Every year, about 1,800 people in Singapore collapse from out-of-hospital cardiac arrest. If cardiac arrest goes untreated for more than four minutes, brain injury is likely to happen as blood and oxygen circulation in the body stops.
To improve survival rate and prevent brain injury, paramedics will usually give the victim a dose of a life-saving drug, adrenaline through an intravenous (IV) line inserted into a vein as it could help restore blood flow to the heart. Unfortunately, placing the IV line within the first minutes is difficult because the veins are collapsed during a cardiac arrest due to the lack of blood circulation. Every second delay is a difference between life and death.
The Singapore General Hospital (SGH) and Singapore Civil Defence Force (SCDF) will be evaluating another method of injecting adrenaline via Intraosseous (IO) infusion. It is the process of getting entry directly into the marrow of a bone. Paramedics will use a powered medical drill to insert an Intraosseous catheter into an area beneath the knee joint for infusion. It is rapid, safe and acts as a suitable alternative for IV access. Pre-hospital Intraosseous insertion is used in some countries with good results.
“Giving adrenaline to restore blood flow to patient’s heart as early as possible is important but placing an IV line can be challenging in cardiac arrest. In addition, some patients who are obese, diabetic or on renal dialysis, often have narrowing or blockage of the blood vessels. Paramedics are also affected by factors like poor lighting or space constraints such as in the case of a car crash,” said Dr Kenneth Tan, Associate Consultant, Department of Emergency Medicine, SGH and lead investigator of the study.
Starting July 2014, the evaluation, which will involve 400 out-of-hospital cardiac arrest patients over a one-year period, will compare conventional IV line versus Intraosseous access in the treatment of cardiac arrest victims. During the evaluation period, a fleet of SCDF ambulances will be equipped with the powered medical drill and IO needles. The paramedics have been trained since September 2013 by the doctors from SGH’s Department of Emergency Medicine on how to use the device. Infusion by IV access will still be the first choice of treatment and Intraosseous infusion will only be given when paramedics are unsuccessful in placing an IV line.
“The evaluation findings have the potential to change the current out-of-hospital cardiac arrest protocols, equipping SCDF paramedics with an additional medical procedure that they can use to enhance cardiac arrest treatment. This can further raise the standard of pre-hospital care given to such patients,” said COL (Dr) Ng Yih Yng, Chief Medical Officer, SCDF.
Intraosseous insertion has been an accepted standard of care in SGH for critically ill patients where it is impossible to get obtain rapid IV access. It is also used in pre-hospital care in some countries such as Australia and United States with good results.