Proposal of a sequential treatment methodology for the safe reuse of oil sludge-contaminated soil.

In this study sequential steps were used to treat and immobilize oil constituents of an oil sludge-contaminated soil. Initially, the contaminated soil was oxidized by a Fenton type reaction (13 wt% for H(2)O(2); 10mM for Fe(2+)). The oxidative treatment period of 80 h was carried out under three different pH conditions: 20 h at pH 6.5, 20 h at pH 4.5, and 40 h at pH 3.0. The oxidized contaminated sample (3 kg) was stabilized and solidified for 2h with clay (1 kg) and lime (2 kg). Finally, this mixture was solidified by sand (2 kg) and Portland cement (4 kg). In order to evaluate the efficiency of different processes to treat and immobilize oil contaminants of the oil sludge-contaminated soil, leachability and solubility tests were performed and extracts were analyzed according to the current Brazilian waste regulations. Results showed that the Fenton oxidative process was partially efficient in degrading the oil contaminants in the soil, since residual concentrations were found for the PAH and BTEX compounds. Leachability tests showed that clay-lime stabilization/solidification followed by Portland cement stabilization/solidification was efficient in immobilizing the recalcitrant and hazardous constituents of the contaminated soil. These two steps stabilization/solidification processes are necessary to enhance environmental protection (minimal leachability) and to render final product economically profitable. The treated waste is safe enough to be used on environmental applications, like roadbeds blocks.

Mortality in elderly patients with thermoregulatory failure.

Fifty-four elderly patients with thermoregulatory failure were evaluated retrospectively. The most commonly associated cause was underlying sepsis, which occurred in 78% of cases. Underlying conditions that increased the incidence of hypothermia were hypoproteinemia (50%), cachexia (30%), and neuroleptic medications (21%), most commonly thioridazine. Digoxin toxicity was a common finding (20% of all cases). One third of the patients developed hypothermia in warm months and half of them developed it while in the hospital. Patients who presented with hypothermia from out of the hospital had lower temperatures, were more bradycardic and hemoconcentrated, and died more rapidly than the in-hospital group. This could be explained by lower outside temperature or delay in diagnosis and treatment of the underlying disease. The overall mortality rate was extremely high (74%) in both groups. The mortality rate was not affected by age, sex, or degree of hypothermia. We conclude that thermo-regulatory failure in the elderly can occur in warm as well as cold environments or climates. The development of hypothermia in elderly patients should be promptly treated as sepsis unless proven otherwise, in light of the poor prognosis of this condition.

Parkinsonism with 'on-off' phenomena. Intravenous treatment with levodopa after major abdominal surgery.

Continuous intravenous infusion of levodopa was used for eight days to manage a parkinsonian patient with "on-off" fluctuations who underwent abdominoperineal resection for carcinoma of the rectum. Reasonable control of parkinsonism was obtained initially with small doses of levodopa, but more than 4 g daily were eventually required. No adverse effects on cardiac rhythm, blood pressure, or gastrointestinal function occurred. Frequent adjustment of levodopa dosage was necessary in view of continuing "on-off" fluctuations. Severe akinesia, which can cause dysphagia, respiratory complications, and venous stasis in the legs, can benefit from this method of management after major abdominal surgery in a patient with advanced parkinsonism.

Effect of an opiate antagonist on movement disorders.

Animal experiments suggest that opiate peptides might play a role in extrapyramidal function. This hypothesis was tested by administering the opiate antagonist, naltrexone, in doses sufficient to antagonize exogenous opiates, to patients with parkinsonism and Huntington's disease. No improvement in the clinical features of either disorder was noted.

Treatment of Huntington disease with a cholinergic agonist.

The involuntary movements of Huntington disease may be related to cholinergic hypofunction in the striatum. For this reason, the effect of a direct cholinergic agonist, arecoline, was studied in six patients with this disorder. Rather than improving the chorea, arecoline tended to exacerbate the choreic movements. Arecoline did produce significant alterations of blood pressure, heart rate, and body temperature, probably by central cholinergic stimulation.

Endogenous opiates mediate cardiac sympathetic inhibition in response to a pressor stimulus in rabbits.

Two different patterns of response to a pressor stimulus occurred in conscious rabbits. This difference was not apparent when a depressor stimulus was applied. At levels of mean arterial pressure exceeding 120 mmHg one group of animals exhibited a marked bradycardia which was due to sympathetic inhibition in addition to vagal activation while this sympathetic component appeared to be lacking in the second group of animals. Naloxone (0.1 mg/kg i.v.) markedly reduced the sympathetic inhibition elicited by phenylephrine but had no significant effect on the reflex vagal stimulation. Naloxone thereby abolished the difference in sensitivity of baroreflex control of heart rate in response to a pressor stimulus between the two groups of rabbits. Naloxone did not influence the sensitivity of the reflex response to nitroprusside. Morphine (2 mg/kg) increased the vagal component of the baroreceptor reflex in response to a pressor stimulus and the sensitivity of the reflex response to nitroprusside in all the rabbits, and this was antagonized by naloxone (0.1 mg/kg). Morphine also potentiated and naloxone antagonized the bradycardic response at levels of MAP exceeding 120 mmHg, in those rabbits which appeared to lack the cardiac sympathetic inhibitory component of the reflex. The results show that endogenous and exogenous opiates can increase the reflex bradycardia in response to a pressor stimulus in the conscious rabbit. The difference in baroreflex sensitivity in different animals may result from their varying ability to activate endogenous opioid systems which depress cardiac sympathetic activity.

Cardiotoxicity of interferon. A review of 44 cases.

Cardiovascular complications have occurred in clinical trials of interferon. We review herein experience to date of cardiotoxicity with all types of interferons in cancer patients. The most common presentations of cardiotoxicity were cardiac arrhythmia, dilated cardiomyopathy, and symptoms of ischemic heart disease, including myocardial infarction and sudden death. The cardiac effects were not related to the daily dose, cumulative total dose, or period of therapy. Some of the patients in whom interferon has caused cardiovascular sequelae have had a history of coronary heart disease or have previously been given chemotherapy with drugs known to be cardiotoxic. In most of the patients, cardiac toxicity was reversible following the cessation of the drug therapy.

Body positional effect on gas exchange in unilateral pleural effusion.

The positional effect on gas exchange was studied in eight patients who had unilateral pleural fluid without clinical or radiologic evidence of parenchymal lung disease. In all eight patients, PaO2 values were higher when the lung with the pleural fluid was uppermost. The mean PaO2 in this position was 71.9 +/- 9.3 mm Hg (mean +/- SE) compared with 66.7 +/- 8.7 mm Hg in the lateral decubitus position with the pleural fluid lowermost. The mean difference in PaO2 between the two positions was 5.1 +/- mm Hg (p less than 0.005). Larger positional differences were found in the patients with the smallest pleural effusions. These results are probably due to perfusion of areas of unventilated lung, accentuated by gravity with a consequent increase in shunting. A large effusion also causes a decrease in perfusion, so that ventilation-perfusion mismatching is decreased and the positional effect on gas exchange diminished.

Diuretic-induced severe hyponatremia. Review and analysis of 129 reported patients.

Thiazides were responsible for severe diuretic-induced hyponatremia (serum sodium level < 115 mEq/L) in 94 percent of 129 cases reported in the literature between 1962 and 1990. The hyponatremia developed within 14 days in most of the patients receiving thiazides but in none of the patients who were treated with furosemide. Diuretic-induced hyponatremia was four times more common in women than in men. Advanced age was not associated with a higher tendency for hyponatremia. In the majority of the patients who received thiazides, excess antidiuretic hormone activity, hypokalemia, and excess water intake were accompanying findings which, singly or together, appeared to contribute to the development of hyponatremia. In 12 patients, mortality was directly related to hyponatremia. Rapid average correction of hyponatremia and a relatively high total correction (over 20 mEq/L) in the first 24 h were significantly associated with higher mortality or demyelinating syndrome. The presence of neurologic signs is an indication for active sodium replacement. The onset of thiazide-induced hyponatremia may in some cases occur within 1 day and therefore needs to be corrected rapidly, but within a total elevation of 20 mEq/L in the first 24 h. Where the onset is judged to have been slow (over several days), the level should be corrected at a slow rate, up to a total of 12 to 15 mEq/L in 24 h.

Factors influencing admission or nonadmission of the aged to the hospital.

A prospective study was carried out to determine which social, functional, or medical factors influenced the decision to admit or not to admit aged people to a general hospital in Israel. The study also focused on characteristics of patients admitted to the geriatric ward of the medical division as distinct from those sent to the internal medicine ward. Two hundred patients over the age of 65 were examined during ten consecutive intake days for the internal medicine ward over a period of five weeks. One hundred and sixty-seven were interviewed in the emergency departments, and the others after transfer from other departments by prearranged consultation. Thirty-five per cent were not admitted, 28 per cent were admitted to internal medicine, and 26 per cent were admitted to the geriatric department. Social factors played little part in the selecting process, the dominant need being acuteness and severity of illness. However, patients in the geriatric ward were found to be functionally much more disabled in regard to mobility, mental state, and incontinence. This was also reflected in a longer average stay of 15 days compared with nine in internal medicine, a higher mortality (19 per cent as against 7 per cent) and a higher degree of disability on discharge from hospital.