Wednesday, January 30, 2008

GIGO and the CABG

Dontcha just love it when you take your car to the shop for one problem, and they call you back about 7 hours later to tell you that, well, there's maybe a few more? When I was younger, this phone call always involved some problem with the carburetor; now, it's always some electronic gizmo gone haywire.

Something like that happens not infrequently when folks go to the hospital for emergent or elective surgery. "Well, sir, your appendicitis is treated, but we found out that you have diabetes." "The surgery to take out your ruptured spleen went great. The thing is, you aspirated and now have pneumonia, which is going to set back your recovery a few weeks." "Looks like you have had yourself a little heart attack while you were stressed in here. Must have happened when your mother in law came to visit." And so on.

Most of the time, these types of occurrences are pretty easily explained -- wound infections, perioperative pneumonia or cardiac problems, previously undiagnosed diabetes or hypertension. But there is a group of patients that have problems that are harder to understand; these are folks that have GI complications following cardiac surgery. For a variety of reasons, patients undergoing cardiac surgery (with coronary artery bypass grafting being the most common) can develop a range of complications that are physically remote and seemingly unrelated to the heart operation. This isn't common, but according to a recently published study, may be more frequent than we have previously understood.

Gastrointestinal Complications after Coronary Artery Bypass Grafting: A National Study of Morbidiy and Mortality Predictors is more than just a mouthful, it's the title of a review published in December's JACS. From the abstract:

Background

Previous single-institution studies have documented a 0.6% to 2.4% incidence of gastrointestinal (GI) complications after coronary artery bypass grafting (CABG), with an associated 14% to 63% mortality rate. To better determine the incidence and impact of GI complications after CABG, national outcomes for CABG were examined from 1998 to 2002.

Study Design

The Nationwide Inpatient Sample was queried for all patients undergoing CABG (ICD9 procedure codes 36.10 to 36.16). Two cohorts were compared: CABGs with and without GI complications. Both demographic and outcomes variables were compared by either t-test or chi-square analysis. Logistic regression analyses indicated potential predictors of CABG inpatient mortality and GI complications after CABG.

Results

The incidence of GI complications among 2.7 million CABGs identified was 4.1%. Total hospital length of stay (19.3 versus 8.8 days) and inpatient mortality (12.0% versus 2.5%, both p < style="font-weight: bold;">Factors associated with increased risk of GI complications included: age greater than 65 years (odds ratio [OR], 2.1); hemodialysis (OR, 3.4); intraaortic balloon pump (OR, 1.6); concomitant valve procedure (OR, 1.5); and procedure urgency (OR, 1.22). Use of an internal mammary graft was protective (OR, 0.5), but GI complications increased inpatient mortality risk (OR, 2.6).

Conclusions

This national population-based study indicates that GI complications after CABG occur at a higher rate than previously described, leading to increased hospital length of stay and mortality.


Interesting.

"Oh, BS," you say. "DocSurg, you've lost it, if you ever actually had it. How can you say this stinking pile of statistics is interesting?" Well, for starters, given my chosen profession, I can pretty much be assured of being asked to see this very type of patient every once in a while --- and I can be pretty confident in telling patients and families that if they are seeing my smiling face at some point after a CABG, they need to plan on a more than double the normal postop hospital stay, as well as a not inconsiderable increase in the risk of death . And those numbers come with or without my charming bedside manner.

Looking a bit deeper into the paper, there is a laundry list of problems that were teased out of the 2.7 million patient database and labeled as GI complications:
  • Intraabdominal Abscess 28.1%
  • Ileus 23.9%
  • GI ulcer (perforated or bleeding) 16.9%
  • Diverticulitis and Diverticular bleeding 14.4%
  • Pancreatitis 5.5%
  • Liver failure/hepatitis 5.1%
  • Mesenteric ischemia 4.4%
  • Esophageal ulceration or perforation 4%
  • Bowel obstruction 3.2%
  • Biliary tract complication/gallbladder disease 2.9%
  • Clostridium difficile colitis 1.5%
  • Appendicitis 0.2%

What jumps out at me are a few numbers --- the rate of ileus (about 24%) is much higher than I would have anticipated. Part of the problem with labeling an ileus as a complication is that it is a diagnosis that increases the reimbursement a hospital receives from Medicare; in my experience, that leads to overdiagnosis by hospital coders (and I have indeed had this very problem at a local hospital; when I would write in the chart that the patient's expected postoperative ileus had not resolved --- in other words, after a major bowel operation, it is expected that it will take a few days for GI tract function to recover --- I was labeled as having an inordinately high complication rate, because the hospital coders listed ileus as a complication. Needless to say, that word has not been written by my hand in a patient's chart since). So, for argument's sake, let's just throw that out of the list.

Even with "ileus" on the trash heap, intraabdominal and hepatic abscesses remain the most frequent post-CABG complication in the study. Though I am not a cardiac surgeon, I cannot recall ever having been asked to see a post-CABG patient with a hepatic abscess. Once again, this makes me a bit suspicious of how this study got its results.

Of the remaining complications on the list, there is one statistical oddity --- namely, gallbladder problems are relatively infrequent compared to my own personal (and highly subjective) experience. Actually, I'd say the top three reasons I get asked to see a post-CABG patient are cholecystitis, mesenteric ischemia (or the possibility of the same), and bowel obstruction, with pancreatitis in the near vicinity.

The article goes on to nicely summarize the costs and mortality associated with these postop problems, and also describes the current thinking about why some of these complications arise. Without going down a long, winding road with many forks that have to be fully explored, suffice it to say that a lot of this can result from poor gut perfusion --- there's a problem with delivering enough little red boxcars with their important load to the tissues in the abdomen.

OK. Cool. Nice paper, summarizing a pile of data (even though my eyes started to bleed when I read that this came from a database of 2,732,158 patients). But, since I'm particularly curmudgeonly today, and because I don't like to commit things to memory that may not be useful, let me throw a few tomatoes at this paper.

First of all, this study encompassed the period from 1998 through 2002; I guess I would ask, where's the more recent data, at least through 2005? This stuff is, I hope, available on a computer, and database searches for diagnosis codes are pretty doggone easy. But in asking that question, we really get to the heart of my worries about this type of data review ---- we are extrapolating data from diagnosis coding, done by thousands of hospital employees, using a set of diagnosis codes that are so inadequate, incomplete and confusing that they resemble a train schedule from pre-war Italy. I am not criticizing the authors for their choice of data --- it's what is available --- but I am not convinced that we should draw sweeping conclusions from this type of data analysis.

"Well, DocSurg," you say, you are an arrogant @#^%&. Give us a better alternative!"

OK. Here it is.

You see, the above study relied on the National Inpatient Study, data collected by the Healthcare Cost and Utilization Project (HCUP), which is described as a "Federal-State-Industry partnership sponsored by the Agency for Healthcare Research and Quality." Once again, this data is pretty much generated by and collected by non-clinical personnel (I'm quite sure that there are clinicians involved along the way). The Society of Thoracic Surgeons database, however, has a far greater degree of physician input; the surgeon involved with the case fills out the form, which has places for patient risk data, complications, etc. The data is entered online, and there is even a really cool risk calculator that allows real-time feedback of what a patient's risk-adjusted expected morbidity and mortality rates should be.

So what? Is there a difference between what a surgeon considers risks and complications and what a hospital coder does? You bet our sweet patootie there is. As I alluded to above, hospital coding is all geared towards one thing --- getting paid. And, quite frankly, they are getting shafted when it comes to reimbursement for the sickest patients (not to mention outright fraud on the part of some insurers), and they need to fight like the Hansen brothers for every penny they can. Because of our convoluted payment system, they get paid more when an "ileus" is coded, for example. So, that leaves me a bit suspicious of the kind of studies generated from sifting through data from hospital diagnosis codes. Or, to put it another way, GIGO -- garbage in, garbage out.

Tuesday, January 22, 2008

A word on words


She says no when she means yes
And what she wants you know that I can't guess
When we want more you know we ask for less
Such is the language of love

The late Mr. Fogelberg said quite a bit about communicating with women in "The Language of Love," and most of it rings true. We do our best to get our point across with words that are often inadequate for the task at hand, and chaos (as well as hurt feelings) can result.

The same problem can plague doctor-patient communication. The words physicians use when talking with patients and their families can be frightening, misconstrued, or simply incomprehensible. Similarly, patients often struggle with an inability to describe their symptoms in a manner that allows a physician to adequately understand their complaints. As well, there is ample evidence that much of the discussion that occurs in the physician's office is heard, but not understood --- it sort of floats in one ear and out the other.

The problem for folks on my side of the stethoscope is that there frequently are no other words we can use when talking with patients. I mean, really, say some of these things out loud and tell me they don't come off as weird, impossible, or downright dangerous:

Vein stripping --- that's gotta hurt
Myocardial infarction --- are you describing passing gas in some sort of automobile?
Aggressive debridement of a wound --- oooh, the pictures in my mind are not pretty
Incision and drainage --- ouch
Pancreatitis --- OK, "itis" as in "tonsillitis," or as in "oh my god-itis?"
Aortic aneurysm --- that's a nice, soft phrase; it can't be that bad
Dyspareunia --- as painful to say as it is in real life
Perfusion --- isn't that when you put two "pers" together?
Gangrene --- I know that one from a WWII flick! But didn't the guy die in that movie?
Babinski's reflex --- is that what happens when you get sick watching the ice skating judges award perfect scores only to Russians?
Complications --- such a, well, complicated word
Perforation ---- I bet we're not talking about the little holes in a piece of paper, are we?
Myonecrosis --- sounds like a movie with Bela Lugosi
Rigid proctoscopy --- somehow, I suspect I'm not going to like this very much
Organ of Zuckerkandl --- oh, come on now, this one has to be a joke
Hematochezia --- Gesundheit!
Pneumothorax --- didn't Dr. Seuss write about these guys?
Cholangitis --- if it wasn't for the "itis" part, this sounds like a tropical drink
Achalasia --- is that part of Indonesia?
Lymphoscintigraphy --- scintillating maps featuring nymphomaniacs?
Mediastinitis --- there you go with that whole "itis" thing again
Toxic megacolon --- I'm not sure that I want to hear "toxic" and "colon" in the same sentence


What we've got here is a failure to communicate. This list can go on and on -- Dorland's Medical Dictionary is rather long. When docs talk to each other, we throw these words around casually, because they have real meaning to us and are not some abstract idea. The difficulty for us is to figure out a way to make these words have some real meaning for patients, to ensure that they understand the situation they may be in and what they may be faced with in terms of potential complications.

While that's our goal, I can say with all honesty that it doesn't always come across that way. And as every married man can verify, that's also what happens during those little "kitchen discussions" with our wives. So, the next time you are in a doctor's office, and you think you have heard something you either don't like or don't quite get, make sure you don't act like a wife (or husband -- don't want anyone to think I'm too sexist) --- speak up, ask for clarification, and don't get too upset if we're less than perfect in our communication skills.

Thursday, January 17, 2008

Double, "Bubble," Toil and Trouble

Double, double, toil and trouble; Fire burn, and cauldron bubble

I'll let you in on a little secret --- surgeons like to operate. I know that may not come as a great surprise, but when you stop and think about it ("Hmm, there are people out there who like to open other people up and fix what's inside"), it sounds a bit odd. And for some of you, what may be even more strange is that there are some operations that are generally kind of fun to do. One of those is a pancreatic cystgastrostomy.

Time out --- what the H E double hockey sticks is a pancreatic cystgastrostomy? Simply put, it's draining a fluid collection into the GI tract.

Okey dokey, now that's clear, why would there actually be fluid around the pancreas? The short answer is pancreatitis. The long answer is pancreatitis severe enough to cause a fair amount of tissue damage. As this resolves, a fluid collection in the surrounding area can form into a pseudocyst --- "pseudo" in the sense that because it is not a true cyst with a cyst lining, the walls of the cyst are formed by the inflammation and scarring in the surrounding tissues that result from pancreatitis. Because the pancreas lies behind the stomach, patients will have symptoms of extreme fullness when they try to eat. These things can become fairly large, tracking down the retroperitoneum, and occasionally get infected or can even be associated with significant hemorrhage. When large enough, they need to be drained --- and an elegant, simple method of draining them is into the GI tract, usually into the stomach with a cystgastrostomy.

This is a very satisfying operation, usually not very complicated, and usually not very time consuming --- and it can be described as a "double bubble," with one cavity being opened into another one. The front wall of the stomach is opened, exposing the posterior wall and the accompanying bulge of the pseudocyst behind it. It's not rocket science from here ---- the posterior stomach wall and wall of the cyst are opened, allowing the fluid to drain directly into the stomach and downstream. The only key to the operation is making sure that the two walls are sutured together to prevent bleeding.

I do not tend to see a large number of patients needing this procedure --- in fact, probably only a handful in the past dozen years --- so I have not had the opportunity to do this surgery with a minimally invasive approach. Basically, there is nothing about this procedure that precludes a laparoscopic approach, which minimizes discomfort and decreases recovery time.

So, getting back to our not so obscure literary reference, the three witches in Shakespeare's Macbeth (Act 4, Scene 1) chant the lines
Double, double, toil and trouble;
Fire burn, and cauldron bubble
as Macbeth approaches. In response to his questions, they conjure up three spirits with three warnings and prophecies, which tell him to "beware Macduff," that "none of woman born shall harm Macbeth," and that he will "never vanquish'd be until Great Birnam Wood to High Dunsinane Hill shall come against him." Assuming his safety based upon these prophecies, Macbeth has everyone in Macduff's castle put to death.

Ooops. Things didn't quite turn out for the young prince of Denmark.

Well, we can say that the three witches here are gallstones, alcohol, and more alcohol --- the three biggest causes of pancreatitis, which causes the "fire to burn" in the abdomen, and sometimes generates a pseudocyst -- the "cauldron bubble," so to speak, producing a "double bubble." The three prophecies that ensue would then be:
  • beware the damage that has been done --- pancreatitis can be a destructive force in the abdomen that rages for quite a while. Or, to quote Lady Macbeth, "What's done is done."
  • none of woman born can make it go away --- unless that child carries a sharp knife
  • the disease once vanquished can come against you once again --- for the patient afflicted with alcohol-induced pancreatitis, it's time to empty the tequila bottles or get ready to see the inside of the operating room again.......sort of like the mistake that Macbeth made
If the result of the "witches' brew" of acute pancreatitis is only a pseudocyst, instead of an all out destructive assault on the abdomen requiring pancreatic necrosectomy, the patient and surgeon should be very, very thankful. And not just because it's a fun operation.

Tuesday, January 15, 2008

To PE, or Not to PE

Pulmonary embolism.

There. I said it. Just like saying "Lord Voldemort." As "they say," naming your fear is a first step in dealing with it, and we surgeons certainly fear the possibility of a patient experiencing a PE. It is really not a terribly frequent complication of surgical care, but it can be devastating, and even fatal. What is it, and what do we do about it? To answer that question, we first must take a look at how your body makes clot --- it is a complicated cascade of events:

OK. That looks a bit too complicated, especially for a simple-minded surgeon. Maybe we should try another approach. Let's just say that when you cut yourself shaving, and the bleeding stops, it's a result of a rapid interaction of a whole range of clotting factors, tissue mediators, and enzymes. Sort of like having a tornado assemble a VW Bug in your front yard --- right this second!

"But DocSurg," you say. "Don't you worry more about bleeding than clotting?" Er, yes, to a point. Bleeding, in the absence of a genetic abnormality or a dastardly pharmaceutical insult, is generally a surgical issue. In other words, we can get a handle on it the vast majority of the time, thanks to sutures, cautery, and the wonderful action of the clotting cascade (some other time we'll get into the issues of audible bleeding and DIC).

Most folks tend to think about clotting abnormalities and difficulties with surgery in terms of hemophilia, because it is a well-known disease process with well-established treatment. What most do not know, however, is that some patients do not fail to make clot, but rather do so all too well, and often do so well away from the operative field ---most importantly, this problem (venous thrombosis and thromboembolism, or VTE) is more common than hemophilia. And wouldn't you know it, surgery is a significant risk factor for VTE.

I certainly do not want to oversimplify this very complicated issue, but I would like to make a few salient points about VTE associated with surgery in general, and general surgery in particular. Basically, there are two broad groups that are at an increased risk for deep vein thrombosis (DVT) and pulmonary embolism (PE) with surgery:

  • Those with a genetic predisposition to VTE, associated with an abnormality of one of the factors in the clotting cascade --- an example would be a patient with a Factor V Leiden deficiency. These patients are at a significantly increased risk for VTE with trauma, surgery, prolonged inactivity, etc......but may not know they have a problem when they present for surgery. A family history may be unknown or negative. These folks can often surprise surgeons by presenting early after surgery with a DVT or PE, even after undergoing a relatively minor procedure. They may require lifelong anticoagulation.
  • Those patients without a genetic predisposition to VTE --- i.e., everybody else, many of whom have any of a number of other risk factors (smoking, oral contraceptive use, obesity, ....and the list goes on). It is a pretty accurate statement that every hospitalized patient has at least one predisposing factor for venous thrombosis.
What's the difference between the two groups? From a practical standpoint, "forewarned is forearmed," and the knowledge that a patient has a hyperthrombotic state allows a surgeon to aggressively treat them with perioperative prophylactic anticoagulation (how aggressive is debatable, and dependent upon the type of surgery involved). However, every patient undergoing a significant abdominal operation deserves some sort of VTE prophylaxis --- and once again, there are a number of risk factors that dictate the degree of aggressiveness in one's approach (there is a great resource at DVT.ORG that explains the rationale for prophylaxis in great detail).

Why is the idea of VTE prophylaxis important? Because pulmonary embolism is potentially fatal, frequently preventable, and associated with significant morbidity (and cost) in those it does not kill. While the surgical literature is replete with studies documenting this, a reasonabe one was published in last month's American Journal of Surgery --- Postoperative Pulmonary Embolism: Timing, Diagnosis, Treatment, and Outcomes.
Our study included 115 patients. Prophylaxis was administered preoperatively in 31% of patients and postoperatively in 56% of patients. The diagnosis was obtained by computed tomography scan in 74 patients (64%), ventilation-perfusion scan in 24 patients (21%), angiogram in 8 patients (7%), and other modalities in 9 patients (8%). The time elapsed between surgery and the diagnosis of PE varied significantly by patient age (<40>P = .02). The majority of patients with PE were treated with anticoagulation (83%). Morbidity and mortality rates both were 9%.
OK, I lied. This isn't a particularly good study, but it is enlightening for a few things. First of all, they had a documented rate of preoperative prophylaxis of only 31% in these patients --- and while they speculated this could have been an error in documentation, that's a pretty big red flag for any attorney scouring the patient's record. Secondly, the overall incidence of postoperative PE at their institution was extremely low at 0.09%, and remained stable throughout the study period (1999-2004). What is not listed is the overall incidence of postoperative DVT, which is the precursor to PE and may be associated with subclinical episodes of PE.

Additionally, the authors main reason for putting this article out at all is the discrepancy seen in the time following surgery that patients presented with their PE --- younger patients presented earlier than older patients. Although no mention was made of a workup in these patients for a hyperthrombotic process, I wonder whether the younger patients had a higher incidence of this than the older ones. Older patients tend to be less mobile after discharge from the hospital, may have undergone more extensive surgery, and tend to stay a bit less well hydrated after discharge (in my own experience) ---- all things that increase their risk for VTE.

Even though the overall rate of postoperative PE is low, and the mortality rate is low when it occurs, this is felt to be in many cases a preventable problem. And though I am really, really, really suspicious when the government says they insist on everyone complying with a set of guidelines to improve patient care, this time I think they are right --- along with a variety of other alphabet soup organizations, CMS will be looking at DVT prophylaxis as a quality indicator for its rather odious pay-for-performance scheme.

In the end, what should patients who are to undergo surgery do? Never fear, DocSurg is here with a few helpful hints:
  • If you or an immediate family member has had a DVT ---TELL YOUR SURGEON!
  • If you are having major abdominal surgery, ask about VTE prophylaxis --- this may include sequential compression devices or injections of Heparin or a low molecular weight Heparin
  • Get out of bed --- frequently --- and walk. Being mobile decreases your risk for DVT substantially.
  • When you get home, don't just stay there --- get out and walk. Go to the mall. Go to Starbucks. Walk in the park. Just don't park your behind on the sofa.
  • Stay hydrated --- significant dehydration increases the risk for DVT. The best way I can explain this is by comparing your venous system to the oil in your car engine --- increasing viscosity is bad, and the less fluid you have in your system, the more viscous your blood becomes.

So, really, we're partners in this --- we need you to help us keep you from getting a significant postoperative problem.

Thanks in advance!

Wednesday, January 09, 2008

How I spent my Christmas vacation

The few weeks leading up to and just following the Christmas holidays are always the busiest times for general surgeons. Hence, the complete lack of attention to my real job, blogging. Why would this time be busier than others? At the end of the calendar year, patients come out of the woodwork with nagging problems that need attention, but which seem more important as they have met the all important deductible for the year. So, we do a fair number of hernia repairs, cholecystectomies, and the like in December. Unfortunately, human nature being what it is, we tend to see more patients with neglected problems that show up in the ED or in our offices, prompted by concerned family members, who need something done very soon (actually, they needed it some time ago, but now it's a real crisis). And since we also like to have time off at this time of the year, there are fewer of us to go around when we have an increase in patient load.

But by far, the biggest source of increased workload in late December comes from the ED, as patients show up there in droves for the same reason they appear in my office. This year, I was overwhelmed with a bonanza of "gifts" from the ED, so with apologies to the Mackenzie brothers, this version of The Twelve Days of Christmas will give you a little insight into how I spent my Christmas "vacation:"

On the first day of Christmas, my ED gave to me
A case of stinky butt pus

On the second day of Christmas, my ED gave to me
Two drunksicles
And a case of stinky butt pus!

On the third day of Christmas, my ED gave to me
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the fourth day of Christmas, my ED gave to me
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the fifth day of Christmas, my ED gave to me
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the sixth day of Christmas, my ED gave to me
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the seventh day of Christmas, my ED gave to me
Seven stab wounds a-wailing
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the eighth day of Christmas, my ED gave to me
Eight viscera perforating
Seven stab wounds a-wailing
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the ninth day of Christmas, my ED gave to me
Nine ladies with PID
Eight viscera perforating
Seven stab wounds a-wailing
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the tenth day of Christmas, my ED gave to me
Ten ruptured spleens
Nine ladies with PID
Eight viscera perforating
Seven stab wounds a-wailing
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the eleventh day of Christmas, my ED gave to me
Eleven loaded DUIs crashing
Ten ruptured spleens
Nine ladies with PID
Eight viscera perforating
Seven stab wounds a-wailing
Six appy's a-rupturing
Five golden gallstones!
Four rectal foreign bodies
Three GI bleeders
Two drunksicles
And a case of stinky butt pus!

On the twelfth day of Christmas, my ED gave to me
Nothing -- because I was finally off call!

On the thirteenth day of Christmas, SWIMBO gave to me, an extremely dry martini!