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R Tenicela

Publications and source records attributed to R Tenicela.

15 recordsLinked to original sources

Paravertebral-peridural block technique: a unilateral thoracic block.

A reliable, safe approach to achieving unilateral anesthesia in multiple contiguous thoracic dermatomes would be of great benefit to anesthesiologists in the acute and chronic pain setting. The multidermatomal intercostal technique is one such approach, although the anatomical mechanism of this nerve block is a matter of debate. At our pain clinic, we have used another technique, a modification of the paravertebral block, to achieve multiple segments of unilateral sensory blockade. We have used this technique, which we call the paravertebral-peridural block, for over 20 years in the treatment of various pain problems. In retrospective analysis of the 384 blocks performed from 1982 to 1986, there was one pneumothorax (0.26%), one thecal puncture (0.26%), and two accidental intrathecal injections (0.52%). Eighteen blocks (4.6%) resulted in transient hypotension. There were no permanent sequelae. Ninety-three percent of blocks were evaluated as "good" or "excellent" in quality. Bilateral sensory blockade was documented in five patients (1.3%). In order to clarify the mechanism of bilateral blockade resulting from a unilateral technique, we injected four fresh cadavers with colored latex solution using the paravertebral-peridural approach. This revealed spread of the latex across the midline prevertebrally to the contralateral paravertebral space. We conclude that the paravertebral-peridural thoracic block is a reliable, safe technique for achieving unilateral anesthesia over multiple dermatomes with a single injection.

Analgesia, Epidural↗

Baclofen as an analgesic in chronic peripheral nerve disease.

Baclofen has shown analgesic properties in a number of animal studies but has failed as a conventional analgesic in the human postoperative dental pain model. In order to test baclofen's analgesic properties in more chronic pain conditions, we selected postherpetic neuralgia and diabetic neuropathy pain as possible trial diseases for baclofen analgesia. 15 patients with postherpetic neuralgia and 10 with diabetic neuropathy pain were treated with baclofen. In the spinal postherpetic neuralgia group and diabetic neuropathy group, there was little evidence of analgesic effect. 6 of 7 patients with facial postherpetic neuralgia had a good response to baclofen during the 3-week trial. Baclofen does not appear to be a conventional analgesic.

Adult↗

Neurohypophysial hormones in cerebrospinal fluid of adults: absence of arginine vasotocin and of a diurnal rhythm of arginine vasopressin.

We previously reported a prominent diurnal rhythm of oxytocin (OT) in human cerebrospinal fluid (CSF) similar to the brisk CSF OT rhythm in monkeys. An OT CSF rhythm has not been found in lower species. In contrast, a pronounced arginine vasopressin (AVP) rhythm has been found in lower species, but the AVP CSF rhythm is less marked in subhuman primates. In patients (n = 7) in whom lumbar drains had been temporarily placed for treatment of CSF rhinorrhea, we obtained CSF samples every 6 h. In 6 of these 7 patients, we previously reported (1) finding a prominent CSF OT rhythm, with a peak at 1200 h, by analysis of variance of repeated measures. When the samples of CSF of these same 6 patients (plus 1 additional patient) were assayed for AVP, no AVP rhythm was found. We also measured AVP, OT, and arginine vasotocin (AVT) by RIA in single samples of CSF obtained from 23 other patients. In these single samples of CSF, mean AVP was 0.9 +/- 0.11 (+/- SEM) pg/ml, and OT was 3.7 +/- 0.5 microU/ml. CSF AVT immunoreactivity was 0.6 pg/ml or less in the 23 patients. Two pools of CSF were separated by reverse phase high pressure liquid chromatography. The peak OT and AVP, as determined by RIA, coeluted exactly with synthetic and human posterior pituitary OT and AVP, respectively. No immunoreactive AVT was found in the position of synthetic AVT in the eluates. Thus, OT and AVP are present in human adult CSF, but AVT is not. The lack of a prominent rhythm of AVP in human CSF is in marked contrast to the brisk OT rhythm. The rhythm of neurohypophysial peptides in human and subhuman primates is different from the rhythm in lower species, suggesting different functions for OT and AVP in the central nervous system of various species.

Adult↗

A time-dependent peak of oxytocin exists in cerebrospinal fluid but not in plasma of humans.

Oxytocin (OT) and the oxytocin-neurophysin (OT-Np) were measured by RIA in samples of cerebrospinal fluid (CSF) obtained sequentially at 0600, 1200, 1800, and 2400 h from six patients in whom intrathecal catheters were temporarily placed for CSF rhinorrhea. The highest levels of OT in CSF were found at 1200 h. An analysis of variance of sequential measures of the concentration of OT in samples of CSF obtained every 6 h over a 30-h period showed the mean levels (+/- SEM) of OT at 1200 h, 6.41 +/- 1.13 microU/ml and 5.06 +/- 0.58 microU/ml, to be significantly higher (p less than 0.05) than mean levels of OT at 0600 h, 2.50 +/- 0.65 microU/ml; 1800 h, 2.63 +/- 0.61 microU/ml and 2.64 +/- 1.21 microU/ml; and 2400 h, 2.86 +/- 1.13 microU/ml. The levels of OT-Np in CSF did not show a similar peak. In three of the patients simultaneous samples of blood were obtained for measurement of the same peptides, but no corresponding peak of OT or its Np was found in plasma of these three patients. The level of OT in CSF at all times was also significantly higher (p less than 0.05) than the level of OT in plasma of these three patients. Levels of OT and OT-Np were measured by RIA of samples of plasma obtained hourly for a 24-h period from six healthy men and six healthy women. No diurnal variation of OT or its Np in the plasma of men or women was found. This pattern of OT in the CSF of humans is similar to the pattern of OT in the CSF of the Rhesus monkey, but in contrast to the lack of a clearly defined peak of OT in the CSF of the cat or the rat. These observations in humans reinforce the differences among species of the secretion of OT in the CSF.

Adult↗

Inadvertent abducens nerve block during therapeutic trigeminal nerve block. A case report.

A case is presented where reversible abducens nerve block accompanied second and third division trigeminal block with bupivacaine on two occasions. Intraorbital injection through the inferior orbital fissure most likely took place. Careful poistioning of the needle and limitation of the drug volume is mandatory for therapeutic trigeminal nerve blocks with neurolytic solutions.

Aged↗