Clinical, biochemical, and haemodynamic studies in man during refractory hypotension

Abstract

1. There appear to be four main clinical postoperative presentations in which patients most commonly have refractory hypotension: (i) thos4 with unrecognized, persisting blood-volume deficit, (ii) those with severe sepsis, (iii) those with complicating myocardial failure, (iv) those who have had extensive surgical procedures with local complications. 2. These patients commonly present with a coexisting metabolic acidosis and/or hyponatraemia. 3. In view of these observations, it is suggested that in the treatment of these patients with refractory hypotension blood and fluid loss be fully replaced. A persisting, unrecognized blood-volume deficit often in fact still exists in these patients. Central venous pressure (CVP) can be a useful guide to this replacement therapy. If during volume replacement the arterial bloodl pressure rises, before the CVP, then in all likelihood volume deficit hypotension shock existed. If, however, CVP increases steadily and before the arterial blood pressure rises, then the transfusion rate must be decreased and chemical therapy with cardiotonic agents used, in the form of a digitjalis preparation, isopropyl norepinephrine, or calcium chloride or gluconate. In either case concurrent correction of the acid-base defect is carried out. Metabolic acidosis and hyponatraemia can be treated effectively with NaHCO3. Appropriate antibacterial therapy is given where indicated. 4. Patients considered to be in a potentially "irreversible" or irefractory hypotensive status may, in fact, show surprising reversibility and suirvivability, once the pathophysiologic defect is recognized and repaired. © 1965 Canadian Anesthesiologists.