Sedating patients before a nerve block needed to diagnose or treat chronic pain increases the costs, risks and potential for unnecessary surgeries, and sedation does not increase patient satisfaction or long-term pain control, according to new research.
Sedation doesnt help, but it does add expense and risk, study leader Steven P. Cohen, MD, said in a news release. Cohen is a professor of anesthesiology and critical care medicine at Johns Hopkins University School of Medicine in Baltimore. In some places, every patient is being sedated. Our research shows it should be used very sparingly.
Nerve blocks, performed by injecting anesthetics and or steroids into any number of areas of the body, from the spinal column to the hip joint, often are performed ahead of surgery and in addition to other invasive procedures, such as the ablation of nerves to treat arthritis in the back, to more accurately pin down the source of pain. Increasingly, physicians have used light or even deep sedation as a way to ease patient anxiety and pain when the injection is given.
However, results of the new study, reported Feb. 13 on the website of the journal Pain Medicine, show sedation before a nerve block significantly increases false-positive results, meaning patients are more likely to undergo surgeries and other procedures that wont cure the underlying pain. Sedation also carries its own health risks.
For the study, Cohen and researchers from several other medical centers in the U.S. recruited 73 patients with back or limb pain who were scheduled to receive multiple nerve blocks. About half of the group received the first injection with sedation and the second without sedation. The remaining patients received their injections in the opposite order.
Patients were given six-hour pain diaries, a routine step to help patients determine whether the injections bring relief, and were asked to rate their satisfaction with the treatment. A month later, the patients were seen again and asked to rate their pain and function after the treatment.
The sedated patients reported less pain immediately after the nerve block injection, but on every other measure from 30-day pain assessments to overall patient satisfaction the results were the same whether or not they were sedated.
A lot of cost for very little benefit, Cohen said in the release.
The increase in false-positive results can result from many factors, according to Cohen, such as the sedative medication itself relieving pain or relaxing muscles. Patients also may need to take extra time away from daily activities after being under anesthesia, while more rest alone could relieve pain.
If patients think the nerve block eased the underlying pain, physicians often move ahead with appropriate treatment, Cohen added, but false-positives mean many patients could end up still in pain, even after undergoing a potentially unnecessary procedure.
Cohen said many physicians may use sedation in a sincere effort to make the procedure less traumatic for patients, but there also is a financial incentive.
Unfortunately, medicine in many places has become a business. The fact is, you get paid more money to do the procedure with sedation, he said in the release. The costs of anesthesia can be more than the fee for the procedure itself. And patients are getting harmed.
The research was funded by the Center for Rehabilitation Sciences Research, part of the Uniformed Services University of the Health Sciences in Bethesda, Md.
Study abstract: http://onlinelibrary.wiley.com/doi/10.1111/pme.12389/abstract