[Non-surgical ventricular training before arterial switch. Focus on an animal model in lambs]

One of the conditions for successful anatomical correction of transposition of the great arteries (arterial switch) or of double discordance (double switch) is the ability of the subpulmonary left ventricle to adapt to the systemic circulation when restored to its subaortic position. A balloon catheter designed for training the subpulmonary ventricle by progressive occlusion of the main pulmonary artery (NuMed) was implanted in six lambs aged 45 days and inflated progressively to obtain the maximum tolerated right ventricular pressure. Six controls were instrumented without balloon inflation. The experiment lasted 5 days. Progressive inflation of the balloon to a right ventricular pressure > 70% of the systemic (carotid) pressure led to bradycardia with venous desaturation and acidosis which regressed when the balloon was deflated. In one animal, progressive adjustment enabled a right ventricular pressure of 75% of the systemic pressure to be obtained throughout the last day of the study. No significant right ventricular hypertrophy was obtained. The value of this technique is in assessing the afterload reserve of the tested ventricle before surgical banding of the pulmonary artery, the first step to anatomical correction for restoration of concordance of double discordance or of transposition of the great arteries previously treated by a Senning or Mustard procedure.

Lymphoepithelial carcinoma of the parotid gland

BACKGROUND

Primary lymphoepithelial carcinoma of the parotid gland is a rare tumor with an increased incidence among Eskimos and Orientals. We reviewed our experience with parotid lymphoepithelial carcinoma and investigated its pathophysiology and possible association with Epstein-Barr virus.

METHODS

We performed a retrospective review of records of patients diagnosed with lymphoepithelial carcinoma of the parotid gland.

RESULTS

We identified two women of Hispanic origin diagnosed with primary lymphoepithelial carcinoma of the parotid gland. In one of the cases, the carcinoma was intimately associated with a benign lymphoepithelial lesion. In both cases, there was no demonstration of Epstein-Barr virus.

CONCLUSION

Primary lymphoepithelial carcinoma of the parotid gland may arise from malignant transformation of a benign lymphoepithelial lesion.

Teratomas of the head and neck

Teratomas of the head and neck are uncommon. They are composed of tissues from all three germ layers with varying degrees of differentiation. They arise from pluripotent stem cells and ectopic embryonic nongerm cells. Head and neck teratomas most commonly emerge during the neonatal period and are associated with airway obstruction and high rates of mortality in untreated patients. The tumors are usually benign, but when found during adulthood, they have a high incidence of malignancy. The most common site of occurrence is the cervical region and the nasopharynx. We presented a rare case of teratoma originating from the base of the tongue. This case is an example of the development of teratoma by pinching off of remnants of the three germinal areas, which become marginated in the normal migratory pathway as the different structures of the head and neck develop. The remnants developed into the predetermined organ systems, giving rise to the heterotopic tissues encountered. The recommended treatment for head and neck teratomas is surgical excision. When a patient is experiencing respiratory difficulty, establishment of an airway is a priority.

[Complications of the intravascular treatment of intracranial aneurysms using metal microcoils. Embolization using coils in intracranial aneurysms]

Embolization of intracranial aneurysms with coils. The authors present the results and complications of microcoils embolization of intracranial aneurysms in 28 patients. Fibers platinum microcoils were used (Target Therapeutic) 28 patients (males: 6, females: 22; mean age: 51 years) were treated, 27 suffered from sub-arachnoid hemorrhage (SAH) and one presented with a pseudotumoral syndrome (giant aneurysm). All patients were evaluated on the day of treatment, according to the World Federation of Neuro-Surgeon classification (W.F.N.S.) of SAH and after 4 months of follow-up. At a mean follow-up period of 4 months, according to Glasgow Outcome Scale (G.O.S.) there were 13 cases of good results, 5 cases of "moderate disability", 2 cases of "severe disability", 2 cases of "vegetative state" and 6 deaths. Complications were observed in 11/28 cases. Coils migration and malposition in the parent artery were linked to the procedure (mechanical detachable coil) and resulted in severe deficit (one case), transient disability (one case) or went unnoticed (4 cases). Primary or secondary complete occlusion was achieved in 8/28 patients (32%). A majority of cases (11 cases) ended with stable residual aneurysmal sac lumen while rebleeding occurred in 3 patients and was responsible for 2 deaths. In the third case a favourable outcome was obtained after balloon occlusion of the parent artery.

[Surgery of acoustic neurinoma in the elderly]

Eleven patients, between 70 and 85 years old, with acoustic neurinoma, were operated by translabyrinthic approach. The size of the tumor was between 2 and 4 cm in five cases, 4 cm or more in six cases. Complete tumor removal was possible in six cases (55%), in five cases (45%) residual tumor was left behind. Complications included cerebrospinal fluid leakage (2 cases), meningitis (1 case), and hemorrhage (1 case, fatal four days later). Anesthetic management is described.

Pharmacokinetics of salicylates in elderly

In order to study changes in the pharmacokinetics of salicylates in old people, we used two groups of inpatients without hepatic or renal impairment: the first comprised 15 patients more than 65 years old, mean age 77 years; the second, 7 patients of mean age 21 years. Each patient was given 1 g of acetylsalicylic acid orally in the morning while fasting. Blood samples were subsequently taken after 30, 60 and 90 min and 2, 3, 4, 6, 8, 10, and 24 h. Fluorimetric assay results were analyzed kinetically with a mathematical model corresponding to a single diffusion compartment model. The results showed only a slight increase in the absorption half-time in old subjects, and a marked increase in elimination half-time (3.71 and 2.38 h in old and young subjects, respectively; t = 2.33: p less than 0.05) and in the volume of distribution (5.51 and 3.83 liters respectively; t = 3.20: p less than 0.1). On the other hand, bioavailability varied little, as did metabolic clearance. This study confirms that intestinal absorption of this drug is not much impaired in old people, while hepatic and/or renal elimination functions are changed. This finding agrees with results found for aminopyrine, antipyrine, and digoxin.

[Interaction of salicyl compounds and other non-steroidal anti-inflammatory agents: pharmacokinetic study of phenylbutazone-aspirin combination in man]

The pharmacodynamic interaction between phenybutazone and aspirin was studied in 9 patients. The levels of phenylbutazone were estimated by gas-chromatography and verified by mass-spectrometry. When phenylbutazone was administered together with salicylates a decrease in the bioavailability of phenylbutazone was demonstrated, but there was no significant variation in the absorption and elimination constants or in the half-life. The variations were much less than those observed with other nonsteroid anti-inflammatory drugs (indometacine, naproxen, fenoprofen). These interactions must be taken into account in the long-term treatment of cases of inflammatory rheumatism.