Hasan Mirzai

Perioperative use of corticosteroid and bupivacaine combination in lumbar disc surgery: a randomized controlled trial.

Study Design. A prospective and controlled study of perioperative use of combined local anesthetic and corticosteroid in lumbar disc surgery. Summary of Background Data. The anti-inflammatory mechanism of corticosteroids is considered to be caused by the inhibition of phospholipase A2, which plays an important role in the pain mechanism of lumbar disc problems. Although some authors have demonstrated that the use of intramuscular bupivacaine during lumbar discectomy resulted in a marked reduction of postoperative back pain, others have reported that the key intervention was probably the administration of epidural corticosteroid. The coadministration of these two drugs in lumbar disc surgery for the relief of postoperative back pain has yet not been studied adequately. Objectives. Assessment of the combined use of perioperative corticosteroids and bupivacaine for the relief of postoperative pain after lumbar disc surgery. Methods. Forty-four selected patients had acute-onset single-level unilateral herniated nucleus pulposus that were refractory to conservative management. All patients underwent lumbar disc surgery under standard general anesthesia. Before surgical incision, the skin and subcutaneous tissues were infiltrated with 10 mL of 1% lidocaine with 1:200,000 adrenaline to produce local vasoconstriction. During wound closure, 20 mL 0.9% saline in Group 1 (n = 22) and 20 mL 0.25% bupivacaine in Group 2 (n = 22) were injected into the paravertebral muscles and subcutaneus tissues. In addition, a piece of autologous fat taken from the wound was first soaked in 40 mg of methylprednisolone for 10 minutes, then placed over the exposed nerve root, and the remaining steroid was flushed into the wound in Group 2. The wound was closed after drug administration in both groups. In the postoperative period, all patients received 100 mg of meperidine intramuscularly when needed and were allowed to receive a second dose at least 4 hours later than the first dose for postoperative analgesia. Postoperative back pain intensity, heart rate, and mean arterial pressure were assessed 1, 3, 6, and 12 hours after the conclusion of surgery. Results. Visual analog scale pain scores for the postoperative recordings were lower in Group 2 than in Group 1, but these findings were not statistically significant. Patients in Group 1 received 77.3 ± 48.8 mg meperidine, and those in Group 2 received 31.8 ± 45.5 mg meperidine, for pain medication in the first 12 hours (P < 0.05). Heart rate and mean arterial pressure were not significantly different between the two groups in all recording periods. Conclusion. It is concluded that the perioperative use of bupivacaine and corticosteroids during lumbar discectomy maintains effective postoperative analgesia and decreases opioid usage without complications.

Effect of propofol and clonidine on cerebral blood flow velocity and carbon dioxide reactivity in the middle cerebral artery.

This study was designed to evaluate the effects of propofol alone and propofol-clonidine combination on human middle cerebral artery blood flow velocity (Vmca) and cerebrovascular carbon dioxide (CO2) response by using transcranial Doppler ultrasonography. Mean Vmca in response to changes in arterial partial pressure of CO2 (Paco2) was determined under the following conditions: awake (group 1), propofol anesthesia (group 2), and combined propofol-clonidine anesthesia (group 3). Normocapnic, hypercapnic, and hypocapnic values of heart rate, mean arterial pressure, partial end-tidal CO2 pressure, Paco2, and Vmca were obtained. The mean Vmca in groups 2 and 3 was significantly lower than that in group 1 at each level of Paco2. The calculated Vmca at each level of Paco2 was not different between groups 2 and 3. There was a correlation between Paco2 and Vmca in all groups, but in the anesthetized groups the effect of Paco2 on Vmca was attenuated. The present data demonstrated that clonidine-propofol does not change CO2 reactivity compared with propofol alone, but both anesthetics attenuate cerebral blood flow compared with awake controls.

Congenital Horner's syndrome and the usefulness of the apraclonidine test in its diagnosis.

We present a seven-month-old baby with miosis of the left pupil, left hypochromia, mild ipsilateral ptosis, left hemifacial anhidrosis and asymmetrical facial flushing. A diagnosis of Horners syndrome (HS) was presumed and was confirmed by instillation of apraclonidine eye drops. Miosis was reversed upon apraclonidine instillation. Magnetic resonance imaging of the head, neck and thorax and ultrasonography of the neck and abdomen did not reveal any pathological conditions. Although delivery-related brachial plexus injury is known as the most common cause of congenital HS, it should be investigated and should include neuroimaging of the sympathetic pathway, to exclude a serious underlying disease. As in our case, a specific etiology may not always be elicited. Pharmacological testing with apraclonidine may be a practical alternative to cocaine in the diagnosis of HS.

Primary orbital neuroblastoma in a neonate.

Neuroblastoma is an undifferentiated malignant tumor of the primitive neuroblasts. Orbital neuroblastoma is typically a metastatic tumor. We describe a two-days-old girl, who presented with a large tumor in her left orbit. Magnetic resonance imaging revealed that the tumor originated from the retrobulbar area, extending into the upper and lateral orbit. She was operated on the fifth day of life. A histopathologic diagnosis of neuroblastoma was made. Medical evaluation including chest roentgenogram, ultrasonography of the abdomen, whole body computerized tomogram and bone scintigraphy showed no evidence of systemic involvement or metastasis. Neuroblastoma should be considered in the differential diagnosis of neonatal orbital tumors.

Carpal tunnel release under intravenous regional anaesthesia with ropivacaine or lidocaine

AbstractCarpal tunnel syndrome (CTS) surgery is usually performed utilizing regional anaesthesia techniques such as local infiltration, brachial plexus block and intravenous regional anaesthesia (IVRA). The present investigation aimed to compare the clinical effects of IVRA with lidocaine or ropivacaine. Forty patients undergoing carpal tunnel release were divided into two groups (20 each) and 0.1% ropivacaine or 0.25% lidocaine were administred for IVRA. All patients underwent a standard surgical procedure. The patients were asked about their satisfaction regarding analgesia. After tourniquet deflation, patients were evaluated for any signs of side effects. Verbal numerical pain scores of patients were recorded periodically in the postoperative period. Onset of and recovery from sensory anaesthesia and quantification of analgesic consumption were assessed. According to our results, 0.25% lidocaine and 0.1% ropivacaine provided satisfactory anaesthetic quality with a low toxicity profile. The recovery tim...

Functional neurosurgery in the treatment of chronic pain: A review

AbstractSurgical treatment becomes a current issue when conservative treatments are insufficient in the treatment of chronic and refractory pain. With surgical treatments, conduction of pain and its perception by the central nervous system are inhibited by neuroablative, neurostimulative methods and techniques such as provision of pain relief with the use of reservoirs and pumps. Among commonly applied neurosurgical procedures for this purpose are microvascular decompression, DREZ (dorsal root entry zone) lesioning, open or percutaneous cervical chordotomy, radiofrequency thermocoagulation, implantation of morphine reservoir and stimulator. With improvement of technical apparatus and equipment and with stereotactic and endoscopic advances the tolerability of surgical treatments has increased.

Repeated epidural injections of ketamine with preservative benzethonium chloride produce evidence for neurotoxicity in rabbits

Abstract Background and objectives: In this study, we investigated whether repeated doses of 1% ketamine with preservative benzethonium chloride, administered into the epidural space of the rabbit, caused direct neurotoxicity. Methods: Twelve rabbits were randomly assigned to two groups (ketamine and control). After the animals were anesthetized, lumbar epidural catheters were placed for repeated epidural drug delivery. The ketamine group received 1% ketamine with preservative benzethonium chloride (0.5 ml) and the control group received isotonic saline (0.5 ml) once a day for 14 consecutive days. The day after the last injection, the animals were reanaesthetized, the left and right ventricles were cannulated and perfused with 2% glutaraldehyde, 1% formaldehyde mixture, in 0.1 mol/l phosphate buffer. Then, laminectomy was performed. A five centimetre segment of the spinal cord was removed and examined by light and electron microscopy to observe possible histological changes. Microscopic examinations were ...

Neurotoxicity of chronic epidural somatostatin administration in rabbits

AbstractThe central administration of somatostatin (SMS) in humans became a subject of controversy on the issue of potential neurotoxicity on the spinal cord. The study was aimed at the assessment of the neurodegenerative effects of chronic epidural SMS administration in rabbits. Rabbits were randomly assigned to two groups: the SMS and the control group. The SMS group received 100 μg SMS and the control group received isotonic saline by epidural catheter for 15 consecutive days. Then, laminectomy was performed and the spinal cord was removed. Light and electron microscopic examinations were performed. In the control group, a mild dural inflammatory response and in the SMS group, loss of Nissl bodies at the pericarion, chromatolysis and shrinking at nucleus membranes were observed in all animals at different degrees in light microscopy. In electron microscopy, mitochondrial swellings, irregularities in both nucleus and cell membrane, splitting at myelin lamellae, degeneration at myelin sheath and shrinkin...