[Palliative care oriented therapy for all patients : recommendations of an expert circle]

BACKGROUND

Since 2011 palliative care has been a compulsory part of the German medical study course (so-called Q13 palliative and pain medicine). Palliative care content does not, however, as often taught, have to focus only on patients in the so-called palliative stages of disease. The aim of this investigation was to encourage a discussion concerning the integration of palliative care aspects into general medical treatment.

METHODS

For data collection an open discussion of the main topics by experts in palliative medical care was used. The main outcome measures and recommendations included responses regarding current practices related to expert opinions, national and international literature and one case report. The literature search was performed using the databases "PubMed", "Medline" and "Google" (1990-2011).

RESULTS

As an important consensus, the following recommendations for optimization of inpatient and outpatient care were: (1) integration of aspects of palliative care into medical curricula of all disciplines, (2) palliative care content should be extended to the general optimization of therapy for all patients, (3) palliative medicine should be part of the everyday medical practice in all disciplines and (4) palliative medicine should not be isolated as "death medicine" or medicine of the dying patient.

CONCLUSIONS

Palliative care treatment is increasingly becoming integrated into medical education and into medical curricula of all disciplines. Palliative ideas and goals are focussed on patients in the so-called palliative stages of disease. Furthermore, palliative medicine is often described as the medicine of dying patients. As a result of this study it seems to make sense to extend palliative care aspects to all patients and to all patient care. The extent to which such opportunities exist and such health care is economically feasible remains to be the subject of further clinical studies.

[Palliative care and end-of-life patients in emergency situations. Recommendations on optimization of out-patient care]

BACKGROUND

At the end of life acute exacerbations of medical symptoms (e.g. dyspnea) in palliative care patients often result in emergency medical services being alerted. The goals of this study were to discuss cooperation between emergency medical and palliative care structures to optimize the quality of care in emergencies involving palliative care patients.

METHODS

For data collection an open discussion of the main topics by experts in palliative and emergency medical care was employed. Main outcome measures and recommendations included responses regarding current practices related to expert opinions and international literature sources.

RESULTS

As the essential points of consensus the following recommendations for optimization of care were named: (1) integration of palliative care in the emergency medicine curricula for pre-hospital emergency physicians and paramedics, (2) development of outpatient palliative care, (3) integration of palliative care teams into emergency medical structures, (4) cooperation between palliative and emergency medical care, (5) integration of crisis intervention into outpatient palliative emergency medical care, (6) provision of emergency plans and emergency medical boxes, (7) provision of palliative crisis cards and do not attempt resuscitation (DNAR) orders, (8) psychosocial aspects concerning palliative emergencies and (9) definition of palliative patients and their special situation by the physician responsible for prior treatment.

CONCLUSIONS

Prehospital emergency physicians are confronted with emergencies in palliative care patients every day. In the treatment of these emergencies there are potentially serious conflicts due to the different therapeutic concepts of palliative medical care and emergency medical services. This study demonstrates that there is a need for regulated criteria for the therapy of palliative patients and patients at the end of life in emergency situations. Overall, more clinical investigations concerning end-of-life care and unresponsive palliative care patients in emergency medical situations are necessary.

[The (non)sense of certification in intensive care medicine. The problem of the detection of suitable indicator systems]

Certification is a compulsory element of today's quality management. However, the instruments used for certification have mostly originally been developed for industrial purposes. Even with tried and tested adaptation to hospital structures, transferring these instruments to the medical environment implies partial negligence of outcome quality. This fact is due to the multidimensional structure of medical outcome quality, which cannot be reduced to only one indicator. This review describes the necessity to develop a specific indicator system, which is needed for an objective, reliable and valid system of certification for intensive care units. The second part of the review describes the current efforts which are being undertaken to develop such a certification system for German intensive care units. Until this new system has been validated, certification of intensive care units is of limited value for evaluating the quality of intensive care units in Germany.

Xenon anesthesia impairs hepatic oxygenation and perfusion in healthy pigs

BACKGROUND

Over the last 15 years, there has been growing interest in the noble gas xenon as a new inhalational anesthetic. This is due to its favorable pharmacological properties such as short onset and offset, as well as its hemodynamic stability. However, most volatile anesthetics appear to play an important role in the multi-factorial etiology of perioperative liver injury by decreasing liver blood flow with a subsequent reduction of hepatic oxygen supply. However, the effects of the anesthetic gas xenon on hepatic perfusion and oxygenation have not been completely investigated.

METHODS

Following ethical approval, 18 anesthetized and acutely monitored pigs were randomly assigned to the two following groups: 9 animals received xenon anesthesia in increasing inspiratory concentrations of 0%, 20%, 50%, and 65% in addition to their basic intravenous anesthesia; 9 animals served as a control group. Measurement points for systemic and regional hemodynamic and oxygenation parameters were performed 30 min after changing the xenon concentration.

RESULTS

Xenon elicited dose-dependent systemic hemodynamic changes such that the mean arterial pressure did not change, while the heart rate and cardiac output decreased by about 30%, thereby indicating an increase in the systemic vascular resistance. Portal venous blood flow decreased, while hepatic arterial blood flow was unchanged. The oxygen supply of the liver was reduced, but not the rate of indocyanine plasma disappearance from the liver. Furthermore, the increase of liver surface pO2 to systemic hyperoxia was absent, and hepatic lactate uptake was reduced.

CONCLUSION

Xenon, in addition to basic intravenous anesthesia, elicited a decrease in heart rate and cardiac output and an increase in mean arterial pressure. Similar to volatile anesthetics, xenon does reduce portal venous flow and influences hepatic tissue oxygenation. In contrast, hepatic arterial blood flow remains stable in the presence of xenon, and no changes in the hepatic arterial buffer responses were evident. Xenon does affect hepatic perfusion and oxygenation.

Einfluss der Clonidin-induzierten systemischen Sympathikolyse auf die Oxygenierung und Perfusion der Leber

BACKGROUND

Increased sympathetic nervous activity which induces vasoconstriction and decreases perfusion may be an underlying mechanism behind the development of perioperative liver damage. This animal study was designed to assess how clonidine-induced systemic sympathicolysis affects liver oxygenation with respect to induced hypotension and vasodilatation under physiological conditions.

METHODS

Following ethical approval 17 anesthetized and acutely instrumented pigs were randomly assigned to 2 groups. Group 1 consisted of 8 animals receiving intravenous clonidine (2 microg x kg(-1) bolus and 2 microg x kg(-1) x h(-1) for induction of sympathicolysis and group 2 consisted of 9 animals serving as controls. After obtaining baseline values, measurements were repeated 90 and 250 min after starting to reduce systemic sympathetic nervous activity.

RESULTS

Clonidine-induced systemic sympathicolysis was associated with decreased mean arterial blood pressure, cardiac output and heart rate. Portal venous and hepatic arterial blood flow, oxygen delivery to the liver, oxygen uptake and liver tissue oxygen partial pressure remained unchanged. The plasma indocyanine green disappearance rate increased.

CONCLUSION

We concluded that despite decreased mean arterial pressure and cardiac output, clonidine-induced systemic sympathicolysis did not affect liver oxygenation or perfusion.

[Fever in intensive care patients]

Fever is an unspecific symptom of most intensive care patients during their stay on an intensive care unit. The reasons for the increase of body temperature often remain unclear, even extended diagnostic measures are performed. The pathogenetic relevance of fever is commonly underestimated and leads to unreflected treatment of every increase of body temperature above 38 C. But the development of fever in patients is quite often useful and should not be treated with antipyretics. Physical measures like ice packs and surface cooling are only allowed to be used, if the central set point is lower than the actual core body temperature. This gradient can be recognized, when the patient starts to sweat. Principally, the treatment of fever in cardiovascular risk patients, patients with high risk for adverse neurological outcome, pregnant women during the first trimenon and in children with seizures must start with pharmacological interventions,which can be followed by physical measures.

Protective effects of PARP inhibition on liver microcirculation and function after haemorrhagic shock and resuscitation in male rats

OBJECTIVE

The aim of this study was to investigate the impact of the water-soluble poly-(ADP)-ribose-polymerase (PARP) inhibitor 5-aminoisoquinolinone (5-AIQ) on liver microcirculation and function after haemorrhagic shock and resuscitation.

DESIGN

Controlled, randomized animal study.

SETTING

University animal care facility and research laboratory.

SUBJECT

Male Sprague-Dawley rats were subjected to haemorrhagic shock for 1 h, followed by resuscitation with shed blood and crystalloid solution for a total of 5 h.

INTERVENTIONS

The PARP inhibitor 5-AIQ (3 mg/kg; n=7) or vehicle (n=7) was administered 5 min prior to resuscitation. Sham-operated animals without induction of shock served as controls (n=7).

MEASUREMENTS AND RESULTS

Using intravital fluorescence microscopy hepatic microcirculation was assessed at baseline, end of shock phase as well as 1 h and 5 h after resuscitation. Systemic arterial blood pressure and bile flow were continuously monitored. 5-AIQ treatment attenuated shock/resuscitation-induced increase of intrahepatic leukocyte-endothelial cell interaction with a marked reduction of both sinusoidal leukostasis and venular leukocyte adherence. Moreover, nutritive perfusion was found improved, guaranteeing sufficient oxygen supply to tissue, as indicated by low NADH autofluorescence, which was not different to that in controls. Most notably, excretory liver function reached baseline level over 5 h of reperfusion in 5-AIQ-treated animals.

CONCLUSIONS

In the present setting of shock/resuscitation in male rats the PARP inhibitor 5-AIQ proved to be very effective in ameliorating compromised liver microcirculation and function. Further research has to confirm that PARP inhibition is a suitable tool in the acute treatment of patients suffering from reduced circulating blood volume and thus microcirculatory organ dysfunction.

Comparison of invasive and less-invasive techniques of cardiac output measurement under different haemodynamic conditions in a pig model

BACKGROUND AND OBJECTIVE

Despite the introduction of various less-invasive concepts of cardiac output measurement, pulmonary arterial thermodilution is still the most common measurement technique.

METHODS

This prospective controlled study was designed to compare different methods of cardiac output measurement simultaneously. Pulmonary arterial thermodilution, transpulmonary thermodilution (PiCCO), trans-oesophageal echo-Doppler probe (HemoSonic) and partial carbon dioxide rebreathing technique (NICO monitor) were evaluated against a peri-aortic transit-time flow-probe as reference method in a clinically relevant animal model. After approval from the Local Ethics Committee on Animal Research, the investigations were conducted in nine anesthetized domestic pigs. Systemic haemodynamics were modulated systematically by the application of catecholamines, caval occlusion and exsanguination. Statistical analysis was performed with Bland-Altman and linear regression.

RESULTS

A total of 366 paired cardiac output measurements were carried out at a reference cardiac output between 0.5 and 7 L min(-1). The correlation coefficients for pulmonary arterial and transpulmonary thermodilution against reference were 0.93 and 0.95, for trans-oesophageal Doppler and partial rebreathing technique 0.84 and 0.77. Pulmonary arterial thermodilution and transpulmonary thermodilution showed comparable bias and limits of agreement. Where HemoSonic showed an overestimation of cardiac output at a higher precision, NICO overestimated low and underestimated higher cardiac output values.

CONCLUSIONS

Our data suggest that pulmonary arterial thermodilution and PiCCO may be interchangeably used for cardiac output measurement even under acute haemodynamic changes. The method described by Bland and Altman demonstrated an overestimation of cardiac output for both thermodilution methods. HemoSonic and NICO offer non-invasive alternatives and complementary monitoring tools in numerous clinical situations. Trend monitoring and haemodynamic optimizing can be applied sufficiently, when absolute measures are judged critically in a clinical context. The use of the NICO system seems to be limited during acute circulatory changes.

[Toxic-shock-like-syndrome caused by beta-hemolysing group G streptococci in a multimorbid patient with erysipelas]

HISTORY AND FINDINGS

A 41-year-old, obese man with a history of incomplete paraplegia of both legs and chronic venous insufficiency with stasis dermatitis presented with acute respiratory and hyperdynamic hemodynamic failure. He was transferred from another hospital to the department of intensive care medicine for further diagnosis and treatment. A livid coloured, necrotizing-hemorrhagic swelling of the right lower leg was noted.

INVESTIGATIONS

Laboratory tests revealed an inflammation probably due to bacterial infection, anemia, acute renal failure, acute hepatic dysfunction, coagulopathy and lactic acidosis, indicating multi-organ failure and septic shock. No focus of sepsis was found at abdominal sonography and exploratory laparotomy. Chest X-Ray and computed tomography revealed bilateral pneumonia. Doppler ultrasonography of both legs showed acute isolated thrombosis of the right posterior tibial vein.

TREATMENT AND COURSE

In addition to a chronic venous ulcer-necrotizing hemorrhagic erysipelas had developed in the right lower leg. A swab taken at surgery and blood cultures grew Streptococcus dysgalactiae ssp. equisimilis (group G streptococci, GGS). Despite intensive care treatment and high dosage penicillin G therapy the patient died two days after admission from septic shock and multi-organ failure.

CONCLUSIONS

Group G streptococci cause a variety of common and severe infections. Erysipelas is infrequently associated with GGS but, much more often, with group A streptococci (GAS). This unusual and fulminant case emphasizes the importance of considering Streptococcus dysgalactiae as a causative agent in septicemia with multiple predisposing factors and soft-tissue infections.

Effects of systemically applied clonidine on intestinal perfusion and oxygenation in healthy pigs during general anaesthesia and laparotomy 1

BACKGROUND AND OBJECTIVE

Clonidine, which is used for induction of sympatholysis and prevention or treatment of alcohol withdrawal in anaesthesia and intensive care medicine, may have deleterious effects on intestinal mucosal perfusion. This study was designed to investigate the effects of clonidine on intestinal perfusion and oxygenation.

METHODS

Following ethical approval 17 anaesthetized, and acutely instrumented pigs were randomly assigned to two groups: eight animals received intravenous clonidine (2 microg kg(-1) bolus and 2 microg kg(-1) h(-1)), nine animals served as a control group. Measurement points for systemic and regional haemodynamic and oxygenation parameters were 135 and 315 min after starting the clonidine application.

RESULTS

Clonidine elicited systemic haemodynamic changes (median [25-75th interquartile range]): heart rate (106 [91, 126] to 84 [71, 90] beats min(-1)) cardiac output (147 [123, 193] to 90 [87, 107] mL min(-1) kg(-1)) and mean arterial pressure (77 [72, 93] to 69 [61, 78] mmHg) decreased. Despite systemic haemodynamic changes, the superior mesenteric artery blood flow did not change in the clonidine group. The vascular resistance of the superior mesenteric artery decreased. The small intestinal oxygen supply, the mucosal and the serosal tissue oxygen partial pressure did not change.

CONCLUSIONS

Systemic sympatholysis induced by intravenously applied clonidine in addition to basic intravenous anaesthesia elicited a decrease in cardiac output and mean arterial pressure. However, regional macrohaemodynamic perfusion was maintained and intestinal oxygenation did not change. Clonidine does not impair intestinal mucosal and serosal oxygenation under physiological conditions.

Effects of xenon anaesthesia on intestinal oxygenation in acutely instrumented pigs

BACKGROUND

Xenon is a narcotic gas that might be able to replace volatile anaesthetics or nitrous oxide due to its favourable pharmacological properties, such as providing haemodynamic stability. Intestinal oxygenation is affected by most volatile anaesthetics as a result of cardiodepressive effects. Reducing oxygenation of the gut might be a factor leading to perioperative organ dysfunction. This animal study was designed to assess the effects of xenon on intestinal oxygenation.

METHODS

After ethical approval, 24 anaesthetized, acutely instrumented pigs were randomly assigned to three groups: nine animals received xenon anaesthesia with inspiratory concentrations of 0, 20, 50 and 65% in addition to their basic i.v. anaesthesia, nine animals served as a study control group, and five animals were used to assess model stability. Measurement of systemic and regional haemodynamic and oxygenation parameters was made 30 min after changing the xenon concentration.

RESULTS

Xenon elicited dose-dependent systemic haemodynamic changes: heart rate and cardiac output decreased by 30%, while mean arterial pressure was stable. Superior mesenteric artery blood flow was lower in the xenon group. Vascular resistance of the superior mesenteric artery increased. The small intestinal oxygen supply decreased with increasing xenon concentration; the mucosal tissue oxygen partial pressure decreased but did not reach hypoxic (<5 mm Hg) values. Serosal tissue oxygen partial pressure was maintained.

CONCLUSIONS

Xenon, in addition to basic i.v. anaesthesia, elicited a decrease in cardiac output and maintained mean arterial pressure. Intestinal oxygenation was maintained, although regional macrohaemodynamic perfusion decreased. Xenon does not impair intestinal oxygenation under physiological conditions.

[Alcohol--a perioperative problem of anaesthesia and intensive care medicine]

Alcohol is a socially tolerated drug. Its consumption is associated with several physiological and pharmacological negative side-effects during anaesthesia and intensive care. The impact of chronic and acute alcoholism on perioperative morbidity and mortality and especially on anaesthetic risk are important, due to pharmacological interactions, pathophysiological changes and direct pharmacological interactivities between alcohol and narcotics. In contrast to opioid withdrawal symptoms of alcohol withdrawal are a serious and potentially life-threatening complication and should be avoided or the risk for occurrence must at least be reduced. Patients with a high risk of developing perioperative symptoms of alcohol withdrawal can be detected by laboratory tests and questionnaires. A prophylaxis of withdrawal should be started preoperatively solely with benzodiazepines or in combination with clonidine. Haloperidol is the drug of choice for emerging symptoms of alcohol withdrawal with productive psychosis. To estimate the pharmacological changes during anaesthesia, it is necessary to differentiate whether the patient is an occasional drinker with acute intoxication, a chronic abuser without limitations of hepatic function or a chronic user with insufficiency of the liver. The most important implication for anaesthesia are the choice of a rapid sequence induction to reduce the risk of aspiration and the maintenance of haemodynamic stability and liver perfusion. For the acute alcoholic providing prolonged postoperative surveillance is necessary, for the chronic alcoholic intensive care seems to be mandatory. For regional anaesthesia the indications and limitations are the same as for other patients (cooperativeness, coagulation, consent, etc.).

[Perioperative management of a patient with Sneddon syndrome--a case report]

Sneddon's syndrome is a rare combination of generalised livedo reticularis and cerebrovascular accidents. Its clinical presentation varies widely and its aetiology is still not known. 60 to 80% of patients are female. First symptoms of the syndrome are mostly repetitive cerebral strokes, but reduced perfusion of the skin, seen as blue or red-brown mottling, precedes the strokes. The vascular disease is generalised and often accompanied by arteriosclerosis, systemic arterial hypertension, valvular heart disease and the presence of antiphospholipid antibodies. The diagnostic procedures are complicated and have to exclude other autoimmunological diseases. Therapeutic options are anticoagulatory therapy with warfarin, ASS or heparin, reduction of endothelial proliferation with ACE-inhibitors, and improvement of microvascular perfusion with prostaglandine. The increased anaesthesiological risk with these patients is due to the acute risk of thromboembolism and ischaemic cerebral and cardiovascular insults. The anaesthetic management must provide stable perfusion pressures for cerebral and myocardial arteries and avoid increasing risk factors for thromboembolism such as increased blood viscosity or stasis due to improper positioning of the patient. The choice of anaesthetic drugs is dependent on good controllability for haemodynamic stability. The high risk of patients with Sneddon's syndrome justifies a more invasive haemodynamic monitoring and postoperative surveillance on an intensive care unit. This case report describes the anaesthesiological considerations for, and management of, a patient with Sneddon's syndrome who was admitted to hospital for vaginal hysterectomy.

[Intraoperative ventricular fibrillation in a patient with chronic cocaine abuse--a case report]

With increasing drug abuse of cocaine, the chances are growing that an anaesthetist comes into contact with an acutely intoxicated patient or chronic cocaine user while on call or during his daily routine. In South America chewing coca leaves is daily practise, while in the industrialised world the drug is sniffed, smoked or injected intravenously. Clinically, cocaine is used topically in ENT and ophthalmology due to its local analgesic and strong vasoconstrictive properties. Cocaine has a similar effect on the CNS as amphetamines and produces euphoria and hallucinations. Cocaine acts indirectly on sympathetic stimulation, release of dopamine and inhibition of catecholamine metabolism. It is metabolised in the liver and by serum esterases. Intoxication with cocaine leads to respiratory depression, arrhythmias, ventricular fibrillation and death. If an emergency operation during acute cocaine intoxication is necessary, all sympathomimetic anaesthetic drugs must be avoided. A deep anaesthesia must be provided to reduce the risk of cardiovascular complications. In the literature, anaesthesia is regarded as safe for patients with chronic cocaine misuse after abstinence of 24 hours. This case report shows that, even without acute intoxication, severe cardiovascular problems are possible in patients with chronic cocaine abuse. Hence, we recommend a cocaine-free interval of at least one week before elective surgical procedures.

[Remifentanil analgesia for aspiration of follicles for oocyte retrieval]

Remifentanil is an esterase-metabolized ultra-short acting mu-agonist opioid with a rapid clearance. The aim of this study was to determine the efficacy of remifentanil infusion for the short-lasting, but painful, transvaginal puncture for oocyte retrieval. Eighty consenting adult women (ASA I and II) aged 30.5 +/- 5 years and with a body weight of 69.1 +/- 9.1 kg were enrolled in this prospective study. After an oral premedication with 7.5 mg midazolam, all patients received 3 l/min oxygen. Subsequently, the remifentanil infusion was started with a rate of 0.3 microg/kg/min. Remifenanil doses were adjusted as needed for painless puncture and sufficient oxygen saturation in steps of 0.05 microg/kg/min. Dosage requirements, blood pressure, heart rate, oxygen saturation (pulse oxymetry, SaO2) and the level of analgesia were recorded every 3 minutes. Follicular aspiration lasted 11.8 +/- 4.1 min and the time of remifentanil infusion was 18.7 +/- 4.6 min. Dosage requirements of remifentanil were 0.3 microg/kg/min in 48.7% of all patients, but 27.8% needed only 0.25 microg/kg/min and 16.6% needed only 0.2 microg/kg/min. However, 4.2% of patients needed 0.35 microg/kg/min and 2.7% of all cases needed 0.4 microg/kg/min. Vital parameters remained nearly unchanged. Oxygen saturation decreased significantly from 99.2 +/- 0.7% to 98.2 +/- 2.4% after 3 min and to 94.9 +/- 7.2% after 10 min. Nine women showed motoric reactions to puncture. In many cases, the infusion of remifentanil after premedication with midazolam provided a suitable and satisfying anaesthesia for oocyte retrieval. Some patients, however, showed motoric reactions to vaginal puncture, while in other cases significant and clinical relevant decreases in Hb-oxygen saturation occurred. Therefore, we no longer carry out remifentanil infusion for transvaginal oocyte retrieval. We now prefer a remifentanil infusion of 0.2 microg/kg/min and propofol (1 mg/kg initially with intermittent doses of 0.5 mg/kg) combined with assisted ventilation by mask.

[Perioperative management of a patient with alcaptonuria--a case report]

Alcaptonuria is a very rare enzymatic disease with a compromised degradation of the amino acids phenylalanine and tyrosine. As a consequence, homogentisic acid accumulates, most of which is cleared by the kidneys. In time, homogentisic acid forms black pigment, which accumulates throughout the body in connective tissue such as cartilage and joints. Apart from superficial discoloration, the most clinical manifestation of the disease is arthropathy, starting in middle age. From the anaesthesiologist's point of view, there is a severe risk of difficult airway because of an advanced stiffness of the cervical spine and a reduced mouth opening in these patients. Due to deformity and stiffness of the spine, difficulties in spinal and epidural anaesthesia must be reckoned with. A further risk for patients with alcaptonuria is cardiac involvement, which occurs later than degenerative changes of the joints. The accumulated pigment most likely adds to the development of degenerative changes of the valve and coronary artery disease and there is an increased risk of developing aneurysms in atherosclerotic altered vessels. Therefore, at the preoperative visit a thorough clinical cardiovascular examination should be performed. Cardiological advice and an examination should be sought from a specialist. For intubation, fibreoptic procedures should be considered. Anaesthetic management and perioperative monitoring are determined by the results of the cardiological examination and the type and extent of the operation.

[Cricoid pressure--safety necessity or unnecessary risk?]

Cricoid pressure is a simple and effective measure to prevent regurgitation of gastric juice and content. This procedure, which prevents a possible reflux by compression of the oesophagus between the cricoid cartilage and the cervical vertebral bodies, is generally acknowledged in clinical practice, although there is lack of scientific evidence regarding its effect on the outcome of patients at risk of aspiration. However, there is only a rare incidence of complications as long as cricoid pressure is used with exact indication, considering the contraindications and correct performance. Especially important are the optimal force applied on the cricoid and the duration of application. However, there is a lot of evidence in the literature that the knowledge of anaesthetists about the method and technique of cricoid pressure is rather unsatisfactory. Thus, the starting point for improving the efficiency and safety of cricoid pressure seems to be better teaching and training.

[Managing anesthesia in the alcoholic patient]

In most developed countries, alcohol is a socially tolerated drug. Nevertheless, its consumption is associated with several negative side-effects during anaesthesia. In surgical patients the prevalence of alcoholism exceeds 20%. Chronic alcoholism and acute alcoholism have an important impact on perioperative morbidity and mortality and especially on anaesthetic risk, due to pharmacological interactions, pathophysiological changes and direct pharmacological interactivities between alcohol and narcotics. Symptoms of alcohol withdrawal are a serious and potentially life-threatening complication and should be avoided or the risk for occurrence should at least be reduced. Patients with a high risk of developing perioperative symptoms of alcohol withdrawal can be detected by laboratory tests and questionnaires. The most important implication for anaesthesia is the choice of a rapid sequence induction to reduce the risk of aspiration and the maintenance of haemodynamic stability and liver perfusion. Maintaining body temperature and providing intensive postoperative surveillance and care are necessary. The indications for regional anaesthesia are the same as for other patients (cooperativeness, coagulation, consent, etc.). In general, awareness of possible interactions can reduce perioperative complications and improve postoperative outcome.

Effects of epidural anaesthesia on intestinal oxygenation in pigs

BACKGROUND

Perioperative intestinal hypoperfusion is a major contributing factor leading to organ dysfunction. It can be caused by stress as a result of surgical manipulation or hypoxia. Additionally, anaesthesia can affect intestinal oxygenation. This animal study was designed to assess the effects of reduced regional sympathetic nervous activity induced by thoracic epidural anaesthesia on intestinal oxygenation.

METHODS

After ethical approval, 16 anaesthetized and acutely instrumented pigs were randomly assigned to two groups (epidural anaesthesia alone vs epidural anaesthesia plus volume loading). The epidural anaesthesia aimed for a T5-T12 block. Measurements were at baseline and after 1 and 2 h.

RESULTS

Epidural anaesthesia was associated with a decrease in mean arterial blood pressure and pronounced mesenteric vasodilatation. Mesenteric blood flow did not change. Intestinal oxygen uptake, mucosal tissue oxygen partial pressure and tissue carbon dioxide partial pressure remained unchanged.

CONCLUSIONS

Despite marked systemic hypotension, epidural anaesthesia did not affect intestinal oxygenation. There was no benefit obtained from volume loading.

[Smoking and preoperative fasting--are there evidence-based guidelines?]

Over the last years several clinical studies have modified the guidelines for preoperative fasting to reduce the risk of pulmonary aspiration. In most western countries the following guidelines are accepted: for clear liquids 2 hours, breast feeding 4 hours, small meals and breast milk substitutes 6 hours, heavy meals 8 hours. Since preoperative smoking is acknowledged as a risk factor, it should be ceased in most clinics 6 hours before induction of anaesthesia, as well. Smoking, however, does not increase the risk of pulmonary aspiration, as is often maintained, but increases the risk of postoperative pulmonary complications. To reduce the risk of perioperative pulmonary complications, cessation of smoking is necessary 8 weeks before operation. Stopping smoking only a few days before operation and anaesthesia even tends to increase the risk of pulmonary complications. Regarding cardiac complications, cessation of smoking 12 hours before anaesthesia is sufficient to reduce the incidence of cardiac ischaemia.

[Hemodynamic monitoring of splanchnic circulation--does the benefit outweight risk of of regional circulation monitoring?]

Over the last 20 years there has been increasing interest in the pivotal role of the splanchnic region in the development of SIRS, sepsis and multiple organ failure. One key question is how to monitor and detect in good time regional splanchnic perfusion, oxygenation and impaired function of liver and gut, so as to start appropriate therapeutic measures. This review describes the pathophysiological background of impaired splanchnic perfusion. It focuses on the advantages and risks of methods of monitoring splanchnic perfusion or oxygenation and considers them regarding clinical relevance and usefulness. Special emphasis is laid on gastric tonometry. Despite all the restrictions and the criticism which can be levelled at this method, it remains the only way of monitoring splanchnic perfusion and oxygenation that is currently applicable in clinical routine. The data gained can be useful if clinicians are aware of the weak points of tonometry and consider the data in the overall clinical picture. When this is done, the patient can profit from gastric tonometry and the benefits outweigh the risks.

Analysis of volatile disease markers in blood

BACKGROUND

The diagnostic potential of breath analysis has been limited by a lack of knowledge on origin, distribution, and metabolism of the exhaled substances. To overcome this problem, we developed a method to assess trace amounts of hydrocarbons (pentane and isoprene), ketones (acetone), halogenated compounds (isoflurane), and thioethers (dimethyl sulfide) in the blood of humans and animals.

METHODS

Arterial and venous blood samples were taken from mechanically ventilated patients. Additional blood samples were taken from selected vascular compartments of 19 mechanically ventilated pigs. Volatile substances were concentrated by means of solid-phase microextraction (SPME), separated by gas chromatography, and identified by mass spectrometry.

RESULTS

Detection limits were 0.02-0.10 nmol/L. Venous concentrations in pigs were 0.2-1.3 nmol/L for isoprene, 0-0.3 nmol/L for pentane, and 1.2-15.1 nmol/L for dimethyl sulfide. In pigs, substances were not equally distributed among vascular compartments. In humans, median arteriovenous concentration differences were 3.58 nmol/L for isoprene and 1.56 nmol/L for pentane. These values were comparable to pulmonary excretion rates reported in the literature. Acute respiratory distress syndrome (ARDS) patients had lower isoprene concentration differences than patients without ARDS.

CONCLUSIONS

The SPME method can detect volatile substances in very low concentrations in the blood of humans and animals. Analysis of volatile substances in vascular compartments will enlarge the diagnostic potential of breath analysis.

Effect of nitric oxide on shock-induced hepatic heme oxygenase-1 expression in the rat

Recent evidence suggests that the hepatic expression of heme oxygenase-1 (HO-1) may preserve hepatocellular integrity after hemorrhagic shock and resuscitation (HR). Because nitric oxide (NO) has been shown to modulate HO-1 expression in cultured cells in vitro, we determined its potential role in the regulation of HO-1 expression after HR in the rat liver in vivo. HO-1 mRNA and protein were highly induced and HO enzyme activity was higher after HR when compared with time-matched sham controls. Administration of the NO donor, molsidomine (MOL) (3 mg. kg(-1)), during resuscitation attenuated the accumulation of HO-1 mRNA and protein and the rise in HO activity. In addition, MOL prevented the shock-induced increase in DNA binding activity of the transcription factor, activator protein-1 (AP-1), but did not alter the activity of nuclear factor-erythroid 2 related factor (Nrf-2), nuclear transcription factor-kappaB (NF-kappaB), and hypoxia-inducible factor-1 (HIF-1). The suppressing action of MOL was not confined to HO-1, because the hepatic expression of the 70-kd major heat shock protein (HSP) in response to HR was also diminished. Moreover, MOL prevented the HR-induced increase in the serum activity of alanine transaminase (ALT) and alpha-glutathione-S-transferase (alpha-GST) that could otherwise be observed after HR. In contrast, the NO synthase inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME) (1 mg.kg(-1)), had either no or only minor effects on the primary experimental endpoints. These findings would be consistent with a reduction of shock-induced liver damage by exogenous NO, which in turn prevents the subsequent activation of injury-sensitive transcription factors, thus attenuating the expression of stress-inducible proteins such as HO-1.

The uptake of sevoflurane during anaesthesia

The rate of uptake of sevoflurane during clinical anaesthesia (1.3 MAC) was measured by computer-controlled injection of liquid anaesthetic into a closed breathing system. The cumulative uptake of sevoflurane was 4.8 ml, 7.4 ml, 9.5 ml and 11.5 ml at 30, 60, 90 and 120 min, respectively. The ratio of inspired to end-expired sevoflurane was greater than similar measurements we have made for desflurane in the past, but the absolute rate of sevoflurane uptake was less than the rate of uptake of desflurane in these cases. The rate of uptake was equivalent to 059e-0.32t + 0.039e-0.036t + 0.105e-0.0034t ml.min-1 liquid sevoflurane. Plasma urea and creatinine measured on the first postoperative day were not significantly different from pre-operative values.

The loss of sevoflurane from a closed breathing system

When volatile anaesthetics are used in a closed breathing system it is usually assumed that inflow of anaesthetic to the system matches uptake by the patient. Early laboratory reports on the interactions between sevoflurane and soda lime cast doubt on that assumption. We have measured the loss of sevoflurane, desflurane and isoflurane from a closed breathing system and found no differences of consequences.