Adjustability and Adaptability Are Critical Characteristics of Pediatric Support Surfaces

Abstract

Significance: Pressure ulcers (PUs) in newborns and children are remarkably different from those in adults, both in their possible causal factors and in the etiology and biomechanical pathways for tissue damage. Recent Advances: Pediatric muscle and fat tissue structures are overall softer than those of adults, making newborns and young children more susceptible to deformation-inflicted injuries at their weight-bearing soft tissues. Critical Issues: The unique medical environment of neonatal and pediatric intensive care units, which is overloaded with medical devices, wiring, tubing, electrodes, and so on, is, in fact, an extrinsic risk factor for device-related PUs, since accidently misplaced tubes, wires, or electrodes can become trapped between the skin and the mattress, causing large sustained soft tissue deformations around them. Future Directions: Mattresses that are being used in neonatal and pediatric intensive care units must be able to respond to frequent movements and changing positions and also be able to effectively adapt and conform around such misplaced tubing or wires, which might contact the body and deform soft tissues. We used computer simulations of a tube caught under a preterm neonate's arm in a supine position to illustrate what adaptability of the support surface means in such cases. Our present simulations indicate that an air-cell-based technology provides considerably better protection against PUs in such cases, as the air-cells are able to locally buckle and conform around objects that are stiffer than the pediatric tissues (e.g., wires, tubes, electrodes), which minimizes exposure to tissue deformations.

Amit Gefen, PhD

Figure 1.

An illustration showing the differences in anatomy, physiology, and tissue biomechanics between adults and infants, in the context of pressure ulcer risks: (a) adult MRI tissue structures in an axial cut through the arm. (b) An increased fat/muscle ratio in an infant's arm compared to that of a scaled-down adult. (c) Increased deformations in muscle and fat tissues, due to reduced tissue stiffness in an infant's arm, compared to those in a scaled-down adult. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound

Figure 2.

Finite element (FE) computational model of an axial cut through the upper arm of a 1.5 kg preterm neonate, in supine position, when a 2-mm tube is left between the skin and either a flat foam mattress (top panel) or an air-cell-based mattress (bottom panel). Zoom-in on the deformed FE meshes around the tubes is provided in the middle frames. Effective mechanical stress distributions in muscle and fat tissues are on the right. B, bone; M, muscle; F, fat; T, tube. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/wound