Lumbar microdiscectomy under epidural anesthesia: a comparison study.

BACKGROUND CONTEXT: Lumbar microdiscectomy is most commonly performed under general anesthesia, which can be associated with several perioperative morbidities including nausea, vomiting, atelectasis, pulmonary aspiration, and prolonged post-anesthesia recovery. It is possible that fewer complications may occur if the procedure is performed under epidural anesthesia. PURPOSE: To investigate the safety and efficacy of epidural anesthesia in elective lumbar microdiscectomies. STUDY DESIGN: A prospective study evaluating the relative morbidities associated with epidural anesthesia and general anesthesia for lumbar microdiscectomy. PATIENT SAMPLE: Forty-three patients scheduled for primary lumbar microdiscectomy. Two cohorts were formed and were studied separately; one observational of all the 43 patients, and a second cohort of 17 patients who agreed to enter in the randomized trial. OUTCOME MEASURES: The clinical outcome was determined by the presence of postoperative pain, the absence of anesthesia-related complications, and the overall postoperative recovery. METHODS: This was a prospective study. With institutional review board approval, 43 consecutive patients were enrolled in the study. However, only 17 patients agreed to be randomized to receive either general or epidural anesthesia for the procedure; the remaining 26 patients selected the type of anesthesia of their preference. Recorded data for all patients included: age; total surgical time; occurrence of nausea, vomiting, atelectasis, or cardiopulmonary complication; ability to arise out of bed on the day of surgery; and the total number of inpatient hospital days. Postoperative pain and satisfaction were assessed only in the randomized cohort. RESULTS: There were a total of 43 patients, with a mean age of 38.1 years. The patients undergoing epidural anesthesia were marginally older than those undergoing general anesthesia. The epidural and general anesthetic groups were not different with respect to surgical time, pain assessed with a linear visual analogue scale, hospital stay, or the likelihood of arising out of bed on the day of surgery. There were no major cardiopulmonary complications in either group. Patients with epidural anesthesia had significantly less nausea and vomiting. CONCLUSIONS: Epidural anesthesia as an alternative to general anesthesia has shown less postoperative nausea and vomiting in lumbar microdiscectomy. Nevertheless, given the small number of patients, this study should be considered as preliminary, showing small differences in minor potential complications.     

Adjuvant immunotherapy in melanoma: a new approach.

Patients with metastatic cutaneous melanoma to two or more regional lymph nodes have an extremely poor prognosis despite radical lymphadenectomy. In an attempt to improve the survival and to determine the safety of a new method of tumor specific adjuvant immunotherapy in such a high risk group of patients, nine patients were studied. Three to four weeks after regional lymphadenectomy, each of them received a single intradermal injection of Bacillus Calmette-Guérin. Three weeks later, they were immunized by allogenic melanoma cells obtained from live donors with distant metastases. Each patient received three vaccinations, each from a different donor (except in one), to avoid development of HLA response, but maintaining exposure to melanoma antigens. No cultured melanoma cells were used. Each vaccine consisted of mitomycin-C treated tumor cells mixed with purified protein derivative (PPD) of tuberculin given intradermally once per month for 3 months. The patients were then observed with no further treatment. Utilizing the leukocyte migration inhibition test, there was some in vitro evidence of tumor specific cell mediated response which seemed to disappear 1-2 months postimmunization. At 5 years, five of the nine patients (55%) were alive free of disease. No autoimmune diseases were detected in any of the immunized patients. A major hindering factor for such an approach was the limited availability of the allogenic melanoma cells.     

Effects of Ethanol on NMDA Receptors in Brain: Possibilities for Mg2+ -Ethanol Interactions

The major excitatory neurotransmitter in the CNS is L-glutamate, and one of the subtypes of L-glutamate receptors, the N -methyl-D-aspartate (NMDA) subtype, has been found to be quite sensitive to inhibition by low concentrations of ethanol (5–50 mm). The NMDA receptor-ion channels are unique in that they exhibit a voltage-dependent blockade by physiological concentrations of Mg²⁺, a blockade that is relieved as the cell membrane is depolarized. Several lines of evidence also suggest that the activity of this receptor-channel complex may be regulated through a high-affinity Mg²⁺ site, which is distinct from the channel-blocking site and could even be located on the extracellular domain of the protein. This high-affinity Mg²⁺ site has been shown to increase the binding of N -[1-(2-thienyl) cyclohexyl]piperidine within the ion channel, as well as the binding of competitive antagonist such as 3-(±)-carboxypiperazine-4-yl)-[1,2]-propyl-1-phosphonic acid and the receptor coactivator glycine. The relationship between the acute effects of ethanol on receptor activation and the regulatory properties of Mg²⁺ is not yet known, although the hypomagnesemia that occurs in chronic alcoholism could certainly have implications for receptor function. A significant amount of molecular characterization of the multiple isoforms of the NMDA receptor-ion channel will be required before the role of Mg²⁺ can be clarified and any relationship between Mg²⁺ regulation and ethanol inhibition established.     

Technics of extensive lymph node curettage in cancer of the esophagus

During esophagectomy for cancer traditional lymph node curettage is performed extensively in the lower region but is practically nonexistent towards the upper zone, which fails to correspond to a satisfactory anatomic and oncologic exeresis. An operative technique has been adopted to extend lymph gland curettage, particularly in the anterior and superior mediastinum in the region of the recurrent and cervical chains. An analysis is performed of the advantages (increased survival) and inconveniences (increased postoperative morbidity) inherent in these extensive lymph node curettages.     

Course of pulmonary embolism

One hundred and fifty-five patients with a mean age of 59 years and suffering a recent pulmonary embolism (P.E.) underwent angiopneumography and phlebocavography before and after treatment. The P.E. was minimal in 42 cases (Muller less than 11) and severe in 113 cases (Muller greater than 11). There was an associated venous thrombosis (V.T.) in 134 cases (86%) affecting the iliac veins or vena cava in 44 cases (28%). Several types of treatment were used: heparin 66, SK 24, high dose UK 16, low dose UK + heparin 37, surgery 16. Fifty-two patients underwent a procedure to interrupt the I.V.C. Four patients received two types of treatment in succession. SK resulted in more rapid disappearance of the pulmonary clot than UK at the dose used but the results were comparable on the 15th day (SK = UK = H). With regard to V.T., the Marder index failed to reveal any significant difference between the types of treatment. However, SK resulted in the lowest therapeutic failure rate (19%) and it was the only agent which produced disobliteration of iliac or vena cava thromboses (6 cases out of 13), other types of treatment being ineffective (0 cases out of 28). The mortality rate was high (14%) but 86% of the patients who died had a massive P.E. (greater than 60%). The recurrence rate was less (6%) but recurrences were fatal in 6 cases out of 10. Sixty-four patients were seen again after a mean period of 20.7 months. Pulmonary sequelae were minor (CPC 4.6%, dyspnoea 18%). By contrast, one patient in two suffered from post-phlebitis syndrome. The latter was all the more common when obstruction of the proximal veins persisted after treatment. On the basis of these data, the authors emphasise the gravity of pulmonary thrombo-embolic disease: fatal in the early phase essentially as a result of recurrences, incapacitating in the late phase as a result of post-phlebitis syndrome. They note that proximal V.T. associated with P.E. is responsible for such complications. Such iliocaval disease must therefore be sought routinely by phlebocavography. Their presence justifies aggressive treatment designed to destroy them (SK) or protect against their consequences (I.V.C.I.).     

The significance of the levels of D-dimer in thrombotic conditions

A D Dimer ELISA test (Asserachrom D Di Stago) was used to quantify the modification of plasmatic D Dimer levels in two kinds of thrombotic diseases: DIC and deep venous thrombosis. Very high values were obtained in these two situations (m +/- sd): DIC (n = 22): 15.2 +/- 18.5 micrograms/ml. (Normal values were defined in 20 healthy subjects: 0.15 +/- 0.04 micrograms/ml). In DIC highest values were a bad prognosis, they were found in patients who died during the ten days following the diagnosis. In deep venous thrombosis the increase was not related to the size of the clot but to the endogenous fibrinolysis. An elevated concentration of D Dimer was often related to a good phlebographic evolution. During heparin therapy with standard heparin or low molecular weight heparin (LMWH) a greater decrease of D Dimer level was observed in patients with a good phlebographic evolution. Results expressed in percentage of decrease were (successful group against the failure group): J3/J10: 46.4 +/- 29.2 p. cent/13.4 +/- 11.0 p. cent (p less than 0.05); J7/J10: 52.3 +/- 31.5 p. cent/24.2 +/- 26.3 p. cent (p less than 0.05). The intensity of the decrease may have an indicative value for in vivo thrombolysis. This could be explained by a smaller clot mass to be lysed in successful group. During streptokinase treatment the D Dimer levels were very high (greater than 50 micrograms/ml). A problem of specificity could be evoked in presence of a massive quantity of fibrinogen degradation products levels.     

Long-term feeding studies in mice fed a diet containing irradiated fish II. 90-day toxicity study

Three groups of mice (F_2b generation of Part I study) were fed for 90 days, either stock ration or diets containing 45% fish, either non-irradiated or irradiated with 1.75 kGy. Equal amounts of cod and redfish (ocean perch) constituted the fish portion of the diet. Haematological and clinical chemical examinations revealed no treatment-related effects. There were no untoward terminal gross or histopathological changes. An initial lag in weight gain of males fed fish diets was attributed to reduced food consumption, due to the difference in texture of the fish diets compared with the stock ration.     

Porcine heterograft dressings for split-thickness graft donor sites.

As compared with previous methods of donor site care, procine heterograft dressings allow the donor site to heal faster, require less postoperative care, are associated with a lower infection rate and eliminate virtually all of the pain of the split-thickness wound. Our experience supports that of others. We believe our modifications of this technique to be superior to previous modalities of donor site care.     

Stereokontrolle. III. Geschwindigkeitskonstanten der iso- und syndiotaktischen anlagerung

The rate constants of isotactic and syndiotactic addition can be calculated from the rate constant k_w of the propagation reaction and the fractions of isotactic and syndiotactic dyads and triads. Corresponding equations are given for BERNOULLI trials and MARKOV trials of first order with respect to monomer dyads. The temperature dependence of dyad formation is discussed for MARKOV trials.