Heart attack deaths ‘may be due to emergency response times’

UCC study finds ‘lengthy’ waits for help may contribute to low survival rates among the elderly

 UCC researchers say the survival rate for older people who suffer cardiac arrest in the community and receive emergency treatment and resuscitation is under 3%. File photograph: Alan Betson

UCC researchers say the survival rate for older people who suffer cardiac arrest in the community and receive emergency treatment and resuscitation is under 3%. File photograph: Alan Betson

 

Ireland’s high rural population and lengthy emergency response times may be contributing to lower survival rates among older people who suffer heart attacks, according to a new study.

The survival rate for older people who suffer cardiac arrest in the community and receive emergency treatment and resuscitation is under 3 per cent, it says.

This 2.9 per cent survival rate for over-70s with an out-of-hospital cardiac arrest is less than half that for the general population, the study published in the BMJ Emergency Medicine Journal finds.

This compares to survival rates for older people of 12 per cent in The Netherlands and 6.7 per cent in Sweden.

The report led by researchers in UCC says our high rural population and “protracted” emergency response times may be factors contributing to Ireland’s lower survival rates. Each minute without cardiopulmonary resuscitation (CPR) and defibrillation reduces the chance of survival by 7-10 per cent.

In only one-in-four heart attacks examined by the researchers were emergency medical staff on the scene within eight minutes of being requested.

“Delayed defibrillation is likely if emergency medical services are not present and robust community first-responder programmes are not in place.”

Cardiac arrest

Over half of the cases had asystole (flat-line), the most serious and irreversible form of cardiac arrest. The study suggests this “bleak prognosis” may be due to delays in defibrillating the patient.

The older people suffering heart attacks were most likely to be in a residential institution. Yet in more than 20 per cent of cases, no CPR was applied before emergency staff arrived. The study says this figure is high, considering these homes are staffed by trained personnel.

“This may represent an uncertainty among staff as to whether it was appropriate to start CPR on an elderly patient.”

The researchers point to studies that suggest “medical futility” applies where therapies have less than a 1-5 per cent chance of a successful outcome.

The study looked at almost 2,300 patients aged 70 years and older who were attended by emergency medical services and had resuscitation attempted in Ireland between 2012 and 2014.

Overall survival rate to hospital discharge was 4 per cent for those in their 70s, 1.8 per cent for patients in their 80s and 1.4 per cent for those 90 years and older.

A bystander witnessed the heart attack, and CPR was performed, in about six out of every 10 cases. However, CPR performed by the bystander was associated with a reduced chance of survival.

Use of defibrillators

The biggest contribution to survival was made by the presence of a shockable rhythm. Where this was present in the person having the heart attack, the survival rate was 12.9 per cent. In its absence, this fell to just 0.4 per cent.

The authors say the strategic placement of defibrillators in areas with an older age profile may increase their use and reduce the time to first defibrillation.

Community first-responders could be an integral part of the chain of survival, but programmes are not widely available in Ireland, they add.

The authors acknowledge that resuscitation may not be appropriate for every heart attack case, may be distressing for families and may undermine the care of a dying patient.