A case of severe intoxication by tricyclic antidepressants with persistence during 14 days of abnormally high plasma imipramine levels is reported. The various factors capable of maintaining plasma imipramine at a high level are discussed. They include mechanical factors (intestinal absorption), ventilation under positive end-expiratory pressure, alterations of hepatic metabolism by other drugs such as metronidazole or cimetidine, and changes in tissue distribution. Attention is drawn to the risks inherent in the various treatments used against acute intoxications and in combined chemotherapy during intensive care generally. When such drugs are necessary, the plasma levels of those with higher toxicity should be monitored.
In a randomized cross-over study 10 healthy male volunteers received a single 1 g dose of 6-[R]-2-3-methylsulfonyl -2- oxo-imidazolisine -1- carboxamido) -2- phenyl-acetamido]-penicillanic acid sodium salt (mezlocillin) and of ampicillin, either intravenously or intramuscularly. Following the intravenous loading dose, mean peak serum levels of 101 micrograms/ml for mezlocillin and 91.5 micrograms/ml for ampicillin were recorded. The ultimate half-life t 1/2 of mezlocillin (46.4 min) was slightly shorter than that of ampicillin (52.4 min). Similarly, the total volume of distribution of mezlocillin (24.1 l) was slightly inferior to that of ampicillin (29.4 l). The proportions of the dose administered recovered in the urine of 24 hours were 50.4 % for mezlocillin and 69.9 % for ampicillin. The total clearances of the two antibiotics were not significantly different, but the renal clearance of mezlocillin (186.6 ml/min/1.73 m2) was significantly lower than that of ampicillin (309.5 ml/min/1.73 m2). Following intramuscular injection, the mean peak serum levels obtained were 15.6 microgram/ml with mezlocillin and 15.1 micrograms/ml with ampicillin. The half-lives of the antibiotics were 50.0 min and 57.2 min respectively. The bioavailable fractions of mezlocillin and ampicillin, as measured from the areas under the serum concentration curves wer 63 % and 75 % respectively of the values determined after intravenous injection. The oral administration of 1 g probenecid one hour before an intramuscular injection of mezlocillin increased the peak serum level and area under the curve by 65 % and decreased the total clearance, renal clearance and apparent volume of distribution by 38 %, 52 %, and 35 % respectively. However, the ultimate half-life was not significantly altered (50.5 min without, and 52.0 min with probenecid).
In the authors' experience gallstones, particularly when minute, constitute the most frequent cause of acute pancreatitis. The size of the calculi (about one millimeter) explains the two major characteristics of microlithiasis: it is "illegible" and therefore difficult to detect and frequently undiagnosed; it is "migratory", like urinary lithiasis, and may be responsible for transient hyperpressure in the pancreatic ducts resulting in acute pancreatitis. In all cases of acute pancreatitis, the possibility of biliary microlithiasis should be thoroughly investigated and relapses should be prevented by cholecystectomy with clearing of the biliary ducts under radiosurgical and/or endoscopic control.
Antiepileptic drugs are thought to be responsible for an abnormally high incidence of post-partum haemorrhages. Data on perinatal mortality of epileptic patients are discordant. Children of epileptic mothers are frequently undersized. Although they have an incidence of malformations 1.25 times higher than average, these may be associated with the severity of seizures and with the disease itself, since there is no evidence that anticonvulsants are teratogenic. The influence of pregnancy on epileptic attacks is extremely variable. Seizures occurring during a pregnancy need not necessarily occur during subsequent pregnancies. There seems to be a positive correlation between eclampsy, late epilepsy, familial epilepsy and abnormal EEGs. Status epilepticus is unusual in child-bearing women. The dosage of several antiepileptic drugs needs to be increased during pregnancy, probably because of accelerated metabolism and reduced intestinal absorption. Decrease in plasma protein levels seems to be of little significance. Antiepileptic drugs which cross the placenta are usually excreted by the newborn within a week, but children of mothers who are given diazepam during delivery may be intoxicated. Drug concentrations in milk are low, but the child must be supervised if the mother takes phenobarbitone or diazepam. However, in most cases breast-feeding is safe. Pregnant epileptic women should be carefully examined throughout pregnancy and post-partum for obstetrical reasons and because the drugs they absorb may give abnormal blood levels.
The results of 36 follicular punctures for in vitro fertilization (IVF) performed at the Maternity unit of Hôpital Tenon, Paris, between January and June 1981 are reported. To collect a pre-ovulatory ovocyte by follicular puncture through laparoscopy requires extremely accurate monitoring of ovulation to make sure that the ovocyte collected has completed its nuclear and cytoplasmic maturation in vivo. The criteria for puncture time are the beginning of LH plasma peak level in spontaneous cycles and injection of HCG in stimulated cycles. In this series the ovocyte collection rate was 60% on average. Failures were mostly due to the local status of the genital tract in the women selected for attempted IVF, since all of them had permanent tubal sterility consecutive to severe pelvic inflammatory lesions. The percentage of ovocytes found to be mature was higher in spontaneous than in stimulated cycles. Out of 13 pre-ovulatory ovocytes collected, 8 were fertilized in vitro. Four could be transferred into the uterus, resulting in two pregnancies which had to be interrupted at an early stage. IVF demands full availability of the surgical and laboratory teams concerned.
In the absence of reliable objective methods to assess traumatic muscle injuries in athletes, the authors have chosen to perform routine ultrasonography. Taking the thigh as an example, they describe the appearance of normal muscles on ultrasonographic images and compare these with CT sections. The results of examination in 61 athletes with traumatic injury are reported. The different ultrasonic patterns are described and compared with surgical findings in 16 cases. All lesions could be detected by ultrasonography, and 87% were correctly identified. Ultrasonography provides direct and clear imaging of the muscles. It constitutes an excellent means of detecting severe lesions and locating them accurately before surgical repair. It is highly reliable and deserves to be adopted by all physicians and surgeons specialized in sports medicine.
