Physiological Safety and Behavioral Comfort of Swaddle Bathing in Preterm Infants

Effects of Swaddle Bathing on Physiological Regulation and Stress-Reducing Behaviors in Preterm Infants in the Neonatal Intensive Care Unit: A Randomized Controlled Trial

Background and Purpose: Bathing is a routine but essential part of care for preterm infants in the Neonatal Intensive Care Unit (NICU). However, traditional tub bathing can be a significant source of stress for these vulnerable infants, potentially leading to fluctuations in body temperature, heart rate, and oxygen levels. Swaddle bathing-a technique where the infant is wrapped in a light cloth during the bath-is thought to provide a sense of security and better physiological stability.

The goal of this pilot randomized controlled trial is to compare the effects of swaddle bathing versus conventional tub bathing in preterm infants. The researchers want to determine if swaddle bathing is as safe as traditional methods while being more comfortable for the baby.

Main Questions to Answer:

• Is swaddle bathing non-inferior to (as safe as) conventional tub bathing regarding the infant's physiological stability (e.g., body temperature and heart rate)?
• Does swaddle bathing significantly reduce stress-related behaviors and crying in preterm infants compared to conventional bathing?

Study Design and Procedure:

Participants will be randomly assigned to one of two groups:

1. Experimental Group: Infants will receive swaddle bathing, where they remain snugly wrapped in a towel or wrap while being gently immersed in water.
2. Control Group: Infants will receive conventional tub bathing according to standard hospital protocols.

During and after the bath, the research team will monitor the infants' vital signs and video-record their behavioral responses (such as facial expressions and limb movements) to evaluate their level of comfort and stress. The results of this study will provide preliminary evidence to help clinical nurses decide the best bathing practices for promoting the neurodevelopmental care of preterm infants.

Study Overview:

This pilot randomized controlled trial (RCT) aims to evaluate the physiological safety and behavioral comfort of swaddle bathing compared to conventional tub bathing in preterm infants. The study is designed to provide preliminary evidence on whether swaddle bathing serves as a neurodevelopmental care intervention that maintains thermal and cardiovascular stability while reducing stress-related behaviors during a routine nursing procedure in the Neonatal Intensive Care Unit (NICU).

Research Methodology:

Participants will be recruited from a NICU and randomly assigned to either the experimental group (swaddle bathing) or the control group (conventional tub bathing) using a block randomization method. To ensure safety, all bathing procedures will be conducted by trained neonatal nurses and monitored for any signs of physiological distress.

Intervention Protocols:

Standardized Environmental Conditions To minimize the confounding effects of hunger or satiety on behavioral responses, all baths were scheduled approximately 30 to 60 minutes before the next scheduled feeding (or 1 hour after feeding). To ensure consistency across both groups, all bathing procedures were conducted in a temperature-controlled environment maintained at 25-26°C. A standardized stainless-steel basin (33 cm diameter, 10 cm height) was filled to 80% capacity with water at 39-40°C. The duration of the bathing procedure was strictly limited to 5 minutes for all participants.

1. Experimental Group (Swaddle Bathing): The infant is snugly wrapped in a thin cotton cloth or swaddle. While maintaining the wrap, the infant is gently immersed into a tub of warm water (39 to 40°C). The nurse uncoils the wrap only partially to wash specific body parts, ensuring the infant remains contained and secure throughout the process.
2. Control Group (Conventional Tub Bathing): The infant is undressed and placed directly into the tub according to standard hospital protocol, with the nurse providing manual support but without the use of a stabilizing wrap.

Data Collection and Outcome Measurement:

The study will record data at three time points: baseline (pre-bath, T0), immediately post-bath (T1), and 10 minutes post-bath (T2).

• Physiological Safety:

  • Body Temperature: Measured using a rapid electronic thermometer (verified by the Bureau of Standards, Metrology and Inspection, MOEA; License No. 001618). Axillary temperature was measured, with the device remaining in place for 3-5 minutes after the beep to ensure accuracy.
  • Vital Signs Monitoring: Heart rate (HR) and oxygen saturation (SpO2) were measured using a General Electric B105 portable physiological monitor (License No. 022655). The device is calibrated and maintained every six months by biomedical engineers.

• Behavioral Comfort: Infants will be video-recorded to assess stress signals and comfort levels. Blinded observers will use standardized neonatal pain and stress scales (e.g., Anderson Behavioral State Scale) to score the frequency of crying and stress-related motor activities.

Statistical Analysis:

Data will be analyzed using descriptive statistics and generalized estimating equations (GEE) to account for the repeated measures over time. As a pilot study, the results will be used to calculate the effect size required for a future full-scale clinical trial.

Inclusion Criteria

• Gestational age between 32 and 36 weeks and 6 days
• Birth weight greater than 1,500 grams
• Clinically stable as determined by the attending neonatologist
• Receiving the first bath after birth

Exclusion Criteria

• Major congenital anomalies, such as cyanotic heart disease, gastroschisis, or open spinal defects
• Severe intraventricular hemorrhage (Grade III or IV)
• Skin impairments or open wounds that contraindicate water immersion, including surgical sites
• Continuous use of sedatives or muscle relaxants that may interfere with behavioral assessments