The aging digestive tract: what should anesthesiologists know about it?

At present, elderly individuals represent approximately 18.5% of the European population and account for about 23% of surgical procedures performed. This patient population is at a higher risk for perioperative complications and adverse postoperative outcome. This narrative review highlights our current knowledge about physiological changes in the aging gut and the implications for anesthesiologists. The reduced response to stimuli in the pharynx, and reduction of the cough reflex that occurs in many older individuals, probably explains the increased incidence of aspiration pneumonia that occurs in the elderly. These changes also increase the risk for aspiration during anesthesia. Aging affects the clearance of fluids and solids in the esophagus, associated with a higher incidence of gastro-esophageal reflux disease. Healthy aging appears to be associated with modest slowing of gastric emptying, but this does not demand prolonged preoperative fasting. The physiological changes associated with polypharmacy also make elderly patients a risk group for pulmonary aspiration during anesthesia. Further research is needed to determine the effects of commonly used anesthetic agents on the pharyngo-gastrointestinal tract in elderly patients.