A study led by doctors at the Medical University of South Carolina and UMass Chan Medical School found that ultrasound-guided nerve blocks helped kids with broken thigh bones, also known as femurs, feel less pain and need fewer systemic medications than children who didn't get the injections.
One of those physicians, Matthew Moake, M.D., Ph.D., is an ultrasound specialist and an associate professor of pediatric emergency medicine at MUSC. He also works in the Emergency Department of the MUSC Shawn Jenkins Children's Hospital.
"There's a big push to avoid systemic stuff," he said, referring to narcotic medications such as fentanyl and morphine that affect the whole body and have been shown to have both short- and long-term complications.
"The nerve block, which is basically injecting local anesthetic, lets us really decrease the use of systemic medications and their side effects in the short and long term. It also gives you more customized care," he said. "The nerve block doesn't have any effect anywhere but the leg down."
Measuring children's pain
The study included 114 children aged 4 to 17. They came to emergency departments in 12 health care centers in the U.S. and Australia, including the MUSC Shawn Jenkins Children's Hospital in Charleston.
The children started with similar self-reported levels of pain from their fractured femurs. The study used the revised six-point Faces Pain Scale to measure that pain.
Each face is associated with an even number from zero to ten, with ten meaning the pain is at its worst. The kids pick a face to match how they're feeling. The researchers turn those choices into numbers they can analyze.
Then, an hour after the kids joined the study, their pain was re-measured. Moake said kids who got fascia iliaca compartment nerve blocks, which targeted tissue through which hip and leg nerves pass, had higher reductions in pain than kids who didn't get the blocks. There was a 3.8 reduction for the first group compared with 0.8 for the second.
Lasting effect?
The researchers also wanted to know if the greater reduction in pain would last beyond 60 minutes. So three hours later, the kids' pain level was measured for a third time. Of the 87 children who still had documented pain scores, the kids who had the nerve blocks once again had a bigger reduction in pain levels than kids in the non-nerve block group – 3.6 compared with 1.7.
"Taking pain down by three or four points on a scale, the kids are going from unbearable pain to pain they could deal with. And you maybe add ibuprofen or Tylenol, and they can be comfortable enough to have a conversation and not be completely sedated by systemic opioids. And with that you get faster recovery, which is great," Moake said.
Striking example
He gave an example. "One kid we did the nerve block on slept through the full X-rays. We managed to pull him into traction, where we put tension on the leg to try to pull the bones in line. It can be a very painful experience. And he basically opened his eyes and sat up briefly and then went right back to sleep as we did that to him. The parents were just in shock."
Reduced opioid medications
Another key finding involved a reduction in opioid use for pain management. The difference between the two groups of kids with broken femurs was striking, Moake said. "The nerve block patients received 73% fewer oral morphine equivalents than the non-block children."
His team noted that reducing opioid exposure early in life may lower the lifetime risk of dependency on and addiction to opioids.
Study conditions
The study team had no control over which treatments the children got. That was determined by the children's medical teams, which followed hospital policies.
And it didn't matter if the kids in the study got opioids, sedatives, muscle relaxants or nerve blocks – they were still qualified to participate. The difference was that kids who got nerve blocks were put into one group for research purposes and the kids who didn't into another.
Study medications and ultrasounds
The medications and ultrasounds used in the study were also an important part of its design.
The study focused on the medications ropivacaine and bupivacaine, which work similarly and provide long-acting pain control. Neither is an opioid.
The study also looked at the importance of using ultrasounds, imaging systems involving sound waves, to guide medical staff as they gave the injections. "With ultrasound, we can visualize the nerve. We can also see the things we don't want to hit, like blood vessels. And then you can watch your anesthetic kind of pooling around the nerve," Moake said. That tells the medical team that the nerve block has hit the mark.
"Importantly, there were no complications directly attributed to the nerve block, and children receiving the nerve block did not have longer ED stays."
Going forward
Moake hopes the study hits the mark, too, by giving health care teams Further information to guide their decision making when it comes to managing pain in children. It's the largest study of its kind looking at ultrasound-guided fascia iliaca compartment nerve blocks in children performed in emergency departments that were geographically and clinically diverse. The researchers did not receive any funding for the work. They did gain satisfaction from knowing it could have larger implications.
"My bigger thought about this research is that we looked at specific injury with one block type. But it's just one of many that we have out there available for different things. It's hopefully, from my perspective, the starting point for a broader expansion of the use of nerve blocks," Moake said.
