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The intensive care unit (ICU) room is a highly specialized environment, differing in many ways from a standard hospital room. ICU rooms are staffed with a higher nursing staffing ratio, typically one nurse to two rooms, and a premium is placed on patient visibility. Units are often constructed in such a manner that all patients can be under continuous observation from the central-nursing station, either directly or using cameras. Patients are individually monitored with a variety of bedside physiologic monitors, and ICU rooms are designed to have redundant gas and electric sources.


Definitions and Terms


  • ▪  Headwall: The wall behind the head of a patient in an ICU, in which electrical, gas, and equipment mounts are deployed—while headwalls are typical, columns and movable, jointed arms are used in some units (ie, pediatric) to permit more flexible bed/crib configurations (Figure 1-1).
  • ▪  Physiologic monitor: A piece of medical equipment that serves as a central aggregation and display location for many medically significant physiologic variables, including electrocardiogram (ECG), various pressure waveforms, noninvasive blood pressure, pulse oximetry, respiration, temperature, and so on (Figure 1-2).
  • ▪  Telemetry: Electronic transmission of medical data to a central analysis station (Figure 1-3).
  • ▪  Electrocardiography: Analysis and display of data regarding cardiac conduction and rhythm (Figure 1-4).
  • ▪  Pulse oximetry: Photoelectric, noninvasive measurement of capillary oxygen levels using light transmission through a capillary bed to a receiver (Figure 1-5).
  • ▪  Impedance pneumography: A technique by which respiratory rate is measured using electrical changes between ECG leads induced by changes in intrathoracic air volume during inspiration and expiration.
  • ▪  Wall oxygen supply: Oxygen is piped into hospitals from a central supply source typically on the hospital grounds—gases are distributed to outlets throughout the hospital which are both color coded and distributed using gas specific connectors to mechanical ventilators and/or gas blenders. While colors for medical gases vary among countries, green (Figure 1-6) is used to indicate oxygen in the United States (whereas white is used in the United Kingdom). Wall oxygen is supplied at 50 pounds per square inch (psi) and distributed throughout the hospital from central liquid oxygen containers.
  • ▪  Wall air supply: Compressed air is piped to ICU headwalls using a separate and distinct piping system and is dispensed at the bedside through a specific color coded and connector specific gas outlet—air is blended with oxygen to dispense specific oxygen concentrations to the patient. In the United States, the color yellow (Figure 1-7) is used to indicate compressed air (whereas black and white are used in the United Kingdom). Wall air is typically supplied at 50 psi.
  • ▪  Wall suction: A separate suction system is available at each ICU bedside and used for a variety of applications (Figure 1-8), including suction on drains (ie, chest tubes, gastric tubes, abdominal drains, etc.) and pulmonary secretion removal. Vacuum pressure ...

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