Anesthesia Gas Delivery Research Articles

Assessment of Oxygen Gas Cylinder and Its Safety Measurement in Private Medical Care at Peshawar, Pakistan

Medical gas delivery equipment is a potential source of patient injury. Recent attention in health care has been on the architecture design of operation theater including equipment, technology, and patient safety. Oxygen cylinder failure is a rare but potentially cataphoric event that can affect the care of patients. Anesthetic gas delivery devices are a concern because they exhibit several basic features that may predispose to critical events and subsequent patient injury. This cross-sectional study was conducted among a sample of 267 from different private medical care centers in Peshawar through a convenience sampling technique from March 2018 to August 2018. A pretested questionnaire proforma was used for data collection. Ethical approval obtained from the head of the institute and a consent form was also signed from concern. Semi government and government hospital, central pipeline supply system was excluded from this study. Data were analyzed through SPSS version 22. A total of 267 oxygen cylinders were observed in which (n=165, 61.7%) cylinders were properly color-coded and the rest (n=102, 38.3%) were not. Of total, (23, 8.6%) cylinders were tested for compliance while 244 (91.3) were not tested, valve cap was present on (n=89, 33.3%), and rest of (n=178, 66.6%) were missing. Lifting (48%), was the major transport process. The least process was rolling (n=28, 10%). we concluded that all the ignorance which has been predominant in private medical care centers may pose a constant threat to the patient’s life and for the operating room team.

Can contemporary anesthesia gas delivery equipment malfunction: Look before you leap!

Can contemporary anesthesia gas delivery equipment malfunction: Look before you leap!

A case report of personal exposures to isoflurane during animal anesthesia procedures

ABSTRACTThe purpose of this study was to compare personal exposures to isoflurane from participants' breathing zone samples during animal anesthesia procedures by the method of anesthetic gas delivery and the waste anesthetic gas (WAG) control method utilized. WAG control methods included passive scavenging using charcoal canisters, active scavenging using a building vacuum system, and various local exhaust ventilation systems such as laboratory fume hoods and capture hoods. Methods of anesthesia delivery included induction chambers, face masks (also known as nose cones), and intubation. Personal breathing zone samples were collected using 3M 3520 Organic Vapor Diffusion Monitors and submitted to an International Organization for Standardization (ISO) 17025 accredited laboratory for analysis.When using face masks and induction chambers as the method of anesthesia delivery, local exhaust ventilation systems were found to be the best WAG control method to mitigate personal exposures to isoflurane. Personal exposures to isoflurane were well-controlled when animals were intubated, regardless of whether passive scavenging with an adsorptive charcoal canister or active scavenging with a building vacuum system was used. Personal exposures to isoflurane were highest when induction chambers and face masks were used for anesthesia delivery, and passive scavenging with adsorptive charcoal canisters were used as the control method. This study served to identify best practice WAG control methods for research and veterinary procedures that involve isoflurane anesthesia.

Mask Induction Despite Circuit Obstruction

Various equipment malfunctions of anesthesia gas delivery systems have been previously reported. Our profession increasingly uses technology as a means to prevent these errors. We report a case of a near-total anesthesia circuit obstruction that went undetected before the induction of anesthesia despite the use of automated machine check technology. This case highlights that automated machine check modules can fail to detect severe equipment failure and demonstrates how, even in this era of expanding technology, manual checks still remain essential components of safe care.

Patient Injuries From Anesthesia Gas Delivery Equipment

Mehta, Sonya P.*; Eisenkraft, James B.†; Posner, Karen L.*; Domino, Karen B.*‡ Author Information

Patient Injuries from Anesthesia Gas Delivery Equipment

Improvements in anesthesia gas delivery equipment and provider training may increase patient safety. The authors analyzed patient injuries related to gas delivery equipment claims from the American Society of Anesthesiologists Closed Claims Project database over the decades from 1970s to the 2000s. After the Institutional Review Board approval, the authors reviewed the Closed Claims Project database of 9,806 total claims. Inclusion criteria were general anesthesia for surgical or obstetric anesthesia care (n = 6,022). Anesthesia gas delivery equipment was defined as any device used to convey gas to or from (but not involving) the airway management device. Claims related to anesthesia gas delivery equipment were compared between time periods by chi-square test, Fisher exact test, and Mann-Whitney U test. Anesthesia gas delivery claims decreased over the decades (P < 0.001) to 1% of claims in the 2000s. Outcomes in claims from 1990 to 2011 (n = 40) were less severe, with a greater proportion of awareness (n = 9, 23%; P = 0.003) and pneumothorax (n = 7, 18%; P = 0.047). Severe injuries (death/permanent brain damage) occurred in supplemental oxygen supply events outside the operating room, breathing circuit events, or ventilator mishaps. The majority (85%) of claims involved provider error with (n = 7) or without (n = 27) equipment failure. Thirty-five percent of claims were judged as preventable by preanesthesia machine check. Gas delivery equipment claims in the Closed Claims Project database decreased in 1990-2011 compared with earlier decades. Provider error contributed to severe injury, especially with inadequate alarms, improvised oxygen delivery systems, and misdiagnosis or treatment of breathing circuit events.

Deep sedation with sevoflurane insufflated via a nasal cannula in uncooperative child undergoing the repair of dental injury

Sevoflurane, a potent volatile anesthetic, has been attempted to be used for procedural sedation. Because of lack of a commercially available sedation apparatus for sevoflurane administration, anesthetic gas delivery apparatus should be connected to general anesthetic machine for delivering sevoflurane gas. In this case, deep sedation was maintained during treatment of dental injuries involving the upper lip and incisor by sevoflurane insufflations via a nasal cannula. Especially, this may be advantageous in treating dental injuries involving upper lip and maxillary anterior teeth because the treatment is not disturbed during sevoflurane insufflations via a nasal cannula.

Intraoperative kinking of the intraoral portion of an endotracheal tube

Sir, Obstruction of the endotracheal tube can occur in various forms while the endotracheal tube is in situ.[1–3] We report a new cause of intra-oral kinking of the endotracheal tube. A 36-year-old, 55 kg, 158 cm patient was scheduled for modified right radical mastectomy for breast carcinoma. Anesthesia was induced with intravenous fentanyl (100 μg) and thiopentone (250 mg). Neuromuscular blockade achieved with vecuronium (5.5 mg) and trachea intubated with a 7.5 mm ID cuffed orotacheal tube (Rusch, Teleflex Medical Sdn Bhd, Malaysia). The tube was moved from the right angle of mouth and fixed on the left angle. The air entry was verified, by auscultation, to be bilaterally equal. The lungs were mechanically ventilated (volume-controlled mode with tidal volume 500 mL and respiratory rate 10 breaths/min) using Drager Primus Workstation (Drager Medical, Lubeck, Germany). The end-tidal carbon dioxide (EtCO2) was maintained at 35-38 mmHg and the airway pressure was 16 cmH2O. An hour after the start of surgery, airway pressures started rising and reached 44 cmH2O. Surgery was stopped. Chest auscultation revealed normal air entry with no signs suggestive of bronchospasm. The breathing circuit and the extraoral portion of the tube were checked and no kink was observed. The cuff pressure was 22 cmH2O. A suction catheter was passed through the endotracheal tube, but it could not be negotiated beyond the mid portion of the tube. Direct laryngoscopy was performed but no obvious kink was observed. The endotracheal tube was changed with a fresh endotracheal tube. On removal, an acute kink was observed about 10 cm above the cuff in a direction opposite to the natural curvature of the endotracheal tube (toward the convexity side) [Figures 1 and 2].Figure 1: Kinked endotracheal tubeFigure 2: Kinked endotracheal tubeIntraoperative difficulty in ventilation may result from anesthetic gas delivery malfunction, obstruction of the breathing circuit, poor pulmonary compliance (extrinsic or intrinsic), acute bronchospasm, tension pneumothorax, or endobroncial mass lesion.[4] Kinking of the tube has been mentioned as a cause for difficulty in ventilation. Kinking of the endotracheal tube has been reported at the cuff portion and at the point of insertion of the cuff inflation tube.[356] We wish to highlight a new cause of intraoral kinking of the tube which occurred sometime after the tracheal intubation. The shifting of the endotracheal tube from the right to the left angle of mouth could have led to a force acting in a direction perpendicular to the torque of the natural curve of the tube, thus kinking the tube. Thermal softening of the tube, on exposure to body temperature, promoted the kink and lead to difficulty in ventilation.[7] We observed that kinking of thermally softened tubes occurs more on bending it in the direction of the convexity of the tube than the concavity.

Towards international standardization of the anesthesia machine

THE practice of anesthesia and critical care has become increasingly dependent on medical technology. Almost every day we read articles in journals and newspapers and view on television some aspect of patient safety. It’s a trendy topic. Much is written on the fact that we must improve patient safety, but what is really being done about it? We have evolved from the old anesthesia machine which was a hodge-podge assembly of separate components, a Fluotec Mark II vaporizer, Ventimeter ventilator, Dial-a-Flo mixer, oxygen analyzer, low pressure alarm, one-channel electrocardiogram monitor, a manual mercury blood pressure cuff and stethoscope that was bolted together by a handyman in the basement of the hospital. We now have integrated anesthetic gas delivery and monitoring systems and in the future, the automated anesthesia glass cockpit. The term “standardization” when used in the context of making all equipment similar in design and function is really nowadays a misnomer. It’s just a small part of what medical equipment standards writers consider when writing a “standard”. What we are really trying to do is to write the minimum requirements for the “basic safety and essential performance” or in other words minimum engineering specifications for medical equipment in general; or for a particular device. Why the minimum, you may ask? Published standards must be sufficiently flexible to provide enough latitude to promote innovation. Standards that require the addition of numerous safety features increase the complexity of a device which may render the device unusable or more prone to failure. The law of diminishing returns takes over once again. An overview of standards development process has been published previously.1 There is no longer just one safety standard for the “anesthesia machine”, but a family of safety standards for almost every component of the “anesthesia system.”A In addition to the “particular” anesthesia system standard,B there are also additional standards covering radio frequency interference,C software, usabilityD and alarm systems.E Jeffrey Cooper in his classic article originally published in 1978 and reprinted in 2002 in the journal Quality and Safety in Health Care2 pointed out that only 14% of critical incidents in anesthesia were related to equipment failure, but 84% of preventable incidents were due to human error. Usability refers to the qualities of a device whereby it is easy to learn, easy to remember, and requires as few steps as possible to perform a task. Usability also implies that the system should have a low error rate and if errors are made, they should be easy to recognize and easy to fix. The device should be pleasant to use and should not frustrate or annoy the user. EDITORIAL 613

Keep It Flowing: A Simulation Involving Defective Anesthetic Gas Delivery Equipment

Keep It Flowing: A Simulation Involving Defective Anesthetic Gas Delivery Equipment

Problems with Anesthesia Gas Delivery Systems

Problems with Anesthesia Gas Delivery Systems

Hazards of anesthesia gas delivery systems

Hazards of anesthesia gas delivery systems

Anesthetic gas exposure in veterinary clinics.

Concerns were raised by several workers from veterinary clinics in Manitoba, Canada, regarding potential exposure to isoflurane and halothane during anesthetic administration. There has been no guideline established for isoflurane by the American Conference of Governmental Industrial Hygienist (ACGIH) or a Permissible Exposure Limit by the Occupational Safety and Health Administration (OSHA) or a recommended exposure limit (REL) by the National Institute for Occupational Safety and Health (NIOSH). The ACGIH TLV-TWA for halothane is 50 ppm and NIOSH has established 2 ppm as a recommended level based on an one-hour sampling. OSHA has established no guideline for halothane. The Miran IB Portable Ambient Air Analyzer was used to conduct real-time sampling and to identify leaks during administration. All veterinary clinics inspected had installed the passive waste gas scavenging system. Ten clinics were each monitored during anesthetic gas delivery for one surgical procedure performed. Induction was 4 to 5 percent and maintenance 1.5 to 2.5 percent. Nine clinics were small animal practices and the tenth was an equine clinic. Veterinarians' personal exposures were higher than the assistants'. Veterinarians' personal exposures for isoflurane ranged from 1.3 to 13 ppm (AM = 5.3; SD +/- 2.7; GM = 4.6; GSD +/- 1.6) and for their assistants, personal exposures ranged from 1.2 to 9 ppm (AM = 4.7; SD +/- 2.5; GM = 3.9; GSD +/- 1.6). Veterinarians' personal exposures for halothane ranged from 0.7 to 12 ppm (AM = 4.2; SD +/- 3.6; GM = 2.9; GSD +/- 1.4) and for their assistants, personal exposures ranged from 0.4 to 3.2 ppm (AM = 1.8; SD +/- 1.0; GM = 1.5; GSD +/- 1.7). One clinic had significant leaks in the anesthetic gas delivery lines. Personal halothane exposure for the veterinarian at this clinic was 7.2 to 65 ppm (AM = 18.0; SD +/- 11.5; GM = 15.9; GSD +/- 1.8). Based on this study, worker exposures were acceptable. Peak exposures were recorded when the cuffed endotracheal tube was removed from the animal. Equipment leaks were minimal when the system was maintained at its optimum operating condition.

Complications of Anesthesia Gas Delivery Systems

Complications of Anesthesia Gas Delivery Systems

Adverse Anesthetic Outcomes Arising from Gas Delivery Equipment

Anesthesia gas delivery equipment is a potentially important source of patient injury. To better define the contribution of gas delivery equipment to professional liability in anesthesia, the authors conducted an in-depth analysis of cases from the database of the American Society of Anesthesiologists Closed Claims Project. The database of the Closed Claims Project is composed of closed US malpractice claims that have been collected in a standardized manner. All claims resulting from the use of gas delivery equipment were reviewed for recurrent patterns of injury. Gas delivery equipment was associated with 72 (2%) of 3,791 claims in the database. Death and permanent brain damage accounted for almost all adverse outcomes (n = 55, 76%). Equipment misuse was defined as fault or human error associated with the preparation, maintenance, or deployment of a medical device. Equipment failure was defined as unexpected malfunction of a medical device, despite routine maintenance and previous uneventful use. Misuse of equipment (n = 54, 75%) was three times more common than equipment failure (n = 17, 24%). Misconnects and disconnects of the breathing circuit made the largest contribution to injury (n = 25, 35%). Reviewers judged that 38 of 72 claims (53%) could have been prevented by pulse oximetry, capnography, or a combination of these two monitors. Overall, 56 of 72 gas delivery claims (78%) were deemed preventable with the use or better use of monitors. The year of occurrence for claims involving gas delivery equipment ranged from 1962 to 1991 and did not differ significantly from claims involving other adverse respiratory events. Claims associated with gas delivery equipment are infrequent but severe and continue to occur in the 1990s. Educational and preventive strategies that focus on equipment misuse and breathing circuit configuration may have the greatest potential for enhancing the safety of anesthesia gas delivery equipment.

An Unusual Cause of Failure of Anesthetic Gas Delivery to a Patient Circuit

An Unusual Cause of Failure of Anesthetic Gas Delivery to a Patient Circuit