBJECTIVE
To explore body temperature in relationship to heart rate in extremely low birth weight (ELBW) infants during their first 12 hours to help identify the ideal set point for incubator control of body temperature.


METHODS
Within subject, multiple-case design.


METHODS
A tertiary neonatal intensive care unit (NICU) in North Carolina.


METHODS
Ten infants born at fewer than 29 weeks gestation and weighing 400 to 1,000 g.


METHODS
Heart rate and abdominal body temperature were measured at 1-minute intervals for 12 hours. Heart rates were considered normal if they were between the 25th and 75th percentile for each infant.


RESULTS
Abdominal temperatures were low throughout the 12-hour study period (mean 35.17-36.68 degrees C). Seven of 10 infants had significant correlations between abdominal temperature and heart rate. Heart rates above the 75th percentile were associated with low and high abdominal temperatures; heart rates less than the 25th percentile were associated with very low abdominal temperatures. The extent to which abdominal temperature was abnormally low was related to the extent to which the heart rate trended away from normal in 6 of the 10 infants. Optimal temperature control point that maximized normal heart rate observations for each infant was between 36.8 degrees C and 37 degrees C.


CONCLUSIONS
Hypothermia was associated with abnormal heart rates in transitional ELBW infants. We suggest nurses set incubator servo between 36.8 degrees C and 36.9 degrees C to optimally control body temperature for ELBW infants.
Knobel
Robin B
RB
Duke University School of Nursing, Durham, NC.. Electronic address: robin.knobel@duke.edu.
Holditch-Davis
Diane
D
Marcus E. Hobbs Distinguished Professor of Nursing and associate dean of Research Affairs, Duke University School of Nursing, Durham, NC.
Schwartz
Todd A
TA
Department of biostatistics and the School of Nursing at the University of North Carolina at Chapel Hill, Chapel Hill, NC.
D000005:Abdomen / Q000502:physiology*; D001831:Body Temperature / Q000502:physiology*; D015400:Clinical Nursing Research; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D007035:Hypothermia / Q000175:diagnosis / Q000503:physiopathology* / Q000517:prevention & control; D007186:Incubators, Infant; D052577:Infant, Extremely Low Birth Weight / Q000502:physiology*; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000175:diagnosis / Q000503:physiopathology* / Q000517:prevention & control; D015931:Intensive Care, Neonatal / Q000379:methods; D016014:Linear Models; D008297:Male; D017283:Neonatal Nursing / Q000379:methods; D009657:North Carolina; D009730:Nursing Assessment / Q000379:methods; D017410:Practice Guidelines as Topic; D012016:Reference Values
Pediatrics. 2000 Oct;106(4):659-71
11015506
Pediatrics. 2001 Aug;108(2):395-401
11483805
J Perinatol. 2009 Dec;29(12):814-21
19626030
Arch Dis Child Fetal Neonatal Ed. 1997 Jan;76(1):F47-50
9059187
Arch Dis Child. 1984 Jan;59(1):18-22
6696489
Early Hum Dev. 1983 Oct;8(3-4):351-75
6641579
Pediatrics. 2003 Apr;111(4 Pt 2):e497-503
12671170
Am J Obstet Gynecol. 1991 Jan;164(1 Pt 1):111-2
1986597
Am J Obstet Gynecol. 1987 Sep;157(3):743-8
3631176
Pediatrics. 1991 Sep;88(3):542-6
1881734
J Perinatol. 2005 May;25(5):304-8
15861196
Am J Perinatol. 2009 May;26(5):323-9
19085678
Pediatrics. 1987 Jan;79(1):47-54
3797170
Pediatrics. 2005 Jun;115(6):1501-12
15930210
J Pediatr. 1999 May;134(5):547-51
10228287
Pediatr Res. 1993 Jul;34(1):47-50
8356018
Am Heart J. 1964 Aug;68:183-92
14204313
Pediatrics. 1964 Aug;34:163-70
14211076
Acta Paediatr. 2002;91(5):566-70
12113327
J Clin Endocrinol Metab. 1993 Aug;77(2):382-7
8393883
Indian J Pediatr. 2007 Mar;74(3):249-53
17401263
J Perinat Med. 2000;28(2):104-10
10875094
J Adv Nurs. 2005 Dec;52(5):482-9
16268853
J Paediatr Child Health. 2008 Jun;44(6):325-31
18194198
Biochim Biophys Acta. 2001 Mar 1;1504(1):82-106
11239487
Singapore Med J. 2008 Jul;49(7):556-60
18695864
J Obstet Gynecol Neonatal Nurs. 2007 May-Jun;36(3):280-7
17489935
Pediatr Res. 1985 Jan;19(1):60-3
3969315
Pediatrics. 1964 Aug;34:171-81
14211077
Anaesthesist. 2007 Sep;56(9):907-11
17554514
J Perinatol. 2008 Nov;28(11):754-8
18580878
Childs Nerv Syst. 1990 Aug;6(5):245-8; discussion 248-9
2224873
J Perinatol. 2007 Dec;27 Suppl 2:S45-7
18034181
Anesthesiology. 1968 Mar-Apr;29(2):314-26
5635884
Arch Dis Child. 1991 Jul;66(7 Spec No):783-6
1863124
Early Hum Dev. 2001 Apr;62(1):33-41
11245993
J Perinatol. 2003 Dec;23(8):640-5
14647160
Pediatrics. 2003 Jul;112(1 Pt 1):33-9
12837865
Pediatrics. 1958 Nov;22(5):876-86
13600915
Cochrane Database Syst Rev. 2008 Jan 23;(1):CD004210
18254039
Acta Paediatr Scand. 1979 Nov;68(6):795-801
539401
Am J Perinatol. 2003 May;20(4):181-8
12874728
Adv Neonatal Care. 2002 Jun;2(3):149-60
12903226