Læknaneminn - 01.10.1996, Blaðsíða 109

Rannsóknarverkefni 4. árs læknanema, útdrættir
ple in cerebral infarction and head trauma is a glycolytic
enzyme, Neuron-specific Enolase (NSE). This prospective
study focuses on the postoperative NSE serum level in pati-
ents undergoing carotid endarterectomy (group 1) and pati-
ents undergoing uncomplicated major general surgery
(group2). During carotid endarterctomy, the blood flow
through the artery is interrupted for about half an hour and
the ipsilateral part of the brain is therefore at risk of hypop-
erfusion. Stroke occurs in 1-7% of the patients after the
operation but less severe neuronal damage, presenting as
cognitive deficits, may be more common. Our hypothesis
was that the serum level of NSE would increase after carotid
endarterectomy. If an increase could be detected, we would
correlate the increase with the postoperative cognitive def-
icits.
Methods and materials: Group 1 consisted of 11 pati-
ents, with a median age of 61 years (range: 52-/2) and group
2 consisted of 35 patients. Blood samples were drawn from
the patients in the two groups before surgery and 12, 24, 36
and 48 hours after surgery, The NSE serum-level was mea-
sured with immuno-fluorometry and we calculated the
change in NSE by subtracting the preoperative value. Ne-
uropsycological testing was carried out by trained personnel,
using a test battery consisting of 6 subtest. The patients were
tested preoperatively and after surgery; the interval between
the operation and the second test was 4 days (median value,
range 3-6). To evaluate the difference in the patient's ne-
uropsychological performance after operation, the difference
between the first and second test session was calculated for
each subtest. These differences were classified as deficits if
they exceeded a limit calculated from a normative material of
elderly persons. This limit corresponds to a deterioration in
test performance encountered in less than 5% of normal sub-
jects.
Results: In group 1, two patients (18%, 95% confidence
interval: 0-41%) suffered from stroke as a complication aft-
er the operation. In one patient, the stroke was apparent
when the patient woke up after anaesthesia and by ultra-
sound examination it was found that the artery, that was
operated upon, was to be occluded. In the other patient, the
stroke occurred 36 hours after the operation. By CT-scan, a
cerebral infarct contralateral to the side of operation was di-
agnosed. The former patient had an almost 3-fold rise in
NSE, while the second had no increase. In the patients with
an uncomplicated carotid endarterectomy, we found a decr-
eae in NSE 24 hours after the operation. This decrease in
NSE was statistically significant when comparing with group
2 (p=0.028).
Of the 9 carotid patients tested postoperatively, neurop-
sychological deficits were seen in 4: One had 2 deficits and
three had 1. In two of these patients, the NSE level increa-
sed 36 hours after surgery. In contrast, the NSE level did not
increase in the patients with no neuropsychological deficits.
Discussion: We expected that the NSE-level would incr-
ease after carotid endarterectomy, Actually, we found a decr-
ease after 24 hours. This may be explained by volume load-
ing during anaesthesia leading to dilution of the NSE in the
blood. Another explanation may be that these patients ex-
perienced embolism of microthrombi from the plaque in the
artery, embolism that damage braincells leading to an el-
evated baseline value. After surgery, the incidence of such
embolism would decrease and hence, the outflow of NSE
from ischaemic neurones would decrease also.
The possible conncection between NSE increase in some
patients after 36 hours and the postoperative neurop-
sychological deficits is an issue that will be studied in a larg-
er number of patients by our group in near future.
Sýklalyjaónæmi hjá viridans streptókokkum
og tengsl þess við sýklalyfjanotkun hjá
íslenskum börnum
lónas Logi Franklín1.
Ásgeir Haraldsson2, Þórólfur Guðnason2,
Karl G. Kristinsson3.
’LHI, 3Barnaspítali Hringsins,
■'Sýklafrteðideild Landspítalans.
Inngangur: Sýklalyfjaónæmi hefur farið hratt vaxandi
undanfarin ár og hafa menn ekki getað haldið sama hraða í
þróun nýrra sýklalyfja. Sumir hafa spáð því að gullöld sýkla-
lyfjanna sé nú á enda. Árið 1989 barst hingað til lands fjöl-
ónæmur stofn S. pneumoniae og náði hann hér fljótt fótfestu.
Sýnt hefur verið fram á tengsl sýklalyfjanotkunar og tíðni
þessa ónæma stofns.
Viridans streptókokkar teljast til meinlausari baktería og
hafa því lítið verið rannsakaðir. Þeir eru hluti af eðlilegri háls-
flóru og eru þvít gott líkan til að meta hvernig bakteríur
bregðast við sýklalyfjum í umhverfi sínu. Tilgangur rann-
sóknarinnar var því að fá upplýsingar um sýklalyfjanotkun ís-
lenskra þarna og slcoða hvernig viridans streptókoldtar hafa
brugðist við henni-
Efixi og aðferðir; Ollum börnum er lögðust inn á Barna-
spítala Hringsins á 3ja vikna tímabili var boðið að vera með í
rannsókninni. Ymsar upplýsingar er lúta að heilsufari og
sýklalyfjanotkun barnsins voru skráðar og hálsstrok tekið hjá
þeim er tóku þátt, Hálsstrokinu var sáð á blóðagar og rækt-
að yfir nótt, Síðan voru þær þyrpingar á skálinni er líktust
viridans streptókokkum, skoðaðar í stækkun og þyrpingum
með mismunandi útlit sáð á blóðagar með optochin. Þeir
stofnar sem reyndust optochin neikvæðir voru taldir vera viri-
dans streptókokkar.
Næmispróf voru gerð á öllum stofnum samkvæmt aðferð
Kirby og Bauer. Prófað var næmi fyrir cephalothin,
chloramphenicol, erythromycin, oxacillin, penicillin, tetracy-
cline og trimetoprim-sulfamethoxazole.
LÆKNANEMINN
99
2. tbl. 1996, 49. árg.