Hi Dee, there's two terms mentioned here "tissue'ing" and extravasation.

I cannot find anything more about this term "tissue'ing" but I can find
lots about extravasation.

http://www.cancerhelp.org.uk/help/default.asp?page=302
Possible problems with a drip
Doctors often use central lines for chemotherapy because drips can be
temperamental.  They can stop and start when you move your arm.  And the
speed of the drips is not as easy to regulate as it is with a central
line connected to a pump.  But the most serious potential problem with a
drip is fluid leaking out into the surrounding tissues instead of going
into the vein.  Nurses usually call this 'tissue-ing'.  Generally, this
will cause the area to become hard, slightly swollen and sometimes red.
Often these problems are very minor.  The doctor or nurse resites your
drip and after a day or so the swollen area has completely recovered.

But some chemotherapy drugs can cause more damage if they leak.  These
are called vesicants.  Your doctor and nurse will be aware if the drug
you are having is a vesicant.  They may ask you to keep a close eye on
it and let them know as soon as possible if the drip stops going, or if
the area around the needle (cannula) is getting sore.  Our chemotherapy
drug pages say if a drug is a vesicant, so you can check for yourself if
you like.  Doctors and nurses sometimes call drug leakage
'extravasation'.  This just means 'out of the vein'.

If you are treated with a vesicant drug that leaks, it can cause pain
and ulceration to the body tissues.  This doesn't necessarily happen
straight away.  There may not seem to be much harm done.  But the area
can become more swollen and painful over the next few days.  Ulcers
(sores) may develop within 2 weeks.  This type of damage can take quite
a long time to heal.  " [end copied text from website)

I'll post (separately) what I have about  'extravasation'.
Also maybe it's time for you to tell us when this happened, the name of
the chemo(s), Whether anything was done immediately by the doctors or
nurses to help the situation and what reaction occurred (ie how is the
patient?) AND some of the other questions you have (if they're not
answered on some of the web sites that I'll post). I'm not a doctor nor
a nurse, so I'm not sure that I'll be able to answer any questions but
there are others here reading who might have input.
J

Hello Dee, hopefully something that I posted helped you.
If you do have questions, there are doctors reading this newsgroup.
J