Monday, February 27, 2012
The pilgrimage to Arizona and Florida has begun as pitchers and catchers have reported and spring training is under way. Perhaps more than in any other sport, decision making in baseball mirrors the medical thought process. Baseball revels in the notion that past performance can predict the future and statistics seem to matter. Beyond batting average, runs batted in and earned run average, every situation seems to have been documented so that one can look back and see how well a right handed hitter swung the bat against a left handed pitcher with men in scoring position. From ordering tests that may not be necessary to injecting drugs that could be a lifesaver, medical care has come a long way from being based on intuition and anecdote.
Twenty five years ago, a CT scanner was a rare and expensive machine. The decision to order a head scan to look for bleeding in the brain was a big deal. But the technology spread quickly to almost every hospital and many walk in clinics and doctors’ offices. More scans were ordered and perhaps patients were getting tests and extra radiation that they didn’t need. With too many normal tests being down for relatively minor head bumps (remembering that the scan was supposed to look for bleeding), researchers using statistical analysis were able to develop rules and guidelines that doctors could rely upon to reassure a patient that nothing bad was going on when they hit their head.
The CT rules are pretty common sense. A patient needed a CT scan of the head if they were not completely awake within 2 hours after injury, there was evidence of a depressed skull fracture or basilar skull fracture, there were two or more episodes of vomiting, there was greater than 30 minutes of amnesia, there was a dangerous mechanism like getting hit by a care or falling down many stairs and if they were older than 65.
However, the guidelines needed some interpretation. While a CT scan wasn’t necessary, there was still the possibility that a tiny amount of bleeding could be present in the brain but it would have no consequences and wouldn’t need any intervention or operation…that is, unless the patient was on a blood thinner like Coumadin, Pradaxa or heparin. Then, there were no rules. Not needing a CT scan also meant that the patient didn’t need to be wakened routinely through the night. It also did not mean that complications of concussion (for example, headache, and difficulty concentrating and sleeping) were not a possibility.
Bleeding in the brain is always a big deal and it is a major complication of using TPA, the clot buster drug to try to treat and reverse stroke symptoms. There are rules and statistics for TPA use as well. If used in the appropriate patient, the success rate in reversing stroke symptoms is about 33% but even using it wisely, there is a bleeding potential of 6%. The key is to find the right situation that minimizes bleeding and maximizes potential success. The major limitation to the use of TPA is time. The longer that brain tissue has been deprived of blood supply, the greater the chance that bleeding will be a complication. Three hours is the magic number from onset of symptoms to when the risk of bleeding becomes unacceptable (recently, that number has been increased to 4 ½ hours in some patients but there is still some controversy). In those three hours, the patient or their family has to recognize that a stroke has occurred, get to the hospital, have the diagnosis of stroke made, blood tests and CT scans done, the drug mixed and administered. The major stumbling block is the delay in getting to the hospital. Patients always hope that their symptoms resolve and by waiting, the treatment window sometimes slams shut.
Sometimes statistics are ignored only because the risk/reward leans strongly to the reward side of the equation. The reason most lacerations are sutured is too speed healing and achieve a better cosmetic result. The longer a cut is left open, the higher the potential risk of infection. Some research suggests that the infection rate spikes at 6-12 hours but it’s the location of the laceration that makes the difference. An old wound on the leg could be cleaned out well and left to heal on its own but the same cut on the face might be sewn shut because the risk of cosmetic deformity would outweigh the infection risk.
And then there’s the 800 pound gorilla in the room. When a patient presents with chest pain, statistics are hard to come by to decide whose story leans more towards the pain being angina and a potential heart attack disaster and who might have esophagus inflammation and heartburn. It may be the art of the history, the asking questions to understand the quality of pain and learning about the patient’s risk factors of high blood pressure, high cholesterol, smoking, diabetes and family history that might sway the doctor to worry more about the heart. It might be the art of the physical examination that finds an abnormal heart sound that leans towards angina or an early rash that could diagnose shingles. It might be the art of reading the EKG or of ordering and interpreting blood tests appropriately. Who needs hospital admission, who needs what test and who gets to go home depends upon skill, experience and intuition.
Players and managers often have gut feelings that motivate their decision making on the playing field. When they don’t follow the book, the downside is perhaps a lost game. In medicine, guidelines provide direction for patient care. Ignoring them may be appropriate but being cavalier may have more deadly consequences than a strike out. The art and science of medicine blend because every patient visit is unique and a single cookbook recipe will not fit every situation. The good doctor knows when to follow the guidelines and when to recommend that they be bent but bending should be the exception.