AN EVALUATION OF THE PHYSICAL AND FUNCTIONAL-CHARACTERISTICS OF INFANT RESUSCITATORS

Self-inflating resuscitators (SIRs) are commonly used to assist ventil ation in the newborn. Despite their widespread use, there is limited i nformation available on the functional and physical characteristics of SIRs. We studied five new infant bag-valve units to compare their phy sical characteristics, including reservoir, accumulator, and dead spac e volumes (V(D)), pressure relief mechanism (PRM), inspiratory resista nce (R(I)), and functional mechanics including stroke volume (SV), fra ction of delivered oxygen (FDO2), and cycle frequency at -5-degrees-C, 20-degrees-C, and 49-degrees-C, using a test lung apparatus and exper ienced respiratory therapists. In addition, deficiencies and features that may render them less than ideal were sought. All SIRs met minimum standards for reservoir and accumulator volumes, R(I) (<20 CMH2O/L/se c), SV (20-70 ml), and FDO2 (>90%) as determined by the Canadian Stand ards Association (CSA) and the American Society for Testing of Materia ls (ASTM). However, the following deficiencies were noted: 1) MPR and Pulmanex(TM) had no PRM (ASTM requirement); 2) MPR could not cycle at -5-degrees-C; 3) the V(D)S for Pulmanex(TM) (10 ml) and MPR (15 ml) we re high; 4) the CPR connector broke during normal use, and the MPR con nector frequently disconnected; 5) the Laerdal expiratory valve was in competent; and 6) the Laerdal and CPR could be misassembled for use. O ur study shows that some commercially available SIRs do not meet all C SA and ASTM standards and may not be ideal in specific clinical situat ions. The choice of a SIR may be dictated by the clinical situation in which its use is intended.