. 2024 Feb 26;77(1):e20230260. doi: 10.1590/0034-7167-2023-0260

Chart 1. Characterization of hot water immersion use as an intervention for pain relief, São Paulo, São Paulo, Brazil, 2023.

Author Year Country	Objective	Design Level of evidence	Participants Study site Pain scale	Type of immersion, time and water temperature during intervention	Results Conclusion
INTERVENTION: HYDROTHERAPY
Vignochi C et al.; 2010; Brazil⁽²⁰⁾	Assess the effects of hydrotherapy on improving sleep quality and reducing pain in PTNB.	Uncontrolled clinical trial; Level III	12 PTNB; NICU; NFCS + physiological parameters	Hydrotherapy; 10 minutes; 37°C	Lower pain scores, HR, RR and longer sleep time.
Barbosa LPC et al.; 2015; Brazil⁽¹⁰⁾	Assess the impact of hydrotherapy on newborns admitted to hospital.	Quasi-experimental study; Level III	10 newborns >72 hours old; NICU; NIPS + physiological parameters	Hydrotherapy; 10 minutes; 37 and 38°C	Greater reduction in pain score, RR and HR.
Tobinaga WCO et al.; 2016; Brazil⁽⁸⁾	Investigate the effects of hydrotherapy on salivary cortisol, hemodynamics and pain level in PTNB.	Quasi-experimental study; Level III	15 PTNB; NICU; NIPS + physiological parameters + endocrine parameters	1 hydrotherapy session; 10 minutes; 37°C	There were no significant changes in the pain score, but there was a reduction in HR, RR and salivary cortisol level
Novakoski KRM et al.; 2018; Brazil⁽⁹⁾	Analyze the effects of hydrotherapy on pain and physiological variables in clinically stable PTNB.	Quasi-experimental study; Level III	22 PTNB; NICU; NFCS + physiological parameters	Hydrotherapy; 10 minutes; 36 and 37.5°C	Lower pain score immediately and after 10 minutes and lower HR.
Cecconello BW et al; 2021; Brazil⁽²¹⁾	Assess the effect of hydrotherapy on pain and vital signs of PTNB in the ICU.	Observational study; Level VI	54 medical records of PTNB; NICU; NFCS + physiological parameters	Hydrotherapy; 10 minutes; 36.5 and 37.5°C	Significant reduction in pain score, HR, RR and MAP.
INTERVENTIONS: IMMERSION BATH, SWADDLED OR “FIRST BATH”
Ceylan SS, et al.; 2018; Turkey⁽¹⁶⁾	Determine the effects of sponge baths and swaddle baths on pain, crying time, and physiological variables.	Randomized clinical trial; Level II	35 PTNB; NICU; ALPS-Neo + physiological parameters	Immersion bath with swaddling; Between 3.8 ± 0.6 minutes; 37.5±0.8°C	Lower pain score, HR, RR, crying time and stress score in swaddled bath.
Gunay U, et al; 2018; Turkey⁽²³⁾	Assess the difference between the pain of newborns who took a bath and those who did not.	Randomized clinical trial; Level II	70 newborns >28 weeks, with moderate or severe pain; 35 in the CG and IG; NICU; NIPS + physiological parameters	Immersion bath compared to no intervention; Between 2-3 minutes; 37 and 38°C	Greater reduction in pain score, HR and RR in the immersion bath.
Tasdemir HI, et al. 2019; Turkey⁽²²⁾	Assess the effectiveness of bath and sponge baths on the physiological parameters and comfort of late PTNB.	Randomized clinical trial; Level II	120 PTNB (34-36 weeks); NICU; COMFORTneo + physiological parameters scale	(Immersion) bath Average of 3.74 minutes; 37 and 38°C	Significant reduction in pain score and HR in immersion bath.
Lima RO, et al.; 2020; Brazil⁽¹⁴⁾	Compare the nursing intervention “First bath” with the “Institutional standard operating procedure (SOP) bath” on neonatal behavior.	Randomized controlled clinical trial; Level II	33 TNB, with 15 in the CG and 18 in the IG; Rooming-in; NIPS + physiological parameters	Infant’s first bath versus standard operating procedure bath; 14 minutes; 38°C	Lower pain score, HR and RR after the first bath intervention.

NB - newborn; PTNB - preterm newborn (<37 weeks); TNB - term newborn (>37 weeks); NICU - Neonatal Intensive Care Unit; CG - control group; IG - intervention group; HR - heart rate; RR - respiratory rate; MAP - mean arterial pressure; NIPS - Neonatal Infant Pain Scale; NFCS - Neonatal Facial Coding System; ALPS-Neo - Neonatal Pain and Stress Assessment Scale.