Propofol sedation alone or in combination with pharyngeal lidocaine anesthesia for routine upper GI endoscopy: a randomized, double-blind, placebo-controlled, non-inferiority trial.

BACKGROUND: In patients undergoing routine upper EGD, propofol is increasingly used without pharyngeal anesthesia because of its excellent sedative properties. It is unclear whether this practice is non-inferior in regard to ease of endoscopic intubation and patient comfort. OBJECTIVE: To assess the relevance of local pharyngeal anesthesia regarding the ease of EGD performance in patients sedated with propofol as monotherapy. DESIGN: Randomized, double-blind, placebo-controlled, non-inferiority trial. SETTING: One community hospital and one university hospital in Switzerland. PATIENTS: We enrolled 300 consecutive adult patients undergoing elective EGD. INTERVENTION: Pharyngeal anesthesia with 4 squirts of lidocaine spray versus placebo spray immediately before propofol sedation. MAIN OUTCOME MEASUREMENTS: Number of gag reflexes (primary endpoint), number of intubation attempts, and degree of salivation during intubation (secondary endpoints) assessed by the endoscopists and staff. RESULTS: In the lidocaine group, 122 patients (82%) had no gag events, and 25 patients had a total of 39 gag events, whereas in the placebo group 104 patients (71%) had no gag events, and 43 patients had a total of 111 gag events. The rate ratio of gagging with quasi-likelihood estimation of placebo compared with lidocaine was 2.85 (95% confidence interval [CI], 1.42-6.19; P = .005). In adjusted logistic regression analysis, the odds ratio for gagging for placebo pharyngeal anesthesia compared with lidocaine was 1.9 (95% CI, 1.03-3.54). The number of intubation attempts and the degree of salivation were similar in both groups. Two patients in the placebo group experienced oxygen desaturation and needed short-term mask ventilation. LIMITATIONS: The level of sedation and possible long-term side effects of pharyngeal anesthesia were not assessed. CONCLUSION: Topical pharyngeal anesthesia reduces the gag reflex in patients sedated with propofol even though it does not seem to have an influence on the ease of the procedure and on patient or endoscopist satisfaction in adequately sedated patients.

Effect of CCK-1 receptor blockade on ghrelin and PYY secretion in men.

Cholecystokinin (CCK), peptide YY (PYY), and ghrelin have been proposed to act as satiety hormones. CCK and PYY are stimulated during meal intake by the presence of nutrients in the small intestine, especially fat, whereas ghrelin is inhibited by eating. The sequence of events (fat intake followed by fat hydrolysis and CCK release) suggests that this process is crucial for triggering the effects. The aim of this study was therefore to investigate whether CCK mediated the effect of intraduodenal (ID) fat on ghrelin secretion and PYY release via CCK-1 receptors. Thirty-six male volunteers were studied in three consecutive, randomized, double-blind, cross-over studies: 1) 12 subjects received an ID fat infusion with or without 120 mg orlistat, an irreversible inhibitor of gastrointestinal lipases, compared with vehicle; 2) 12 subjects received ID long-chain fatty acids (LCF), ID medium-chain fatty acids (MCF), or ID vehicle; and 3) 12 subjects received ID LCF with and without the CCK-1 receptor antagonist dexloxiglumide (Dexlox) or ID vehicle plus intravenous saline (placebo). ID infusions were given for 180 min. The effects of these treatments on ghrelin concentrations and PYY release were quantified. Plasma hormone concentrations were measured in regular intervals by specific RIA systems. We found the following results. 1) ID fat induced a significant inhibition in ghrelin levels (P < 0.01) and a significant increase in PYY concentrations (P < 0.004). Inhibition of fat hydrolysis by orlistat abolished both effects. 2) LCF significantly inhibited ghrelin levels (P < 0.02) and stimulated PYY release (P < 0.008), whereas MCF were ineffective compared with controls. 3) Dexlox administration abolished the effect of LCF on ghrelin and on PYY. ID fat or LCF significantly stimulated plasma CCK (P < 0.006 and P < 0.004) compared with saline. MCF did not stimulate plasma CCK release. In summary, fat hydrolysis is essential to induce effects on ghrelin and PYY through the generation of LCF, whereas MCF are ineffective. Furthermore, LCF stimulated plasma CCK release, suggesting that peripheral CCK is the mediator of these actions. The CCK-1 receptor antagonist Dexlox abolished the effect of ID LCF, on both ghrelin and PYY. Generation of LCF through hydrolysis of fat is a critical step for fat-induced inhibition of ghrelin and stimulation of PYY in humans; the signal is mediated via CCK release and CCK-1 receptors.