Low-grade endometrial stromal sarcoma with intracardiac extension. Evolution of extensive smooth muscle differentiation and usefulness of immunohistochemistry for its recognition and distinction from intravenous leiomyomatosis.

This case, a rare example of low-grade endometrial stroma sarcoma with extensive smooth muscle differentiation which extended to the inferior vena cava and cardiac chambers closely resembling intravenous leiomyomatosis grossly and microscopically, illustrates the importance of extensive sectioning and the usefulness of immunohistochemistry. Although spindle cell components arranged in interlacing bundles consistent with smooth muscle differentiation were recognizable in the primary tumor (on retrospective review), extensive smooth muscle differentiation in the recurrent tumors masked prototypical morphologic features of stromal sarcoma and only small neoplastic stromal components were preserved in limited areas, leading to initial failure to distinguish the lesion from intravenous leiomyomatosis. The immunophenotyping disclosed two distinct cell populations in the tumor: i.e. vimentin-positive and smooth muscle marker negative stromal cells, and vimentin-negative spindle-shaped desmin-positive smooth muscle cells. Our observation suggests that the predominance of a smooth muscle component in such a tumor can be misleading and does not always warrant a diagnosis of intravenous leiomyomatosis, nor does it predict a benign clinical course. This case also provides an insight into the relationship of the endometrial stroma and myometrium, and their cell of origin and the histogenesis of endometrial stromal sarcoma.

[Continuous intradural anesthesia in geriatric patients undergoing orthopedic and traumatologic surgery]. / Anestesia intradural continua en pacientes geriátricos sometidos a cirugía ortopédica y traumatológica.

OBJECTIVES: The aim of the study was to prospectively evaluate the results of continuous intradural anesthesia with 18G Tuohy needle and 20G catheter in geriatric patients. MATERIAL AND METHODS: We studied 70 patients with a mean age of 75.9 +/- 10.8 years who were subjected to orthopedic or traumatologic surgery of the lower extremities with a duration of 104.6 +/- 53.6 min. RESULTS: Success index was 95.7%. The initial dose of 1% tetracaine was 10.36 +/- 3.96 mg, the second dose in 29 patients was 7.2 +/- 2.7 mg, the third in 7 cases was 7.40 +/- 2.47 mg, and the total dose was 14.56 +/- 5.6 mg. The metameric level was between T8 and T11 in 80.32% of patients. Peroperative complications were limited to paresthesia in 5 cases (7.14%) during insertion of the catheter, difficulties in catheter placement in one case (1.42%), and accidental catheter extraction during withdrawal of the needle in 2 cases (2.85%). Ten patients (14.28%) presented arterial hypotension (pressure decrease greater than 30% of baseline systolic arterial pressure). During the postoperative phase there were 3 cases of slight headache after dural puncture (4.28%) that recovered with conservative treatment, and one case of lumbalgia at the puncture zone (1.42%). CONCLUSIONS: Continuous intradural anesthesia with the material used in this study is technically easy. It allows to accurately reach the desired metameric level, avoiding massive sympathetic blockade, and providing a steady hemodynamic condition. All these effects are essential for anesthesia in geriatric patients.

Enzymatic basis of thiol-stimulated secretion of porphyrins by Escherichia coli.

1-Thioglycerol (TG) stimulates the synthesis of porphyrin in aerobically growing Escherichia coli. Here the levels of delta-aminolevulinate biosynthetic enzymes in untreated and TG-treated E. coli THU and PUC2 (a mutant of THU which overproduces porphyrins in the presence of thiols) cells were determined. TG treatment elevated the activity of glutamyl-tRNA reductase in both strains. The increased activity was not caused by activation of preexisting enzymes by thiols or by oxidizing agents but was dependent on new protein synthesis.

Risk factors for arthroscopic popliteal artery laceration.

A case report is presented in which a patient with well-documented pigmented villonodular synovitis sustained a disruption of the popliteal artery without evidence of penetration of the posterior capsule. The patient had had several extensive open synovectomies in the prior 20 years. These included popliteal space exposure and dissection. At the time of open arterial repair, multiple nodules of pigmented scar were noted densely binding the popliteal artery to the surrounding muscle and fascial tissues. The arthroscopist should be aware that distension and instrumentation of the knee joint in such patients should be performed with extreme care to avoid arterial disruption.

Continuous spinal anaesthesia versus single dosing. A comparative study.

Continuous and single dose spinal anaesthesia were compared in a prospective randomized fashion in 108 patients undergoing orthopaedic surgery. Continuous spinal anaesthesia was via a 20 gauge polyamide multiperforated catheter introduced through an 18 gauge Tuohy needle. Single-dose spinal anaesthesia was performed with a 24 guage x 103 mm Sprotte spinal needle. The mean local anaesthetic dose for the continuous technique was 38.4 (SD 16.5) mg as hyperbaric lignocaine 5%, and for the single-dose spinal anaesthesia 10.8 (SD 2.2) mg as hyperbaric bupivacaine 0.5%. Segmental levels reached with the initial dose did not differ significantly between the two groups. Mean time required to perform continuous spinal anaesthesia was 6.7 (SD 3.9) min, which was longer than for single dose 4.9 (SD 2.8) min (P < 0.05). The onset time and efficacy of anaesthesia, and the duration of the operation were similar in the two groups. Analgesia was inadequate in six patients who received continuous spinal anaesthesia (11%) and one patient who received single dose (2%) (P = 0.18). Hypotension was more frequent in those receiving single doses (P < 0.05). Caudal rotation of the outlet needle orifice to advance the catheter correlated with inadequate analgesia (P < 0.01, r = 0.38). There were no significant differences in the incidence of post-operative complications.

A comparative study of analgesia after knee surgery with intraarticular bupivacaine, intraarticular morphine, and lumbar plexus block.

Following arthroscopic surgery of the knee, 60 ASA I-II patients were randomly allocated to three different groups (n = 20 each) in an attempt to establish the best postoperative analgesic protocol: 20 ml of bupivacaine (0.25%; 50 mg) intra-articularly (IA) (Group 1); continuous three-in-one lumbar plexus block using a catheter to administer 0.25 ml/kg of bupivacaine (0.25%; single-shot) plus continuous pump infusion of the same drug (0.03 ml.kg-1 x h-1 of 0.25% bupivacaine for 24 h) (Group 2); or 1 mg of morphine with 20 ml of saline IA (Group 3). The results were appraised in a double-blind manner, and the degree of postoperative pain was evaluated by visual analog scale (VAS) at constant hourly intervals for the first 24 h, by the incidence of secondary effects, and by the need for complementary analgesia. Group 2 (three-in-one) VAS values were lower 16 and 24 h after surgery and also globally (P < 0.05), with respect to the other two groups. Five patients in Groups 1 and 3 required complementary analgesia, while three patients in Group 1 suffered nausea. No other secondary effects were observed. We conclude that all three analgesic methods proved efficient, as reflected by the scant requirements for additional analgesics and the degree of expressed patient satisfaction. However, lumbar plexus block (three-in-one) with continuous bupivacaine infusion was most effective, and, although it constitutes an added technique, its scant complications and easy performance make its use advisable.