Perioperative myocardial perfusion scintigraphy at rest with technetium 99m methoxyisobutylisonitrile before and after coronary bypass operations.

Eighteen patients were examined at rest by technetium 99m methoxyisobutylisonitrile (99mTc-MIBI) myocardial scintigraphy 1 day before and 1 week after aorto-coronary bypass operation with planar and single photon emission tomography (SPET) imaging. One day postoperatively, a planar scintigraph in the intensive care unit (ICU) was done. Inter-observer variability was 3.8% for all examinations and for SPET alone, 3.9%. The quality of the planar images taken under emergency conditions in the ICU was quite comparable with those taken under routine conditions. The postoperative myocardial infarction in a patient who died 6 days later could clearly be demonstrated. In 16.2% of all segments which were hypoperfused at rest on preoperative scintigraphy, an amelioration of perfusion could be shown in the 1st week after the bypass operation. 99mTc-MIBI proved to be a useful agent to assess perioperative perfusion, in the ICU as well as under standard conditions.

[MRI in osteochondrosis dissecans]. / MRI bei der Osteochondrosis dissecans.

The osseous manifestations of osteochondrosis dissecans are well demonstrated by conventional and computerised tomography. Beyond that, magnetic resonance imaging (MRI) is effective in evaluating the vitality and loosening of an osseous dissecate. Subchondral cavities and cartilaginous defects are detected with high accuracy. Further, MRI seems to be a useful method in childhood to differentiate a variant irregularity of the osseous articular surface from definite osteochondrosis dissecans.

[Teratogenicity of anticonvulsant drugs (author's transl)]. / Zur Teratogenität von Antikonvulsiva.

Investigations were done on 111 children of epileptic mothers who used anticonvulsants in 93 pregnancies and none in 18 pregnancies. Hydantoinbarbiturate embryopathy was found in 7.1% after hydantoin monotherapy, in 17.6% after combination of hydantoin and barbiturates or primidone. No embryopathy was seen in children of untreated epileptic mothers. Children of untreated and treated epileptic mothers had an approximately equal frequency of marked single malformations and cerebral damage without dysmorphia. However, malformation and cerebral damage without dysmorphia was found significantly more frequently in children of mothers on anticonvulsant drugs with convulsions during pregnancy as compared to children of mothers without convulsions. Single manifestations and cerebral damage without dysmorphia are probably not caused by anticonvulsants but by convulsions during pregnancy.

[Interference of the tissue concentration of antibiotics with a salidiuretic. Behaviour of cephradine and cephalothin in brain tissue after additional administration of furosemide (author's transl)]. / Beeinflussung der Antibiotika-Konzentration im Gewebe durch ein Saluretikum.

Serum and brain tissue concentrations were determined after i.v. administration of 4 g cephradine to 11 patients of whom 6 were additionally receiving 40 mg furosemide t.i.d. peroral. Five further patients were given 4 g cephalothin i.v. All patients were undergoing a brain operation at the time of antibiotic administration. Between 60 and 100 min after dosage, cephradine decreased in the serum from 104.9 mcg/ml to 56.7 mcg/ml and in the brain tissue from 13.02 mcg/g to 8.37 mcg/g in the mean. Cephradine concentrations in serum were higher and in brain tissue lower when furosemide was given as well. These differences are statistically significant (p less than 0.01). Serum concentrations of cephalothin over the same period and in the absence of furosemide were very low with 32.2 mcg/ml at 60 to 70 min, and extremely low in the brain tissue (0.55 mcg/g in the mean) so that a trial with furosemide was not performed. Neither antibiotic was detectable in the cerebrospinal fluid. The differences in serum and brain tissue concentrations of cephradine in the presence and absence of furosemide demonstrate that special care must be taken when administering more than one drug.

[Cephradine in open heart serugery. Concentrations of cephradine in pericardial exudate and serum after cardiac surgery (author's transl)]. / Cefradin in der offenen Herzchirurgie. Cefradin-Konzentrationen im Perkardexsudat und Serum nach Herzoperationen.

The diffusion of cephradine into the pericardial exudate was measured in 19 patients undergoing heart surgery. Every patient received 2 grams of cephradine (=30 mg/kg) during a 20 minute infusion period, before, during, and after the operation, and than at intervals of 6 hours, together 8 grams per day. The highest mean serum level, 10 minutes after the end of the first injection was 150 microgram/ml and after repeated dosages 102.5 microgram/ml, and at the end of the infusion interval 3.2 microgram/ml in the mean. At the time of opening the pericardium the concentration of the substance in the pericardial exudate, 15, 30, 45 and 60 minutes after finishing the first injection, varied from 4.1 to 38.6 microgram/ml in the average. The postoperative maximum levels were higher than 50 microgram/ml and 6 hours after the respective administrations the levels varied between 12.83 and 15.77 microgram/ml in each case. These high concentrations of cephradine in the pericardial exudate could not be attributed to seepage of blood into the pericardium.-At specific "check points" bacteriological materials were taken. Out of 1168 specimens only 6.7% were bacteriological positive. Drains in wounds, the pleura or the pericardium were sterile in most cases. Intravenous catheters were contaminated only in 1%. However the contamination rate rises with period of storage. The results show that cephradine exhibits good diffusion into the exudate of pericardium. With the chosen dosage the concentrations of the antibiotic in the pericardial exudate are higher than the MIC values of most pathogen bacteria.

[The effect of increased extracellular calcium concentration on the hypoxic and pharmacologic hyperemia of skeletal muscle]. / Der Einfluss erhöhter extrazellulärer Kalziumkonzentrationen auf die hypoxische und pharmakologische Mehrdurchblutung des Skelettmuskels

The influence of an increased Ca concentration on reactive hyperemia, work induced vasodilation and pharmacologically induced dilation (adenosine, nifedipine, verapamil) was studied in the blood perfused gastrocnemius of dogs. Reactive hyperemia, work induced vasodilation and increased blood flow by administration of adenosine could not be influenced by increased extracellular Ca concentrations. A Ca antagonism was demonstrated for nifedipine and verapamil, especially with regard to a diminution of the drug eff.

[Studies on the degree of hypoxic and pharmacological coronary dilation (author's transl)]. / Untersuchungen zur Grösse der hypoxischen und pharmakologischen Coronardilation

On 11 isolated dog hearts, perfused with arterial blood of a donor dog, the degree of hypoxic dilatation and the maximum coronary blood flow achieved by adenosine were compared. The maximum coronary blood flow under adenosine infusion amounted to 455ml/minx100g, that means an increase of about 600% of the normal flow. If coronary venous pO2 was below 5mm Hg coronary blood flow was increased to 420ml/minx100g, which is 93% of the pharmacologically achieved maximum increase of the coronary blood flow. The difference between the maximum hypoxic and the maximum pharmacological dilatation is due to the method; it is caused by an increase of the extravascular component of coronary resistance under the influence of catecholamines in the case of hypoxic dilatation. It is pointed out that in order to achieve a maximum hypoxic dilatation oxygen pressure has to be below the critical value. It can be concluded that the intravascular component of coronary resistance is as low under hypoxic as under pharmacological dilatation.

[Experimental studies on the circulation of the vascular area of the subdiaphragm using a newly developed pulse-wave pump]. / Experimentelle Untersuchungen über die Durchblutung des subdiaphragmalen Gefässgebiets mit einer neuentwickelten pulswellenerzeugenden Pumpe

A new developed partial artificial heart system is presented, which allows pulsatile perfusion of vital organs. The results presented reveal the possibility to duplicate pressure curves and peak systolic pressure in the perfused area-similar to physiological preoperative measurements. The kidney function remains intact. Angiographically there is no damage of the kidney vessels evident. The results are compared with datas of other investigators. Especially there opinion about the disturbance of renal flow and function under nonpulsatile conditions are critically evaluated. A possible connnection between the postoperative renal failure after cardio-pulmonary bypass and non-pulsatile perfusion and other pathophysiological mechanisms are discussed.