Postoperative hypoxemia in the absence o fhypoventilation occurs more often after thoracic or upper abdominal surgery than lower abdominal operations or surgery on extremities. Although the factors which produce postoperative alveolar collapse
have
not
been fully evaluated, the dominant factor of postoperative hypoxemia is shunt of blood passing collapsed alveoli and the postoperative pain is associated ith restriction of depth of breathing, sighing and inovement.
In 1979, the first successful clinical usage of epidurally administered morphine for control of postoperative pain was reported by Behar and associates.
This study was carried out for twenty patients who received posterolateral thoracostomy with bleb resection between May 1990 and May 1991 and who were primary spontaneous recurrent pneumothoraxes under general endotracheal anesthesia. For the
relief of
postthoracotomy pain following of the general anesthesia, we selcted ten patients as control group which were treated intermittently IM with injection of pethidine (50mg) according to the conventional method and another ten patients as study
group
which
were managed with thoracic epidural analgesia. The tip of the catheter was inserted to T4-5 epidural space through T12-L1 or L1-2 interspinous region before the induction of the general anesthesia and then the epidural analgesics (0.25%
bupivacaine
15
ml+morphine 3 mg) was injected once a day via the cathetetr until 4 th day in study group.
Clinical observations were done about vital signs, ABG, tidal volume, FVC and occurrence of adverse effects during postoperative 2hr 8hr, lst day, 2nd day, 7th day in both groups.
@ES The results were as follows;
(1) The values of VT and FVC were significantly improved in study group (85% and 66%) as compared with control group (76% and 61%) during the postoperative 4 day of the epidural analgesia.
(2) After the end of the epidural analgesia (7th POD), the values of FVC were improved invertly rather in control group (98%) thean study group (84%). It suggested that the reduction of FVC in study group were caused by the raised pain
sensitivity
following the end of epidural analgesia.
(3) The side effects of epidural analgesia such as transient urinary retention (2 cases), itching sensation (1) and headache (1) were noted.
|