Anesthesiological problems related to the use of beta-sympathomimetic drugs for chronic and acute tocolysis.

Pregnant women treated with intravenous beta-sympathomimetics for acute or chronic tocolysis often show cardiovascular side-effects, mainly tachyarrhythmias, and electrolyte disorders, mainly hypokaliemia. Both create a potential hazard at the moment of induction of general anesthesia. For these patients one will use drugs exhibiting minimal hemodynamic side-effects and no oxytocic activity. Barbiturates as induction agent, and intravenous analgesics for maintenance of anesthesia after extraction of the neonate represent the safest solution. A short delay of ten minutes between administration of the beta-mimetic and induction of anesthesia avoids the coincidence of the maximal cardiovascular effects of the beta-mimetic with the stress of induction, and allows adequate preoxygenation of the patient.