CHAPTER 25

Anesthesia Machine Checkout

Ramon Larios and Esther Sung

Introduction

The delivery of a safe anesthetic in modern-day practice begins with a checkout of the anesthesia machine. Improper or lack of inspection of anesthetic equipment prior to use has been associated with several significant incidents. Failure to check equipment clearly results in an increased risk of operative morbidity and mortality. With the large variety of anesthetic delivery systems available today, it is critical to understand the basic components of the system so that malfunctions can be detected prior to use or when failure occurs during use. Moreover, regular testing may lead to improved preventive maintenance and enhanced familiarity with the equipment. This chapter focuses on the fundamental components of the anesthesia machine checkout. Specific issues related to unique anesthesia delivery systems should be resolved by referring to the appropriate manufacturers’ operator manuals.

History of Machine Checkout Recommendations

In 1993, a joint effort between the American Society of Anesthesiologists (ASA) and the U.S. Food and Drug Administration (FDA) resulted in the 1993 FDA Anesthesia Apparatus Checkout Recommendations. This simplified the initial 1986 preuse checkout and made it more user-friendly. At the time, the 1993 checklist focused on components that were immediately dangerous for patients and mechanisms that failed more regularly. This checklist was applicable to most commonly available anesthesia machines. Nevertheless, despite the recognized importance of an anesthesia machine checkout, available evidence suggests that the 1993 recommendations were neither well understood nor reliably used by anesthesia providers.

Moreover, because of recent and ongoing fundamental changes to the various anesthesia machine designs, the 1993 FDA preuse checklist may no longer be universally applicable to all anesthesia delivery systems. As more machines incorporate electronic checkouts, the user must determine which portions are automatically checked and which portions require manual checks. In such cases, the anesthesia care provider must be aware that the electronic machine check may not be a comprehensive preanesthesia checkout. The user should follow the equipment manufacturer’s recommended preuse checklist, utilizing both its automated and manual components: for example, the machine may check the high and low-pressure systems for leaks and the electronics of the ventilator, but the user may still need to perform manual checks of the pressure release of the breathing circuit, of auxiliary oxygen, and of backup emergency ventilation.

As a result, in 2005, the ASA’s Committee on Equipment and Facilities, in conjunction with the American Association of Nurse Anesthetists (AANA) and the American Society of Anesthesia Technologists and Technicians (ASATT), began to develop a revised preuse checklist that was designed to be more workstation specific. These recommendations were published in 2008 and were intended to eventually replace the 1993 FDA Anesthesia Apparatus Checkout Recommendations. Rather than a checklist with specific instructions on how to perform each test, these new guidelines elaborate on specific systems and subsystems that must be evaluated. It is ultimately up to the user, along with the anesthesia machine manufacturer, to determine the actual mechanisms and/or specific checks that should be used to accomplish these subsystem evaluations. Appropriate personalized checkout procedures may need to be developed for individual machines and practices.

The 1993 Anesthesia Apparatus Checkout Recommendations placed all of the responsibility for the preuse checkout on the anesthesia provider. The new 2008 recommendations identify certain aspects of the preanesthesia checkout that may be performed by a qualified anesthesia technician or a biomedical technician (http://www.apsf.org/newsletters/html/2008/spring/05_new_guidelines.htm).

Redundancy in the critical aspects of the checkout process makes it more likely that problems will be identified prior to use for a patient. Nevertheless, regardless of the additional support of technicians, the anesthesia care provider is ultimately responsible for the proper function of all equipment used to deliver anesthesia care.

The anesthesia machine, in addition to the maintenance schedule imposed by the manufacturer, undergoes a detailed checkout of all its functions at the beginning of every day. In addition, prior to every case, the provider performs a shorter checkout of the machine’s most essential functions and those most likely to have developed a temporary interruption between cases (breathing circuit integrity; adequate suction; adequate anesthesia gas in vaporizer, gas flows, and working monitors) but does not repeat in detail all the gas pipeline and electrical power checks performed in the morning unless the machine has been moved or there is some other reason to think they may have been altered.

Anesthesia Machine Checkout Procedure

As stated earlier, the goal of the preanesthesia checkout is to allow for the safe delivery of anesthesia care. Requirements for safe delivery of anesthetic care include the following:

The new guidelines for the preanesthesia checkout procedures consist of 15 items. These items must be performed as part of a complete preanesthesia checkout on a daily basis (items that must be completed prior to each procedure are in bold). The 15 items are as follows:

1. Verify that auxiliary oxygen cylinder and self-inflating manual ventilation device are available and functioning.
Anesthesia ventilator failure resulting in the inability to provide patient ventilation is rare but can occur at anytime. For those situations where the problem cannot be immediately identified or corrected, a manual ventilation device (e.g., bag valve mask) may be necessary to provide positive pressure ventilation until the problem is resolved. As a result, a self-inflating manual ventilation device and an auxiliary oxygen cylinder should be available and checked for proper function at each anesthesia setting.
In addition, the oxygen cylinder should have a regulator, and a device to open the cylinder valve should be present. A full E cylinder of oxygen has a pressure of about 2,000-pound-force per square inch gauge (psig), which is equivalent to around 625 L of oxygen. After checking the oxygen cylinder pressure to ensure adequate supply, the cylinder should be stored with the valve closed in order to prevent unintended leakage or drainage of oxygen.

2. Verify that patient suction is adequate to clear the airway.
The immediate ability to clear airway secretions or gastric contents is essential for safe anesthetic care. Inability to visualize the glottic opening and therefore delay in timely acquisition of a secure airway can be dangerous and possibly fatal. Aspiration of gastric contents can cause prolonged intubation and airway complications. Adequate strength of the suction can be tested by occluding the suction tubing orifice with the underside of a thumb and determining if the weight of the suction tubing can be supported at waist height. Prior to anesthesia, adequate suction should be checked, and a rigid suction catheter (e.g., Yankauer) should be available on the machine.

3. Turn on the anesthesia delivery system and confirm that AC power is available.
AC power and the availability of backup battery power should be confirmed prior to the delivery of anesthesia. Visual indicators of the power systems exist on most anesthesia delivery systems. These should be confirmed as should appropriate connection of the power cord to a working AC power source. If the AC power is not confirmed, complete system shutdown is at risk when battery power is unknowingly depleted. Desflurane vaporizers, if used, should be checked for adequate electrical power source as well.

4. Verify availability of required monitors and check alarms.
The patient’s oxygenation, ventilation, circulation, and temperature should be continually evaluated according to the ASA’s Standards for Basic Anesthetic Monitoring. Verification of the availability and proper function of the appropriate monitoring supplies should be performed prior to each anesthetic. Examples of necessary equipment include, but are not limited to, blood pressure cuffs, pulse oximetry probes, electrocardiogram (ECG) leads, and capnography. Moreover, the appropriate audible or visual alarms that would indicate problems with, or disruption of, patient oxygenation, ventilation, circulation, and temperature should be intact. It is prudent for the anesthesiology technician to turn off the monitors and then turn them back on between cases to be sure that alarms are reset to default values as designed by each individual institution.

5. Verify that pressure is adequate on the spare oxygen cylinder mounted on the anesthesia machine.
Spare oxygen cylinders are mounted on anesthesia machines in the event that central oxygen supply is lost. Anesthesia machines require oxygen not only to provide oxygen to the patient but often to power pneumatically driven ventilators. The pressure of the oxygen cylinders should be checked to ensure an acceptable amount of backup oxygen is available. The oxygen cylinder valves should be closed after verification in order to prevent unrecognized depletion of the cylinder due to pressure fluctuations in the machine during mechanical ventilation or in the event of actual pipeline supply failure.
Rarely, the cylinder is intended to be the primary oxygen source. In these cases, if the ventilator is pneumatically driven, then the oxygen cylinder supply may be depleted quickly. As a result, manual or spontaneous ventilation may be more appropriate in order to maximize the duration of oxygen supply. On the other hand, the duration of oxygen supply for electrically powered or piston-driven ventilators depends only on total fresh oxygen gas flow.

6. Verify that the piped gas pressures are ≥50 psig. Since there are many scenarios that may cause disruption of gas delivery from a central source, pressure in the piped gas supply should be checked at minimum once per day in order to ensure that adequate pressure is available for proper function of the anesthesia machine. If the pipeline hoses have been disconnected in order to move the anesthesia machine at any point during the day, the hoses should be reconnected to the central pipeline supply, and the fittings should be examined for firm connections without audible leaks. The pipeline pressure should be 50-55 psig.

7. Verify that vaporizers are adequately filled and, if applicable, that the filler ports are tightly closed. (Provider completes prior to each procedure; technician can complete daily.)
Adequate supply of volatile anesthetics is requisite for vapor-based anesthetics in order to reduce the likelihood of inadequate anesthesia and recall under anesthesia. In addition, many vaporizers do not have low-agent alarms, so checking prior to usage is important. After filling the vaporizers, filler ports should be adequately tightened to prevent unrecognized leakage, especially for older vaporizers that do not have systems that automatically close after completion of refilling. Vaporizers should also be secured so that they cannot tilt or be lifted from their mounts.

8. Verify that there are no leaks in the gas supply lines between the flowmeters and the common gas outlet. (If the vaporizer has been changed, this should be rechecked prior to use.)
   The low-pressure component of the anesthesia machine circuit is located between the flow control valves and the common gas outlet. The leak test checks the integrity of the anesthesia machine in this part of the circuit. The components located within this area are subject to breaking and developing leaks. Leaks in the low-pressure circuit can cause leakage of oxygen from the inspired gas and delivery of a hypoxic gas mixture. Likewise, leakage of inhaled anesthetic can result in the patient receiving much less gas anesthetic than is indicated on the machine vaporizer, which places the patient at risk for awareness under anesthesia. In addition, each individual vaporizer must be turned on in order to check for leaks within each vaporizer or at the mount, and it is especially important to recheck this test whenever a vaporizer is changed.
   Several different methods have been used to check the low-pressure circuit for leaks. One reason for the large number of methods is that the internal design of various machines differs considerably. The clearest example is the difference between most GE Healthcare/Datex-Ohmeda and Dräger Medical workstations. Most GE Healthcare/Datex-Ohmeda workstations have a check valve near the common gas outlet, whereas Dräger Medical workstations do not. The presence or absence of this check valve may determine which preoperative leak test is indicated. The check valve is located downstream from the vaporizers and upstream from the oxygen flush valve, and it is open in the absence of back pressure. Gas flow from the manifold moves a rubber flapper valve off its seat, thereby allowing the gas to proceed freely to the common outlet. The valve closes when back pressure is exerted on it, preventing the flow of gas back into the machine and through a leak. Examples of back pressure that can cause the check valve to close are oxygen flushing, peak breathing circuit pressures generated during positive pressure ventilation, and the use of a positive pressure leak test.
   Typically, the low-pressure circuit of anesthesia workstations without an outlet check valve can be tested with a positive pressure leak test (e.g., with Dräger Medical machine). When performing a positive pressure leak test, the operator generates positive pressure in the low-pressure circuit by using flow from the anesthesia machine or from a positive pressure bulb to detect a leak. One common test is the retrograde fill test, which is performed by closing the adjustable pressure-limiting (APL) valve and occluding the patient port. Oxygen flow or flush is used to fill and distend the reservoir bag, and flow is adjusted so that a pressure of 30 cm H2O on the manometer is maintained in the breathing system. No more than 350 mL/min flow should be necessary to maintain a steady pressure. When complete, the pressure should be relieved by opening the APL valve, not by opening the patient port. Relieving the pressure by opening the patient port could cause CO2 absorbent dust to enter the system. Notably, the retrograde fill test checks both the low-pressure part of the machine and the breathing circuit and does not isolate the source of the leak. In addition, it is not very sensitive to small leaks.
   Machines with check valves must be tested with a negative pressure leak test (e.g., GE Healthcare/Datex-Ohmeda machine). When performing a negative pressure leak test, the operator creates negative pressure in the low-pressure circuit by using a suction bulb to detect leaks. In order to do this, the machine’s master switch, flow control valves, and vaporizers should all be initially turned off. The suction bulb is attached by tubing and an adapter to the common fresh gas outlet, and the bulb is squeezed repeatedly until it is fully collapsed. This creates a vacuum in the low-pressure system. If the bulb stays collapsed for at least 10 seconds, the system is free of leaks, but if the bulb reinflates during this period, a leak is present. The test is repeated with each vaporizer individually turned to the “on” position because leaks inside the vaporizer can be detected only when the vaporizer is turned on. The negative pressure leak test is the most sensitive leak test, as it can detect leaks as small as 30 mL/min. This test is used to be considered the universal leak test since it works for machines with or without a check valve, but unfortunately, many new machines do not have accessible common gas outlets. Most machines whose low-pressure system cannot be tested via the common gas outlet are tested for low-pressure leaks electronically.
   For specific instructions, the appropriate anesthesia machine manual should be referenced, as there are many machines that have automated checks and/or variations to these procedures.

9. Test scavenging system function.
To prevent room contamination by anesthetic gases, a functional scavenging system is necessary. The connections between the anesthetic machine and the scavenging system must be checked daily to ensure integrity of the scavenging system. The anesthesia technician should be particularly careful to remember to attach the scavenging system to the evacuation system when moving anesthesia machines to out-of-operating room (OR) locations of care. There are various scavenging system designs that may require that an adequate vacuum level be present. On active systems (e.g., full vacuum), vacuum pressure can be modulated by the screw valve. Most modern scavenging systems have positive and negative pressure relief valves. The positive pressure relief valve allows exhaled gases to be released into the OR in the event of inadequate vacuum (usually occurs in an active system when someone inadvertently closes the screw valve). The negative pressure relief valve prevents suction in an active vacuum system from affecting airway pressure in the breathing circuit for the patients. As these valves are important to protect the patient from pressure fluctuations coming from the scavenging system, they must be checked daily. The checks on these valves can be quite complex; therefore, the anesthesia technician should receive specific troubleshooting training from the hospital biomedical engineers and refer more complicated problems to them directly.

10. Calibrate or verify calibration of the oxygen monitor and check the low-oxygen alarm.
Calibration of the oxygen sensor is critical for safe patient care. Continuous monitoring of the inspired oxygen concentration helps prevent the delivery of a hypoxic gas concentration to patients. The oxygen monitor is crucial to detect any changes in the oxygen supply.
   Oxygen sensor calibration should occur at least once per day. Some anesthesia machines are self-calibrating. For these machines, they should be verified to read 21% when sampling room air. The oxygen sensor calibration can be performed by an anesthesia provider or anesthesia technician. If more than one oxygen monitor is present, the primary sensor that will be relied upon for oxygen monitoring during patient care should be the one checked.
   The low–oxygen concentration alarm should also be checked at this time. This is done by setting the low-oxygen alarm above the measured oxygen concentration and confirming that an audible alarm is generated. Detailed oxygen sensor calibration instructions can be found in the specific anesthesia machine’s operator manual.

11. Verify that carbon dioxide absorbent is not exhausted.
A circle breathing system relies on the removal of carbon dioxide to prevent rebreathing of carbon dioxide by the patient (see Chapter 27, The Breathing Circuit). There is a characteristic color change in the carbon dioxide absorbent, depending on the particular absorbent being used, that indicates depletion of the absorbent. When this color change occurs, it is a visual reminder that the absorbent must be replaced. Some newer absorbents change color when they become desiccated. If the carbon dioxide absorbent is exhausted or desiccated, it should be changed.
   It is possible that the carbon dioxide absorbent loses its ability to remove carbon dioxide without producing a color change. For example, an exhausted desiccated absorbent may return to its original color after a period of rest. Capnography, which must be used in every anesthetic, is helpful in indicating the need to replace the absorbent. When the inspired carbon dioxide concentration is detected to be greater than 0, this indicates that the patient is rebreathing carbon dioxide and that the absorbent may be used up and, therefore, needs to be replaced. When replacing carbon dioxide absorbent canisters, it is important to install them correctly. Incorrectly installed carbon dioxide absorbent canisters are a common source of leaks within the anesthesia machine.

12. Breathing system pressure and leak testing. The breathing system leak test must be performed on the components that will be used during a particular anesthetic. If any portion of the circuit is changed after completing the leak test, the leak test must be performed again to ensure the integrity of the breathing system. The purpose of this test is to ensure that adequate pressure can be generated and maintained in the breathing system during assisted ventilation. Adequate pressure is usually considered to be greater than or equal to 30 cm H2O. This test also checks the ability to relieve pressure in the breathing circuit with the APL valve during manual ventilation.
   To manually check the breathing system for leaks, the APL valve is closed and the patient port is occluded at the Y-piece. The oxygen flush valve is used to instill 30-cm H2O pressure into the breathing circuit. If the circle system is free of leaks, the value on the pressure gauge should not decrease. Of note, newer machines may have automated testing that can be used to detect leaks. Additionally, they can also determine the compliance of the breathing system. Once adequate pressure is obtained in the circle system, it can be released by completely opening the APL valve. This step can test for proper functioning of the APL valve, ensuring that it entirely relieves the pressure in the circle system.

13. Verify that gas flows properly through the breathing circuit during both inspiration and exhalation.
Although checking the breathing system for pressure and leaks is important, this test does not assess the function of the unidirectional inspiratory and expiratory valves. The presence of the valves can be assessed visually. To test for proper function of the unidirectional inspiratory and expiratory valves, first remove the Y-piece from the circle system. Next, breathe through the two corrugated hoses separately. The valves should be present, and they should move appropriately. The person performing the test should be able to inhale but not exhale through the inspiratory limb and able to exhale but not inhale through the expiratory limb. At the completion of this test, the breathing circuit should be changed to a fresh circuit prior to attaching the anesthesia machine to the patient. This flow test can also be performed by attaching a breathing bag to the Y-piece and using the ventilator. In addition, capnography can also be useful to detect an incompetent valve. For example, an incompetent inspiratory valve should be considered in situations of high (>0) inspired carbon dioxide concentration.

14. Document completion of the checkout procedures.
A printed copy of the preanesthesia checkout procedures should be retained near or in the anesthesia machine since an organized and systematic list may result in improved fault detection over memory alone. Moreover, a pictorial checklist may be helpful as it can be simpler to follow than a typewritten list. Documentation of checkout procedure completion should be performed and may be important in the case of an adverse incident, as omission of the checkout can by cited as evidence of substandard care. Dates and times of certain checkout procedures may be recorded automatically by some computerized checkout systems, but those that are not automatically recorded should be manually documented by the individual who performs the checkout procedure.
   Record keeping is important to provide supporting evidence that the equipment is being appropriately maintained. Should service be necessary, this record may also be helpful for service representatives who come to repair the equipment, for providing a reminder to check on the repair that was done, and for referencing at a later date what was repaired and who performed the repair. A log of malfunctions may also help to determine if a particular piece of equipment warrants replacement. This record should be retained, should an adverse outcome lead to litigation.

15. Confirm ventilator settings and evaluate readiness to deliver anesthesia care. (Anesthesia provider should perform this.)
Prior to starting each anesthetic, the completion of the preanesthesia checkout procedures should be verified as well as the availability of essential equipment. Ventilator settings should be confirmed and pressure limit settings used as a secondary backup to prevent barotrauma once positive pressure ventilation is used. Specifically, the presence and functionality of appropriate monitors, the capnogram, and oxygen saturation by pulse oximetry should be checked. Proper flowmeter and ventilator settings, placement of the ventilator switch to manual, and adequate filling of the vaporizers should also be ensured before initiation of an anesthetic.
   The delivery of safe anesthetic care in modern practice begins with a thorough evaluation of the anesthetic delivery system being used. Anesthesia providers, along with trained anesthesia technicians and biomedical technicians, must have a thorough understanding of the fundamental components of the anesthesia machine. Thus, malfunctioning components can be repaired or replaced to decrease the potential for patient injury. These preanesthesia machine checks should be documented not only for maintenance records but also for medical-legal reasons. With the great variation in anesthesia machine design, it is important to always refer to the specific anesthesia machine manufacturer’s instruction manual for more detailed information and instruction.

Automated Checkouts

With increasing automaticity in the current environment, anesthesia providers and technologists must not become complacent with automated checks built into modern anesthesia machines. Depending on the machine, it may not be an adequately comprehensive checkout. As machines transition to more automated checkouts, the operator is removed one step further from the actual machine check process, which may reduce familiarity with how the machine actually works. It has been shown in simulation with conventional anesthesia machines that known equipment failures may not be properly diagnosed and managed even by experienced anesthesia providers, as failures become less common and, paradoxically, providers become less adept at rapidly identifying them. This is where a well-trained anesthesia technologist, familiar with the essential engineering functions of the machine, becomes especially vital.

After an anesthesia machine check has passed inspection, malfunctions and failures may still occur. Over the years, there have been multiple reports of automated checks passing inspection, only to discover a malfunction after the start of an anesthetic. Anesthesia equipment may malfunction while providing an anesthetic if a mechanical (or an electronic or software) failure. Anesthesia equipment is frequently moved during a surgical procedure, and this may cause an inadvertent disconnection in tubing or wires on the anesthesia machine. Anesthesia providers and technologists must be ready to act quickly to troubleshoot the problem.

Anesthesia technologists are a critical part of the anesthesia team. Their expertise with the anesthesia machine is invaluable. Even well-trained and prepared anesthesia providers require assistance in checking the anesthesia machine for malfunctions and for troubleshooting them when problems actually occur (see Chapter 29, Preventing and Solving Anesthesia Machine Problems).

Summary

The anesthesia machine is a critical component of safety in the OR. Failures of the anesthesia machine function have the potential to cause significant patient injuries if undetected or if backup fail-safes are not properly deployed. Proper maintenance and a thorough checkout procedure can identify many machine problems before they have a chance to cause patient problems. Multiple organizations and the anesthesia machine manufacturers have been instrumental in devising detailed anesthesia machine checkout procedures. Each machine will have a unique checkout procedure detailed by the manufacturer; all checkout procedures, however, share common concerns. This chapter presents an overview of the machine checkout procedure that should be customized for each anesthesia machine according to the manufacturer.

Review Questions

1.  Which organization(s) was involved in developing the 1993 Anesthesia Apparatus Checkout Recommendations?

A)  FDA

B)  American Medical Association (AMA)

C)  ASA

D)  A and C

E)  All of the above

Answer: D

In 1993, a joint effort between the American Society of Anesthesiologists (ASA) and the U.S. Food and Drug Administration (FDA) resulted in the 1993 FDA Anesthesia Apparatus Checkout Recommendations. The ASA is the principal body making safety recommendations in anesthesia, and the FDA is responsible for medical device regulation in the United States.

2.  All anesthesia machines have a check valve in the low-pressure system.

A)  True

B)  False

Answer: B

A check valve in the low-pressure system will negate a positive pressure leak test. A negative pressure leak test will be necessary to perform an adequate anesthesia machine checkout. Anesthesia technicians should consult the manufacturer’s operator manual for the presence of a low-pressure system check valve and the proper procedure for testing for leaks in this system.

3.  Piped gas pressure should be

A)  20-25 psig

B)  30-35 psig

C)  40-45 psig

D)  50-55 psig

E)  Greater than 55 psig

Answer: D

It is important to check for adequate pipeline supply pressure for all gases connected to the anesthesia machine. Although failure of pipeline pressure is rare, it can affect the delivery of gases to the patient and function of the ventilator.

4.  Who is qualified to perform portions of the anesthesia machine check?

A)  Anesthesia care provider

B)  Anesthesia technician

C)  Biomedical technician

D)  A and B

E)  All of the above

Answer: E

The anesthesia provider is responsible for the anesthesia machine check and ensuring the adequacy of its function. However, the provider can delegate this task, or parts of this task, to an anesthesia technician or biomedical engineering technician at the provider’s discretion: the provider, however, is ultimately responsible for the machine and the patient being cared for with that machine.

5.  How often should the breathing system pressure and leak testing be performed?

A)  Once per day

B)  Prior to the start of each case

C)  Anytime the circuit is changed

D)  A and B

Answer: D

The breathing system pressure and leak testing should be performed before the start of each case. If a day has multiple cases, some of which are MAC cases and the circuit is not changed, the anesthesia provider is still responsible for checking that there is a working source of positive pressure before each case. Similarly, if an operating room in an obstetric or trauma suite remains set up for a few days, unused but awaiting a possible emergency general anesthetic at any moment, breathing system pressure and leak testing is done once per day.

6.  Vaporizers should

A)  Be checked for adequate agent prior to each case

B)  Have filler ports tightened after filling to prevent leakage

C)  Never be tipped

D)  B and C only

E)  All of the above

Answer: E

Not only should the vaporizers be checked for adequate agent prior to each case but, after filling, the filler ports should be tightened. Vaporizers should never be tipped, as tipping may cause the internal wick to become saturated and the delivery concentration could become inaccurate.

7.  True or False? If an anesthesia machine passed its automated checkout, any problem (e.g., very high pressures without ventilation after intubation or very low compliance and a large gas leak) cannot be a problem in the checked out anesthesia machine.

A)  True

B)  False

Answer: B

An automated checkout does not rule out either a malfunction in an item not included in the machine checkout or a failure of the checkout process. A malfunction in the interaction between the human and the machine is also a possibility: some difficulty with machine setup or configuration. A “passed” automated checkout also does not rule out the possibility of a malfunction that begins after the checkout is completed.

8.  True or False: Anesthesia technologists do not need to be familiar with the intricacies of the anesthesia machine because anesthesia providers are responsible for diagnosing and managing equipment malfunctions and failures.

A)  True

B)  False

Answer: B

Anesthesia providers are responsible for diagnosing and managing equipment malfunctions and failures, in collaboration with the anesthesia technologist. In a circumstance where the anesthesia machine is failing to provide adequate ventilation, adequate anesthesia gas, or adequate monitoring, the anesthesia provider first needs a substantial amount of attention just to re-establish these patient care tasks of the anesthesia machine (monitor, ventilate, anesthetize) before attempting a diagnosis or repair of the machine. This is where the advanced skills of the AT at diagnosis and repair of the machine are invaluable.

SUGGESTED READINGS

Ben-Menachem E, et al. Identifying and managing technical faults in the anesthesia machine: lessons learned from the Israeli Board of Anesthesiologists. Anesth Analg. 2011;112:864-866.

Brockwell RC, et al.; for American Society of Anesthesiologists. Recommendations for Pre-Anesthesia Checkout Procedures. 2008. Available from: http://www.asahq.org/For-Members/Clinical-Information/~/media/For%20Members/Standards%20and%20Guidelines/FiNALCheckoutDesignguidelines.ashx

Dorsch JA, Dorsch SE. Understanding Anesthesia Equipment. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008.

Edward MG, Mikhail MS, Murray MJ. Clinical Anesthesiology. 3rd ed. New York, NY: McGraw-Hill; 2003.

Hilton G, et al. Failure to ventilate with the Dräger Apollo® Anesthesia Workstation. Anesthesiology. 2011;114:1238-1240.

Miller RD. Miller’s Anesthesia. 7th ed. Philadelphia, PA: Churchill Livingstone; 2009.

Standards for Basic Anesthetic Monitoring, Committee of Origin: Standards and Practice Parameters (Approved by the ASA House of Delegates on October 21, 1986, and last amended on October 20, 2010, with an effective date of July 1, 2011).