Implementation of anesthesia quality indicators in Germany : A prospective, national, multicenter quality improvement study.

BACKGROUND: In 2016 the German Society of Anesthesiology and Intensive Care Medicine (DGAI) and the Association of German Anesthetists (BDA) published 10 quality indicators (QI) to compare and improve the quality of anesthesia care in Germany. So far, there is no evidence for the feasibility of implementation of these QI in hospitals. OBJECTIVE: This study tested the hypothesis that the implementation of the 10 QI is feasible in German hospitals. MATERIAL AND METHODS: This prospective three-phase national multicenter quality improvement study was conducted in 15 German hospitals and 1 outpatient anesthesia center from March 2017 to February 2018. The trial consisted of an initial evaluation of pre-existing structures and processes by the heads of the participating anesthesia departments, followed by a 6-month implementation phase of the QI as well as a final re-evaluation phase. The implementation procedure was supported by web-based implementation aids ( www.qi-an.org ) and internal quality management programs. The primary endpoint was the difference in the number of implemented QI per center before and after implementation. Secondary endpoints were the number of newly implemented QI per center, the overall number of successful implementations of each QI, the identification of problems during the implementation as well as the kind of impediments preventing the QI implementation. RESULTS: The average number of implemented QI increased from 5.8 to 6.8 (mean of the differences 1.1 ± 1.3; P < 0.01). Most frequently the QI perioperative morbidity and mortality report (5 centers) and the QI temperature management (4 centers) could be implemented. After the implementation phase, the QI incidence management and patient blood management were implemented in all 16 centers. Implementation of other quality indicators failed mainly due to a lack of time and lack of structural resources. CONCLUSION: In this study the implementation of QI was proven to be mostly feasible in the participating German hospitals. Although several QI could be implemented with minor effort, more time, financial and structural resources would be required for some QI, such as the QI postoperative visit.

[Implementation of anesthesia quality indicators in Germany : A prospective, national, multicenter quality improvement study]. / Implementierung anästhesiologischer Qualitätsindikatoren in Deutschland : Eine prospektive, nationale, multizentrische Qualitätssteigerungsstudie German version.

BACKGROUND: In 2016 the German Society of Anesthesiology and Intensive Care Medicine (DGAI) and the Association of German Anesthetists (BDA) published 10 quality indicators (QI) to compare and improve the quality of anesthesia care in Germany. So far, there is no evidence for the feasibility of implementation of these QI in hospitals. OBJECTIVE: This study tested the hypothesis that the implementation of the 10 QI is feasible in German hospitals. MATERIAL AND METHODS: This prospective three-phase national multicenter quality improvement study was conducted in 15 German hospitals and 1 outpatient anesthesia center from March 2017 to February 2018. The trial consisted of an initial evaluation of pre-existing structures and processes by the heads of the participating anesthesia departments, followed by a 6-month implementation phase of the QI as well as a final re-evaluation phase. The implementation procedure was supported by web-based implementation aids ( www.qi-an.org ) and internal quality management programs. The primary endpoint was the difference in the number of implemented QI per center before and after implementation. Secondary endpoints were the number of newly implemented QI per center, the overall number of successful implementations of each QI, the identification of problems during the implementation as well as the kind of impediments preventing the QI implementation. RESULTS: The average number of implemented QI increased from 5.8 to 6.8 (mean of the differences 1.1 ± 1.3; P < 0.01). Most frequently the QI perioperative morbidity and mortality report (5 centers) and the QI temperature management (4 centers) could be implemented. After the implementation phase, the QI incidence management and patient blood management were implemented in all 16 centers. Implementation of other quality indicators failed mainly due to a lack of time and lack of structural resources. CONCLUSION: In this study the implementation of QI was proven to be mostly feasible in the participating German hospitals. Although several QI could be implemented with minor effort, more time, financial and structural resources would be required for some QI, such as the QI postoperative visit.

[The COVID-19 pandemic had significant impact on duration of surgery and hospitalization time for patients after cholecystectomy]. / Die Auswirkungen der COVID-19 Pandemie führten zu signifikanten Veränderungen der Operations- und Liegezeiten bei Patienten nach Cholezystektomie.

BACKGROUND: The COVID-19 pandemic made substantial changes in medical care necessary. The aims of this study were to find out what influence the pandemic had on the perioperative course in patients with cholecystectomy (CHE) and to highlight possible residual consequences. METHOD: From 1 July 2018 to 31 December 2021 a total of 735 patients with CHE were analyzed. Up to 21 March 2020 patients were assigned to the regular patient group (Reg, n = 430), patients after this date (first lockdown 22 March 2020) to the Cov19 patient group (Cov19, n = 305) and the 2 groups were compared. RESULTS: The average age of all patients was 59 years and 63% were women. The average length of hospitalization (KrVD, time period between surgery and discharge) was 4.4 days. The patient groups Reg and Cov19 did not differ with respect to age, gender or KrVD. The total number of CHEs carried out was reduced by 21.4% in the Cov19 group. This affected elective and emergency CHE to the same extent. The length of surgery significantly increased in the Cov19 group from 64 min (SD 34 min) to 71 min (SD 38 min). The number of short and long hospital stays (KrVD 2 or >4 days) significantly increased in the Cov19 group from 4 % to 20 % (short stay, p < 0.01) and from 23 % to 27 % (long stay, p < 0.01). This was particularly observed for patients >70 years old with an increase in long stays from 43 % to 56 % in the Cov19 group. CONCLUSION: The COVID-19 pandemic led to a clear reduction in CHE both for elective and emergency interventions. Furthermore, a significant lengthening of the surgery and hospitalization times could be observed for older patients. The residual consequences of the pandemic could be shortened hospitalization times after uncomplicated CHE and more interventional treatment procedures in complex cases.

Non-absorbable interrupted versus absorbable continuous skin closure in pediatric appendectomies.

BACKGROUND AND AIMS: appendectomy wounds are still commonly closed with non-absorbable sutures. Stitch removal has financial costs and causes anxiety in children. Our aim was to compare interrupted non-absorbable (NA) and continuous intradermal absorbable (A) sutures in appendectomy wounds to evaluate whether absorbable suturing increases the risk of complications. MATERIAL AND METHODS: 198 children (age 4-18 years) including perforated cases were prospectively randomized into two groups (NA and A skin closure). The wounds and inflammatory markers were evaluated on the first two postoperative days. The appearance of the wound was evaluated one week postoperatively by a district nurse. Follow-up data were obtained from 166 patients (87 in NA group and 79 in A group). RESULTS: in NA group 86 % and in A group 81 % had appendicitis (8 % and 15.6 % perforated and 9.3 % and 25 % gangrenous cases in NA and A groups, respectively). The total wound infection rate was low, 1.8 % (2.3 % in NA Group and 1.3% in A Group). No differences in the inflammatory markers or the appearance of the wound were noted between the groups, but nine children in NA Group (10.3 %) had a partial wound dehiscence after stitch removal. CONCLUSION: appendectomy wounds in children can be closed with continuous, absorbable sutures, even in complicated cases.

[Fibrodysplasia ossificans progressiva. Anesthetic management of a 2-year-old child]. / Fibrodysplasia ossificans progressiva. Anästhesiologische Versorgung eines 2-jährigen Jungen.

Fibromyalgia ossificans progressiva (FOP) is a severely disabling disorder of connective tissue characterized by congenital malformation of the toes, fingers and vertebrae associated with progressive ossification of striated muscles. Anesthetic management of these patients involves preferably general anesthesia as local or regional anesthesia should be avoided due to possible heterotopic ossification. Airway management is determined by the age of the patient and the progression of the disease. Only a few cases in the literature have reported the anesthetic management of FOP patients and to our knowledge only one case has been published on pediatric patients. In adult, cooperative patients awake fiberoptic intubation is recommended, as ankylosis of the temporo-mandibular joint is the most important clinical feature for anesthesia. As demonstrated and discussed in this case report of a 2-year-old boy, fiberoptic intubation after induction of general anesthesia should be preferred in pediatric patients. Puncture of a vein should be non-traumatic, i.m. injections strictly avoided and careful positioning and padding are needed. Every effort should be made to avoid situations stimulating new heterotopic ossification due to its substantial effect on the quality of life of FOP patients.

Perforation of the upper and lower segments of atretic esophagus (type C) secondary to nasogastric tube insertion.

We report an unusual case of nasogastric tube, during insertion, perforating the upper and lower segments of atretic esophagus (type C) and ending up in the stomach. Symptoms and imaging of the newborn are presented and the causative factors of the incident discussed.

Physician staffing needs in critical care departments. / Estimación de las necesidades de profesionales médicos en los servicios de medicina intensiva.

Departments of Critical Care Medicine are characterized by high medical assistance costs and great complexity. Published recommendations on determining the needs of medical staff in the DCCM are based on low levels of evidence and attribute excessive significance to the structural/welfare approach (physician-to-beds ratio), thus generating incomplete and minimalistic information. The Spanish Society of Intensive Care Medicine and Coronary Units established a Technical Committee of experts, the purpose of which was to draft recommendations regarding requirements for medical professionals in the ICU. The Technical Committee defined the following categories: 1) Patient care-related aspects; 2) Activities outside the ICU; 3) Patient safety and clinical management aspects; 4) Teaching; and 5) Research. A subcommittee was established with experts pertaining to each activity category, defining criteria for quantifying the percentage time of the intensivists dedicated to each task, and taking into account occupational category. A quantitative method was applied, the parameters of which were the number of procedures or tasks and the respective estimated indicative times for patient care-related activities within or outside the context of the DCCM, as well as for teaching and research activities. Regarding non-instrumental activities, which are more difficult to evaluate in real time, a matrix of range versus productivity was applied, defining approximate percentages according to occupational category. All activities and indicative times were tabulated, and a spreadsheet was created that modified a previously designed model in order to perform calculations according to the total sum of hours worked and the hours stipulated in the respective work contract. The competencies needed and the tasks which a Department of Critical Care Medicine professional must perform far exceed those of a purely patient care-related character, and cannot be quantified using structural criteria. The method for describing the 5 types of activity, the quantification of specific tasks, the respective times needed for each task, and the generation of a spreadsheet led to the creation of a management instrument.

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.

In vivo quantification of endotoxin-induced nitric oxide production in pigs from Na15NO3-infusion.

1. In this investigation the NO production rate is quantified in the pig during normotensive endotoxin-induced shock with increased cardiac output and during subsequent treatment with the NO synthase inhibitor N omega-monomethy-L-arginine (L-NMMA). NO production rate was derived from the plasma isotope-enrichment of 15N-labelled nitrate (15NO3-). 2. Three groups of animals (control, n = 5; endotoxin, n = 6; endotoxin + L-NMMA, n = 6) were anaesthetized and instrumented for the measurement of systemic and pulmonary haemodynamics. Each animal received a primed-continuous infusion of stable, non-radioactively labelled Na15 NO3 (bolus 30 mg, infusion rate 2.1 mg h-1). Arterial blood samples were taken 5, 10, 15, 30, 60 and 90 min later and every 90 minutes until the end of the experiment. 3. Continuous i.v. infusion of endotoxin was incrementally adjusted until mean pulmonary artery pressure (PAP) reached 50 mmHg and subsequently titrated to keep mean PAP approximately 35 mmHg. Hydroxyethylstarch was administered as required to maintain mean arterial pressure (MAP) > 60 mmHg. Six hours after the start of the endotoxin continuous i.v. L-NMMA (1 mg kg-1 h-1) was administered to the endotoxin + L-NMMA group. Haemodynamic data were measured before as well as 9 h after the start of the endotoxin. 4. After conversion of NO3- to nitro-trimethoxybenzene and gas chromatography-mass spectrometry analysis the total NO3- pool, basal NO3- production rate and the increase per unit time in NO3- production rate were calculated from the time-course of the 15NO3- plasma isotope-enrichment. A two compartment model was assumed for the NO3- kinetics, one being an active pool in which newly generated NO3- appears and from which it is eliminated, the other being an inactive volume of distribution in which only passive exchange takes place with the active compartment. 5. Although MAP did not change during endotoxin infusion alone, cardiac output (CO) increased by 42 +/- 40% (P < 0.05 versus baseline) by the end of the experiment due to a significant (P < 0.05 versus baseline) fall in systemic vascular resistance (SVR) to 65 +/- 25% of the baseline value. L-NMMA given with endotoxin did not change MAP, and both CO and SVR were maintained close to the pre-shock levels. 6. Baseline plasma NO3- concentrations were 43 +/- 13 and 40 +/- 10 mumol l-1 in the control and endotoxin animals, respectively, and did not differ at the end of the experiment (39 +/- 8 and 44 +/- 15 mumol l-1, respectively). The mean NO3- pool and basal NO3- production rate were 1155 +/- 294 mumol and 140 +/- 32 mumol h-1, respectively, without any intergroup difference. Endotoxin significantly increased NO3- production rate (23 +/- 10 mumol h-2, P < 0.05 versus control (6 +/- 7 mumol h-2) and endotoxin + L-NMMA groups). L-NMMA given with endotoxin (-1 +/- 2 mumol h-2, P < 0.05 versus control and endotoxin groups) had no effect. 7. Analysis of the time course of the 15NO3- plasma isotope enrichment during primed-continuous infusion of Na15NO3 allowed us to quantify the endotoxin-induced increase in NO3- production rate independently of total NO3- plasma concentrations. Low-dose L-NMMA blunted the increase in NO3- production rate while maintaining basal NO3- formation.

Effect of increased cardiac output on liver blood flow, oxygen exchange and metabolic rate during longterm endotoxin-induced shock in pigs.

We investigated hepatic blood flow, O2 exchange and metabolism in porcine endotoxic shock (Control, n = 8; Endotoxin, n = 10) with administration of hydroxyethylstarch to maintain arterial pressure (MAP)>60 mmHg. Before and 12, 18 and 24 h after starting continuous i.v. endotoxin we measured portal venous and hepatic arterial blood flow, intracapillary haemoglobin O2 saturation (Hb-O2%) of the liver surface and arterial, portal and hepatic venous lactate, pyruvate, glycerol and alanine concentrations. Glucose production rate was derived from the plasma isotope enrichment during infusion of [6,6-2H2]-glucose. Despite a sustained 50% increase in cardiac output endotoxin caused a progressive, significant fall in MAP. Liver blood flow significantly increased, but endotoxin affected neither hepatic O2 delivery and uptake nor mean intracapillary Hb-O2% and Hb-O2% frequency distributions. Endotoxin nearly doubled endogenous glucose production rate while hepatic lactate, alanine and glycerol uptake rates progressively decreased significantly. The lactate uptake rate even became negative (P<0.05 vs Control). Endotoxin caused portal and hepatic venous pH to fall significantly concomitant with significantly increased arterial, portal and hepatic venous lactate/pyruvate ratios. During endotoxic shock increased cardiac output achieved by colloid infusion maintained elevated liver blood flow and thereby macro- and microcirculatory O2 supply. Glucose production rate nearly doubled with complete dissociation of hepatic uptake of glucogenic precursors and glucose release. Despite well-preserved capillary oxygenation increased lactate/pyruvate ratios reflecting impaired cytosolic redox state suggested deranged liver energy balance, possibly due to the O2 requirements of gluconeogenesis.

Intrapulmonary ectopic liver.

A case of intrapulmonary ectopic liver in a patient who had undergone right-sided diaphragmatic hernia is described. The intrapulmonary ectopic liver was found incidentally in chest x-ray at the age of 6 years. The final diagnosis was established at thoracotomy. Fewer than 10 cases of intrathoracic ectopic liver have been reported previously, but an intrapulmonary ectopic liver like the present case has not been described previously.

Tracheal intubation using the mobile C-MAC video laryngoscope or direct laryngoscopy for patients with a simulated difficult airway.

BACKGROUND: Several studies have shown that video laryngoscopy enhances the laryngeal view in patients with apparently normal and anticipated difficult airways. The utility of the novel, portable, battery-powered C-MAC video laryngoscope is unproven, but its design makes it potentially useful for emergency situations. We hypothesized that, in patients with a simulated difficult airway created by means of a rigid cervical immobilization collar, the rate of glottic views considered "failed" under direct laryngoscopy could be significantly reduced with the C-MAC video laryngoscope. METHODS: Following power analysis and ethical approval, 43 adults undergoing surgery under general anesthesia were studied. First, direct laryngoscopy was performed with the naked eye with and without applying external laryngeal pressure (BURP maneuver). The best-obtained view was graded by the laryngoscopist without looking at the video monitor. A second anesthesiologist, who was blinded to the laryngeal view obtained under direct laryngoscopy, graded the laryngeal view on the video monitor. A difficult airway was then created and the laryngoscopy sequence repeated. Endotracheal intubation was then attempted under video-aided visualization. RESULTS: In patients with a normal airway, the glottic view was considered as "good" in the vast majority of patients (40-43/43; 93-100%) regardless of the laryngoscopy technique used. When a difficult airway was created, the glottic view was graded as "failed" in 30/43 (70%) and 16/43 (37%) of patients under direct laryngoscopy without and with the BURP maneuver, respectively (P=0.0047). Using video laryngoscopy, significantly fewer laryngoscopic views were graded as "failed" without (14%, P<0.0001) and with the BURP maneuver (5%, P=0.0003) compared to direct laryngoscopy. Endotracheal tube placement was successful in 88% of patients with a difficult airway. CONCLUSION: The C-MAC video laryngoscope effectively enhanced the laryngeal view in patients with limited inter-incisor distance and eliminated cervical spine clearance. However, endotracheal tube placement failed in 5/43 patients despite a mostly good laryngeal view.

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.

[Calculation of staffing requirements in anesthesia]. / Personalbedarfskalkulation in der Anästhesie.

Historically, calculation of staffing requirements for anesthesia has developed from index numbers derived from the workplace method to the service performance method (XX time). The DRG revenues result from an average calculation of costs that results from an assumed calculation of staffing requirements based on the service performance method. In contrast to the principle of full cost coverage, a much stronger process orientation is needed under the conditions of the DRG system. When calculating personnel needs this process orientation also requires that it be oriented to the organization by differentiating between theater-related and non-theater-related anesthesiological services. In a second step the services rendered in a specified organization are then assessed for efficiency and if necessary optimized. Just as it applies to the whole clinical center, in departments of anesthesiology DRG revenues should be brought in line with the actual costs.

[Influence of clonidine-induced systemic sympathicolysis on oxygenation and perfusion of the liver. Investigations with healthy pigs under general anesthesia]. / Einfluss der Clonidin-induzierten systemischen Sympathikolyse auf die Oxygenierung und Perfusion der Leber. Untersuchungen am gesunden Hausschwein in Allgemeinanästhesie.

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.

[Pharmacological peculiarities and problems with older patients]. / Pharmakologische Besonderheiten und Probleme des älteren Patienten.

Because of demographic developments, the fraction of the German population over 65 years of age in the year 2025 will have risen to 20% and will continue to rise so that in 2030 this number will have doubled compared to today's numbers. This has a huge impact on the requirements for anaesthesiologic procedures. In addition to the frequent multi-morbidity in this age group, physiologic changes also occur in the elderly which have to be taken into consideration during the entire perioperative management of these patients. Renal, cardiovascular and hepatic function are impaired in many elderly patients. A major concern in addition to cardiovascular and operative complications is the postoperative cognitive dysfunction (POCD), not only because of its implications for the patient but also because of economical consequences. Regional anaesthesia has some benefits when compared to general anaesthesia as it leads to a reduction in thromboembolic and respiratory complications.

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

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.

[Alcohol--a perioperative problem of anaesthesia and intensive care medicine]. / Alkohol als perioperatives Problem in Anästhesiologie und Intensivmedizin.

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.).

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.

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.