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The development of ambulatory surgery and that of peripheral nerve
blocks (PNBs) occurred over two separate historic timelines. The performance
of outpatient or ambulatory surgeries commenced in the mid-1800s, and its
utilization rapidly escalated throughout the next century. By 1980, 16.3%
of all surgeries were performed on an outpatient basis. By 1984 this number
rose to 30% and the Society for Ambulatory Anesthesia (SAMBA) was born.
The total outpatient rate approached 50% by 1990, 60% in 1997, and may
have hit 70% in 2003.1,2 During the same span of time,
techniques for PNBs were also being discovered. The decades from 1884, (when
Koller and Brettauer first instilled ocular cocaine in Heidelberg,
Germany3) to 1912 and 1914, (when Kappis and Heidenhein
described the interscalene block,4) marked the birth of
PNBs. Despite the coexistence of both ambulatory anesthesia and PNB
techniques for over a century, they were not typically used concurrently.
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As ambulatory surgery acquired today's popularity and widespread use,
the scope of surgical procedures similarly expanded to become more invasive
and pain-inducing. Suddenly, physicians were faced with a dual challenge:
provide short-acting anesthesia thus achieving home-readiness within hours
of surgery, concurrent with long-acting postoperative analgesia permitting
the patient to remain discharged to the home environment. The differences
between these dual desires have proven irreconcilable with modern opiate
analgesia. This has been recently documented by Apfelbaum and colleagues,
who quantified the shortcomings of ambulatory analgesic regimens. They found
that 78% of those queried had felt pain of moderate (52%), severe
(22%) or extreme (7%) intensity.5
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In response to ambulatory anesthesia's dilemma, PNB techniques offer
solutions ideal for an outpatient anesthetic: site-specific surgical
anesthesia and a decreased dependency on general anesthesia (GA). In so
doing, PNBs buffer the response to surgical stress, better maintain
functional residual capacity, defend against loss of immunologic function,
and avoid or shorten the period of postoperative ileus.6
By providing effective analgesia, PNBs can reduce patient exposure to
opioids and their side effects. This allows for a more rapid discharge of
satisfied patients to their home environment, resulting in cost savings for
the ambulatory surgery center. As a cornerstone of multimodal analgesia,
PNBs with long-acting local anesthetic (LA) help reduce patient readmission
for pain or other side effects. Extending the effect of LA through
continuous peripheral nerve blocks (CPNBs) further lengthens the period of
low side-effect postoperative analgesia in the home environment.
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Despite the advances in PNBs and CPNBs, these techniques remain
underutilized skills in ambulatory anesthesia. As recently as the year 2000,
Dexter and Macario7 revealed that ambulatory surgeries
utilized regional anesthesia in only 8% of cases. A 1997 survey by Hadzic
and coworkers found that although 98% of anesthesiologists used some
regional techniques, less than half of respondents placed at least five PNBs
per month.8 A 2001 survey by Klein and colleagues
concurred that although interscalene, axillary, and ankle blocks were
performed more often, ...