Biomedical subjects
F P Boersma
Publications and source records attributed to F P Boersma.
Spinal sufentanil in rats: Part I: Epidural versus intrathecal sufentanil and morphine.
Male Wistar rats were injected epidurally or intrathecally with increasing doses of sufentanil or morphine in order to determine differences in potency, onset and duration of analgesia and supra-spinal side-effects. For sufentanil, only small differences in the lowest ED50-values for analgesia and supra-spinal side-effects were observed between the two spinal routes. Given intrathecally, sufentanil had a somewhat faster onset but a shorter duration of action than did epidural sufentanil. However, intrathecal morphine when compared to epidural morphine had a faster onset with a greater potency and a longer duration of action. The stronger opioid activity of intrathecal morphine was also reflected in a reduced safety ratio for the blockade of the cornea reflex. These differences between the two opioids, with regard to their optimal route of spinal administration, are discussed in terms of lipophilicity and optimal clinical use.
Effects of adrenaline, an alpha 2-adrenoceptor agonist, the volume of injection, and the global pain state of the animal on the activity of epidural sufentanil.
A study was made of the effects of different volumes of injection product, adrenaline, the alpha 2-adrenoceptor-agonist medetomidine and Mycobacterium butyricum on epidural sufentanil in the rat. Increasing the volume of epidural sufentanil, and similarly decreasing the concentration of the injection product, resulted in a potentiation of the analgesic properties of epidural sufentanil without affecting the effects of the drug on the pinna and cornea reflexes and on muscle tonus. An analogue effect was observed if rats were tested for epidural analgesia during a chronic pain phase after inoculation with Mycobacterium butyricum. Adding adrenaline to epidural sufentanil also resulted in an increased analgesia but there was also a minor potentiation of all other behavioural parameters measured. The alpha 2-adrenoceptor-agonist medetomidine, clearly potentiated all behavioural effects induced by epidural sufentanil. As a consequence, there was no gain in specificity for epidural analgesia. Medetomidine, however, clearly reversed the normally observed skeletal muscle rigidity into a muscle hypotonia. Globally, these results thus indicate that manipulations of the volume of injection, the additional treatment with other drugs and the pain state of the animal can alter the activity of epidural sufentanil. Therefore, it might be concluded that the differences in the duration of analgesia observed with epidural sufentanil between human and animal studies can be partially explained in terms of differences between the experimental conditions.
Epidural pain treatment in the northern Netherlands. Organizational and treatment aspects.
During the past six years opiates administered in the vicinity of the medulla spinalis (intrathecally or extradurally) were shown to be successful tools in the treatment of both acute and chronic pain (1, 6). Continuous installation and long-term treatment have become possible by insertion of a permanent catheter into the epidural space. In cases where conventional analgesic therapy has remained ineffective or given rise to serious side-effects this method of analgesia should be preferred to control protracted painful conditions, most typically in cancer patients. This article presents the results of a number of cases of long-term treatment with extradural opiates and mainly focuses on outpatient treatment and the organization this requires.
Rat intubation. A method for safe and fast intubation of the rat trachea under direct vision.
A method has been developed for the safe and rapid intubation of the rat trachea under direct vision. Rats are first anaesthesized with an oxygen/nitrous oxide/halothane mixture. A modified eyelid retractor and a curved bulldog artery clamp are used to keep the animal's mouth open and the tongue to the side. A laryngoscope, fashioned from a weighing spatula and a glassfibre cable which is connected to a cold light source, is used to bring the trachea in view. The trachea is then easily intubated with a suitable intravenous canula.
Epidural sufentanil for cancer pain control in outpatients.
Fifteen patients with cancer pain refractory to other methods of pain control were treated with epidural sufentanil. They all suffered from very severe or unbearable pain but had expressed the wish to spend the last period of their lives at home. On the first day of hospitalization, an epidural catheter and a portal catheter were implanted under local anesthesia. Sufentanil was delivered by a portable infusion pump into the portal catheter. The patients remained a further 2-3 days in hospital to titrate the infusion rate to their specific needs and to monitor pain relief and possible side effects. In the home situation, the patients were supervised by their general practitioners. Nine patients had epidural sufentanil as their sole analgesic till they died; six patients needed adjunctive nonepidural medications. There were no epidural- or portal-catheter related infections or cases of respiratory depression. After 1651 patient treatment days, we have found continuous epidural sufentanil infusion to be a safe and effective method for cancer pain control in outpatients.