Atropine and scopolamine can cause central nervous system adverse effects. Patients who are given a local anesthetic or no anesthetic should be monitored closely by an anesthesiologist. Monitored anesthesia care consists of monitoring the patient's vital signs and providing sedation as needed. It is often used with procedures such as cataract surgery, pacemaker placement, inguinal hernia repair, and extracorporeal shock wave lithotripsy. Local anesthetics administered epidurally have a faster onset and greater dermatomal spread in elderly persons than in younger persons.
Most general anesthetics are potent myocardial depressants and vasodilators.
Usually, an endotracheal tube is inserted into the patient's airway to control ventilation. Doses of the induction agents etomidate, midazolam, propofol, and thiopental should be significantly lower for elderly patients than for younger patients. Ketamine and etomidate have minimal effects on the cardiovascular system and thus may be the induction agents of choice for the elderly. The volatile anesthetics halothane, enflurane, isoflurane, sevoflurane, and desflurane impair the already attenuated chemoreceptor response in the elderly. The minimal alveolar concentration of these drugs decreases linearly with age, so that a smaller dosage is required to achieve anesthetic levels.