Triple-blind randomized clinical trial of time until sensory change using 1.5% mepivacaine with epinephrine, 0.5% bupivacaine, or an equal mixture of both for infraclavicular block.

BACKGROUND AND OBJECTIVES: Practitioners mix faster-onset, intermediate-duration local anesthetics (LAs) with slower-onset, long-duration LAs to get fast peripheral nerve block (PNB) onset and long duration. We hypothesized that 1.5% mepivacaine (with epinephrine) (mepivacaine) or 1.5% mepivacaine (with epinephrine) mixed with 0.5% bupivacaine (mixed) would reduce PNB sensory onset by 20% or more versus 0.5% bupivacaine alone (bupivacaine). METHODS: Patients (n = 93) having arm surgery were randomized to 1 of the 3 LA groups. Infraclavicular PNB was administered using 1 of 3 LAs; afterward, PNB sensory (motor) onset, duration, and other outcomes were assessed. Subjects, physicians, and the biostatistician were blinded until study completion. RESULTS: Median (interquartile range) PNB sensory onset (in minutes) was as follows: mepivacaine, 3 (3-6); mixed, 6 (3-6); and bupivacaine, 6 (3-12) (P = 0.0085). Mepivacaine PNB sensory onset was not faster than mixed (P = 0.57), but mixed was faster than bupivacaine (P = 0.0035). More mixed group patients achieved PNB sensory onset (0.81) versus the bupivacaine group (0.54) at 6 mins. Median (interquartile range) PNB motor onset (in minutes) was as follows: mepivacaine, 15 (12-18); mixed, 17 (12-21); and bupivacaine, 21 (12-24) (P < 0.0001). Median sensory and motor PNB duration (in minutes) was as follows: mepivacaine, 281 and 320; mixed, 439 and 556; and bupivacaine, 850 and 1109. Sensory (motor) PNB duration was shorter with mepivacaine versus mixed (P < 0.0001, P = 0.034), and mixed was shorter versus bupivacaine (P = 0.0243, P = 0.034). CONCLUSIONS: Mixing 1.5% mepivacaine (with epinephrine) with 0.5% bupivacaine speeds up PNB sensory (motor) onset compared with 0.5% bupivacaine alone.

National incidence of use of monitored anesthesia care.

BACKGROUND: Sedation or monitored anesthesia care (MAC), alone or after peripheral regional nerve block, is currently administered by anesthesiologists and/or certified registered nurse anesthetists. Some of this care may be at risk for substitution by other providers or by reductions in reimbursement. METHODS: Data from the 2006 United States of America National Survey of Ambulatory Surgery were analyzed to determine national rates for the percentage of total ambulatory anesthesia operating room (OR) time that was either (1) sedation and/or MAC, or (2) peripheral regional nerve block with/without sedation or MAC. RESULTS: MAC cases alone comprised 29%± 2% of OR time with an anesthesiologist and/or certified registered nurse anesthetist. MAC and/or peripheral block comprised 34% ± 2% of OR time. Percentages by cases were larger than by OR time (P < 0.0001). Among cases with anesthesia, 42% ± 3% were MAC and 47% ± 2% were MAC with/without peripheral block. Percentages of American Society of Anesthesiologists' Relative Value Guide units for MAC would be intermediate between the 29% and 42%, and for MAC and/or peripheral block between the 34% and 47%. CONCLUSIONS: MAC alone or after peripheral nerve block accounts for a relatively high percentage of ambulatory anesthetics nationwide.

Management by outcomes: efficiency and operational success in the ambulatory surgery center.

Quality of care and service in health care can benefit from the use of algorithm-driven care (standard work) that integrates literature assessment and analysis of local outcome and process data to eliminate unnecessary variation that causes error and waste. Effective management of an ambulatory surgery center requires that leadership emphasize constant improvement in the processes of care to achieve maximum patient safety and satisfaction, delivered with highest efficiency. Process improvement may be achieved by simple measurement alone (the Hawthorne effect). However, as shown in this article, the authors have successfully used the implementation of regular measurement and open discussion of patients' clinical outcomes and other operational metrics to focus active systems improvement projects in ambulatory surgery centers, with excellent results.