Resuscitation of the critically ill patient. Use of branched-chain decision trees to improve outcome.
The algorithm approach provides criteria based on decision rules for expeditious monitoring, diagnostic and therapeutic decisions; algorithms are particularly useful in crisis situations, in which time is of great importance, for example, in the resuscitation of emergency patients. Because of its objectivity and usefulness as a teaching tool, this algorithmic approach is of practical benefit in the training of residents and students in teaching hospitals, as well as in the community hospital where less experienced physicians manage hypotensive emergency patients more infrequently. In a few instances there has been some reluctance to use the algorithm, but most often it was found to be useful in organizing the work-up and establishing therapeutic priorities. A second branched-chain decision tree was designed for use after the initial resuscitation in hemodynamically unstable patients who only had CVP catheters but were suspected of having hypovolemia. In this algorithm, MAP, HR, urine output, Hct, and CVP are used as criteria. The underlying premise under these conditions was to evaluate increments of volume therapy without exceeding safe CVP pressures (less than 18 mm Hg) in order to obviate fluid overloading. A third algorithm for ICU patients with pulmonary artery catheters was developed from decision rules based on objective physiologic, heuristic, survival data as the criteria for post-trauma and postoperative patients who were critically ill despite apparent success with the initial resuscitation and CVP algorithms. The improved mortality in prospective studies supports the hypothesis that compensatory responses of the survivors are the major determinants of outcome.