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D Porembka

Publications and source records attributed to D Porembka.

3 recordsLinked to original sources

A model for technology assessment as applied to closed loop infusion systems. Technology Assessment Task Force of the Society of Critical Care Medicine.

OBJECTIVES: To test a model for the assessment of critical care technology on closed loop infusion control, a technology that is in its early stages of development and testing on human subjects. DATA SOURCES: A computer-assisted search of the English language literature and reviews of the gathered data by experts in the field of closed loop infusion control systems. STUDY SELECTION: Studies relating to closed loop infusion control that addressed one or more of the questions contained in our technology assessment template were analyzed. Study design was not a factor in article selection. However, the lack of well-designed clinical outcome studies was an important factor in determining our conclusions. DATA EXTRACTION: A focus person summarized the data from the selected studies that related to each of the assessment questions. The preliminary data summary developed by the focus person was further analyzed and refined by the task force. Experts in closed loop systems were then added to the group to review the summary provided by the task force. These experts' comments were considered by the task force and this final consensus report was developed. DATA SYNTHESIS: Closed loop system control is a technological concept that may be applicable to several aspects of critical care practice. This is a technology in the early stages of evolution and much more research and data are needed before its introduction into usual clinical practice. Furthermore, each specific application and each device for each application (e.g., nitroprusside infusion, ventilator adjustment), although based on the same technological concept, are sufficiently different in terms of hardware and computer algorithms to require independent validation studies. CONCLUSIONS: Closed loop infusion systems may have a role in critical care practice. However, for most applications, further development is required to move this technology from the innovation phase to the point where it can be evaluated so that its role in critical car practice can be defined. Each application of closed loop infusion systems must be independently validated by appropriately designed research studies. Users should be provided with the clinical parameters driving each closed loop system so that they can ensure that it agrees with their opinion of acceptable medical practice. Clinical researchers and leaders in industry should collaborate to perform the scientifically valid, outcome-based research that is necessary to evaluate the effect of this new technology. The original model we developed for technology assessment required the addition of several more questions to produce a complete analysis of an emerging technology. An emerging technology should be systematically assessed (using a model such as the model developed by the Society of Critical Care Medicine), before its introduction into clinical practice in order to provide a focus for human outcome validation trials and to minimize the possibility of widespread use of an unproven technology.

Algorithms

Airway pressure release ventilation.

BACKGROUND: Elevated airway pressures during mechanical ventilation are associated with hemodynamic compromise and pulmonary barotrauma. We studied the cardiopulmonary effects of a pressure-limited mode of ventilation (airway pressure release ventilation) in patients with the adult respiratory distress syndrome. METHODS: Fifteen patients requiring intermittent mandatory ventilation (IMV) and positive end-expiratory pressure (PEEP) were studied. Following measurement of hemodynamic and ventilatory data, all patients were placed on airway pressure release ventilation (APRV). Cardiorespiratory measurements were repeated after a 2-hour stabilization period. RESULTS: During ventilatory support with APRV, peak inspiratory pressure (62 +/- 10 vs 30 +/- 4 cm H2O) and PEEP (11 +/- 4 vs 7 +/- 2 cm H2O) were reduced compared with IMV. Mean airway pressure was higher with APRV (18 +/- 5 vs 24 +/- 4 cm H2O). There were no statistically significant differences in gas exchange or hemodynamic variables. Both cardiac output (8.7 +/- 1.8 vs 8.4 +/- 2.0 L/min) and partial pressure of oxygen in arterial blood (79 +/- 9 vs 86 +/- 11 mm Hg) were essentially unchanged. CONCLUSIONS: Our results suggest that while airway pressure release ventilation can provide similar oxygenation and ventilation at lower peak and end-expiratory pressures, this offers no hemodynamic advantages.

Adult