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**uberlad** · 5 December 2000, 09:09

You watched not only a Perfect Storm, but also mission to mars _and_ Erin Brokovitch (how many spellings can we get in one thread?)

No wonder you're feeling tired, listless and lacking the urge to revise.

I can't see Kevin and Perry being good either......

Watch good films. Although the FF8 idea is good.

Or try to see how strong you can make coffee and have it still liquid.......

Or just sit on a book and hope to absorb knowledge.......

Generally, come up with something better than revision and then revise as an alternative to that.

Or just post all over the forums.....

Uberlad, not wanting to work.

------------------
-------------------------
8 out of 10 women say they would feel no qualms about hitting a man.
5 out of 10 referred to me by name.

**Paddy** · 5 December 2000, 09:15

Actually the fear and panic are starting to set in.

God I love adrenaline!

Galaxy Quest did cheer me up though!

**Paddy** · 5 December 2000, 09:30

I think FF8 would take up too much of my time right now!

**ayoub_ibrahim** · 5 December 2000, 10:55

quoted from Paddy[MU]:"God I love adrenaline"
does that mean you'll like to have a phaeochromocytoma????

[This message has been edited by ayoub_ibrahim (edited 05 December 2000).]

**Paddy** · 5 December 2000, 11:12

<BODY>
<H2>No, it does not!</H2>

<H3>1) Incidence of phaeochromocytoma</H3>

Rare tumour which may present at any age, but usually 40-50;
female > male; 0.5% of all hypertensives. Only 10% occur in
childhood, in this age group phaeos are twice as common in boys than
girls, 20% are bilateral, and the tumour is more malignant.</P>

Occurs in Chromaffin tissue, usually abdominal, and 90% are
adrenal. Other sites include Coeliac, Renal, Hypogastric, Sympathetic
chain ganglia, and the organ of Zuckerkandl. 15% have metastatised at
the time of diagnosis (35% in kids and 8% in adults).</P>

<H3>2) Symptoms</H3>

Classic episodes of headache (hypertension), sweating, axiety,
pallor, and palpitation (arrythmias), provoked by posture, exercise,
anxiety, pain, and drugs, occur in only 50% of phaeos. Most of these
do not have elevated resting BP's; the others are found during
investigation of hypertension. Postural hypotension is common (70%)
in Phaeo's and suggests the diagnosis in an untreated hypertensive.
It should also be considered in pre-eclampsia, thyotoxicosis, and
malignant hypertension.</P>

<H3>3) Associated disesases</H3>

Medullary thyroid cancer, parathyroid adenoma, other neuromas. Von
Recklinghausens in 5% of Phaeo's, but Phaeo's seen in only 1% of Von
Recklinghausens. 5% inherited.</P>

<H3>4) Diagnosis</H3>

<H4>a) Urine</H4>

<TABLE BORDER=1>
<TR>
<TH>

24 hr metanephrine</P>
</TH>
<TH>

24 hr u.VMA</P>
</TH>
<TH>

24 hr u. Catecholamines</P>
</TH>
</TR>
<TR>
<TD>
<CENTER><2.0 uM/24 hr</CENTER>
</TD>
<TD>
<CENTER>< 20.0 uM/24 hr</CENTER>
</TD>
<TD>
<CENTER>< 0.5 uM/24 hr (100 ug/24 hr)</CENTER>
</TD>
</TR>
<TR>
<TD>
<CENTER>(<0.4 mg/24 hr)</CENTER>
</TD>
<TD>
<CENTER>(< 4.0 mg/24 hr)</CENTER>
</TD>
<TD>
<CENTER>(<100 ug/24 hr)</CENTER>
</TD>
</TR>
<TR>
<TD>
<CENTER>Best, most accurate</CENTER>
</TD>
<TD>
<CENTER>Misses 20%, false positives</CENTER>
</TD>
<TD>
<CENTER>Usually Normal</CENTER>
</TD>
</TR>
</TABLE>
</P>

<H4>b) Plasma catecholamines</H4>

Generally the most accurate, but owing to short half-life may get
false negatives if tumour hasn't recently been stimulated.
Significant Adrenaline production strongly implies adrenal
location.</P>

<TABLE BORDER=1>
<TR>
<TH>

Catechol</P>
</TH>
<TH>

normal</P>
</TH>
<TH>

hypertensive</P>
</TH>
</TR>
<TR>
<TD>
<CENTER>Noradrenaline</CENTER>
</TD>
<TD>
<CENTER>< 2.0 nM/l (< 300 pg/ml)</CENTER>
</TD>
<TD>
<CENTER>< 4.0 nM/l</CENTER>
</TD>
</TR>
<TR>
<TD>
<CENTER>Adrenaline</CENTER>
</TD>
<TD>
<CENTER>< 0.3 nM/l (< 50 pg/ml)</CENTER>
</TD>
<TD>
<CENTER>< 0.6 nM/l</CENTER>
</TD>
</TR>
</TABLE>
</P>

<H4>c) Provocation</H4>

Glucagon or histamine provocation of catechol release then blood
levels taken - little used these days.</P>

<H4>d) Suppression</H4>

Clonidine 300ug has no effect on plasma Nad in phaeo but
suppresses normal.</P>

 </P>

<H3>5) Tumour localisation</H3>

IVP: Positive in only 40%

Ultrasound: Positive in 85%

Angiography: Selective angio has risks of GA but localises 90% - DSA
bettter

Selective renal venography:

CT Scan: AS good as the selective angios, but may miss the smaller
phaeos

Scintiscan: Meta iodo benzyl guanidine 90% accuracy.</P>

 </P>

<H3>6) Preoperative drug management</H3>

<H4>a) Phenoxybenzamine:</H4>

Non competitive alpha-blocker, with long (24 hr) half life. Allows
plasma volume re-expansion, but some hypertension on handling may
still occur.</P>

Dose is 20 mg/day orally, increasing by 10-20mg/day, until desired
effect. Overdose causes toxic megacolon and postural hypotension.</P>

<H4>b) beta-Blockers</H4>

Added to manage persistent tachycardia, arrythmias, angina. May
worsen BP and LV performance unless adequately beta-blocked.</P>

<H4>c) Prazosin:</H4>

6-10mg of this alpha-1 selective blocker used with propranolol in
high doses (120-480 mg/day)</P>

<H4>d) Labetolol:</H4>

Has been decribed but is probably inadequate alone. Good for
resting rather than paroxysmal hypertension; frequently need Nad
postop.</P>

<H4>e) Magnesium:</H4>

MgSO> 2g IV may be useful for managing acute episodes.</P>

 </P>

<H3>7) Anaesthetic management</H3>

Aim is to avoid excessive sympathetic stimulation, hypoxia, and
hypercarbia, and to be able to cope with the acute changes (ie,
hypertension, arrythmias, etc) which may arise. Several weeks of
bedrest and preoperative drug treatment in hospital are usually
required.</P>

<H4>a) Assessment</H4>

Roizens criteria for adequate preoperative control are:</P>

Blood pressure < 165/90

Postural BP fall to not below 80/45

ECG free of ST changes for two weeks

< 1 VEB over 5 minutes</P>

Look for significant LV compromise or dysfunction, and consider
S-G catheterisation if present. Book an ICU bed postop. Check BSL,
K<SUP>+</SUP>. Crossmatch blood.</P>

<H4>b) Premedication</H4>

Relief of anxiety is important, deep premeds usually advocated.
Almost all drugs have been used without problems, however Droperidol
has been associated with some idiosyncratic responses, and Atropine
is often not recommended. alpha-blockers and other short acting drugs
are usually given on the same day, but not phenoxybenzamine.</P>

<H4>c) Choice of anaesthesia</H4>

Intubation and muscle relaxation is required for access, and
anaesthesia with volatile agents, narcotic, and neurolept techniques
have all been used. Gallamine, pancuronium, and suxamethonium have
disadvantages, and Halothane may worsen arrythmias. Agents that
release Histamine best avoided (morohine). Relaxant, nitrous,
narcotic, and Enflurane or Isoflurane supplementation are
recommended.</P>

<H4>d) Monitoring equipment</H4>

CVP (for monitoring and vasoactive infusions) and Arterial line
(essential).</P>

Swan-Ganz if LV dysfunction or other indications present.</P>

Usual equipment for a long case with bloodloss, ie ECG, IV,
warming blanket, blood warmer, humidifier, temperature probe, HiLo
cuffed ETT with pressure monitor, NGT, Urinary catheter, etc.</P>

<H4>e) Induction</H4>

Major danger period, requiring profound reflex supression prior to
intubation. Insert arterial line prior to induction and ensure an
adequate CVP. Avoid Ketamine; use a large dose of thiopentone, +/-
Fentanyl, Diazepam, IV or topical lignocaine, MgSO4 etc.</P>

<H4>f) Hypertensive crises</H4>

Provoked by noxious stimuli or tumour palpation, usually best
managed by removing the stimulus. SNP bolus, Phentolamine 1-5 mg IV
bolus or by infusion, MgSO4 2g IV, Lignocaine 1-2 mg/kg, Propranolol,
etc are all useful.</P>

<H4>g) Postoperative hypotension</H4>

Very common, due to combination of residual alpha and beta
blockade, fall in circulating catecholamine levels, receptor
downgrading, and diminished blood volume. 50% have significant
hypotension for 3 days.</P>

Management requires good pain relief, adequate fluid load, IV
infusions of catecholamines, ICU observation and monitoring. Always
be wary of an Addisonian crisis.</P>

 </P>

<H3>8) Phaeochromocytoma in pregnancy</H3>

25-50% mortality if untreated in 1967; tumour excision
mid-pregnancy or simultaneous Caesarian Section and excision have
been advocated, although several cases of successful epidural C.S.
and vaginal delivery with later excision have been described.</P>

<HR>

</P>
</BODY>
</HTML>

**Paddy** · 5 December 2000, 11:16

Excuse bad formatting!

(cut and paste)

**ayoub_ibrahim** · 5 December 2000, 13:30

see how much revision you can get done in this forum Paddy! pity its not a general medical exam tomorrow as hypertension & its causes is considered bread & butter stuff for undergrad exams.
best of luck tomorrow my friend!

**Paddy** · 5 December 2000, 14:52

I am sure it will be fine!

They wont want to throw me out at this stage (I hope!)

Cheers for the support!

btw: What is it you do again (after all, i'm the 'bogus paramedic' - remember?)

**SteveC** · 8 December 2000, 17:23

So, Patrick, how'd it go?

------------------
Cheers,
Steve

"Life is what we make of it, yet most of us just fake"

**Paddy** · 10 December 2000, 03:29

Not sure, I have passed all so far...
Final result comes out on monday.

I have clocked up 20hrs+ on FF8 though!

Thanks for asking!

**paulcs** · 10 December 2000, 07:51

Patrick, no one answered your first question, so let me take a shot at it.

Pre-med is the undergraduate phase. Regular old college with a major in medicine.

Then there's medical school.

After med school, there's the long, unpleasant, medieval internship.

Once that's over, you're required to learn golf.

Paul
paulcs@flashcom.net

**Paddy** · 10 December 2000, 10:51

How long is the undergraduate phase?

**Paddy** · 10 December 2000, 10:55

In the UK:

You do a medical degree, which lasts 5 years followed by 6mths post-med training.

The 5 year long degree is split into pre-clinical (which i have just finished) and clinical, each is 2 1/2 years.

At the end of it all, I come away with two degrees:

MB (bachelor of medicine)
ChB (bachelor of surgery)

---
Cheers for the info paul

**paulcs** · 10 December 2000, 12:22

The undergraduate phase is typically four years. It's a bachelor's degree program with an emphasis on the life sciences. Medical schools are very competitive, so you have to get very good grades, do well in the "weeding out" courses (biochemistry, some nasty math courses), and then, do well on a nasty standardized test (MCAT?).

You don't have to graduate from a pre-med program to get into medical school, however. They all seem to require certain undergraduate courses, but I know people who got into medical school with liberal arts degrees.

I think medical school training lasts for two or three years. Once you graduate from med school, you're expected to do an extended internship at a teaching hospital. This provides "on the job" training, although there is an almost bizarre emphasis on endurance. Eighteen hour shifts are common. Pay is low. Status is low. Stress is very high.

I once visited a doctor friend at a hospital. Whenever an intern passed by, he peppered them with questions. So there is also a big emphasis on drill.

The eighteen hour shifts are somewhat controversial, because interns are responsible for a sizable percentage of diagnosis and treatment when patients first enter the hospital. There are questions about the quality of care towards the end of those eighteen hour shifts.

(Coffee shops near medical schools/university hospitals in San Francisco appear to be open twenty-four hours a day.)

The internship, I believe, is actually optional, although I don't think you're allowed to treat patients without it. If you forgo the internship, I guess you could go on to become a hospital administrator or researcher.

I wasn't a med student, so I'm relying on my memories of what my friends went through.

Paul
paulcs@flashcom.net

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Nothing in here, just a rant - i wouldn't bother

Nothing in here, just a rant - i wouldn't bother

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