Light or Deep Pressure: Medical Staff Members Differ Extensively in Their Tactile Stimulation During Preterm Apnea

Abstract

Background: Even though tactile stimulation is common practice to terminate preterm apnea, the style and intensity of these interventions is not specified during theoretical or practical training and has never been clinically evaluated. Objective: The present study was designed to analyze the various modes of tactile stimulation used to terminate preterm apnea and measure the pressure intensity and frequency of these stimulations. Methods: A model with the size and weight of an actual preterm infant was equipped with sensor technology to measure stimulation pressure and frequency of tactile stimulation. Additionally a camera system was used to record hand positions and stimulation modes. Seventy medical staff members took part in the experiment. Results: We found extreme between subjects differences in stimulation pressure that could not be explained by professional experience but, to a degree, depended on apnea intensity. Pressures ranged from 11.11 to 226.87 mbar during low intensity apnea and from 9.89 to 428.15 mbar during high intensity apnea. The majority of participants used rhythmic stimulation movements with a mean frequency of ~1 Hz. Different modes (rubbing, squeezing, tickling, and tapping) and finger positions were used. Conclusion: Medical staff members intuitively adjust their tactile stimulation pressure depending on the premature infants' apnea intensity. However, mean pressure values varied greatly between subjects, with similar pressure ranges for low and high intensity apnea. The question remains which pressure intensities are necessary or sufficient for the task. It is reasonable to assume that some stimulation types may be more effective in rapidly terminating an apneic event.

Keywords: apnea of prematurity; neonatology; pressure sensor; stimulation frequency; treatment; very low birth weight.

Figure 1

Schematic representation of the experimental setting. Top: Model preterm infant inside the incubator. Bottom: Water filled pouch (pressure sensor) on the model's foot.

Figure 2

Illustration of typical finger positions and stimulation modes. Drawings by Anna Zender.

Figure 3

Boxplots of the average and maximal pressure values of the four stimulation types during low intensity apnea (LIA) and high intensity apnea (HIA). Fat horizontal lines mark the medians. Circles and stars indicate outlier values.