Anesthesiology, Healthcare, Medical Education, Pain Medicine, Regional Anesthesiology

Why We Need Acute Pain Medicine Specialists

June 27, 2014 ermariano

Not all pain is the same.

Chronic #pain can be palliated. Acute pain must be stamped out.

Chronic pain can be palliated, but “acute” pain (new onset, often with an identifiable cause) must be stamped out. This requires a systems-based approach led by physicians dedicated to understanding acute pain pathophysiology and investigating new ways to treat it. The solution is definitely not giving more and more opioids.

As our understanding of pain mechanisms has evolved, select physicians have developed a special focus on pain in the acute injury/illness and perioperative settings that has led to the rapid advancement of systemic and site-specific interventions to effectively manage this type of pain. Acute pain medicine involves the routine use of multiple modalities concurrently (i.e., multimodal analgesia) in the in-hospital setting to reduce the intensity of acute pain and minimize the development of debilitating persistent pain, a problem that can result from even common surgical procedures or trauma. Unfortunately, the need for specialists in acute pain medicine is increasing.

The need for physicians who specialize in acute #pain medicine is increasing.

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In December of 2013, I submitted a 161 page letter to the Accreditation Council for Graduate Medical Education (ACGME) requesting that regional anesthesiology and acute pain medicine be considered for fellowship accreditation with the help of my fellowship director colleagues. The Board of Directors of the ACGME informed me this past fall (2014) that they have approved our fellowship to be the next accredited subspecialty within anesthesiology.

Wait – don’t we already have a fellowship program in pain medicine? Yes we do, and this one year post-residency program does include the “Acute Pain Inpatient Experience.” However, this requirement may be satisfied by documented involvement with a minimum of only 50 new patients and is not the primary emphasis of fellowship training in the specialty. Pain medicine is a board-certified subspecialty of anesthesiology, physical medicine and rehabilitation, and psychiatry and neurology; graduates from any of these residency programs can apply to the one year program. In a recent survey study of practicing pain physicians in the United States with added qualification in pain management according to the American Board of Medical Specialties (ABMS), the great majority (83.7%) of respondents defined their practices as following “chronic pain patients longitudinally” (1).

There is clearly room and a need for a subspecialty training program in acute pain medicine that can focus on improving the in-hospital pain experience. Such a program should advance, in a positive and value-added fashion, the present continuum of training in pain medicine.

The Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey is administered to a random sample of patients who have received inpatient care and receive government insurance through Center for Medicare and Medicaid Services (CMS). The survey consists of 32 questions and is intended to assess the “patient experience of care” domain in the value-based purchasing program. A hospital’s survey scores are publicly disclosed and make up 30% of the formula used to determine how much of its diagnosis-related group payment withholding will be paid by CMS at the end of each year. Of the 32 questions, 7 directly or indirectly relate to in-hospital pain management.

Why should acute pain medicine be a subspecialty of anesthesiology? Anesthesiology is a hospital-based medical specialty, and anesthesiologists are physicians who focus on the prevention and treatment of pain for their patients who undergo surgery, suffer trauma, or present for childbirth on a daily basis. For more details on the role of the anesthesiologist, please see “Physicians specializing in the patient experience.” Further, history supports the evolution of acute pain medicine through anesthesiology. The concept of an anesthesiology-led acute pain management service was described first in 1988 (2), but arguably the techniques employed in modern acute pain medicine and regional anesthesiology date back to Gaston Labat’s publication of Regional Anesthesia: its Technic and Clinical Application in 1922, with advancement and refinement of this subspecialty in the 1960s and 1970s (3-7).

By the time they complete the core residency in anesthesiology today, not all trainees have gained sufficient clinical experience to provide optimal care for the complete spectrum of issues experienced by patients suffering from acutely painful conditions, including the ability to reliably provide advanced interventional techniques proven to be effective in managing pain in the acute setting (8-12). We need physician leaders who can run acute pain medicine teams and design systems to provide individualized, comprehensive, and timely pain management for both medical and surgical patients in the hospital, expeditiously managing requests for assistance when pain intensity levels exceed those set forth in quality standards, or to prevent pain intensity from reaching such levels. The mission statement for the Acute Pain Medicine Special Interest Group within the American Academy of Pain Medicine provides additional justification.

In a survey of fellowship graduates and academic chairs published in 2005, 61 of 132 of academic chairs responded (46%), noting that future staffing models for their department will likely include an average of 2 additional faculty trained in regional anesthesiology and acute pain medicine (13).

Currently, there are over 60 institutions in the United States and Canada that list themselves as having non-accredited fellowship training programs focused on regional anesthesiology and acute pain medicine on the ASRA website. Since 2002, the group of regional anesthesiology and acute pain medicine fellowship directors has been meeting twice yearly at the ASRA Spring Annual Meeting and ASA Annual Meeting which takes place in the fall. Despite not being an ACGME-accredited fellowship, this group, recognizing the lack of formalized training guidelines, voluntarily began to develop such guidelines as the foundation for subspecialty fellowship training in existing and future programs. These guidelines were originally published in Regional Anesthesia and Pain Medicine in 2005 (14), then were subsequently reviewed, revised, and published as the 2^nd edition in 2011 (15), and have been recently updated again (16).

As with other subspecialties, acute pain medicine has emerged due to the need for trained specialists—in this case, those who understand the complicated, multi-faceted disease processes of acute pain, and its potential continuity with chronic pain, and can apply appropriate medical and interventional treatment in a timely fashion. The fellowship-trained regional anesthesiologist and acute pain medicine specialist must be capable of collaborating with other healthcare providers in anesthesiology, surgery, medicine, nursing, pharmacy, physical therapy, and more to establish multidisciplinary programs that add value and improve patient care in the hospital setting and beyond.

REFERENCES

Breuer B, Pappagallo M, Tai JY, Portenoy RK: U.S. board-certified pain physician practices: uniformity and census data of their locations. J Pain 2007; 8: 244-50
Ready LB, Oden R, Chadwick HS, Benedetti C, Rooke GA, Caplan R, Wild LM: Development of an anesthesiology-based postoperative pain management service. Anesthesiology 1988; 68: 100-6
Winnie AP, Ramamurthy S, Durrani Z: The inguinal paravascular technic of lumbar plexus anesthesia: the “3-in-1 block”. Anesth Analg 1973; 52: 989-96
Winnie AP, Collins VJ: The Subclavian Perivascular Technique of Brachial Plexus Anesthesia. Anesthesiology 1964; 25: 353-63
Raj PP, Montgomery SJ, Nettles D, Jenkins MT: Infraclavicular brachial plexus block–a new approach. Anesth Analg 1973; 52: 897-904
Raj PP, Parks RI, Watson TD, Jenkins MT: A new single-position supine approach to sciatic-femoral nerve block. Anesth Analg 1975; 54: 489-93
Raj PP, Rosenblatt R, Miller J, Katz RL, Carden E: Dynamics of local-anesthetic compounds in regional anesthesia. Anesth Analg 1977; 56: 110-7
Buvanendran A, Kroin JS: Multimodal analgesia for controlling acute postoperative pain. Curr Opin Anaesthesiol 2009; 22: 588-93
Hebl JR, Dilger JA, Byer DE, Kopp SL, Stevens SR, Pagnano MW, Hanssen AD, Horlocker TT: A pre-emptive multimodal pathway featuring peripheral nerve block improves perioperative outcomes after major orthopedic surgery. Reg Anesth Pain Med 2008; 33: 510-7
Jin F, Chung F: Multimodal analgesia for postoperative pain control. J Clin Anesth 2001; 13: 524-39
Kehlet H, Dahl JB: The value of “multimodal” or “balanced analgesia” in postoperative pain treatment. Anesth Analg 1993; 77: 1048-56
Young A, Buvanendran A: Recent advances in multimodal analgesia. Anesthesiol Clin 2012; 30: 91-100
Neal JM, Kopacz DJ, Liguori GA, Beckman JD, Hargett MJ: The training and careers of regional anesthesia fellows–1983-2002. Reg Anesth Pain Med 2005; 30: 226-32
Hargett MJ, Beckman JD, Liguori GA, Neal JM: Guidelines for regional anesthesia fellowship training. Reg Anesth Pain Med 2005; 30: 218-25
Guidelines for fellowship training in Regional Anesthesiology and Acute Pain Medicine: Second Edition, 2010. Reg Anesth Pain Med 2011; 36: 282-8
Guidelines for fellowship training in Regional Anesthesiology and Acute Pain Medicine: Third Edition, 2014. Reg Anesth Pain Med 2015; 40: 213-7

CME, Medical Education, Pain Medicine

ASRA Comes to San Francisco!

June 19, 2014 ermariano

This year’s American Society of Regional Anesthesia and Pain Medicine’s 13th Annual Fall Pain Medicine meeting happens to be in my “neck of the woods”—one of the greatest cities in the world—San Francisco, California. Here are a few things you may or may not have known about San Francisco.

San Francisco is the biggest little city. At just under 47 square miles and with more than 200,000 inhabitants, San Francisco is second only to New York City in terms of population density. Despite its relatively small size, “the City” (as we suburbanites refer to it) consists of many small neighborhoods, each with its own charm and character: Union Square, the Financial District, Pacific Heights, the Marina, Haight-Ashbury, Chinatown, Little Italy, Nob Hill, Russian Hill, SoMa (South of Market), the Fillmore, Japantown, Mission District, Noe Valley, Twin Peaks, Castro, Sunset, Tenderloin, and others. For this reason, San Francisco may arguably be the only option for die-hard New Yorkers who wish to relocate away from snow.

Even though it doesn’t snow, San Francisco weather is incredibly unpredictable, even when going from one side of the city to the other. “The coldest winter I ever spent was a summer in San Francisco,” a quote often mistakenly attributed to Mark Twain (no one really knows who actually said it), is nevertheless often true. Here in the San Francisco Bay Area, our local meteorologists provide daily forecasts for each of the region’s microclimates. The western side of the City along California’s coast is regularly plagued with fog while the eastern side of the City tends to be sunny most days of the year. It’s always a good idea to check the microclimate forecast before heading over to see the Golden Gate Bridge just in case it happens to be shrouded in fog. Also, average July temperatures in the City range in the 50s-60s Fahrenheit (no different than average November temperatures), so summer tourists often contribute to the local economy by buying “SF” logo sweatshirts for their walk across the City’s most famous bridge.

San Francisco is very family-friendly. If you’re debating whether or not to make a family trip out of the Fall Pain Meeting, my advice is to do it. Right around the conference hotel, the Hyatt Regency San Francisco, there are a number of attractions and events worth checking out. Every Saturday there is a huge farmers market at the Ferry Building across the street from the hotel. As you probably figured out, from the Ferry Building you can also take a ferry ride to a number of other destinations in the Bay Area (I recommend Sausalito, a short trip that takes you past Alcatraz). For kids, there are 3 parks within walking distance, the San Francisco Railway Museum, Exploratorium, and the cable car turnabout at Powell and Market Street; trips to Fisherman’s Wharf or the aquarium are a short taxi or cable car ride away. In addition, runners will love running up and down the Embarcadero which gives you a view of the Bay Bridge and takes you past the City’s many piers; shoppers will be in heaven; and foodies have an impossible decision to make when choosing the location for every meal (try Slanted Door at the Ferry Building at least once).

Enough about San Francisco—you’ll have to see it for yourself. To register for the Fall Pain Medicine meeting, visit http://www.asrameetings.com/. For an overview of scheduled events in the words of meeting Chair, Dr. David Provenzano, see the August 2014 issue of ASRA News. This issue also includes fantastic original content covering the topics of digital subtraction angiography, pain outcomes, ASRA’s first entry into the app market, and much more!

Anesthesiology, Healthcare, Knee Replacement, Medical Education, Outcomes Research, Pain Medicine, Patient Safety, Regional Anesthesiology

Regional Anesthesia & Rehabilitation Outcomes after Knee Replacement

June 6, 2014 ermariano

Among Medicare beneficiaries in the United States, the number of primary total knee arthroplasty (TKA) procedures from 1991 to 2010 increased by 161.5% (1). Postoperative pain remains one of patients’ top concerns when undergoing elective surgery (2) and can limit patients’ functional ability in the early postoperative period (3). Providing effective perioperative pain control has potential longer-term implications since early rehabilitation may lead to improvements in functional outcomes later on (4). With the ability to select specific targets for local anesthetic injection and infusion, regional anesthesia techniques, neuraxial and peripheral, are commonly included in the perioperative analgesic protocol for joint arthroplasty patients (5-11). While the data supporting the analgesic efficacy of regional anesthesia techniques in this setting are strongly positive, studies attempting to attribute functional outcome benefits to regional anesthesia demonstrate mixed results.

The main challenge in assessing functional outcomes following joint replacement is the selection of outcomes; these can be divided into performance-based outcomes and self-reported outcomes (12, 13). Performance-based outcomes are measurable and arguably more objective, although often subject to effort. Examples of these outcomes and their units of measure include joint range of motion in degrees (e.g., flexion, extension, rotation); timed walking tests in meters (e.g., 6 minute walking test [6MWT], 2 minute walking test [2MWT]); muscle strength in units of force using a dynamometer (e.g., maximum voluntary isometric contraction [MVIC]); and timed up-and-go (TUG) in minutes (12, 13). Self-reported outcomes are typically survey-based; examples include the Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Knee Society Score, and Lower Extremity Functional Scale (12, 13). Since patient perception of successful rehabilitation is an important factor, self-reported outcomes should be reported with performance-based outcomes (12)^. Another important challenge when measuring and comparing functional outcomes is that clinical pathways for joint arthroplasty that integrate pain management (including regional analgesia), physical therapy, nursing, and surgical care are often specific to individual institutions, and institutions may vary with respect to rehabilitation goals and the timeline to achieve them.

Epidural Analgesia

Epidural analgesia has been used for perioperative pain management in joint replacement patients since at least the 1980s (14, 15). In 1987, Raj and colleagues compared postoperative systemic opioid analgesia to continuous epidural analgesia (bupivacaine 0.25% at 6-15 ml/hr) for TKA patients in a prospective non-randomized study (14). Although pain scores were lower in the epidural group, not surprisingly a high proportion of these patients experienced complete motor block of the lower extremities; although the authors mention “rigorous passive exercises,” specific rehabilitation outcomes were not reported (14). Later studies have reported functional benefits associated with continuous epidural analgesia, such as shorter time to achieve ambulation distance and range of motion goals, when compared to parenteral opioids alone (16). At institutions where continuous epidural analgesia is currently employed as part of a multimodal analgesic protocol, very low doses of local anesthetic (e.g., 0.06% bupivacaine) in combination with opioid are used in order to minimize motor block (17).

Peripheral Nerve Blocks

The innervation of the knee is complex and involves contributions from both the lumbar and sacral plexuses. While epidural analgesia is effective, it is also associated with clinically-significant side effects (e.g., nausea/vomiting and motor block of the non-operative limb) (5, 18) and the potential for neuraxial hematoma in patients on pharmacologic thromboprophylaxis (19). Thus, peripheral nerve block options, either single-injection or continuous infusions, have been explored for postoperative pain management.

Two early studies by Capdevila (6) and Singelyn (20) have shown continuous femoral nerve block (FNB) to provide comparable analgesia and physical therapy outcome achievement with fewer side effects when compared to epidural analgesia. Both of these studies also demonstrated shorter hospital length of stay for the regional anesthesia groups compared to an opioid-only group (6, 20), but hospitalization duration for these studies was, on average, greater than what has been reported in other studies (21). Triple-masked, placebo-controlled randomized clinical trials have shown that CPNB can shorten the time to achieve discharge criteria, including 100 m ambulation distance, for TKA (10, 22) and total hip arthroplasty (THA) (9) patients, but actual hospital duration was similar in these studies.

One of the interesting findings from the Singelyn study was that regional anesthesia patients maintained a knee flexion advantage over the opioid-only group at 6 week follow-up (20); although this advantage did not remain at 3 months, this finding supported the potential for long-term functional improvement resulting from effective pain management and early rehabilitation in the immediate perioperative period (4). In a randomized comparison of continuous FNB to local infiltration analgesia (LIA) for TKA, the FNB group spent more time out of bed walking; at 6 weeks, the FNB group showed more improvement in performance-based (6MWT) and self-reported functional outcome assessments (23). In contrast, the one year follow-up studies of randomized clinical trial subjects (9, 10, 22) using self-reported outcome measures for functional status (WOMAC) did not show long-term improvement associated with regional anesthesia techniques (24-27).

The rehabilitation outcome measured in the immediate postoperative period that correlates best with long-term functional improvement is not yet established. Ambulation distance is often measured by physical therapists and included in discharge criteria (9, 10, 22). For institutions that emphasize ambulation in their clinical pathway for lower extremity joint arthroplasty, a major concern raised with regard to FNBs is the potential association with increased fall risk (28, 29) although a recent large database study disputes this finding. In-hospital falls can lead to prolonged hospital stays with higher costs and are associated with more frequent postoperative complications, including serious organ system dysfunction and death (30). With currently-available local anesthetic solutions and typical doses, perineural infusion does produce clinically-significant quadriceps weakness when administered near the femoral nerve or lumbar plexus (31, 32). Since the local anesthetics themselves cannot select sensory over motor nerves( 33), anesthesiologists have started exploring alternate nerve block locations to minimize the risk of motor block and maximize patient rehabilitation.

From Workman JJ, et al. Presented at 2013 ASRA Spring Annual Meeting

For TKA, a more distal nerve block location in the adductor canal can provide effective analgesia postoperatively (34) and has been shown to better preserve quadriceps strength compared to a FNB in both volunteers (35) and clinical patients (11). Regional analgesic techniques are only one part of the overall pain management plan. While they are often included in multimodal analgesic protocols along with non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, and low-dose opioids (36), there is a growing body of evidence to support the adductor canal block as the regional analgesic technique of choice for promoting postoperative ambulation within a clinical pathway (37, 38).

For patient information with answers to frequently-asked questions about regional anesthesia, please see “Regional Anesthesia FAQs.”

References

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Capdevila X, Barthelet Y, Biboulet P, Ryckwaert Y, Rubenovitch J, d’Athis F. Effects of perioperative analgesic technique on the surgical outcome and duration of rehabilitation after major knee surgery. Anesthesiology. Jul 1999;91(1):8-15.
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Ilfeld BM, Le LT, Meyer RS, et al. Ambulatory continuous femoral nerve blocks decrease time to discharge readiness after tricompartment total knee arthroplasty: a randomized, triple-masked, placebo-controlled study. Anesthesiology. Apr 2008;108(4):703-713.
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