Omental transposition decreases ischemic brain damage examined in a new ischemia model.

PURPOSE: The aim of this study was to determine whether omental transposition at the time of focal cerebral ischemia can decrease ischemic brain damage produced in dogs, in a new ischemia model, which had been described by us. METHODS: In group 1 (n = 5), the left internal carotid artery and arterial circle of the brain (posterior communicating artery in humans) were occluded permanently. In group 2 (n = 5), additionally to this ischemia model, omental transposition was performed simultaneously. In the postoperative early period (first 24 h), single photon emission computed tomography (SPECT) and in the late period (72-96 h) SPECT and magnetic resonance imaging (MRI) of the brain were performed. Mann-Whitney U, paired t and Wilcoxon signed rank tests were used for statistical analyses, and p < 0.05 was considered significant. RESULTS: The dogs had a neurological score (NS) of 3.6 +/- 0.5 and 3.4 +/-0.5 in groups 1 and 2, respectively, in the early period (p > 0.05). In the late period, the dogs had an NS of 4.4 +/- 0.5 and 5.6 +/- 0.5 in groups 1 and 2, respectively (p < 0.05). The NS of each group differed significantly between the early and late period (p < 0.05). Early SPECT imaging showed 50 +/- 7.0% and 52 +/- 8.4% hypoperfusion corresponding to the left middle cerebral artery territory in groups 1 and 2, respectively (p > 0.05). In the late period, the degree of hypoperfusion decreased to 34 +/- 5.5% and 12 +/- 4.8% in groups 1 and 2, respectively (p < 0.05). The degree of hypoperfusion in both groups changed significantly between the early and late period (p < 0.05). In T(1)- and T(2)-weighted MRI images, the volume of the lesion in group 1 was significantly greater than in group 2 (p < 0.001). CONCLUSION: In our new ischemia model, simultaneous omental transposition is helpful in reversing the neurologic deficit and cerebral ischemic damage.

Comparison of intrathecal isobaric bupivacaine-morphine and ropivacaine-morphine for Caesarean delivery.

BACKGROUND: This study was designed to evaluate the effects of intrathecal isobaric bupivacaine 0.5% plus morphine and isobaric ropivacaine 0.5% plus morphine combinations in women undergoing Caesarean deliveries. METHOD: Twenty-five parturients received ropivacaine 15 mg and morphine 150 micro g (RM group) and twenty-five parturients received bupivacaine 15 mg and morphine 150 micro g (BM group) for spinal anaesthesia. Sensory and motor block, haemodynamics, postoperative analgesia, fetal outcomes, and side-effects were evaluated. RESULTS: Intrathecal bupivacaine-morphine and ropivacaine-morphine provided effective sensory anaesthesia and motor block. Time to reach complete motor block was shorter and time to complete recovery from motor block was longer in the BM group than the RM group (P<0.05). The time to regression of two dermatomes and time for the block to recede to the S2 dermatome were similar in both groups (P>0.05). Time to first complaint of pain and the mean total consumption of tenoxicam were similar in both groups (P>0.05). APGAR scores at 1 and 5 min were similar in the two groups, as were mean umbilical blood pH values (P>0.05). Hypotension and pruritus were the most common side-effects in both groups during the operation. CONCLUSION: Intrathecal isobaric ropivacaine 0.5% 15 mg plus morphine 150 micro g provides sufficient anaesthesia for Caesarean delivery. The ropivacaine-morphine combination resulted in shorter motor block, similar sensory and postoperative analgesia.

Effects of nimodipine on tissue lactate and malondialdehyde levels in experimental head trauma.

We studied the effects of nimodipine on brain tissue lactate and malondialdehyde (MDA) levels one hour after experimental head trauma in 25 New Zealand rabbits. Group 1 (n=5) was the sham operated group. Group 2 (n=10) received head trauma without treatment and in group 3 (n=10) nimodipine was administered for 30 minutes intravenously (2 microg/kg/min) immediately after head trauma. In groups 2 and 3, tissue samples from the non-traumatized side was named as "a" and traumatized side as "b". The lactate and malondialdehyde contents were significantly higher in groups 2a, 2b, 3a and 3b when compared with to group 1 (P<0.05). The differences between non-treated groups (2a, 2b) and nimodipine treated groups (3a, 3b) were not significant (P>0.05). The differences between the traumatized sides (2b, 3b) and non-traumatized sides (2a, 3a) were significant (P<0.05). These results demonstrated that nimodipine is ineffective in suppressing the increase of tissue lactate and malondialdehyde levels in the early period of experimental head trauma.

The effect on intraocular pressure of tracheal intubation or laryngeal mask insertion during sevoflurane anaesthesia in children without the use of muscle relaxants.

BACKGROUND: We studied the effects of sevoflurane on intraocular pressure after induction in children undergoing either tracheal tube (TT) or laryngeal mask airway (LMA) insertion without a muscle relaxant METHODS: The study included 38 children. Anaesthesia was induced (8%) and maintained (3-4%) with sevoflurane in 100% O2. No muscle relaxant was used. A TT was inserted in group I (n=20), and an LMA in group II (n=18). IOPs were measured after induction, insertion of TT or LMA and at 1, 2 and 3 min thereafter. The heart rate, mean arterial pressures were also recorded. RESULTS: Intraocular pressures increased significantly in group I after TT (P < 0.01) and remained high until after 3 min. The pressures were similar in the LMA group at all measurements. CONCLUSION: Sevoflurane does not prevent the increase in IOP after intubation without muscle relaxants. LMA does not increase IOP in children after sevoflurane induction.

Effects of nimodipine and magnesium sulfate on endogenous antioxidant levels in brain tissue after experimental head trauma.

To examine the effects of calcium antagonists nimodipine and magnesium sulfate (MgSO4) on tissue endogenous antioxidant levels, the authors studied superoxide dismutase (SOD) and glutathione peroxidase (GPx) levels in rabbit brain 1 hour after experimental head trauma. Forty New Zealand rabbits were anesthetized and randomly divided into four groups. Group 1 (n = 10) was the sham operated group. Group 2 (n = 10), the control group, received head trauma and no treatment. Group 3 (n = 10) received head trauma and intravenous (IV) 2 microgr/kg nimodipine. Group 4 (n = 10) received head trauma and IV 100 mg/kg MgSO4. Head trauma was delivered by performing a craniectomy over the right hemisphere and dropping a weight of 20 g from a height of 40 cm. In the right (traumatized) hemisphere, SOD and GPx decreased by 57.60% +/- 9.60% and 72.93% +/- 5.51% respectively from sham values. Magnesium sulfate, but not nimodipine, reduced the magnitude of decrease of SOD and GPx to 19.43% +/- 7.15% and 39.01% +/- 7.92% respectively from sham values. In the left (nontraumatized) hemisphere, MgSO4 increased SOD to 42.43% +/- 24.76% above sham values. The authors conclude that MgSO4 treatment inhibited the decrease in SOD and GPx levels in experimental brain injury.

A preliminary study on the absorption of isometamidium chloride (Samorin) in the stomach and small intestine of rat.

The levels of absorption of isometamidium chloride (Samorin) in the stomach and intestine of the rat were determined because of problems usually associated with parenteral administration of the drug. The in situ loop method and in situ recirculation technique were used to determine the absorption of the drug in the stomach and intestine respectively. 54.8% of isometamidium chloride was absorbed in the stomach in 30 minutes while 2% was absorbed in the intestine in one hour. These results warrant the comparative study of the blood and tissue concentrations of isometamidium chloride following oral and parenteral administration.