Phaco Training: Vaso-Vagal attacks during retinal lasers

By | September 3, 2014

Here I wish to discuss something uncommon, but very serious

 retinal photocoagulation (PRP, focal and barrage) is generally a very safe procedure as it is non invasive  

But many of us would have come across occasional cases of young people collapsing during the procedure

Several retinal surgeons of India have given their opinion regarding their experience and views on its management:


1. Vasovagal attack is very common during laser for young boys in their teens. (Almost every second  boy treated with barrage laser in my experience). Almost all recover within a couple of minutes after making them lie down.

It may be due to the fast repetitive flashes of the visible laser beam (more likely) or the pain.

It may not happen with red diode laser.

Members using red diode laser can give some inputs.


I had also experienced patients going in vasovagal attack following laser. First they complain of feeling hot then they start sweatingfeeling of nausea ,vomiting and even breathlessness.followed by syncope.

In all the patients symptoms were relieved by keeping head low and giving them drinking water.

I think we should take extra precautions in the patients who complain of excessive pain during laser.


In fact if the patient is not complaining and is extra cooperative we must suspect something is wrong especially in a young man. I ve had patients who become very still during laser. I immediately stop and question them and when they dont respond, immediately make them lie down on the floor and lift their legs.

Laser can also lead to devastating complications and we should be prepared for all the eventualities. I think Im the only unfortunate person of this group who has seen 2 deaths after laser.
1st case was an old diabetic both eye add prp done by a junior fellow in our institute. After laser was pt started coughing and sister ran to me. I saw and realised it is an MI. Pt was sifted ICU , CPR , intubation and then shifted to cardiac hospital . He died after 2 days of treatment in iccu.
2nd case was lasered by me in my private practice. 80 year old diabetic during laser became breathless . I called a physician besides my clinic. He diagnosed MI. After doing primary management we called the ambulance and send him to cardiac hospital . On the way he felt better he got out of ambulance to urinate and he got reMI. Finally he died before reaching the hospital.
I just shared this experience so that we expect even worse in simple procedures also and we should have at least all emergency drugs available in our clinic. Old age diabetics are especially prone to have silent.


Great discussion .Agree with all. Would add just 2 things –

(a). While vasovagal attack is very frequent in young teens (typically undergoing barrage laser). It is extremely uncommon during second sitting in same patient. So, anxiety does lower the threshold. We ask these patients to keep flapping their feet and keep closing and opening the fist during the procedure. This helps in 2 ways, pumps the stagnant venous blood back towards the brain and also distracts them!.

(b). Once, it develops, it helps to raise the legs for faster recovery. Also, avoid offering water. It is pseudo- thirst & disappearance of this thirst actually signals recovery. Water given orally might interfere with resuscitation if required. Also, let our assistants be aware of this and they should be ready to catch/support these patients to prevent any head Injury.

Only way to be prepared for rare events like MI case is to conduct mock drill for systems preparedness.


well its not the LASER that has caused devastating complication per sewe are already treating patients with debilitating diseases..and are at risk for cardiac or cerebro-vascular events..its important to be aware to take the required precautions and upgrade of response skill in the event of an emergency..its difficult to face these situations in our practice..we need to be geared up for it..and train our staff too to respond in these situations.

that was the very aim of posting this caseto revise our emergency medicine..


I am uploading a beautiful case presentation made by one of the retinal surgeons.

It describes a case of vaso-vagal attack in his practice as it happened:

vasovagal attack 17-8-14



 Boarding a sea plane at Juneau, Alaska