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U Braun

Publications and source records attributed to U Braun.

At least 199 records · Page 11Linked to original sources
PubMed1995

Ultrasonographic examination of the small intestine of cows with ileus of the duodenum, jejunum or ileum.

The small intestine of 35 heifers and cows with an ileus of the duodenum, jejunum or ileum was examined ultrasonographically. After a clinical examination, the animals were examined from the right flank and thorax with a 3.5 MHz linear transducer, and the findings were verified by a right flank laparotomy or post mortem. Dilated loops of small intestine with a diameter of more than 3.5 cm were visible in at least one location in all the animals; they were seen predominantly in cross-section or longitudinally. The number of loops of dilated intestine visible from the flank or intercostal spaces was markedly influenced by the site of the ileus. In animals with an ileus of the duodenum, only one intestinal loop was usually visible from the flank or from the 12th, 11th or 10th intercostal spaces. In contrast, more than five dilated loops of intestine were usually visible in animals with an ileus of the jejunum or ileum. The largest diameter of intestine measured from the 12th intercostal space was between 6.5 and 9.9 cm in animals with an ileus of the duodenum, between 3.5 and 9.8 cm in animals with an ileus of the jejunum, and between 4.4 and 5.5 cm in animals with an ileus of the ileum. In the majority of the cows, the contents of the intestines were predominantly echogenic, but in the others they were anechoic. The cause of the ileus could be identified by ultrasonography in only a few cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Ultrasonographic examination of the small intestine of cows.

The small intestine of 50 cows was examined ultrasonographically with a 3.5 MHz linear transducer. The cows were examined on the right side, from the tuber coxae to the eighth intercostal space and from the transverse processes of the vertebrae to the linea alba. The appearance of loops of small intestine and their contents and motility were assessed. In the majority of cases, the intestine contained feed and the contents appeared hyperechoic, but in some cows, the intestinal lumen contained mucus or fluid which was hypoechoic. The cranial part of the duodenum could be viewed longitudinally and in cross-section: its largest diameter varied from 1.1 to 5.4 cm and it could be identified with certainty only medial to the gall bladder, which served as an acoustic window. The descending part of the duodenum was adjacent to the abdominal wall and was enveloped in the hyperechoic greater omentum, differentiating it from the jejunum and ileum. The largest diameter of the descending part of the duodenum varied from 0.9 to 3.7 cm. The ascending duodenum could not be identified because of its anatomical position. Loops of jejunum and ileum were usually viewed in cross-section and sometimes longitudinally; in contrast with the duodenum, they were constantly moving. The average diameter of the jejunum and ileum varied from 2.2 to 4.5 cm.

Animals↗
PubMed1995

Double-blind comparison of the acute effects of two relevant doses of oral nicorandil on central hemodynamics, left ventricular function, and myocardial contractility.

Nicorandil is a nicotinamide derivative with potent vasodilator properties. Oral and sublingual administration of this compound in patients with coronary artery disease resulted in a predominant reduction of afterload and a small decrease in left ventricular preload. The effects of nicorandil in different doses on contractile left ventricular (LV) function, however, are not well defined. The aim of the present study was to assess the effects of nicorandil on hemodynamics, left ventricular volume and function, as well as the LV contractility index dP/dt measured by Millar-tip manometers. A total of 16 patients with coronary artery disease were included in this study. After diagnostic coronary angiography and ventriculography, the patients randomly received either 10 or 20 mg of oral nicorandil. The hemodynamic parameters, cardiac output, and LV end-diastolic and systolic pressures were determined after 15, 30, and 60 minutes, and a second angiogram was performed 60 minutes after administration. The predominant effect was a decrease in the mean aortic pressure with a concomitant decrease in the peripheral arterial resistance. Clinically relevant changes in aortic pressure, systemic vascular resistance, and rate-pressure product, however, were documented only after oral administration of 20 mg nicorandil, as opposed to minimal changes in the 10 mg group. LV volume and cardiac output were not changed significantly. LV contractility remained unchanged during the observation period. The hemodynamic profile of this compound is dose-dependent afterload reduction without a change in contractility. Because there was no concomitant increase in heart rate, calculated oxygen consumption was reduced, especially in the higher dose group.

Adult↗
PubMed1995

Oxygen cost of breathing for assisted spontaneous breathing modes: investigation into three states of pulmonary function.

OBJECTIVE: We investigated the effects of continuous positive airway pressure (CPAP) and pressure support ventilation (PSV) on the oxygen cost of breathing (VO2resp) for different states of pulmonary function. Additionally VO2resp was measured during spontaneous breathing. DESIGN: This was done in a controlled and prospective study. Ventilatory modes were applied randomly. SETTING: Measurements were performed in a quiet room on volunteers (VOL) and inpatients treated for chronic obstructive pulmonary disease (COPD). Post-operative patients after aortocoronary bypass surgery (ACB) were studied on the cardio-thoracic intensive care unit just before and after extubation. PATIENTS: Healthy volunteers (n = 14), postoperative patients after aorto-coronary bypass surgery (n = 15) and patients with COPD (n = 9, xFEV1 47.7%) were the objects of study. INTERVENTIONS: Demand flow CPAP (5 mbar) and PSV (7 mbar, PEEP 5 mbar), using the Hamilton Veolar ventilator, were investigated in comparison to spontaneous breathing. MEASUREMENTS AND RESULTS: VO2 was measured by a Datex Deltatrac metabolic monitor. VO2resp was calculated by subtraction of total oxygen uptake (VO2tot) in controlled mode ventilation (CMV) from that in the respective spontaneous breathing mode. For VOL and COPD patients who were not intubated, a CPAP facemask connected to a short 7.5 mm tube was used as connection to the ventilator. Breathing spontaneously under a canopy system VOL showed a VO2resp of 4.5 +/- 4.0% compared to 9.2 +/- 3.5% for ACB and 15.4 +/- 7.7% for COPD. CPAP changed the VO2resp to 7.8 +/- 3.9%, 12.0 +/- 4.0% and 9.1 +/- 3.6% respectively. PSV reduced the VO2resp to 7.9 +/- 3.8% in ACB and 7.7 +/- 5.5% in COPD. CONCLUSIONS: This investigation confirms findings that postoperative patients have a mild increase in VO2resp. COPD exhibit the highest increase in VO2resp. Tracheal tubes, masks and CPAP on a demand flow apparatus increases VO2resp in volunteers and postoperative patients after cardiac surgery. The same amount of CPAP in contrary reduces VO2resp in patients with COPD. Pressure support ventilation can offset the additional VO2resp induced by CPAP but at the same level does not further reduce VO2resp in COPD patients.

Adult↗
PubMed1995

[The effect of propofol on vomiting after strabismus surgery in children].

Strabismus surgery in children is associated with a high incidence of postoperative nausea and vomiting (PONV). METHODS. Ninety ASA class I and II children aged 6 to 16 years and scheduled for strabismus surgery were randomly assigned to one of the following groups: Group 1 (n=30):thiopentone 4-6 mg/kg i.v., halothane 0.8-1.5%, N2O--O2 2:1, no opioids, droperidol 75 micrograms/kg i.v.; Group 2 (n=30):propofol 2-3 mg/kg i.v., propofol 6-9 mg/kg.h, alfentanil 30 micrgrams/kg.h, N2O-O2 2:1, no antiemetics; Group 3 (n=30):similar to group 2, but ventilation with air and O2 2:1. All patients were mechanically ventilated during anaesthesia and gastric contents were aspirated. Recovery scores were calculated for 2 h, emetic scores for 24 h postoperatively.

Adolescent↗
PubMed1995

[Implantation of a phrenic stimulator in central respiratory paralysis].

Neoplastic or traumatic lesions of the brain stem or the upper spinal cord frequently cause respiratory insufficiency necessitating permanent mechanical ventilation. If the integrity of the diaphragm and its nerves is not affected, adequate ventilation can be achieved by electric stimulation of the phrenic nerves. Diaphragm pacing systems mean the patients can be independent of ventilator treatment. This is a psychological advantage for the patient, giving him or her the option of living in less specialized medical care units and perhaps even at home. CASE REPORT. We report the case of a 47-year-old man with a brain stem tumour, which was resected in large pieces. During the postoperative period an increasingly severe respiratory insufficiency developed, which finally made continuous mechanical ventilation necessary. After the viability of the phrenic nerves and contractility of the diaphragm had been shown by direct stimulation of the nerves to be still intact, it was decided that a diaphragm pacer system should be implanted. A "Diaphragm Pacer System S232 G" (Avery Laboratories, Glen Cove, N.Y., USA: external transmitter, antenna, implanted electrode and receiver) was implanted. Using a supraclavicular approach, phrenic nerve electrodes were placed around each nerve and connected with subcutaneous implants of radio signal receivers. Six days after implantation phrenic nerves were stimulated for a first short period. External antenna loops were taped to the skin over the implanted receiver sites (Fig. 3). The impulses produced by the transmitter were delivered via these antenna loops and led to contraction of the diaphragm, providing almost normal respiration. The duration of stimulation was increased stepwise from 1 h a day to full-time stimulation. Three weeks after implantation of the diaphragm pacer system the patient could be totally weaned from mechanical ventilation. After a further 2 weeks it was possible to discharge him from the intensive care unit, and he was then transferred to a rehabilitation centre.

Brain Neoplasms↗
PubMed1995

Hemodynamics and oxygen metabolism in the pig during long-term hypothermia: comparison of 2 pH strategies.

The aim of this study was to investigate the influence of acid-base management (pH stat or alpha stat) on hemodynamics and oxygen metabolism during long-term hypothermia in the pig. Seventeen female pigs were anesthetized, slowly cooled to 28 degrees C with cooling mats and kept at this temperature for 36 h. Thereafter, slow rewarming was performed with inhalation of a 40 degrees C warm air/oxygen mixture and insulation. Eight of the 17 pigs were ventilated according to the pH stat strategy and 9 according to the alpha stat strategy. Both groups were compared 4 times each for hemodynamics and metabolism during cooling, hypothermia and rewarming. The 2 strategies showed no significant difference in cardiac output, heart rate or mean arterial pressure. The only difference in hemodynamics was observed in mean pulmonary artery pressure and pulmonary artery resistance during hypothermia, showing higher values in pH stat animals. As for oxygen metabolism, oxygen consumption during hypothermia was significantly higher in alpha stat animals. Long-term hypothermia with spontaneous circulation revealed significant differences in oxygen metabolism and pulmonary artery pressure as well as resistance between alpha and pH stat acid-base management. These differences may be of importance when using moderate hypothermia in a clinical or experimental setting.

Acid-Base Equilibrium↗
PubMed1995

Long-term efficacy of d/l sotalol in patients with sustained ventricular tachycardia refractory to class I antiarrhythmic drugs.

The efficacy of d/l sotalol was investigated in 50 patients (43 men, seven women; 33 with coronary artery disease, 15 with dilated cardiomyopathy; ejection fraction 33 +/- 10%) with inducible sustained ventricular tachycardia. Before d/l sotalol a mean of 2 +/- 1 (1 to 4) class I antiarrhythmic drugs were ineffective. In 24 patients (48%) oral d/l sotalol (320 +/- 47 mg.day-1) prevented induction of the ventricular tachycardia; in 23 patients the ventricular tachycardia remained inducible (d/l sotalol 326 +/- 50 mg.day-1). The electrophysiological effects of d/l sotalol did not differ between patients in whom d/l sotalol prevented induction of ventricular tachycardia and those in whom the ventricular tachycardia remained inducible. In two patients, torsade des pointes developed after oral application of d/l sotalol; one patient suffered from severe hypotension even with 80 mg of sotalol per day. During long-term follow-up (27 +/- 12 months) 5/24 patients (21%) had a non-fatal recurrence of ventricular tachycardia (1 week to 21 months), one patient died suddenly and another from progressive heart failure. In patients in whom the ventricular tachycardia could be induced despite oral application of d/l sotalol, control of the ventricular tachyarrhythmia was attempted by the use of sotalol in combination with mexiletine (n = 2), amiodarone (n = 9), catheter ablation (n = 2), antitachycardia surgery (n = 1) or the implantation of an automatic cardioverter defibrillator (n = 12). Recurrence of ventricular tachycardia was observed in four patients without an implanted cardioverter defibrillator. Seven out of 12 patients with an implanted cardioverter defibrillator received appropriate shocks or successful antitachycardia pacing. Although no patient died suddenly, overall mortality was 17% in this group. It is concluded that d/l sotalol is highly effective in the suppression of sustained monomorphic ventricular tachycardia inducible by programmed electrical stimulation. However during a mean follow-up of 27 +/- 12 months a recurrence of ventricular tachycardia was seen in 21% of patients, and one patient died suddenly.

Administration, Oral↗
PubMed1995

Suppurative pleuropneumonia and a pulmonary abscess in a ram: ultrasonographic and radiographic findings.

This report describes a two-year-old White Alpine ram with suppurative pleuropneumonia and a lung abscess. Prior to admission, the ram had been unsuccessfully treated with antibiotics and levamisole. Clinical examination revealed that the general behaviour and condition of the ram were severely disturbed. The rectal temperature and respiratory rate were increased. Auscultation of the lungs revealed increased vesicular sounds. Based on clinical findings, a tentative diagnosis of bronchopneumonia was made. To confirm the diagnosis, blood was taken for serological testing for Maedi-Visna, and endoscopic examination of the respiratory tract and ultrasonographic and radiographic examination of the thorax were performed. Cytologic and bacteriologic examination of tracheal secretions revealed large numbers of neutrophils and Actinomyces pyogenes organisms. A pocket of gas, surrounded by a capsule of soft tissue density, overlying the base of the heart, and a horizontal fluid line were observed on radiographs. Ultrasonographic examination revealed an effusion between the pleura and the lung on the left side of the thorax; an encapsulated abscess was seen on the right side of the thorax. Centesis and aspiration of this accumulation of fluid yielded foul-smelling pus. Post mortem examination confirmed the clinical, radiographic and ultrasonographic findings. The ram had severe chronic suppurative pleuropneumonia with abscess formation between the pleura and lung on the right side.

Actinomyces↗
PubMed1995

Diagnosis of liver flukes in cows--a comparison of the findings in the liver, in the feces, and in the bile.

Percutaneous ultrasound-guided cholecystocentesis and aspiration of bile were attempted in 176 cows. These same procedures were performed in another 100 cows immediately after slaughter. The bile samples were examined microscopically for large and small liver fluke eggs. In addition, a fecal sample from each cow was examined for liver fluke eggs. The findings of both groups were summarized, and the results of the fecal and bile sample examinations were compared. In all cows the liver was examined for flukes, and the results were used as a reference. Of 41 cows in which adult flukes were found in the liver, 28 had F. hepatica eggs in fecal samples and 40 had F. hepatica eggs in bile samples. Of 204 cows in which no adult flukes were found in the liver, 23 had F. hepatica eggs in fecal samples and 27 had F. hepatica eggs in bile samples. The sensitivity of the determination of F. hepatica eggs in fecal and bile samples was 68 and 98%, respectively. The negative predictive values for fecal and bile examination were 93 and 99%, respectively. Of 49 cows in which adult flukes were observed in the liver, 13 had D. dendriticum eggs in fecal samples and 44 had D. dendriticum eggs in bile samples. Of 176 cows in which no adult flukes were found in the liver, 19 had D. dendriticum eggs in fecal samples and 49 had D. dendriticum eggs in bile samples. The sensitivity of the determination of D. dendriticum eggs in fecal and bile samples was 27 and 90%, respectively. The negative predictive values for fecal and bile examination were 81 and 96%, respectively. The results of this study indicate that the examination of bile is clearly a more reliable method of diagnosing liver fluke infections than microscopic examination of feces.

Animals↗
PubMed1995

Echocardiographic diagnosis of a cardiac fibrosarcoma in the right atrium of a sheep.

This is a case report of a six-year-old female White Alpine sheep with a cardiac fibrosarcoma in the right atrium. Clinically, the sheep had right-sided cardiac insufficiency with tachycardia, engorgement of the jugular veins, brisket edema, and ascites. Chronic congestion of the liver resulted in increased hepatic enzyme activity. Based on clinical findings, a tentative diagnosis of endocarditis or pericarditis was made. Radiography of the thorax revealed hydrothorax. An echogenic mass was observed in the right atrium via echocardiography; it was interpreted as a tumor or thrombus. Ultrasonography of the abdomen revealed severe ascites and chronic congestion of the liver attributable to right-sided cardiac insufficiency. The clinical and sonographic findings were verified at post mortem. The mass in the right atrium was a pedunculated fibrosarcoma.

Animals↗
PubMed1995

[Ultrasonographic findings of perivascular jugular vein diseases in cattle].

Ultrasonographic examinations were used to characterise and describe perivascular changes of the jugular vein like abscess, hematoma and periphlebitis. Well circumscribed masses with irregular, multiple, hypoechogenic areas, corresponding to fluids and necrotic tissues, suggested an abscess. A fresh hematoma, adjacent to the wall of the vein was shown as a clearly delineated structure with a hyperechogenic content. Cases with periphlebitis were characterised by a diffuse anechoic accumulation of fluids infiltrating the perivascular tissue. The diagnoses were proven by needle aspiration biopsy using ultrasound control.

Abscess↗
PubMed1995

[Analgesia and sedation in patients with head-brain trauma].

The goal of therapy in patients with severe head injury is to avoid secondary brain damage. Analgesia and sedation are an essential part of the therapy, and several drugs are in current use. However, few controlled clinical trials have been performed so far, and none of these drugs has proved to be superior. Although in the past the therapy has been focused on controlling elevated intracranial pressure (ICP), many authors emphasize the role of cerebral ischaemia in the prognosis of patients. Therefore, cerebral perfusion pressure (CPP) i.e. the difference between ICP and mean arterial pressure (CPP = MAP-ICP), seems to be more important than ICP alone. Analgesics and sedatives reduce the cerebral metabolic rate (CMR), and the consequent decrease in cerebral oxygen uptake might prevent ischaemic damage in regions with low perfusion. Moreover, a decrease in CMR is often associated with a decrease of cerebral blood flow (CBF) in regions with normal perfusion and, as a result, ICP is also reduced. Basically, the cerebral effects (on ICP, CMR, and CBF) and the haemodynamic effects with respect to maintenance of a sufficient CPP are most important in the selection of drugs for analgosedation. In addition, the effects on general intensive care management must be considered (pulmonary function, immunreactivity bowel motility). The purpose of this paper is to describe drugs commonly used for analgosedation in severe head injury. Barbiturates bring about the most pronounced decrease of CMR and ICP. In the past these drugs were used routinely in high doses ("barbiturate coma"). However, no improvement in outcome was demonstrable, and vitally dangerous side effects, such as infection, pulmonary dysfunction, arterial hypotension, and renal failure often occurred. High-dose barbiturate therapy is therefore only indicated in exceptional cases, such as refractory increase in ICP with preserved CO2 response of cerebral vessels. The effect is dependent on CMR at the start of this therapy. Benzodiazepines are frequently used in patients with head injury. They cause only a moderate decrease of CMR and ICP. In general, side effects are negligible. However, a possible decrease of MAP by reduced central sympathetic drive has to be taken into account. Opioids are also frequently used in patients with head trauma. The observed cerebral effects are inconsistent. Some authors have described increases in ICP, CBF, and CMR, but in most studies no influence on these values, or a decrease, has been observed. In any case, cautious titration of these drugs and cerebral monitoring are therefore desirable. As with benzodiazepines, a decrease in MAP due to central effects is possible. In addition, opioids inhibit bowel motility. Ketamine is generally used because of its favourable circulatory effects, bronchodilatation and absence of inhibition of bowel motility. In patients with increased ICP, however, it is often considered contraindicated, since it can be associated with cerebral vasodilation and ICP increase. Other studies did not confirm an increase of ICP when controlled ventilation and additional sedation were applied. More recent studies have demonstrated the role of neuroexcitatory NMDA-receptors in ischaemic and traumatic brain damage. Since ketamine exerts an antagonistic effect on N-methyl-D-aspartate receptors (NMDA) and studies in animals have demonstrated a protective effect of ketamine against ischaemic and traumatic brain damage, controlled clinical studies in patients with head injury are desirable. Propofol results in a profound decrease of CMR and a significant decrease of ICP, but often also in haemodynamic depression. Few results obtained during long-term administration are available, but it seems to be beneficial. More clinical studies are warranted. Gamma-hydroxybutyrate (GHB) is a physiological substance, which has only sporadically been investigated for sedation in patients with head trauma. The few available studies show beneficial res

Analgesics↗
PubMed1994

Comparison of ultrasonographic and radiographic findings in cows with traumatic reticuloperitonitis.

The radiographic and ultrasonographic findings in 26 cows with traumatic reticuloperitonitis were compared. The cows were divided into three groups based on the radiographic findings; the first group consisted of 12 cows in which the principal radiographic finding was a foreign body penetrating the reticulum; the second group contained four cows in which the principal radiographic finding was gas shadows or a gas-fluid interface, the third group consisted of 10 cows that had no reliable radiographic evidence of traumatic reticuloperitonitis, such as an abnormal contour, position or shape of the reticulum. In no case could the foreign bodies be visualised by ultrasonography. In all the cows except one with radiographic evidence of abnormal gas inclusions and gas-fluid interfaces, ultrasonography revealed echogenic, partitioned and capsulated structures with central hypoechogenic cavities. In addition, in some of the cows with no radiographic evidence of the condition, severe changes indicative of inflammatory processes were visible by ultrasonography.

Animals↗
PubMed1994

A new paediatric metabolic monitor.

OBJECTIVE: A paediatric option for the measurement of VO2 and VCO2 (20 to 150 ml/min) has recently been introduced for the adult Deltatrac metabolic monitor (Datex Instrumentarium, Finland) to use in ventilated and spontaneously breathing children. This paper describes a laboratory validation of the paediatric option for ventilated children with regard to the influence of respiratory variables. DESIGN: Respiratory variables were varied within the following ranges: FIO2 0.21-0.8, FIO2-FEO2 (DFO2) 0.01-0.05, FECO2 0.01-0.05, VE 300-6000 ml/min, VT 8-300 ml, RR 10-50/min, P(aw) 10-60 mbar, relative humidity 10% and 60%, and resulted in 107 test situations. SETTING: Gas exchange was simulated by injection of nitrogen and CO2 at a RQ close to 1. PATIENTS OR PARTICIPANTS: Different situations of paediatric patients ventilated in controlled mode were simulated on a gas injection model. INTERVENTIONS: Respiratory and metabolic variables were varied independently to result in a range of 8 to 210 ml/min of VO2 and VCO2. MEASUREMENTS AND RESULTS: Reference measurements were carried out by mass spectrometry and wet gas spirometry. The mean VCO2 difference for all tests ranging from 20 ml/min to 210 ml/min was -2.4% (2SD = +/- 12%). The respective VO2 difference was -3.2% (2SD = +/- 23%). Measurement agreement for VO2 in neonatal respirator treatment (20-50 ml/min) compared to older children (50-210 ml/min) showed a mean difference of -3.9% (2SD = +/- 26%) versus -2.8% (2SD = +/- 20%). The respective differences for VCO2 were -7.1% (2SD = +/- 7%) versus +0.4% (2SD = +/- 10%). The mean difference for VO2 as well as VCO2 indicated a high systematic agreement of both methods. The variability (+/- 2SD) in VCO2 measurement is acceptable for all applications. The overall variability in VO2 measurement (2SD = +/- 23%) can be reduced by exclusion of all tests with a FECO2 and DFO2 below 0.03. This results in a mean difference of -3.2% (2SD = +/- 13.7%). CONCLUSION: Within this limitation the paediatric measurement option seems to introduce a valuable method for clinical application in paediatric intensive care medicine.

Calibration↗
PubMed1994

[The laryngeal mask as an instrument].

The laryngeal mask (LM) was developed by A. Brain to overcome the disadvantages of the face mask (impractical) and the tracheal tube (invasive). Today this new instrument is applied on a broad scale in Great Britain and with growing interest in continental Europe. The laryngeal mask comes in five sizes to fit five different age groups. The blindly applied technique of positioning the LM can be easily learned. Spontaneous or artificial ventilation is possible if the LM is in the correct position. Mechanical ventilation may lead to the insufflation of air into the stomach. Therefore, ventilatory peak pressure should not exceed 20-25 cm H2O and ventilation must be closely monitored. The risk of aspiration can be avoided by the proper selection of patients. The LM may be used with different anaesthetic techniques; muscle relaxant drugs are not mandatory. The authors have applied this mask more than 300 times, and this new instrument obviously has potential for different clinical indications. The LM may be applied for short surgical interventions in all age groups except premature infants. Complications such as regurgitation, aspiration and laryngospasm can be avoided by the awareness of the anaesthetist and by an adjusted deep plane of anaesthesia. Apart from anaesthesia, the LM can be used for bronchoscopy in children, for difficult intubations and as a preliminary airway in cases of resuscitation. Two studies performed in Great Britain have evaluated the LM for resuscitation. The investigations should be confirmed in German-speaking countries.

Humans↗
PubMed1994

[Postoperative warming therapy in the recovery room. A comparison of radiative and convective warmers].

Hypothermia (Tcore < 36 degrees C) can be observed in 60%-80% of all admissions to the post-anaesthetic recovery unit. Effective warming devices may accelerate rewarming, improve patient comfort, and suppress shivering thermogenesis. This study was designed to compare the efficiency of warming devices in extubated postoperative patients and their effect on postoperative oxygen uptake (VO2). METHODS. Thirty-five ASA I and II patients after laparoscopic hernioplastic repair with core temperatures < 36 degrees C were randomly assigned to either postoperative nursing under a radiant heater (group R, n = 11, Aragona Thermal Ceilings CTC X, Aragona Medical AB, Täby, Sweden), a forced air system (group L, n = 12, Bair Hugger, Augustine Medical Inc., Eden Prairie, Minnesota, USA), or a normal cotton hospital blanket (group K, n = 12). Anaesthesia was conducted totally intravenously with propofol, alfentanil, and vecuronium. Mean body temperature and total body heat were calculated from urinary bladder temperature and four subcutaneous temperature measurements. The rate of thermogenesis was calculated from continuous measurement of VO2 (Datex Deltatrac Metabolic Monitor, Datex Instrumentarium Corp., Helsinki, Finland). Heat balance was derived from the increase in total body heat minus body heat production. Heart rate and noninvasive blood pressure were measured by the Cardiocap (Datex Instrumentarium Corp., Helsinki, Finland). All data were transferred to an IBM-compatible computer at 60-s intervals. Measurements were stopped when core temperature reached 37 degrees C. The rate of change was calculated for each variable for the period 15 min after the beginning of rewarming to attainment of 37 degrees C. Data are presented as median, minima, and maxima (min<==>max); the Mann-Whitney U test was used to test for significance of group differences. RESULTS. All groups were comparable for body weight, height, age, and amount of postoperative infusions. Temperatures at admission were 35.2 (33.4<==>35.9), 34.7 (34.3<==>35.8), and 35.4 (34.3<==>35.9) degrees C for groups R, B, and K, respectively. No significant differences in the rate of central rewarming could be found for these groups with 0.81 (0.41<==>1.32), 0.76 (0.40<==>1.07), and 0.70 (0.37<==>1.13) degrees C/h (Fig. 1). The mean VO2 of 3.41 (3.07<==>3.73), 3.55 (2.78<==>4.06), and 3.79 (2.51<==>7.00) ml/kg/min also did not differ significantly (Fig. 3). Significant differences between groups R and B [4.39 (3.74<==>6.19) and 4.30 (3.46<==>6.67) ml/kg/min] and K [5.92 (3.79<==>10.64) ml/kg/min] were found for VO2 maxima during the course of investigation (Fig. 4). The heat balance revealed significant differences among treatment and control groups with -88 (-226<==>+30), -41 (-212<==>+12), and -191 (-265<==>-86) kJ/h for groups R, B, and K. We additionally calculated the heat balance as a quotient, which showed 0.70 (0.22<==>1.07), 0.86 (0.44<==>1.04), and 0.49 (0.31<==>0.79) for groups R, B, and K (Fig. 4). The mean rate-pressure product of all groups did not differ significantly during the period of investigation. CONCLUSIONS. Neither external heat supply by radiant heat nor by a forced warm air system significantly reduced rewarming time in extubated, awake patients. As measured by heat balance, both active treatments saved about 20% more body heat production than in the control group. Continuing peripheral vasoconstriction may be the reason for the low efficiency of heat transfer. Thermal treatment did reduce the peak load (max. VO2) on the oxygen transport systems, though shivering was treated by pethidine if it occurred. External rewarming did not reduce the average load (mean VO2). Thus, concerning the goal of accelerating rewarming, it appears more rational to prevent intraoperative heat loss. For a comparison of efficiency of different warming devices, postoperative extubated patients do not appear to be an ideal model for study.

Adult↗