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A Dupeyrat

Publications and source records attributed to A Dupeyrat.

5 recordsLinked to original sources
PubMed1998

Transcutaneous CO2 tension effects of clonidine in paediatric caudal analgesia.

In adults, clonidine when added to bupivacaine, results in no detectable respiratory depressant effect except when carbon dioxide challenge is performed. However, to date no investigations have quantified this in children. Twenty-four children (nine months to seven years) were randomized in a double-blind study into two groups. After induction, a caudal block was performed with 1 ml.kg-1 0.25% bupivacaine. Clonidine 1 microgram.kg-1 was added in the clonidine group, and 1 ml normal saline in the placebo group. Patients were monitored in the recovery room for three h from arrival to discharge with continuous pulse oximetry, respiratory rate, a transcutaneous CO2 tension (tcPCO2) every 15 min, and a four point sedation score every 30 min. Mean tcPCO2 and respiratory rate values were not different between the two groups. Apnoea and desaturation less than 97% were not observed. The sedation score decreased with time in both groups, and the score time interval was significantly higher in the clonidine group (P < 0.05). All the patients left the recovery room with a sedation score of 1, excepting four in the clonidine group with a sedation score of 2. Clonidine 1 microgram.kg-1 with 0.25% bupivacaine mixture in caudal analgesia in children did not induce an increase in tcPCO2 despite prolonged sedation.

Adrenergic alpha-Agonists↗
PubMed1991

Effects of sodium-nitroprusside and urapidil on gas exchange and ventilation-perfusion relationships in patients with congestive heart failure.

Vasodilators usually decrease arterial PO2 in patients with congestive heart failure (CHF) because of alteration in ventilation-perfusion (Va/Q) relationships. The effects of sodium nitroprusside (SNP) and urapidil (U), a new selective alpha 1-receptor antagonist, were investigated in seven patients with CHF. The distribution of ventilation and perfusion was examined using the multiple gas elimination technique. The haemodynamic responses to SNP and U were similar, cardiac index increasing by 25% with SNP and by 31% with U. Despite a similar increase of mixed venous oxygen tension, the arterial PO2 decreased from 11.3 +/- 0.8 to 9.6 +/- 0.6 kPa (p less than 0.01) with SNP but remained unchanged (11.0 +/- 0.9 vs 11.4 +/- 0.8 kPa, NS) with U. SNP and U both increased perfusion to lung units with Va/Q ratios of 0.1 or less with no change in shunt fraction. The fractional perfusion to total low Va/Q ratios (low Va/Q + shunt) was higher with SNP than with U (14.1 +/- 2.6 vs 9.5 +/- 2.3%, p less than 0.01). The results suggest that gas exchange and Va/Q relationships are altered less with U than with SNP in patients with CHF.

Adrenergic alpha-Antagonists↗
PubMed1990

[Subarachnoid hematoma and spinal anesthesia].

Two cases of spinal subarachnoid haematoma occurring after spinal anaesthesia are reported. In the first case, lumbar puncture was attempted three times in a 81-year-old man; spinal anaesthesia trial was than abandoned, and the patient given a general anaesthetic. He was given prophylactic calcium heparinate soon after surgery. On the fourth day, the patient became paraparetic. Radioculography revealed a blockage between T10 and L3. Laminectomy was performed to remove the haematoma, but the patient recovered motor activity only very partially. The second case was a 67-year-old man, in whom spinal anaesthesia was easily carried out. He was also given prophylactic calcium heparinate soon after surgery. On the fourth postoperative day, pulmonary embolism was suspected. Heparin treatment was then started. Twelve hours later, lumbar and bilateral buttock pain occurred, which later spread to the neck. On the eighth day, the patient had neck stiffness and two seizures. Emergency laminectomy was carried out, which revealed a subarachnoid haematoma spreading to a level higher than T6 and below L1, with no flow of cerebrospinal fluid, and a non pulsatile spinal cord. Surgery was stopped. The patient died on the following day. Both these cases are similar to those previously reported and point out the role played by anticoagulants. Because early diagnosis of spinal cord compression is difficult, the prognosis is poor, especially in case of paraplegia.

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