Hans Bolander

Retrospective analysis of 162 consecutive cases of ruptured intracranial aneurysms. Total mortality and early surgery

SummaryA retrospective analysis of 162 consecutive cases with ruptured intracranial aneurysm treated during the years 1979–1981 is presented. Total mortality was 33 %. Eighty-four patients were in Botterell grades I–II and 62 were operated with a direct attack on the aneurysm. Thirty-eight were operated early with a mortality of 5% compared with 13% for those operated late. There was no difference in morbidity between the two groups. Of the patients operated with clipping, 66% made a “complete recovery” and 21% were classified as independent.Signs of delayed ischaemia were recorded in 42% of patients operated early as compared with 25% in the late surgery group. The frequency of rebleedings in the total material was 15%. Hospitalization time was significantly reduced in the early operated group. The importance of analysing the total management mortality and morbidity for evaluation and comparison between early and delayed surgery is discussed.

Treatment of spontaneous intracerebral haemorrhage. A retrospective analysis of 74 consecutive cases with special reference to computertomographic data

SummaryThe surgical treatment of spontaneous intracerebral haemorrhage (SIH) is still a matter of controversy, although most Neurosurgeons agree that surgery is indicated in selected cases. The introduction of computer tomography (CT) permits a more accurate determination of the localization, size and expansion of an intracerebral haemorrhage. The aim of this study is to evaluate the results of surgical and conservative therapy in selected cases and to search for parameters that could help to predict the outcome and facilitate the decision between surgery and conservative therapy.Seventy-four patients treated following SIH during the years 1976–1980 were analyzed. The decision for surgical treatment was made on the basis of the patients conditions and the findings in the CT scan. Thirty-nine patients with mainly medium-sized haemorrhages underwent surgery and 35 were conservatively treated. The mortality after three months was 5/39 (13%) in the surgical and 7/35 (20%) in the conservative group. The volume of haemorrhage was significantly larger in the patients who died and 9/10 patients with a haematoma volume above 80 ml died. Five of these 10 were operated and the other 5 not and surgery seemed to be of little benefit to this group. Dilatation of the contralateral ventricle is another indicator of a bad prognosis.Long-term follow-up investigation was carried out 4–38 months after the initial treatment. Total mortality was 19 out of 68 patients that could be reached for late follow-up. Eleven patients (29%) were fully recovered and 16 had minor neurological deficits. There was no difference in late results between the surgical and the conservative groups, but the patients in the surgical group were generally in a worse condition and had larger haemorrhages that the others. The fact that the total mortality in this material is lower than in other conservatively treated series favours surgery in selected cases of SIH. The use of CT gives valuable information as to the prognosis and especially the volume of haemorrhage seems to be a good prognostic factor.

Morphine concentrations in serum, brain and cerebrospinal fluid in the rat after intravenous administration of a single dose

Morphine has been determined in serum, cerebrospinal fluid (c.s.f.) and in five brain regions in the rat after a single intravenous dose, using high performance liquid chromatography with an electrochemical detector. In pure solution 50 pg morphine and 200 pg naloxone could be detected. Maximal concentrations of morphine were observed in serum and in most brain regions 5 min after administration of morphine. There was a rapid decline in morphine concentrations during the first 30 min, in serum and in all brain regions studied. The morphine concentration in the c.s.f. was constant for the first 30 min, but 30 min later there was a dramatic increase, suggesting that elimination through the c.s.f. could be an important way of eliminating morphine in the central nervous system.

Dynamic aspects on acute tolerance to hexobarbital evaluated with an anesthesia threshold

Induction of acute tolerance was studied with hexobarbital in male rats. A threshold technique utilizing an EEG-criterion consisting of a burst suppression of 1 second or more (the SS) was used both to induce and maintain anesthesia. Hexobarbital was infused with an optimal dose rate of 15 mg/kg/min. The infusion was stopped at the criterion and restarted when no SS had been seen for 1 min. The doses of hexobarbital needed to maintain anesthesia were fairly constant around 3.5 mg/kg/min up to durations of 120 min which indicates that redistribution of hexobarbital is of minor importance in the present experiments. After different predetermined times of this fairly stable anesthesia, the rats were sacrificed, and concentrations in the cortex of the brain were determined with a HPLC-method. Maximal induction of acute tolerance was seen as a 45 percent increase in cortex concentration after 60 min of anesthesia, but already after 10 min a slight acute tolerance was recorded.

Clinical experience with the use of a temporary clip for intracranial aneurysm surgery. Analysis of eighteen cases.

SummaryAlthough the use of a temporary clip in intracranial aneurym surgery has been proposed by several Neurosurgeons in the past, its use today is not generally accepted. Modern surgical techniques have contributed to safer exposure and direct attack on the aneurysm. However, aneurysm surgery continues to be a challenge to the Surgeon and occasionally demands the use of a temporary clip.Eighteen cases operated on with the use of a temporary clip have been analysed. The occlusion time of the feeding vessel and location of the temporary clip have been related to the outcome. There was no relationship between occlusion time of the feeding vessel and outcome in this material, whereas location of the temporary clip seemed to be of importance for the outcome in cases with aneurysms located in the middle cerebral artery.

Effects of castration and testosterone treatment on the hexobarbital sensitivity in male rats

Castration increases the central nervous system (CNS) sensitivity to hexobarbital as measured by an EEG-threshold method. Testosterone treatment in doses from 1 to 5 mg/kg/day decreases CNS-sensitivity and restores threshold values in castrated rats to a level found in normal young adult male rats.