passing out

Monday, April 3, 2017

Fans watch where the action is but video cameras record all, including what happens well away from the play. Low motion instant replay is usually saved for highlights or controversial plays, but for Philadelphia Flyer Michal Neuvirth, those cameras captured him collapsing in his goal, 100 feet away from the puck Without warning, Neuvirth fell to the ice and remained motionless for a few minutes until he gradually wakened and was rushed to the hospital. He was observed overnight, and with initial testing being normal, he was discharged home, no doubt to be poked and prodded to find out just what happened.

Passing out is never normal. At its very basic, the purpose of the body is to protect the brain at all costs. Brain cells need very little to function, oxygen, sugar and that’s about it, but it takes a complicated factory to deliver those two basic goods. A person needs to be able to breathe to get air into the lungs, where oxygen needs to be extracted and tacked onto red blood cells. The heart pumps those cell through arteries to the brain. Glucose is added to that oxygen supply when digestive system extracts glucose from food and dumps it into the bloodstream.

With those two building blocks, a person will be awake if two structures in the brain are working. The reticular activating system, the on/off switch in the brainstem, needs to be in the on position and at least one hemisphere of the brain needs to work. Blood supply needs to be cut to one or both of these parts of the brain for a person to become unconscious.

It may be a true emergency when a patient has a syncopal event, meaning that they passed out. If the patient remains unconscious, treatment and diagnosis happen together. Blood is tested for low blood sugar (hypoglycemia), a dose of Narcan might be given in case the person overdosed on a narcotic and an EKG with a heart rhythm strip is done, looking for a heart rhythm disturbance. Most often, though, the patient is awake by the time they are seen by the doctor and the detective work begins to look for clues as to the reason why the patient passed out, make certain that no disaster has occurred and hopefully prevent another passing out episode.

Passing out often is a fluid delivery problem. Cardiac output measures how much blood the heart pumps per minute. Enough output and the blood pressure is maintained to push blood uphill to the brain. The cardiac output formula is relatively simple:

      Cardiac output = Stroke volume x Heart Rate

Output equals how much blood is pumped per heartbeat multiplied by how often the heart beats per minute, and is a measure of how effective the heart is in meeting the body’s and the brain’s demands for energy. Problems may exist with the heart rate and rhythm or with the red blood cells and fluid. Anemia (low red blood cell count) or dehydration (decrease fluid in the body) may decrease how much blood is pumped per heartbeat. A heart that beats too slow, too fast or not at all, will also decrease cardiac output.

Some problems are not very serious, like a vasovagal episode, where the heart slows and blood vessels dilate because a noxious stimulus that stimulates the vagus nerve. Imagine a medical student fainting when he sees his first operation or a patient who passes out because of pain. Other causes can be life threatening, like a massive pulmonary embolus or blood clot to their lung (25% of patients with PE present with sudden death), a structural problem with the heart or a major electrolyte crisis in the body.

ESPN reported that Mr. Neuvirth had been recently ill recently with a virus infection and perhaps his syncope was due to dehydration. Standing in full equipment can make a goalie sweat up a storm…but while dehydration is a possibility, the big worry is whether Mr. Neuvirth had a heart rhythm abnormality, an electrical disaster like ventricular fibrillation nor ventricular tachycardia. When the bottom half of the heart does not get an organized electrical signal, it can’t squeeze in a coordinated fashion, it can’t squeeze, blood doesn’t flow through the body, including the brain, and the patient can pass out. V fib and V tach may be the cause of sudden death.

Since the patient is usually not on a monitor when the event happens, and if no other easy diagnosis can be found to explain the syncope, admission to the hospital to watch the heart rate and rhythm is usually the safest plan. Sometimes a clue can be found on the EKG or during observation, but often not. The patient is usully discharged home with no solid answer but with the expectation that further tests might need to be done. Since people live in the real world and not a hospital bed, people can have their hearts monitored in the real world for durations of 1-2 days or even months at a time. Every heartbeat can be recorded and analyzed fro potential problmes.

The treatment of syncope depends on the cause but from a practical standpoint, sometimes the cause is never found. The question then becomes, what advice should be given to the patient regarding activity. There is no right answer when the diagnosis is not known. In the ER, the unknown syncope decision is easy; the patient needs to stay in the hospital to be monitored. But once the dust has settled, it’s a risk-reward discussion between doctor and patient to decide when it’s safe to return to full activity, whether that’s work, driving a car or playing goalie in the NHL.

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blood clots

Monday, August 11, 2014

In August, a Philadelphia sports fan should be thinking about the Eagles and the Phillies but not necessarily the Flyers…okay, perhaps not the Phillies either, so it would have been easy to miss the news in the City of Brotherly Love, that Flyer defenseman, Kimmo Timonen, was hospitalized in Finland for blood clots in his leg and lung. The 39 year old was supposed to play an important role for the Flyers in the coming season, but team General Manager Ron Hextall was uncertain whether he could play: “This could be a long term thing…Could he play next season? I don’t have an answer to that.”

The answer begins with the treatment for DVT, deep venous thrombosis or blood clot in a vein, and PE, pulmonary embolism or blood clot in the lung. Anti-coagulation or blood thinning is the treatment of choice for both DVT and PE and while on that treatment, Mr. Timonen will not be playing hockey. By interfering with the body’s ability to clot blood, minor injuries can become major disasters, especially in hockey where falls and body contact are routine parts of the game. A minor bump to the head can cause lethal bleeding in the brain. A blow to the chest or abdomen can cause uncontrolled bleeding and shock if the body cannot mend itself. The big question to be asked is how long does he have to be on blood thinners? And that is where the science of medicine is not quite as precise as we have come to expect.

There are a few reasons why a blood clot or thrombus might form. The big three categories are vein injury from trauma, blood stasis and problems with the blood clotting mechanism. If the body is immobile, there is less muscle activity to squeeze blood back to the heart and stagnant blood tends to clot. Patients who are bedridden due to stroke or surgery (especially after pelvis, hip or leg operations) and those that have casts in place are at risk, as are people who sit in an airplane or car for hours. Decreased blood flow from the legs may also occur in obese people and can also be seen in pregnancy where the enlarged uterus compresses veins in the pelvis. Underlying medical problems can increase the risk of blood clot formation and range from genetic predisposition, to cancer, to smoking and the use of birth control pills.

DVTs are common but the big complication occurs when the thrombus breaks off and embolizes or travels through the heart and gets lodged in the lung arteries. More than 600,000 people are diagnosed with a PE every year in the US and the death rate is about 25%, but those numbers may significantly underestimate the problem. Based on death studies, there may be more than double that number and the diagnosis of pulmonary embolus often occurs autopsy. When a PE occurs, it affects the ability of the lung tissue to transfer oxygen from the air in to the blood stream and depending upon the amount of clot, the symptoms may be mild (sharp chest pain and mild shortness of breath) to collapse and sudden death.

The diagnosis is always in the back of the doctor’s mind to at least be considered when caring for people with shortness of breath. The diagnosis is entertained based upon history, physical examination, clinical suspicion and risk factors. It is confirmed in a variety of ways depending upon the clinical situation and the patient’s stability. Often, it may include, EKGs, blood tests, ultrasounds and CT scans.

For most people the treatment is anticoagulation, the use of medications to thin the blood. There are a variety of choices, depending upon the patient’s situation but most involve a combination of heparin injections to immediately thin the blood while also taking Coumadin by mouth. It takes a few days for Coumadin to reach effective blood levels, so dual therapy often occurs. Newer anti-coagulation drugs have been developed and in the past few months, Xarelto (rivaroxaban) has been approved as a single step oral treatment for PE. But in critical situations, emergency surgery may be required to remove or dissolve blood clots in the lung.

With that background, the question remains. How long should treatment last? For the first DVT or PE, anticoagulation is recommended for 3 months, as long as there is no underlying reason to consider longer therapy. Imagine a cancer patient or one who has an abnormal blood clotting disorder. For recurrent clot, the recommendations are less clear and consideration may be given to life-long treatment. The duration of therapy recommendations are more than a little vague for those patients.

This is the second time around for Mr. Timonen with clots. In 2008, he developed a DVT after being hit by a puck in the foot. Now the questions that face him and his doctors include whether that first DVT was due to trauma and does not count in deciding how long the anticoagulation should last. And they need to decide what caused this episode of DVT and PE and whether there should be a search for any underlying risk factor. And that leads to the question posed by the Philadelphia general manager as to whether Mr. Timonen will play in the coming NHL season that begins in about a month. And the answer is…not anytime soon.

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