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Understanding kangaroo care and its benefits to preterm infants

Authors Campbell-Yeo M, Disher T, Benoit B, Johnston C

Received 26 July 2014

Accepted for publication 18 December 2014

Published 18 March 2015 Volume 2015:6 Pages 15—32

DOI https://doi.org/10.2147/PHMT.S51869

Checked for plagiarism Yes

Review by Single-blind

Peer reviewer comments 4

Editor who approved publication: Professor Laurens Holmes, Jr

Marsha L Campbell-Yeo,1–4 Timothy C Disher,1 Britney L Benoit,1 C Celeste Johnston,2,4,5

1School of Nursing, Dalhousie University, 2Department of Pediatrics, IWK Health Centre, 3Department of Psychology and Neuroscience, Dalhousie University, 4Centre for Pediatric Pain Research, IWK Health Centre, Halifax, NS, 5Ingram School of Nursing, McGill University, Montréal, QC, Canada

Abstract: The holding of an infant with ventral skin-to-skin contact typically in an upright position with the swaddled infant on the chest of the parent, is commonly referred to as kangaroo care (KC), due to its simulation of marsupial care. It is recommended that KC, as a feasible, natural, and cost-effective intervention, should be standard of care in the delivery of quality health care for all infants, regardless of geographic location or economic status. Numerous benefits of its use have been reported related to mortality, physiological (thermoregulation, cardiorespiratory stability), behavioral (sleep, breastfeeding duration, and degree of exclusivity) domains, as an effective therapy to relieve procedural pain, and improved neurodevelopment. Yet despite these recommendations and a lack of negative research findings, adoption of KC as a routine clinical practice remains variable and underutilized. Furthermore, uncertainty remains as to whether continuous KC should be recommended in all settings or if there is a critical period of initiation, dose, or duration that is optimal. This review synthesizes current knowledge about the benefits of KC for infants born preterm, highlighting differences and similarities across low and higher resource countries and in a non-pain and pain context. Additionally, implementation considerations and unanswered questions for future research are addressed.

Keywords: kangaroo care, skin-to-skin contact, infant, preterm, review

Introduction

Mothers hold babies to their chest instinctively. Currently, in less well developed societies, where cribs, strollers, and infant seats are not common, mothers or other caregivers carry their infants on their chest for many hours a day.1 Often there is nothing between the caregiver’s chest and the baby’s skin other than a diaper. This paradigm of holding an infant with ventral skin-to-skin contact (SSC), typically in an upright position and with the swaddled infant on the chest of the parent, is also commonly referred to as kangaroo care (KC), due to its simulation of marsupial care. While there are no recordings of infant care from the distant past, it is likely that KC of newborns has been practiced for eons. An example of the basic survival value of skin-to skin contact between infant and mother can be demonstrated when there is no interference from health care providers at delivery, specifically when the infant is placed skin-to-skin on its mothers chest at birth, within 20 minutes it will work its way toward the nipple and suckle.2

The medical use of this natural phenomenon was originally introduced by Edgar Rey Sanabria in Columbia in 1978 as a strategy to replace the function of incubators, which were in short supply in that country. Infants who were preterm, but otherwise stable, were put in continuous KC with their mothers. There are variations in KC practices, but all of it involves SSC. For example, kangaroo mother care (KMC) refers to SSC that is provided continuously until the infant begins to sweat and resist the position, an indication of more mature temperature regulation and development. Breastfeeding is exclusive, and discharge home occurs earlier than usual, when the baby is stable and the mother is comfortable providing continuous SSC.35 Fathers and other family members can also be providers when the mother is unavailable.6

In resource-rich countries, SSC is seen as complementary to incubator care, and so continuous KC is rare. Implementation of SSC in hospitals has largely been motivated by a desire to humanize what has become a medical experience, and as partial fulfillment of the requirements set out in the Baby Friendly Hospital Initiative (BFHI).7 The purpose of SSC in resource-rich countries has therefore been focused on facilitating infant transition to extrauterine life, promoting early bonding and establishing exclusive breastfeeding. SSC has shown added benefit for the mother, including reduced incidence of post-partum hemorrhage;8 however, this review focuses primarily on the benefits to infants. More recently, strong evidence related to the pain-relieving benefits of SSC, almost exclusively studied in developed countries, has emerged.

KC has been studied for its effect on mortality, morbidity, physiological stability, breastfeeding, parental bonding, development, and pain control.911 Yet despite consistent positive findings for all outcomes, adoption of KC as a routine clinical practice remains extremely variable across settings. It is recommended that KC is a feasible, natural, and cost-effective intervention, and should be standard of care in the delivery of quality health care for all infants, regardless of geographic location or economic status. What remains uncertain is whether continuous KC should be recommended in all settings or if there is a critical period of initiation, dose, or duration that is optimal. This review provides a synthesis of our current knowledge about the benefits of KC, highlighting differences and similarities across gestational age, low and higher resource countries, and in a non-pain and pain context. Additionally, implementation considerations and unanswered questions for future research are addressed.

Benefits of KC

Since the inception of KC as a low-cost alternative to incubator care in areas with limited resources, clinicians and researchers have, over time, documented both physiologic and behavioral benefits for infant and mother (see Table 1). Many of these benefits have been researched sufficiently to permit meta-analysis, such that two Cochrane reviews exist on the subject.9,10 One focuses on healthy term or late-preterm newborns,9 while the second includes low birth weight infants.10

Table 1 Benefits of KC in non-pain context
Notes: aStability of the Cardio-Respiratory system In Premature infants. Composite tool that indicates physiologic stability; bHome Observation for Measurement of the Environment,assesses quality and extent of stimulation available to a child in the home environment.
Abbreviations: LBW, low birth weight; NICU, neonatal intensive care unit; RCT, randomized controlled trial; KC, kangaroo care; MD, mean difference; V, vaginal; C/S, cesarean section; GA, gestational age; RR, relative risk; CI, confidence interval; HR, heart rate; hx, history; REM, rapid eye movement; EEG, electroencephalography; BF, breast feeding; BKC, birth kangaroo care; OR, odds ratio; N/A, not available; MEP, motor evoked potentials; PMA, postmenstrual age; SC, standard care; CG, control group; EBF, exclusive breastfeeding .

Physiologic benefits

Homeostasis (temperature regulation, physiological stability, blood glucose)

When compared with standard care (incubator, radiant warmer, or open crib), KC has shown benefits for homeostasis. Preterm infants who receive KC are more likely to maintain a healthy body temperature, and show increased cardiorespiratory stability.10,1220 Looking at the entire hospitalization, KC is associated with decreased likelihood of infection, severe illness, and death.10,21 Additional evidence for the positive influence of KC exposure on autonomic regulation comes from a recent longitudinal study,22 which showed a significant increase in baseline autonomic stability at 10 years follow-up. Even a very small amount of KC (1 hour a day for 14 days) provided to preterm infants compared with infants cared for only in an incubator was associated with improved infant and maternal outcomes. These findings are of particular interest because they are the first to demonstrate the long-lasting value of early KC.

Implications for practice

The evidence for the ability of KC to promote homeostasis is strong, especially in developing countries, where good evidence suggests that continuous KC can reduce mortality.10 Unfortunately, the clinical picture is less clear in the developed world. The best evidence available is focused on intermittent use of KC, and while homeostatic benefits should theoretically persist when KC is continuous, there is a lack of studies designed to address this. Combined analysis conducted by Conde-Agudelo et al found that benefits that were clear in less developed countries (eg, reduction in sepsis, mortality, and severe illness) were not present when studies were limited to those in developed countries.10 There remain limitations in making conclusions regarding the optimal time spent in KC to achieve maximum benefits. Feldman et al22 offer compelling evidence that an average of 1 hour a day of KC may impart long-lasting benefits, but evidence is still lacking as to whether shorter or longer time periods may impart different benefits. Clinicians should use best judgment in balancing the illness acuity of individual infants, parent availability, and potential benefits.

Implications for research

Benefits that were discovered through research in developing countries should not be extrapolated to better resourced countries. There remains a paucity of studies investigating the effect of KC on mortality, infection, and serious illness in resource-rich countries. Methodologically rigorous studies are needed to understand how to maximize the clinical benefits of KC in hospital environments where advanced support is readily available. Many of the questions that remain are most appropriately answered by randomized controlled trials. In both developed and developing countries, our understanding of the physiological benefits of KC would benefit from routine use of composite physiological measures from which investigators can interpret a more meaningful clinical picture. In a review of the benefits of KC in term children, Moore suggests the use of SCRIP scores, (eg, stability of the cardiorespiratory system as the primary physiological outcome).9 This would help draw conclusions that more broadly address stability as opposed to attempting to interpret outcomes separately.

There is little evidence from which to determine minimum times for KC to maximize physiological benefits, which are of particular interest to clinicians in countries like Canada and the United States of America (USA) where parent availability is often limited. Continuous KC potentially represents a free alternative to expensive equipment, but the price may be high for parents who bear the burden of additional costs associated with being available in neonatal intensive care units. A recent systematic review and meta-analysis28 of 29 papers addressing parental experiences during KC, including 401 mothers and 94 fathers, revealed two overarching themes, ie, a beneficial and restoring effect on both themselves and their child(ren), but also an increased burden, which was a draining experience. Improving our understanding of the optimum daily duration of KC will be important in order to ensure that we do not unjustifiably transfer burden from the health care system to parents.

Late-preterm infants, primarily delivered in developed countries, who are deemed healthy enough to remain on the post partum ward, have been excluded from much of the current literature.9 If physiological stability can be improved by introduction of early and sustained KC interventions for this population, there is potential for considerable impact on health care costs, family burden, and reduction of interventions. Similarly, there is a lack of analysis of benefits for infants born via cesarean section. In the studies included in this review, none considered analysis of outcomes in cesarean deliveries separately. This lack of evidence was one of the issues highlighted in a recent Cochrane review of vaginal versus cesarean birth for preterm infants.29 While results of that meta-analysis found no difference in any of the reported outcomes (respiratory distress, Apgar scores, mechanical ventilation, supplemental oxygen), investigators were only able to include four trials, the most recent published in 1996.

For preterm or low birth weight infants, there is a need for more research examining the effectiveness of continuous early KC for both nonstabilized and relatively stabilized infants.10 Perhaps unstable infants would benefit differentially from KC when compared with stable infants. Moreover, it remains unclear whether physiological benefits are variable depending on the KC provider, because there is so little research comparing mothers and alternative providers, such as fathers, grandparents, or trained volunteers.22

Growth, neurodevelopment, and neurosensory impairment

Perhaps one of the most interesting benefits of KC is the effect on sleep, neurodevelopment, and growth. A recent study by Feldman et al22 provides compelling evidence in this domain as well as in the physiological domain. They found that infants who received an average of 1 hour of KC for 14 days showed a more organized sleep–wake cycle at 10 years of age. Short-term benefits of KC on sleep patterns in preterm infants have been well established and include an increase in quiet sleep, longer cycles, and increased respiratory regularity.15,30,31

As a consequence of the tremendous rate of neurodevelopment that occurs in utero, it is no surprise that preterm infants often suffer neurophysiological sequelae.32,33 Two recent cohort studies used electroencephalographic complexity to measure differences in neurological maturity between preterm infants who received KC and those who did not. While sample sizes were small, the investigators were able to identify a relationship between KC and increased electroencephalographic complexity.34 Additionally, the results showed an increase in primary motor cortex synchronization in response to transcranial magnetic stimulation in the group of infants that received KC.35 These results suggest that KC plays a role in supporting neurodevelopment, which is consistent with earlier findings.31

A recent clinical trial in an Indian hospital compared sustained KC with conventional care in preterm infants. The infants were enrolled in groups of five, with the smallest three infants in each group being assigned to the KC condition.36 Growth at a corrected gestational age of 40 weeks was similar between the intervention group and the control group, but infants receiving KC achieved more rapid physical growth after this point. Evidence for an association between KC and augmented growth comes from the meta-analysis by Conde-Agudelo et al, which found benefits for both continuous and intermittent KC.10 When KC was continuous (KC) it was associated with an increase in weight gain, length, and head circumference.

Clinical implications

Current evidence suggests that KC improves sleep, neurodevelopment, and growth, and should therefore be encouraged in clinical practice. While there is a lack of guidance regarding the optimal duration, the compelling outcomes described by Feldman et al were the result of just 14 days of sessions lasting an average of 1 hour.20 Given the lack of uptake of any variation of KC in some practice settings, it would be reasonable to recommend that all infants should have KC initiated as soon as possible after birth and receive at least this minimal dose daily.

Research implications

The potential for KC to impact neurodevelopment and growth in preterm infants is exciting, but there is still much left to be understood. Dose-response studies would be particularly interesting because they would help families and clinicians to collaborate in order to achieve the best outcomes for the least cost. Studies should be randomized when possible in order to help control for unknown confounding variables.

Investigators should take advantage of the diverse range of instruments available to them in order to learn more about the neurodevelopment changes associated with KC. For example, is the hypothesis that KC increases the rate of neurodevelopment supported by brain imaging? Are the benefits exclusive to pathways related to attention and sleep regulation, or do preterm infants who receive KC have more rapid peripheral neurodevelopment as well?

Studies designed to elucidate the mechanisms via which KC imparts its benefits are lacking. Sleep, neurodevelopment, weight, and length are clinically relevant outcomes but we also need studies designed to tease out how KC interacts with these.

Behavioral benefits

Breastfeeding rates

The BFHI, devised by the World Health Organization, is an international set of guidelines to promote, protect, and support breastfeeding.7 Provision of KC is one of the “ten steps to successful breastfeeding” outlined in the BFHI. Although initially developed for healthy term infants, an international group of experts has made recommendations for adapting the “ten steps” of the BFHI to be applicable to ill and premature infants in neonatal settings.37 In the modified BFHI for neonatal units proposed by Nyqvist et al,37 provision of early, continuous, and prolonged KC without unjustified restrictions is cited as crucial to improving breastfeeding outcomes in this vulnerable infant population.

Evidence supports the influence of KC in increasing maternal milk volume and promoting breastfeeding exclusivity and duration in preterm infants.3840 Flacking et al41 used a prospective longitudinal design to examine the influence of KC on breastfeeding in two age groups: those born very preterm (less than 32 weeks’ gestational age) and preterm (32–36 weeks’ gestational age). They found that in very preterm infants, those who were breastfeeding at 1, 2, 5, and 6 months post discharge has significantly more KC time in hospital. In randomized controlled trials comparing KC interventions with standard care, preterm infants demonstrate initiation of earlier breastfeeding,10 higher breastfeeding exclusivity,10,42 and a longer duration of breastfeeding10,43,44 when compared with infants who are cared for in an incubator or are wrapped in blankets when held by their mothers.

Clinical implications

Based on consistent evidence for KC in promoting breastfeeding, clinicians should encourage KC for preterm infants both in the neonatal intensive care unit and following hospital discharge.5,6 Given the variability in duration of KC provided across studies, there is no consensus regarding the length of time required to optimize the benefit for breastfeeding outcomes. Therefore, it is recommended that mothers be informed of the benefits of KC for breastfeeding, and that they are encouraged and supported in providing KC as early as possible (ideally from birth) and for as long and as often as they would like.31

Limitations and implications for future research

A limitation in the research examining KC and breastfeeding is the reliance on maternal self-report. Given the potential for bias in reporting breastfeeding outcomes due to the social desirability of exclusive breastfeeding, it is important to interpret the findings with caution. While some researchers44 have considered and controlled for baseline maternal intentions to breastfeed, this is not consistently done. Given the significant influence of prenatal intentions to breastfeed in predicting long-term breastfeeding outcomes,45 this is an important variable to measure and report in future studies. While Flacking et al41 found that KC had the greatest benefit for very preterm infants (born at less than 32 weeks’ gestational age), research in this young age group is limited. Future studies examining the relationship between KC and breastfeeding initiation, duration, and exclusivity in infants born at a gestational age of less than 32 weeks is needed. There was variability in measures of exclusivity of breastfeeding, length of KC intervention time in clinical trials, follow-up time points, and control interventions used (eg, incubator care, being wrapped in blankets when held) across the literature. Possibilities of both overestimation and underestimation of the effect of KC on breastfeeding stem from issues such as the treatment of breastfeeding as a dichotomous variable, failure to capture information such as nipple protractility, and “standard care” conditions that include breastfeeding counseling expertise which may not accurately reflect the day to day reality of the unit.9 Consistency in interventions and outcomes is necessary to strengthen future research.

Parent–infant attachment

Attachment is defined as the emotional connection that is formed between infants and caregivers, and it is relevant for clinicians to consider this in infants of all gestational ages, especially in those born preterm.46 Infant-maternal relationships have been shown to be less positive in infants born preterm, and evidence suggests that poor attachment can contribute to more negative outcomes.46,47

Charpak et al48 found that mothers in a KC group scored more favorably on sense of competence, feelings of worry or stress, sensitivity, and infant responsiveness. Total attachment scores determined through structured interviews by Gathwala et al47 were higher in the KC group than in controls. An improved relationship with the infant was supported by higher scores in an investigation by Roberts et al,49 and KC mother–infant pairs showed more symmetrical and less asymmetrical coregulation in a recent study that used the still-face paradigm tool as one of their outcomes.50 Feldman et al22 provided additional evidence supporting the relationship between KC and increased attachment behaviors across the post partum period in addition to greater mother–child reciprocity at 10 years. In one study excluded for using a crossover design, the investigators found no differences between KC and standard care at 4 or 12 months of age in measurement of infant interaction.51

Clinical implications

A significant barrier to the provision of KC is the lack of facilities available for parents to stay (ie, sleep and cooking) near the infant to promote prolonged KC. This is a significant issue in both poorly resourced and resourced areas, although the trend toward single room versus open bay neonatal units and KC centers may lessen this concern and should be supported.52

Research implications

A consistent approach to the measurement of parent–infant attachment would be of benefit because measures vary and make interpretation more difficult. The current evidence suggests that KC promotes greater parent–infant attachment, and the implications of this benefit should cause investigators to consider the inclusion of measures for attachment. Due to the potential neurodevelopment consequences of poor parent–infant attachment, increased information combined with longitudinal designs may help understand the basis of the seemingly neuroprotective effects of KC. More positive attachment may also partially explain some of the observed benefits to breastfeeding initiation and duration. There remains a knowledge gap with regard whether the same benefits in relationships that are observed between mother–infant dyads as a result of KC are also observed between father–infant20 dyads.

KC in the context of pain

Given the benefits of improved physiological stability, and enhanced sleep and regulation, investigation of KC to diminish newborn procedural pain has become a rapidly growing field of study (see Table 2). The role of KC in this context was first examined in full-term infants in 2000 by Gray et al.53 Three years later, Johnston et al examined its effectiveness in preterm infants at a gestational age of 32 to 36 weeks at birth.54 Both studies reported a significant lowering of behavioral pain responses, and numerous other studies followed with similar results favoring KC. A recent Cochrane review included 19 randomized trials (n=1,594 infants, with 765 being term infants5467) and used physiological, behavioral, and composite measures as the primary outcomes.11 The majority of the studies5359,6470 (n=1,219) compared KC with standard care or no treatment, and used heel lance as the painful procedure.53,54,5667,71

Table 2 Benefits of kangaroo care in pain context
Abbreviations: EBM, expressed breast milk; GA, gestational age; KC, kangaroo care; CI, confidence interval; MD, mean difference; HR, heart rate; HRV, heart rate variability; SpO2, oxygen saturation; PIPP, premature infant pain profile; RCT, randomized controlled trial; LBW, low birth weight; NICU, neonatal intensive care unit; V, vaginal; C/S cesarean section; SC, standard care.

Kangaroo care compared with incubator control

Physiological parameters

Physiological indicators reported were heart rate response, heart rate recovery, heart rate variability, oxygen saturation during the painful procedure, oxygen saturation after the painful procedure, and change in oxygen saturation. Twelve studies examined heart rate or heart rate variability during and/or heart rate recovery following a heel lance procedure.53,54,5658,60,64,66,67,6971 All studies favored KC or found no difference, but only a few studies could be combined in meta-analysis. Oxygen saturation during and/or following the painful procedure, reported by four studies,64,66,69,70 was unable to be combined. Although two of the studies64,70 reported that average oxygen saturation was higher in the KC group during the painful procedure, only Sajedi et al70 showed these differences to be significant. Of two studies reporting change in oxygen saturation, neither found a difference between KC and standard care.60,67

Validated pain assessment tools

Validated pain scores, including the Premature Infant Pain Profile (PIPP),54,55,59,60,64 Neonatal Facial Coding System,56,68 and Neonatal Infant Pain Scale6870 were measured in ten studies. Pain scores regardless of the tool used appeared to favor KC with lower Neonatal Facial Coding System scores during procedure, with a mean difference of 1.872 in favor of KC (P<0.001) in Castral et al.56 Both Sajedi et al70 and Saeidi et al69 reported Neonatal Infant Pain Scale scores that significantly favored KC. Five studies used the PIPP as the outcome for heel lance.54,55,59,60,64 Based on the combined analysis of four studies,54,59,60,64 there was a significant effect post heel lance in favor of KC at 30 seconds, at 60 seconds,54,59,64 and 90 seconds.54,59,64 No significant difference between KC and controls were noted in PIPP scores at 120 seconds.54,59,64 Additional outcomes, including endocrine response, cry duration, infant state, and adverse effects, were measured in a few small studies, with mixed or nonsignificant findings.59

Kangaroo care versus alternative treatments or alternative providers

Comparisons have been made in four studies with sweet taste,60,68 breastfeeding,71 enhanced KC (including the addition of rocking and singing with KC),62 fathers,62 and unrelated females.61 When KC with sweet taste (glucose) was compared with control in preterm neonates undergoing heel lance, heart rate, oxygen saturation variability, and PIPP scores all were reported to significantly favor KC. Similarly, heart rate, oxygen saturation, Neonatal Facial Coding System, and duration of crying were not reported to be different between KC and breastfeeding, but both were better than swaddled control.60 The addition of auditory, vestibular, or gustatory factors with KC (rocking, singing, and offering the infant a finger or pacifier for sucking by the mother providing KC) did not result in any differences when compared with maternal KC alone. Two studies, both using a crossover design, compared the analgesic effect of maternal KC to SSC provided by an alternate caregiver: one with fathers62 and the other with an unrelated woman.61 In both cases, the differences in heart rate recovery and PIPP scores were not significant in spite of the large mean difference in favor of the mother, due mostly to high variance.

Clinical implications

KC is a simple, natural, and cost-effective intervention to effectively diminish behavioral pain response in preterm infants. KC should be routinely offered to all infants undergoing needle-related procedures. Although there is some evidence that combining KC provided by the mother with sweet-tasting solutions may be synergistic, further study is warranted before this combination can be recommended as standard care. In the absence of a mother, a father,62 unrelated woman,61 or a co twin,72,73 may be considered as as there is some evidence that they may be an effective alternate.

Implications for research

Despite strong evidence that KC effectively lowers composite behavioral pain scores for both full-term and preterm infants as young as 28 weeks’ gestational age undergoing a single heel lance or intramuscular injection compared with incubator control, there remain many unanswered questions. Studies examining the sustained effect of KC over repeated procedures, as well as studies with larger sample sizes replicating prior work, including similar outcomes, are required. Moreover, little is known about whether combining KC with other comforting interventions can enhance its benefits for pain relief. It is clinically important for future studies to examine the optimal dose or duration of KC needed to be effective. The range of time for KC prior to the painful procedure was 2 minutes68 to 3 hours.66 The only studies that compared times were two studies by Cong et al.58,59 Although both studies seemed to favor 30 minutes to either longer (80 minutes)58 or shorter doses (15 minutes),59 other studies using different outcomes favored KC for times longer and shorter than 30 minutes, so no conclusion can be made. Investigators should consider reporting findings from the entire sample as well as differentiating among gestational ages when possible. Lastly, examining whether the benefits of KC associated with early pain reduction and immediate pain relief may also lead to improved longer term outcomes are needed.

Considerations for implementation

In spite of the plethora of documented benefits of KC in preterm infants, KC is not consistently practiced in this population. In a national survey of nurse managers in USA Newborn Intensive Care Units (NICUs), Engler et al74 found that while 82% of respondents indicated that KC was implemented in some form on their unit, practice was informed by nurse perceptions as opposed to scientific evidence. It has been consistently demonstrated that both parents and clinicians perceive KC as a positive intervention for mothers and their infants.7579 However, despite generally positive attitudes, inconsistencies may exist in parent and nurse perceptions of optimal KC practices. For example, in a recent prospective cohort study conducted by Hendricks-Munoz et al,80 parents and nurses both reported that KC benefits infants; however, only 18% of nurses compared with 63% of mothers believed that KC should be provided to their infants on a daily basis.

In addition to varying attitudes toward KC, numerous barriers have been identified. A consistently described barrier relates to the safety of facilitating KC in the preterm infant. Specifically, the highly technological equipment used to care for these infants has been identified as limiting opportunities for KC,74,7679,81,82 with several studies reporting inconsistent policies and KC practices in infants who are intubated or have arterial or venous lines in place.74,81 Maternal concern around infant well-being during KC, such as fear that the infant may stop breathing, is another concern that has been reported.77,79 Inadequate staff education and experience in facilitating KC for clinically compromised infants was another barrier identified, as well as lack of staff and time to appropriately support KC in both the NICU74,77,79,81 and following delivery by cesarean section.83 Both parents and health care providers identified the NICU environment as limiting parental visitation and opportunities to provide KC. For example, frequently identified barriers included lack of privacy, space, and comfortable chairs at the bedside, as well as a lack of facilities for meal preparation and parental rooming in.77,78,81,84 Parent-related factors such as maternal pain (eg, breast, back, or incisional pain),77,85 having responsibilities in the home (eg, other children, chores),77,81,85 and limited knowledge of the benefits of KC were additional barriers that were identified to limit the availability and motivation of mothers to provide KC.81

While it is evident that there are numerous barriers to successful implementation of KC, findings also highlight ways in which to facilitate this practice in preterm infants. Educational interventions have been consistently cited as necessary to train staff in the knowledge and skills needed to promote and support KC effectively.74,76,80,81,86 In a recent prospective cohort study examining the impact of a training program on KC perceptions and practice competency, nurses received didactic education and simulation training for assessing and placing infants in KC.80 Nurses’ competency in supporting KC for infants requiring nasal continuous positive airway pressure and mechanical ventilation improved from 30% to 92% (P<0.001) and from 10% to 48% (P<0.004), respectively. In addition, nurses who reported feeling uncomfortable in this competency decreased to 0%, and the perceived value increased from 50% to 100% (P<0.001). Having clear policies in place to guide evidence-informed KC implementation,74,81,86 as well as KC leaders and unit-based champions,81 have also been identified as ways to facilitate ease of use in ill full-term and preterm infants.

In addition to educational interventions for staff, parent education regarding the benefits of KC and how to safely hold their infant in addition to assessing their well-behind has been documented as a way to encourage KC implementation.78,81,83,86,87 Modification of the physical environment by providing privacy screens, comfortable chairs, and family rooms has been identified by parents to support KC.77,78 Finally, assistance in positioning infants in KC, providing parents with information and practical advice, as well as providing reminders and follow-ups around KC practices,77,78,81,87 have been identified by both parents and health care providers as valuable in supporting the implementation of KC.

Conclusion

Kangaroo care is a natural, effective, and low-cost intervention that can be utilized in any setting. There is strong evidence related to its numerous benefits, including physiological, behavioral, and pain-relieving aspects for preterm newborns, both healthy and ill, as well as less stress and improved self-efficacy in parents. Mothers and family members have a unique relationship and are highly invested to ensure that optimal outcomes are achieved for their newborns. Yet their active participation in care often remains underutilized. Despite a few remaining unanswered questions, the use of KC should be considered standard of care for all infants and be initiated early with the ultimate goal to minimize separation of the mother–infant dyad.

More evidence is required in order to recommend implementation of KC in resource-rich environments. Though it is tempting to make this recommendation considering the diverse array of benefits offered, questions remain as to how implementation might affect mortality, infection, and severe illness. There a need for dose-response studies in this population that include a continuous or near-continuous arm, but these should be accompanied by economic measurements that will determine the tangible and intangible costs taken on by parents. To this end, health economists should be considered as potential members of the interdisciplinary team. Additionally, in poorly resourced countries, greater government funding should target the creation of KC centers that incorporate clean water, cooking, and sleeping facilities for mothers to remain exclusively with their infants.

Disclosure

The authors report no conflicts of interest in this work.


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