Precision sedation with novel single syringe multimodal opioid or non-opioid 6-2-2 mixtures.

Abstract

Objectives: The purpose of this study is to determine the efficacy and safety of sedation/analgesia using mixtures of propofol, opioids or non-opioid sedatives, and lidocaine or etomidate in one single syringe.

Design: A retrospective case review was undertaken.

Setting: University outpatient surgical center.

Patients: 1,376 adult patients undergoing ophthalmic surgery with ocular blocks and monitored anesthesia care were studied.

Intervention: The 6 opioid-based mixtures contained 6 portions of propofol, 2 portions of opioid (alfentanil, fentanyl, a combination of alfentanil and fentanyl, or alfentanil and hydromorphone), and 2 portions of lidocaine or ketamine in a single syringe, in a 6:2:2 volume ratio. The non-opioid mixture contained 6 portions of propofol, 2 portions of ketamine, and 2 portions of etomidate. A bolus dose for all mixtures was calculated based on the patient's age and weight: < 40 yr, 1.2 mL/10 kg; 40-59 yr, 1 mL/10 kg; 60-69 yr, 0.8 mL/10 kg; 70-84 yr, 0.6 mL/10 kg; ≥85 yr, 0.5 mL/10 kg, and delivered by hand push or infusion pump intravenously (IV). For patients with a body mass index (BMI) >25, the adjusted weight for dosing (AWFD) was used: AWFD = ideal body weight (IBW) + 0.3 x (Actual weight [AW] - IBW). Ocular blocks were performed when patients reached a moderate level of sedation. Blood pressure (BP), heart rate (HR), oxygen saturation, clinical signs of sedation, responses to blocks, apnea and need for airway support, and recall were recorded.

Measurement and main results: 91 %-98 % of all patients had no pain during ocular blocks and 98-99 % had no head movement, except in the KE6-2-2 without K10 (bolus only) group. The readiness time was 46-51 s for the opioid groups and 36- 43 s for the non-opioid groups. In the opioid groups, 97 %-99 % had no apnea and 88 %-94 % had no oxygen desaturation, while 99 % had no apnea and 96 % had no oxygen desaturation in the non-opioid groups. Heart rate and blood pressure decreased <10 % in the opioid groups while there was nearly no change in the non-opioid groups.

Conclusion: Adjusted for age and weight, the bolus dose of the 6-2-2 mixture met the sedation requirements for ocular blocks in most patients with favorable outcomes and minimal airway or hemodynamic compromise regardless of which mixture was used.