[Prerequisites, indications and contraindications of IV-lysis of ischemic stroke with rt-PA]. / Voraussetzungen, Indikationen und Kontraindikationen der systemischen Lysebehandlung des akuten ischämischen Insultes mit rt-PA.

BACKGROUND AND PURPOSE: To evaluate prerequisites, safety, and efficacy of i.v.-thrombolysis of ischemic stroke with rtPA in an academic medical center. METHODS: Over a period of 2 years and 10 months all patients admitted with a diagnosis of stroke were recruited. Inclusion and exclusion criteria for i.v.-thrombolysis were combined from large scale randomized controlled trials, the time window, however, could be extended up to 4 hours in subjects with a negative CT-scan. Prespecified outcome parameters were the modified Rankin Scale (mRS) and the Barthel Index (BI) at 3 months, and symptomatic hemorrhagic complications. Additionally, time parameters, such as onset-admission-time, door-Ct-time, door-needle time, and onset-needle time were recorded. RESULTS: During the reported period 103 patients underwent i.v.-thrombolysis, corresponding to 14.9% of all patients with ischemic stroke, and 47% of patients with ischemic stroke arriving in < 3 hours after symptom onset. The mean baseline NIHSS was 14, the mean mRS 13 (3-34), the mean age 70 (+/- 12) years. The following time intervals were observed: Onset-admission-time 64 min., door-CT-time 27 min., admission-needle-time 80 min., and onset-needle-time 142 min. There were 4 symptomatic intracerebral hemorrhagic transformations, including 3 parenchymal hemorrhages, 2 of them lethal, and one with almost full recovery. According to the mRS, 39% of patients had a good (mRS 0-1), 72% a good to moderate recovery (mRS 0-2). The corresponding figures for the BI were 60% BI 95-100 and 72% BI > 90. The mortality was 15%. CONCLUSION: The i.v.-thrombolysis of ischemic stroke with rt-PA demands appropriate organisation of the pre- and in-hospital phase and can be performed safely and efficaciously in daily clinical routine if inclusion and exclusion criteria as well as all safety measures during the critical phase after therapy are strictly obeyed.

Intravenous tPA for ischemic stroke team performance over time, safety, and efficacy in a single-center, 2-year experience.

BACKGROUND AND PURPOSE: Safety and efficacy concerns toward thrombolysis for ischemic stroke prevail among many neurologists because of the risks of hemorrhage and the small proportion of suitable patients. We therefore prospectively assessed feasibility, safety, efficacy, and team performance in a single center to prove whether thrombolytic treatment is practical in daily clinical routine. METHODS: Patients were prospectively recruited over a 2-year period. Major inclusion and exclusion criteria from large, randomized controlled trials were combined. Prespecified outcome parameters were the modified Rankin scale (MRS) and the Barthel Index (BI) at 3 months and symptomatic hemorrhagic complications. In addition, certain time intervals during the diagnostic process preceding thrombolysis were prospectively recorded. RESULTS: Within 2 years a total of 75 patients underwent intravenous thrombolysis, corresponding to 9.4% of all admitted patients with stroke and 14.9% of patients with ischemic stroke. Mean+/-SD age was 68+/-13 (range 34 to 90) years; median baseline National Institutes of Health Stroke Scale score was 13+/-6 (range 2 to 34). Thrombolysis was started at an average time of 144 minutes after symptom onset, and 13 patients (17.3%) were treated beyond 3 hours. Two cerebral hemorrhages (2.7%) occurred. Outcome according to the MRS was good (MRS 0 to 1) in 40%, moderate (MRS 2 to 3) in 32%, and poor (MRS 4 to 5) in 13%; the corresponding results, as measured by the BI, were 61% (BI 95 to 100, good), 16% (BI 55 to 90, moderate), and 8% (BI 0 to 50, poor). The mortality rate was 15%. Over 2 years the median door-to-CT time decreased from 30 to 22 minutes (27%), and the door-to-needle time was shortened from 96 to 73 minutes (14%). The mean number of patients treated per month increased from 2 to 4. CONCLUSIONS: Thrombolytic therapy can be performed safely and efficaciously in daily clinical routine. More than a minority of acute stroke patients might be eligible for intravenous thrombolysis. The performance of a stroke team can be improved over time, subsequently increasing the proportion of eligible patients and thereby the efficiency of the method.

Scattered brain infarct pattern on diffusion-weighted magnetic resonance imaging in patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: Infarct patterns on brain imaging contribute to the etiologic classification of ischemic stroke. However, the association of specific subtypes of infarcts and etiologic mechanisms is often weak, and acute lesions are frequently missed on initial computed tomography (CT). Diffusion-weighted imaging (DWI) is superior in visualizing acute ischemic lesions as compared to CT and conventional magnetic resonance imaging (MRI). In our prospective study, we addressed the question whether a distinct pattern of infarction on DWI is associated with infarct etiology and clinical outcome. METHODS: Sixty-two patients with clinical signs of acute ischemic stroke and negative acute CT upon admission underwent DWI within 10 days after the ictus. Neurological status was documented using the NIH stroke scale. A scattered lesion pattern was defined by at least 2 separate hyperintense DWI lesions within the territory of one of the major cerebral arteries. Ischemic lesions were defined as acute if the region was demarcated strongly hyperintense in all DW images, and if the apparent diffusion coefficient was below normal. RESULTS: In 32 patients, DWI revealed a scattered lesion pattern, while in 30 patients a single acute lesion was detected. In patients with scattered lesions, potential arterial or cardiac embolic sources were detected in 26 patients (81.3%), as compared to 5 patients (16.6%) in the group with single lesions (chi(2) test, p < 0.0001). The neurological status of patients with scattered lesions improved significantly more than among patients with single lesions (Mann-Whitney test, p < 0.0003). CONCLUSION: A scattered lesion pattern on DWI in patients with acute brain infarction and negative initial CT scan is associated with an embolic etiology and may indicate a favorable clinical outcome.

Local liberation of cytokines during liver preservation.

In order to investigate locally produced mediators during the process of organ storage in liver transplantation, we collected the liver preservation solution effluent of 15 transplanted livers and compared it with serum samples taken preoperatively from donor and recipient, as well as 60 min after reperfusion. The mean ischemia time +/- SEM was 10 h 10 min +/- 53 min. Mean concentrations in University of Wisconsin preservation solution effluent were: interleukin-(IL-)1beta 154 +/- 77 pg/ml; IL-1 receptor antagonist (IL-1 ra) 1281 +/- 309 pg/ml; IL-6 412 +/- 90 pg/ml; and for tumor necrosis factor-(TNF-)alpha 74 +/- 21 pg/ml. Cytokine levels in the donors were lower than those detected in the effluent. All measured cytokines showed higher concentrations in the effluent compared to those of the recipient prior to the operation. With respect to a comparison of donor and recipient values, no correlation is evident. Likewise, the ischemic time does not correlate with effluent values. Further development of liver preservation concepts requires information about the state of the graft before reperfusion. Data on cytokine liberation may serve as a helpful tool for the further development of preservation concepts because they enable an estimation of cell activation during preservation.

Systemic liberation of interleukin-8 in the perioperative phase of liver transplantation.

Serum levels of interleukin-8 (IL-8) were investigated in the perioperative phase of liver transplantation (LTx) in order to help determine whether this cytokine might serve as a parameter for preservation injury. In a study of 45 patients undergoing LTx, systemic IL-8 was estimated at the end of the anhepatic phase, at 30, 60, and 120 min after reperfusion of the graft, and 24 h and 7 days after LTx. A maximum mean concentration of 665 +/- 135 pg/ml was seen 60 min after LTx. The minimum was found on the 1st postoperative day (POD 1): 328 +/- 33 pg/ml. Significant changes were found between 60 min and PODs 1 and 7, as well as between 120 min and POD 1. Differences in cold ischemia time were not found to be significant. We conclude that monitoring of systemic IL-8 levels is not useful in the development of new liver preservation concepts.

Systemic liberation of interleukin-1 beta and interleukin-1 receptor antagonist in the perioperative phase of liver transplantation.

We measured systemic serum levels of interleukin-1 receptor antagonist (IL-1ra), interleukin-1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), and interleukin-6 (IL-6) during the preoperative, anhepatic, and postreperfusional phases up to the 7th postoperative day in 60 patients undergoing orthotopic liver transplantation (LTx). In contrast to IL-1 beta, IL-1ra, TNF-alpha, and IL-6 showed a significant elevation in relation to the early phase after reperfusion, while TNF-alpha displayed a high grade of scatter. In addition, IL-1ra levels were significantly elevated during the anhepatic phase. Maximum serum levels were found at 15 min after reperfusion, 120 min after reperfusion, and on the 1st postoperative day, respectively. Serum levels decreased considerably at 24 h and 7 days after reperfusion. The comparative monitoring of systemic cytokine and cytokine antagonist levels, in particular the liberation of IL-1ra and IL-6 may provide useful parameters for the development of new liver preservation theories for LTx.

Surgery for Obesity- An Update of a Randomized Trial.

BACKGROUND: A prospective, randomized trial comparing vertical banded gastroplasty (VBG) and gastric bypass (GB) was performed on 106 patients between 1987 and 1990. METHODS AND RESULTS: Failures of these two operations (manifested by failure to lose weight, late weight gain or intolerance of adequate oral intake) were treated by means of a third operation, isolated gastric bypass (IGB), in which the small gastric pouch was isolated from the gastric fundus. The latter operation was significantly better than VBG or GB and achieved a 63% success rate, i.e. body mass index (BMI) < 35 kg m(2) and less than 50% excess weight. During the year following this trial an additional 54 patients underwent IGB. When this operation was performed for morbid obesity and was the Initial procedure, 96% of the patients achieved a successful result. If IGB was performed as a revision procedure or for super obesity (BMI > 50 kg m(2)), the success rate was 63% with 100% follow-up at 40 months. Major morbidity occurred in six of the 160 patients who underwent 195 operations (the trial period and subsequent year). There were no deaths and follow-up was 98%. CONCLUSIONS: The ideal gastric operation based on this study emphasizes the following requirements: a small pouch (< 15 ml) totally separated from the stomach, a pouch not dependent on staples, placed in the dependent position to prevent stasis, constructed without foreign material and with an anastomosis which permits ingestion of solid food.

New biomaterials through surface segregation phenomenon: new quaternary ammonium compounds as antibacterial agents.

Five new trisiloxane quaternary ammonium compounds were synthesized from hydrotrisiloxane with allyl glycidyl ether to yield the epoxy function. Various amines were then reacted to yield trisiloxane amines which were further reacted to methyl substitute or oxidize the beta-carbons in order to provide thermal stability. These new compounds were employed as melt additives in a nonwoven polypropylene fiber extrusion process to produce, through surface segregation, a new biomaterial with antibacterial properties.