You are visiting a website that is not intended for your region

The page or information you have requested is intended for an audience outside the United States. By continuing to browse you confirm that you are a non-US resident requesting access to this page or information.

Switch to the US site

Select Your Country or Region
Continue
Contact
Getinge Flow-i

Low-flow anesthesia

Topics

Why low-flow anesthesia?

Already in 1924 RM Waters published an article in Anesthesia and Analgesia where he presents improved economy, convenience and welfare of the patients as the benefits of using a re-breathing system during anesthesia [1]. This is still true today but we can also add welfare of the planet as another major benefit.

Low-flow anesthesia offers pulmonary, economic and environmental benefits

In low-flow anesthesia, a rebreathing system uses a fresh gas flow (FGF) that is less than the alveolar ventilation of the patient. This technique uses less anesthetic agents than conventional systems, emits less gas into the atmosphere, and improves the flow dynamics of the inhaled air. Low flow is generally characterized by a fresh gas flow of less than 1.0 L/min. In minimal flow, the FGF is decreased to 0.5 L/min.

Should we change to low- or minimal-flow anesthesia?

Reducing the fresh gas flow has several benefits:

web-anesthesia-low-flow-icon-economy

Economy

Agent expenditure accounts for a large part of the total cost of ownership of anesthesia machines. Reducing the anesthetic agent consumption in your ORs will have a positive impact on your overall hospital expenditure.

web-anesthesia-low-flow-environmental

Environmental impact

With low-flow anesthesia, a lower amount of anesthetic agent is released into the environment, reducing the impact of fluorocarbons and nitrous oxide on the ozone layer, thus reducing the overall greenhouse gas emissions.

web-anesthesia-low-flow-patient-safety

Patient comfort and safety

Low FGF improves the flow dynamics of inhaled gases, increases mucociliary clearance, maintains body temperature and reduces water loss. 

web-anesthesia-low-flow-staff-safety

OR staff safety

With less unused surplus gas discharged into the atmosphere, the concentration of anesthesia gas in the OR is greatly reduced. This minimizes occupational risk for OR staff.

Theory and practice of minimal fresh gas flow anesthesia

The review by Brattwall et al. in the Canadian Journal of Anesthesia, outlines the benefits of minimal fresh gas flow anesthesia.  It provides practical guidance on safe implementation of low- and minimal-flow anesthesia in routine clinical practice.

 

What are potential risks of low-flow anesthesia?

Hypoxic mixtures

The formation of hypoxic mixtures are one of the greatest risk of using low-flow anesthesia. Reducing fresh gas flow in a rebreathing circle system results in a difference between the delivered O2 concentration(FD) at the common gas outlet and the inspired O2 (FIO2). Consequently, FIO2 becomes lower than the fraction of delivered oxygen (FDO2). This may not always be sufficiently recognized, and if settings are not adjusted, hypoxic mixtures can develop. An active inspired hypoxic guard has been shown to prevent the formation of hypoxic mixtures. 

 
 
Inadequate depth of anesthesia

During low-flow anesthesia there is a potential risk for inadequate anesthetic gas concentration. An automatic gas control (AGC) system removes the need for continuous manual adjustments of FGF, FIO2 and EtAA. Targeting FIO2 directly will help avoid hypoxia. Targeting EtAA at the desired speed will reduce the risk of under- or overdosing.

Learn more about our Automatic Gas Control (AGC) 

Related articles

PowerLED II
  • Operating Room

Reducing visual fatigue in the OR

Reducing contrast between the surgical site and surrounding areas improve comfort and visual performance. The most effective surgical lighting will provide a gradual transition between the illuminated area and the operating room lighting to reduce eyestrain.

Read more

Ventilation performance
  • Operating Room

Ventilation performance

If all perioperative organ injuries were grouped, they would be the third leading cause of death in the USA. Prevention of organ injury, such as lung damage, could reduce the need for postoperative escalation of care. Learn more about how lung protective ventilation can participate to reduce health-related complications and costs.

Read more

  • Operating Room

Keeping patients’ lungs healthy

Restoring and preserving your patients’ health are the main goals of healthcare. This includes trying to avoid potential postoperative complications related to anesthesia, such as atelectasis.

Read more

Heart-lung interactions
  • Operating Room

Heart lung interaction

Anesthesia-induced lung collapse is a well-known entity which can be avoided by a good ventilatory strategy.

Read more

Optimizing Patient Positioning in the OR
  • Operating Room

Patient Positioning in the OR

Proper patient positioning is an important prerequisite for a successful surgical procedure. Optimum positioning not only ensures the best possible access to the surgical site, but prevents the long-term consequences of nerve damage or pressure ulcers.

Read more

Maquet PowerLED II
  • Operating Room

Brighter lighting isn't necessarily better

Most people have experienced the symptoms of visual fatigue: eyes that feel sore, itchy, or dry. Sometimes our bodies compensate by producing excess tears, causing visual impairment.

Read more

All references

  1. Waters R.M 1924 Clinical scope and utility of carbon dioxid filtration in inhalation anesthesia. Anesthesia and Analgesia Feb p 20-22, 26

Subscription