Essential Patient Safety


Essential Patient Safety


Essential Patient Safety


Pulmonary Barotrauma

A leading cause of iatrogenic anesthetic morbidity and mortality in small animal veterinary patients is pulmonary barotrauma.

Barotrauma has been shown to occur when airway pressures exceed as little as 30 cm of H2O but the threshold is species and likely breed specific. Once the airway pressure threshold is exceeded, alveoli rupture decreasing surface area for gas exchange. In severe cases the visceral pleura and large airways rupture leading to pneumothorax. The extreme intra-thoracic pressure also prevents venous return to the heart, ultimately leading to cardiac arrest. 

There is no effective treatment for this injury other than mechanical ventilation and supportive care for extended periods of time.

Anesthesia Machine Design Flaw

Most veterinary anesthetic machines do not have a safety pressure relief valve. The pop-off valve can perform this function but it is easily defeated by being manually closed during mechanical ventilation and during system pressure testing. If the operator forgets to re-open the valve, tragedy results.

The EMD Safety Valve is a simple solution to this problem. It cannot be manually defeated. It is passive in that it does not need to be turned on like pressure alarms do. It can be placed anywhere in the rebreathing breathing circuit.


The valve opens once the airway pressure exceeds approximately 26 cm H2O, bleeding off gas pressure, thereby preventing barotrauma. Pressure will remain open until the pop-off valve is opened or the patient is disconnected from the circuit.


All anesthetic machines should be equipped with a Safety Valve. Human error is unavoidable. This simple passive device will prevent a simple oversight from resulting in the death of a cherished pet and devastating effect a tragic medical error can have on the staff and the practice.

Product Focus

EMD Safety Valve

EMD Safety Valve
  • Manufacture

    Adapter bodies are custom CNC machined from billet aluminum and hard anodized

  • Specifications

    Valves open at approximately 26 cm H2O and can flow up to 4 liters/minute when fully open.

  • Quality

    Valves are manufactured at an ISO 9001:2008 certified facility of ABS plastic and use nitrile o-rings

  • Application

    Precision manufactured for an air-tight fit between the anesthetic machine and the Y tubes – either side. The female connection now incorporates an O-ring for better sealing.

Product Focus

EMD Scavenge Adapter

EMD Scavenge Adapter
  • WAG Safety

    This adapter plumbs the Safety Valve into the existing scavenge system preventing Waste Anesthetic Gas release when the valve is activated.

  • Sizing

    Tee adapter will accommodate 19 and 22 mm scavenge tubing.

EMD Safety Valve in use

Customer Feedback

Every machine should have one of these.

A well designed product

These should be standard on every anesthesia machine