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Resuscitator

A resuscitator, also known as a bag-valve-mask (BVM), is a portable, hand-operated medical device designed to deliver positive pressure ventilation to patients experiencing respiratory failure or apnea, by manually inflating their lungs with oxygen-enriched air.^[1] It typically consists of a self-inflating bag, a one-way valve system to prevent rebreathing of exhaled gases, and an interface such as a face mask or endotracheal tube, enabling emergency providers to oxygenate and ventilate individuals who cannot breathe spontaneously.^[2] These devices are essential in settings like cardiopulmonary resuscitation (CPR), trauma care, and anesthesia, where immediate respiratory support can be lifesaving.^[3] The modern resuscitator was invented in 1953 by Danish anesthesiologist Henning Ruben and engineer Holger Hesse amid a polio epidemic in Denmark, which created a surge in demand for manual ventilation tools during an oxygen shortage caused by a national truck drivers' strike.^[4] Launched commercially in 1956 as the Ambu bag by Testa-Laboratorium (later renamed Ambu), it was the first self-inflating manual resuscitator, featuring a simple design with a latex bulb reinforced by bicycle spokes (later replaced by foam rubber) that required no external power source or oxygen supply for basic function.^[4] This innovation addressed the limitations of earlier bellows-style devices from the early 20th century, such as the Dräger Pulmotor of 1907, which were bulky, oxygen-dependent, and prone to fatigue during prolonged use.^[5] By the 1960s, the Ambu bag had largely supplanted these predecessors, becoming a standard in emergency medicine due to its reliability, portability, and ease of sterilization.^[4] Resuscitators are classified primarily into self-inflating and flow-inflating types, with the former—exemplified by the Ambu bag—relying on elastic recoil to automatically refill the bag with ambient air after compression, making it ideal for prehospital and resource-limited environments.^[6] Flow-inflating models, in contrast, require a continuous oxygen source to inflate the bag and are often used in controlled clinical settings for more precise tidal volume delivery.^[6] Available in adult and pediatric sizes, with the latter incorporating pop-off valves to limit pressure and prevent barotrauma in infants and children, resuscitators are constructed from durable, latex-free materials to minimize infection risks and ensure single-patient use in disposable variants.^[7] In clinical practice, resuscitators facilitate positive pressure ventilation at rates of 10–12 breaths per minute for adults, delivering tidal volumes of 400–600 mL while monitoring for chest rise and avoiding hyperventilation, which can complicate CPR outcomes.^[3] They integrate with advanced airway devices like supraglottic airways or laryngoscopes and are often equipped with accessories such as positive end-expiratory pressure (PEEP) valves to improve oxygenation in conditions like acute respiratory distress syndrome (ARDS).^[8] Despite their simplicity, effective use demands training to achieve proper mask seal and ventilation technique, underscoring their role as a foundational tool in global emergency response protocols.^[9]

Overview

Definition and Purpose

A resuscitator is a portable medical device that delivers positive pressure ventilation to patients with inadequate or absent spontaneous breathing, helping to prevent hypoxia and maintain adequate oxygenation.^[7]^[1] These devices function by forcing oxygen-enriched air into the lungs via a mask, tube, or other interface, restoring respiratory function in critical situations where normal breathing has ceased.^[10] The primary purposes of resuscitators encompass immediate airway management during cardiac arrest, acute respiratory failure, or trauma, where rapid intervention is essential to sustain life.^[3] They also serve as a temporary bridge to more advanced mechanical ventilation systems in clinical settings and are employed by emergency medical responders in both pre-hospital and hospital environments to support patients until definitive care is available.^[11]^[12] In global emergency protocols, such as those from the American Heart Association, bag-valve-mask resuscitators are the standard for initial ventilation during out-of-hospital cardiac arrest, forming a core component of basic life support.^[12]

Basic Components

A standard resuscitator, also known as a bag-valve-mask (BVM) device, comprises several core components that enable manual positive pressure ventilation to support breathing in patients unable to ventilate adequately. These include a self-inflating bag serving as the primary reservoir for air or oxygen, one-way valves to direct gas flow and prevent rebreathing, a patient interface for delivering gas to the airway, and an oxygen inlet port for supplemental oxygen delivery.^[3]^[13] The self-inflating bag is the central element, constructed to recoil automatically after compression, drawing in fresh gas from the environment or an oxygen source to refill itself. It typically has a capacity of 500 mL for pediatric use and 1,500–1,600 mL for adults, allowing delivery of tidal volumes around 300–800 mL depending on squeeze force and patient size. This design ensures reliable inflation without external power, facilitating intermittent or continuous ventilatory support.^[3]^[14] One-way valves are integral to unidirectional gas flow: the intake valve, often featuring flap or disc membranes, admits fresh air or oxygen into the bag while blocking backflow; the patient valve, including non-rebreathing mechanisms like duckbill or single-shutter valves, directs exhaled gas away from the patient to prevent re-inhalation of carbon dioxide-enriched air. These valves maintain low resistance—typically 2–4 cmH₂O for inspiration and expiration—to minimize work of breathing during operation.^[3]^[14] The patient interface consists of a face mask that seals over the mouth and nose or a standard 15 mm connector for attachment to an endotracheal tube, ensuring targeted delivery of ventilatory gases directly to the airway. Masks are sized variably (e.g., sizes 0–5 for infants to adults) to achieve an airtight seal without excessive pressure on facial tissues.^[3]^[14]^[15] An oxygen inlet port, usually a nipple or tubing connector, allows attachment to an external oxygen supply, often with a reservoir bag (600 mL pediatric, 2,600 mL adult) to achieve FiO₂ levels up to 100% at flows of 10–15 L/min. Without oxygen, the device delivers room air (21% FiO₂); with a reservoir and high flow, oxygenation improves significantly for hypoxic patients.^[3]^[14] Resuscitators are typically fabricated from biocompatible, durable materials such as silicone for reusable models, which can withstand autoclaving for sterilization, or polyvinyl chloride (PVC) for disposable versions to ensure single-use sterility and cost-effectiveness. These materials provide flexibility for bag compression, chemical resistance, and latex-free composition to reduce allergy risks. Bag capacities and valve dead spaces (around 7 mL) are standardized to support safe ventilation across age groups.^[3]^[16]^[14] In terms of flow dynamics, squeezing the bag manually generates positive airway pressure, commonly 10–40 cmH₂O, to inflate the lungs with tidal volumes of 6–7 mL/kg ideal body weight, delivered over 1–2 seconds at rates under 12 breaths per minute. This creates a pressure gradient that drives gas through the valves and interface, with exhalation occurring passively as the bag refills and chest recoil expels CO₂ via the outlet valve. Excessive squeeze can exceed safe limits, risking barotrauma.^[15]^[17]^[18] Variations in setup enhance safety in advanced models: a pop-off valve, often set at 35–60 cmH₂O, automatically vents excess pressure to protect against lung overdistension, particularly in pediatric devices; some integrate a pressure manometer to monitor real-time airway pressures, aiding precise control during use. These features are optional but recommended for high-risk scenarios to maintain pressures below 30–40 cmH₂O.^[3]^[14]^[11]

Types of Resuscitators

Manual Resuscitators

Manual resuscitators, commonly known as bag-valve-mask (BVM) devices, are hand-operated tools designed for providing positive pressure ventilation to patients who are not breathing adequately. These devices consist of a self-inflating bag connected to a one-way valve system and a face mask, allowing a single operator or team to deliver controlled breaths without relying on external power sources. The Ambu bag, a widely recognized proprietary example, exemplifies this design and has become synonymous with manual resuscitation efforts in emergency settings.^[17] The core design features a compressible, self-inflating reservoir bag made from durable, medical-grade materials like SEBS, with an adult-sized bag typically holding a volume of 1.5 to 2 liters. Integrated non-rebreathing valves ensure unidirectional airflow, preventing exhaled gases from re-entering the bag while allowing intake from ambient air or an attached oxygen reservoir. When squeezed, the bag delivers a tidal volume of approximately 500-600 mL for adults, adjustable based on squeeze force and duration, which supports effective lung inflation without excessive pressure. This configuration enables compatibility with various mask sizes for airtight seals over the nose and mouth.^[19]^[17]^[20] In operation, the rescuer rhythmically squeezes the bag to force air or oxygen-enriched gas into the patient's lungs via the mask, with the bag automatically refilling upon release through intake valves drawing from the environment or reservoir. For adult patients, ventilations are typically administered at a rate of 10-12 breaths per minute, each lasting 1 second to mimic natural respiration and minimize risks like barotrauma. The device's simplicity allows for immediate use in diverse scenarios, from prehospital care to operating rooms, bridging the gap until advanced airway management is available.^[17]^[21] Key advantages of manual resuscitators include their portability and reliability in resource-limited environments, as they require no electricity or batteries and can function solely with room air if oxygen is unavailable. Production costs are low, with disposable adult units often priced under $20, making them accessible for widespread deployment in emergency kits and ambulances. When used correctly, they achieve effective ventilation in the majority of cases, supporting oxygenation and carbon dioxide removal until more definitive interventions, though operator skill is crucial to avoid complications like gastric insufflation.^[4]^[22]^[21] The invention of the manual resuscitator traces back to Danish anesthesiologist Henning Ruben, who invented the first self-inflating bag in 1953 amid an oxygen supply crisis in Denmark, with commercial launch in 1956, revolutionizing portable manual ventilation by eliminating the need for compressed gases or electrical power.^[23]^[24]^[4]

Expired Air Resuscitators

Expired air resuscitators are basic ventilation devices designed for mouth-to-mask or mouth-to-barrier delivery, utilizing the rescuer's exhaled breath to provide positive pressure ventilation to a non-breathing patient. These devices feature a transparent mask that seals over the patient's mouth and nose, incorporating a one-way flutter valve and outflow valve to direct the rescuer's expired air into the patient's airway while preventing reverse flow of the patient's exhaled gases back to the rescuer. An inflow valve allows the rescuer to draw in fresh room air between breaths, and some early designs included a relief valve to limit pressure and avoid barotrauma; modern devices rely on proper rescuer technique for pressure control. Unlike powered or bag-based systems, these resuscitators require no external equipment or power source, relying entirely on the rescuer's manual exhalation and lung capacity to generate tidal volumes typically limited to 500-800 mL per breath, though effective delivery of approximately 500 mL (6-7 mL/kg for adults) is recommended to ensure adequate ventilation without excessive gastric insufflation.^[25]^[26]^[27] In operation, the rescuer places the mask securely on the patient's face and exhales steadily through the device at a controlled rate of 10-12 breaths per minute, observing chest rise to confirm effective delivery. The exhaled air provides an oxygen concentration of approximately 16-17%, sufficient for short-term oxygenation in emergencies, as it maintains alveolar oxygen tension around 80 mm Hg. One-way valves and optional bacterial/viral filters (with up to 99.8% efficiency) minimize cross-infection risks by blocking pathogens from the patient's respiratory tract. This method is particularly suited to resource-limited settings, such as layperson interventions during cardiac arrest or respiratory failure.^[26]^[28]^[25] The primary advantages of expired air resuscitators include their immediate availability in standard CPR kits, portability, and zero risk of mechanical failure, making them ideal for bystander resuscitation as endorsed by American Heart Association (AHA) guidelines since the 1950s. They enable rapid initiation of ventilation without specialized training beyond basic CPR instruction, historically validated for maintaining oxygenation in scenarios like drowning or asphyxia. However, prolonged use carries a risk of hypercapnia in the patient due to the 3.5-4.1% carbon dioxide content in the rescuer's exhaled air, which can inhibit cardiac function and elevate blood CO2 levels over time. Additionally, in infectious disease outbreaks, these devices are unsuitable without robust barriers, as the close proximity increases transmission potential despite valves, with rare documented cases of pathogens like Helicobacter pylori or tuberculosis crossing during mouth-to-mask contact.^[29]^[28]^[28]

Oxygen-Powered Resuscitators

Oxygen-powered resuscitators are medical devices that utilize compressed oxygen or air from a cylinder to automate the delivery of positive pressure ventilation, making them ideal for scenarios requiring sustained or hands-free support in critical care settings. These systems typically employ a demand valve mechanism or continuous flow design connected directly to an oxygen source, such as an E-cylinder regulator, enabling the provision of high-concentration oxygen—ranging from 40% to 100%—at adjustable flow rates up to 30 liters per minute (L/min).^[30]^[31] The lightweight and compact construction, often weighing under 0.5 kg and measuring around 140 x 63 x 73 mm, facilitates portability without reliance on batteries or electrical power.^[31] In operation, these resuscitators initiate ventilation through patient-triggered demand or fixed-time cycling, with modes selectable for manual override or automatic delivery at rates of 10-20 breaths per minute (BPM). Pressure is inherently limited to 40-60 cmH₂O to prevent barotrauma, achieved via built-in relief valves that terminate flow upon reaching the threshold, accompanied by an audible alarm for high pressure or obstructions.^[30]^[31]^[32] Additional safety features include positive end-expiratory pressure (PEEP) options of 2-4 cmH₂O and compatibility with masks, endotracheal tubes, or tracheostomies for patients over 10 kg. Low-pressure alarms may activate if the oxygen supply drops below 30 L/min, ensuring reliable performance during use.^[30] Key advantages of oxygen-powered resuscitators include significant reduction in rescuer fatigue by automating consistent tidal volume delivery, precise control over inspiratory flows to minimize gastric insufflation, and their suitability for ambulance transport where hands-free operation allows focus on other interventions.^[33]^[34] These devices support minute volumes of 9-18 L/min in automatic mode, enhancing oxygenation efficiency in prehospital environments.^[31] Tidal volume is determined by the equation:

\text{Tidal volume} = \text{Flow rate} \times \text{Inspiratory time}

For instance, at a flow rate of 15 L/min (0.25 L/s) and an inspiratory time of 1 second, this yields approximately 250 mL, scalable to adult needs of 500 mL or more by adjusting parameters.^[31] Early models from the 1960s, such as those developed by companies like Bird and Bennett, began integrating oxygen-powered features with basic ventilatory systems to improve reliability in emergency settings.^[35]

Historical Development

Early Innovations

Early efforts in mechanical resuscitation predated the 20th century, with bellows devices emerging as rudimentary tools for artificial ventilation, particularly in response to mining accidents where asphyxiation from toxic gases was common. These bellows, often paired with simple masks, were used to force air into victims' lungs, marking an initial shift from manual methods toward mechanical assistance in industrial emergencies.^[36] In the 1740s, English physician John Fothergill advanced these concepts by advocating the use of bellows to distend the lungs of apparently drowned individuals, reporting William Tossach's successful 1744 case of mouth-to-mouth insufflation to restore breathing in a suffocated coal miner, while advocating mouth-to-mouth respiration as a preferred method for reviving apparently drowned individuals over bellows due to its availability and controlled force. Fothergill's work emphasized the physiological need for lung inflation to revive asphyxiated patients, influencing subsequent European resuscitation practices focused on drowning and suffocation.^[37]^[38] The early 20th century saw the introduction of more sophisticated mechanical resuscitators, exemplified by the 1907 Pulmotor developed by Heinrich Dräger in Germany. This portable device, powered by pressurized oxygen, alternated positive and negative airway pressures to simulate breathing for asphyxiation victims, and it was the first commercially produced ventilator of its kind. Mass production ramped up in the 1910s, with widespread deployment during World War I for treating gas poisoning and battlefield injuries.^[39]^[40] By the 1920s, precursors to the iron lung, such as earlier negative-pressure chamber designs, began influencing the evolution toward more reliable portable resuscitators, though these early innovations suffered from significant limitations including bulkiness, which hindered mobility, and unreliability in consistent pressure delivery, often leading to inadequate ventilation or patient injury. Despite these challenges, the adoption of such devices in regions with high incidences of drowning and industrial accidents contributed to substantial reductions in mortality rates for respiratory emergencies, transforming outcomes from near-certain fatality to viable recovery in many cases.^[41]^[42]

Mid-20th Century Advancements

In the 1950s, a pivotal advancement in resuscitator design emerged with the invention of the self-inflating bag by Danish anesthesiologist Henning Ruben and engineer Holger Hesse, introduced commercially in 1956 as the Ambu bag.^[23] This device represented the first portable, disposable resuscitator featuring non-rebreathing valves, including the innovative Ruben valve, which allowed for efficient one-way airflow without the need for external gas sources or electricity, enabling reliable manual ventilation in resource-limited settings.^[24] Unlike earlier bellows-based systems, the Ambu bag's lightweight rubber construction—initially weighing around 500 grams—facilitated immediate use by a single operator, marking a shift toward user-friendly, field-deployable tools that enhanced emergency response capabilities post-World War II.^[4] During the 1960s and 1970s, further refinements focused on improving safety, monitoring, and compatibility, including the integration of oxygen inlet ports to deliver enriched air mixtures up to 100% oxygen, which addressed limitations in hypoxic environments.^[43] A significant material transition occurred from durable but cumbersome metals and rubbers to lightweight plastics like polyvinyl chloride (PVC), promoting disposability, easier sterilization, and reduced infection risk in clinical and prehospital settings.^[43] These changes drastically lowered device weight from over 5 kg in prior metal-framed models, such as early 20th-century Pulmotors, to under 1 kg, boosting portability for ambulance crews and first responders.^[5] Key milestones in standardization came in the 1970s, when the American Heart Association (AHA) endorsed the inclusion of BVM resuscitators in cardiopulmonary resuscitation (CPR) protocols as part of advanced life support training, building on its 1963 formal adoption of CPR techniques.^[29] This endorsement, alongside the 1979 National Conference on CPR and Emergency Cardiac Care, accelerated the integration of BVMs into global emergency guidelines, emphasizing their role in maintaining oxygenation during cardiac arrest.^[44] By the late 1970s, these portable, reliable devices had achieved widespread adoption in emergency medical services, contributing to enhanced survival outcomes in out-of-hospital cardiac arrests through more effective ventilation support.^[45]

Clinical Applications

Indications for Use

Resuscitators, such as bag-valve-mask (BVM) devices, are primarily indicated for managing apnea during cardiac arrest, where immediate ventilatory support is essential to maintain oxygenation and circulation.^[15] They are also deployed in cases of severe hypoxia, such as peripheral oxygen saturation (SpO2) below 90% despite supplemental oxygen, to prevent further deterioration in tissue perfusion.^[46] Additional primary indications include airway obstruction from foreign bodies or anatomical issues, and respiratory compromise induced by trauma, such as chest injuries impairing ventilation.^[15] In specific clinical scenarios, resuscitators play a critical role in out-of-hospital cardiac arrest (OHCA), where BVM ventilation is a standard component of basic life support protocols to deliver oxygen during chest compression pauses.^[47] Perioperative emergencies, including respiratory failure during anesthesia induction or recovery, often necessitate their use to bridge until intubation or recovery of spontaneous breathing.^[15] For neonatal resuscitation, positive pressure ventilation via resuscitator is recommended if heart rate remains below 100 beats per minute after initial drying and stimulation, with particular considerations for preterm infants who may require adjusted oxygen concentrations.^[48] Evidence-based criteria for initiation include absent respirations (apnea) or severe hypoventilation in adults that compromises gas exchange.^[15] Ventilation should continue until spontaneous breathing resumes, an advanced airway is secured, or return of spontaneous circulation is achieved, with monitoring for chest rise and improving SpO2 to confirm efficacy.^[15] Contraindications to resuscitator use include an intact gag reflex without prior sedation, as this increases the risk of vomiting and aspiration during mask application.^[15] Resuscitators are not suitable for chronic or long-term ventilation, as they are designed for acute, intermittent support rather than sustained mechanical assistance.^[15]

Operation Techniques

Operation of a resuscitator, such as a bag-valve-mask (BVM) device, begins with proper setup to ensure airway patency and effective delivery of oxygen-enriched air. Select the appropriate mask size based on the patient's age—adult masks for patients over 8 years or weighing more than 20 kg, pediatric for younger children, and infant masks for neonates and small infants—to achieve a secure seal without excessive pressure on the face. Attach the mask to the self-inflating bag and connect an oxygen source if available, delivering at least 15 L/min to achieve high inspired oxygen concentrations up to 100%. Position the patient supine and perform the head-tilt/chin-lift maneuver to open the airway, or use jaw thrust if cervical spine injury is suspected; insert an oropharyngeal airway in unresponsive patients without a gag reflex or a nasopharyngeal airway if semi-conscious to prevent obstruction.^[11]^[21]^[15] The ventilation sequence involves delivering controlled breaths to mimic normal respiration while avoiding barotrauma. Squeeze the bag firmly but slowly over approximately 1 second to deliver a tidal volume of 6-7 mL/kg of ideal body weight—typically 400–600 mL for adults, 4–8 mL/kg (e.g., 15–30 mL for term neonates) for newborns, and 6–7 mL/kg for older infants and children—observing for visible chest rise as the primary indicator of adequate delivery. Administer breaths at a rate of 10–12 per minute for adults (one every 5–6 seconds), 20–30 per minute for infants and children, and 30–60 per minute for neonates (as of 2025 AHA guidelines).^[48]^[12]^[15]^[11] Allow full exhalation between breaths by releasing the bag completely, and avoid excessive force to prevent gastric insufflation.^[12]^[15]^[11] Continuous monitoring during operation is essential to adjust technique and prevent complications. Assess for symmetric chest rise and bilateral breath sounds after each breath to confirm lung inflation; watch for signs of gastric distension, such as abdominal movement or regurgitation, which may indicate improper mask seal or excessive pressure. Check for air leaks around the mask by listening for hissing sounds and readjust the seal as needed, using pulse oximetry or capnography if available to target oxygen saturation above 94% and end-tidal CO2 between 35-45 mm Hg. If leaks persist, reposition the head or switch to a two-person technique.^[21]^[15]^[11] For advanced scenarios, employ a two-person technique to enhance seal efficacy and reduce operator fatigue, where one provider maintains the mask seal using both hands (e.g., thumbs on the mask connector and fingers lifting the mandible) while the second squeezes the bag. This method delivers more consistent tidal volumes compared to one-person operation. When integrating with cardiopulmonary resuscitation (CPR), deliver two breaths after every 30 chest compressions in adults (30:2 ratio) until an advanced airway is placed, then transition to asynchronous ventilation at 10 breaths per minute without interrupting compressions. In pediatric CPR (infants and children), use a 15:2 ratio for two rescuers or 30:2 for one rescuer (as of 2025 AHA guidelines).^[49]^[21]^[15]

Modern Innovations and Guidelines

Recent Technological Advances

In response to the COVID-19 pandemic, significant innovations in automated resuscitators emerged post-2010, focusing on low-cost, portable designs to bridge ventilator shortages in overwhelmed healthcare systems. These devices automate the compression of bag-valve masks (BVMs), providing consistent ventilation without requiring constant manual effort. Notable examples include the MIT Emergency-Vent, a robotic gripper-based system developed in 2020 to deliver controlled breaths at a production cost of approximately $100–$200, and the RepRapable automated BVM, which uses off-the-shelf and 3D-printed components for rapid assembly in resource-limited environments.^[50]^[51]^[52] Other NIH-supported research highlighted designs like the ABCD ventilator, costing around $400–$800 in production, emphasizing portability and ease of assembly for emergency use.^[52] Modern automated resuscitators incorporate smart features such as integrated pressure and flow sensors for real-time tidal volume monitoring, achieving accuracies of ±8% or better in validated systems, which helps prevent over- or under-ventilation.^[53] Battery-powered models, like the AuRes automatic resuscitator, offer 2 hours of continuous operation on battery, suitable for short-term field or transport scenarios.^[54] While AI-driven rate adjustments remain more prevalent in full ventilators, resuscitator prototypes have adopted automated feedback loops to maintain respiratory rates based on sensor data, enhancing reliability during crises.^[52] Key innovations include hybrid manual-automatic modes, as seen in devices like the OP-Vent, which allow seamless switching between operator-squeezed and mechanized compression for adaptive clinical needs. Disposable single-use variants, such as the Ambu SPUR II and Dispo-Bag resuscitators, utilize medical-grade, latex-free materials to minimize infection risks, proving essential for pandemic protocols and single-patient applications. Additionally, 3D-printable prototypes, exemplified by the AIR (Automated Inflating Resuscitator), enable on-demand production in disaster zones using accessible printers and materials.^[52]^[55]^[56]^[57] These advances have facilitated greater adoption in low-resource settings, where manual ventilation often leads to inconsistent delivery. Field trials and bench evaluations, including a 2022 biological study on mechanical resuscitators, demonstrated stable tidal volumes and effective oxygenation maintenance in porcine models, outperforming manual methods in consistency and reducing clinician fatigue. A 2024 implementation study in resource-constrained areas, such as on the Unisabana-HERONS low-cost mechanical ventilator in Colombia, further confirmed stable arterial blood gases (PaO2 ~69-80 mmHg, PaCO2 ~38-40 mmHg) and SpO2 levels (~94-96.8%) comparable to standard ventilators, supporting their role in improving outcomes during outbreaks and emergencies.^[58]^[59]^[52]

Current Standards and Training

Current international guidelines for resuscitator use emphasize standardized protocols to optimize outcomes in cardiac arrest scenarios. The 2025 American Heart Association (AHA) guidelines recommend bag-valve-mask (BVM) ventilation as a primary basic airway management strategy during out-of-hospital cardiac arrest (OHCA), delivering sufficient tidal volume (approximately 500–600 mL) to achieve visible chest rise while avoiding excessive ventilation that could lead to gastric insufflation or reduced cardiac output.^[12] Similarly, the European Resuscitation Council (ERC) Guidelines 2025 endorse BVM as essential equipment for standard CPR in OHCA, prioritizing it alongside chest compressions in the initial response algorithm.^[60] In low-income settings, the World Health Organization (WHO) standards advocate for manual resuscitators, such as self-inflating bag-and-mask devices, as the cornerstone of basic neonatal and adult resuscitation due to their simplicity, reusability, and minimal resource requirements.^[61] Training protocols for resuscitator proficiency are integrated into Basic Life Support (BLS) certification programs, which mandate hands-on sessions to build competency. AHA-accredited BLS courses typically include approximately 2 hours of practical training using simulation manikins to practice BVM techniques, team dynamics, and scenario-based application, ensuring rescuers can maintain an airtight seal and deliver appropriate ventilation rates of 10 breaths per minute without interrupting compressions.^[62] These sessions emphasize skill retention through deliberate practice, with certification requiring demonstrated competence in adult, child, and infant scenarios. Recertification is required every 2 years to reinforce these skills, as proficiency can decline without regular refreshers.^[62] Regulatory frameworks ensure resuscitators meet safety and performance benchmarks. In the United States, the Food and Drug Administration (FDA) classifies manual resuscitators as Class II devices, subjecting them to 510(k) premarket notification and general controls to mitigate moderate risks associated with ventilation delivery.^[63] Internationally, the ISO 80601-2-84:2023 standard specifies requirements for basic safety and essential performance of emergency medical services ventilators, including resuscitators, through rigorous testing of flow accuracy, pressure limits, and alarm functions to support reliable use in prehospital environments.^[64] Following the COVID-19 pandemic, virtual reality (VR) training modules for resuscitation skills have gained traction, with over 30% of medical education programs incorporating them by 2025 to enhance realism and accessibility while reducing infection risks during hands-on practice.^[65]

Limitations and Safety Considerations

Potential Risks

The use of resuscitators, particularly bag-valve-mask (BVM) devices, carries risks of barotrauma, defined as lung injury resulting from excessive airway pressure during ventilation. Clinical studies indicate that barotrauma, including pneumothorax and pneumomediastinum, occurs in approximately 13% of cases involving positive pressure ventilation over several days, with manual BVM contributing to acute instances through vigorous squeezing or inadequate pressure monitoring.^[66] This risk is heightened when peak inspiratory pressures exceed safe thresholds, potentially leading to alveolar rupture.^[67] Gastric insufflation represents another common complication, where air enters the stomach instead of the lungs, increasing the likelihood of regurgitation and aspiration. In scenarios involving BVM ventilation, gastric insufflation has been observed in up to 30% of cases, particularly with high tidal volumes or short inspiratory times, and can result in aspiration rates of 2.5% during intubation procedures.^[68]^[69] Untrained operators exacerbate this issue, as improper mask seal or excessive force promotes esophageal airflow.^[15] Device-specific risks include valve malfunctions in manual resuscitators, which can lead to rebreathing of exhaled carbon dioxide and subsequent hypoxia. Mis-assembly or defective non-rebreathing valves can cause inadequate ventilation or complete failure, resulting in hypoventilation and elevated carbon dioxide levels. In powered resuscitators, prolonged delivery of high fractional inspired oxygen (FiO2 >60%) poses a risk of oxygen toxicity, manifesting as pulmonary damage from reactive oxygen species and impaired gas exchange.^[70] This is particularly relevant in extended use, where hyperoxia can induce bronchitis-like symptoms and atelectasis.^[71] Patient-specific factors amplify these risks; pediatric patients, with their smaller and more compliant airways, face higher susceptibility to barotrauma and overdistension from standard adult devices.^[19] Additionally, expired air resuscitation methods historically carried infection transmission risks, but post-2020 guidelines incorporating personal protective equipment have significantly mitigated this concern during cardiac arrest scenarios.^[72] Complications during resuscitation are predominantly due to improper mask seals leading to hypoventilation or aspiration, as evidenced by observational data from emergency interventions.^[69]

Best Practices for Mitigation

To minimize risks associated with resuscitator use, preventive measures focus on device configuration and operational techniques. Pop-off valves on bag-valve-mask (BVM) resuscitators, particularly for pediatric use, should be set to limit peak inspiratory pressure to approximately 35 cmH₂O, preventing barotrauma while ensuring adequate tidal volumes (higher limits of 45-60 cmH₂O apply for adults).^[73] Implementing a two-rescuer technique, where one provider maintains a tight mask seal using both hands while the other squeezes the bag, reduces mask leaks by approximately 50% compared to single-rescuer methods, thereby improving ventilation efficacy.^[74] Regular device checks, including inspection for cracks, valve functionality, and mask integrity as per manufacturer guidelines (typically quarterly for reusable components and after each use for cleaning), ensure reliability and prevent equipment failure during emergencies.^[75] Infection control protocols have been strengthened following the COVID-19 pandemic, emphasizing disposable components to reduce cross-contamination. Single-use masks are recommended for BVM resuscitators in high-risk scenarios, as they eliminate the need for disinfection and minimize aerosol transmission of pathogens.^[76] For powered resuscitators, incorporating high-efficiency particulate air (HEPA) filters on the exhalation port captures viral particles, aligning with guidelines for aerosol-generating procedures.^[77] Monitoring protocols integrate continuous waveform capnography to verify effective ventilation, targeting an end-tidal CO₂ (ETCO₂) level greater than 10 mmHg, which confirms adequate pulmonary blood flow and chest compression quality during resuscitation. If BVM ventilation is required for more than 10 minutes without achieving stable oxygenation or if complications arise, transitioning to an advanced airway device, such as a supraglottic airway or endotracheal tube, is advised to sustain long-term support.^[47] In disaster settings, where resource scarcity is common, manual resuscitators like self-inflating BVMs are prioritized over powered units to conserve oxygen supplies and avoid dependency on electricity or compressed gas, which may be depleted or unavailable.^[78]

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Oct 14, 2025 · especially : a device used to restore or assist the respiration of a person who is not breathing normally. Medical Definition. resuscitator.
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How To Do Bag-Valve-Mask (BVM) Ventilation - Critical Care Medicine
Bag-valve-mask (BVM) ventilation is the standard method for rapidly providing rescue ventilation to patients with apnea or severe ventilatory failure.
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Part 7: Adult Basic Life Support: 2025 American Heart Association ...
Oct 22, 2025 · When ventilating adult patients in cardiac arrest, it is reasonable to give enough tidal volume to produce visible chest rise while avoiding ...
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The Self-Inflating Resuscitator – Evolution of an Idea - Sage Journals
In 177 AD, Galen used bellows to inflate the lungs of various animals. – “if when the animal is already dead, you blow air in through the larynx, you will of ...
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http://laerdalcdn.blob.core.windows.net/downloads/f2541/laerdal_silicone_resuscitator.pdf
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[PDF] Laerdal Silicone Resuscitators - NET
The Laerdal Silicone Resuscitator is a self-inflating manual resuscitator that is intended for patients requiring total or intermittent ventilatory support.
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Bag-Valve-Mask Ventilation - StatPearls - NCBI Bookshelf - NIH
May 3, 2025 · The tidal volume needed for an adult is typically 500 to 600 mL ... [15] Additionally, using low-pressure, low-volume insufflation ...Continuing Education Activity · Introduction · Preparation · Technique or Treatment
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[PDF] A HealthTech Report - PATH
Type of bag material: In general, resuscitator bags are produced in silicone, PVC, or rubber. Silicone is often the chosen material for reusable resuscitators ...<|separator|>
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Bag-Valve-Mask (BVM) Ventilation • LITFL • CCC Airway
Oct 6, 2024 · self-inflating resuscitation device · oxygen inlet nipple · air intake valve · oxygen reservoir with two one way valves · non-rebreathing valve that ...
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Manual bag valve mask ventilation performance among respiratory ...
Nov 1, 2020 · The mean ventilation parameters among all participants include a tidal volume of 599.70 ml, pressure of 26.35 cmH2O, flow rate of 26.35 l/min, ...
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It's In The Bag: Tidal Volumes in Adult and Pediatric Bag Valve Masks
The adult BVM provided a mean tidal volume of 807.7mL versus the pediatric BVM providing 630.7mL, both of which exceeded the upper threshold of 560mL of tidal ...
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BVM Air Volume Guide: Correct Ventilation Techniques |
Sep 5, 2025 · What is the recommended tidal volume for adult BVM ventilations? The American Heart Association recommends delivering 500-600 mL of air ( ...
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Bag-Valve-Mask Ventilation Technique - Medscape Reference
Jan 29, 2024 · This basic airway management technique allows oxygenation and ventilation of patients until a more definitive airway can be established.
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https://litfl.com/henning-ruben/
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Henning Ruben • LITFL • Medical Eponym Library
Dec 5, 2021 · This prompted Ruben, to conceive the idea of the self inflating bag designed to provide manual artificial ventilation without compressed gases.
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Ambu Bag - Wood Library-Museum of Anesthesiology (WLM)
In 1954, a shortage of oxygen deliveries to Danish hospitals prompted him to invent the first self-inflating resuscitator, the Air Mask Bag Unit (AMBU).
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MOUTH-TO-MASK RESUSCITATION - JAMA Network
Mouth-to-mask resuscitation uses a mask, flutter valve, and outflow valve to prevent expired air flow, and an inflow valve for fresh air. It is safe, simple, ...
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Part 6: Advanced Cardiovascular Life Support | Circulation
Rescue breathing (ventilation using exhaled air) will deliver approximately 16% to 17% inspired oxygen concentration to the patient, ideally producing an ...
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Mouth-to-mask ventilation: a superior method of rescue breathing
Mouth-to-mask ventilation produced tidal volumes (1,093 ml and 1,200 ml) not significantly different from those seen with endotracheal intubation. If clinical ...
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A Reappraisal of Mouth-to-Mouth Ventilation During Bystander ...
Studies have identified reticence to perform mouth-to-mouth ventilation as a significant barrier to more frequent performance of bystander CPR.
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History of CPR | American Heart Association CPR & First Aid
It's as old as the healing arts, as new as a drone delivering an automated external defibrillator (AED). And from primitive methods (like whipping an ...
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[PDF] CPR MEDICAL DEVICES INC. OPERATING MANUAL OXYLATOR ...
The OXYLATOR EMX is an oxygen powered resuscitator/ inhalator which requires no power source (i.e. battery) other than the supply of compressed oxygen in an ...
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[PDF] CAREvent® ALS - User Manual - O-Two Medical Technologies
Jul 19, 2023 · The CAREvent® ALS Handheld Resuscitator is a pneumatically powered, time/volume cycled ventilatory resuscitator with the added feature of a ...
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EMT Resuscitator - Allied Medical LLC
Advanced pneumatic technology limits and regulates gas flow to 40 lpm during the manually-triggered breath, but will allow flow rates of up to 115 lpm during a ...
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(PDF) The Effectiveness of Oxygen-Powered Inhalation Devices in ...
Jun 29, 2020 · An effective method for ventilation in such scenarios might be a triggered oxygen-powered resuscitator. Methods: We report seven ...Missing: function | Show results with:function
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Transport Ventilation | Respiratory Therapy
Oxygen driven resuscitators, also known as demand valves, may be found on an ambulance. These devices provide RCPs with the ability to ventilate the patient ...
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Early ICU Ventilators - Virtual Museum
The Bennett PR-2 was used often used to continuously ventilate patients in early ICUs. ... The Bird ventilators, such as the Bird Mark 7 pictured here, were used ...Missing: resuscitator | Show results with:resuscitator
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Breathing Apparatus for Mine Rescue in the UK, 1890s–1920s
Inspired in some respects by diving gear, the apparatus was used in mine rescue work and operations to recover mines after an explosion. The chapter focuses on ...
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[PDF] on the Recovery ofa Man Dead
a Man Dead in Appearance, by d/- tending the Lungs with Air. Printed at. Edinburgh, 1744; by John Fothergill,. Licent. Coll. Med. Lond. Read Feb. z1 ...
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ARTIFICIAL RESPIRATION, THE HISTORY OF AN IDEA
Fothergill, probably the greatest worker of this resuscitation ... Thus far the techniques of artificial respiration have entered the fields of physiology,.
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[PDF] It began with the Pulmotor The History of Mechanical Ventilation
His Pulmotor created positive and negative airway pressure alternatively and was powered by oxygen under pressure. In 1907. Heinrich Dräger was awarded the.Missing: steam- | Show results with:steam-
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Draeger Pulmotor - Wood Library-Museum of Anesthesiology (WLM)
The Pulmotor was introduced by the Draeger company, of Lubeck, Germany, in 1907. This example was made by a Draeger branch in Pittsburgh, PA.Missing: steam- | Show results with:steam-
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A practical mechanical respirator, 1929: the "iron lung" - PubMed
Popularly named the iron lung, the Drinker respirator supported thousands of patients afflicted with respiratory paralysis during the polio era.
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From Mouth‐to‐Mouth to Bag‐Valve‐Mask Ventilation: Evolution ...
May 27, 2014 · This paper draws a historical view of manual ventilation's evolution ... self-inflating bags to be used as complete resuscitation devices.
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Aug 7, 2025 · 238, 239 The first self-inflating resuscitator bag was designed by the Danish anesthesiologist Henning Ruben (1914Ruben ( to 2004)-the AMBU bag.Missing: invention | Show results with:invention
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US7051596B1 - Manual resuscitators with integral manometer
A manometer integrated into a manual resuscitator includes a housing with a communication path, and a pressure gauge integrally forming part of the housing.
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Standards and Guidelines for Cardiopulmonary Resuscitation (CPR ...
The National Conference on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiac Care (ECC) held in September 1979 developed standards and guidelines.
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Cardiopulmonary Resuscitation | Circulation
Dec 19, 2006 · The 2005 American Heart Association guidelines endorse rapid defibrillation, especially for inpatients, in which the goal is delivery of a ...
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Bag-Valve-Mask Ventilation and Survival From Out-of-Hospital ...
Nov 12, 2023 · This novel multicenter study demonstrates that lung inflation occurs infrequently with BVM ventilation during 30:2 CPR for OHCAs. Ventilation ...
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Part 5: Neonatal Resuscitation: 2020 American Heart Association ...
Oct 21, 2020 · Most newborns who are apneic or have ineffective breathing at birth will respond to initial steps of newborn resuscitation (positioning to open ...
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MIT volunteers created open-source, low-cost ventilator for Covid-19
Apr 22, 2020 · Engineers at the U of I developed a prototype for a simple emergency ventilator, called Rapid Vent, that would only cost $100 to $200 to make.
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Recent advances in low-cost, portable automated resuscitator ... - NIH
Dec 2, 2021 · Automated AMBU bags or resuscitator devices aim to assist patient breathing via compressing and releasing the AMBU bags at specific frequency, ...
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Introducing a novel respiratory function monitor for neonatal ...
The monitor automatically calculates and displays expiratory tidal volume (VTE) passing through the sensor with an accuracy of ±0.5 mL or ±8% and ventilation ...Simulation And Education · Introduction · Discussion<|control11|><|separator|>
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AuRes automatic resuscitator – Polbionica
The advantage of the AuRes automatic resuscitator is its lightweight housing, minimalist design, and battery sufficient for 2 hours of continuous operation.
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Ambu® SPUR®II Disposable Resuscitator
A disposable manual resuscitator featuring a single-shutter valve for reliable functionality, and a thin self-inflating bag with excellent recoil.Missing: infection COVID- 19
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Dispo-Bag™ Manual Resuscitator - GaleMed Corporation
Disposable for Single-Patient Use · Reduces the risk of cross-contamination—ideal for infection control protocols. · Latex-Free and Medical-Grade Materials · Safe ...
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Biological evaluation of a mechanical ventilator that operates by ...
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The development and implementation of a low-cost mechanical ...
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Evidence from several observational studies shows that facility-based basic neonatal resuscitation may avert 30% of intrapartum-related neonatal deaths.
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Resuscitator, Manual, Non Self-Inflating - Product Classification - FDA
A non self-inflating manual resuscitator, also called a hyperinflation system, is a manual ventilator intended to ventilate a patient by forcing a volume of ...
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ISO 80601-2-84:2023
### Summary of ISO 80601-2-84 for Resuscitators or Ventilators Performance Testing
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Part 12: Resuscitation Education Science: 2025 American Heart ...
Oct 22, 2025 · Virtual reality (VR) and augmented reality (AR) can increase realism during resuscitation training. However, while VR can improve knowledge ...
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Barotrauma and Mechanical Ventilation Treatment & Management
Feb 1, 2024 · In more than 900 patients with a cumulative incidence of barotrauma of 13% over the first 4 study days, no relation was detected between peak ...
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Sudden severe barotrauma from self-inflating bag-valve devices
These devices are generally safe, but minor deviations in their recommended use can expose patients to airway pressures greater than 135 cm H2O. We present a ...
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In several studies, the incidence of gastric insufflation varied from 0% to 30% depending on the PIP and the presence of a gastric tube. We hypothesized that ...Missing: untrained | Show results with:untrained
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Bag-Mask Ventilation during Tracheal Intubation of Critically Ill Adults
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Manual Resuscitators Flashcards | Quizlet
Defective/malfunctioning non-rebreather valve. III. Faulty pressure release valves. PEEP. Positive End-Expiratory Pressure. Common mechanical ventilator ...
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Damage from excessive oxygen can arise from both direct pulmonary toxicity from a high FiO2 and from systemic effects of high PaO2 in blood and tissues (5, 37) ...
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Practice of Excessive FIO2 and Effect on Pulmonary Outcomes in ...
Prolonged high FIO2 in patients requiring mechanical ventilation worsens gas exchange, decreases ciliary efficacy, and produces hyperoxic bronchitis and ...
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2023 International Consensus on Cardiopulmonary Resuscitation ...
In-water expired-air resuscitation may be considered by trained rescuers ... infection transmission and on consistency with current recommendations on using PPE ...
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Positive-Pressure Ventilation | Textbook of Neonatal Resuscitation
These valves are usually set to release at 30 to 40 cm H2O pressure, but they are not reliable and may not release until higher pressures are achieved. Some ...
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Oxygen Unit Maintenance | DAN Southern Africa
Jun 6, 2018 · Thoroughly inspect your unit at least once a month and after every use. Make sure the cylinder is not just full, but full of oxygen, and that the oxygen washer ...
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