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H Sonntag

Publications and source records attributed to H Sonntag.

At least 37 records · Page 2Linked to original sources
PubMed1999

Patterns of cannabis use, abuse and dependence over time: incidence, progression and stability in a sample of 1228 adolescents.

AIMS: To present data on the incidence of cannabis use at follow-up, and its progression, stability, abuse and dependence in a representative sample of adolescents (N = 1228), aged 14-17 years at "baseline"--the outset of the study--in Munich, Germany. DESIGN: The study employed a prospective longitudinal design using a representative population sample. The mean follow-up time was 19.7 months. The Composite International Diagnostic Interview (M-CIDI) was used to assess patterns of use, abuse and dependence according to DSM-IV criteria. FINDINGS: (1) In our sample, 34.8% of males and 30.2% of females had tried cannabinoids at least once. (2) Of those who used cannabis repeatedly (two or four times) at baseline, 26.1% stopped using by follow-up; the majority went on to regular use in the follow-up period. Similarly, only 17.7% of the regular users at the outset stopped using cannabis completely; 74.2% continued their pattern of regular use. Thus, the higher the baseline use pattern, the higher was the probability of continued or heavier use during follow-up. (3) Although the cumulative life-time incidence for DSM-IV cannabis abuse (3.5%) in this age group was low, it is noteworthy that complete diagnostic remissions were relatively rare (31.7% for dependence, 41.1% for abuse). (4) There was considerable concurrent use of other drugs. CONCLUSIONS: Cannabis use was almost as widespread in this sample of adolescents in Germany as in similar age groups in metropolitan areas of North America. There was a relatively low spontaneous remission rate among regular and repeated users. Cannabis use in adolescence appears to be less transient than many people would believe.

Adolescent↗
PubMed1999

Covariates of cannabis use progression in a representative population sample of adolescents: a prospective examination of vulnerability and risk factors.

UNLABELLED: AIMS/DESIGN: This study reports findings concerning risk factors for first, "repeated" and "regular" use of cannabis in respondents (N = 1228) who were aged 14-17 years at the outset (i.e. at "baseline") as part of a longitudinal prospective community study (EDSP). Risk factors were assessed at baseline or by separate interviews with the respondents' parents. Cumulative life-time cannabis use was the main outcome measure in this study--assessed by information from both the baseline and the follow-up investigation at an average of 19.7 months later. A cumulative logistic regression model was used to estimate associations. FINDINGS: Using seven of a total of 25 variables examined, the final model classified 72.1% of respondents correctly. Family history of substance use disorders, self-esteem and competence, unconditional commitment to not using drugs, immediate availability of drugs, peer group drug use and previous history of nicotine dependence and alcohol use disorders all contributed significantly to the final model, predicting the progression to cannabis use from "no use", to "one time only", "repeated use", and "regular use". CONCLUSION: In addition to well-documented risk factors such as peer group pressure, availability, low self-esteem and competence, findings suggest that family history and prior experiences with legal drugs play a significant role in the early development of cannabis consumption in teenagers.

Adolescent↗
PubMed1999

Changes in central venous pressure and pulmonary capillary wedge pressure do not indicate changes in right and left heart volume in patients undergoing coronary artery bypass surgery.

The value of pulmonary artery catheterization is a matter for discussion. Previous studies suggest that direct measurements of intravascular volume distribution and cardiac volume indices may be of greater relevance than central venous and pulmonary capillary wedge pressure. We therefore used a thermo-dye dilution technique for the quantification of central blood volume, right ventricular end-diastolic volume and left heart volume in patients undergoing coronary artery bypass surgery. Measurements were performed after the induction of anaesthesia as well as 1, 6 and 24 h after surgery. Central venous pressure was significantly increased at 1 and 6 h, whereas right ventricular end-diastolic volume was increased only at 6 h post-operatively. Pulmonary capillary wedge pressure showed a tendency to increase whereas left heart and central blood volume decreased significantly after surgery. The results of the present study suggest that changes in cardiac filling pressure do not indicate changes in indices of cardiac volume in patients after coronary bypass surgery.

Blood Volume↗
PubMed1999

Volatile anaesthetics and the atmosphere: atmospheric lifetimes and atmospheric effects of halothane, enflurane, isoflurane, desflurane and sevoflurane.

The atmospheric lifetimes of the halogenated anaesthetics halothane, enflurane, isoflurane, desflurane and sevoflurane with respect to reaction with the hydroxyl radical (OH.) and UV photolysis have been determined from observations of OH. reaction kinetics and UV absorption spectra. Rate coefficients for the reaction with OH radicals for all halogenated anaesthetics investigated ranged from 0.44 to 2.7 x 10(-14) cm3 molec-1 s-1. Halothane, enflurane and isoflurane showed distinct UV absorption in the range 200-350 nm. In contrast, no absorption in this wavelength range was detected for desflurane or sevoflurane. The total atmospheric lifetimes, as derived from both OH. reactivity and photolysis, were 4.0-21.4 yr. It has been calculated that up to 20% of anaesthetics enter the stratosphere. As a result of chlorine and bromine content, the ozone depletion potential (ODP) relative to chlorofluorocarbon CFC-11 varies between 0 and 1.56, leading to a contribution to the total ozone depletion in the stratosphere of approximately 1% for halothane and 0.02% for enflurane and isoflurane. Estimates of the greenhouse warming potential (GWP) relative to CFC-12 yield values of 0.02-0.14, resulting in a relative contribution to global warming of all volatile anaesthetics of approximately 0.03%. The stratospheric impact of halothane, isoflurane and enflurane and their influence on ozone depletion is of increasing importance because of decreasing chlorofluorocarbons globally. However, the influence of volatile anaesthetics on greenhouse warming is small.

Air Pollutants↗
PubMed1999

Effects of one minimum alveolar anesthetic concentration sevoflurane on cerebral metabolism, blood flow, and CO2 reactivity in cardiac patients.

UNLABELLED: We investigated the cerebral hemodynamic effects of 1 minimum alveolar anesthetic concentration (MAC) sevoflurane anesthesia in nine male patients scheduled for elective coronary bypass grafting. For measurement of cerebral blood flow (CBF), a modified Kety-Schmidt saturation technique was used with argon as an inert tracer gas. Measurements of CBF were performed before the induction of anesthesia and 30 min after induction under normocapnic, hypocapnic, and hypercapnic conditions. Compared with the awake state under normocapnic conditions, sevoflurane reduced the mean cerebral metabolic rate of oxygen by 47% and the mean cerebral metabolic rate of glucose by 39%. Concomitantly, CBF was reduced by 38%, although mean arterial pressure was kept constant. Significant changes in jugular venous oxygen saturation were absent. Hypocapnia and hypercapnia caused a 51% decrease and a 58% increase in CBF, respectively. These changes in CBF caused by variation of Paco2 indicate that cerebrovascular CO2 reactivity persists during 1 MAC sevoflurane anesthesia. IMPLICATIONS: We used a modified Kety-Schmidt saturation technique to investigate the effects of 1 minimum alveolar anesthetic concentration (MAC) sevoflurane on cerebral blood flow, metabolism, and CO2 reactivity in cardiac patients. We found that the global cerebral blood flow and global cerebral metabolic rate of oxygen remained coupled and that cerebrovascular CO2 reactivity is not impaired by the administration of 1 MAC sevoflurane.

Aged↗
PubMed1999

[Does method of anesthesia modify postoperative ischemia incidence? A study of patients after aortocoronary bypass operations].

In the postoperative period after coronary artery bypass graft surgery, the physician's enhanced attention should be focused on the incidence of myocardial ischaemia. The increased stress in the awakening patient as well as the return of autonomous reflexes can be the cause of imbalances in myocardial oxygen supply and uptake. Therefore, a probable influence of the pharmacologic profile of the intraoperatively applied anaesthetics on the incidence of postoperative myocardial ischaemia is of importance for adapting therapy on ICU to minimize any ischaemic risk. After approval by the ethics committee, a prospective randomized study was performed in 40 male patients who underwent coronary artery bypass graft surgery. The aim of the study was to compare balanced anaesthetic techniques performed with fentanyl and halothane, isoflurane and enflurane, respectively, with total intravenous anaesthesia performed with fentanyl and midazolam. An index to classify detection of ischaemia into three categories (ischaemia, probable ischaemia, no ischaemia) was established, based on measurements of myocardial lactate extraction and ST-segment analysis. Simultaneously, measurements of haemodynamic parameters and serum concentrations of catecholamines and intraoperatively applied anaesthetics were taken. In 8% of all measurements (30% of all patients) ischaemia was detected in the observation period and in 37% of all measurements (72.5% of all patients) probable ischaemia was detected. No significant difference was found concerning the incidence of myocardial ischaemia between all groups. The results of this investigation indicate that the application of inhalational anaesthetics for maintaining anaesthesia in coronary artery bypass graft surgery does not increase the risk of postoperative myocardial ischaemia.

Adult↗
PubMed1998

Effects of 1 MAC desflurane on cerebral metabolism, blood flow and carbon dioxide reactivity in humans.

We investigated the cerebral haemodynamic effects of 1 MAC desflurane anaesthesia in nine male patients scheduled for elective coronary bypass grafting. For the measurement of cerebral blood flow (CBF) a modified Kety-Schmidt saturation technique with argon as inert tracer gas was used. Measurements of CBF were made before induction of anaesthesia and 30 min after induction under normocapnic, hypocapnic and hypercapnic conditions in sequence. Changes in mean arterial pressure after induction of anaesthesia and during the course of the study were minimized using norepinephrine infusion. In comparison with the awake state under normocapnic conditions, desflurane reduced mean cerebral metabolic rate of oxygen (CMRO2) by 51% and mean cerebral metabolic rate of glucose (CMRglc) by 35%. Concomitantly, CBF was significantly reduced by 22%; jugular venous oxygen saturation (SjvO2) increased from 58 to 74%. Hypo- and hypercapnia caused a 22% decrease and a 178% increase in CBF, respectively. These findings may be interpreted as the result of two opposing mechanisms: cerebral vasoconstriction induced by a reduction of cerebral metabolism and a direct vasodilator effect of desflurane. CBF alterations under variation of PaCO2 indicate that cerebrovascular carbon dioxide reactivity is not impaired by application of 1 MAC desflurane.

Aged↗
PubMed1998

Effects of respiratory alkalosis and acidosis on myocardial blood flow and metabolism in patients with coronary artery disease.

BACKGROUND: Variation of the arterial carbon dioxide partial pressure (PaCO2) is not uncommon in anesthetic practice. However, little is known about the myocardial consequences of respiratory alkalosis and acidosis, particularly in patients with coronary artery disease. The aim of the current study was to investigate the effects of variation in PaCO2 on myocardial blood flow (MBF), metabolism, and systemic hemodynamics in patients before elective coronary artery bypass graft surgery. METHODS: In 10 male anesthetized patients, measurements of MBF, myocardial contractility, metabolism, and systemic hemodynamics were made in a randomized sequence at PaCO2 levels of 30, 40, and 50 mmHg, respectively. The MBF was measured using the Kety-Schmidt technique with argon as a tracer. End-diastolic left ventricular pressure and the maximal increase of left ventricular pressure were assessed using a manometer-tipped catheter. RESULTS: The cardiac index significantly changed with varying PaCO2 levels (hypocapnia, - 9%; hypercapnia, 13%). This reaction was associated with inverse changes in systemic vascular resistance index levels. The MBF significantly increased by 15% during hypercapnia, whereas no change was found during hypocapnia. Myocardial oxygen and glucose uptake and the maximal increase of left ventricular pressure were not affected by varying PaCO2 levels. CONCLUSIONS: In anesthetized patients with coronary artery disease, short-term variations in PaCO2 have significant effects on MBF but do not influence global myocardial oxygen and glucose uptake. Changes in systemic hemodynamics associated with respiratory alkalosis and acidosis are caused by changes in systemic vascular resistance rather than by alterations in myocardial contractility.

Acidosis, Respiratory↗
PubMed1998

Influence of arterial carbon dioxide tension on systemic vascular resistance in patients undergoing cardiopulmonary bypass.

BACKGROUND: The effects of induced hypothermia in cardiac surgical patients are not yet fully understood. Despite numerous studies on the effects of acid-base management on organ blood flow, only little information is available on the effects of alpha-stat versus pH-stat management on systemic haemodynamics. We therefore compared the effect of alpha-stat and pH-stat acid-base management on systemic haemodynamics in a prospective, controlled, cross-over study. METHODS: Twenty patients undergoing coronary artery bypass surgery were included in the study. Cardiac output was measured by thermodilution. Cardiac index and systemic vascular resistance were calculated according to standard formulae. Measurements were performed under hypo- and hypercapnia after induction of anaesthesia. Measurements were repeated at the end of two 30-min periods of pH-stat and alpha-stat acid-base management, respectively. RESULTS: Systemic vascular resistance at the lower PaCO2-levels (hypocapnia and alpha-stat, respectively) was significantly higher than those at the higher level (hypercania and pH-stat, respectively). The periods of different PaCO2-levels were comparable with respect to haematocrit, blood viscosity and temperature. Systemic vascular resistance was not significantly different from the control period. CONCLUSIONS: This study demonstrates that during hypothermic cardiopulmonary bypass, systemic vascular resistance under alpha-stat acid-base management is higher than under pH-stat management. As obvious from measurements during the control period, this finding can be completely explained by the difference in PaCO2.

Aged↗
PubMed1997

Acute affect of mitral calve replacement on extravascular lung water in patients receiving colloid or crystalloid priming of cardiopulmonary bypass.

Despite numerous studies on extravascular lung water (EVLW) in patients undergoing coronary artery bypass surgery, few data are available on the perioperative time course of EVLW in patients undergoing mitral valve replacement for mitral valve insufficiency (MVI). We have investigated 26 patients undergoing elective mitral valve replacement in order to determine the influence of the preoperative degree of mitral valve insufficiency (degree III or IV) and the effect of different priming solutions for cardiopulmonary bypass. Crystalloid priming with Ringer's lactate was compared with human albumin priming solution. Measurement of EVLW was performed using the thermo-dye dilution technique, before and 1, 6 and 24 h after surgery. Before operation, EVLW is increased significantly in patients with MVI degree IV (MVI-degree IV) compared with patients with degree III (MVI-degree III) and patients undergoing coronary artery bypass surgery. During the postoperative time course a significant decrease in EVLW was observed in patients with MVI-degree IV whereas in patients with MVI-degree III the amount of EVLW did not change. However, compared with patients undergoing coronary artery bypass surgery, EVLW remained above normal in both groups. There was no interaction between the type of priming solution and the postoperative time course of EVLW, and no differences in respiratory variables or duration of mechanical ventilation were observed between groups.

Adult↗
PubMed1996

[Measurement of human cerebrovascular circulation. Comparison of Kety-Schmidt technique with the intravenous 133-xenon clearance technique].

UNLABELLED: In this study cerebral blood flow (CBF) was simultaneously measured with the Kety-Schmidt method and the intravenous 133Xe clearance technique. CBF, cerebral metabolic rate of oxygen (CMRO2), and CO2 reactivity of CBF were compared under fentanyl-midazolam anaesthesia and varying paCO2 levels. METHODS: Thirteen male patients were studied before they underwent coronary artery bypass surgery. For measurement of CBF with the Kety-Schmidt inert gas saturation technique, argon was used as indicator instead of nitrous oxide, because argon is less soluble in water and lipid such that arterial and hence organ saturation is attained earlier. Wash-in periods of 10 min were used for all measurements. For measurement of CBF with the intravenous xenon method 10 scintillation detectors placed lateral to the skull and an air detector for calculation of tracer recirculation were used. 10-15 mCi of 133Xe dissolved in physiological saline was injected via a peripheral i.v. cannula. For comparison with the Kety-Schmidt technique CBF15-values representing the flow of the grey and white matter were chosen. CBF was measured simultaneously with both methods under normocapnic (paCO2 43 +/- 3 mmHg), hypocapnic (paCO2 31 +/- 3 mmHg), and under hypercapnic (paCO2 54 +/- 4 mmHg) conditions. RESULTS: All CBF15 values obtained with the intravenous xenon method were significantly lower than the corresponding CBF-values measured with the Kety-Schmidt technique: by 36% under normocapnic, 23% under hypocapnic, and 39% under hypercapnic conditions, respectively. Hence, CMRO2 values calculated from CBF values obtained with the xenon method were reduced to about the same degree as those derived from CBF values measured with the Kety-Schmidt technique. There was no significant correlation between the CBF values of either method (y = 1.82x-8.58,r = 0.76 P = 0.357). Non-linear curve-fitting procedures yielded exponential CBF-paCO2 relationships for both methods, although the relative carbon dioxide reactivity was higher with the Kety-Schmidt technique than with the xenon method (y = 8.14 e0.039x vs y = 10,75 e0.023x). CONCLUSIONS: Most probably due to contamination with radioactivity from slowly perfused extracerebral tissues the intravenous 133Xe-clearance technique underestimates CBF, CMRO2, and cerebrovascular CO2 reactivity, at least when CBF15 values are used as flow parameters.

Adjuvants, Anesthesia↗
PubMed1996

[The effect of nitroglycerin on cerebrovascular circulation, cerebrovascular CO2-reactivity and blood flow rate in basal cerebral arteries].

UNLABELLED: The cerebral haemodynamic effects of vasodilators are of clinical interest because a decrease in mean arterial pressure (MAP) might alter global cerebral blood flow (CBF). Luxury perfusion of the brain, contrast, might be unfavourable in patients with reduced intracranial compliance. Despite the widespread use of nitroglycerine (NTG), little is known about the cerebral haemodynamic consequence of NTG infusions in humans. This prospective, controlled study was designed: (1) to investigate the effects of NTG on CBF and cerebrovascular CO2 reactivity and (2) to compare reference measurements of global CBF with transcranial Doppler monitoring (TCD) of middle cerebral artery flow velocity (VMCA). METHODS: With ethical committee approval and informed patient consent, we investigated ten patients undergoing coronary artery bypass surgery. Measurements were performed under fentanyl/midazolam anaesthesia prior to the start of the operation. First, during a baseline period, ventilation was changed in a random sequence to achieve two different levels of arterial PCO2 (30 and 50 mmHg, respectively). Consequently, measurements were repeated during i.v. infusion of 1.5.micrograms.kg-1.min-1 NTG at identifical PCO2 levels. Measurements of CBF were performed by the Kety-Schmidt technique with argon as an indicator. Simultaneously, VMCA was recorded by use of a 2-Mhz transcranial Doppler system. Cerebral perfusion pressure (CPP) was calculated from the difference between MAP and jugular bulb pressure. Statistical analysis was performed by two-way analysis of variance using a repeated-measures design to assess the effects of NTG application and respiratory changes, respectively. RESULTS: During NTG infusion, CPP decreased slightly by 15-17%. Because of a reduction in cerebrovascular resistance, CBF increased at both levels of PaCO2 by 96 and 69%, respectively. However, VMCA decreased concomitantly. Cerebrovascular CO2 reactivity did not change. CONCLUSIONS: This study demonstrates that during fentanyl/midazolam anaesthesia NTG may cause a major increase in CBF as long as CPP does not decrease considerably. Our results further suggest that NTG causes vasodilation of basal cerebral arteries, inducing a discrepancy between relative changes in CBF and VMCA. Consequently, TCD measurements during infusion of NTG should not be directly compared with preceding measurements of MCA flow velocity.

Blood Pressure↗
PubMed1996

[Comparison of sufentanil-propofol-anesthesia with fentanyl-propofol in major abdominal surgery].

UNLABELLED: Major abdominal surgery often leads to a marked sympathoadrenal stress response with high concentrations of plasma catecholomines, hypertension, and tachycardia. We compared the effects of sufentanil-propofol with fentanyl-propofol anaesthesia in a controlled, randomised, double-blind study of 18 ASA I-II patients aged 23-64 years undergoing major abdominal surgery. Study parameters were haemodynamics (heart rate [HR], arterial [ABP], central venous, and pulmonary arterial pressures, cardiac index [CI]), arterial catecholamine concentrations, and the median frequency of the electroencephalogram (EEG) power spectrum. METHODS: After premedication with flunitrazepam 1-2 mg, promethazine 25-50 mg, and piritramide 7.5-15 mg, a five-lead electrocardiograph and a Lifescan brain activity monitor were attached and indwelling cannulae were inserted into the radial artery and two forearm veins. A thermodilution catheter was placed in the pulmonary artery via the right internal jugular vein. Anaesthesia was induced with either fentanyl 7 micrograms/kg followed by 5 micrograms/kg.h or sufentanil 1 microgram/kg followed by 0.7 microgram/kg.h up to the end of surgery. Additional boli of the opioids were given according to set criteria, resulting in an average consumption of 9.03 micrograms/kg.h fentanyl or 1.22 micrograms/kg.h sufentanil. Propofol 2 mg/kg was given followed by 6 micrograms/kg.h up to the end of surgery. Relaxation was obtained with pancuronium 0.025-0.05 mg/kg before and after induction, after tracheal intubation, before and after skin incision, after opening of the peritoneum, and at the end of surgery. RESULTS: No significant differences were observed between the two groups with regard to the study parameters. The duration of surgery and blood loss were similar in both groups, as were patient characteristics. After induction 2 patients in each group developed thoracic rigidity, which was reversible after muscle relaxation. HR, ABP, and CI decreased significantly before skin incision; after surgical stimulation the baseline values were again reached. but not exceeded. No patient developed tachycardia (> 100/min) or hypertension (> 15% higher than baseline pressure) for longer than 10 min during the study period until the end of surgery. The plasma concentrations of epinephrine and norepinephrine decreased significantly during anaesthesia, and under maximum surgical stimulation did not increase higher than the physiological baseline concentrations. The EEG median frequencies decreased after induction, and during the entire anaesthetic period the main activity was in the delta and theta frequency bands. CONCLUSIONS: With both regimens, the sympathoadrenal stress response to major abdominal surgery was nearly completely suppressed, resulting in stable haemodynamics during the operations. Sufentanil and fentanyl were equally well suited as analgesic components of total i.v. anaesthesia with propofol.

Abdomen↗
PubMed1995

[Is cerebral venous oxygen saturation an indicator of cerebral circulation?].

The arteriovenous oxygen content difference (avDO2) of the brain is dependent on O2 consumption (CM-RO2) and cerebral blood flow (CBF). With unchanging arterial O2 content, avDO2 is inversely related to cerebral venous O2 saturation (SO2). Measurement of SO2 in the jugular bulb not only provides information about the O2 balance of the brain, but may give an important estimation of CBF if a clinically useful correlation is proven. The aim of the present study was to verify this aspect. METHODS. Sixty-two male patients undergoing coronary revascularisation were investigated. The study was approved by the local Ethical Committee and each patient gave written informed consent on the preoperative day. At four points during the perioperative course arterial and cerebral venous SO2 and CBF were measured. Cerebral venous blood was sampled from a catheter in the superior bulb of the right internal jugular vein. CBF was measured using the argon wash-in technique. All sampled data were pooled and evaluated. RESULTS. As expected from theory, cerebral venous SO2 and avDO2 showed a close linear relationship (r = -0.892). However, only a weak hyperbolic relationship was found between cerebral venous SO2 and CBF. In addition, no direct correlation between CMRO2 and SO2 in the jugular bulb could be demonstrated. CONCLUSIONS. In this clinical study, a close relationship between cerebral venous SO2 and CBF was not found. This was primarily due to the high variability of cerebral O2 uptake. Changes in cerebral venous SO2 may therefore not be used as an estimate of perioperative changes in CBF.

Cerebrovascular Circulation↗
PubMed1995

[Hemodynamic effects of new phosphodiesterase inhibitors in patients with coronary heart disease. A comparison between enoximone and R80122].

At present, phosphodiesterase III inhibitors are commonly used for the treatment of low cardiac output states. Despite their positive inotropic and lusitropic effects, these drugs are still under discussion because of certain adverse effects like thrombopaenia, elevation of transaminases, abdominal disregulation, and excessive peripheral vasodilatation. As a consequence, more cardioselective phosphodiesterase inhibitors were developed with the aim of reducing these adverse effects. One of them, enoximone (Marion Merrell Dow, Fig. 1), an imidazole derivative, has nearly no influence on platelets and abdominal organ function. In addition, in many studies vasodilatation was found to be absent. Recently a new substance, R80122 (Janssen, Belgium, Fig. 1), was developed. First experimental studies showed high cardioselectivity of this substance. The aim of this study was to compare the haemodynamic effects of enoximone and R80122 in patients with ischaemic heart disease. METHODS. This study was thoroughly discussed and approved by the local Ethics Committee; all patients gave written informed consent. Twenty male patients (Table 1) with normal left ventricular function who were about to undergo elective coronary artery bypass surgery were randomly allocated to receive a bolus of either 1.0 mg/kg enoximone or 0.3 mg/kg R80122 after induction of anaesthesia. Premedication consisted of 2 mg flunitrazepam orally the evening before and in the morning 1 h before operation. Anaesthesia was induced with 0.007 mg/kg fentanyl, 0.2 mg/kg etomidate, and 0.1 mg/kg pancuronium bromide and maintained by a continuous infusion of 0.02 mg/min fentanyl and 0.3 mg/min midazolam. After induction of anaesthesia haemodynamic measurements were performed and blood gas samples were taken preoperatively under steady-state conditions before and 5, 30, and 60 min after drug administration. RESULTS. The results of both groups are shown in Table 2 as mean values with standard deviations. Individual changes of cardiac index (CI), mean arterial pressure (MAP), and systemic vascular resistance (SVR) are depicted in Fig. 2. Peak percentage changes of the haemodynamic parameters are shown in Fig. 3. Both substances improved cardiac function; 5 min after drug administration CI increased by 31% and 26%, respectively. This was accompanied by increases in stroke volume (13% and 14%, respectively) and heart rate (15% and 10%, respectively). At the same time, there were declines in SVR (38% and 36%, respectively) and MAP (19% and 21%, respectively). Although mean values of pulmonary arterial and wedge pressure decreased after drug administration, these changes were inconsistent and not of clinical relevance. There were no statistically significant differences between the haemodynamic effects of both substances at any time in this study. CONCLUSIONS. Both enoximone and R80122 showed the expected inotropic effects. Nevertheless, both substances have a distinct vasodilative effect, which leads to a decline in MAP. R80122 does not have higher cardioselectivity than enoximone.

Adult↗