Trekkers should be aware that there is very little in the way of rescue organization for handling trekker's emergencies in Nepal. If you are trekking with a reputable trekking agency then their staff will be trained to handle most contingencies. If you are traveling independently then you will have to rely on your own initiative to handle any problems. This is why trekking alone is foolhardy in the extreme.
At all times try to be aware of the location of possible sources of help, medical clinics, police or army posts etc. Try to find out where there are working telephones or radios as you pass along the trails.
All trekkers should make sure that they are covered by a suitable travel insurance policy. This, at least, must cover the cost of a helicopter rescue, which is the only practical way of evacuating a seriously ill or injured patient from most of the trekking areas. It is essential to leave details of this policy with a responsible agency in Kathmandu. Either your trekking agency or your embassies are the obvious choices. Registering your details and intended plans with your embassy in Kathmandu is an extremely sensible step to take.
In the event that you do have a problem, and that problem cannot be solved with the resources at hand, then communications facilities must be located. Telephones or radios can be hard to find and may be a day or more away from the incident site. If it is possible to send a reliable person for help make sure that a note is sent detailing the location of the patient, the problem being experienced, specifying what help is needed. List what actions you are going to take in the interim. Fortunately, these days, helicopters are readily available, at a price, from Kathmandu and Pokhara. If a message can be sent then it is likely that a rescue can be mounted reasonably quickly.