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T Deloof

Publications and source records attributed to T Deloof.

44 records · Page 3Linked to original sources
PubMed1980

Influence of 1% enflurane (Ethrane) anesthesia on regional cerebral blood flow repartition under normo-and hyperventilation.

This study is based on the same group of neurosurgical patients as our previous publication. All, except one, had suffered from head injury. We made a first measurement of rCBF under N2O anesthesia, a second under N2O + 1% enflurane anesthesia, both at a PaCO2 of 40 Torr. A third measurement was performed under N2O + 1% enflurane but at a PaCO2 of 30 Torr. The method we used consists of the intracarotid injection of 133Xe and recording of the radioactivity by a gammacamera. Mean arterial pressure was maintained constant by an intravenous phenylephrine drip. For each measurement of each patient, a map was drawn, representing the distribution of the regional cerebral blood flows (rCBF), compared to the mean value of the hemisphere. We have studied rCBF in one case of normal hemisphere, and in cases of traumtic lesions in acute and chronic states, taking into account that the normal brain exhibits areas with higher flow in the frontoparietal and insular regions. In the normal brain, introduction of 1% enflurane decreases uniformally mean CBF, rCBF repartition not being changed. Hyperventilation to 30 Torr shows that regions with previously higher flow react more to hypocapnia by a slightly more decreased flow. In severe brain trauma, mean CBF is generally low, and it is difficult to visualize the lesions under N2O and N2O + 1% enflurane anesthesia. Neither mean CBF, nor rCBF repartition are significantly modified. On the other hand, in the acute phase, hypocapnia causes a more decreased flow in the previously well irrigated areas, and shows a lack of vascular reactivity in the damaged region. Passing to the chronic state, the patient clinically recovering, the rCBF repartition is normalized and the contused area becomes agains vasoactive. Severe losses of neuronal tissue are characterized by definitive low flows without reactivity by hyperventilation.

Adolescent↗
PubMed1980

Effect of 1% enflurane (Ethrane) anesthesia on cerebral blood flow and metabolism in neurosurgical patients during normo- and hyperventilation.

We have measured the CBF in ten neurosurgical patients. A first measurment was made during anesthesia with nitrous oxide 70% and a second with nitrous oxide 70% + 1% enflurane, both at a PaCO2 of 40 Torr. A third measurement was performed also with nitrous oxide + 1% enflurane, but at a PaCO2 of 30 Torr. We used the method of intracarotid 133Xe injection, with a gammacamera recording. In order to avoid any decrease of cerebral perfusion pressure, which might influence the CBF, an infusion of phenylephrine was used, if needed. At a constant PaCO2 of 40 Torr, there was no statistically significant difference in CBF with nitrous oxide + 1% enflurane compared to nitrous oxide alone. No change in cerebral vascular resistance was observed. When PaCO2 was lowered to 30 Torr, under 70% nitrous oxide + 1% enflurane, there was a 43% decrease in CBF (from a mean of 42 ml/100 G/min. to a mean of 24 ml/100 g/min.). Cerebral vascular resistance had an increase of 79%. In some instances, the decrease in CBF reached values around 20 ml/100 g/min. and in one case, even less. That level is generally considered to be the lowest acceptable limit in the conscious man, though not necessarily in the anesthetised one. Under hypocapnia, the cerebral arterio-venous oxygen difference increased, but the CMRO2 did not change. There were little differences in lactate and pyruvate cerebral metabolic rates, all values remaining within normal ranges. In conclusion, we believe that enflurane is a favorable anesthetic agent for neurosurgical operations at the concentration of 1%, CMRO2 is reduced, there is no significant effect on cerebral blood vessels, CBF and CVR do not change. However, a complementary use of hypocapnia may reduce CBF to dangerously low levels, if at the start, it shows already a pathological decrease and if hyperventilation is applied at a marked degree.

Adolescent↗
PubMed1980

Effects of 1% and 2% enflurane on intracranial pressure in man.

We have studied the effects of enflurane on intracranial pressure (ICP) in 9 neurosurgical patients, whose ICP was continuously monitored for therapeutic or diagnostic purposes. The control ICP was under 15 Torr in 5 cases, under 20 Torr in 3 cases and of 25 Torr in one case. In order to achieve stable ventilatory conditions, the patients were kept under controlled ventilation, breathing a mixture of 60 to 70% nitrous oxide and oxygen. The PaCO2 was kept constant, at the pre-study level. Mean arterial pressure (MAP) was maintained stable with the administration of fluids and/or a phenylephrine drip. Cerebral perfusion pressure (CPP) was calculated as the difference between MAP and mean ICP. After a control stabilization period of about one hour, enflurane was introduced in the circuit at successive concentrations of 1 and 2% during 20 to 30 minutes. In seven patients, enflurane did not produce any change of ICP. ICP rose only in 2 patients, whose control values were of 16 and 25 Torr. The overall changes, however, are not significant. There is a small significant decrease of MAP and CPP under 2% enflurane when compared to control, of probably no clinical importance (under 10% change). Our results do not show that enflurane is entirely without effect on ICP, but we think that 1 to 2% enflurane may be used in neuroanesthesia with a reasonable margin of safety, in association with slight hyperventilation and other means or reducing ICP, in accordance to clinical requirements.

Adult↗
PubMed1980

Use of sodium nitroprusside in neurosurgical cases during anesthesia with enflurane.

In patients operated for cerebral aneurysm or angioma, the same basic method of anesthesia has been used. Premedication consisted of Thalamonal or diazepam. After induction with thiopentone, curarisation with pancuronium and tracheal intubation, anesthesia was maintained with N2O 70%, O2 30% and enflurane 1%. Small doses of fentanyl or Thalamonal were given at the beginning of anesthesia, but no more within 30 minutes before starting controlled hypotension. Adjuvant drugs and methods to reduce intracranial pressure were also used, such as dexamethasone, mannitol and cerebro-spinal fluid subtraction. The approach and dissection of the vascular lesion was done under controlled hypotension with sodium nitroprusside 0.01% solution. The mean dose of sodium nitroprusside to maintain a mean blood pressure at about 50 Torr was 1.37 mcg/kg/min.

Acid-Base Equilibrium↗
PubMed1978

The risks of tracheal intubation.

Various lesions have been described as post-intubation complications: injuries, of usually minor degree, of the pharynx and larynx, oedema of the larynx, ulcerations of the pharynx and larynx with pseudomembranes and bleeding, chondromalacy of the larynx, granulomata, oesophago-tracheal fistula, stenosis of the larynx or trachea, paralysis and synechia of the vocal cords, paralysis of the tongue. Etiologic factors of these complications are mainly chemical, in relation with the material of the tube and with the sterilization agents, or mechanical due to pressure on neighbouring tissues. Post-intubation sore throat seems independent from traumatic laryngoscopy. Although intubation is meant to provide safer ventilation, interference with respiration may occur by compression of the tube or accidental obstruction from various causes. It should not be forgotten that in anesthesia cases, for which intubation is not really required, it may be advantageous to administer the anesthetic by mask.

Aged↗
PubMedDate not supplied

Heart transplantation.

From September 1988 until March 1990, 22 orthotopic heart transplantations (HTX) were performed in 20 patients (18 male and 2 female). Median age was 56.5 years (23-66). The indication for HTX was an end-stage ischemic disease in 7 pts. a dilated cardiomyopathy in 13 pts, and a retransplantation in 2 pts. The mean waiting time was 58 days. Immunosuppressive therapy included OKT3, prednisone and azathioprine. Cyclosporine was introduced at day 10. Donor hearts were obtained from our institution in 5 cases, from other hospitals in Belgium in 9 cases, and from other European countries in 8 cases. The mean ischemic time was 129 +/- 28 min. No patient died in the operating room. During the first postoperative month, weekly endomyocardial biopsies were performed to detect early rejection. Five patients died in the early postoperative period, mainly from rejection. After a mean hospital stay of 23 days, 15 patients (75%) were discharged. During the late follow-up, 3 patients died: 1 from chronic mediasdinitis, 1 from hypoglycemia, and 1 from cardiac arrest following non-compliance with the medical treatment. In conclusion, early acute rejection after HTX still remains a major cause of death.

Adult↗
PubMedDate not supplied

A new test for phagocytosis of human alveolar macrophages in suspension, using 99mTc labelled human serum albumin particles.

Current studies on human alveolar macrophages (HAM phi) indicate that two subpopulations may exist: adherent and nonadherent HAM phi. Most works in the literature were done exclusively on adherent HAM phi. In order to obviate to the loss of nonadherent HAM phi, we elaborated a new test for measuring endocytosis in HAM phi suspensions. According to this method, HAM phi in suspension were allowed to phagocytize millimicrospheres of human serum albumin labelled with 99m Tc (0.2 less than 0 less than 0.5 m; TcK9R - Cis Sorin Biomedica). Bound activity was separated from free activity by centrifugation on PercollR. The resulting internatant ring was found to contain activity bound to HAM phi which had phagocytized human serum albumin millimicrospheres. HAM phi were characterized by morphology and cytochemistry. The method here presented allows the functional study of both adherent and non-adherent HAM phi populations.

Humans↗