[Catheter-related thrombosis during intravascular temperature management]. / Katheterthrombose während intravaskulärem Temperaturmanagement.

We report on a case of catheter-related thrombosis after 7­day catheter placement during intravascular temperature management (IVTM), in spite of the use of prophylactic anticoagulants. There were no clinical sequelae. According to the literature, occult thrombosis during ITVM could be more frequent than previously reported and dedicated monitoring for potential thrombosis may be indicated. However, a study comparing IVTM with surface cooling found no differences in clinical outcome. Therefore, n either of the methods can be recommended over the other. Further studies should evaluate the rate of occult thrombosis during the use of both cooling methods.

Detection of intracranial circulatory arrest in brain death using cranial CT-angiography.

BACKGROUND AND PURPOSE: Computed tomographic-angiography (CT-A) is becoming more accepted in detecting intracranial circulatory arrest in brain death (BD). An international consensus about the use and the parameters of this technique is currently not established. We examined intracranial contrast enhancement in CT-A after clinically confirmed BD, compared the results with electroencephalography (EEG) and Transcranial Doppler Ultrasonography (TCD) findings and developed a commonly applicable CT-A protocol. METHODS: Prospective, monocentric study between April 2008 and October 2011. EEG, TCD and CT-A were performed in 63 patients aged between 18 and 88 years (mean, 55 years) who fulfilled clinical criteria of BD. Evaluation of opacification of cerebral vascular territories in CT-A was performed in arterial as well as in venous scanning series by a neuroradiologist and a neurointensivist/neurosurgeon together. RESULTS: CT-A demonstrated a 95% sensitivity in detecting intracranial circulatory arrest when analysing arterial scanning series. We never observed venous blood return in internal cerebral veins. In three cases, BD confirmation by EEG failed because of artefacts. Confirmation of BD by TCD failed in two cases because of absent temporal window. In three cases, TCD demonstrated residual blood flow. CONCLUSION: CT-A is easily accessible in almost every hospital, offers a high spatio-temporal resolution, is operator independent and inexpensive. The results of CT-A are comparable to other established brain perfusion techniques in BD. An international consensus should be established to ascertain consistent parameters similar to fixed guidelines for other ancillary procedures to determine BD in order to prevent different scanning and evaluation protocols for detecting intracranial circulatory arrest.

Intraoperative tramadol reduces shivering but not pain after remifentanil-isoflurane general anaesthesia. A placebo-controlled, double-blind trial.

BACKGROUND AND OBJECTIVE: Postoperative shivering and pain are frequent problems in patients recovering from anaesthesia with particularly high incidences being observed after remifentanil-isoflurane-based general anaesthesia. The opioid tramadol is generally effective in preventing shivering and treating pain, but its effects are not characterized after remifentanil-based general anaesthesia. This randomized, placebo-controlled, double-blind study evaluated the effects of intraoperative intravenous tramadol on postoperative shivering and pain after remifentanil-based general anaesthesia. METHODS: After Ethics Committee approval, 60 patients scheduled for lumbar disc surgery were included. Surgery was performed under general anaesthesia (remifentanil, isoflurane). Patients were randomly assigned to receive 2 mg kg(-1) tramadol in 30 mL 0.9% saline infused intravenously (n = 30) or 30 mL saline (n = 30) 45-30 min before skin closure. The following parameters were assessed every 10 min for 2 h: shivering, pain, postoperative nausea and vomiting, sedation, heart rate, non-invasive blood pressure and peripheral oxygen saturation. The primary outcome variable was the incidence of shivering during the first 2 postoperative hours. Secondary variables were: shivering intensity, pain, postoperative nausea and vomiting, sedation, heart rate, non-invasive blood pressure and peripheral oxygen saturation. RESULTS: Shivering was less frequent in patients treated with tramadol (20% vs. 70%, P = 0.0009) and was of lower intensity (severe shivering: 10% vs. 46.7%, P = 0.003). Pain scores were similar between the groups and all other secondary outcome variables failed to reveal significant differences. CONCLUSIONS: Compared with placebo, intraoperative intravenous administration of 2 mg kg(-1) tramadol reduces the incidence and extent of postoperative shivering without alterations in pain perception after lumbar disc surgery under remifentanil-isoflurane-based general anaesthesia.

How long should patients refrain from oral food and fluid intake after general anaesthesia? An assessment of the swallowing reflex of postoperative neurosurgical patients.

OBJECTIVE: Our aim was to detect swallowing abnormalities in patients after short-term neurosurgical interventions under general anaesthesia, comparing patients with supratentorial operations with a group undergoing extracranial neurosurgery (nucleotomy). METHODS: 20 patients in each group were examined by fiberoptic endoscopic evaluation of swallowing (FEES) after general anaesthesia. RESULTS: No patient demonstrated dysphagia, aspiration, or oxygen desaturation. CONCLUSION: In these patient groups, early postoperative feeding was safe. Postoperative food intake can probably be allowed early after general anaesthesia.

Effects of propofol on H-reflex in humans.

BACKGROUND: Depression of spinal cord motoneuron excitability has been proposed to contribute to surgical immobility. The H-reflex, which measures alpha-motoneuron excitability, is depressed by volatile anesthetics, whereas the action of propofol is unknown. The objective of this study was to determine the effects of propofol anesthesia on the H-reflex. METHODS: In 13 patients (group 1), H-reflex was measured before (T0), 3 min after (T1), and 10 min after (T2) a 2-mg/kg bolus dose of propofol, followed by an infusion of 10 mg x kg(-1) x h(-1). Ten patients (group 2) were studied when propofol was given via a programmable pump set to a propofol blood concentration of 6 microg/ml, and 10 patients (group 3) were studied with the pump set to 9 microg/ml. Latencies and amplitudes of H-reflexes (H0, H1, H2) and M-responses (M0, M1, M2) of the soleus muscle were recorded, and H/M ratios (H0/M0, H1/M1, H2/M2) were calculated. RESULTS: In group 1, H-reflex amplitudes and the H/M ratio were diminished after induction with propofol (H0 vs. H1, P = 0.033; H0/M0 vs. H1/M1, P = 0.042). After 10 min of propofol infusion, the H2/M2 ratio was still decreased versus H0/M0 (P = 0.031). In group 2, no difference was detected. In group 3, propofol depressed H-reflex amplitudes at T2 (H0 vs. H2, P < 0.01), and amplitudes were also lower at T2 than at T1 (H1 vs. H2, P < 0.01). In this group, the H/M ratio decreased from T0 to T2 (H0/M0 vs. H2/M2, P < 0.002). CONCLUSIONS: During steady state conditions using propofol as the sole agent, a depression of the H-reflex is observed only at a high blood concentration of 9 microg/ml. The authors suggest that immobility during propofol anesthesia is not caused by a depression of spinal motoneuron circuit excitability.

[Routes for drug administration during cardiopulmonary resuscitation]. / Zugangswege für die Medikamentenapplikation bei Herzkreislaufstillstand.

Selecting a route for drug administration during CPR requires consideration of the speed with which access can be obtained, the technical difficulties involved in performing the procedure, the associated risk of complications, delays in drug delivery to the central circulation, and the duration of effective drug levels following injection. The peripheral venous route is the safest method, and drug delivery can be enhanced by a fluid bolus after injection of the medication. The circulation time is shortest after central venous injection, but there is some risk of complications. The femoral route is associated with a high incidence of unsuccessful catherization. The endotracheal tube provides an accessible route for administration of most drugs, but peak concentrations are lower than those obtained by other routes. While the results are almost the same as an intravenous injection, the intraosseous route is currently underrepresented in clinical practice. This method must not only be considered in pediatric patients, but in adult patients as well.

[A myoclonic seizure during propofol-alfentanil anesthesia?]. / Motorischer Krampfanfall unter Propofol-Alfentanil-Anästhesie?

Total intravenous anaesthesia with propofol and alfentanil is an established alternative to inhalation anaesthesia for intracranial neurosurgical procedures. Its usefulness has been somewhat overshadowed by reports of seizure-like movements, both during anaesthesia and in the recovery period. These can be related to the use of either anaesthetic agent, but true epileptogenic properties still remain to be demonstrated in man. Opioid-induced rigidity is a well known phenomenon and must not be mistaken for an epileptic seizure. Myoclonic motor activity can be observed even under physiological conditions, e.g. sleep. Almost all anaesthetic agents have been found to produce "epileptic" EEG changes (spikes, polyspikes, spike-wave complexes), but in man these have never been correlated to motor reactions. Propofol's pro- or anticonvulsive action is unclear. While some groups found shortened convulsing times in patients undergoing electroconvulsive therapy with propofol instead of methohexitone, others have reported activation of epileptogenic foci in the EEGs of known epileptic patients. A synergistic effect of propofol and alfentanil in the generation of seizure-like movements cannot be excluded. Whether seizure-like movements indicate a true "epileptogenic potency" of the anaesthetic drugs or are related to other phenomena remains to be studied. Electro-encephalographic monitoring during anaesthesia as well as careful observation and documentation of motor reactions may contribute to elucidation of the problem. We report a case of seizure-like movements during propofol-alfentanil anaesthesia for an elective craniotomy. A 52-year-old patient presented with a history of headaches of increasing frequency. A CT brain scan demonstrated a tumor in the left occipital region.(ABSTRACT TRUNCATED AT 250 WORDS)

[The effect of PTCA on clinical outcome in patients with coronary single vessel disease]. / Einfluss der PTCA auf den klinischen Verlauf bei Patienten mit koronarer Eingefässerkrankung.

We evaluated a 3-year clinical follow-up in 53 patients with unsuccessful PTCA, due to failure to reach the lesion (control-group) in comparison to a "matched pairs" group of 53 patients, in whom PTCA had been performed (PTCA-group). There were no deaths in the PTCA-group compared to 3 deaths (5.7%) in the control-group (ns). Two patients (3.8%) and three patients (5.7%), respectively, suffered an acute transmural myocardial infarction during the follow-up period (ns). Coronary artery bypass grafting (CABG) had been performed in five patients (9.4%) following PTCA, and in 17 patients (32.1%) of the control-group (p less than 0.002). The overall rate of serious cardiac events (death, myocardial infarction or CABG) amounted to 13.2% (seven patients) in the PTCA-group and to 43.4% (23 patients) in the control-group (p less than 0.002). Only in the PTCA-group was a repeat PTCA performed in 15 patients (28.3%) with restenosis (p less than 0.00003). 35 of 53 patients in the PTCA-group (66%) and 27 of 50 survivors in the control-group were free of symptoms at the end of follow-up (ns). These results demonstrate that PTCA in patients with single-vessel disease is followed by a marked reduction of serious cardiac events, predominantly of bypass-operations, but the necessity of a second PTCA-procedure in case of restenosis has to be considered.