Intravenous lidocaine decreased oxygen-desaturation episodes induced by propofol-based sedation for gastrointestinal endoscopy procedures: a prospective, randomized, controlled trial

The Emerging Evidence

A lidocaine induction dose followed by infusion can reduce propofol requirements, leading to decreased desaturation episodes, coughing, involuntary movement, and improved endoscopist satisfaction

Fast Facts

• Lidocaine Dose: 1.5 mg/kg bolus + 4 mg/kg/h infusion (well within safety guidelines).
• Safety: No lidocaine-related side effects (e.g., numbness, tinnitus, or anaphylaxis) were reported.
• Study Design: 322 patients in a double-blind, randomized, placebo-controlled trial.
• Oxygen-desaturation episodes (ODE) defined with occurrence of SpO₂ < 90% for more than 10 s after induction
• Subclinical respiratory depression defined as 90% ≤ SpO₂ < 95% for more than 15 s, improved using jaw-thrust maneuver

Why It Works

• Airway Protection: Lidocaine enhances ventilatory response to carbon dioxide, stabilizing respiratory function during sedation.
• Anti-Inflammatory Action: Lidocaine’s opioid-sparing and anti-inflammatory effects contribute to smoother recoveries.
• Propofol Reduction: By reducing propofol dosage, lidocaine lowers the risk of hypoxia and circulatory complications.

Key Takeaways

Reduced Risk of Hypoxia

• ODE incidence: 22% in the lidocaine group vs. 39% in the control group (P=0.009).
• Severe hypoxia was rare, with only 1% of patients affected in both groups.

Minimized Adverse Events

• Coughing: 11% in the control group vs. 1% with lidocaine (P=0.001).
• Involuntary movements: 14% in the lidocaine group vs. 26% in the control group (P=0.013).

Enhanced Provider and Patient Experience

• Endoscopist satisfaction: 83% in the lidocaine group rated 10/10, compared to 67% in the control group (P=0.001).

Propofol Sparing Effect

• Lidocaine significantly reduces propofol requirements, minimizing sedation-related risks like respiratory depression.

Excerpts

Limb movement, respiratory depression and cardiovascular events often occur in patients undergoing PSA (procedure sedation and anesthesia), especially in the combined examination of gastroscopy and colonoscopy, due to the longer operation time and stronger stimulation.

hypoxemia commonly occurs during propofol sedation due to respiratory depression and shared channels with gastroscopy

propofol consumption, aging, high body mass index (BMI), sleep apnea syndrome, and operation time were independent risk factors for hypoxia

adjuvant drugs with less side effects on cardiovascular function, while reducing the dosage of propofol...For example, opioids and benzodiazepines used with propofol can significantly decrease propofol requirements, but hypoxemia and hypotension still frequently occur

Possessing some properties, such as increasing ventilatory response to carbon dioxide (CO₂) and anti-nociceptive action, intraoperative application of IV lidocaine can reduce the dosage of propofol, prevent postoperative coughing and sore throat in adults

incidence of ODE was 22% (32/147 cases) in the Lidocaine group and 39% (59/153 cases) in the Control group (difference, −16.7%, P = 0.009). According to definitions of different degree of hypoxic, there were 19 (13%) cases happened subclinical respiratory depression in Lidocaine group and 17 cases (11%) in Control group. In Lidocaine group, 30 patients (20%) developed hypoxia and 2 patients (1%) happened severe hypoxia, whereas 56 patients (37%) occurred hypoxia and 3 patients (1%) occurred severe hypoxia in the Control group, P = 0.017

17 cases (11%) experienced coughing in the control group, whereas only 2 patients in the Lidocaine group, P = 0.001. The incidence of involuntary body movements was lower in Lidocaine group than that in the control group (Lidocaine vs Control: 14% vs 26%, P = 0.013)

proportion of endoscopists with a satisfaction score of 10 points in the lidocaine group was higher than that in the control group (lidocaine vs control: 83% vs 67%, P = 0.001).

A large amount of evidence confirms that IV lidocaine has anti-inflammatory, opioid protective effects, the ventilatory response to carbon dioxide, and the combination of these features leads to a series of effects, such as reducing postoperative pain and opioid consumption, shortening the duration of digestive intestinal obstruction, and producing significant propofol sparing, finally reducing the incidence of ODE.

no lidocaine related side effect such as tongue numbness, metallic taste, tinnitus, anaphylaxis, appeared among the two groups.

Abstract

Background: As a popularly used analgesic adjuvant, intravenous (IV) lidocaine could reduce the consumption of propofol in painless gastrointestinal (GI) endoscopy. However, whether IV lidocaine could affect the incidence of oxygen-desaturation episodes (ODE) during painless GI endoscopy is still unknown. Therefore, we tested the hypothesis that IV lidocaine could decrease the incidence of propofol-induced ODE and involuntary movements in patients during GI endoscopy.

Methods: Three hundred twenty-two patients scheduled for GI endoscopy were randomly divided into lidocaine group and control group. After midazolam and sufentanil injection, a bolus of 1.5 mg/kg lidocaine was given and followed by continuous infusion of 4 mg/kg/h in lidocaine group, whereas the same volumes of saline solution in control group. Then, propofol was titrated to produce unconsciousness. The primary outcome was the incidence of ODE during the procedure. The secondary outcomes were the incidence of different degree of hypoxia and corresponding treatments and the involuntary body movements.

Results: A total of 300 patients were finally included in the analysis, 147 patients in lidocaine group and 153 in control group. The incidence of ODE was 22% in lidocaine group and 39% in control group (OR:0.052; 95%CI: 0.284–0.889; P = 0.018). IV lidocaine also improved the occurrence of different degree of hypoxia (P = 0.017) and needed few treatments (P = 0.028). The incidence of involuntary body movements (14% vs 26%, P = 0.013) and adverse circulatory events was decreased by IV lidocaine.

Conclusions: IV lidocaine adjuvant to propofol-based sedation could reduce the incidence of oxygen-desaturation episodes and involuntary body movements, with fewer adverse circulatory events.

Citation

Qi XR, Sun JY, An LX, Zhang K, Xue FS. Effects of intravenous lidocaine on hypoxemia induced by propofol-based sedation for gastrointestinal endoscopy procedures: study protocol for a prospective, randomized, controlled trial. Trials. 2022 Sep 24;23(1):800. doi: 10.1186/s13063-022-06719-6. PMID: 36153625; PMCID: PMC9509543.

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