Tuesday, January 17, 2017

More about adhesions and postoperative pain

In November 2016, I wrote about adhesions and whether they are the cause of chronic abdominal pain. I and several surgeons who commented felt they weren't.

Some new information from the February 2017 issue of the journal Surgery is just in. A randomized, double blind, placebo-controlled trial from The Netherlands was originally published in 2003 after one year of follow-up. At that time, there was no apparent benefit from an operation to lyse [divide] all adhesions laparoscopically in 52 patients compared to a placebo operation that involved performing only laparoscopy to assess the extent of adhesions in 48.

The current paper looked at outcomes 12 years after the original surgery was done. Follow-up was available for 73% of the patients—42 in the group who had adhesiolysis and 31 who had laparoscopy only.

The authors concluded, “Laparoscopic adhesiolysis was less beneficial than laparoscopy alone in the long term. Secondly, there appeared to be a powerful, long-lasting placebo effect of laparoscopy. Because adhesiolysis is associated with an increased risk of operative complications, avoiding this treatment may result in less morbidity and health care costs.”

Unfortunately the paper has a few flaws.

No cost data were included.

One year after the original surgery, they told the subjects which groups they were in, and those who had only laparoscopy were given the option to undergo adhesiolysis if they wanted to. The math regarding patients in both groups is confusing. Here is the flow diagram for the study:

Click on figure to enlarge it
At 12 months, the numbers should be 51 for the laparoscopic adhesiolysis group and 47 for the laparoscopy alone group.

In the first paragraph of the results section, it says 12 of the 31 placebo patients underwent adhesiolysis. But the flow chart says "17 placebo patients applied to the offerend adhesiolysis." I do not know what "offerend" means or whether it is simply a typo for “offered.”

The authors said that at the first year of follow-up, quality of life outcomes were no different between the two groups but they did not explain why 12 of the original 48 laparoscopy only patients decided to undergo lysis of adhesions after they were told they were in the placebo group. Requesting another operation implies dissatisfaction with the first procedure.

More math confusion accompanies Table III which is difficult to interpret especially regarding the numbers for the placebo group. The table below indicates that only one patient in the placebo group had a reoperation. But the figure reproduced above shows two patients had lysis of adhesions in the first year after the original surgery. And what about the 12 patients who underwent lysis of adhesions (a reoperation) after they were told they were in the placebo group? If those 12 plus the 2 who had reoperations during the first year of the study were counted as reoperations, there would be no difference in reops between the two groups.
Click on table to enlarge it
In the discussion, they said "placebo patients who did not cross over to adhesiolysis did much better overall" but showed no data to support that statement.

Much as I’d like to agree with this paper, I can’t.

It doesn’t convince me that lysis of adhesions is worse that a placebo operation, but at least no one in the placebo group required euthanasia because of pain.

An email to the corresponding author of the paper was not answered.


artiger said...

All that the study tells me is that we are going to continue the arguments (for and against) for a long time to come. In the meantime, I stick with my original position.

Skeptical Scalpel said...

I had hoped the paper I just wrote about would help settle the issue but it doesn't. It's another one that requires reading more than just the abstract.

GI Doc K said...

As a gastroenterologist, we see our fair share of patients with abdominal pain with no clear etiology (often after the "million dollar" evaluation). A common scenario is that a patient has for example RUQ pain, then gets a cholecystectomy for biliary dyskinesia or stones (surgeon tells them there was "lots of scar tissue" or at least that's what they tell me), pain resolves for maybe 1-2 weeks, then recurs worse than prior and continues for months to years. The patient then comes to see me for a second or third or fourth opinion after multiple negative tests including imaging. Often, they are already on a PPI in case this is GERD, laxatives for constipation and sometimes narcotics, neurontin, etc, etc. The answer may be irritable bowel syndrome or simply chronic abdominal pain NOS, but the patient wants an answer. I usually tell them that even though they have scar, it's unclear that this is the cause of their pain and they are unlikely to find a surgeon who will operate.

Skeptical Scalpel said...

GI Doc K, that's a familiar story. Everyone who has gallstones is not necessarily symptomatic from them. The art of history taking is disappearing. When you see these patients later, you often find their original symptoms were not consistent with biliary colic or cholecystitis. Biliary dyskinesia is an enigma. I have never been convinced it's a real disease.

As discussed at length in my previous post about adhesions, I think most surgeons don't believe in operating on them to relieve pain. But some do. If a patient sees enough surgeons, one will eventually perform the surgery.

Cate said...

I wish someone could figure out what causes chronic abdominal pain. After 2 c-sections, cholecystectomy, and a hysterectomy (4 separate surgeries), I have been in pain for the past 8 years. I was fine before the surgeries. All were reasonably uneventful, but with the report of "lots of scar tissue". This is literally cramping my style. I am unable to do much of anything anymore. It's better than being dead, but isn't the life I used to have.

Skeptical Scalpel said...

Cate, I'm sorry to hear about your pain. I wish I had some encouraging suggestions for you.

goldy said...

I had an exploratory lap in 1980 and again in 1984. I was DES exposed and had a lot of female problems including cancer cells on my cervix every time I had a pap. That scar has caused me a lot of problems but I refuse to have any surgery on it. I have been told I have lot of scar tissue and things are stuck together. Yeah they feel like they are! It pulls everything in the scar and around it inward. However I'm sticking to my guns and not having anything done. No thanks!

Skeptical Scalpel said...

Goldy, thanks for commenting. I hope the problem gets better. Meanwhile hang in there.

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