Intensive care medicine

Mechanical ventilation may be required if a patient's unassisted breathing is insufficient to oxygenate the blood.

Intensive Care Medicine or critical care medicine is a branch of medicine concerned with the provision of life support or organ support systems in patients who are critically ill and who usually require intensive monitoring.

Patients requiring intensive care usually require support for hemodynamic instability (hypertension/hypotension), airway or respiratory compromise (such as ventilator support), acute renal failure, potentially lethal cardiac dysrhythmias, and frequently the cumulative effects of multiple organ system failure. Patients admitted to the intensive care unit not requiring support for the above are usually admitted for intensive/invasive monitoring, such as the crucial hours after major surgery when deemed too unstable to transfer to a less intensively monitored unit.

Ideally, intensive care is usually only offered to those whose condition is potentially reversible and who have a good chance of surviving with intensive care support. Since the critically ill are so close to dying, the outcome of this intervention is difficult to predict. Many patients, therefore, die in the Intensive Care Unit. A prime requisite for admission to an Intensive Care Unit is that the underlying condition can be overcome. Therefore, treatment is merely meant to win time in which the acute affliction can be resolved.

Medical studies suggest a relation between intensive care unit (ICU) volume and quality of care for mechanically ventilated patients.^[1] 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.

It is generally the most expensive, technologically advanced and resource intensive area of medical care. In the United States estimates of the 2000 expenditure for critical care medicine ranged from US$15-55 billion accounting for about 0.5% of GDP and about 13% of national health care expenditure (Halpern, 2004).

Organ systems

Intensive care usually takes a system by system approach to treatment, rather than the SOAP (subjective, objective, analysis, plan) approach of high dependency care. The nine key systems (see below) are each considered on an observation-intervention-impression basis to produce a daily plan. As well as the key systems, intensive care treatment also raises other issues including psychological health, pressure points, mobilisation and physiotherapy, and secondary infections.

The nine key IC systems are (alphabetically): cardiovascular system, central nervous system, endocrine system, gastro-intestinal tract (and nutritional condition), hematology, microbiology (including sepsis status), peripheries (and skin), renal (and metabolic), respiratory system.

The provision of intensive care is generally administered 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, such as the Coronary Care Unit (CCU) for heart disease, Medical Intensive Care Unit (MICU), Surgical Intensive Care Unit (SICU), Pediatric Intensive Care Unit (PICU), Neuroscience Critical Care Unit (NCCU), Overnight Intensive Recovery (OIR), Shock/Trauma Intensive Care Unit (STICU), Neonatal Intensive Care Unit (NICU), and other units as dictated by the needs and available resources of each hospital. The naming is not rigidly standardized. For a time in the early 1960s, it was not clear that specialized intensive care units were needed, so intensive care resources (see below) were brought to the room of the patient who needed the additional monitoring, care, and resources. It became rapidly evident, though, that a fixed location where intensive care resources and personnel were available provided better care than ad hoc provision of intensive care services spread throughout a hospital.

Equipment and systems

An endotracheal tube

Common equipment in an intensive care unit (ICU) includes mechanical ventilation to assist breathing through an endotracheal tube or a tracheotomy; hemofiltration equipment for acute renal failure; monitoring equipment; intravenous lines for drug infusions fluids or total parenteral nutrition, nasogastric tubes, suction pumps, drains and catheters; and a wide array of drugs including inotropes, sedatives, broad spectrum antibiotics and analgesics.

Physicians, veterinary criticalists and intensivists

Critical care medicine is a relatively new but increasingly important medical specialty. Physicians who have training in critical care medicine are referred to as intensivists. The specialty requires additional fellowship training for physicians who complete their primary residency training in internal medicine, anesthesiology, or surgery. Board certification in critical care medicine is available through all three specialty boards. Intensivists with a primary training in internal medicine sometimes pursue combined fellowship training in another subspecialty such as pulmonary medicine, cardiology, infectious disease, or nephrology. The Society of Critical Care Medicine is a well established multiprofessional society for practitioners who work in the ICU, including intensivists. Medical research has repeatedly demonstrated that ICU care provided by intensivists produces better outcomes and more cost effective care. This has led the Leapfrog Group to make a primary recommendation that all ICU patients be managed or co-managed by a dedicated intensivist who is exclusively responsible for patients in one ICU. Unfortunately there is a critical shortage of intensivists in the United States and most hospitals lack this critical physician team member.

In veterinary medicine, critical care medicine is recognized as a specialty and is closely allied with emergency medicine. Board-certified veterinary critical care specialists are known as criticalists, and generally are employed in referral institutions or universities.

Patient management in intensive care differs significantly between countries. In Australia, where Intensive Care Medicine is a well established speciality, ICUs are described as 'closed'. In a closed unit the intensive care specialist takes on the senior role where the patient's primary doctor now acts as a consultant. Other countries have open Intensive Care Units, where the primary doctor chooses to admit and generally makes the management decisions. There is increasingly strong evidence that 'closed' Intensive Care Units staffed by Intensivists provide better outcomes for patients.^[2][3]

History

Florence Nightingale era

Florence Nightingale

The ICU's roots can be traced back to the Monitoring Unit of critical patients through nurse Florence Nightingale. The Crimean War began in 1854 when Britain, France and Turkey declared war on Russia. Because of the lack of critical care and the high rate of infection, there was a high mortality rate of hospitalised soldiers, reaching as high as 40% of the deaths recorded during the war. Nightingale and 38 other volunteers had to leave for the Fields of Scurati, and took their "critical care protocol" with them. Upon arriving, and practicing, the mortality rate fell to 2%. Nightingale contracted typhoid, and returned in 1856 from the war. A school of nursing dedicated to her was formed in 1859 in England. The school was recognised for its professional value and technical calibre, receiving prizes throughout the British government. The school of nursing was established in Saint Thomas Hospital, as a one year course, and was given to doctors. It used theoretical and practical lessons, as opposed to purely academic lessons. Nightingale's work, and the school, paved the way for intensive care medicine.

Dandy era

Walter Edward Dandy was born in Sedalia, Missouri. He received his BA in 1907 through the University of Missouri and his M.D. in 1910 through the Johns Hopkins University School of Medicine. Dandy worked one year with Dr. Harvey Cushing in the Hunterian Laboratory of Johns Hopkins before entering its boarding school and residence in the Johns Hopkins Hospital. He worked in the Johns Hopkins College in 1914 and remained there until his death in 1946. One of the most important contributions he made for neurosurgery was the air method in ventriculography, in which the cerebrospinal fluid is substituted with air to help an image form on an X-Ray of the ventricular space in the brain. This technique was extremely successful for identifying brain injuries. Dr. Dandy was also a pioneer in the advances in operations for illnesses of the brain affecting the glossopharyngeal as well as Meniere's syndrome, and he published studies that show that high activity can cause sciatic pain. Dandy created the first ICU in the world, 03 beds, Boston,1926.

Ibsen era

Bjorn Aage Ibsen (1915-2007) graduated in 1940 from medical school at the University of Copenhagen and trained in anesthesiology from 1949 to 1950 at the Massachusetts General Hospital, Boston. He became involved in the 1952 poliomyelitis outbreak in Denmark, where 2722 patients developed the illness in a 6 month period, with 316 suffering respiratory or airway paralysis. Treatment had involved the use of the few negative pressure respirators available, but these devices, while helpful, were limited and did not protect against aspiration of secretions. Ibsen changed management directly, instituting protracted positive pressure ventilation by means of intubation into the trachea, and enlisting 200 medical students to manually pump oxygen and air into the patients lungs. At this time Carl-Gunnar Engström had developed one of the first positive pressure volume controlled ventilators, which eventually replaced the medical students. In this fashion, mortality declined from 90% to around 25%. Patients were managed in 3 special 35 bed areas which aided charting and other management. In 1953 Ibsen set up what became the world's first Medical/Surgical ICU in a converted student nurse classroom in Kommunehospitalet (The Municipal Hospital) in Copenhagen, and provided one of the first accounts of the management of tetanus with muscle relaxants and controlled ventilation. In 1954 Ibsen was elected Head of the Department of Anaesthesiology at that institution. He jointly authored the first known account of ICU management principles in Nordisk Medicin, September 18, 1958: ‘Arbejdet på en Anæsthesiologisk Observationsafdeling’ (‘The Work in an Anaesthesiologic Observation Unit’) with Tone Dahl Kvittingen from Norway. He died in 2007.

Safar era

Peter Safar, the first Intensivist doctor in the USA, was born in Austria as the son of two doctors. He first migrated to the United States in 1949. Safar first got certification as an anesthetist, and in the 1950s he started and praised the "Urgency & Emergency" room setup (now known as an ICU). It was at this time the ABCs (Airway, Breathing, and Circulation) protocols were formed, and artificial ventilation as well as external cardiac massage became popular. These experiments counted on volunteers of its team which only used minimum sedation. It was through these experiments that the techniques for maintaining life in the critical patient were established.

The first surgical ICU was established in Baltimore, and, in 1962, in the University of Pittsburgh, the first Critical Care Residency was established in the United States. It was around this time that the induction of hypothermia in critical patients was also tested.

In 1970 the SCCM was formed. (Society of Critical Care Medicine). history reference: Brazilian Society of Critical Care SOBRATI Video:ICU History Historical photos

References

• Intensive Care Medicine by Irwin and Rippe
• The ICU Book by Marino
• Procedures and Techniques in Intensive Care Medicine by Irwin and Rippe
• Halpern NA, Pastores SM, Greenstein RJ. Critical care medicine in the United States 1985-2000: an analysis of bed numbers, use, and costs. Crit Care Med 2004;32:1254-9. PMID 15187502.
• History Reference:
• Brazilian Society of Intensive Care - SOBRATI
• History
• Society of Critical Care Medicine

See also

• Neonatal Intensive Care Unit
• Intensive Care Unit
• Internet Rounds

External links

• Society of Critical Care Medicine
• Veterinary Emergency And Critical Care Society
• ESICM : European Society of Intensive Care Medicine

Notes

1. ↑ Kahn JM, Goss CH, Heagerty PJ, Kramer AA, O'Brien CR, Rubenfeld GD. (2006). "Hospital volume and the outcomes of mechanical ventilation". New England Journal of Medicine 355 (1): 41–50. doi:10.1056/NEJMsa053993. PMID 16822995. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=16822995&dopt=Abstract. Retrieved on 2006-08-02. 
2. ↑ Manthous CA, Amoateng-Adjepong Y, al-Kharrat T, Jacob B, Alnuaimat HM, Chatila W, Hall JB. (1997). "Effects of a medical intensivist on patient care in a community teaching hospital" (Abstract). Mayo Clinic Proceedings 72 (5): 391–9. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=9146680&dopt=Abstract. Retrieved on 2006-09-02. 
3. ↑ Hanson CW 3rd, Deutschman CS, Anderson HL 3rd, Reilly PM, Behringer EC, Schwab CW, Price J. (1999). "Effects of an organized critical care service on outcomes and resource utilization: a cohort study" (Abstract). Critical Care Medicine 27 (2): 270–4. doi:10.1097/00003246-199902000-00030. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=retrieve&db=pubmed&list_uids=10075049&dopt=Abstract. Retrieved on 2006-09-02.