Antibiotic-Impregnated Versus Silver-Bearing External Ventricular Drainage Catheters: Preliminary Results in a Randomized Controlled Trial

Background: Evaluation of antibiotic-impregnated (AI) and ionized silver particle coated external ventricular drainage catheters (EVD) in patients with subarachnoid (SAH) or intracranial hemorrhage (ICH). Methods: Between February 2011 and June 2012, 40 patients with acute hydrocephalus due to SAH, ICH or intraventricular hemorrhage were enrolled in a prospective, randomized, mono-center pilot study. Primary endpoints were defined as: number of events of cerebrospinal fluid (CSF) infections. Secondary endpoints were defined as: neurosurgical complications following the placement of the EVD, number of revisions of EVD catheters, and cost effectiveness. Results: Sixty-one EVD placements in 40 patients, 32 antibiotic-coated (Bactiseal®), 29 silver-bearing catheters (VentriGuard®), have been performed. Confirmed or high suspicion of CSF infections occurred in 11 out of 61 events (confirmed infection: p=0.71, probable infection: p=0.90). Revisions of EVD were needed in 13 cases (22%) due to CSF infection, dysfunction, impaired healing, or malplacement (p=0.37). Conclusion: Regarding CSF infection rate and dysfunction, no statistical significant differences between the two EVD catheters Bactiseal® versus VentriGuard® were found. The silver-bearing catheter might offer a safe and cost-conscious alternative to the AI cathete

Therapeutic Hypothermia Reduces Middle Cerebral Artery Flow Velocity in Patients with Severe Aneurysmal Subarachnoid Hemorrhage

Background: Transcranial Doppler (TCD) is widely used to detect and follow up cerebral vasospasm after subarachnoid hemorrhage (SAH). Therapeutic hypothermia might influence blood flow velocities assessed by TCD. The aim of the study was to evaluate the effect of hypothermia on Doppler blood flow velocity after SAH. Methods: In 20 patients treated with hypothermia (33°) due to refractory intracranial hypertension or delayed cerebral ischemia (DCI), mean flow velocity of the middle cerebral artery (MFVMCA) was assessed by TCD. Thirteen patients were treated with combined hypothermia and barbiturate coma and seven with hypothermia alone. MFVMCA was obtained within 24h before and after induction of hypothermia as well as before and after rewarming. Results: Hypothermia was induced on average 5days after SAH (range 1-12) and maintained for 144h (range 29-270). After hypothermia induction, MFVMCA decreased from 113.7±49.0 to 93.8±44.7cm/s (p=0.001). The decrease was independent of SAH-related complications and barbiturate coma. MFVMCA further decreased by 28.2cm/s between early and late hypothermia (p<0.001). This second decrease was observed in patients with DCI (p<0.001), but not in patients with intracranial hypertension (p=0.715). Compared to late hypothermia, MFVMCA remained unchanged after rewarming (65.6±32.1 vs 70.3±36.8cm/s; p=0.219). However, patients treated with hypothermia alone showed an increase in MFVMCA after rewarming (p=0.016). Conclusion: Therapeutic hypothermia after SAH decreases Doppler blood flow velocity in both intracranial hypertension and DCI cases. The results can be the effect of hypothermia-related mechanisms or resolving cerebral vasospasm during prolonged hypothermia

Evaluation of a New Brain Tissue Probe for Intracranial Pressure, Temperature and Cerebral Blood Flow Monitoring in Patients with aneurysmal subarachnoid hemorrhage

Objective: To evaluate a brain tissue probe for intracranial pressure (ICP) and temperature (TEMP) monitoring as well as determination of cerebral hemodynamics using a near infrared spectroscopy (NIRS) and indocyanine green (ICG) dye dilution method (NIRS-ICP probe). Methods: The NIRS-ICP probe was applied after aneurysmal subarachnoid hemorrhage if multimodal monitoring was established due to poor neurological condition. ICP and TEMP values were obtained from ventricular catheters and systemic temperature sensors. Repeated NIRS-ICG measurements (2 injections within 30 minutes) were performed daily for determination of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time of ICG (mttICG). Delayed cerebral ischemia was defined as brain tissue oxygen tension 35. Results: A total of 128 NIRS-ICG measurements were performed in 10 patients. The correlation coefficient between ICP and TEMP values obtained with the NIRS-ICP probe and values from routine monitoring was r=0.72 and r=0.96, respectively. The mean value was 30.3 ± 13.6 ml/100g/min for CBF, 3.3 ± 1.2 ml/100g for CBV, and 6.8 ± 1.6 sec for mttICG. The coefficient of variation from repeated NIRS-ICG measurements was 10.9% for CBF, 11.7% for CBV, and 3.8% for mttICG. The sensitivity for delayed cerebral ischemia detection was 85% and the specificity 83% using a CBFthreshold of 25 ml/100g/min. Conclusion: Multimodal monitoring using the NIRS-ICP probe is feasible with high reproducibility of measurement values and the ability to detect delayed cerebral ischemia. No safety concerns exist for the routine clinical use of the NIRS-ICP probe

Early systemic procalcitonin levels in patients with aneurysmal subarachnoid hemorrhage

Background - Early (B24 h) systemic procalcitonin (PCT) levels are predictive for unfavorable neurological outcome in patients after out-of-hospital cardiac arrest (OHCA). Subarachnoid hemorrhage (SAH) due to aneurysm rupture might lead to a cerebral perfusion stop similar to OHCA. The current study analyzed the association of early PCT levels and outcome in patients after SAH. Methods - Data from 109 consecutive patients, admitted within 24 h after SAH, were analyzed. PCT levels were measured within 24 h after ictus. Clinical severity was determined using the World Federation of Neurological Societies (WFNS) scale and dichotomized into severe (grade 4–5) and non-severe (1–3). Neurological outcome after 3 months was assessed by the Glasgow outcome scale and dichotomized into unfavorable (1–3) and favourable (4–5). The predictive value was assessed using receiver operating curve (ROC) analysis. Results - Systemic PCT levels were significantly higher in patients with severe SAH compared to those with nonsevere SAH: 0.06 ± 0.04 versus 0.11 ± 0.11 lg/l (median ± interquartile range; p < 0.01). Patients with unfavorable outcome had significantly higher PCT levels compared to those with favorable outcome 0.09 ± 0.13 versus 0.07 ± 0.15 ng/ml (p < 0.01). ROC analysis showed an area under the curve of 0.66 (p < 0.01) for PCT, which was significantly lower than that of WFNS with 0.83 (p < 0.01). Conclusions - Early PCT levels in patients with SAH might reflect the severity of the overall initial stress response. However, the predictive value is poor, especially compared to the reported predictive values in patients with OHCA. Early PCT levels might be of little use in pre- dicting neurological outcome after SAH

The impact of nonsteroidal anti-inflammatory drugs on inflammatory response after aneurysmal subarachnoid hemorrhage

Background: The degree of inflammatory response with cytokine release is associated with poor outcomes after aneurysmal subarachnoid hemorrhage (SAH). Previously, we reported on an association between systemic IL-6 levels and clinical outcome in patients with aneurysmal SAH. The intention was to assess the impact of nonsteroidal anti- inflammatory drugs (NSAIDs) and acetaminophen on the inflammatory response after SAH. Methods: Our method involved exploratory analysis of data and samples collected within a previous study. In 138 patients with SAH, systemic interleukin (IL-6) and c-reactive protein (CRP) were measured daily up to day 14 after SAH. The correlations among the cumulatively applied amount of NSAIDs, inflammatory parameters, and clinical outcome were calculated. Results An inverse correlation between cumulatively applied NSAIDs and both IL-6 and CRP levels was found (r = -0.437, p < 0.001 and r = -0.369, p < 0.001 respectively). Multivariable linear regression analysis showed a cumulative amount of NSAIDs to be independently predictive for systemic IL-6 and CRP levels. The cumulative amount of NSAIDs reduced the odds for unfavorable out- come, defined as Glasgow outcome scale 1–3. Conclusions: The results indicate a potential beneficial effect of NSAIDs in patients with SAH in terms of ameliorating inflammatory response, which might have an impact on outcome

Intensivmedizinische Behandlung von Patienten mit aneurysmatischer Subarachnoidalblutung - die Behandlung zerebraler Vasospasmen und ein Blick darüber hinaus

Nach der primären Schädigung durch die Blutung werden zerebrale Vasospasmen als die häufigste Ursache für Tod und Behinderung nach einer aneurysmatischen Subarachnoidallutung (aSAB) erachtet (Dorsch 2002, Muroi et al. 2012). Die Mortalität der mit aSAB hospitalisierten Patienten hat sich seit 1980 jährlich um 0,9 % reduziert, ohne dass gleichzeitig der Anteil von schwerbehindert Überlebenden gestiegen wäre (Lovelock et al. 2010). Dies ist nicht nur auf verbesserte Behandlungsmethoden des rupturierten Aneurysmas zurückzuführen, sondern auch auf die Fortschritte der Neurointensivmedizin (Muroi et al. 2012). Viele Patienten mit aSAB sind jünger als 55 Jahre (Johnston et al. 1998). Die sozioökonomischen Folgen von Invalidität sind schwerwiegend. Diagnostik und Therapie zerebraler Vasospasmen – mit dem Ziel, sekundäre Ischämien zu verhindern – gehören zu den Kernaufgaben der Neurointensivmedizin