[Improvement of oxygenation in thoracic surgery with one-lung ventilation using a new intraoperative CPAP device]. / Untersuchungen zur Verbesserung der Oxigenierung bei thoraxchirurgischen Eingriffen unter Ein-Lungen-Beatmung mit einem neuen intraoperativen CPAP-Gerät.

For thoracic surgery with one-lung ventilation, the use of CPAP for the non-ventilated lung can improve oxygenation. We studied the use of a newly developed CPAP device in 28 patients undergoing single-lung ventilation. This device was easy to use, in particular because the components are familiar to every anesthesiologist. The use of +5 mbar CPAP improved oxygenation by an average of 39.5 mm Hg; +10 mbar CPAP brought about an improvement of 89 mm Hg. Pulse oximetry proved useful in monitoring adequate oxygenation.

[Intravenous analgesia with ketamine for emergency patients]. / Intravenöse Analgesie mit Ketamin bei Notfallpatienten.

Twenty traumatized patients suffering from fractures and soft tissue injury were given either 0.25 mg/kg or 0.5 mg/kg ketamine intravenously for analgesia. Within 5 min effective analgesia was present in both groups and lasted for 10-15 min. The higher dose of ketamine led to an impairment in the level of consciousness. These findings were in agreement with plasma levels of ketamine: in the 0.25 mg/kg group the plasma levels (median) were 167 ng/ml after 5 min, 92 ng/ml after 10 min, 82,5 ng/ml after 15 min, and 46 ng/ml after 30 min (n = 4). In the 0.5 mg/kg group the plasma levels (median) were 238 ng/ml after 5 min, 189 ng/ml after 10 min, 135 ng/ml after 15 min, and 118 ng/ml after 30 min. Considering the influence on consciousness, we recommend the administration of 0.25 mg/kg ketamine intravenously for analgesia in traumatized patients without head injury. It may be necessary to repeat the same dose if pain re appears.

[Comparative study of the behavior of intraocular pressure in anesthesia induction by diazepam and midazolam]. / Vergleichende Untersuchung zum Verhalten des intraokularen Druckes unter Narkoseeinleitung mit Diazepam und Midazolam.

20 patients scheduled for cataract extraction were randomly assigned to two groups. Before anaesthesia was induced, group A patients received 0.3 mg/kg body weight diazepam, whereas group B was given 0.15 mg/kg body weight midazolam. The ocular pressure, blood pressure, pulse and respiratory rate were determined and a capillary blood gas analysis was performed prior to the administration of the tranquilizer (time I), after the patient fell asleep (time II) as well as 5 min. after intubation (time III). Before intubation the patients received fentanyl and succinylcholin. The reduction in ocular pressure is initially somewhat less in the midazolam group, but is identical to that in the diazepam group at time III where it fell to 57% of the preinduction value. In combination with fentanyl, these two drugs are suitable for anaesthesia in intraocular surgery.

[Intramuscular ketamine analgesia in emergency patients. II. Clinical study of traumatized patients]. / Untersuchungen zur intramuskulären Ketaminanalgesie bei Notfallpatienten. II. Klinische Studie an traumatisierten Patienten.

Twenty traumatized patients suffering from burns, fractures and bruises were given either 0.5 mg/kg or 1.0 mg/kg ketamine intramuscularly for analgesia. Within 10 min effective analgesia was present in both groups. In the 1 mg/kg group analgesia was more intense, and of longer duration. The higher dose of ketamine led to an impairment in the level of consciousness. Some of the patients of this group were markedly desorientated. The highest plasma levels of ketamine were 147 ng/ml (median) in the 0.5 mg/kg group at 30 min and 474 ng/ml (median) in the 1.0 mg/kg group at 15 min. As to side-effects, 3 patients reported dizziness and 1 patient vomited. Intramuscular applications of 0.5 mg/kg ketamine affords a good but short lasting analgesia with few side-effects.

[POR 8 (ornipressin). Local vasoconstrictive effect and hemodynamic activity during surgery in ENT clinics]. / POR 8 (Ornipressin). Lokaler vasokonstriktorischer Effekt und hämodynamische Auswirkungen bei Eingriffen in der Hals-Nasen-Ohren-Klinik.

POR 8 (ornipressin) at a concentration of 5 IU in 10 ml of 1% lidocaine was used as a local vasoconstrictor in 262 ENT operations. Anaesthesia was carried out with either halothane or enflurane, or with diazepam and fentanyl. The doses of POR 8 lay between 2.7 IU and 3.5 IU. Under inhalational anaesthesia there was a good vasoconstriction in 85% to 90%, and anaesthesia with diazepam-fentanyl in 60% to 83% of cases, depending on the site of operation. There should be a 10-20 minute interval between infiltration and the beginning of surgery. Under inhalational anaesthesia the systolic blood pressure fell by 10% after infiltration of POR 8, when the diastolic blood pressure rose by 6%. During diazepam-fentanyl anaesthesia the systolic blood pressure increased by 23%, the diastolic by 27%. POR 8 was not found to have an antidiuretic effect. There was no difference between the osmolality, sodium and potassium levels of 30 patients measured before infiltration and 24 hours later. Because of the minimal side effects of POR 8 on the cardiovascular system during inhalational anaesthesia we recommend the use of these substance as a local vasoconstrictor instead of epinephrine.

[Comparative clinical studies on parenteral and oral premedication in childhood with special regard to the volume and acidity of the gastric juice]. / Vergleichende klinische Untersuchungen zur parenteralen und oralen Prämedikation im Kindesalter unter besonderer Berücksichtigung der Magensaftmenge und Azidität.

90 children of age between 1 and 10 years who were scheduled for adenotomy were randomized into 3 premedication-groups. Group 1 received no premedication, group 2 chlorprothixene 1 mg/kg i.m. and group 3 chlorprothixene 2 mg/kg orally. Prior to induction of anaesthesia 63.3% of the unpremedicated children were anxious or crying, in contrast to 23.3% of the children given oral or i.m. premedication. With respect to the reaction on venepuncture with a Butterfly G 23, there was no significant difference between the groups. The volume of gastric acid (median values) was 0.056 ml/kg in group 1, 0.063 ml/kg in group 2, and 0.068 ml/kg in group 3, with a pH of 2.0, 1.5 and 2.0 respectively. One hour after operation 44.8% of the children in group 1, 92.6% in group 2 and 84.6% in group 3 were calm or sleeping. Premedication definitively improves the pre- and postoperative management of children. We now recommend oral chlorprothixene for the premedication of children because the effect of this oral premedication is equivalent to i.m. application, and the oral route has no influence on the quantity or acidity of gastric contents.

[Experiences with high-frequency jet ventilation in operations of the larynx and trachea]. / Erfahrungen mit der High-Frequency-Jet-Ventilation bei Eingriffen am Kehlkopf und an der Trachea.

60 ENT patients were ventilated with the high frequency jet ventilation method, using endotracheal catheters during 50 cases of laryngeal and 10 cases of tracheal surgery. Ventilation was carried out with equipment of type MK 800 (Acutronic Ltd.) using the following parameters; rate: 150/min, insufflation time: 30-40%, pressure: 0.7-2.1 bar, and flow minute volume (FMV) 7-23 1. Anaesthesia was carried out with flunitrazepam or diazepam, fentanyl and succinylcholine. Surgical view was very good indeed, thanks to the thin jet catheter (4.7 mm outer diameter) in the trachea. At the low "tidal volumes" and intratracheal pressure changes when a rate of 150/min was used, no movement of the vocal cords was seen, so that microsurgery was easy to perform. There were no cases of hypoxia. The median pO2 value was 193 mm Hg. When a flow minute volume of 200 ml/kg was used for patients with normal lung function, and 250 ml/kg for those with impaired function, ventilation was quite adequate. The quality of ventilation should always be checked, and corrected as necessary, by blood gas analyses. Hypoventilation occurred when the FMV was less than 250 ml/kg in patients with decreased lung function, when the tip of the catheter was inserted into a mainstem bronchus or near to the tracheostoma, or when gas escape was obstructed. Unhampered gas escape must be present at all times, because otherwise intratracheal pressure rises and ventilation becomes insufficient. If the pressure increase is marked under these circumstances it can even lead to a pneumothorax.

[Intramuscular ketamine analgesia in emergency patients. I. Clinico--pharmacokinetic study]. / Untersuchungen zur intramuskulären Ketaminanalgesie bei Notfallpatienten. I. Klinisch-pharmakokinetische Studie.

Effective analgesia under conditions of emergency and disaster is still a problem which can be considered as unsolved. The i.m. administration of ketamine in subanaesthetic doses could be one step forward, particularly in regard to a possible application by paramedical personnel. In order to evaluate this hypothesis, we compared 2 groups of 6 patients each, who received either 0.5 mg/kg or 1 mg/kg ketamine respectively i.m. for p.o. pain relief after tonsillectomies. The analgesic efficacy, the levels of consciousness, the blood pressure values and the ketamine plasma levels demonstrated, that effective analgesia can be obtained within 10 min following either dose. The dosage of 1 mg/kg however was followed by a transient impairment of the levels of consciousness. The pharmacokinetic data may lead to the conclusion that analgesia starts above plasma levels of 100 ng/ml. Important side effects were not be observed in these few cases. A further study, which has almost been completed, will demonstrate whether the same results apply to emergency out-patients suffering from fractures, burns etc.

Ornipressin as vasoconstrictor in rhinosurgery.

The haemostatic effect of a high concentration of ornipressin 5 IU/10 mls lidocaine was studied in 127 patients undergoing rhinosurgery under two types of general anaesthesia. Under halothane/enflurane anaesthesia blood pressure and heart rate remained nearly constant up to 15 minutes following local injection of ornipressin into the nasal tissues. Good haemostasis was achieved in 86.5 percent of cases. Under diazepam/fentanyl anaesthesia an elevation of blood pressure was observed following infiltration of ornipressin. Thus the high concentration cannot be recommended for cases with blood pressure dyscrasias. The haemostatic effect was either good in only 60 percent of the patients.

[Artificial blood. Experimental studies on fluorocarbons as chemical blood substitutes]. / I1 sangue artificiale. Ricerche sperimentali sull'uso dei fluorocarbonati come succedanei chimici del sangue.

Fluorocarbonates are organic compounds capable of carrying oxygen and surrendering it to tissues by means of biological sound modalities. Experimentation of an emulsion consisting of perfluorotripropylamine and perfluorodecaline (Fluosol DA 20%) as a blood substitute is reported. Acute (Ht less than 1%) and chronic morphological (Ht = 15%) studies were performed on rats, and a semi-acute biochemical and morphological protocol (Ht = 21%) was experimented in pigs. The first signs of altered cerebral electrical activity occurred at Ht = 2% in the acute experiments, and death due to respiratory arrest took pace at Ht = 0.5%. In the semiacute and chronic experiments, widespread infiltration of fluorocarbonic micelles was noted on histological and electron microscope lung and liver preparations.

[Effects of a partial exchange transfusion with Fluosol DA 20% on healthy pigs]. / Auswirkungen eines teilweisen Blutaustausches mit Fluosol DA 20% auf den intakten Organismus des Schweines.

In 9 animals 500 ml of blood was replaced with 500 ml of Fluosol DA 20%. An average of 19.2 ml per kg body weight of emulsion, i.e. 3.883 gm per kg body weight of fluorocarbons was given. On the eighth day following exchange transfusion the animals were killed and tissue samples taken from liver and lung for electron microscopy and chemical analysis. Biochemical parameters were measured in central venous blood prior to transfusion and on the 2nd, 3rd, 6th and 8th days. One animal died on the sixth day of study, hence only the results obtained from the remaining 8 animals were analysed. On removing the lungs a marked firmness of consistency and failure to collapse was noted. Electron microscopy revealed numerous phagocytic cells packed with foam-like substance, partly occluding the pulmonary capillaries. On chemical analysis a residue of 23.95 mg fluorocarbon per gm of lung tissue was found. Acid-base analysis of central venous blood showed a compensated respiratory acidosis on the 6th and 8th day. The hepatic reticulo-endothelial system was found to be laden with numerous vacuoles, to such a degree that the sinusoids were all practically fully occluded. Neither cell necrosis nor inflammatory reactions were observed.

[Morphology of the pig liver after Fluosol infusion]. / Morphologische Befunde an der Schweineleber nach Fluosol-Infusion.

About 500 ml of blood of young pigs weighing 20...25 mg were replaced by artificial blood substitute "Fluosol-DA 20%". Eight days after exchange the animals were sacrificed and the liver was fixed for electron microscopic investigation. The morphological studies showed Fluosol-droplets in the cytoplasma of parenchymal cells near the bile canaliculi and in the sinusoidal lining cells. Most Fluosol-droplets were found in the endothelial and Kupffer cells which both seemed to be completely filled. The ballooning of these cells often resulted in a partial occlusion of the sinusoids. The sinusoidal lining cells were saturated by Fluosol droplets to such an extent that they seemed to be unable to phagocytize further.