PubMed1992
Mechanical ventilation of mature or premature newborns is supposed to provide pulmonary gas exchange while causing minimal side effects to the respiratory system and circulation of the infants. A certain degree of alveolar ventilation, for example, can be achieved by different ventilator settings with different airway pressures (Fig. 1), and thus the corresponding effects on lung mechanics, barotrauma, and circulation differ. Parameters indicating optimal ventilator settings cannot be measured often enough in routine daily care and sometimes are difficult to interpret because of complex interactivity factors. The aim of the computer program "RespCalc" is to shorten the empirical steps of adapting respirator settings to the status of the ventilated patient by calculating the necessary data and drawing patient-specific nomograms. The computer program "RespCalc" makes use of the mathematical relationships characterizing the determinants of lung mechanics. The following data are necessary for use of the program: patient identification, weight, alveolar ventilation, recent paCO2, compliance, and resistance. By using the time-constant tau, the minimal inspiratory time as well as a maximal possible respirator rate are displayed without inducing inadvertent PEEP at a ratio of 1:1. Afterward, the planned figures of the different respirator rates and corresponding inspiration times must be typed in. The program simultaneously checks whether the previously calculated minimal figures for in- and exhalation time are maintained. If the above-mentioned figures and the typed-in ones differ, an optical and acoustical error message appears, and thus the user is forced to correct the problem.(ABSTRACT TRUNCATED AT 250 WORDS)