Friday, April 29, 2011

DNR Patients and Outcomes of Surgery: Two Papers, Same Data, Different Results

Just the other day, a paper from Archives of Surgery reported that patients who have existing DNR orders have a higher postoperative mortality rate than patients who do not. This, of course was not surprising since people with DNR status are usually old and sick. The paper did receive some media attention with routine “churnalistic”* coverage. [HealthDay News, Medscape, MSN Health]

Having read the paper with mild interest, I didn’t think too much about it until yesterday when the May issue of the journal Critical Care Medicine [CCM] arrived. In it was a paper which is very similar to the Archives article. Let’s compare the two papers. The Archives paper was entitled “High mortality in surgical patients with do-not-resuscitate orders: analysis of 8256 patients,” and the CCM paper “Pre-existing do-not-resuscitate orders are not associated with increased postoperative morbidity at 30 days in surgical patients.”

Both papers used data from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) Database for the years 200-2008. The Archives paper found some 4128 DNR patients while the CCM paper found only 2199. Both studies matched the DNR patients with non-DNR patients who had similar operations and demographics.

Both papers found that DNR patients were a little more than twice as likely to die within 30 days than non-DNR patients, but the mortality rates were markedly different. The Archives mortality rates were 23.1% for the DNR and 8.4% for the non-DNR versus the CCM cohorts which were 12.5% and 5.2% respectively.

The Archives paper noted a significantly higher rate of major complications for the DNR patients with no difference in minor complications whereas the CCM paper reported that the DNR patients actually had significantly fewer wound infections and no difference in the major complication rate.

I could go on but I think you get the idea. Both sets of authors did mention that their studies could be confounded by the limitations of retrospective studies and the use of an administrative database, such as the NSQIP.

What is not clear and certainly beyond my ability to explain, are the marked discrepancies in the number of patients found with DNR orders when the time period of both studies was identical and the substantial differences in mortality and complication rates.

Bottom line. Although they are at a higher risk of death, DNR patients may undergo necessary surgical procedures with a reasonable expectation of success.

*Churnalism is a news article that is published as journalism, but is essentially a press release without much added

Thursday, April 28, 2011

Forgettable Stadium Names

Yesterday the Oakland-Alameda County Coliseum was renamed the Coliseum. It might be possible to think of a worse name for a sports venue, but right now I can’t. However, it is in keeping with the recent trend of selling naming rights to the highest bidder. Some 20 of the current 31 NFL stadiums are named for corporations including the melodious and memorable Mall of America Field at Hubert H. Humphrey Metrodome, Lucas Oil Stadium, Lincoln Financial Field, LP Field, Qualcomm Field, Qwest Field, Sun Life Stadium [formerly LandShark Stadium], M & T Bank Stadium and Invesco Field at Mile High. Even some of the non-corporate names [Cowboys Stadium, Cleveland Browns Stadium and the Georgia Dome] are quite pedestrian.

It gets a little crazy at times as noted in this excerpt about the stadium in St. Louis from Wikipedia: “As part of a deal to sell the naming rights to Rams Park (now the Russell Athletic Training Center), the Rams' training facility in Earth City, Missouri, to sportswear manufacturer Russell Athletic, the Rams agreed to rename the Edward Jones Dome to Russell Athletic Field for the Rams' Monday Night Football game against the Chicago Bears on December 11, 2006. The renaming was for the one night only.”

And just look at the fate of some of the companies who at one time had stadiums named after them. The following went into bankruptcy, were acquired by another corporation or otherwise had to relinquish their naming rights: Pro Player, CMGi, PSINet, Alltel, McAfee, Network Associates, 3Com, Ericsson, and Trans World Airlines.

Contrast the above with the 20-team English Premier League, whose football [soccer] stadium names evoke historic, even regal images. Here are a few: Stamford Bridge, Craven Cottage, White Hart Lane, Old Trafford, St. James’s Park, Brittania Stadium, The Hawthorns, Molineux Stadium and my favorite, The Stadium of Light. Only three EPL stadiums are named after corporations.

I'm sure those living in Northern California can't wait to experience the nostalgia and atmosphere at the Coliseum. As for me, I'll take The Stadium of Light.

Tuesday, April 26, 2011

Clever New Diagnostic Test for Pancreatitis Fails to Measure Up

Today Eurekalert!, a science news service, featured a story about a new diagnostic test that at first glance seems interesting and possibly of value. Researchers at the University of Texas have developed a simple, inexpensive test for diagnosing acute pancreatitis using an LED sensor, aluminum foil, gelatin, milk and lye. Using about $1.00 worth of materials, the test identifies the presence of high levels of a pancreatic enzyme, trypsin, in the blood and takes only a few minutes to do.

According to the press release on the Texas Science website, “The sensor could help prevent damage from acute pancreatitis, which is a sudden inflammation of the pancreas that can lead to severe stomach pain, nausea, fever, shock and in some cases, death.”

Unfortunately, the breakthrough is not really all that dramatic.

Acute pancreatitis usually resolves in a few days. It is treated conservatively using bowel rest, intravenous fluids to maintain hydration and pain medication.

Pancreatitis is commonly diagnosed by history and physical examination and confirmed by elevated levels of one or two blood tests, serum amylase and lipase. Lipase, which rises more slowly but remains elevated in the blood longer than amylase, is the preferred test. Checking on line reveals that a serum lipase test can be obtained for as little as $39.00 retail. The actual cost of performing the test is under $6.00. In a hospital emergency department, the result is available within an hour of obtaining a blood sample, which negates the small speed advantage of the gelatin-based test. And let’s not forget that according to Joint Commission and other regulatory organizations, any point-of-care test must undergo frequent calibration to assure consistent quality. Technically, even a simple test for occult fecal blood cannot be performed at the bedside in the 21st century.

It is not clear exactly how a diagnostic test that might save a few dollars and produces a result a little quicker than a standard blood test can prevent damage to the pancreas. Since the test is qualitative [elevated trypsin levels are present or not] rather than quantitative like the lipase test [a numerical value is reported], the gelatin test cannot be used to determine whether the level of pancreatic inflammation is increasing or not.

In fairness, the press release does point out that the gelatin test could be used in developing countries where automated blood analyzers might not exist or in situations where electrical power has failed. This of course is based on the assumption that aluminum foil, LED sensors gelatin etc are handy.

Bottom line. The test is ingenious but seems unlikely to replace standard blood tests for pancreatitis. Don’t believe everything you read in a press release.

[Note: Only 32 (7%) of the 451 words in this post were taken directly from the press release.] 

Monday, April 25, 2011

Alarms! Sounding the Alarm on Alarms, Finally

“Patient alarms often unheard, unheeded” states a recent headline in the Boston Globe. Now the Joint Commission and the FDA are going to target “alarm fatigue” as a patient safety priority. Apparently it is not a very high priority as the article describing the effort states that the two organizations will be meeting “over the next few months” to “pinpoint a strategy.”

My question is, where has everyone been? This issue has been apparent for years to anyone who has ever worked in an intensive care unit. Walk into any ICU and within 30 seconds, you will hear an alarm sound its annoying bleat and see the staff going about their business without a second thought.

As far back as the early 1990s, studies documented the issues. There are too many alarms. In 1994, researchers from Ohio published a study in which they played some 33 different common alarm tones for 100 ICU staff members. Only 50% of them were able to identify the source of each alarm. The authors concluded that there were too many alarms for even experienced staff to identify and proposed that alarms should be used for only critical problems.

Another 1994 study from a pediatric ICU observed alarm activity over a week’s time. They noted that of 2,176 alarm soundings, 68% were false, 26.5% were induced by staff dealing with patients and only 5.5% were actually significant.

An interesting study performed on college students in 1995 showed that people respond to alarms on the basis of their expectations. In other words, if an alarm is known to usually be false, the individual is less likely to respond to it. Obviously, if 95% of alarms in an ICU are false, the staff will be conditioned to ignore them.

There have been many other papers on the subject documenting the above as well as the stress on the staff that the constant level of noise produces.

In 2011, the problem is even worse as more and more devices have related alarms. For example, the push to prevent patient falls has prompted the invention of the bed alarm. Some of these alarms are so sensitive that the mere touching of the bed by staff triggers the alarm.

The solution to the problem of alarm fatigue is not simple. Every new device seems to come with its own random noise and sound level. A concerted effort by device manufacturers, regulatory agencies and hospitals is needed. My suggestion is to 1) scrap all current alarms and develop standardized tones for a select few important events and 2) improve the sensitivity of triggers to reduce the false alarm rate. Good luck.

Wednesday, April 20, 2011

Surgeon performance degraded by drinking to excess the night before. What excuses do reporters have?

A big media splash accompanied the publication of a paper in the April 2011 issue of the Archives of Surgery about surgeon performance on a simulator after a night of alcohol ingestion. Briefly, the paper showed that drinking to excess can negatively affect performance of tasks involving simulated laparoscopic cholecystectomy the next day even if alcohol levels are zero. What is not clear is whether making small errors on a simulator means that patients would be a) similarly vulnerable in a real operation and b) harmed by these errors. There is a big difference between playing with a simulator in a laboratory and operating on a living, breathing patient.

What is clear is that the reporting of this story leaves a lot to be desired. I looked at a number of articles and found numerous mistakes leading me to wonder if alcohol consumption affects reporters negatively too.

“Hung-over surgeons more error-prone” was how Reuters chose to headline the story. As the authors of the paper point out “There is no consensus definition of hangover and most studies identify various constellations of symptoms, including headache, diarrhea, anorexia, fatigue, and nausea.” There was no mention in the paper that subjects of the research had any of these symptoms.

“Time to give surgeons breathalizers [sic]?” was the headline on CNET News. The only problem is that the study was about the effects of alcohol on performance the day after drinking. Only one subject even had a detectable level of alcohol on a breath test the next day. And “breathalyzers” is misspelled. This story did point out the error in the Reuters headline regarding the absence of true hangovers. wrote “A second dinner-and-drinks experiment -- this one involving a group of surgery trainees and a control group that did not drink…” A similar error was made by which said, “In a two-part study involving 16 medical students and eight experienced surgeons…” The subjects in this group were students at Queens University, Belfast, not surgery trainees or medical students.
A website called AccessRx wrote “A recent study has shown that surgeons are more likely to make mistakes during a surgery if they are hung-over, even if there is no detectable alcohol in their system.” And they also say that the non-surgeon subjects were medical students. Many articles on this subject feature dramatic photos of seemingly distressed doctors in surgical garb. The one at AccessRx was at least amusing [below].

[He forgot his mask. Is that glass sterile?]

This is my favorite. From [printed in its entirety]:

“(FOX 25 / - This might not come as a surprise, but a new study says that surgeons who drink a lot the night before surgery are more likely to make mistakes the next day. Irish researchers set up two simulated surgeries. In the first, 16 college students were told to either drink or not drink the evening before. In the second, eight experts drank all they wanted. The study showed that there were more errors among the drinkers.”

The folks at AccessRx called for action stating emphatically, “Should some sort of regulation be put in place to restrict surgeons from drinking the night before a surgery?” 

Similarly, I call for alcohol testing of reporters before they file their stories.

Monday, April 18, 2011

Sexism and Surgery: A Surgical Leader Falters

A well-known academic surgeon was “hoist with his own petard” via an unusual commentary he wrote in his capacity as editor of Surgery News, the official newspaper of the American College of Surgeons (ACS). Lazar Greenfield, Emeritus Professor of Surgery at the University of Michigan and inventor of the Greenfield filter, a device used for prevention of pulmonary embolus (clots traveling to the lungs), was forced to resign his position as editor and also as president-elect of the ACS.

The entire issue of the newspaper containing the piece was retracted by the ACS but it can be read here. The editorial, an apparent attempt at Valentine’s Day humor, suggested that women experienced lighter moods after unprotected sex with men and extolled the virtues of semen as a substitute for chocolate as a Valentine’s Day gift.

Rather predictably, the editorial was not viewed favorably by a number of women. Personally, I thought it was inappropriate for an official publication of the largest surgical organization in the country, and worse, it wasn’t funny. In fact, I tweeted the following several weeks before the feces hit the fan and the story was finally noticed by the New York Times.

There have been a slew of comments ranging from Greenfield is the worst sexist since Andrew Dice Clay to women are too sensitive. So now a famous surgeon, known to have encouraged and mentored women entering surgery, is disgraced. And the ACS loses both ways because it took the leaders of the society way too long to resolve the problem and they lost a formerly respected leader anyway.

Bottom line. It’s 2011, and this sort of thing just doesn’t fly any more. I feel sorry for Dr. Greenfield, whom I’ve never met. He seems like a nice guy who made a mistake which proved fatal to an otherwise illustrious career. Too bad.

Obesity: New Products and Old Problems

You might be interested in the response of equipment manufacturers to the increase in the size of obese patients. Below you can see a photo of a wide-body wheelchair and a super wide-body bedside commode.

You will note that the bedside commode has a normal sized bucket but the seat is extra wide to accommodate the girth of morbidly obese patients.

Something probably not appreciated by most people is that a morbidly obese person’s body actually contains a normal sized individual surround by a large layer of adipose tissue.

Below is an abdominal CT scan which illustrates the point.

You can see that the organs are encased in body fat which extends to the limits (and beyond) of the CT scan table. The picture is grainy because the x-rays are partially absorbed by the thick fatty layer. This makes the interpretation of the images much more difficult.  So not only is the diagnosis of abdominal problems hindered by the fat, you can imagine how hard surgery must be. Or maybe you can’t. Take my word for it, it’s hard.

Recovery is also an issue due to impaired wound healing, increased incidence of infections, problems moving the patient, difficult intravenous access and many more.

Remember this when you order that second Big Mac with supersized fries.

Friday, April 15, 2011

Needle-Free Test for Premature Babies Means Less Pain. Not So.

Things are not always what they seem. Here’s a lesson for those who follow the medical literature. Read the paper, not the press release.
A press release touting the results of a drug monitoring study in premature babies from researchers in Northern Ireland states that the use of heel prick instead of venipuncture is less painful. Two major distributors of press releases, Science Daily and IANS published stories on this with the respective headlines “Needle-Free Test for Premature Babies” and “A painless, needle-free test for premature babies soon.”

Both reports quoted the principal author [obviously, directly from the press release] as follows, “This type of testing will obviously reduce the discomfort of medicine testing in these vulnerable patients.”

However, the objective of the paper as stated by the authors was to “…characterize the population pharmacokinetics…”of the antibiotic, metronidazole, which had apparently not been well-studied in neonates. There was no comparison of heel prick to venipuncture. All samples were drawn via heel prick. Furthermore, nowhere in the paper is there any mention of pain assessment in the babies.

The subject of pain associated with blood testing of babies has been extensively researched. A  1999 review (updated in 2007) by the respected Cochrane Collaboration found that venipuncture was in fact less painful that heel prick for obtaining blood from infants.

Bottom line. The study was about monitoring a drug, not pain. The assertion that heel prick is less painful than venipuncture for babies cannot be a valid conclusion based on the study as published. Press releases can be deceiving.

The lead author of the study did not respond to an email request for comment.