Chill in the Air
Fall is here and winter is just around the corner. In the northern latitudes the temperatures after sunset are dropping and approaching the freezing level despite the somewhat warm and sunny daytime temperatures.
Prepare.
Cold weather presents significant challenges to patient transports on the most basic level. Despite detailed planning and coordination of operations including considerations of supplies, time factors and medical interventions, something as simple as freezing temperatures can adversely affect and increase the risk of injury or even death to the patient for what otherwise would be a routine transport in warm weather conditions.
Medical devices like syringe pumps, point of care laboratory devices, ventilators, intra-aortic balloon pumps, cardiac assist and other extracorporeal devices are not developed with the austere environment in mind. These devices are researched and advanced with “in hospital” bedside usage as the endpoint and transport remains a sidebar and not a primary consideration. There are exceptions: some devices are specifically intended for transport purposes though these improvements tend to focus on weight considerations and battery life and not its ability to withstand extreme temperatures for any period of time.
In bitterly cold temperatures, exposed IV lines can freeze in a matter of minutes. Humidity in ventilator circuits can freeze quickly damaging the fragile exhalation valves and tubing. Point of care (POC) laboratory devices routinely fail to perform in cold temperatures and exposed tubing on any support device can freeze and crack with devastating results for patient stability.
Transport “Despite” Austere Conditions…
All of this is worrisome and concerning and yet transports still take place routinely with transfers occurring in freezing conditions with most of our efforts leaning towards our primary objective of patient comfort and warmth. Overall, experience has shown that we do a good job of covering our patients and providing methods to warm and heat the transport environment as quickly as possible for our patients, but fail to consider exposed lines and critical, sensitive equipment.
There are however some simple and effective modifications that can be put into play to help alleviate some of the potentially disastrous effects of freezing temperatures within the transport environment.
Consider first the logistics of transport routes into and out of the referring hospital. Minimize the time outside of the buildings by discussing the shortest possible route to and from the transport vehicle. If an ambulance is the transport mode, ensure that the vehicle is running and pre-warmed before leaving the bedside with the patient. If you are transporting by rotor-wing or fixed-wing request enough help to quickly and efficiently load the patient and equipment with minimal time “out-side” for both the patient and the equipment. This should include loading / unloading patients in a hangar rather than on the tarmac if possible.
Complex and sensitive monitoring and therapy delivering equipment can be covered with light weight blankets for short periods of time without concerns for overheating of the circuitry. Leaving monitors and ventilators secured to a stretcher and exposed to freezing temperatures can damage that equipment but more importantly it could render that equipment ineffective for its purpose while caring for your patient.
IV pumps and IV bags can (for the most part) be tucked under blankets briefly without disrupting the flow of critical infusions. IV tubing can be wrapped around a heating pack to prevent freezing and insure the flow of those mediations. Any and all exposed lines should be covered with either blankets or commercially available coverings to prevent near immediate freezing or damage from extreme weather. Prime the entire fluid space and attach a pressure bag if not using gravity for fluid administration.
A general rule is that if you would cover a piece of equipment up in a rain shower to prevent it from getting wet, you should use equal caution in adequately covering that equipment when exposing it to extreme cold during transport.
Final Thoughts…
There are a multitude of variables and considerations that must be considered when addressing something as basic as the cold and its effects on our patients and equipment. Transporting patients from accident scenes has its own set of challenges and concerns, and this piece is not intended to try and answer those specific challenges nor any of the other possible variables given the differences in transport vehicles, configurations, teams and locals.
However, some simple pre-planning and thoughtful consideration of something as simple as the temperature outdoors and the possible effects that it might have on your transport equipment, not to mention your patients (if the equipment fails) is worth pondering.