Critical Care

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This section is large (don't we all love hurting out heroes!) so has been subdivided. The Vital Signs section (below, in this page) contains an outline of normal and abnormal pulse and respiration rates, blood pressure and temperature, along with a description of those occasions when these go wrong eg hypothermia, blood loss etc. This page also includes a description of Shock. On a separate page, the Injuries section describes more specific injuries, such as gunshot wounds, and yet another page tells you all about the various Tubes stuck into a hapless patient in Intensive care.

Both sections were written by (NAME DELETED) RN, CRNI

Disclaimer: Please note that the following are generalizations only. Every situation is different, with too many mitigating factors to include here. I have tried to list the most common fanfic injuries and medical conditions, with their signs and symptoms (s/s), best and worst case scenarios, probable treatments, and recovery times for each. If I have insulted anyone by being too basic, I apologize; fanfic writers come in all occupations and ages, so it was difficult to know where to start. Also please note that this is not a do-it-yourself emergency medicine textbook; it is intended only as a resource for writers to lend some authenticity to the medical details in their writing.

Vital Signs

Vital signs, or "Vitals" (as in "Nurse!!! What are his vitals?") are a common benchmark of health and consist of a person's temperature, blood pressure, pulse and respiration rate. There are ranges of what is considered "normal". Below are the normal ranges, and the medical conditions/injuries that affect them:


Normal body temperature is 98.6 degrees F (37.4 C) but it is not unusual for that to vary by a degree F higher or lower from individual to individual. It is measured orally, axillary (under the arm), and rectally ('nuff said). The most accurate measure of temperature however is the core temperature. This is determined in critically ill patients by means of a Swan Ganz catheter threaded into the chambers of the heart (the catheter takes other readings as well which will not be discussed here). Forensic pathologists like Scully would also take core temperatures, as this is one of the easier methods of determining how long a victim has been dead. She would take the temperature by inserting the spike-like thermometer through the skin and into the body, usually in the area of the liver.

High temperatures (aka fever or pyrexia): can be caused by infection, dehydration, or hyperthermia (often seen in sunstroke, heat stroke) and can reach to 106 degrees F and higher. Such high temperatures, if sustained for more than a few hours, can cause severe and irreversible brain damage or death. Treatment: Treatment is by antipyretics such as aspirin, ibuprofen and acetaminophen, and sometimes by cooling blankets (cold water forced through a thin plastic mat under the patient's sheets), or sponging the body with tepid water. Rubbing alcohol is no longer used for this as the fumes can be harmful. It is also treated by reversing the cause of the fever, such as antibiotic therapy in the case of infection, and IV fluids in the case of severe dehydration.

Low Temperatures (aka hypothermia): can be caused by shock, anemia, dysfunction of the hypothalamus and prolonged exposure to cold. Severe hypothermia (like Mulder in Colony/End Game) from prolonged exposure to cold can cause temps as low as 88-93 degrees F. Obviously, the lower the temp and the longer it is sustained, the more grave the outlook is for the patient (unless they also happen to have a retrovirus!) Treatment: Treatment is aimed at slowly warming the individual, in water or with heated blankets, as well as warmed IV fluids. It is necessary to do this slowly to avoid injury to the skin and other complications. Severe hypothermia can cause enough damage to the skin for gangrene to occur, which can result in amputation of the affected area (usually hands and feet). It can also cause life-threatening cardiac arrhythmias (irregular heart beats). In rare cases it can cause a condition know as Disseminated Intravascular Coagulation (DIC), a very complex and nasty condition (trust me) in which the patient's blood clotting mechanism is disrupted. As a result, the patient bleeds from every opening in his body, including needle puncture marks, surgical incisions, as well as the natural openings like the mouth, ears, nose, eyes, etc. This condition is very difficult to treat and death is often more common than recovery.

Blood Pressure

Blood pressure measures the force of the blood circulation in the body and consists of two numbers, the systolic (upper) and the diastolic (lower). Normal Blood pressures in adults range from roughly 100-140/60-80. Generally, the younger and more physically fit individual will be on the low end of that range, such as 110/64.

High blood pressure (hypertension): High BP (160/100 and above) can be caused by excitement/fear, cardiovascular disease, head injuries and renal (kidney) failure. Pain can effect the BP, usually making it go up, but sometimes making it go down. Treatment: For temporary emotional conditions, no treatment is necessary. For other conditions, it is treated with antihypertensive medications and sometimes with diuretics (to decrease retained fluids in the body). Untreated chronic high BP or sudden episodes of very high BP (200/120 and up) can cause strokes, nosebleeds, and retinal hemorrhages (which can lead to blindness).

Low Blood Pressure (hypotension): Low BP (80/50 and lower) is caused by shock, blood loss, dehydration and cardiac failure. A severely low BP (40/0 and lower) indicating profound shock or body failure can be irreversible, leading to death very quickly. See more detailed section on Shock below. Treatment is with IV fluids, volume expanders, blood (in the case of blood loss) and IV medications such as vasopressors, which constrict the blood vessels in the extremities and force it into the organs. These medications are very powerful and can have serious and lasting side effects.


The heart rate, strength and rhythm is determined at its most basic by taking the pulse. The normal pulse is 60-100 beats per minute, depending on age and physical condition. A runner like Mulder would have a normal pulse in the low 60's and possibly in the 50's.

Rapid Pulse (tachycardia): the heart rate will rise with fear, pain, excitement, exercise, fever, shock, blood loss, cocaine and amphetamine use, and cardiac dysfunction to 120 beats and higher, sometimes as high as over 200 in cardiac arrhythmias (for extremely short periods of time - obviously, the heart cannot sustain this rate for long before failing altogether). A "thready pulse" is weak, very rapid and irregular in rhythm, and is a grave sign of serious shock. Treatment: As with BP, temporary increases in rate happen naturally and resolve naturally. Chronic tachycardia due to heart dysfunction is usually treated with digoxin and other drugs to slow and strengthen the heart's contractions. Other treatment, such as when the tachycardia is caused by Shock, will be discussed below.

Slow Pulse (bradycardia): the heart rate is normally slower in sleep and when a person is relaxed or meditating. It becomes abnormally slow in heart malfunction (usually in a condition called heart block where the heart's "built-in" pacemaker isn't working right and a mechanical pacemaker needs to be inserted). It is also abnormally slow in patients with head injuries and in overdoses of narcotics, barbiturates, sedatives and alcohol. Treatment: depends on the cause, and usually involves a temporary or permanent pacemaker.

Respiratory Rate

The normal resting respiratory rate is 12 - 20 breaths per minute, with clear lung sounds.

High Respiratory Rate (tachypnea): The respiratory rate goes up with exercise, fear, shock, lung disease, pain and fever. Treatment: Except for lung disease, these all resolve naturally such as when the person rests, or the fever goes down. Lung disease is treated with medication, inhalers and sometimes with oxygen.

Low Respiratory Rate: The rate goes down in sleep, with narcotic or barbiturate overdose, and in severe head injuries. Usually there are no ill effects for a sleeping or unconscious person with a rate as low as 9 or 10. Lower than that, and the person can become hypoxic (too little oxygen), which can show up as cyanosis (blue color of the fingers, toes and lips). Severe hypoxia can lead to brain damage. Treatment: Treatment is usually supportive; that is, providing the patient with extra oxygen until the condition causing the hypoxia is resolved. When the patient is unable to breathe spontaneously on his own, an endotracheal tube is inserted down the throat into the trachea, and connected to a ventilator (aka respirator) which forces oxygen into the patient's lungs at a set rate (Mulder in End Game, Scully in One Breath).

Additionally, there are certain patterns of respiration which are grave signs. One is called Cheyne-Stokes. In this pattern, a person will breathe rapidly, then more slowly until he doesn't breathe at all (a condition called apnea) for 30 or more seconds. Often this is a sign of impending death. Another is called Kussmaul's respirations. These are very deep, very slow respirations seen in severe head injuries and coma.


Since shock can occur with so many conditions and since it comes up in fanfic a lot, it is included here. There are many kinds of shock:

Treatment and severity depend on the type of shock. In general, patients are placed lying down with their legs higher than their heads and chest (in the hospital sometimes known as Trendellenburg position, and facilitated by "shock blocks" on which the foot of a non-electric bed may be raised). This position causes the blood to circulate better to the brain, heart and lungs, where it is needed most. Note: This is not the case in head injuries, when an effort is made to lessen the pressure and blood flow to the brain.

The latter two kinds of shock, more severe and more likely to appear in fanfic, will be discussed in detail.

Hypovolemic Shock

Hypovolemic shock is seen in severe dehydration, widespread burns, and blood loss. Signs and symptoms and treatments are as follows:

Severe Dehydration: Some reasons for severe dehydration include high fever, protracted thirst (2-3 days without water or other fluids) and severe vomiting and diarrhea. When any of these is present in addition to exposure to the sun or heat, the risk of severe dehydration multiplies. Signs and symptoms include: rapid, sometimes thready pulse; rapid respirations, low (sometimes very low) BP, weakness, fainting, pallor, lack of urine output and finally coma. Treatment consists of giving large amounts of fluids. Since the patient may not be conscious and therefore can't swallow, or has severe vomiting, the fluids must be given intravenously, through a needle or tube into a vein. Sometimes these needles are peripheral (into a hand or arm), and this is usually what is portrayed on TV. But most often in real life the peripheral lines are replaced as soon as possible by central lines, larger tubes inserted into a major vessels by a surgeon. The reason for a surgeon to insert such a line is that the patient often has very low blood pressure, making starting a peripheral IV line difficult or impossible. Also, a central line is larger and can deliver fluids more quickly and surely than a peripheral line. The fluids usually given are 0.9% Normal Saline, which most resembles the body's natural fluids, or Lactated Ringers, a solution which includes electrolytes (chemicals the body needs in precise quantities). With fluid replacement, hypovolemic shock can resolve quickly, over a few hours.

Widespread burns: Burns cause dehydration because the skin, which helps to hold in body fluids, is no longer intact and body fluids seep out. Fluids are replaced in the same way as above, except that central lines are always inserted. Treatment also includes care for the burns (usually nasty and extremely painful) and antibiotic therapy, since burns become infected very easily.

Blood Loss: Blood loss is usually, but not always, seen. Bleeding almost always appears worse than it is. Hands, feet and heads tend to bleed profusely because they have many blood vessels, but usually the amount of blood lost from a simple cut, while frightening, is not enough to send a person into shock. The bleeding can be controlled by keeping firm pressure on the cut (but snap on the latex first!). If arterial bleeding is involved, however, or if the bleeding comes from a major vessel, it is very serious. Arterial bleeding can be diagnosed by its bright red color (as opposed to the darker red venous bleeding) and by the fact that it pumps rhythmically, rather than just flowing out. Bleeding from a major vessel always produces large amounts of blood flow which can't be controlled merely with pressure. These major vessels are usually located in the chest or abdomen, where applying pressure is difficult or impossible anyway.

This may be a good time to bring up tourniquets. Tourniquets are not often used. The tourniquet will cut off all circulation to a limb, and may cause such severe and irreparable nerve and tissue damage that the limb will have to be amputated. Therefore they are used only when it seems sure that it is the only way to save the wounded person's life. This is usually in the field - at the scene of the accident or when any other kind of medical attention is too far away to help. Even then, they should be loosened periodically to restore circulation to the limb, even if it means that the patient bleeds for short periods of time.

As mentioned above, sometimes blood loss doesn't show. "Internal bleeding" is blood loss from a ruptured vessel or organ but the blood is contained within the body. Usually this happens in the abdomen, and is characterized by s/s of shock and increasing pain and rigidity of the abdomen. It can also happen in the chest, causing a hemopneumothorax (see Broken Ribs section). Also, the fracture of a long bone such as the femur (thigh) can result in as much as a two pint (1 liter) loss of blood into the tissues of the upper leg, which might not be apparent for some time.

Blood loss is not significant if it is only a pint (500 ml) or so (this is the amount that is commonly taken when a person donates blood). That much blood loss could cause pallor or dizziness, but rarely shock. The loss of two to four pints causes the other signs and symptoms of shock to appear - significant blood pressure drop, rapid pulse, fast respiratory rate, sometime a feeling of not getting enough air, tremors, extreme pallor, sweating, anxiety and loss of consciousness. Loss of four or more pints usually causes profound shock and requires immediate blood replacement.

In humans are four blood types - A, B, AB, and O. Each of these also is either positive or negative for the Rh factor, thus A+, O-, and so on. In addition to the Rh factor, there are dozens of other factors and antigens in the blood. When a person suffering from profound shock from blood loss is brought into an ER, the first thing done is a "type and crossmatch" for a certain number of units of blood. This is a test which determines the victim's blood type and crossmatches a certain number of units of donated blood for the factors which most closely resemble that of the victim's blood. The consequences of any blood transfusion can be grave today, but a transfusion reaction can be rapidly fatal. Typing and crossmatching doesn't take a long time. Unless the victim is within minutes of death and there is some delay in obtaining successfully crossmatched blood, untype and matched blood is not given. In such dire emergencies, type O blood may be given, especially O- (given to Mulder in Beyond the Sea, unless that's his actual blood type. I don't know if we know his blood type yet.)

The first thing that would happen in the ER after the blood sample was taken for type and match would be starting one or more IV lines (IV lines started in the field are usually replaced upon entering the ER) and giving IV fluids "wide open" (as fast as they will run in). Blood would probably be matched and ready to give within twenty minutes or less. In the meantime, the source of the bleeding would be found and attempts made to stop it - surgically (sewing up a ruptured artery) or by clamping the vessel off. Vasoconstrictors might be given to limit the flow of blood and the vital signs carefully monitored. By then the blood would have arrived from the lab and would be given as fast as possible. Blood infuses more slowly than other fluids (it really is thicker than water). In severe bleeding with a "crashing" patient, the plastic blood bag is sometimes squeezed in the nurse's hand to literally force the blood into the patient's veins. A massive transfusion is 15 or more pints in 24 hours. Once the patient was stabilized (the vital signs improved and no longer in imminent danger of death) they would be taken to the Operating Room if necessary for surgery, or to the ICU for close monitoring and more transfusions.

In hypovolemic shock, once the patient's vital signs are stabilized and the fluids/blood replaced, the patient makes fairly rapid progress (from the shock, at least - the cause of the shock may take longer to correct).

Septic Shock

Septic shock is caused by a virulent widespread infection. The body temperature is not necessarily a good diagnostic indicator, since sometimes the temp will go down in septic shock, even though fever is generally thought of as a sign of infection. The pulse becomes rapid and thready and the blood pressure crashes. All these events occur very quickly, often without other signs of what may be causing the problem. Tardiness in making the diagnosis often costs the patient his life. Treatment: In cases of septic shock, blood transfusion is of no use (indeed, blood transfusion may be the source of the infection) and IV fluid administration is less important than determining the organism causing the infection and starting the correct IV antibiotic to kill it. Unfortunately, all this takes time - even the correct antibiotic can take days to effect a change in the patient's condition. Because the process takes so much longer than merely blood or fluid replacement, septic shock is extremely serious and often fatal.

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