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Introduction: Since conservative antibiotic treatment in uncomplicated appendicitis might not solve the clinical problem definitively, it has to compete with the results of today's laparoscopic appendectomy., Methods: In a county hospital, accommodating also a pediatric department, all cases of appendectomy for suspected appendicitis over 15 years were analyzed retrospectively for the following items: beginning of symptoms, time from admission to surgery, surgical technique as "open," "laparoscopic" or "converted," if perforated at operation and histological confirmation of acute inflammation. Surgical morbidity was detected in distinct categories. To evaluate changes over time, 3 time periods of 5 years each were defined., Results: Resulting in a total of 1,956 cases there were 731 in group I, 633 in group II and 592 in group III within the 3 time periods, respectively. The median age was 17 years. The percentage of perforations was 16.8%. Those patients had - with 47 compared to 27 h - a significantly prolonged time from the beginning of symptoms to admission ( p = 0.0001). The proportion of laparoscopic surgery rose from 83.3 (group I) to 98.3% (group III; p = 0.0001). The median postoperative hospital stay diminished from 4 to 3 days in nonperforated ( p = 0.0001) and from 8 to 7 days in perforated cases ( p = 0.0009). Surgical morbidity was reduced from 4.1% in the first to 1.7% in the third observation period ( p = 0.0144). There were no surgical site infections during the last 5 years., Conclusions: Timely laparoscopic appendectomy in case of suspected appendicitis can be offered with an extraordinary low morbidity. Taking into account the complete solution of the otherwise pending threat, compared to conservative antibiotic treatment, it is safe and definitive., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2020 by S. Karger AG, Basel.)

Objective: Monocytes play an important part in all phases of both humoral and cell-mediated immune responses. In our study, we examined the influence of various drugs used in intensive care (omeprazole, ranitidine, potassium canrenoate, furosemide, clonidine, verapamil, and metamizole) on monocyte chemotaxis in vitro. The 0,1 fold, 1 fold, and 10 fold concentrations, which are detectable in serum after a clinically efficacious bolus injection of the respective drug, were tested., Methods: Using centrifugation, mononuclear cells were isolated from venous blood samples obtained from 10 healthy volunteers. Monocyte chemotaxis was determined by means of a microchemotaxis chamber. N-formyl-methionylleucylphenylalanine served as chemoattractant., Results: Omeprazole, ranitidine, and potassium canrenoate did not influence monocyte chemotaxis. While the 10 fold concentrations of the clinically efficacious serum concentrations of furosemide and verapamil caused a significant inhibition, the 10 fold concentrations of the clinically efficacious serum concentrations of clonidine and metamizole significantly stimulated monocyte motility., Conclusion: Clinically relevant concentrations of the drugs tested did not alter monocyte chemotaxis in vitro. However, 10 fold concentrations of the clinically efficacious serum concentrations, which might occur in vivo due to drug interaction, cumulation, altered elimination, or accidental overdose, caused an inhibition (furosemide, verapamil) or a stimulation (clonidine, metamizole). An in vitro investigation does never permit to jump to clinical conclusions. However, our study gives impulses to conduct intensive care examinations concerning the influence of drugs on monocyte functions particularly since these cells are of great prognostical importance regarding sepsis.

Introduction: In an experimental design the pain reduction effect of acupuncture is studied and compared to the treatment of a classical acupuncture point and a point of the Yamamoto New Scalp Acupuncture (YNSA)., Methods: Experimental pain stimuli (32 per test person) were set in 42 test persons at the upper calcaneus edge and pain reduction was checked intra-individually by using the following variations of treatment: Acupuncture YNSA basis-point D, Acupuncture at the classical point Xiao Chang Shu = Bl 27, Acupuncture at a placebo point of the head, Acupuncture at a placebo point of the gluteal region., Results: Evaluation of the data as well as a statistical investigation using a bi-factoral variance analysis with repeated measurements of 2 respectively 1 factor yielded following results: There are highly significant differences concerning pain reduction through the stimulation of the YNSA basis-point D and the acupuncture at the classical point Bl 27 (p < 0,0007). There are also highly significant differences concerning the verum and the placebo treatment (p < 0,00006). Further hypothesis of controlling the experimental design were tested., Conclusions: On the whole, the investigation shows that there is a marked difference between the verum and placebo treatment as well as a difference between the acupuncture of the YNSA basis-point D and the classical acupuncture point Xiao Chang Shu (Bl 27) with regard to pain reduction induced by experimental stimuli at the calcaneus. These differences are significant.

Background and Objective: Polymorphonuclear leucocytes make a decisive contribution to defence against bacterial infections. In particular, the effects of anaesthetics on non-oxidative bactericidal mechanisms have previously only been superficially examined. Although the influence of anaesthetic agents on oxidative bactericidal activity has been thoroughly examined, our study concentrated on the effect on non-oxidative processes, which appears to have been a neglected field of research., Methods: The effects of methohexital, etomidate, ketamine, fentanyl and morphine on the activity of lysozyme and beta-glucuronidase released from polymorphonuclear leucocytes have been studied in vitro. The activity of lysozyme was determined by recording the changes in the turbidity of a suspension of micrococcus lysodeicticus caused by the enzymatic action of lysozyme. beta-glucuronidase activity was photometrically measured by the enzymatic cleavage of phenolphthalein glucuronic acid., Results: High concentrations of methohexital inhibited lysozyme activity; however, etomidate and morphine caused an increase of beta-glucuronidase activity in therapeutic plasma concentrations. While there was no effect of etomidate on lysozyme activity, all concentrations tested significantly stimulated beta-glucuronidase activity. This result was unexpected because intravenous anaesthetics have previously shown a tendency to suppress polymorphonuclear leucocyte functions. Whereas the inhibition of lysozyme activity by the high concentration of methohexital was no surprise, the increase of beta-glucuronidase activity caused by etomidate, ketamine, fentanyl and morphine was quite unexpected., Conclusions: At present, the underlying mechanism for the increase of beta-glucuronidase activity caused by etomidate, ketamine, fentanyl and morphine is unknown. The fact that there was no influence of these agents on lysozyme activity possibly suggests that the anaesthetic agents have different effects on azurophilic and specific granules. Since in vitro investigations have their limitations, it is too early to draw practical consequences from our study. Moreover, at present it is unclear whether an increase of beta-glucuronidase activity in vivo is an advantage or not. In any case, we think it advisable to perform further investigations on the influence of anaesthetic agents on oxygen-independent bactericidal mechanisms.

The transmissible spongiform encephalopathies (TSE) are known to affect humans and various animals. The bovine spongiform encephalopathy (BSE) and the human Creutzfeldt-Jacob disease (CJD) are among the most notable degenerative disorders caused by prions. Considering the BSE epidemic and the description of a new variant of Creutzfeldt-Jacob disease (nvCJD), which is probably related to bovine spongiform encephalopathy, TSE have recently gained a lot of public attention. Although the causative factors (prions, viruses) are still under discussion, none of the present concepts are explanatory for all aspects of the human CJD. CJD may present as a sporadic, genetic, or infectious illness and there is now considerable concern that bovine prions may have been passed to humans. To exclude transmission of CJD via medical products and instruments, the effectiveness of cleaning, disinfection and sterilization procedures must be firmly established. This manuscript presents an overview to anaesthesiology and intensive care medicine of recommended inactivation procedures and assessed these procedures in the light of the inactivation of prions.

Objective: Polymorphonuclear neutrophile leucocytes (PMNL) play an important role in the defence against bacterial infections. It is known that some anaesthetics are able to disturb PMNL functions. We examined the influence of midazolam and flunitrazepam on the activity of the bactericidal enzymes lysozyme and beta-glucuronidase released from PMNL in vitro., Methods: As described before [4], PMNL were isolated from venous blood samples obtained from 10 healthy male volunteers. PMNL stimulation and measurement of lysozyme and beta-glucuronidase activities were conducted according to the description by Metcalf et al. [5]. The BIOMED-system [8] was used for statistical evaluation., Results: Neither midazolam nor flunitrazepam caused any statistically important alteration of lysozyme activity. However, clinically relevant concentrations of both benzodiazepines significantly enhanced beta-glucuronidase activity. The additives of flunitrazepam did not play any role., Conclusion: Surprisingly enough, midazolam and flunitrazepam increased the activity of beta-glucuronidase released from PMNL in vitro. At present, this result can neither be explained nor can its importance be estimated. On the other hand, the benzodiazepines did not relevantly influence lysozyme activity.

Monocytes play an important role in humoral as well as in cell-mediated immunity. In the present study, the influences of the anti-migraine preparations metoprolol, propranolol, metoclopramide, acetylsalicylic acid, dihydro-ergotamine and sumatriptan on monocyte chemotaxis were examined in vitro. First, mononuclear cells were isolated by centrifugation from venous blood samples obtained from 10 healthy male volunteers. Chemotaxis was determined using a microchemotaxis chamber. While metoprolol, metoclopramide, dihydroergotamine and sumatriptan did not influence monocyte chemotaxis, high doses of propranolol and acetylsalicylic acid caused a significant (p < or = 0.001) inhibition of this important cellular function. Therefore, it is quite possible that both drugs produce adverse immunological effects in vivo in cases of high dosage or obstruction of elimination.

Polymorphonuclear eosinophilic leucocytes (PME) participate in wound healing processes, the inflammatory response, bronchial asthma, allergies and defence against invading parasites. We have examined the effects of thiopental, methohexital, propofol, etomidate and ketamine on PME chemotaxis in vitro. PME were isolated from venous blood samples of 10 healthy volunteers using multi-stage Percoll gradient centrifugation. Eosinophilic chemotaxis was determined using a 48-well microchemotaxis chamber. Thiopental 150 micrograms ml-1 and etomidate 0.32 microgram ml-1 caused significant (P < or = 0.05) inhibition of PME chemotaxis. We conclude that thiopental and etomidate may have an adverse influence on wound healing processes and parasitic diseases. Further studies are recommended.

Monocytes play a very important part in humoral as well as in cell-mediated immunity. At present, however, the knowledge of the influence of anaesthetic agents on the functions of monocytes is limited. In the present study, the effects of thiopentone, methohexitone, ketamine, midazolam, droperidol, propofol, etomidate, and fentanyl on monocyte chemotaxis were examined in vitro using a 48-well microchemotaxis chamber. Clinically relevant concentrations of ketamine, midazolam, and droperidol significantly (P < or = 0.05) inhibited chemotaxis. For that reason, it is possible that these anaesthetics impair the immunological system in vivo. This possibility should be further examined.

Polymorphonuclear leucocytes (PMNL) are an essential contribution to protection from bacterial infection. We have examined the effects of thiopentone, etomidate, ketamine and flunitrazepam on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro with fluorescence microscopy. All anaesthetic agents significantly inhibited both phagocytosis and bactericidal activity. The additives in the commercial preparations may have contributed to the suppression.

Polymorphonuclear leukocytes (PMNL) make an outstanding contribution to the defence against invading bacteria. We studied the effects of midazolam, droperidol, fentanyl, and alfentanil on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro. Using a method described by Eggleton et al., PMNL were isolated from venous blood samples obtained from ten volunteers. The fluorescence microscopic method mentioned by Bellinati-Pires et al. was used to examine phagocytosis and killing. Whereas both midazolam and droperidol caused a significant inhibition of phagocytosis as well as bactericidal activity, fentanyl and alfentanil did not influence these PMNL functions. In order to find out whether midazolam and droperidol are able to intensify perioperative bacterial infections in vivo as well, additional clinical studies should be conducted.

Polymorphonuclear leucocytes (PMNL) are an essential component of the defence system against invading bacteria. There is evidence that some anaesthetics are able to suppress PMNL functions, promoting, perhaps, perioperative infection. We studied the effects of thiopentone, etomidate, ketamine, and midazolam on the generation of bactericidal agents (superoxide anion, hydrogen peroxide, and myeloperoxidase) by PMNL in vitro. Thiopentone inhibited superoxide anion (P < or = 0.01) as well as hydrogen peroxide production (P < or = 0.001). However, there was no statistically significant effect on myeloperoxidase release. Neither etomidate nor ketamine influenced the PMNL functions tested to any extent. Midazolam suppressed superoxide anion generation (P < or = 0.01) but only if a concentration far beyond clinical relevance was used.

Polymorphonuclear leukocytes (PMNL) are important components of the immunological defence system which protects the human organism from invading bacteria. Using a fluorescence microscopic method, we examined the influence of propofol and its solvent intralipid on phagocytosis and killing of Staphylococcus aureus and Escherichia coli by PMNL in vitro. Propofol inhibited (P < or = 0.001) phagocytosis of Staphylococcus aureus as well as Escherichia coli. Killing of Staphylococcus aureus (P < or = 0.001) and of Escherichia coli (P < or = 0.01) was suppressed. Intralipid, by itself, impaired phagocytosis of Escherichia coli (P < or = 0.05). Apart from that, intralipid produced no relevant effects. Additional clinical studies regarding the influence of propofol on PMNL function are recommended.

Polymorphonuclear leukocytes (PMNL) play a vital role in the defence against invading bacteria. It is known that some anaesthetics inhibit PMNL function and, thus, possibly enhance perioperative infection. We investigated the effect of methohexitone, flunitrazepam, and droperidol on three bactericidal PMNL functions, i.e., superoxide anion production, hydrogen peroxide generation, and activity of released myeloperoxidase, in vitro. Approved photometrical assays were used. Superoxide anion was measured by the reduction of cytochrome C, hydrogen peroxide by the horse radish peroxidase catalysed oxidation of phenol red, and myeloperoxidase by the turnover of 2,2'-azino-di(3-ethylbenzthiazoline) sulfonic acid. Methohexitone (P < or = 0.001) and flunitrazepam (P < or = 0.01) inhibited superoxide anion production, and methohexitone (P < or = 0.01) reduced hydrogen peroxide generation but only at concentrations beyond clinical relevance. Droperidol did not cause any alteration of the PMNL functions tested. Consequently, it seems unlikely that the usual doses of methohexitone, flunitrazepam, or droperidol promote bacterial infections in vivo by impairing the activity of myeloperoxidase or by inhibiting the generation of superoxide anion or hydrogen peroxide.

Polymorphonuclear leukocytes (PMNL) play an important part in protecting against invading bacteria. It is known that some anaesthetics may impair PMNL functions, thus possibly promoting infection. We investigated the effect of fentanyl and alfentanil on superoxide anion production, hydrogen peroxide generation, and activity of released myeloperoxidase in vitro. However, the two opioids did not have any significant influence on the tested PMNL functions.

Infection remains a major cause of morbidity and mortality in intensive care medicine. The increased susceptibility of the severely injured patient to sepsis and consecutive multiorgan failure has been attributed to abnormalities in cell-mediated immunity. The purpose of our study was to determine changes in the pattern of lymphocyte subpopulations in severely injured patients and to relate these changes to any development of sepsis and to outcome (indirect immunofluorescence with monoclonal antibodies). During 14 months we investigated 28 patients (ages 15-65 years) suffering from severe multisystem trauma (22 cases) or diffuse peritonitis (6 cases), 6 of whom (21.4%) developed sepsis and multiorgan failure; 4 of these 6 septic patients died. According to the clinical data, patients developed sepsis between the 3rd and 6th days after trauma. We therefore defined days 1-3 as the preseptic phase, days 3-6 as the phase of sepsis development, and days 4-10 as the phase of septic disease. In the preseptic phase there was no statistically significant difference in the pattern of the eight lymphocyte subpopulations measured between patients who later developed sepsis and those who did not. During the phase of sepsis development, however, the patients who did develop sepsis showed significantly reduced numbers of CD2-, CD8-, and CD20-positive cells (P = 0.0003; P = 0.009; P = 0.012). The number of helper cells (CD4) was also decreased, but the difference between the two groups failed to reach statistical significance (P = 0.08).(ABSTRACT TRUNCATED AT 250 WORDS)

Knowledge of the actual concentrations of local anesthetic administered by various techniques is essential requisite when undesirable side effects and possible toxicity of a substance are to be evaluated. Therefore, numerous studies of plasma concentrations have been presented, which were carried out with the additional purpose of analyzing the kinetics of different local anesthetics with respect to limiting-value concentrations in the organism. Despite a sufficient degree of precision in the analysis of amide local anesthetics, it is uncertain whether the results of the different studies are comparable, because blood samples have been taken variously from peripheral veins, central veins or arteries. In the present study changes in bupivacaine concentrations were monitored by means of a standardized method consisting in simultaneous sampling of blood in peripheral veins, central veins and arteries. METHODS. Each of 12 patients undergoing orthopedic hip surgery received average 17 ml bupivacaine (0.75%) via peridural lumbar catheter. After the administration of bupivacaine, blood samples were taken simultaneously from peripheral veins, central veins and arteries at 1, 3, 5, 10, 15, 30, 45, 60, and 90 min after injection. Placement of an arterial cannula and central venous catheter was indicated in all patients (hip-joint revision arthroplasty). Quantitative analysis of bupivacaine concentration was carried out by means of high-pressure liquid chromatography (HPLC). All patients had given their informed consent. RESULTS. All patients showed a rapid increase in bupivacaine concentration in the central venous blood within the first few minutes after administration, the maximum being reached between 3 and 10 min after. A similar course was observed with arterial plasma concentrations; absolute values, however, were an average of 10-20% lower at 15 min following administration. Bupivacaine concentrations in peripheral veins rose more slowly and reached a maximum between 15 and 30 min. At 30 min after peridural application the concentration curves in blood from all three sites were similar. DISCUSSION. In earlier studies the influence of the site of blood sampling has often been underestimated. According to our results, central venous and arterial plasma concentrations correspond closely at all times following peridural application. The observed uniform differences in concentrations at the various sites of sampling can be explained by the fact that pulmonary uptake of local anesthetics causes the lower arterial levels. Especially in the early phase of resorption after administration of local anesthetics, the concentration in peripheral blood does not seem to be representative, because an equilibrium is not established between arterial and central venous blood until 30 min after administration at the earliest. In our opinion the peripheral venous concentrations are unreliable, particularly in the early phases, for the evaluation of unwanted effects or toxicity of local anesthetics, because the initial low values and the delayed increase in these could lead to a false sense of security.

Pharmacokinetics of mezlocillin (70 mg/kg as an infusion) were investigated in 8 patients with multiorgan failure undergoing continuous veno-venous haemofiltration (CVVH) due to acute renal failure (HF-group) in comparison to 8 intensive care patients with an uneffected renal system (control group). Mezlocillin concentration were studied in blood, ultrafiltrate and urine (control group). Elimination of mezlocillin was prolonged in the HF-group with a t1/2 of 170 min in comparison to 109 min in the control patients. No relevant absorption at the haemofilter membrane could be observed. With regard to our results a dose reduction and intermittend application of mezlocillin is suggested; in addition, monitoring of drug levels in critically ill patients becomes of increasing interest, especially during haemofiltration.

The influence of clinically relevant concentrations of thiopentone sodium, methohexitone, and etomidate on polymorphonuclear neutrophilic granulocyte (PMN) adherence was investigated in vitro by using nylon fibre columns. The three induction agents produced dose-dependently a significant (p less than 0.01) reduction in adherence. This effect is possibly related to increased risk of postoperative bacterial infection. Further studies on this problem are recommended.

Risk factors related to increased mortality were determined on the basis of 329 aortocoronary bypass operations. They were: (1) emergency surgery, (2) poor left ventricular function, (3) reoperation, and (4) pulmonary hypertension. Angina pectoris, recent myocardial infarction, age over 65 years, obesity, significant systemic disturbances, smoking, arterial hypertension, and sex were without effect.

Somatosensory evoked potentials (SEP) after median nerve stimulation were recorded in 40 patients during infusion of either 15 mg/kg bw thiopentone or 1 mg/kg bw etomidate (n = 10) within 15 min and after 0.3 mg/kg bw etomidate (n = 20). Marked alterations of SEP waveforms and changes in latencies were observed in all patients. Central conduction time (CCT) was significantly correlated to plasma thiopentone concentration. Infusion of high doses of thiopentone and etomidate was followed by a complete loss of middle and long latency components. Amplitude of the primary cortical SEP N20 was found to be unchanged after thiopentone and to be increased after etomidate, indicating the synchronizing properties of this drug. A pronounced increase in SEP latencies and CCT and waveform alterations have to be considered during hypnotic drug administration in intensive care medicine and intraoperatively.

The prosthetic supply of the hip-joint may be accompanied by the problem of venous air embolism. By including 53 orthopaedic patients having undergone total hip replacement, the influence of bone-cement as well as of the different anaesthetic techniques on the frequency of embolic phenomenons was investigated. Embolism was determined as an abrupt decrease (greater than 5 mmHg) in the end-tidal pCO2. Venous embolism often occurred with cemented endoprostheses in contrast to non-cement implantations. Patients with general anaesthesia presented more often with venous air embolism than patients with epidural anaesthesia. This might be explained by an expanding effect of nitrous oxide on air bubbles entering the vascular bed under the implantation of the shaft-prostheses. Our data stress the importance of continuous monitoring of end-tidal pCO2 for early discovery of lung embolism.

The influence of clinically relevant concentrations of fentanyl, alfentanil, morphine, pethidine, and buprenorphine on polymorphonuclear neutrophilic granulocyte (PMN) adherence was investigated in vitro by using nylon fibre columns. Since none of the drugs produced any significant (p less than 0.05) change of adherence, no evidence of opioid mediated increased risk of postoperative bacterial infection could be found.

The general opinion on epidural anesthesia in obstetrics may be adversely affected by recent public controversies about the mother's situation during childbirth in hospital, which nowadays is often considered to be a highly technological, impersonal, or "unnatural" procedure. This assumption led us to conduct an inquiry on maternal assessment of obstetric epidural anesthesia and its relation to the clinical and social history. The study included 113 parturients, who received epidural anesthesia (on-demand epidural injections of bupivacaine 0.25%) for vaginal delivery. Mothers were asked to answer certain questions about this regimen (e.g. analgetic efficacy; difficulties in deciding on this method; recommendations to other parturients; opinion of the role of epidural anesthesia in obstetrics; choice of analgesic regimen for future childbirth) 1 day after delivery and 2 months later. Additional social and historical factors (e.g. education; profession; family status; preceding pregnancy, childbirth or abortion; complications during pregnancy or childbirth; duration of parturition) were used to reveal relevant statistical correlations. Sixty-five percent of the patients considered pain relief by epidural anesthesia as "good" or even "very good" during the first inquiry immediately after childbirth. Women who had undergone prior interruptions of pregnancy were less satisfied, probably because of their rather ambiguous attitude towards motherhood. With regard to the choice of analgesic regimen for future childbirth (50% of the patients had made a definite decision to have epidural anesthesia under this condition), those women were especially reserved who had suffered from complications during pregnancy and disapproved of it in the future.(ABSTRACT TRUNCATED AT 250 WORDS)

In patients with cancer pain treated by continuous epidural opiate infusion (4.5-24 mg morphine per day) via implanted or portable pumps (n = 40) plasma levels of morphine were determined during the postoperative period and during regular refill of the pump systems. Concentrations were between 2.6 and 18.8 ng/ml depending on daily dosage and body weight. There were no signs of accumulation. Concentrations in lumbar CSF measured in some of the patients were 15-20 higher but decreased by 10-20% (in relation to daily dosage) in the course of long-term treatment. This may be induced by reduction in permeability of the dura due to fibrosis within the epidural space after chronicle catheterization. Cervical CSF concentrations (during chordotomy) were about 1/6 to 1/7 of the corresponding lumbar CSF levels. It may be assumed that epidural opiate infusion in spite of low blood levels is accompanied by relevant cerebral opiate actions.

After injection of etomidate during surgery for herniation of an intervertebral disk an anaphylactoid reaction occurred. Generalized erythema, severe urticaria, and rise in heart rate and blood pressure drop were observed. After treatment with an antihistaminic and a corticosteroid the phenomenons completely disappeared within 45 minutes.

Alfentanil mask anaesthesia was performed in 63 patients undergoing termination of pregnancy or curettage. Three different types of premedication were used: a) pethidine, promethazine, and atropine; b) diazepam and atropine; c) atropine. The patients were ventilated either with nitrous oxide and oxygen or with halothane and oxygen. Halothane reduced the frequency of muscular rigidity (32%; N2O 75%), postoperative sickness, and vomiting (23%; N2O 50%). On the other hand, patients regained consciousness earlier if nitrous oxide was used. Premedication a) also reduced the frequency of nausea and emesis (21%; other premedications 63%).-Alfentanil intubation anaesthesia was performed in 52 patients undergoing laparoscopy. Premedication and inhalation anaesthetic varied as described above in the group with mask anaesthesia. Muscular rigidity did not occur, and nausea/emesis were rare events (8%). Halothane prolonged the recovery phase of consciousness and respiration. Premedication a) also resulted in respiratory depression.

The influence of midazolam and ketamine on polymorphonuclear neutrophil granulocyte (PMN) adherence was investigated in vitro by using nylon fiber columns. Both a concentration of 1.0 microgram midazolam/ml blood and 0.2 microgram/ml caused a reduction of adherence. This decrease was significant (p less than 0.05) in the case of the higher dosage. The two concentrations of ketamine used (1.3 micrograms/ml resp. 0.5 microgram/ml) produced a significant reduction of adherence too. Thus both anesthetic agents are able to impair PMN function in vitro dose-dependently. This feature is possibly related to increased risk of postoperative bacterial infection. Further studies concerning this problem should be conducted.

Spectral analysis with the compressed spectral array display (CSA) and calculation of spectral edge frequency (SEF) was performed in 43 cases undergoing endarterectomy of the carotid bifurcation. New neurologic deficit appeared in 2 patients (= 4.6%). One of them died postoperatively (= 2.3%), the other suffered from permanent paralysis of the hand. Another 9 patients showed loss of high frequency activity (= decrease in SEF) without a new deficit in the postoperative period. A significant EEG event was defined as a decrease in SEF after carotid cross clamping for at least 5 min. Fisher's exact probability test revealed a close correlation between these EEG events and neurologic outcome. The sensitivity of the test, which was calculated on true positive and false negative events, was 100%, the specificity, based on true negative and false positive events, was 76%. The predictability of the test, based on all EEG events, was 18%; respectively 40% when calculated on significant events.

A demand-controlled alfentanil bolus technique, which proved to be a safe and easy-to-handle method in 22 neurosurgical operations of mean and longer duration, is described. In the case of these not very painful procedures the use of more complicated time-controlled bolus or infusion techniques does not seem to be necessary.

Infection is still an important problem following surgery. Polymorphonuclear neutrophil granulocytes (PMN) play a vital role in host defenses against invading bacteria; thus, adverse effects on PMN caused by anesthetic agents are of general interest. In this study, we examined the influence of pancuronium bromide on PMN adherence in vitro. Heparinized venous blood samples were obtained from 18 healthy male adult donors. Each specimen was divided. One part was used to determine the adherence of untreated PMN, while pancuronium bromide was added to the other. Two concentrations (1.3 or 0.5 micrograms relaxant/ml blood) were tested. PMN adherence was studied using nylon fiber columns as described by MacGregor et al. Both concentrations of pancuronium bromide caused an inhibition of adherence, which was significant in the case of the higher dosage (p less than 0.05). There is a direct correlation between the intensity of PMN adherence and the extent of granulocyte delivery to sites of inflammation. Therefore, it seems possible that clinical concentrations of pancuronium bromide may be able to increase the risk of developing bacterial infections. Further studies concerning this problem should be conducted.

44 patients undergoing comparable gynaecological operations received either halothane- modified neuroleptanaesthesia or a combination of epidural and NLA. Monoclonal antibodies were used to determine 8 different lymphocyte subpopulations in blood samples drawn before and after anaesthesia and on the first postoperative day. Cell populations were counted by fluorescent microscopy. Halothane anaesthesia produced both a depression of T-cells (72.67% preoperatively to 52.79% postoperatively) and of the helper/suppressor ratio (1.46 to 1.10); meanwhile activated T-cells increased from 2.33% to 6.83%. After neuroleptanaesthesia as well as after halothane the HLA-DR positive cells decreased (21.05% to 19.29%; 25.22% to 20.29%). The B-cell fraction was elevated from 2.33% to 6.83% following combined anaesthesia. The potential of the anaesthetics to produce subsequent alterations in host defense is discussed.

Methodological considerations and different stimulation techniques of visual evoked potentials (VEP) are described. VEP can provide information about neurological function during anaesthesia, surgery and in the unconscious patient after head injury. The feasibility of the method for intraoperative monitoring in neuro- and cardiac surgery and the influence of general anaesthetics and other contributing factors such as temperature, paCO2, pO2, part are discussed.