Portable Medical Ventilators for Hospitals and Ambulance Services

Medical ventilators support breathing when a patient cannot breathe adequately without assistance. They are used in emergencies, intensive care and other settings where respiratory support is needed, sometimes for an extended period. Mechanical ventilation helps move air into the lungs; oxygen therapy supplies additional oxygen and does not necessarily provide that breathing support. The NHLBI overview of respiratory failure treatment distinguishes these approaches.

Older equipment was often bulky and expensive, which limited portability and access. Compact devices now make ventilation possible during ambulance journeys and transfers within hospitals. A portable unit still needs to be approved for its intended environment and the patient’s requirements; size alone does not make it suitable for every transport or ward.

How to choose a ventilator

A transport ventilator can provide essential respiratory support when used by trained healthcare professionals. Patient assessment, appropriate airway management and equipment checks come before connection. Ventilation can also form part of an anaesthetic system, but a transport ventilator and an anaesthesia workstation are not automatically interchangeable or compatible.

A simplified age grouping used in the original article is:

• Neonatal transport ventilators. These serve the smallest patients; neonatal intensive care also uses ventilators designed for babies with serious respiratory problems.
• Devices for children under six years old.
• Devices for patients aged six years and over.

These age bands are not universal device specifications. Select equipment by the manufacturer’s approved patient groups, weight ranges, required ventilation capabilities and compatible circuits. Some devices cover neonates, children and adults, with the appropriate options and accessories. For example, Hamilton Medical describes the HAMILTON-T1’s transport capabilities and identifies optional functions. Changing a mask alone does not make a device suitable for a different patient group.

Design and operating characteristics

A ventilator has a gas-delivery system, a gas supply or air-generating mechanism, controls and monitoring displays. Their layout varies: measurements and controls may share a screen rather than occupy separate panels. Review the actual specification, including which values are measured and which are merely set by the operator. Important parameters include:

• Tidal volume: the volume associated with an individual breath.
• Respiratory rate: the number of breaths per minute.
• Minute ventilation: the volume ventilated in one minute.

Ventilation modes describe how breaths are delivered and supported. They can include mandatory breaths delivered according to programmed parameters, support for breaths initiated by the patient, and approaches that combine mandatory and spontaneous breathing. Exact mode names and functions differ by device.

A resuscitation bag, a face mask and an endotracheal tube describe equipment or ways of delivering ventilation, rather than interchangeable names for ventilator modes. Bag-mask ventilation is a separate technique; ventilators may provide non-invasive support through a suitable mask or invasive support through an airway tube, within their approved use. Clinical staff select the approach and settings for the individual patient.

Why the device matters

Ventilation can be lifesaving by supporting oxygen delivery and carbon dioxide removal when breathing is inadequate. It is used by emergency teams and in medical centres. It does not guarantee normal gas exchange or prevent every complication, and it must accompany treatment of the underlying problem and continuing patient assessment.

Before transport, check alarms, the breathing circuit, gas supply, battery charge and a suitable backup plan. Power and oxygen availability can limit operation. The NHS Greater Glasgow and Clyde HAMILTON-T1 transport guide illustrates pre-use checks and separate patient monitoring for that service; its local arrangements are not specifications for every ventilator.

Some devices have built-in filters or accept compatible filters. Their purpose and placement must follow the manufacturer’s instructions. Filters should never be assumed to make ventilation safe in environments affected by:

• Radiological contamination.
• Chemical contamination.
• Biological contamination.

Particle filtration does not shield against ionising radiation or remove every gas and vapour. A breathing-circuit filter is not a general CBRN protection system. NIOSH guidance on CBRN respiratory protection describes hazard-specific equipment and restrictions. Care in contaminated areas requires an appropriate incident response, safe gas supply and protection for personnel as well as the patient.

The original article suggests one broadly suitable ventilator for routine ambulance use and additional units for disasters or major accidents. Equipment numbers should instead reflect the service’s patient groups, workload, backup arrangements and major-incident plan; interchangeable masks do not resolve those planning requirements.

When purchasing, check the device’s required market authorisation or registration, instructions, maintenance arrangements and service history. Documentation and a warranty do not guarantee that equipment can never fail. Dependability also requires trained staff, routine checks, maintenance, reliable consumables and contingency equipment.

Source: Zaplata: portable medical ventilators for hospitals and ambulance services.