Tag Archives: analgesia

Best Of AAST 2021: Liposomal Bupivacaine For Rib Fractures

The mainstays of rib fracture management are pain control and pulmonary toilet. The pain part of the equation can be managed in many ways, using topical, oral, IV, and injectable medications.

Rib blocks have been a mainstay for achieving some degree of local pain control. Classically, xylocaine was injected in the area around the costal nerve at or proximal to the fracture site. Then we found that if we combined the anesthetic agent with epinephrine, we could prolong the effect. New, longer-acting agents came around, and we could achieve a longer duration of action.

Then there is the new kid on the block: liposomal bupivacaine, also known as Exparel in the US.  The manufacturer was able to take molecules of bupivacaine and encapsulate them in a lipid membrane. When injected, these little liposomes slowly release their cargo, with a more prolonged anesthetic effect. Allegedly.

Sounds great! But does it work? The group at University of Cincinnati designed a prospective, double-blinded, randomized placebo control study of liposomal bupivacaine vs saline injection for pain control in up to six rib fractures. Subjects had significant injury as measured by their inability to achieve at least 50% of the desired inspiratory capacity. The authors monitored a number of respiratory parameters, as well as the pain score.

Here are the factoids:

  • Two cohorts of 50 patients were recruited, one received liposomal bupivacaine in up to six rib fractures, and the other received saline injections
  • The bupivacaine group achieved higher incentive spirometry volumes over the first two days, by about 200 cc
  • There was no change in daily pain scores in either group
  • Both groups showed a similar decrease in opioid use over time
  • Hospital and ICU lengths of stay were the same, and there were no complications or adverse events

Bottom line: Hmm. What’s going on here? There is a moderate amount of literature out there that does indicate a positive effect from liposomal bupivacaine in other conditions. But there are also some blinded, randomized studies that fail as well. So there are three possibilities:

  1. Liposomal bupivacaine isn’t a panacea, and works better in some situations than others
  2. This study failed to show a real difference for some reason
  3. A combination of both

This is a relatively small study, and the authors were not able to share their power analysis. They did not state if the spirometry volumes were significantly different, although I’m not sure 200 cc is clinically relevant. Maybe. But pain scores remained similar and opioid use declined as expected in both. 

These kinds of studies can be important. The difference in cost between injecting liposomal bupivacaine ($19 / ml) vs regular bupivacaine (10 cents / ml) vs saline/nothing (free) is striking. The premium price for the liposomal form needs to have a clear benefit or a cheaper product should be used.

Here are my questions for the presenter and authors:

  • Was your study big enough to show a result? Show us your power analysis.
  • How significant was the incentive spirometry result. Was the difference clinically noticeable?
  • What is your takeaway for this study? Your conclusion parrots the results. What will you do differently now, if anything?

Reference: INTERCOSTAL LIPOSOMAL BUPIVACAINE INJECTION FOR
RIB FRACTURES. AAST 2021, Oral abstract #20.

The Next Best Postop Analgesia – Ice Packs?

As usual, the simplest things are often the best. A recent paper looked at the newest and greatest “drug” to use for providing postoperative analgesia: the good, old-fashioned ice pack!

This concept is obviously not new. Cold is known to quiet inflammation, which is inevitable when tissues are incised. Athletes and their trainers have used ice packs forever. Surgical studies have evaluated their use in orthopedic extremity procedures as well as hernia repairs.

The current paper, from several surgical departments at Emory in Atlanta, randomly allocated patients to have an ice pack placed on their laparotomy incision. Only patients undergoing open abdominal procedures were included. Ice packs were maintained in place for 24 hours, and were then allowed as long as the patient wanted it. Pain, as judged by the analog pain scale, narcotic use, and hospital length of stay were measured. A power analysis was actually performed, and the number of patients required to detect a 15% difference were enrolled (!).

Here are the factoids:

  • 55 patients were enrolled, and were truly randomized
  • Most operations were for pancreatic, gastric, liver, and colorectal cancers
  • The usual demographics of the two groups were identical
  • Pain score was decreased as measured twice later in the day on day 1, and once on day 3
  • Narcotic use was lower on day 1
  • Length of stay was the same for both groups
  • Patients in the cryotherapy group requested to keep the ice packs for an average 2.75 days. None requested removal at the end of day 1.
  • Most stated that they would request an ice pack the next time they had surgery

Bottom line: For once, a nicely done study! Simple and to the point. It reinforces the concept that cheap and simple can still be good. The ice packs in this study were plain old refillable bags filled with ice cubes, not fancy gel or chemical packs that cost lots of money. And the decrease in narcotic use is huge! The side effects of these drugs (constipation, urinary retention, allergic reaction, etc.) create the need for interventions that introduce another whole world of complications.

Consider adding the simple old ice pack to your armamentarium of postop pain relief. But remember, you’ve got to start it as early as possible for best effect, ideally as the surgical dressing is placed.

Related posts:

Reference: Ice Packs Reduce Postoperative Midline Incision Pain and Narcotic Use: A Randomized Controlled Trial. JACS 10.1016/j.jamcollsurg.2014.03.057, 2014.

Prehospital Attitudes About Analgesia

Pain relief is important for two reasons: it’s the humane thing to do for someone who is suffering, and just as importantly, it assists in the physiologic response to trauma. There are several papers that have shown that prehospital providers may not use pain medications as much as they should. Why would this be?

Researchers at Yale released a paper describing a number of interviews with prehospital providers to get the answers to this question. They did individual and group interviews with five EMS agencies in the states of New Hampshire, Massachusetts and Connecticut. Eight individual and 2 group interviews were conducted, with a total of 15 paramedics in the study.

The results were very interesting and several themes emerged:

  • There was a reluctance to give opioids unless objective signs were present (deformity, hypertension)
  • There was a preoccupation that patients might be malingering
  • Paramedics were not clear on what the pain control target should be (complete relief vs “taking the edge off”)
  • Fear of masking symptoms with pain medicine
  • Reluctance to use large doses (e.g. using no more than 5mg morphine)

Bottom line: This study is very small, which is a problem. But it also used face to face interviews, so a lot of information was obtained. It’s hard to say if this work is representative of other agencies or countries, but it is thought provoking. My take is this: trauma hurts like hell. Patients really do need the medication. And they are not going to get addicted from a few doses while enroute to the hospital. Whether the cause of their injury was truly accidental or the result of poor choices, it’s not our place to judge because we don’t know the full story. Give pain medication and be generous. You’re not going to make the symptoms go away. But do use judgment to make sure they keep breathing all the way to the emergency department.

I’m very interested in EMS comments about this study. Please comment or tweet!

Reference: Paramedic attitudes regarding prehospital analgesia. Prehospital emergency care; Online ahead of print, Sep 2012.

Prehospital Attitudes About Analgesia

Pain relief is important for two reasons: it’s the humane thing to do for someone who is suffering, and just as importantly, it assists in the physiologic response to trauma. There are several papers that have shown that prehospital providers may not use pain medications as much as they should. Why would this be?

Researchers at Yale released a paper describing a number of interviews with prehospital providers to get the answers to this question. They did individual and group interviews with five EMS agencies in the states of New Hampshire, Massachusetts and Connecticut. Eight individual and 2 group interviews were conducted, with a total of 15 paramedics in the study.

The results were very interesting and several themes emerged:

  • There was a reluctance to give opioids unless objective signs were present (deformity, hypertension)
  • There was a preoccupation that patients might be malingering
  • Paramedics were not clear on what the pain control target should be (complete relief vs “taking the edge off”)
  • Fear of masking symptoms with pain medicine
  • Reluctance to use large doses (e.g. using no more than 5mg morphine)

Bottom line: This study is very small, which is a problem. But it also used face to face interviews, so a lot of information was obtained. It’s hard to say if this work is representative of other agencies or countries, but it is thought provoking. My take is this: trauma hurts like hell. Patients really do need the medication. And they are not going to get addicted from a few doses while enroute to the hospital. Whether the cause of their injury was truly accidental or the result of poor choices, it’s not our place to judge because we don’t know the full story. Give pain medication and be generous. You’re not going to make the symptoms go away. But do use judgment to make sure they keep breathing all the way to the emergency department.

I’m very interested in EMS comments about this study. Please comment or tweet!

Reference: Paramedic attitudes regarding prehospital analgesia. Prehospital emergency care; Online ahead of print, Sep 2012.

Trauma 20 Years Ago: Continuous Epidural Analgesia for Rib Fractures

Rib fractures are painful, and lots of rib fractures not only hurt, but can lead to complications or death. We take for granted all the modalities we now have for pain relief with rib fractures:

  • IV narcotics
  • epidural analgesia
  • rib blocks
  • intrapleural analgesia
  • lidocaine patches
  • fracture fixation techniques
  • and more!

In April 1991, we were still trying to figure out if epidural analgesia was any better than IV narcotics. A small prospective study of 32 patients who were awake and alert and had at least 3 rib fractures were given either IV or epidural fentanyl. The drug was administered as an initial bolus, followed by a continuous infusion. A visual analog pain scale was used for titration.

Vital capacity increased significantly in both groups. Epidural analgesia also led to an improvement in maximum inspiratory pressure (which we now know as NIF). IV analgesia led to somewhat troubling increases in pCO2 and decreases in pO2, whereas epidural administration did not. Pain relief was better with the epidural, while side effects were similar.

The authors concluded that epidural analgesia offers several advantages over IV, and stated that it should be the preferred method for patients at high risk for complications following multiple rib fractures. This paper started us on the path to using the epidural for pain management with significant rib fractures.

Reference: Prospective evaluation of epidural and intravenous administration of fentanyl for pain control and restoration of ventilatory function following multiple rib fractures. J Trauma 31(4):443-451, 1991.