Short title: Kinesthetic stimulation in preterm infants
Reviewer(s): Henderson-Smart DJ, Osborn DA
Date of most recent amendment: 19/08/1997
Date of most recent substantive amendment: 18/08/1997
Date next stage expected: / /
Contact
Prof David Henderson-Smart
Director
NSW Centre for Perinatal Health Services Research
Queen Elizabeth Research Institute
University of Sydney
Building DO2
Sydney
NSW AUSTRALIA
2006
Telephone1: +61 2 93517738
Telephone2: +61 2 95158760
Facsimile: +61 2 93517742
E-mail: dhs@extro.ucc.su.oz.au
Sources of support for the review
Royal Prince Alfred Hospital, Sydney
NSW Centre for Perinatal Health Services Research, Sydney
Acknowledgements
Thanks to Annaliese Korner and Rosamond Jones who provided
methodological information and raw data from their trials, and
to Dr. Saroj Saigal who provided further details on concealment
of randomization.
Conflict of interest
None
In preterm infants at risk for apnea, does prophylactic use of kinesthetic stimulation lead to a clinically important reduction in apnea and bradycardia, use of IPPV or neurodevelopmental disability.
The standard search strategy of the Neonatal Review Group was used. This included searches of the Oxford Database of Perinatal trials, Cochrane Controlled Trials Register, Medline, previous reviews including cross references, abstracts, conferences and symposia proceedings, expert informants, journal handsearching mainly in the English language.
All trials in preterm infants at risk of developing clinical apnea which utilized random or quasi-random allocation to treatment with an oscillating mattress or control, were eligible.
Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used with separate evaluation of trial quality and data extraction by each author and synthesis of the data using relative risk.
There were no differences in short term effects (apnea /bradycardia, IVH, use of IPPV, sleep/wake cycles and neurological status at discharge) or longterm effects (in one trial - growth and development to one year).
Implications for practice. Prophylactic use of kinesthetic stimulation cannot be recommended to reduce apnea/bradycardia in preterm infants.
Implications for research. There are currently no clear research questions regarding prophylactic use of kinesthetic stimulation to prevent apnea in preterm infants.
Physical stimulation by nursing staff is commonly used to arouse the apneic infant and so stimulate breathing. This raises the question of whether frequent physical stimuli might reduce the number of apneic events. Furthermore, some believe that the preterm infant is deprived of the frequent stimuli that would be felt in utero and that substituting these with an oscillating mattress to provide kinesthetic stimulation might improve growth and development.
Apnea in infants has been defined as a pause in breathing of greater than 20 seconds, or one of less than 20 seconds and associated with bradycardia and/or cyanosis (Nelson 1978). Recurrent episodes of apnea are common in preterm infants and the incidence and severity increases at lower gestational ages. Although apnea can occur spontaneously and be attributed to prematurity alone, it can also be provoked or made more severe if there is some additional insult such as infection, hypoxemia or intracranial pathology (Henderson-Smart 1995).
If prolonged, apnea can lead to hypoxemia and reflex bradycardia which may require active resuscitative efforts to reverse. There are clinical concerns that these episodes might be harmful to the developing brain or cause dysfunction of the gut or other organs, although there are no data to support this. Frequent episodes may be accompanied by respiratory failure of sufficient severity as to lead to intubation and the use of intermittent positive pressure ventilation (IPPV).
Main question: in preterm infants, does the use of kinesthetic stimulation prevent clinically important apnea and bradycardia, use of IPPV and neurodevelopmental disability.
All trials utilizing random or quasi-random patient allocation, in which treatment was compared with placebo or no treatment were eligible. Measures of the severity of apnea/bradycardia must have been consistent with an evaluation of 'clinical apnea', as defined by the American Academy of Pediatrics (see above).
Preterm or low birth weight infants at risk of developing recurrent apnea/bradycardia.
Kinesthetic stimulation (various forms of oscillating mattresses) used as prophylaxis for recurrent apnea.
1) Apnea/bradycardia; 2) Use of IPPV; 3) Rate of intraventricular haemorrhage; 4) Neuro-developmental status at follow-up.
The standard search strategy of the Neonatal Review Group was used. This included searches of the Oxford Database of Perinatal trials, Cochrane Controlled Trials Register, Medline, previous reviews including cross references, abstracts, conferences and symposia proceedings, expert informants, journal handsearching mainly in the English language.
Standard methods of the Cochrane Collaboration and its Neonatal Review Group were used. The methodological quality of each trial was reviewed by the second author blinded to trial authors and institution(s). Additional information was obtained from authors to clarify methodology and to allow reanalysis of the raw data (Korner 1975, Jones 1981).
Each author extracted the data separately, then compared and resolved differences.
The standard method of Neonatal Review Group was used to synthesize the data using relative risk.
Details of each study (Korner 1975; Jones 1981; Saigal 1986) have been entered into to the included studies table. Each trial used a different form of kinesthetic stimulation. Korner 1975 examined the effect of an irregularly oscillating water bed (16/min); Jones 1981 examined the effect of a regularly oscillating water bed (12-14/min); and Saigal 1986 examined the effect of a regularly oscillating air bed (14-16 /min).
Apnoea/bradycardia events were recorded by the nursing staff (monitor alarms due to episodes of heart rate<100 and/or breathing frequency <20) in the study by Korner et al: by both nursing observations (monitor alarms due to episodes of heart rate <100 and/or apnoea >15 second duration) and blindly assessed polygraphic recordings in the study by Saigal et al; and by blindly assessed polygraphic recordings (bradycardia to 80 or less) in Jones's study.
Saigal 1986 employed the most precise methodology with clear predetermined clinically relevant end points; power calculations and follow-up data were reported. Jones 1981 set out to examine apnea of prematurity using a randomized cross over design and additional data were provided from the author's MD Thesis.
The study by Korner 1975 was primarily concerned with examining the neurologic and behavioral maturation of the premature infant so there was no predetermined end point for apnea. A students T-Test had been used in the original paper, but the data were significantly skewed, especially for the control group. The raw data were kindly provided by the author of the latter trial that allowed calculation of dicotomous outcomes as for the other trials.
Details of the methodological quality of each trial are given in the included studies table.
The methods used for randomization were unclear in two studies (Korner 1975 and Jones 1981).
Due to the nature of the treatment, this could not be blinded in any of the studies.
Two infants were excluded after randomization in the Korner 1975 trial and Jones 1981 randomized three infants with clinical apnea (each acting as their own control) which are not analyzed here. In Saigal 1986, five infants were randomized but not included in the trial because there was no parental consent; all other treated and control infants were analyzed for neonatal outcomes and 75 and 76% in each group respectively were seen in follow up at one year.
The primary outcomes of apnea/bradycardia were assessed blindly in Saigal 1986 and Jones 1981 but not in Korner 1975. All the post treatment assessments in Saigal 1986 were carried out blind.
Using categorical data on apnea/bradycardic episodes, neither the individual studies nor the meta-analysis showed a difference in the number of infants with more than four or more than 10 episodes per 24 hours at any time. There was no difference in the use of mechanical ventilation in the two groups.
Saigal 1986 also examined the prevalence of intraventricular haemorrhage (IVH) and found no difference between groups. Additional prescribed comparisons were made between the treatment and control groups in this study. These included weight and energy intake at various stages in the study, sleep state distribution on and after treatment, Albert Einstein Neurobehavioral Assessment Scale scores at term age, cardiovascular habituation to sound at three months past term age, and Bayley Scales of Infant Development at six and 12 months after term age. None were found to be different.
These trials do not indicate that prophylactic kinesthetic stimulation is of benefit to preterm infants in the prevention of recurrent apnea and bradycardia.
Only Saigal 1986 evaluated possible adverse effects such as disturbances in sleep/wake rhythms with kinesthetic stimulation and found none.
A limitation of this meta-analysis is the combination of the results of trials that used different forms of kinesthetic stimulation, different measures of apnea/bradycardia and had relatively small numbers of subjects.
A lack of effect of prophylactic kinesthetic stimulation in preterm infants at risk of apnea does not preclude a possible benefit of kinesthetic stimulation in the treatment of infants with established apnea of prematurity. This will be the subject of a separate review.
Prophylactic use of kinesthetic stimulation cannot be recommended to reduce apnea/bradycardia in preterm infants.
There are currently no clear research questions regarding prophylactic use of kinesthetic stimulation to prevent apnea in preterm infants.
Study: Jones 1981
Methods: Method of randomization unclear, treatment not
blinded, all infants assessed, outcome (apnea/bradycardia) blindly
assessed.
Participants: Preterm infants (n=11, acted as own controls)
< 33 weeks gestation with < 3 apnea/bradycardias /day, not
on treatment. Three additional infants with apnea on theophylline
also randomized but not analyzed here.
Interventions: Regularly oscillating water bed (12 - 14
cycles/min). Cross over design with 4 hr control period on same
mattress without oscillations.
Outcomes: Bradycardias to 80/min or less (also measured
apneas >9 sec and bradycardias to 60 or less - not analyzed
here).
Notes: Additional methodological information and data were
obtained from author's MD thesis.
Study: Korner 1975
Methods: Method of randomization unclear, no blinding of
treatment, 2 infants excluded (sepsis, meningitis), outcome assessment
not blinded.
Participants: Preterm infants (n=21) 27 -34 weeks gestation
(mean 32 for case and 31 for control), no severe RDS, not small
for gestational age and no congenital abnormalities.
Interventions: Irregularly oscillating water bed (14 cycles/min)
compared with standard mattress.
Outcomes: All apnea / bradycardia (< 100 bpm) episodes
over days 5 - 9 after birth, regardless of severity.
Notes: Additional information on methodology and the raw
data sheets were provided by the author.
Study: Saigal 1986
Methods: Adequate concealment at randomization (sealed,
opaque envelopes); treatment not blinded, all but 5 infants assessed
for apnea/bradycardia and other neonatal outcomes, 76% for neurodevelopment;
assessment of apnea/bradycardia and sleep behavior after treatment,
blinded.
Participants: Preterm infants (n=122) 750 - 1250 gms birthweight,
less than 5 days of age. Infants with grades 3 or 4 IVH or congenital
abnormalities were excluded.
Interventions: Regularly oscillating air mattress (14 -
16 cycles / min) compared with standard mattress.
Outcomes: Apnea >14 sec, bradycardia <100 bpm, (polygraph
recordings), IVH after enrollment, Polygraph of infant sleep and
behavior before and 24 hrs after treatment, Albert Einstein Neonatal
Neurobehavioral Scale at term equivalent age, Bayles Scales of
Infant Development and growth at 6 and 12 months (all post treatment
assessments performed blind).
Jones RAK Recurrent apnoea in preterm infants. MD Thesis, University of London, 1981.
Jones RAK. A controlled trial of a regularly cycled oscillating waterbed and a non-oscillating waterbed in the prevention of apnoea in the preterm infant. Arch Dis Child 1981;56:889-891.
Korner AF, Kraemer HC, Haffner ME, Cosper LM. Effects of waterbed flotation on premature infants: a pilot study. Pediatrics 1975;56:361-367.
Saigal S, Watts JL, Campbell D. No immediate or long-term benefits with the use of an oscillating air mattress (OAM) in preterm infants: a randomized clinical trial. Pediatr Res 1986;20:384.
Saigal S, Watts JL, Campbell D. Randomized clinical trial of an oscillating air mattress in preterm infants: effect on apnea, growth, and development. J Pediatr 1986;109:857-864.
Watts JL, Saigal S, Campbell D. Randomized controlled trial of the prevention of apnea of prematurity by oscillating air mattress. Pediatr Res 1984;18:354.
Henderson-Smart DJ. Recurrent apnoea. In: Bailliere's Clinical Paediatrics. Vol 3 No. 1 Pulmonary Problems in the Perinatal Period and their Sequelae. Ed Yu VYH, Bailliere Tindall, London, 1995 pp 203-222.
Nelson NM. Members of the task force on prolonged apnea of the America Academy of Pediatrics. Pediatrics 1978;61:651-652.
01.00.00 Kinesthetic stimulation vs control
01.01.00 Apnea/bradycardia > 4/day
01.02.00 Apnea/bradycardia > 10/day
01.03.00 Use of IPPV
01.04.00 IVH grade 3 or 4
01.05.00 Neurological abnormality at 1 yr
01.06.00 Mental Development Index at 1 yr
01.07.00 Psychomotor Development Index at 1 yr