Intensive care medicine

Intensive care medicine, also known as critical care medicine, is a medical specialty focused on patients with life-threatening conditions. These patients are often seriously ill, at risk of death, or recovering from dangerous medical events. This field provides essential services like life support, resuscitation, and invasive monitoring. It also manages end-of-life care when necessary. Doctors who specialize in this area are called intensivists or critical care physicians.

Because the work is so complex, it relies on multidisciplinary teams. These teams include doctors, nurses, pharmacists, physical therapists, and respiratory therapists. They work together in specialized areas called intensive care units (ICUs) or critical care units (CCUs).

Patients enter the ICU when their medical needs exceed what a general hospital ward can provide. Common reasons for admission include cardiovascular instability, such as high or low blood pressure. Other causes include sepsis, cardiac arrhythmias, or post-cardiac arrest syndrome. Patients may also need the ICU if they have respiratory compromise and require a ventilator. In some cases, multiple organ dysfunction syndrome occurs, which is the cumulative effect of several organs failing at once. Major surgery can also require the close monitoring provided by an ICU.

ICUs are organized in different ways depending on the hospital. There are two main structures: closed and open units. In a closed unit, a single intensivist takes the primary role for every patient. In an open unit, the primary physician for each patient may be different. While open units are common in the United States, many large academic centers use closed units. Current evidence suggests that closed units often provide better patient outcomes. Some hospitals also use intermediate structures that fall between these two models.

Many hospitals create specialized units to meet specific medical needs. A coronary intensive care unit (CCU) focuses on heart disease. A neonatal intensive care unit (NICU) cares for newborn babies. Other examples include the pediatric intensive care unit (PICU) and the neuroscience critical care unit (NCCU). There are also units for surgery (SICU), medical needs (MICU), and trauma (STICU). Even the emergency department may have its own ICU area. These different types of units allow staff to use the specific resources required for different patients.

Monitoring is a vital part of intensive care used to track a patient's condition. There are two main types: noninvasive and invasive monitoring. Noninvasive monitoring is painless and does not puncture the skin. It includes checking vital signs like heart rate, temperature, and breathing rate. Tools like pulse oximetry monitor oxygen levels, while an electrocardiogram (ECG) tracks the heart's electrical rhythm.

Invasive monitoring is more direct and often provides more accurate data. It may involve an arterial line to measure blood pressure or a central line for drug infusions. These methods can be uncomfortable because they require puncturing the skin.

Treating patients in the ICU requires a system-by-system approach. Doctors manage the airway using tools like laryngoscopy and endotracheal intubation. For the cardiovascular system, they might use temporary cardiac pacing or an intra-aortic balloon pump. If the lungs fail, mechanical ventilation assists breathing through a tube. For kidney issues, doctors may use hemofiltration. They also use various drugs, such as inotropes to support the heart or sedatives to keep patients comfortable.

This intensive management helps stabilize the body's most important functions.

The history of intensive care shows how much medical science has advanced. In the 1850s, Florence Nightingale moved the sickest patients closer to nursing stations to improve monitoring. In 1923, Walter Dandy created a specialized three-bed unit at Johns Hopkins Hospital. A major turning point occurred in 1952 during a polio epidemic in Copenhagen. Dr. Bjørn Aage Ibsen used positive pressure ventilation to help patients with respiratory paralysis. This change helped mortality rates drop from 90% to approximately 25%. In 1953, Ibsen established the world's first ICU in a converted classroom.

Despite the advanced care, ICU patients face specific challenges. One common issue is ICU delirium, which was formerly called ICU psychosis. This syndrome occurs when patients in unfamiliar, monotonous surroundings develop hallucinations. They might hear machine noises as voices or see walls quivering. There is also a link between the volume of patients and the quality of care. For example, hospitals with 401 to 617 mechanically ventilated patients annually had an adjusted mortality rate of 14.5%. In contrast, hospitals with only 87 to 150 patients annually had a mortality rate of 21.2%.