Tag: medical

Posted in Psychology & Medicine

Sleeping Sickness

Posted on by Jinavie

A woman travelling in Africa is bitten by what appears to be a mosquito. She swats the insect and keeps on going about her journey. The next week, she finds that she has a small nodule where she was bit. She is also feeling slightly unwell, with fever and fatigue. Over the following two weeks, her fever worsens (coming and going intermittently) and she notices large lumps along the back of her neck. By this stage, she is experiencing muscle and joint pain as well. After returning home from her trip, she finds that her symptoms have not resolved. On top of her fever and pains, she begins experiencing headaches, mood swings, lethargy, confusion, clumsiness, delayed response to pain, sleepiness during the day and insomnia at night. She begins to worry that something is wrong, but she believes that it is a bad flu and does not see a doctor. Her symptoms worsen with time (sleeping up to 15 hours a day), until one day, she falls asleep and does not wake up. She is taken to a hospital, where it is discovered she is in a coma. She dies within a week.

This is the typical presentation of sleeping sickness, also known as human African trypanosomiasis. It is an infectious disease caused by a protozoan parasite called Trypanosoma brucei (comes in two types: T. brucei rhodesiense (East African type) and T. brucei gambiense (West African type)), which is transmitted by tsetse flies – a bloodsucking fly endemic to sub-Saharan Africa (there are also case reports of sexual transmission between people). When infected, the parasite rapidly proliferates in the patient’s bloodstream. It is not detected by the host immune system, thanks to a surface protein called VSG. This allows it to spread through the patient swiftly and silently via the circulatory and lymphatic systems. The early symptoms (intermittent fever, rash, lymph node enlargement), typically presenting about a week or two after infection, are due to the parasite spreading through the blood and lymph. As the infection spreads, the parasites begin to invade the central nervous system (although in the West African type of the disease, patients often die from the toxic effects of the parasite replicating in the blood before they reach this stage).

As the infection spreads through the CNS, it causes the neurological symptoms described in the case. The sleepiness (from where the disease gets its name from) worsens as the disease progresses, with patients finding it difficult to wake up in the morning, even sleeping for over 20 hours. The sleepiness is caused by a chemical called tryptophol, which is produced by the parasite. Essentially, the neurological symptoms appear as if the person’s brain is slowing down, until they fall into a coma, resulting in death without treatment (usually within 2~3 years since the infection).

Sleeping sickness is invariably fatal unless treated early. Once the patient reaches the second stage (neurological phase), treatment becomes very difficult. The current first line treatment is a drug called melarsoprol, which is a form of arsenic. Because of its toxic nature, it is extremely dangerous and there is around an 8% chance of the patient dying from side effects. Fortunately, there are less dangerous and more effective treatments such as eflornithine (which only works for the West African type) being developed.

Posted in Psychology & Medicine

Hypothermia

Posted on by Jinavie

A person’s body temperature is always maintained between 36.5~37.5°C. This is because enzymes, which are crucial in all physiological reactions in the body, work most efficiently at this temperature. As physiology is essentially a series of chemical reactions, it is heavily dependent on temperature. If the temperature falls, chemical reactions occur slower and vice versa. When body temperature falls below 35°C, metabolism becomes too slow and it poses a risk to the person’s health. This is known as hypothermia.

How does hypothermia affect the body? Hypothermia is categorised into three classes depending on the severity.

  • Mild hypothermia (32~35°C) leads to the slowing of bodily functions, tremors and difficulty in walking. The patient’s speech is impeded and other neurological symptoms such as decreased judgement skills and confusion start to appear. Also, blood pressure, pulse and breathing rate rise.
  • Moderate hypothermia (28~32°C) causes paralysis of muscles and extreme fatigue (they may complain of being sleepy). As blood (carrying heat) is rerouted to major organs, the skin (especially lips and extremities) become white or purple and very cold. Neurological symptoms worsen with amnesia, memory loss, severe confusion and delusion beginning to show. As sustained hypothermia leads to the tremors stopping, one should not take the lack of tremors as a good sign. Heart rate becomes irregular and arrhythmia may occur.
  • Severe hypothermia (20~28°C) leads to chemical reactions becoming so slowed that physiological functions that support life decline dramatically. Heart rate, blood pressure and breathing all lower to dangerous levels and the heart and lungs may stop functioning. As the patient’s major organs begin to shut down, they enter a state of unconsciousness and eventually, clinical death.

As you can see, hypothermia is a highly dangerous situation that can kill. There are some other fascinating facts about hypothermia.

20~50% of hypothermia death cases are associated with paradoxical undressing. This is a strange phenomenon where the person begins to take off their clothes due to confusion and a lack of judgement from the hypothermia. One theory suggests it is related to the cold damaging the hypothalamus (which controls body temperature), causing the brain to think that the body temperature is rising. Whatever the reason, it is extremely dangerous as it worsens the hypothermia.

As explained above, severe hypothermia leads to death. But interestingly, hypothermia also protects organs. This is why organs for transplanting are transported in ice. Similarly, there are examples of people who “died” from hypothermia recovering with no brain damage. Because of this, medical professionals traditionally say: “they’re not dead until they’re warm and dead”. In fact, if there is something wrong with the patient’s circulation and there is risk of damage to their organs (such as in surgery), sometimes the patient’s body temperature is forced down with ice water injections and cooling blankets, known as protective hypothermia.

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Posted in Psychology & Medicine

ICU Syndrome

Posted on by Jinavie

ICU stands for intensive care unit and is the place where patients are sent after an operation to stabilise and recover under supervision. ICU patients commonly have a very unique and strange post-operative experience.

ICU syndrome is a type of delirium where the patient experiences severe anxiety, fear, hallucinations or delusions. Although the cause has not been determined, it is likely related to post-op stress, the segregation and loneliness in the ICU room and confusion from coming out of anaesthesia. This is especially the case if an emergency situation led to the surgery being longer than expected or resulted in additional surgery, causing extreme confusion in the patient.

A patient suffering from ICU syndrome tends to be extremely excited and unstable. They may develop intense paranoia or distrust (especially against medical professionals), which can lead to fits or dangerous acts such as pulling out cannulas and lines. A friend or loved one talking calmly to the patient has a great effect in helping the patient overcome the delirium. Therefore, allowing the family to visit to keep the patient company and calm is an effective way to prevent ICU syndrome. However, if the situation spirals out of control, a sedative or anti-psychotic may need to be administered.

A study states that about 25% of patients admitted to the ICU suffer from ICU syndrome. It is one of the most common causes of delirium and any patient can get it (elderly patients are more likely to). Interestingly, there is a theory that medical professionals are more likely to suffer ICU syndrome after an operation.
Nowadays, the term ICU syndrome or ICU psychosis is discouraged and is instead grouped under delirium (which is an actual psychiatric disorder, not just a general term).

Posted in Psychology & Medicine

Flatline

Posted on by Jinavie

When people think of the word “flatline”, they immediately visualise a medical crisis where a patient is lying unconscious, with doctors and nurses shouting out medical terminology while administering drugs, all to the suspenseful music and apathetic monotone and single horizontal line on the ECG machine. The doctor then shouts “Clear!” and proceeds to shock the patient with two paddles. This is repeated until some structures appear on the ECG, symbolising that the crisis has been resolved.

Of course this is a scene from a typical medical drama. Television shows, especially medical ones, are notorious for sacrificing medical accuracy for the sake of drama and tension. The “flatline” is the most cliché, repeated mistake made by almost every medical television show ever made.

The proper terminology for a flatline (a colloquial term), is asystole. This means that there is no systole, or contraction of the heart. An ECG (electrocardiogram) measures electrical signals in the heart, and in asystole there is insignificant amounts of electric activity, and the classic QRS complex is not seen. In this state, the heart is not pumping any blood and is electrically silent, meaning that the patient is clinically dead.

When asked how to treat this condition, the majority of people (even medical students) will shout “Shock!” or “Defibrillate!”. Defibrillation is the administering of an electrical shock to try “reboot” the heart, and correct the fibrillation – the chaotic electrical signal interfering with the normal, rhythmic electrical activity. Unfortunately, this is completely wrong yet so often depicted on television and films.
As asystole is a state of no electrical activity, there is no fibrillation to remove, nor is there anything to reset. Defibrillation in this state may even cause harm, causing tissue damage and lowering the chance of survival.

The correct treatment is injecting adrenaline (epinephrine in the U.S.A, atropine may be administered also) and CPR. Unfortunately, asystole is a condition that cannot be reversed, unless the heart somehow restores its own electrical activity. CPR merely keeps the patient’s perfusion going to preserve the organs for a longer time. Ergo, asystole signifies certain death, especially after 5 minutes where the heart will not respond to any drugs or electric shocks. In fact, asystole is one of the conditions required for the certification of a patient’s death.

Another related example of a (potentially fatal) misrepresentation of medicine in the media is the adrenaline injection. As mentioned before, this is the treatment for asystole. However, it is administered intravenously (into a vein) and never directly into the heart as in Pulp Fiction. This is more likely to kill the patient than save them, as the heart muscles could be damaged and delicate coronary arteries may become ruptured.

So why is it that the media continues to depict such blatant errors, that set a “common sense” that affect even medical professionals? This is most likely due to the audience wanting to see a dramatic scene, in a gripping life-or-death situation with drastic, powerful action. For example, the audience would much rather see the use of paddles or a giant needle being stabbed into the patient than seeing continuous CPR with no showy movements.

The next time you watch a medical television show, count how many times the doctors try to defibrillate a flatline.

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