Background

Due to global immaturity, very low birthweight (VLBW) infants (<1,500 g) require auxiliary thermal and respiratory care. However, the impact of respiratory care on infant thermal stability remains unclear.

Aims

Examine the association between VLBW infant body temperatures over time and respiratory support type (mechanical ventilation (MV), continuous positive airway pressure (CPAP), room air (RA)), respiratory care interventions, and nursing care.

Design

Exploratory, longitudinal, and correlational design.

Subjects

12 infants <29 weeks' gestation (median = 27.1, 25.9-27.9) and <1,200 g (median = 865 g, 660-1,050 g).

Measurements

Minute-to-minute body temperatures and continuous video data were collected over the first 5 days of life. Video data was coded with Noldus Observer®XT software. Respiratory support was retrieved from the electronic health record. Hierarchical multi-level, mixed-effects models for intensive longitudinal data examined the associations.

Results

Body temperatures were associated with respiratory support type, respiratory care, and care events (all p < .0001). Pairwise comparison found significant differences in body temperatures between all respiratory support types (all p < .0001). The covariate-adjusted risk of hypothermia (<36.5 °C) was significantly greater during MV vs. RA (aOR = 2.6); CPAP vs. MV (aOR = 1.2); CPAP vs RA (aOR = 3.1); respiratory care vs. other types of care (aOR = 1.5); care event vs. closed portholes (aOR = 2.6).

Conclusion

Our results found an association between VLBW infant thermal instability and respiratory support type, respiratory care, and care events. Larger studies with advanced longitudinal analysis are needed to assess the causal impact of these interventions on infant temperatures over time, as well as the implications of longitudinal thermal instability on infant outcomes.