Intensive care medicine, usually called critical care medicine, is a medical specialty that deals with seriously or critically ill patients who have, are at risk of, or are recovering from conditions that may be life-threatening. It includes providing life support, invasive monitoring techniques, resuscitation, and end-of-life care. Doctors in this specialty are often called intensive care physicians, critical care physicians, or intensivists.
Intensive care relies on multidisciplinary teams composed of many different health professionals. Such teams often include doctors, nurses, physical therapists, respiratory therapists, and pharmacists, among others. They usually work together in intensive care units (ICUs) within a hospital.
Scope
Patients are admitted to the intensive care unit if their medical needs are greater than what the general hospital ward can provide. Indications for the ICU include: blood pressure support for cardiovascular instability (hypertension/hypotension), sepsis, post-cardiac arrest syndrome, certain cardiac arrhythmias, airway or ventilator support due to respiratory compromise, the cumulative effects of multiple organ failure (more commonly referred to as multiple organ dysfunction syndrome), or close monitoring or intensive needs following a major surgery.
There are two common ICU structures: closed and open. In a closed unit, the intensivist takes on the primary role for all patients in the unit. In an open ICU, the primary physician, who may or may not be an intensivist, can differ for each patient. There is increasingly strong evidence that closed units provide better patient outcomes. Patient management in intensive care differs between countries. Open units are the most common structure in the United States, but closed units are often found at large academic centers. Intermediate structures that fall between open and closed units also exist.
Types of intensive care units Intensive care is usually provided in a specialized unit of a hospital called the intensive care unit (ICU) or critical care unit (CCU). Many hospitals also have designated intensive care areas for certain specialities of medicine. The naming is not rigidly standardized, and types of units are dictated by the needs and available resources of each hospital. These include:
coronary intensive care unit (CCU or sometimes CICU) for heart disease medical intensive care unit (MICU) surgical intensive care unit (SICU) pediatric intensive care unit (PICU) pediatric cardiac intensive care unit (PCICU) neuroscience critical care unit (NCCU) overnight intensive-recovery (OIR) shock/trauma intensive-care unit (STICU) neonatal intensive care unit (NICU) ICU in the emergency department (E-ICU)
Medical studies suggest a positive correlation between ICU volume and quality of care for mechanically ventilated patients. After adjustment for severity of illness, demographic variables, and characteristics of the ICUs (including staffing by intensivists), higher ICU volume was significantly associated with lower ICU and hospital mortality rates. For example, adjusted ICU mortality (for a patient at average predicted risk for ICU death) was 21.2% in hospitals with 87 to 150 mechanically ventilated patients annually, and 14.5% in hospitals with 401 to 617 mechanically ventilated patients annually. Hospitals with intermediate numbers of patients had outcomes between these extremes. ICU delirium, formerly and inaccurately referred to as ICU psychosis, is a syndrome common in intensive care and cardiac units where patients who are in unfamiliar, monotonous surroundings develop symptoms of delirium (Maxmen & Ward, 1995). This may include interpreting machine noises as human voices, seeing walls quiver, or hallucinating that someone is tapping them on the shoulder.Nolen-Hoeksema, Susan. "Neurodevelopmental and Neurocognitive Disorders." (Ab)normal Psychology. Sixth ed. New York City: McGraw-Hill Education, 2014. 314. Print. A systematic review found that sleep promotion interventions led to improved outcomes for the overall health of patients in the ICU.
History The English nurse Florence Nightingale pioneered efforts to use a separate hospital area for critically injured patients. During the Crimean War in the 1850s, she introduced the practice of moving the sickest patients to the beds directly opposite the nursing station on each ward so that they could be monitored more closely. In 1923, the American neurosurgeon Walter Dandy created a three-bed unit at the Johns Hopkins Hospital. In these units, specially trained nurses cared for critically ill postoperative neurosurgical patients.
The Danish anaesthesiologist Bjørn Aage Ibsen became involved in the 1952 poliomyelitis epidemic in Copenhagen, where 2722 patients developed the illness in a six-month period, with 316 of those developing some form of respiratory or airway paralysis. Some of these patients had been treated using the few available negative pressure ventilators, but these devices (while helpful) were limited in number and did not protect the patient's lungs from aspiration of secretions. Ibsen changed the management directly by instituting long-term positive pressure ventilation using tracheal intubation, and he enlisted 200 medical students to manually pump oxygen and air into the patients' lungs around the clock. At this time, Carl-Gunnar Engström had developed one of the first artificial positive-pressure volume-controlled ventilators, which eventually replaced the medical students. With the change in care, mortality during the epidemic declined from 90% to around 25%. Patients were managed in three special 35-bed areas, which aided charting medications and other management.
In 1953, Ibsen set up what became the world's first intensive care unit in a converted student nurse classroom in Copenhagen Municipal Hospital. He provided one of the first accounts of the management of tetanus using neuromuscular-blocking drugs and controlled ventilation. The following year, Ibsen was elected head of the department of anaesthesiology at that institution. He jointly authored the first known account of intensive care management principles in the journal Nordisk Medicin, with Tone Dahl Kvittingen from Norway.
For a time in the early 1960s, it was not clear that specialized intensive care units were needed, so intensive care resources were brought to the room of the patient that needed the additional monitoring, care, and resources. It became rapidly evident, however, that a fixed location where intensive care resources and dedicated personnel were available provided better care than ad hoc provision of intensive care services spread throughout a hospital. In 1962, in the University of Pittsburgh, the first critical care residency was established in the United States. In 1970, the Society of Critical Care Medicine was formed.history reference: Brazilian Society of Critical Care SOBRATI Video: ICU History Historical photos
Monitoring Monitoring refers to various tools and technologies used to obtain information about a patient's condition. These can include tests to evaluate blood flow and gas exchange in the body, or to assess the function of organs such as the heart and lungs. Broadly, there are two common types of monitoring in the ICU: noninvasive and invasive.
Noninvasive monitoring Noninvasive monitoring does not require puncturing the skin and usually does not cause pain. These tools are more inexpensive, easier to perform, and faster to result.
Vital signs which include heart rate, blood pressure, breathing rate, body temperature Capnography to confirm correct position of an endotracheal tube and estimate adequacy of ventilation in mechanically ventilated patients Echocardiogram to evaluate the function and structure of the heart Electroencephalography (EEG) to assess electrical activity of the brain Electrocardiogram to monitor the heart's rhythm and detect changes or abnormalities in its electrical activity caused medical problems such as electrolyte disturbances and inadequate coronary blood flow Pulse oximetry for monitoring oxygen levels in the blood Thoracic electric bioimpedance (TEB) cardiography to monitor fluid status and heart function Ultrasound to evaluate internal structures including the heart, lungs, gallbladder, liver, kidneys, bladder, and blood vessels
Invasive monitoring Invasive monitoring generally provides more accurate measurements, but these tests may require blood draws, puncturing the skin, and can be painful or uncomfortable.
Arterial line to directly monitor blood pressure and obtain arterial blood gas measurements Blood draws or venipucture to monitor various blood components as well as administer therapeutic treatments Intracranial pressure monitoring to assess pressures inside the skull and on the brain Intravesicular manometry (bladder pressure) measurements to assess for intra-abdominal pressure Central line and peripherally inserted central catheter (PICC) lines for drug infusions, fluids or total parenteral nutrition Bronchoscopy to look at lungs and airways and sample fluid within the lungs Pulmonary artery catheter to monitor the function of the heart, blood volume, and tissue oxygenation
Procedures and treatments Intensive care usually takes a system-by-system approach to treatment. In alphabetical order, the key systems considered in the intensive care setting are: airway management and anaesthesia, cardiovascular system, central nervous system, endocrine system, gastro-intestinal tract (and nutritional condition), hematology, integumentary system, microbiology (including sepsis status), renal (and metabolic), and respiratory system.
Airway management and anaesthesia Bag valve mask ventilation and laryngoscopy Induction and maintenance of anaesthesia and sedation including rapid sequence induction for endotracheal intubation to facilitate mechanical ventilation.
Cardiovascular Point of care echocardiography Central venous and arterial catherisation Temporary cardiac pacing catheters for atrial, ventricular, or dual-chamber pacing Intra-aortic balloon pumping to stabilize patients with cardiogenic shock Ventricular assist device to aid in the function of the left ventricle, commonly in patients with advanced heart failure Extracorporeal membranous oxygenation
Gastro-intestinal tract Feeding tube for artificial nutrition Nasogastric intubation can be used to deliver artificial nutrition, but can also be used to remove stomach and intestinal contents Peritoneal aspiration and lavage to sample fluid in the abdominal cavity
Renal Hemofiltration for acute kidney injury
Respiratory Mechanical ventilation to assist breathing and oxygenation through an endotracheal tube, tracheotomy (invasive) or mask, helmet (non-invasive). Thoracentesis or tube thoracostomy to remove fluid or air in the pleural cavity Percutaneous dilatational tracheostomy insertion and ongoing management. Bronchoscopy including lavage.
Drugs A wide array of drugs including but not limited to: inotropes such as Norepinephrine, sedatives such as Propofol, analgesics such as Fentanyl, neuromuscular blocking agents such as Rocuronium and Cisatracurium as well as broad spectrum antibiotics.
Physiotherapy and mobilization Interventions such as early mobilization or exercises to improve muscle strength are sometimes suggested.
Common complications in the ICU Intensive care units are associated with increased risk of various complications that may lengthen a patient's hospitalization. Common complications in the ICU include: Acute renal failure Catheter-associated bloodstream infection Catheter-associated urinary tract infection Delirium Gastrointestinal bleeding Pressure ulcer Venous thromboembolism Ventilator-associated pneumonia Ventilator-induced barotrauma Death
Training