Volume and pH of Gastric Contents in Patients Undergoing Gynecologic Laparoscopic Surgery During Emergence From General Anesthesia

Complications during general anesthesia,induction period: difficult airway, hypotension, upper airway obstruction, laryngospasm, pulmonary aspiration Maintenance period: hypotension, hypertension, awareness, bronchospasm, pulmonary aspiration. Emergence period: delayed emergence, upper airway obstruction, pulmonary aspiration. Pulmonary aspiration occur all ranges of general anesthesia. Because the patients can not protected themselves due to anesthetic medication, example: volatile agent, opioid.This can cause decrease consciousness, delayed gastric emptying time. Incidence of pulmonary aspiration was 1 : 900 - 1 : 10,000 of general of anesthesia (induction 20%, emergence 80%), Anesthesia Service in Siriraj Hospital (2017) 6: 25,000 case Pathophysiology of pulmonary aspiration. Pulmonary aspiration is defined as inhalation of oropharynx or stomach contents through the larynx to low respiratory tract. Aspiration pneumonitis is the inflammation of the lung caused by aspirating or inhaling irritants (Mendelson's syndrome). Gastric acid is a digestive fluid formed in the stomach and is composed of hydrochloric acid, potassium chloride, and sodium chloride.The highest concentration of gastric acid is 140-160 mEq/L. The pH of gastric acid is 1.5-3.5 in the human stomach lumen. Risk factors for increased gastric contents: full stomach, delayed gastric emptying, incompetent lower esophageal sphincter, lithotomy position, laparoscopy, length of surgery more than 2 hr., difficult airway. This study observed Volume and pH of Gastric Contents in Patients undergoing Gynecologic Laparoscopic Surgery during Emergence from General Anesthesia.