Clinical Value and Operational Risks of MRI in ICU patients - A Retrospective Analysis Performed at a University Medical Center.

PURPOSE: Intensive care unit (ICU) patients have a high risk of developing complications when leaving the ICU for diagnostic procedures or therapeutic interventions. Our study examined the frequency of adverse events associated with magnetic resonance imaging (MRI) of intensive care patients and the extent of changes in therapy due to the MRI scan to weigh the risks associated with the scan against the potential benefits of an MR scan, using a change in therapy as an indicator of benefit. MATERIALS AND METHODS: 4434 ICU patients (January to December 2015) were identified by Hospital Information System (SAP-R/3 IS-H, Walldorf, Germany), ICU patient data management system Metavision (iMDsoft, Israel), and Radiology Information System (Nexus.medRIS, Version 8.42, Nexus, Germany). All intensive care and medical records (HIS) and MRI reports (RIS) were matched and further evaluated in a retrospective case-to-case analysis for biometric data, mechanical ventilation, ICU requirements, planned postoperative vs. emergency diagnostic requirements, complications and impact on further diagnosis or therapy. RESULTS: Out of 4434 ICU patients, 322 ICU patients (7.3 %) underwent a total of 385 MRI examinations. 167 patients needed a total of 215 emergency scans, while 155 patients underwent 170 planned postoperative MRI exams. 158 (94.6 %) out of 167 emergency scan patients were ventilated under continuous intravenous medication and monitoring. In the planned postoperative group, only 6 (3.9 %) out of 155 were ventilated, but a total of 38 (24.5 %) were under continuous medication. 111 patients were accompanied by nurses only during MRI. Only one severe adverse event (0.3 %) was noted and was attributed to study preparation (n = 385). In 8 MRI examinations (2.1 %), the examination was interrupted or cancelled due to the patients' condition. While all MRI examinations in the planned group were completed (n = 170, 100 %) (e. g., postoperative controls), only 207 out of 215 (96.3 %) could be performed for emergency diagnostic reasons. MRI influenced the clinical course with a change in diagnosis or therapy in 74 (19.2 %) of all 385 MRI examinations performed, and in the emergency diagnostic group it was 31.2 % (n = 67/215). CONCLUSION: Nearly 20 % of MRI examinations of ICU patients resulted in a change of therapy. With only one potentially life-threatening adverse event (0.3 %) during transport and the MRI examination, the risk seems to be outweighed by the diagnostic benefit. KEY POINTS: · The risk of adverse events associated with MRI scans in ICU patients is low.. · The rate of premature termination of ICU patients' MRI scans is low.. · Almost 20 % of ICU patients' MRI scans lead to a change of therapy..

Effects of Individualised High Positive End-Expiratory Pressure and Crystalloid Administration on Postoperative Pulmonary Function in Patients Undergoing Robotic-Assisted Radical Prostatectomy: A Prospective Randomised Single-Blinded Pilot Study.

OBJECTIVES: Robotic-assisted laparoscopic prostatectomy (RALP) is typically conducted in steep Trendelenburg position (STP). The aim of the study was to evaluate whether crystalloid administration and individual management of positive end-expiratory pressure (PEEP) improve peri- and post-operative pulmonary function in patients undergoing RALP. DESIGN: Prospective randomised single-centre single-blinded explorative study. SETTING: Patients were either allocated to a standard PEEP (5 cmH2O) group or an individualised high PEEP group. Furthermore, each group was divided into a liberal and a restrictive crystalloid group (8 vs. 4 mL/kg/h predicted body weight). Individualised PEEP levels were determined by means of preoperative recruitment manoeuvre and PEEP titration in STP. PARTICIPANTS: Informed consent was obtained from 98 patients scheduled for elective RALP. INTERVENTIONS: The following intraoperative parameters were analysed in each of the four study groups: ventilation setting (peak inspiratory pressure [PIP], plateau pressure, driving pressure [Pdriv], lung compliance [LC] and mechanical power [MP]) and postoperative pulmonary function (bed-side spirometry). The spirometric parameters Tiffeneau index (FEV1/FVC ratio) and mean forced expiratory flow (FEF25-75) were measured pre- and post-operatively. Data are shown as mean ± standard deviation (SD), and groups were compared with ANOVA. A p-value of <0.05 was considered significant. RESULTS: The two individualised high PEEP groups (mean PEEP 15.5 [±1.71 cmH2O]) showed intraoperative significantly higher PIP, plateau pressure and MP levels but significantly decreased Pdriv and increased LC. On the first and second postoperative day, patients with individualised high PEEP levels had a significantly higher mean Tiffeneau index and FEF25-75. Perioperative oxygenation and ventilation and postoperative spirometric parameters were not influenced by restrictive or liberal crystalloid infusion in either of the two respective PEEP groups. CONCLUSIONS: Individualised high PEEP levels (≥14 cmH2O) during RALP improved intraoperative blood oxygenation and resulted in more lung-protective ventilation. Furthermore, postoperative pulmonary function was improved for up to 48 h after surgery in the sum of the two individualised high PEEP groups. Restrictive crystalloid infusion during RALP seemed to have no effect on peri- and post-operative oxygenation and pulmonary function.

Randomised, controlled, open label, multicentre clinical trial to explore safety and efficacy of hyperbaric oxygen for preventing ICU admission, morbidity and mortality in adult patients with COVID-19.

INTRODUCTION: COVID-19 may cause severe pneumonitis and trigger a massive inflammatory response that requires ventilatory support. The intensive care unit (ICU)-mortality has been reported to be as high as 62%. Dexamethasone is the only of all anti-inflammatory drugs that have been tested to date that has shown a positive effect on mortality. We aim to explore if treatment with hyperbaric oxygen (HBO) is safe and effective for patients with severe COVID-19. Our hypothesis is that HBO can prevent ICU admission, morbidity and mortality by attenuating the inflammatory response. The primary objective is to evaluate if HBO reduces the number of ICU admissions compared with best practice treatment for COVID-19, main secondary objectives are to evaluate if HBO reduces the load on ICU resources, morbidity and mortality and to evaluate if HBO mitigates the inflammatory reaction in COVID-19. METHODS AND ANALYSIS: A randomised, controlled, phase II, open label, multicentre trial. 200 subjects with severe COVID-19 and at least two risk factors for mortality will be included. Baseline clinical data and blood samples will be collected before randomisation and repeated daily for 7 days, at days 14 and 30. Subjects will be randomised with a computer-based system to HBO, maximum five times during the first 7 days plus best practice treatment or only best practice treatment. The primary endpoint, ICU admission, is defined by criteria for selection for ICU. We will evaluate if HBO mitigates the inflammatory reaction in COVID-19 using molecular analyses. All parameters are recorded in an electronic case report form. An independent Data Safety Monitoring Board will review the safety parameters. ETHICS AND DISSEMINATION: The trial is approved by The National Institutional Review Board in Sweden (2020-01705) and the Swedish Medical Product Agency (5.1-2020-36673). Positive, negative and any inconclusive results will be published in peer-reviewed scientific journals with open access. TRIAL REGISTRATION: NCT04327505. EudraCT number: 2020-001349-37.

Differential trends of admissions in accident and emergency departments during the COVID-19 pandemic in Germany.

BACKGROUND: Recent studies have shown a decrease of admissions to accident and emergency (A&E) departments after the local outbreaks of COVID-19. However, differential trends of admission counts, for example according to diagnosis, are less well understood. This information is crucial to inform targeted intervention. Therefore, we aimed to compare admission counts in German A&E departments before and after 12th march in 2020 with 2019 according to demographic factors and diagnosis groups. METHODS: Routine data of all admissions between 02.12.2019-30.06.2020 and 01.12.2018-30.06.2019 was available from six hospitals in five cities from north-western, eastern, south-eastern, and south-western Germany. We defined 10 diagnosis groups using ICD-10 codes: mental disorders due to use of alcohol (MDA), acute myocardial infarction (AMI), stroke or transient ischemic attack (TIA), heart failure, pneumonia, chronic obstructive pulmonary disease (COPD), cholelithiasis or cholecystitis, back pain, fractures of the forearm, and fractures of the femur. We calculated rate ratios comparing different periods in 12.03.2020-30.06.2020 with 12.03.2019-30.06.2019. RESULTS: Forty-one thousand three hundred fifty-three cases were admitted between 12.03.2020-30.06.2020 and 51,030 cases between 12.03.2019-30.06.2019. Admission counts prior to 12.03. were equal in 2020 and 2019. In the period after 12.03., the decrease of admissions in 2020 compared to 2019 was largest between 26.03. and 08.04. (- 30%, 95% CI - 33% to - 27%). When analysing the entire period 12.03.-30.06., the decrease of admissions was heterogeneous among hospitals, and larger among people aged 0-17 years compared to older age groups. In the first 8 weeks after 12.03., admission counts of all diagnoses except femur fractures and pneumonia declined. Admissions with pneumonia increased in this early period. Between 07.05. and 30.6.2020, we noted that admissions with AMI (+ 13%, 95% CI - 3% to + 32%) and cholelithiasis or cholecystitis (+ 20%, 95% CI + 1% to + 44%) were higher than in 2019. CONCLUSIONS: Our results suggest differential trends of admission counts according to age, location, and diagnosis. An initial decrease of admissions with MDA, AMI, stroke or TIA, heart failure, COPD, cholelithiasis or cholecystitis, and back pain imply delays of emergency care in Germany. Finally, our study suggests a delayed increase of admissions with AMI and cholelithiasis or cholecystitis.

Pronounced haemodynamic changes during and after robotic-assisted laparoscopic prostatectomy: a prospective observational study.

OBJECTIVES: Robotic-assisted laparoscopic prostatectomy (RALP) is typically conducted in steep Trendelenburg position (STP). This study investigated the influence of permanent 45° STP and capnoperitoneum on haemodynamic parameters during and after RALP. DESIGN: Prospective observational study. SETTING: Haemodynamic changes were recorded with transpulmonary thermodilution and pulse contour analysis in men undergoing RALP under standardised anaesthesia. PARTICIPANTS: Informed consent was obtained from 51 patients scheduled for elective RALP in a University Medical Centre in Germany. INTERVENTIONS: Heart rate, mean arterial pressure, central venous pressure (CVP), Cardiac Index (CI), systemic vascular resistance (SVR), Global End-Diastolic Volume Index (GEDI), global ejection fraction (GEF), Cardiac Power Index (CPI) and stroke volume variation (SVV) were recorded at six time points: 20 min after induction of anaesthesia (T1), after insufflation of capnoperitoneum in supine position (T2), after 30 min in STP (T3), when controlling Santorini's plexus in STP (T4), before awakening in supine position (T5) and after 45 min in the recovery room (T6). Adverse cardiac events were registered intraoperatively and postoperatively. RESULTS: All haemodynamic parameters were significantly changed by capnoperitoneum and STP during RALP and partly normalised at T6. CI, GEF and CPI were highest at T6 (CI: 3.9 vs 2.2 L/min/m²; GEF: 26 vs 22%; CPI: 0.80 vs 0.39 W/m²; p<0.001). CVP was highest at T4 (31 vs 7 mm Hg, p<0.001) and GEDI at T6 (819 vs 724 mL/m², p=0.005). Mean SVR initially increased (T2) but had decreased by 24% at T6 (p<0.001). SVV was highest at T5 (12 vs 9%, p<0.001). Two of the patients developed cardiac arrhythmia during RALP and one patient suffered postoperative cardiac ischaemia. CONCLUSIONS: RALP led to pronounced perioperative haemodynamic changes. The combination of increased cardiac contractility and heart rate reflects a hyperdynamic situation during and after RALP. Anaesthesiologists should be aware of unnoticed pre-existing heart failure to worsen during STP in patients undergoing RALP.

Case report: 38-year-old female patient with severe legionellosis but no source of infection.

We report about a 38-year-old female patient with an extremely severe case of legionellosis. The patient had to be treated in the intensive care unit for more than a month. Extracorporeal membrane oxygenation (ECMO) had to be established in order to save the patient's life. The patient did not belong to any risk group (i.e., age >50, smoker, immunosuppression, chronic disease, male sex). Infection control investigations carried out by the Public Health Department could not reveal concrete exposures likely to cause the infection. The serotypes in the patient material (Legionella pneumophila serotype 2-14) and in the samples taken from the showerhead in the patient's apartment (Legionella pneumophila serotype 1) were not identical. Results of the examination performed according to the German Drinking Water Ordinance (Trinkwasserverordnung, TrinkwV) carried out in 2017 in the patient's apartment, showed that the technical measures limit (Technischer Maßnahmenwert, TMW) was not exceeded. The patient has survived through the extensive use and efforts of intensive care measures. In general, a concrete exposure to Legionella is often not ascertainable, as in the case presented. This raises the question of how and whether such cases of legionellosis are preventable.

The impact of obesity on pulmonary deterioration in patients undergoing robotic-assisted laparoscopic prostatectomy.

Obesity affects respiratory and hemodynamic function in anesthetized patients. The aim of this study was to evaluate the influence of the body mass index (BMI) on pulmonary changes in a permanent 45° steep Trendelenburg position (STP) during robotic-assisted laparoscopic prostatectomy (RALP). 51 patients undergoing RALP under standardized anesthesia were included. Perioperative pulmonary function and oxygenation were measured in awake patients (T0), 20 min after the induction of anesthesia (T1), after insufflation of the abdomen in supine position (T2), after 30 min in STP (T3), when controlling Santorini's plexus in STP (T4), before awakening while supine (T5), and after 45 min in the recovery room (T6). Patient-specific and time-dependent factor on ventilation and predicted peak inspiratory pressure (PIP), driving pressure (Pdriv) and lung compliance (LC) in a linear regression model were calculated. PIP and Pdriv increased significantly after induction of capnoperitoneum (T2-4) (p < 0.0001). In univariate mixed effects models, BMI was found to be a significant predictor for PIP and Pdriv increase and LC decrease. Obese patients a BMI > 31 kg/m2 reached critical PIP values ≥ 35 cmH2O. Postoperative oxygenation represented by the PaO2/FiO2 ratio was significantly decreased compared to T0 (p < 0.0001). Obesity in combination with STP and capnoperitoneum during RALP has a profound effect on pulmonary function. Increased PIP and Pdriv and decreased LC are directly correlated with a high BMI. Changes in PIP, Pdriv and LC during RALP may be predicted in relation to patient's BMI for consideration in the preoperative setting. Trial registration number Z-2014-0387-6. Registered on 8 July 2014.

Changes in intraocular pressure and optic nerve sheath diameter in patients undergoing robotic-assisted laparoscopic prostatectomy in steep 45° Trendelenburg position.

BACKGROUND: To evaluate changes in intraocular pressure (IOP) and intracerebral pressure (ICP) reflected by the optic nerve sheath diameter (ONSD) in patients undergoing robotic-assisted laparoscopic prostatectomy (RALP) in permanent 45° steep Trendelenburg position (STP). METHODS: Fifty-one patients undergoing RALP under a standardised anaesthesia. IOP was perioperatively measured in awake patients (T0) and IOP and ONSD 20 min after induction of anaesthesia (T1), after insufflation of the abdomen in supine position (T2), after 30 min in STP (T3), when controlling Santorini's plexus in STP (T4) and before awakening while supine (T5). We investigated the influence of respiratory and circulatory parameters as well as patient-specific and time-dependent factors on IOP and ONSD. RESULTS: Average IOP values (mmHg) were T0 = 19.9, T1 = 15.9, T2 = 20.1, T3 = 30.7, T4 = 33.9 and T5 = 21.8. IOP was 14.0 ± 7.47 mmHg (mean ± SD) higher at T4 than T0 (p = 0.013). Univariate mixed effects models showed peak inspiratory pressure (PIP) and mean arterial blood pressure (MAP) to be significant predictors for IOP increase. Mean ONSD values (mm) were T1 = 5.88, T2 = 6.08, T3 = 6.07, T4 = 6.04 and T5 = 5.96. The ONSD remained permanently >6.0 mm during RALP. Patients aged <63 years showed a 0.21 mm wider ONSD on average (p = 0.017) and greater variations in diameter than older patients. CONCLUSIONS: The combination of STP and capnoperitoneum during RALP has a pronounced influence on IOP and, to a lesser degree, on ICP. IOP is directly correlated with increasing PIP and MAP. IOP doubled and the ONSD rose to values indicating increased intracranial pressure. Differences in the ONSD were age-related, showing higher output values as well as better autoregulation and compliance in STP for patients aged <63 years. Despite several ocular changes during RALP, visual function was not significantly impaired postoperatively. TRIAL REGISTRATION: Z-2014-0387-6 . Registered 8 July 2014.

The impact of bowl size, program setup, and blood hematocrit on the performance of a discontinuous autotransfusion system.

BACKGROUND: Cell salvage is an essential element in the concept of blood management. Modern devices provide different bowl sizes and sensor-directed programs to optimally adjust to varying clinical situations. STUDY DESIGN AND METHODS: In an experimental performance study, the discontinuous autotransfusion device XTRA (LivaNova/Sorin) was evaluated using fresh donor blood anticoagulated with heparin 5 U/mL and adjusted to a hematocrit of 10% or 25%, representing orthopedic or cardiac surgery. Test blood was processed with the autotransfusion device XTRA in four different bowls (55 mL, 125 mL, 175 mL, and 225 mL) and in three different program modes (a standard program, an optimized program, and an emergency program). RESULTS: Processing speed increased with bowl size and with the emergency program (range, 6.4-29.8 mL red blood cells [RBCs]/min). The RBC recovery rate exceeded 90% for all bowls and programs except the 55-mL bowl with the emergency program. Plasma elimination exceeded 95% for all bowls and programs except the 225-mL bowl with the emergency and standard programs. Maximal RBC recovery (range, 94.7%-97.6%) and plasma elimination (range, 98.7%-99.5%) were obtained with the medium-sized bowls (125 mL and 175 mL) and the optimized program. Elimination rates for potassium or plasma free hemoglobin were consistently lower than for protein or albumin and were highest for heparin. CONCLUSIONS: Increased hematocrit and RBC recovery rates are obtained with the optimized program Popt with the discontinuous autotransfusion device. The emergency program Pem speeds up the process but leads to RBC loss and reduced plasma elimination rates; therefore, it should be restricted to emergency situations. All four different sized bowls have high performance. Plasma elimination is represented best by protein or albumin elimination rates.

Evaluation of the contribution of radiological imaging to the final diagnosis in medical case reports.

PURPOSE: To evaluate the clinical value and impact of radiological imaging in published medial case reports. METHODS: We analysed 671 consecutively published case reports of a peer-reviewed medical journal for case reports. The general use of radiological imaging as well as the specific imaging modality used in each case (ultrasound, x-ray, fluoroscopy, CT, MRI) was documented, and most importantly the 'final problem solver', i.e. the diagnostic modality giving the final clue to the patient's diagnosis, was identified. RESULTS: In 511 of 671 (76.1 %) analysed case reports at least one radiological modality was used in the diagnostic cascade. In 28.6% of all cases the final diagnosis was achieved by radiological imaging. All other cases were solved by the patient's history and physical examination (15.2%), histology (12.4%), and blood analysis (9.6%). When radiology was the 'final problem solver', it was mainly CT (51.6%) and MRI (30.6%). In 52.2% of the case reports the radiological image was included in the article. CONCLUSION: In case reports published in a prominent general medical journal radiological imaging is an important key player in the diagnostic process. In many cases, it is also the diagnostic tool which ultimately leads to determining the final diagnosis. KEY POINTS: • Radiology was the most important specialty for finding the final diagnosis. • CT was the most successful problem-solving imaging modality followed by MRI. • MRI and CT had the best solution rates of more than 30%.

[Ambulatory pain therapy in penetrating rectal cancer via epidural anesthesia]. / Ambulante Schmerztherapie. Behandlung bei penetrierendem Rektum-Karzinom mittels Periduralkatheter.

Treatment of cancer pain includes invasive techniques of pain therapy if necessary. Here we report the management of a 55-year-old female patient with penetrating rectal cancer using continuous lumbal epidural anesthesia. After placement and dose-finding our patient was discharged from hospital and further treatment occurred at home.

[Implementation of a web based software for documentation and control of quality of an acute pain service]. / Die webbasierte Software im Akutschmerzdienst - Implementierung, Dokumentation und Qualitätskontrolle.

Providing an acute pain service means accumulation of a large amount of data. The alleviation of data collection, improvement of data quality and data analysis plays a pivotal role. The electronic medical record (EMR) is gaining more and more importance in this context and is continuously spreading in clinical practice. Up to now only a few commercial softwares are available that specifically fit to the needs of an acute pain service. Here we report the development and implementation of such a program (Schmerzvisite, Medlinq, Hamburg, Germany) in the acute pain service of a University Hospital.

The effects of fenoterol inhalation after acid aspiration-induced lung injury.

BACKGROUND: Acid aspiration is a serious complication that can occur during general anesthesia. Studies show that beta-agonists have beneficial effects on lung injury. Therefore, we tested the effect of the nebulized beta-agonist fenoterol on lung variables in a rodent model of acid-induced lung injury. METHODS: In a prospective, randomized, and controlled study, we evaluated the effects of fenoterol inhalation on lung oxygenation, inflammation, and pulmonary histology in a rat model of acid-induced lung injury. Sprague-Dawley rats underwent sevoflurane anesthesia with tracheotomy and carotid catheter insertion. Lung injury was induced by instillation of 0.4 mL/kg 0.1 M hydrochloric acid. The lungs were ventilated for 6 h and randomized to receive either fenoterol inhalation 10 microg or saline inhalation, both at 15 and 180 min after acid aspiration. Mean arterial blood pressures and peak airway pressures were documented, arterial blood gases were determined at 30, 90, 180, 270, and 360 min, and postmortem histology was subsequently examined. Additionally, fenoterol concentrations in bronchoalveolar lavage fluid (BALF) and plasma were determined by liquid chromatography/tandem mass spectroscopy. After 360 min tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 were determined in the BALF, and lungs were dried for determination of the wet/dry ratio. RESULTS: Inhalation treatment with 10 microg fenoterol significantly increased oxygenation after 270 and 360 min when compared with placebo. Fenoterol-treated rats showed a significant decrease in IL-6 and TNF-alpha levels and in the wet/dry weight ratio of the lungs. The histologic appearance showed significantly less interstitial edema and leukocyte infiltration in the fenoterol group. The concentration of fenoterol was 10.3 microg/L (median) in the BALF and <1 microg/L in the plasma. CONCLUSIONS: Fenoterol inhalation improved oxygenation after 270 and 360 min, attenuated the release of TNF-alpha and IL-6, and diminished the lung edema and infiltration of polymorphonuclear leukocytes.

Hydrochloric acid aspiration increases right ventricular systolic pressure in rats.

BACKGROUND AND OBJECTIVE: Pulmonary aspiration of gastric acid is a serious complication during anaesthesia and may cause aspiration pneumonitis and adult respiratory distress syndrome. The development of pulmonary hypertension may aggravate the initial course of the aspiration pneumonitis. The authors hypothesized that acid aspiration induces an acute increase in right ventricular pressure in the rat heart. Additionally, it was hypothesized as a secondary study that endothelin levels would be increased in this rat model. METHODS: Male Sprague Dawley rats, anaesthetized with sevoflurane, underwent tracheostomy, and catheters were inserted into the carotid and right ventricle. Lung injury was induced by instillation of 0.4 ml kg(-1) 0.1 mol l(-1) HCl; a control group received the same volume of 0.9% NaCl. Rats were then ventilated for 6 hours. p(a)O2, mean arterial blood pressures and right ventricular systolic pressures were documented every 30 minutes, and arterial blood gases were measured at baseline, 30, 90, 180, 270 and 360 min. Wet/dry ratio was performed and additionally endothelin-1 levels were examined before and 180 and 360 min after aspiration. RESULTS: p(a)O2 values were lower, whereas right ventricular systolic pressures were significantly higher in the HCl group. Mortality rate was 50% after HCl aspiration, whereas 100% of the rats survived NaCl aspiration. Wet/dry ratio and endothelin-1 levels showed a significant increase after 180 and 360 min of HCl aspiration. CONCLUSION: Acid aspiration induces a significant increase in right ventricular systolic pressure and endothelin levels, and causes metabolic acidosis in this animal model.

Bispectral index monitoring during cardiopulmonary resuscitation repeated twice within 8 days in the same patient: a case report.

Research on cardiac resuscitation has led to various changes in the techniques and drug administration involved in modern advanced life support. Besides improving primary cardiac survival, interest is increasingly focused on a favourable neurological outcome. However, until now there has been no on-site equipment to support the clinical observations of the cardiopulmonary resuscitation (CPR) team. Bispectral index (BIS) monitoring has been used for avoiding awareness during anaesthesia for many years. We report a case of a 68-year-old patient suffering twice from cardiac arrest due to thromboembolism within a few days. While the first cardiac resuscitation was survived without neurological consequences, the patient died after the second event. Both resuscitation events were monitored using the BIS. We discuss the course of BIS values and their possible contribution to the prediction of outcome.

[Post-operative pain therapy of a chronic pain patient]. / Pharmakotherapie--Postoperative Schmerztherapie eines chronischen Schmerzpatienten.

Post-operative pain therapy of chronic pain patients poses a challenge. Here we report the perioperative management of a 39-year-old male under chronic therapy with oxycodon, gabapentin and tolperison. Particular the pharmacointeractions regarding premedication and postoperative dose finding of opioids with intravenous PCIA are discussed.

Clonidine premedication in patients with sleep apnea syndrome: a randomized, double-blind, placebo-controlled study.

Patients with sleep apnea often present with cardiac diseases and breathing difficulties, with a high risk of postoperative respiratory depression. We conducted a randomized, double-blind, prospective study in 30 adult patients with obstructive sleep apnea, undergoing elective ear-nose-throat surgery. The patients were randomly assigned to receive placebo or clonidine (2 microg/kg oral) the night before and the next morning 2 h before surgery. Spo2, heart rate, mean arterial blood pressure, snoring, and oronasal airflow were monitored for 36 h. A standard anesthesia was used consisting of propofol and remifentanil. Anesthetic drug consumption, postoperative analgesics, and pain score were recorded. In the clonidine group, mean arterial blood pressures were significantly lower during induction, operation, and emergence from anesthesia. Both propofol dose required for induction (190 +/- 32.2 mg) and anesthesia (6.3 +/- 1.3 mg . kg(-1).h(-1)) during surgery were significantly reduced in the clonidine group compared with the placebo group (induction 218 +/- 32.4, anesthesia 7.70 +/- 1.5; P < 0.05). Piritramide consumption (7.4 +/- 5.1 versus 14.2 +/- 8.5 mg; P < 0.05) and analgesia scores were significantly reduced in the clonidine group. Apnea and desaturation index were not different between the groups, whereas the minimal postoperative oxygen saturation on the day of surgery was significantly lower in the placebo than in the clonidine group (76.7% +/- 8.0% versus 82.4% +/- 5.8%; P < 0.05). We conclude that oral clonidine premedication stabilizes hemodynamic variables during induction, maintenance, and emergence from anesthesia and reduces the amount of intraoperative anesthetics and postoperative opioids without deterioration of ventilation.

Early treatment with pentoxifylline reduces lung injury induced by acid aspiration in rats.

STUDY OBJECTIVES: To evaluate the effect of pentoxifylline treatment on gas exchange and mortality immediately after bilateral instillation of hydrochloric acid. DESIGN: Randomized, prospective, placebo-controlled trial. SETTING: Animal laboratory of a university hospital. SUBJECTS: Twenty-four, adult, male Sprague-Dawley rats. METHODS: Sevoflurane-anesthetized rats (n = 12 in each group) underwent tracheostomy and insertion of a cannula into a hind paw vein and the left carotid artery. All animals received volume-controlled mechanical ventilation (zero positive end-expiratory pressure; fraction of inspired oxygen, 0.21). Acute lung injury was induced by instillation of 0.4 mL/kg 0.1 mol/L hydrochloric acid. The animals were randomized into two groups. The pentoxifylline group (n = 12) received a bolus of 20 mg/kg IV pentoxifylline after aspiration, followed by a continuous infusion of 6 mg/kg/h. The placebo group (n = 12) received an equivalent volume of saline solution. Arterial blood samples were collected for blood gas analysis 15 min and 0 min prior to aspiration and 30, 90, 180, 270, and 360 min after aspiration. Hemodynamic parameters, temperature, and ECG were recorded simultaneously. The primary end point was 6 h after aspiration. All surviving rats were killed by IV administration of pentobarbital. To assess morphologic changes due to lung injury, all animals underwent CT in inspiratory hold at the end of the experiment. MEASUREMENTS AND RESULTS: No difference in baseline measurements was observed. In pentoxifylline-treated rats, Pao(2) was significantly increased (p < 0.05) at 30, 90, 180, 270, and 360 min. Mortality at 6 h was 17% in the pentoxifylline group vs 67% in the placebo group. Placebo-treated rats showed significant abnormalities in CT lung scans compared with the pentoxifylline group. CONCLUSIONS: Acid aspiration impairs gas exchange and induces hypotension. Pentoxifylline administration shortly after acid instillation results in significant alleviation of impaired oxygenation, stabilization of BP with higher heart rates, and improved survival after 6 h.