Michael T. Pawlik

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 &mgr;g/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.

Central venous catheter placement: comparison of the intravascular guidewire and the fluid column electrocardiograms

Background and objective: Placement of central venous catheters in patients is associated with several risks including endocardial lesions and dysrhythmias. Correct positioning of central venous catheters in the superior vena cava is essential for immediate use. The objective of a first study was to evaluate the signal quality of an intravascular electrocardiogram (ECG) during position control using a guidewire compared with the customary fluid column-based ECG system, and to assess its efficacy of correct placement of the central venous catheter. A second study tested if dysrhythmias can be avoided by intravascular ECG monitoring during catheter and guidewire advancement. Methods: The jugular or subclavian vein of 40 patients undergoing heart surgery or who were being treated in the intensive care unit was cannulated. Intravascular ECGs were recorded during position control, and guidewire and water column lead were compared in the same patient with regard to the quality of the ECG reading and P-wave enhancement. In another 40 patients, the guidewire was inserted only 10 cm and the central venous catheter advanced under guidewire ECG control. Correct position of all the central venous catheters was confirmed by chest radiography. Results: All central venous catheters were correctly positioned in the superior vena cava. For the same catheter position, the P-wave was significantly larger in the guidewire ECG than in the fluid column system. No changes in the quality of the ECG were detected when the guidewire was advanced or withdrawn by 1 cm relative to the catheter tip. Cardiac dysrhythmias were not seen during ECG-monitored advancement of the guidewire. Conclusions: ECG quality using a guidewire lead is superior to the water column-based system. Furthermore, it is independent from the exact position of the guidewire as related to the tip of the catheter. Using intravascular guidewire ECG during advancement can prevent induction of dysrhythmias.

Comparison of Conventional Abdominal CT with MR-Enterography in Patients with Active Crohn's Disease and Acute Abdominal Pain

RATIONALE AND OBJECTIVES Patients with known Crohns disease (CD) and an acute onset of severe abdominal pain attending an emergency room frequently undergo contrast-enhanced emergency computed tomography (CT) for complication assessment. To assess small bowel changes, an additional dedicated imaging procedure such as magnetic resonance enterography (MRE) is regularly performed. Therefore, these patients undergo two imaging procedures, although the clinical and diagnostic value of such an approach is not known. In a retrospective study, we compared the diagnostic value of a conventional abdominal CT with a dedicated small bowel MRE to assess bowel wall changes as well as typical complications in patients with advanced CD. MATERIALS AND METHODS We retrospectively evaluated 53 patients with CD having a conventional abdominal multidetector-CT (MD-CT) and MRE within 2 days. Image quality and bowel inflammation was analyzed for each bowel segment. Lymph nodes, abscesses, and fistulas were evaluated. RESULTS For small bowel and colon assessment, there was no significant difference for image quality between CT and MRE. Inflammation diagnosis was not significantly different between CT (69.4%) and MRE (71.4%). Colonic inflammation was diagnosed in 30.2% based on CT and 14.3% based on MRE. The difference for the detection of lymph nodes was significant (CT 49; MRE 27), whereas the differences between fistula (CT 25, MRE 27) or abscesses (CT and MRE 32) detection were not significant. CONCLUSIONS In patients with known advanced CD with acute abdominal pain conventional abdominal MD-CT, which is frequently performed as an emergency imaging procedure, is sufficient for bowel wall assessment. Based on our data, additional dedicated small bowel imaging such as MRE seems not to be necessary.

Magnetic resonance enterography with and without biphasic contrast agent enema compared to conventional ileocolonoscopy in patients with Crohn's disease

Background: Magnetic resonance imaging (MRI) of the bowel is a valuable diagnostic tool for assessing disease activity in patients with inflammatory bowel disease (IBD). We compared magnetic resonance enterography (MRE) with and without water enema to conventional ileocolonoscopy to evaluate the advantage of a water enema for MRI diagnostics of Crohns disease (CD). Methods: We prospectively evaluated 50 patients with known CD. MRE with enema was performed in 23 cases, whereas 27 patients received an MRE without enema. All patients underwent conventional ileocolonoscopy. We assessed the degree of inflammation in both modalities, evaluating up to seven bowel segments in each patient. We compared MRE with and without rectal enema to each other and to conventional ileocolonoscopy. Results: MRE achieved a sensitivity and specificity of 100% and 74%, respectively, for detection of inflammation in the terminal ileum with enema and a sensitivity and specificity of 72% and 87%, respectively, without enema. Considering the colon, MRE with enema had a sensitivity of 79% (specificity 96%), while the examination without enema showed a sensitivity of 38% (specificity 99%). MRE with enema proved statistically superior to MRE without enema in detecting inflammation in the terminal ileum, ascending colon, and rectum (P < 0.05). Conclusions: MRE with enema is a valuable diagnostic tool for assessing inflammation in CD patients. Water enema is well tolerated and significantly improves detection of inflammation in the terminal ileum. Water enema should therefore be included in MRE protocols for CD patients. (Inflamm Bowel Dis 2012)

Bispectral index (BIS) and suppression ratio (SR) as an early predictor of unfavourable neurological outcome after cardiac arrest

INTRODUCTION Predicting the neurological outcome after cardiopulmonary resuscitation (CPR) is extremely difficult. We tested the hypothesis whether monitoring of bispectral index (BIS) and suppression ratio (SR) could serve as an early prognostic indicator of neurological outcomes after CPR. METHODS Cerebral monitoring (BIS, SR) was started as soon as possible after initiation of CPR and was continued for up to 72h. The functional neurological outcome was measured on day 3, day 7 and again one month after CPR via a clinical examination and assessment according to the cerebral performance category score (CPC). RESULTS In total 79 patients were included. Of these, 26 patients (32.9%) survived the observation period of one month; 7 of them (8.9%) showed an unfavourable neurological outcome. These 7 patients had significantly lower median BIS values (25 [21;37] vs. 61 [51;70]) and higher SR (56 [44;64] vs. 7 [1;22]) during the first 4h after the initiation of CPR. Using BIS<40 as threshold criteria, unfavourable neurological outcome was predicted with a specificity of 89.5% and a sensitivity of 85.7%. The odds ratio for predicting an unfavourable neurological outcome was 0.921 (95% CI 0.853-0.985). The likelihood to remain in a poor neurological condition decreased by 7.9% for each additional point of BIS, on average. CONCLUSION Our results suggest that BIS and SR are helpful tools in the evaluation of the neurological outcomes of resuscitated patients. Nevertheless, therapeutic decisions have to be confirmed through further examinations due to the far-ranging consequences of false positive results.

Combination of high frequency oscillatory ventilation and interventional lung assist in severe acute respiratory distress syndrome

BACKGROUND The combination of high-frequency oscillatory ventilation (HFOV) and extracorporeal carbon dioxide removal with the interventional lung assist (iLA) in severe acute respiratory distress syndrome (ARDS) represents a novel treatment option. METHODS The study used a retrospective single-center analysis of 21 consecutive adult patients with severe ARDS, ventilated with HFOV/iLA. Efficiency, side effects, and outcome of combined treatment are presented as median (interquartile range). MEASUREMENTS AND MAIN RESULTS The following were used to determine patient characteristics: sequential organ failure assessment score, 14; simplified acute physiology score II, 41; and Murray score, 4. The duration of combined treatment was 6 days. The blood flow through the iLA was 1.9 L/min. The Pao(2)/inspired fraction of oxygen ratio increased from 61 (47-86) to 98 (67-116) within 2 hours and to 106 (70-135) mm Hg at 24 hours. Paco(2) decreased from 58 (50-76) to 37 (29-47) mm Hg at 2 hours with normalization of pH 7.28 (7.16-7.36) to 7.43 (7.33-7.49) after 2 hours associated with hemodynamic stabilization. In 6 patients, complications due to iLA treatment were observed, and in 3 patients, complications associated with HFOV were seen. Weaning from HFOV/iLA was successful in 10 patients. The 30-day mortality rate was 43%, and hospital mortality rate was 57%. CONCLUSION The combination of HFOV/iLA is an option in severe pulmonary failure if conventional ventilation fails and pumpdriven extracorporeal membrane oxygenation therapy is not available.

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 &bgr;-agonists have beneficial effects on lung injury. Therefore, we tested the effect of the nebulized &bgr;-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 &mgr;g 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)-&agr; 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 &mgr;g 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-&agr; 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 &mgr;g/L (median) in the BALF and <1 &mgr;g/L in the plasma. CONCLUSIONS: Fenoterol inhalation improved oxygenation after 270 and 360 min, attenuated the release of TNF-&agr; and IL-6, and diminished the lung edema and infiltration of polymorphonuclear leukocytes.

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.

Bosentan reduces oxidative burst in acid aspiration-induced lung injury in rats

BACKGROUND Acid aspiration induces lung injury by causing an intense inflammatory reaction. Neutrophils are attracted by various cytokines, such as TNFbeta, and release reactive oxygen species, which then cause acute lung injury. Endothelin antagonists, such as bosentan, have been found to possess anti-inflammatory properties. MATERIALS AND METHODS We performed a prospective, randomised, controlled study to evaluate the effects of bosentan in a rat model of acid-induced lung injury. Sprague-Dawley rats underwent sevoflurane anaesthesia; lung injury was then induced by instillation of 1.2mL/kg, 0.1M hydrochloric acid. The lungs were ventilated for 6h and then randomised into three groups: bosentan 30mg/kg body weight, 90mg/kg body weight or sodium chloride, each applied immediately after acid aspiration via a gastric tube. RESULTS After induction of acute lung inflammation, the production of reactive oxygen species by PMN following stimulation with FMLP increased significantly. Comparison of pre-treatment and post-treatment in the 90mg/kg bosentan treatment group did not show a significant increase of reactive oxygen species following stimulation with FMLP. A comparison of the absolute difference of the MESF demonstrated a significant difference between the control group and the group treated with 90mg/kg bosentan. CONCLUSIONS Bosentan administration at 90mg/kg body weight reduced the release of reactive oxygen species after 360min in acid aspiration-induced lung injury in rats.

Implementation of a web based software for documentation and control of quality of an acute pain service

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.