Preparation and preliminary evaluation of 99mTc-EC-For-MLFK.

For-Met-Leu-Phe-Lys (For-MLFK), a chemotactic peptide that binds with high affinity to granulocytes and monocytes, was labeled with 99mTc using ethylene dicysteine (EC) as the metal chelating system. EC was selected because of the rapid renal excretion of its 99mTc-complex and therefore, was expected to enhance the degree of urinary elimination of the peptide-conjugate. 99mTc-EC-For-MLFK was prepared using a preformed chelate approach. After incubation of 99mTc-EC-For-MLFK with total blood, 68.1% of the labeled peptide was associated with WBC and 86% of this cell-associated activity was bound to granulocytes. Biodistribution studies in normal mice revealed a very fast blood clearance (4.1% and 0.6% of I.D. in blood at respectively 5 and 60 min p.i.). However, elimination of the labeled peptide proceeds mainly via the hepatobiliary system (24.5% of I.D. in liver and 48.8% of I.D. in intestines at 60 min p.i.) and to a much lower degree via the kidneys (17.9% in renal system at 60 min p.i.). From these results, it is concluded that 99mTc-EC-For-MLFK is not suited to image infections, despite its high binding to granulocytes, since it leads to high, non-specific, abdominal activity.

The effect of semi-automatic external defibrillation by emergency medical technicians on survival after out-of-hospital cardiac arrest: an observational study in urban and rural areas in Belgium.

The introduction of semi-automatic external defibrillators (SAEDs) allowed emergency medical technicians (EMTs) to deliver electroshocks in cases of out-of-hospital ventricular fibrillation (VF) or ventricular tachycardia (VT), often many minutes before the arrival of the mobile intensive care unit (MICU) team. In this observational study we report on the results obtained by the EMTs from the fire departments of Gent, Aalter and Brugge. In Gent, an SAED project started in May 1991. By December 1995, the SAED's electrodes had been attached in 367 cardiac arrest patients. The first rhythm detected by the device was asystole or electromechanical dissociation (EMD) in 241 patients (66%): only 5 of these patients survived to hospital discharge (2%). In the remaining 126 VF/VT cases (34%) the survival rate was 21% (26/126). In 14 of these 26 patients the shock(s) delivered by the EMTs restored spontaneous circulation before the arrival of the MICU team, with only venous cannulation and/or intubation being performed by the MICU team. In 4 other VF patients, the shock(s) delivered by EMTs converted the VF, with the MICU team successfully taking care of VF/VT relapses or postcountershock EMD. In the remaining 8 VF/VT cases, only the MICU attempts could resuscitate the patient. The SAED project in Aalter was set up in April 1993. By December 1995, care was taken for only 21 patients. None of the 4 VF/VT patients and the 17 asystole/EMD patients survived. In Brugge, there were 240 cardiac arrest cases treated with SAED between January 1991 and December 1995. Among the 89 VF/VT cases, there were 20 survivors (22%): 8 cases survived thanks to SAED shock(s) delivered by EMTs, in 3 cases survival was due to the combination of SAED shock(s) by EMTs and extensive ALS treatment by the MICU team, and in 9 cases restoration of spontaneous circulation was only obtained after application of ALS techniques by the MICU team. This observational study seems to show a beneficial effect of the introduction of SAED in Gent and Brugge. In Aalter the number of treated cases is tool low to draw conclusions. Anyhow, the global survival rate in the three areas remains low. Therefore, more efforts are needed to strengthen the other links of the chain of survival (early access to the emergency medical services-system, early basic cardiopulmonary resuscitation and early advanced life support.