Intrapleural bupivacaine analgesia: bolus versus continuous infusion technique for postoperative pain relief in children

The aim of the present study was to evaluate the efficacy of intrapleural bupivacaine administration either by bolus or by continuous infusion methods of postoperative pain relief in children following upper abdominal surgery. The study was carried out on 30 children scheduled for upper abdominal operation and randomly divided into two equal groups. Group A received a single dose of 1.5 mg/kg of 0.25 bupivacaine, while the other group B received 0.125 mg/kg/hr of 0.25% bupivacaine infusion after initial bolus dose of 0.4 mg/kg of 0.25% bupivacaine. The results showed significant decrease in hemodynamic data under designed techniques with significant improvement of respiratory functions. Pain relief score and Prince Henry scale were significantly decreased in both groups with longer periods of postoperative analgesia in group B. Both techniques proved as convenient postoperative safe pain killers in children following upper abdominal surgical interventions. Either methods had its own advantage and disadvantages

Hepatic and renal injuries following single and repeated halothane and isoflurane anesthesia in rats [biochemical and histological study]

In order to study hepatic and renal injuries after single and repeated halothane and isoflurane anesthesia, 48 rats were used. The animals were divided into three main groups [16 animals each], each one was further subdivided into a and b subgroups [8 animals each]. Two subgroups were used as control and received no anesthesia, but only 4 l/min. Oxygen for an hour or for 5 hours [1 hour x 5 days] [a and b subgroups]. The other four subgroups were anesthetized with either halothane 1% for an hour, halothane 1% for 5 hours [1 hour x 5 days], isoflurane 1% for an hour, or isoflurane 1% for 5 hours [1 hour x 5 days], in 4 l/min. oxygen, respectively. Blood samples were taken before and after anesthesia for liver and kidney function tests. After the last anesthetic dose the animals were decapitated and liver and kidney sections were prepared and examined. It was concluded that halothane can induce liver changes that differ quantitatively and qualitatively from those associated with isoflurane. Repeated halothane administrations are needed to produce hepatic necrosis with a mononuclear cell response. Whereas, repeated isoflurane anesthesia affected significantly rats' kidney. The biochemical changes are not good indications for the extent of injury as advanced parenchymatous injury must occur before biochemical tests show significant changes

Effects of cimetidine or ranitidine on local anaesthetic toxicity induced on the central nervous system in rats

Seventy-two rats were used in this study to demonstrate the effect of histaminergic receptor blockers [H2 blockers]; namely, cimetidine or ranitidine, when administered 20 minutes prior to lidocaine on lidocaine induced central nervous system toxicity. The animals were classified into three main groups, each was further subdivided into four subgroups to study the effects of variable dosage regimens as follows: Intraperitoneal 30, 45, 60 or 75 mg/kg lidocaine alone or together with intraperitoneal cimetidine 15, 50, 100, or 200 mg/kg, respectively, or ranitidine 7.5, 25, 50 or 100 mg/kg, respectively. The results indicated that the lidocaine toxic dose was 60 mg/kg when given alone or with ranitidine while it was 45 mg/kg when lidocaine was combined with cimetidine. Again cimetidine also enhanced the convulsive effect of lidocaine and delayed its recovery period. In conclusion, ranitidine may be a safer component of premedication than cimetidine when adverse drug interactions, specially with local anesthetics, are considered

Effect of pethidine, fentanyl and calcium gluconate on blood gases in post halothane anesthesia shivering

Postoperative halothane shivering has been of particular concern to many investigators. The purpose of this study was to compare the efficacy of pethidine [25 mg i.v.], fentanyl [25 mug i.v.] and calcium gluconate [200 mg i.v.] in reducing post-anesthesia shivering and to compare blood gases during and after suppression of visible shivering. It can be concluded that postoperative shivering after halothane anesthesia produced metabolic acidosis and hypoxemia. Pethidine, fentanyl and calcium gluconate can suppress shivering and metabolic acidosis, only calcium gluconate can suppress hypoxemia. Early treatment of postoperative halothane shivering with any of studied drugs is recommended, together with the choice of calcium gluconate, particularly in patients in whom it is better to avoid any respiratory depression

Effect of added analgesic clonidine or vasoconstrictor epinephrine to bupivacaine spinal anesthesia [experimental study on dogs]

In an attempt to study the effect of either clonidine or epinephrine on the duration of bupivacaine spinal anesthesia, 18 dogs were studied, they were divided into three equal groups, each of six dogs. In group 1, 1 ml bupivacaine [5 mg/ml] alone was injected intrathecally, whereas in group 2, clonidine [150 mug] was added to bupivacaine and in group 3 epinephrine in a dose of 200 mug was added to bupivacaine. It was found that clonidine as an adjunct to bupivacaine spinal anesthesia may provide advantage over epinephrine including prolongation of the duration of both motor and sensory blockade with more effect on the duration of sensory blockade

comparative study of local neurotoxicity of lidocaine and bupivacaine with and without epinephrine [a light and electron microscopic study]

The neurotoxicity of lidocaine [20 mg/ml] and bupivacaine [5 mg/ml] with and without epinephrine [5 mug/ml] was studied after the injection of these local anesthetic solutions extrafascicularly in the sciatic nerves of 22 rats. Light and electron microscopic examination of the nerve sections revealed altered perineural permeability with endoneural edema, axonal degeneration and Schwann cells injury. These changes were more severe when bupivacaine was injected extrafascicularly and the addition of epinephrine to lidocaine or bupivacaine aggravated the nerve damage

Comparative study between captopril nifedipine preoperatively in the hypothensive effect of halothane in dogs

This study was done on 24 dogs. They were divided into three groups each of eight animals. Anesthesia was induced with halothane in group I for two hours. Captopril was given 30 minutes before the start of anesthesia in group II and nifedipine was given one hour before anesthesia in group III. The drugs were given orally. Anesthesia was induced and maintained with halothane for two hours in both groups [II and III]. Blood samples were obtained before and after anesthesia in group I, and before and after captopril and after halothane in group II. In group III, blood samples were taken prior and after nifedipine and after halothane for Kidney function tests. Blood pressure, heart rate and ECG changes were recorded. This study showed that the administration of captopril or nifedipine potentiated the hypotensive effect of halothane when given preoperatively. Nifedipine is preferable as regards its safe effect on kidney functions and on the rapid recovery of blood pressure to normal after stoppage of halothane