She was making out a receipt to a customer when she saw a man collapse outside the bicycle shop.
Miss Jeannie Toh, 25, who works at the Mighty Velo shop in Lavender Street, quickly called the Singapore Civil Defence Force (SCDF) and shouted for her colleague to alert her boss.
The incident happened at around 4.50pm on March 12.
She picked up a calendar and rushed out to check on the man, who seemed to be in his 50s.
She said: "I saw his eyes turning blood-shot and he wasn't blinking. I tried to fan him with the calendar.
"His breathing was shallow, and I called out 'Uncle, Uncle', but he didn't respond."
Miss Toh had attended a one-day cardiopulmonary resuscitation (CPR) course about seven years ago when she was a combat signaller in the Singapore Armed Forces.
She took the man's pulse by feeling the area on his neck near the chin with two fingers.
"I didn't feel any pulse. But I didn't know if it was because he had no pulse or because I was shivering," she said.
SCDF Sergeant Ramli Selamat, 31, was the one who picked up her call. He asked her to describe the situation and despatched an ambulance immediately.
He asked to hear the man's breathing over the phone, so Miss Toh put the phone on speaker mode and held it against the man's mouth.
From her account and from the man's shallow breathing, Sergeant Ramli assessed that the man was having a heart attack.
Miss Toh said: "He told me that I would have to perform CPR because the uncle might not be able to wait for the ambulance. He said that he would guide me over the phone."
She hesitated at the thought of having to perform mouth-to-mouth on a total stranger, but was reassured by Sergeant Ramli that all she needed to do was to perform chest compressions on the man.
In her words, this was how the conversation went:
Sergeant Ramli: Ma'am, you need to put your hands with your fingers placed on top of his chest.
Miss Toh: Okay.
Although he didn't tell her where to put them, she roughly knew the position from her previous CPR training.
Sergeant Ramli: Now you need to do 100 counts of compressions.
Miss Toh: 100 counts?
Sergeant: Ramli: Yes. Are you ready? You need to push down as hard as possible. We'll count together.
Miss Toh: All right.
Sergeant Ramli and Miss Toh: one and two and three and... 10
Sergeant Ramli and Miss Toh: one and two and three and... 20
Sergeant Ramli and Miss Toh: one and two and three and... 30
While all this was going on at the walkway in front of the shop, Miss Toh's colleague, Mr Tommy Lam, 39, ran across the road to the Boon Keng Fire Post to alert the SCDF officers on duty.
Her other colleagues and boss stood nearby and helped to direct customers and passers-by away.
Miss Toh completed 30 chest compressions on the man before two SCDF officers arrived and took over. They continued performing CPR and used an Automated External Defibrillator (AED) to try to revive his pulse.
Miss Toh, who was still in a daze from the frenzied activity, was pulled aside by her boss.
An ambulance arrived and took the man to Tan Tock Seng Hospital (TTSH) after paramedics managed to revive his pulse.
Said Miss Toh: "During the whole incident, my mind was a blank. All I could see was the uncle and all I could hear was the officer on the phone. Everything else was a blur."
After the ambulance left, Miss Toh broke down.
"I saw the blood going into his eyes. I really wasn't sure if he would make it then. What if my actions didn't help him? What if (they actually) killed him?
"I was in shock when they were shocking him with the AED machine," she said, adding that although her actions lasted less than 10 minutes, it felt like forever.
"I never took my CPR training seriously until that day. It's like the Chinese saying, you train hard all your life just for that one performance."
Her boss, Madam Vivian Yuan, 44, said she now hopes that all her employees can undergo CPR training.
She said: "You never know when you need to administer CPR. With such skills, you can help to save lives."
SCDF's Chief Medical Officer, Lieutenant Colonel (Dr) Ng Yih Yng, said: "Every second counts in a cardiac arrest case. A bystander stepping forward to perform CPR will greatly increase the chances of survival for the patient.
"Even if you do not know CPR, our 995 call-takers can help coach you to start chest compressions, and use an AED if it is available." The man is now in the Intensive Care Unit at TTSH. His condition is unknown.
For their valiant efforts, Miss Toh and Mr Lam were given the public spiritedness award by the SCDF.
WHERE TO LEARN CPR
Sergeant Ramli Selamat, the Singapore Civil Defence Force officer who guided Miss Jeannie Toh over the phone, is often called to "do" CPR over the phone.
He receives calls requiring him to guide callers at least once or twice each time he is on duty.
He said: "Usually, the calls come from family members who would perform CPR on their family.
"Very rarely is it members of the public, like in this incident."
You can learn basic CPR skills and First Aid at various institutions.
The Singapore Red Cross Academy
Sign up at www.redcross.org.sg or call 6664-0500 ext 564/565 for more information.
St. John Ambulance Singapore
Sign up at www.sjas.org.sg or call 6298-0300.
Singapore Heart Foundation
Sign up at www.myheart.org.sg or call 6354-9340.
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