Advertisement
Research Article| Volume 64, e154-e158, May 2022

Effects of swaddled and traditional tub bathing on stress and physiological parameters of preterm infants: A randomized clinical trial in China

Open AccessPublished:December 22, 2021DOI:https://doi.org/10.1016/j.pedn.2021.11.028

      Highlights

      • Validated the advantages of swaddled bathing in China's preterm infants.
      • Enriched the experimental data on swaddled bathing in different countries.
      • Recommend that neonatal intensive care units use swaddled bathing.

      Abstract

      Purpose

      The present research aims to study the effects of swaddled and traditional tub bathing on premature infants to identify better ways to bathe.

      Design and methods

      Eligible premature infants (n = 60) were randomly assigned to either swaddled bathing or traditional tub bathing group. Stress scores and physiological indicators were measured 10 min before, immediately after, and 10 min after bathing. Crying times were also recorded for both groups. Data were reported as mean and standard deviation (SD) or frequency (percentage). For analyzing the data, the Student t-test and Chi-square test were employed.

      Results

      Swaddled bathing has less effect on the respiratory rate, heart rate, and oxygen saturation (p < 0.05). Both bathing methods led to a decrease in the temperature of infants. Still, the temperature of infants 10 min after bathing, in the swaddled bathing group was rose higher than the traditional tub bathing (t = 2.813, p < 0.05). The stress score of the swaddled bathing group, immediately after and ten minutes after bathing was lower than the traditional tub bathing group. The crying time of the swaddled bathing group was 32 ± 24.740(s) lower than the traditional tub bathing group 94.43 ± 41.625(s).

      Conclusions

      The advantages of swaddled bathing over traditional tub bathing were validated for feasibility in China's preterm infants. Swaddled bathing is recommended method for bathing technique in the neonatal intensive care unit.

      Practice implications

      Swaddled bathing is beneficial for the development of premature infants, as it results in less noxious stimuli and stress on the developing premature neonates.

      Keywords

      Introduction

      Premature birth results possess significant health problems affecting the global population. Beck et al., analyzed data from 92 countries and reported the estimated global prematurity prevalence at 9.6% in 2005 (
      • Beck S.
      • Wojdyla D.
      • Say L.
      • Pilar Bertran A.
      • Meraldi M.
      • Harris Requejo J.
      • Van Look P.
      The worldwide incidence of preterm birth: A systematic review of maternal mortality and morbidity.
      ). Whereas Blencowe analysis of data from 99 countries that the worldwide prematurity prevalence rate in 2010 was at 11.1%, ranging from about 5% in European countries to 18% in African countries (
      • Blencowe H.
      • Cousens S.
      • Oestergaard M.Z.
      • Chou D.
      • Moller A.B.
      • Narwal R.
      • Lawn J.E.
      National, regional, and worldwide estimates of preterm birth rates in 2010 with time trends since 1990 for selected countries: A systematic analysis and implications.
      ). However, the reported incidence of prematurity may differ from the actual prevalence rate due to the regional differences in the fetal age measurements, definitions of premature infants, and differences in data collection and reporting (
      • Vogel J.P.
      • Chawanpaiboon S.
      • Moller A.B.
      • Watananirun K.
      • Bonet M.
      • Lumbiganon P.
      The global epidemiology of preterm birth.
      ). The incidence of prematurity reported in the Chinese cities was approximately 8.1% in 2005 (
      • Juan L.
      • Wang Q.
      • Hongmin W.
      • Yang Y.
      • Lizhong D.
      • Yao Y.
      • Wei K.
      A survey of neonatal births in maternity departments in urban China in 2005.
      ).
      With the recent development in assisted reproductive technology, the change of Chinese population policy, and the increase in elderly parturient women, premature births in China are increasing every year. Therefore, premature infants, require more care and attention (
      • Küçük A.D.
      • İnal S.
      The effect of individualized developmental care practices in preterm infants.
      ). In addition, premature infants can be exposed to external noxious stimuli for weeks or months, in the neonatal intensive care unit, such as irregular noise and intense light, etc., leading to a higher risk for adverse health outcomes (
      • Cerasani J.
      • Ceroni F.
      • De Cosmi V.
      • Mazzocchi A.
      • Morniroli D.
      • Roggero P.
      • Giannì M.L.
      Human milk feeding and preterm infants’ growth and body composition: A literature review.
      ).
      Bathing is one of the most common skincare methods (cleaning & moisturizing) for newborns and is also essential for the child's early development, prevention of infections, and for promoting the development of epidermis barrier function (
      • Burdall O.
      • Willgress L.
      • Goad N.
      Neonatal skin care: Developments in care to maintain neonatal barrier function and prevention of diaper dermatitis.
      ;
      • Gucev Z.
      Newborn screening in southeastern Europe.
      ). Additionally, bathing enhances comfort and promotes the development of newborn's immune and nervous systems (
      • Lund C.
      Bathing and beyond: Current bathing controversies for newborn infants.
      ). A full-body bath, along with the head and neck, can keep the newborn's temperature stable and prevent cord infections. However, exposure to external stimuli such as light, noise, temperature change (
      • Nechay A.
      • Stephenson J.B.
      Bath-induced paroxysmal disorders in infancy.
      ;
      • Suzuki M.
      • Shimbo T.
      • Ikaga T.
      • Hori S.
      Incidence and characteristics of bath-related accidents.
      ), sleep disruption, separation from the mother (
      • Smith G.C.
      • Gutovich J.
      • Smyser C.
      • Pineda R.
      • Newnham C.
      • Tjoeng T.H.
      • Inder T.
      Neonatal intensive care unit stress is associated with brain development in preterm infants.
      ), increased oxygen consumption associated with increased crying, augmented risk of respiratory distress and unstable vital signs, may contribute adversely to affect the brain and neuroendocrine development (
      • Incorpora G.
      • Pavone P.
      • Cocuzza M.
      • Privitera M.
      • Pavone L.
      • Ruggieri M.
      Neonatal onset of bath-induced alternating hemiplegia of childhood.
      ;
      • Montirosso R.
      • Provenzi L.
      • Fumagalli M.
      • Sirgiovanni I.
      • Giorda R.
      • Pozzoli U.
      • Borgatti R.
      Serotonin transporter gene (SLC6A4) methylation associates with neonatal intensive care unit stay and 3-month-old temperament in preterm infants.
      ;
      • Taşdemir H.O.
      • Efe E.
      The effect of tub bathing and sponge bathing on neonatal comfort and physiological parameters in late preterm infants: A randomized controlled trial.
      ). For premature infants, caregivers must pay attention to physiological changes and stress responses during bathing to take appropriate measures to relieve associated stress (
      • Cooke A.
      • Bedwell C.
      • Campbell M.
      • McGowan L.
      • Ersser S.J.
      • Lavender T.
      Skin care for healthy babies at term: A systematic review of the evidence.
      ).
      Swaddled bathing is a relatively new way for newborns to bath. (
      • Fernández D.
      • Antolín-Rodríguez R.
      Bathing a premature infant in the intensive care unit: A systematic review.
      ). Swaddled bathing can improve comfort and reduce the stress caused by bathing and has been verified in other countries and regions. However, there is no uniform standard available to bath premature infants due to the different research procedures.
      Therefore, the current clinical trial is conducted to improve the procedure of swaddled bathing. This study also compared swaddled bathing with traditional tub bathing by assessing the physiological index and stress induction on premature infants in China.

      Methods

      Study design and setting

      The Institute Ethics Committee approved this study. This prospective randomized clinical trial study was registered in the Clinical Trial. Registry and conducted from 5th May to 30th June 2021. This study was performed with the guidance of the CONSORT 2010 statement.

      Study procedure

      Parents of enrolled infants were informed about the aim, study plan, time, duration of the study, and data collection through the “Participant Consent Form,” and their written consents were obtained. The information such as postnatal age, gender, birth weight, weight at bath time, Apgar score, time from the last feeding, and maternal information including the age of the pregnancy, gestational period, the number of births, week of maternal pregnancy, mode of delivery, and absence of pregnancy-associated morbidities, were collected through the “Participant Information Form”.
      This study was a prospective randomized controlled experimental trial conducted to determine the effect of “traditional tub bathing (TTB)” and “swaddled bathing (SB)” methods on the physiological parameters and stress levels in preterm infants. The studied variables included body temperature, respiratory rate, heart rate, oxygen saturation levels, crying time, and the Newborn stress scale score.
      The two groups were simultaneously assessed for body temperature, respiratory rate, heart rate, oxygen saturation levels, and the crying time using the same thermometer, stopwatch, and oximeter. The stress measurement was analyzed based on the Newborn stress scale (NSS) (
      • Ceylan S.S.
      • Bolışık B.
      Examining psychometric properties of newborn stress scale.
      ), developed in 2017 by Ceylan et al. The scale has been tested for its reliability and validity, including facial expression, color, respiration, activity level, consolation, muscle tone, extremities, and posture. Each parameter was scored on a scale of 0–2. The minimum score was 0, and the maximum score was 16 for this scale, where a higher score represented increased stress levels in premature infants. The advantage of this scale includes an efficient, convenient, and more personalized measure of the stress levels in premature infants.
      We measured all the variables 10 min before, immediately after, and 10 min after bathing, except for the crying time. The crying time was measured from the start of the bath to the end. The study was conducted at least 24 h post-birth on the preterm infants with no birth asphyxia, fed at least 1–3 h before bath, no analgesic sedation treatment before bathing, and stable the vital signs. The parents fully understood and volunteered to participate in this study, at the NICU of a hospital in China. Newborns who were critically ill, not eligible for baths, and unexplained crying before bathing were excluded from the study.

      Preparation for bath

      All the baths in the study were conducted by the same researcher who was trained in newborn bathing. Therefore, the bath time and order of the two groups were the same. Bathing hours were kept uniform from 8:00 a.m. to 9:00 a.m., with controlled bath time of 5 min per infant and constant environmental factors such as 1) bath water temperature (37–38 °C); 2) bathroom temperatures (26–28 °C); 3) relative humidity (50–60%); 4) indoor fresh and dry air-ventilated, following the 30-min ultraviolet sterilization before and after using the bathroom; and 5) circulating air in the bathroom after bathing.
      10 min before bathing, experimental data of infants were measured without the change in position and state. The items such as newborn bath basins, disposable plastic diaphragm, water thermometer, etc., were prepared beforehand except for the unique disposable bath towel of the experimental group.

      Application of bathing methods

      SB group bathing method: In a naked state, infants body was moderately wrapped by the bath towel in a single layer, maintaining a curvy midline position, with the natural bending of the torso, arms, and legs, and slowly soaking it in the warm water of the tub, keeping the waterline up to shoulder level to ensure that infants feet hit bottom. Each part of the body was washed in the regular order of bathing. Before cleaning each body part of infants, a bath towel was opened, and after cleaning, it was not wrapped again. Next, the bath towel was opened for the other parts to clean until the bath towel was removed entirely.
      TTB group bath method: Everything was similar with the SB group except that there was no bath towel used to wrap the newborns. To give a naked bath in the bathtub, the water level depth was kept about 9–12 cm to keep infants bodies submerged in water till the shoulder. The operator grasped infants shoulders with thumb and fingers. The operator's forearm provided firm support to ensure that newborns do not experience any adverse event in water due to body twisting. The infants were washed clean to contaminated areas, in order of top-down, front-to-back following head, face, chest, abdomen, limbs, etc.

      After bath procedures

      After bathing, infants in both groups were dried and kept warm to ensure the umbilical cord and buttocks were appropriately clean and dried. Experimental data were measured immediately after and 10 min after bathing.

      Sample size

      The G-power 3.1.9.2 was used to calculate the sample size by holding the medium effect size (0.15), α = 0.05, power (1-β) = 0.90. Based on the relevant review of the literature and the specified calculation, the minimum sample size of 50 newborns was required, with 25 newborns in each group. Therefore, the study was designed to be conducted with 60 newborns, where randomization was determined by the computer, with 30 newborns in each group, in case of unforeseeable possible loss of participants.

      Data analysis

      Two researchers checked the data for the accuracy, and feeded the data into SPSS.V.22 for analysis. Measurement data were done to test the normality, with normal distribution and were described by the standard deviation (SD). Thereafter the t-test was used for statistical analysis. Continuous variables were shown in frequency & percentage and analyzed using the chi-square test. A p-value of p < 0.05 was considered statistically significant.

      Results

      Sample characteristics

      After obtaining the informed consent from the parents, the researchers used the “Participant Information Form” to collect the information about the infants and mother. The final sample size consisted of 30 infants in the SB and TTB groups, with total of 60 participants. The differences in infants between two groups such as postnatal age, gender, birth weight, weight at bath time (grams), Apgar score, time from the last feeding time were not found to be statistically significant (P > 0.05). In the case of maternal record, the age of the pregnancy, gestational period, the number of births, week of maternal pregnancy, mode of delivery, and absence of pregnancy-associated morbidities were comparable for both the groups with no observed statistical significance (P > 0.05) (Table 1).
      Table 1Demographic and clinical characteristics of the participants in the swaddled bathing and traditional tub bathing groups.
      CharacteristicsSB (n = 30)TTB (n = 30)t/x2p
      Mean ± SDMean ± SD
      Infants
      Postnatal age (days)8.77 ± 8.4439.80 ± 7.788−0.493a0.624
      Gender (N,%)Male13(43.3)16(53.3)0.601b0.438
      Female17(56.7)14(46.7)
      Birth weight (grams)2899.83 ± 636.1762881.17 ± 874.7000.095a0.925
      weight at bath time (grams)3067.33 ± 481.0353055.67 ± 680.9510.077a0.939
      Apgar score, 1 min9.47 ± 1.1069.17 ± 1.4640.896a0.374
      Apgar score, 5 min9.83 ± 0.4619.97 ± 1.829−0.387a0.700
      From the last feeding time (min)86.40 ± 15.08786.93 ± 16.193−0.132a0.895
      Maternal
      The age of pregnancy30.80 ± 3.79131.07 ± 5.420−0.221a0.826
      Number of pregnancies2.23 ± 1.4552.47 ± 1.332−0.648a0.520
      Number of productions1.50 ± 0.5721.67 ± 0.661−1.044a0.301
      Gestational age (weeks)34.00 ± 1.66132.87 ± 2.3152.178a0.033
      Birth type(N,%)Vaginal13(43.3)11(36.7)0.278b0.598
      Cesarean section17(56.7)19(63.3)
      Pregnancy disease (N,%)Yes13(43.3)12(40)0.069b0.793
      No17(56.7)18(60)
      Note. aStudent t-Test, bChi-square test.

      Assessment of physiological parameters

      We compared the body temperature, respiratory rate, heart rate, and oxygen saturation levels 10 min before, immediately after, and 10 min after bathing between the two groups. The physiological indicators 10 min before the bath in the two groups were comparable and had no statistical significance (P > 0.05) difference.
      Both bathing methods affected the body temperature before and after bathing in the premature infants, which decreased during but rose again ten minutes after the bathing. There was no difference between the groups on body temperature change caused by these two bathing methods (P > 0.05) immediately after bath. However, body temperature of infants risen significantly in the SB group than the TTB group, 10 min after the bathing.
      Both bathing methods led to the changes in respiratory rate and heart rate of the newborns during bathing. During the bathing process, premature infants respiratory rate and heart rate increased in the TTB group. In contrast, in the SB group, this increase was comparatively more minor. However, in both groups, respiratory rate and heart rate were stabilized 10 min after bathing. Bathing also led to changes in oxygen saturation in both groups of premature infants. However, the decline in oxygen saturation in the TTB group was more significant than that of premature infants in the SB group. Following 10 min after bathing, both groups oxygen saturation values rose again, though the fluctuation of oxygen saturation in the SB group was less than the TTB group (Table 2).
      Table 2Comparison of body temperature, breathing, heart rate and oxygen saturation levels in the swaddled bathing and traditional tub bathing groups.
      VariablesSB (n = 30)TTB (n = 30)tap
      Mean ± SDMean ± SD
      Body temperature (°C)
      Before bathing36.780 ± 0.297636.830 ± 0.2950−0.6540.516
      After bathing36.607 ± 0.299336.535 ± 0.25781.0170.313
      10 min after bathing36.850 ± 0.206436.723 ± 0.24172.8130.033*
      Respiratory rate (per minute)
      Before bathing41.37 ± 1.40241.07 ± 1.6390.7620.449
      After bathing43.50 ± 1.30646.17 ± 1.783−6.608<0.001**
      10 min after bathing42.00 ± 1.25943.07 ± 1.337−3.180<0.001**
      Heart rate (per minute)
      Before bathing130.23 ± 10.500141.40 ± 14.936−3.3500.401
      After bathing138.50 ± 9.982150.37 ± 13.682−3.838<0.001**
      10 min after bathing132.80 ± 10.682143.53 ± 13.452−3.431<0.001**
      Oxygen saturation levels (%)
      Before bathing96.33 ± 1.80794.03 ± 1.7520.1250.901
      After bathing94.03 ± 1.75291.43 ± 1.8325.618<0.001**
      10 min after bathing96.93 ± 2.14994.47 ± 2.1294.467<0.001**
      Note. aStudent t-Test, *p < 0.05, **p < 0.001.

      Stress assessment

      While comparing the bathing time and crying duration of the two groups, it has been observed that the SB group bath time was 301.93 ± 14.377(s) more than that of the TTB group 280.33 ± 20.215 (s). However, the crying duration of premature infants in the TTB group was 94.43 ± 41.625(s) greater than 32 ± 24.740 (s) in the SB group during bathing. The NSS scores of two groups of these premature infants had no statistical difference 10 min before bathing. However, the NSS score of the TTB group was more significant than that of the SB group, immediately after and ten minutes after bathing (Table 3, Table 4).
      Table 3Comparison of crying time in the swaddled bathing and traditional tub bathing groups.
      VariablesSB (n = 30)TTB (n = 30)tap
      Mean ± SDMean ± SD
      Crying time (s)32 ± 24.74094.43 ± 41.625−7.062<0.001**
      Note. aStudent t-Test, **p < 0.001.
      Table 4Comparison of newborn stress scale score in the swaddled bathing and traditional tub bathing groups.
      NSS scoreSB(n = 30)TTB(n = 30)tap
      Mean ± SDMean ± SD
      Before bathing3.47 ± 1.7954.93 ± 1.780−3.1780.402
      After bathing4.60 ± 1.9937.73 ± 1.799−6.39<0.001**
      10 min after bathing2.53 ± 1.1675.60 ± 1.499−8.841<0.001**
      Note. aStudent t-Test, **p < 0.001.

      Discussion

      Premature infants have underdeveloped skin barriers, thinner skin, high susceptibility to skin infections and irritants, and impaired external heat stimulation that can alter the skin's blood flow (
      • Albahrani Y.
      • Hunt R.
      Newborn skin care.
      ;
      • Kusari A.
      • Han A.M.
      • Virgen C.A.
      • Matiz C.
      • Rasmussen M.
      • Friedlander S.F.
      • Eichenfield D.Z.
      Evidence-based skin care in prater infants.
      ;
      • Lund C.
      Issues in newborn skin care.
      ). Studies have shown that bathing can lead to deterioration of vital signs in infants, such as changes in heart rate and respiratory rate, temporary reduction in oxygen saturation levels, and hypothermia (
      • Bembich S.
      • Fiani G.
      • Strajn T.
      • Sanesi C.
      • Demarini S.
      • Sanson G.
      Longitudinal responses to weighing and bathing procedures in preterm infants.
      ). Bathing can also increase distress in premature infants, further enhanced with consecutive care procedures (
      • Liaw J.J.
      • Yang L.
      • Yuh Y.S.
      • Yin T.
      Effects of tub bathing procedures on preterm infants’ behavior.
      ). Therefore, an essential focus of bathing in premature infants is to reduce the bathing procedures related to stimulation (
      • Edraki M.
      • Paran M.
      • Montaseri S.
      • Razavi N.M.
      • Montaseri Z.
      Comparing the effects of swaddled and conventional bathing methods on body temperature and crying duration in premature infants: A randomized clinical trial.
      ), at the same time to provide the benefits of bathing. Assessment of physiological indicators reflected that the degree of stimulation in these infants causes instability of these parameters, although stabilizing these indicators in the newborn is essential.
      In this study, both the bathing patterns resulted drop in the body temperature of premature infants. Although the two bathing groups can cause hypothermia, the SB group was effective in restoring body temperature after bathing. The current study results concur with the previously reported results of Çaka (
      • Çaka S.Y.
      • Gözen D.
      Effects of swaddled and traditional tub bathing methods on crying and physiological responses of newborns.
      ) study. In the present study, both types of bathing caused alteration in the respiratory rate, heart rate, and oxygen saturation immediately after and 10 min after bathing. This observation further confirms that bathing can affect physiological indicators of premature infants. Among the studied indicators, the increase in respiratory rate and heart rate after bathing and the decrease at ten minutes after bathing were relatively smaller than that of the naked bath group.
      Bathing resulted in decreased oxygen saturation levels in premature infants in the SB and TTB groups. Still, it increased after ten minutes of bathing, which contributed to the end of the bathing procedure, the reduction in care operations, and other stimuli. The alteration in terms of decline and increase of oxygen saturation in the SB group was minor than in the TTB group. Further, the overall stability was better in the SB group than in the TTB group.
      Numerous studies have found that (
      • Çaka S.Y.
      • Gözen D.
      Effects of swaddled and traditional tub bathing methods on crying and physiological responses of newborns.
      ;
      • Ceylan S.S.
      • Bolւşւk B.
      Effects of swaddled and sponge bathing methods on signs of stress and pain in premature newborns: Implications for evidence-based practice.
      ;
      • Çınar N.
      • Yalnızoğlu Ç.S.
      • Uslu Y.H.
      Effect of newborn bathing training with the swaddled and tub bathing methods given to primiparous pregnant women on the mother’s experience, satisfaction and newborn’s stress during the first bathing of the newborn at home: A mixed method study.
      ;
      • de Freitas P.
      • Bueno M.
      • Holditch-Davis D.
      • Santos H.P.
      • Kimura A.F.
      Biobehavioral responses of preterm infants to conventional and swaddled tub baths: A randomized crossover trial.
      ;
      • Edraki M.
      • Paran M.
      • Montaseri S.
      • Razavi N.M.
      • Montaseri Z.
      Comparing the effects of swaddled and conventional bathing methods on body temperature and crying duration in premature infants: A randomized clinical trial.
      ) swaddled bathing not only effectively maintains the newborn's body temperature, oxygen saturation levels, and HR within the normal range but also reduces the crying time during bathing, which has a positive impact in reducing the stress and pain levels associated with bathing. In addition, it is reported to reduce the behavioral stress symptoms in newborns during bathing, such as crying, grimacing, abnormal muscle tone, etc., and makes infants feel relaxed.
      Stress can adversely affect the physical and mental development of premature infants. Excessive stress induces negative consequences on genetic and brain function as well as impacts the social and emotional well-being of premature infants (
      • Craciunoiu O.
      • Holsti L.
      A systematic review of the predictive validity of neurobehavioral assessments during the preterm period.
      ;
      • Fumagalli M.
      • Provenzi L.
      • De Carli P.
      • Dessimone F.
      • Sirgiovanni I.
      • Giorda R.
      • Montirosso R.
      From early stress to 12-month development in very preterm infants: Preliminary findings on epigenetic mechanisms and brain growth.
      ). Furthermore, stress is highly detrimental to early childhood development and contributes to future diseases (
      • Dimitrova N.
      • Turpin H.
      • Borghini A.
      • Morisod H.M.
      • Urben S.
      • Müller-Nix C.
      Perinatal stress moderates the link between early and later emotional skills in very preterm-born children: An 11-year-long longitudinal study.
      ). Swaddled bathing is a harmless and safe method of care that provides a calm, stress-free bathing experience for newborns by simulating a familiar and safe uterine environment(
      • Fernández D.
      • Antolín-Rodríguez R.
      Bathing a premature infant in the intensive care unit: A systematic review.
      ).
      This study measured the total time of crying in premature infants in different bathing modes, combined with the NSS scale score, to evaluate the stress level of premature infants. Both groups NSS scores had no statistical significance and were comparable before bathing. However, the preterm infants in the TTB group cried for longer than the SB group during the bath. In addition, the pressure score of the TTB group was also higher than that of the SB group soon after and ten minutes after bathing.
      Interestingly, the data was measured immediately after the bath, and the increase in the pressure score of the TTB group was significantly more significant than that of the SB group. This not only means that the bathing process of TTB causes more stress than SB on premature infants but also continues to affect them for longer duration.

      Practice implications

      The study assessed the effects of SB and TTB on premature infants. Our data showed that bathing itself could bring noxious stimuli and cause stress to the developing premature neonate. However, the results confirmed the benefits of SB for premature infants. Therefore, SB is recommended for preterm infants admitted to intensive care units to improve their care quality. Furthermore, our results enrich the experimental data and feasibility studies on SB in different countries. Overall, our findings may help in healthcare and social interventions to facilitate the development of premature infants.

      Limitations

      This study did not classify early or late-to-late-stage premature infants. However, several pieces of literature are available describing the effects of bathing on premature infants in the middle and late stages. In addition, smaller sample size was one of the limitations of this study as all the included subjects were enrolled based on the strict inclusion criteria. Lastly, similar studies are recommended to be conducted on a larger cohort to validate the results from the present study.

      Conclusion

      The study compared the TTB with the SB technique. The results demonstrated that the SB maintains the stable physiological indicators of premature infants, moreover the stress on premature infants was also minimal. Although the advantages of SB have been proved in various regions, this study is the first to validate its effect and feasibility on China's preterm infants.

      Author statement

      YT and LS designed and performed the study. YT and LS drafted the manuscript. YT, HAWA, YY participated in the design of the study. YT, LS and HB performed the statistical analysis and interpretation of data. All authors read and approved the final manuscript.

      Declaration of Competing Interest

      None.

      References

        • Albahrani Y.
        • Hunt R.
        Newborn skin care.
        Pediatric Annals. 2019; 48: 11-15
        • Beck S.
        • Wojdyla D.
        • Say L.
        • Pilar Bertran A.
        • Meraldi M.
        • Harris Requejo J.
        • Van Look P.
        The worldwide incidence of preterm birth: A systematic review of maternal mortality and morbidity.
        Bulletin of the World Health Organization. 2010; 88: 31-38
        • Bembich S.
        • Fiani G.
        • Strajn T.
        • Sanesi C.
        • Demarini S.
        • Sanson G.
        Longitudinal responses to weighing and bathing procedures in preterm infants.
        The Journal of Perinatal & Neonatal Nursing. 2017; 31: 67-74
        • Blencowe H.
        • Cousens S.
        • Oestergaard M.Z.
        • Chou D.
        • Moller A.B.
        • Narwal R.
        • Lawn J.E.
        National, regional, and worldwide estimates of preterm birth rates in 2010 with time trends since 1990 for selected countries: A systematic analysis and implications.
        Lancet. 2012; 379: 2162-2172
        • Burdall O.
        • Willgress L.
        • Goad N.
        Neonatal skin care: Developments in care to maintain neonatal barrier function and prevention of diaper dermatitis.
        Pediatric Dermatology. 2019; 36: 31-35
        • Çaka S.Y.
        • Gözen D.
        Effects of swaddled and traditional tub bathing methods on crying and physiological responses of newborns.
        Journal for Specialists in Pediatric Nursing. 2018; 23
        • Cerasani J.
        • Ceroni F.
        • De Cosmi V.
        • Mazzocchi A.
        • Morniroli D.
        • Roggero P.
        • Giannì M.L.
        Human milk feeding and preterm infants’ growth and body composition: A literature review.
        Nutrients. 2020; 12
        • Ceylan S.S.
        • Bolışık B.
        Examining psychometric properties of newborn stress scale.
        ACU Sağlık Bil Derg. 2017; 2: 97-103
        • Ceylan S.S.
        • Bolւşւk B.
        Effects of swaddled and sponge bathing methods on signs of stress and pain in premature newborns: Implications for evidence-based practice.
        Worldviews on Evidence-Based Nursing. 2018; 15: 296-303
        • Çınar N.
        • Yalnızoğlu Ç.S.
        • Uslu Y.H.
        Effect of newborn bathing training with the swaddled and tub bathing methods given to primiparous pregnant women on the mother’s experience, satisfaction and newborn’s stress during the first bathing of the newborn at home: A mixed method study.
        Japan Journal of Nursing Science. 2020; 17: 123-163
        • Cooke A.
        • Bedwell C.
        • Campbell M.
        • McGowan L.
        • Ersser S.J.
        • Lavender T.
        Skin care for healthy babies at term: A systematic review of the evidence.
        Midwifery. 2018; 56: 29-43
        • Craciunoiu O.
        • Holsti L.
        A systematic review of the predictive validity of neurobehavioral assessments during the preterm period.
        Physical & Occupational Therapy in Pediatrics. 2017; 37: 292-307
        • Dimitrova N.
        • Turpin H.
        • Borghini A.
        • Morisod H.M.
        • Urben S.
        • Müller-Nix C.
        Perinatal stress moderates the link between early and later emotional skills in very preterm-born children: An 11-year-long longitudinal study.
        Early Humandevelopment. 2018; 121: 8-14
        • Edraki M.
        • Paran M.
        • Montaseri S.
        • Razavi N.M.
        • Montaseri Z.
        Comparing the effects of swaddled and conventional bathing methods on body temperature and crying duration in premature infants: A randomized clinical trial.
        Journal of Caring Sciences. 2014; 3: 83-91
        • Fernández D.
        • Antolín-Rodríguez R.
        Bathing a premature infant in the intensive care unit: A systematic review.
        Journal of Pediatric Nursing-Nursing Care of Children & Families. 2018; 42: 52-57
        • de Freitas P.
        • Bueno M.
        • Holditch-Davis D.
        • Santos H.P.
        • Kimura A.F.
        Biobehavioral responses of preterm infants to conventional and swaddled tub baths: A randomized crossover trial.
        The Journal of Perinatal & Neonatal Nursing. 2018; 32: 358-365
        • Fumagalli M.
        • Provenzi L.
        • De Carli P.
        • Dessimone F.
        • Sirgiovanni I.
        • Giorda R.
        • Montirosso R.
        From early stress to 12-month development in very preterm infants: Preliminary findings on epigenetic mechanisms and brain growth.
        PLoSOne. 2018; 13: 1902-1906
        • Gucev Z.
        Newborn screening in southeastern Europe.
        Molecular Genetics and Metabolism Reports. 2017; 13: 13
        • Incorpora G.
        • Pavone P.
        • Cocuzza M.
        • Privitera M.
        • Pavone L.
        • Ruggieri M.
        Neonatal onset of bath-induced alternating hemiplegia of childhood.
        European Journal of Paediatric Neurology. 2010; 14: 192-193
        • Juan L.
        • Wang Q.
        • Hongmin W.
        • Yang Y.
        • Lizhong D.
        • Yao Y.
        • Wei K.
        A survey of neonatal births in maternity departments in urban China in 2005.
        Chinese Journal of Contemporary Pediatrics. 2012; 14: 7-10
        • Küçük A.D.
        • İnal S.
        The effect of individualized developmental care practices in preterm infants.
        Complementary Medicine Research. 2020; 27: 97-104
        • Kusari A.
        • Han A.M.
        • Virgen C.A.
        • Matiz C.
        • Rasmussen M.
        • Friedlander S.F.
        • Eichenfield D.Z.
        Evidence-based skin care in prater infants.
        Pediatric Dermatology. 2019; 36: 16-23
        • Liaw J.J.
        • Yang L.
        • Yuh Y.S.
        • Yin T.
        Effects of tub bathing procedures on preterm infants’ behavior.
        Journal of Nursing Research. 2006; 14: 297-305
        • Lund C.
        Bathing and beyond: Current bathing controversies for newborn infants.
        AdvNeonatalCare. 2016; 16: 13-20
        • Lund C.
        Issues in newborn skin care.
        Advances in Neonatal Care. 2016; 16: 1-2
        • Montirosso R.
        • Provenzi L.
        • Fumagalli M.
        • Sirgiovanni I.
        • Giorda R.
        • Pozzoli U.
        • Borgatti R.
        Serotonin transporter gene (SLC6A4) methylation associates with neonatal intensive care unit stay and 3-month-old temperament in preterm infants.
        Child Development. 2016; 87: 38-48
        • Nechay A.
        • Stephenson J.B.
        Bath-induced paroxysmal disorders in infancy.
        European Journal of Paediatric Neurology. 2009; 13: 203-208
        • Smith G.C.
        • Gutovich J.
        • Smyser C.
        • Pineda R.
        • Newnham C.
        • Tjoeng T.H.
        • Inder T.
        Neonatal intensive care unit stress is associated with brain development in preterm infants.
        Annals of Neurology. 2011; 70: 541-549
        • Suzuki M.
        • Shimbo T.
        • Ikaga T.
        • Hori S.
        Incidence and characteristics of bath-related accidents.
        Internal Medicine. 2019; 58: 53-62
        • Taşdemir H.O.
        • Efe E.
        The effect of tub bathing and sponge bathing on neonatal comfort and physiological parameters in late preterm infants: A randomized controlled trial.
        International Journal of Nursing Studies. 2019; 99: 1033-1037
        • Vogel J.P.
        • Chawanpaiboon S.
        • Moller A.B.
        • Watananirun K.
        • Bonet M.
        • Lumbiganon P.
        The global epidemiology of preterm birth.
        Best Practice & Research. Clinical Obstetrics & Gynaecology. 2018; 52: 3-12