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N Mutz

Publications and source records attributed to N Mutz.

At least 19 recordsLinked to original sources
PubMed1992

Atrial natriuretic factor release during hypovolemia and after volume replacement.

OBJECTIVE: To examine plasma atrial natriuretic factor activity during hypovolemia and after vascular volume replacement. DESIGN: Prospective, descriptive study. SETTINGS: Scene of emergency, Emergency Department, and the ICU of a university hospital. PATIENTS: A total of 47 trauma patients with evidence of hypovolemia were grouped according to their major injury into a thoracic injury group (15 patients; mean Injury Severity Score = 38.5 +/- 3.1 [SEM], Hospital Trauma Index = 14.1 +/- 0.7), an abdominal injury group (14 patients; Injury Severity Score = 36 +/- 3.3, Hospital Trauma Index = 14 +/- 0.9), and a severe head injury group (18 patients; Injury Severity Score = 23 +/- 1.5, Hospital Trauma Index = 10 +/- 0.6). MEASUREMENTS AND MAIN RESULTS: Measurements were taken at the scene of emergency; after volume replacement in the Emergency Department; and after 3, 7, 12, 24, 36 hrs and on day 5 in the ICU. In all groups, the average plasma atrial natriuretic factor levels were increased at the scene of emergency and declined significantly to normal values with volume replacement. In the thoracic injury group, plasma atrial natriuretic factor activity decreased from 253 +/- 73 to 115 +/- 83 pg/mL (p less than .0017); in the abdominal injury group, plasma atrial natriuretic factor activity decreased from 194 +/- 42 to 91 +/- 24 pg/mL (p less than .006); in the severe head injury group, plasma atrial natriuretic factor activity decreased from 167 +/- 28 to 70 +/- 13 pg/mL (p less than .02) with volume replacement. Plasma atrial natriuretic factor levels at the scene of emergency were significantly (252 +/- 73 vs. 167 +/- 28 pg/mL; p less than .05) higher in the thoracic injury group and in the abdominal injury group (194 +/- 42 vs. 167 +/- 28 pg/mL; p less than .05), as compared with the severe head injury group. CONCLUSIONS: In trauma patients, plasma atrial natriuretic factor concentrations were markedly increased in patients with untreated hypovolemia and were decreased to normal values with vascular volume replacement. Thus, atrial natriuretic factor seems to play an important physiologic role during hypovolemia.

Abdominal Injuries↗
PubMed1990

Gamma scintigraphic imaging of lung microvascular permeability in adult respiratory distress syndrome.

The sequence of lung microvascular permeability (LMVP) changes in early direct posttraumatic and late indirect pancreatitis-induced adult respiratory distress syndrome (ARDS) was studied and compared with that of a control group, as well as non-ARDS ICU patients. A computerized large field of view gamma camera was used to measure LMVP simultaneously over both lungs by In 113m-labeled transferrin and Tc 99m-labeled erythrocytes. The LMVP index (LMVPI) (%/h) was used to quantify LMVP in the dynamic scintigraphic measurement. In the control group the LMVPI was 2.6 +/- 2.8%/h for the right and 2.0 +/- 2.8%/h for the left lung. Similar values were found in mechanically ventilated ICU patients without ARDS (group A) on admission (right LMVPI 3.2 +/- 2.6, left LMVPI 2.6 +/- 2.7%/h) and 4 days later (right LMVPI 3.9 +/- 2.6, left LMVPI 2.3 +/- 1.8%/h). Interestingly, the initial evaluation of patients with direct early posttraumatic ARDS (lung contusion) (group B) showed significantly (p less than .01) elevated LMVP for the contused side (LMVPI 10.8 +/- 5.1%/h), but normal values for the nontraumatized lung (LMVPI 3.9 +/- 3.4%/h), whereas 4 days later the LMVP increased significantly (p less than .05) on the primarily healthy side (LMVPI 8.0 +/- 5.0%/h) while remaining elevated for the traumatized lung (LMVPI 10.9 +/- 6.0%/h).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Infusion or repetitive bolus injection? A clinical study of midazolam/fentanyl and diazepam/fentanyl combination anesthesia in neurosurgical operations].

The objectives of this study were to compare two narcotic/benzodiazepine combinations given either as continuous infusion or intermittent bolus injections in neurosurgical patients. 24 patients scheduled for elective craniotomy were investigated. They were assigned randomly to four different groups for treatment. Groups 1 and 2 received a combination of midazolam and fentanyl, groups 3 and 4 a combination of diazepam and fentanyl. Anaesthesia was maintained either by continuous infusion (groups 1 and 3) or intermittent bolus injections (groups 2 and 4). At six key intervals cardiovascular variables were compared. Furthermore, total drug dosage requirements were measured and compared. Except for measurement 3 (skin incision), cardiovascular dynamics were not markedly different between bolus and infusion groups. Haemodynamic response to skin incision was less in both bolus groups. Furthermore, the bolus technique revealed a non-significant reduction in total drug dosage requirements in the bolus groups. Our data indicate that for neurosurgical anaesthesia conventional bolus injection of intravenous anaesthetics is superior to continuous infusion with respect to intraoperative haemodynamics. The typically reduced level of pain with short peaks only, characteristic for neurosurgical operations, is one of the factors contributing to these surprising results. Furthermore, the simple method of infusion chosen influences the results decisively. Certain advantages might be achieved by the use of sophisticated pharmacokinetic infusion models. Total drug dosage requirements were reduced in the bolus groups mainly because of the typical anaesthetic requirements of craniotomy, disposing it for bolus technique.

Adult↗
PubMed1990

[The automated determination of the dibucaine number using the Greiner G450 selective analyzer. A routine parameter of significance?].

UNLABELLED: Patients who are homozygous for an atypical pseudocholinesterase enzyme (PCHE) suffer a prolonged neuromuscular block after succinylcholine application. In order to determine which patients have atypical PCHE preoperatively, an automated method using the Greiner G450 analyzer was developed. PATIENTS AND METHODS: The contribution of blocked and unblocked PCHE by dibucaine hydrochloride (optimal concentration 10(-4) mol/l;) was determined in 113 patients (ASA groups 1-2) and the dibucaine number (DN) was evaluated. RESULTS: According to the DN, the patients were subdivided into three groups: group A (PCHE 5.01 +/- 1.64 kU/l, DN 74.47 +/- 0.87); group B (PCHE 4.28 +/- 3.41 kU/l, DN 64.95 +/- 3.41); group C (PCHE 1.33 +/- 0.54 kU/l, DN 13.08 +/- 2.19;). PCHE and DN of group A corresponded with normal standard values, whereas the patients in groups B and C could be considered to be patients with heterozygous and homozygous atypical PCHE, respectively. CONCLUSIONS: Our data indicate that an automated analysis of blocked and unblocked PCHE with the Greiner G450 can be easily done in a routine laboratory. By interpreting the DN, the possible risks of delayed succinylcholine degradation can probably be prevented.

Butyrylcholinesterase↗
PubMed1990

[The course of extravascular lung water in severely injured patients in intensive care with and without thoracic trauma].

In patients with multiple injuries, the development of permeability edema can be assumed. However, no uniform shape of this fluid accumulation can be found even in the presence of severe injuries. Based on the first clinical observations, our aim was to search for correlations between the development of extravascular lung water (EVLW) and the individual injury pattern in severely traumatized ICU patients. PATIENTS and METHODS. Our investigations were performed in 48 artificially ventilated ICU patients. According to the prevailing injury pattern patients were divided into three groups: group A: 18 patients (mean age: 32 years, mean Injury Severity Score (ISS) = 29) with isolated thoracic trauma; group B: 10 patients (mean age: 27 years, mean ISS = 42) with severe multiple trauma but without any thoracic injury; group C: 20 patients (mean age: 33 years, mean ISS = 43) with severe multiple trauma and concomitant thoracic trauma. In all patients (group A, B, C), EVLW was determined by means of a double indicator method on a daily basis from the patient's admission to the ICU (day of trauma) until day 10. Additionally, the hemodynamic parameters (heart rate, mean arterial pressure, mean pulmonary arterial pressure, pulmonary capillary wedge pressure and cardiac index) were determined at the same time. RESULTS. As shown in Fig 1, EVLW was slightly elevated on day 1. However, on day 2 EVLW decreased within normal values and remained in that range until the end of the observation period. On day 3 a slight and fleeting increase of EVLW, but within normal range, can be seen. In group B (Fig.2), EVLW can be observed within normal range within a period of 4 days. Starting from day 5 until day 7 a marked increase (p greater than 0.01) in EVLW can be seen. From that maximum point EVLW development reverses slightly until day 10--however, without returning to the normal range. In group C, a marked biphasic pattern can be seen due to EVLW maximum values on post-traumatic days 3 and 7. However, in this group the EVLW was in the pathological range during the whole observation period. No statistically significant differences could be seen, when looking at hemodynamic variables. CONCLUSION. Isolated thoracic trauma will not lead to a marked pathological elevation of EVLW within the lungs. Moreover, EVLW decreases rapidly within a short time period. Based on our results, it seems that severe extrathoracic injuries will intensify microvascular injury in the initial period, as shown in our patients in group C. Increase of EVLW at a later time (day 7), as observed in groups B and C, is possibly the expression of a mediator and activator-induced "septiformal" injury of the microvascular endothelium. This may be caused by the underlying massive peripheral soft-tissue trauma. Specific elevations of EVLW subsequent to the individual injury pattern can indicate that that process has begun and is responsible for the origin of the microvascular injuries.

Adolescent↗
PubMed1990

[Determination of hemoglobin concentration using the hemoglobin azide method in traumatic emergencies].

UNLABELLED: The present study examined the clinical practicability of a new hemoglobin measurement device based on a modified azide-methemoglobin reaction (HiN3 method) in trauma patients. The accuracy of the HiN3 method was compared to the internationally well accepted hemiglobincyanide method (HiCN method) in arterial, capillary, and venous blood samples. PATIENTS AND METHODS: 1. Comparison of the methods. In 62 trauma patients, hemoglobin measurements using the HiN3 method were compared to results obtained by the HiCN method. Blood samples were taken simultaneously from the same patient to evaluate each measurement procedure in arterial (group 1), capillary (group 2), and venous blood samples (group 3). 2. Accuracy. To evaluate the accuracy of both methods we compared two venous blood samples taken simultaneously from the same patient. 3. Reproducibility. For measurement of the reproducibility of the HiN3 method, the first two results of each three-time-measurement were compared. Statistical analysis of the results was performed using regression analysis. RESULTS: 1. Comparison of the methods. Comparing the results of hemoglobin measurements resulting from the HiN3 and HiCN methods, a strong correlation was found in arterial (Fig. 2), capillary (Fig. 3), and venous blood (Fig. 4). 2. Accuracy. The HiN3 method had an accuracy of +/- 1.47% and the HiCN method +/- 2.55%. 3. The reproducibility of the HiN3 method was +/- 1.25% (Fig. 5); however, one pair of samples did show a significantly different initial value (Hb 8.4 g/dl in I, but 10.4 g/dl in I and III). DISCUSSION: From our examinations in trauma patients, we can recommend this easy to handle device, particularly for acute diagnostic purposes in emergency patients and for trend evaluations both in the hospital and in the prehospital period for rapid and precise hemoglobin determinations.

Adult↗
PubMed1989

Influence of end-expiratory lung volume on carbon dioxide elimination during high frequency ventilation in dogs.

We have examined the effect of varying end-expiratory lung volume on carbon dioxide elimination in 10 mongrel dogs undergoing conventional mechanical ventilation at 12 b.p.m. and forced diffusion ventilation (FDV) at 6 Hz and 50 Hz and continuous flow. End-expiratory volumes were altered by changing the pressure in a plethysmographic box in which the dogs underwent ventilation. The pressures studied were atmospheric, sub-atmospheric (box pressure -1.0 kPa) and increased atmospheric (box pressure + 0.5 kPa). The results indicated that more carbon dioxide was eliminated at low lung volumes and this was most pronounced with HFV at 50 Hz and continuous flow. It is postulated that changes in airway geometry and different lung volumes may alter the distance between the gas interface in the conductive airways and the respiratory zone and so alter the efficiency of ventilation during FDV.

Anesthesia↗
PubMed1989

Influence of high frequency ventilation at different end-expiratory lung volumes on the development of lung damage during lung lavage in rabbits.

The effects of high frequency ventilation in combination with sustained inflations was studied in the surfactant-deficient lungs of 18 New Zealand White rabbits (weight 1.9-2.1 kg) during anaesthesia with urethane and neuromuscular block with pancuronium. Lung damage was induced by repeated lung lavage. In nine rabbits (group I) baseline ventilator settings were maintained constant throughout the study and airway pressure was readjusted to achieve a constant tidal volume. In the other nine rabbits (group II), ventilation was reinstituted after lung lavage with one period of four sustained inflations followed immediately by high frequency ventilation. In group I there was a significant decrease in gas exchange for oxygen and deterioration in pulmonary mechanics, whereas in group II there was little change in baseline blood-gas values or pulmonary mechanics. These data suggest that, with adequate ventilatory management during the period of lung lavage, the lung damage produced by this manoeuvre may be obviated.

Anesthesia, Intravenous↗
PubMed1989

[The behavior of hGH (human growth hormone) and somatomedin C following anesthesia induction with propofol in comparison with diazepam and thiopental].

It was the aim of present study to examine possible interactions between human growth hormone (hGH) and Somatomedin C (SmC), when inducting anaesthesia with propofol in healthy patients. Moreover these effects of propofol should be compared with that of diazepam and thiopentone. 30 patients scheduled for elective plastic-surgery were divided randomly into 3 groups. Induction of anaesthesia was performed in group 1 with diazepam, in group 2 with thiopentone and in group 3 with propofol. Measurements of hGH, SmC as well as blood glucose were performed at 4 different given times: (1.) preoperatively, (2.) 15 minutes, (3.) 30 minutes, (4.) 60 minutes after inducting anaesthesia. Diazepam and thiopentone lead to increases in hGH secretion already in a very early phase after induction of anesthesia (15 minutes) and remained on elevated level. Concentrations of Somatomedin C, as well as of blood glucose, however, remained unchanged during the whole observation period. In comparison to that findings propofol did not show any influence on hGH and consecutively on Somatomedin C activity at any time. Based on our results we can conclude that propofol should be the induction-agent of choice predominantly when anaesthetizing patients with unknown hormonal state (outpatients scheduled for operation).

Adult↗
PubMed1988

[Response of human growth hormone to anesthesia induction with propofol].

Although there are distinct differences in both pharmacokinetics and chemical structure, propofol has sedative effects similar to those of benzodiazepines. Both diazepam and thiopental, commonly used agents for inducing anaesthesia, show some typical neuroendocrine effects such as liberation of human growth hormone (hGH) in addition to their well-known influences on the cardiovascular system. It was our aim to examine the endocrine response of hGH after induction of anaesthesia with propofol and to compare any possible effects with those of diazepam and thiopental. The study was performed on 30 non-premedicated patients, who underwent plastic-surgery (mean age: x = 35 +/- 8.3 years, mean body weight: x = 68.9 +/- 23.2 kg). No signs of endocrine disturbances were found in the patients prior to the study. Patients were divided in a random fashion into 3 groups of 10 persons each: In group 1 propofol was given in a bolus injection (2 mg/kg) and then by infusion for a period of 10 min (0.2 mg/kg/min). In group 2 diazepam (0.3 mg/kg) and in group 3 thiopental (5 mg/kg) were administered as a bolus to induce anesthesia. All patients were intubated immediately after induction of anesthesia and then relaxed using vecuronium (1 mg/kg). Ventilation was performed mechanically during the entire operative period (N2O/O2 - FiO2:0.33, tidal volume 10 ml/kg, respiratory rate: 14/min). To maintain anesthesia halothane (0.5-1.0 vol.-%) and meperidine (0.75 mg/kg) were added 15 min after induction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[High frequency ventilation with a conventional respiratory following heart surgery interventions].

This study was designed to compare the effects of Continuous Positive-Pressure Ventilation (CPPV) and, by using the same unmodified conventional ventilator, High-Frequency Positive-Pressure Ventilation (HFPPVkonv). First, CPPV and HFPPVkonv were studied in a lung model with both normal (R = 5 mbar/1/second) and elevated (R = 20 mbar/1/second) resistance. Our results indicate that in HFPPVkonv the large compressible volume of the conventional ventilator did not influence lung model ventilation at normal resistance. The adjusted (300 ml) tidal volume (VT) and the measured volume of actual expiration (270 ml) were about the same (Fig. 1). However, with elevated resistance air trapping occurred. The large compressible volume influenced model ventilation during both CPPV and HFPPVkonv (Fig. 2). As a second step we evaluated the effects of HFPPVkonv on gas exchange, airway pressure, and hemodynamics in 12 patients (aged 43-69) postoperatively after elective cardiac surgery. After a period of stabilization at the intensive care unit every patient was first ventilated with CPPV. The ventilator settings were: VT = 10-12 ml/kg, inspiratory: expiratory ratio (I:E) = 1:2, frequency (F) = 12/min, V = 60 1/min, PEEP = 5 cm, FiO2 = 40%. After 20 min of CPPV baseline measurements were made (series I). Then the initial ventilator settings of CPPV were switched to HFPPVkonv, the conventional ventilator remaining unmodified. The settings were changed as follows: I:E = 1:3, F = 60/min, V = 120 1/min, PEEP = 5 cm, FiO2 = 40%. During 60 min of HFPPVkonv variables were measured first after 20 min (series II) and again after another 40 min (series III). Minute volume had to be doubled after changing from CPPV to HPFFVkonv to achieve eucapnia. As a result of the new ventilatory settings, VT and hold showed a significant decrease (P less than 0.01) (Table 2).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

[Treatment of re-expansion edema ('unilateral ARDS") after rapid pneumothorax drainage].

A rare complication after delayed re-expansion of pneumothorax is reported. A polytraumatized patient with stable vital functions was admitted to our ICU immediately after surgery. Later, oxygenation worsened treated by a rise in FiO2. Concomitant tachycardia was thought to be due to increasing body temperature. On day 3 of treatment in the ICU further deterioration in gas exchange (and in hemodynamics, with complete collapse of the left lung) was diagnosed on X-ray examination. Retrospectively, the development of this condition could be traced on the X-ray films taken during the previous 3 days. Thoracic drainage and suction resulted in complete re-expansion of the lung. After re-expansion worsening of gas exchange and unilateral ARDS-like configurations were observed on chest X-ray. Reversal of the I:E ration and a rise in PEEP improved gas exchange and the X-ray appearance immediately. In the next few days the intensity of the respiratory treatment could be reduced, and after a short period of CPAP the patient was discharged from the ICU. Three mechanisms for development of this "unilateral ARDS" are discussed: loss and suppressed regeneration of surfactant in prolonged atelectic alveolar compartments; increased capillary fluid escape due to suction; and increased complement activation and reduced degradation of edematogenic bradykinin in hypoxic alveolar compartments. Possible clinical implications for the treatment of longer duration pneumothorax are: fractionated drainage and respirator settings, reopening collapsed alveoli in an inhomogeneously diseased lung such as IRV.

Adult↗