Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0278134 (anesthesia)
 110,339 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dose-response curves were constructed for intrathecal morphine (M), oxymorphone (OM), hydromorphone (HM), diamorphine (DM), 14-hydroxydihydromorphine (OHM), oxycodone (OC), hydrocodone (HC) and fentanyl (F). Intrathecal catheters were placed in 69 rats under halothane/N2O anaesthesia. After recovery, baseline hot plate and tail flick latencies were measured, and a dose of opioid was given. Hot plate and tail flick latencies were assessed at 5, 15, 30, 60, 90, 120 min and then hourly until they returned to within 25% of baseline. Response latencies were converted to per cent of maximum possible effect (% MPE) and the area under the % MPE X time curve was taken as the response. This measure includes information about both potency and duration of action. Each rat received 3 opioids and saline at intervals of 2-3 days. On a fifth occasion, the animal's first treatment was repeated. Each opioid was studied over an 8-fold dose range. Results of both hot plate and tail flick were best described by a model including log(dose), a component due to development of tolerance over the 5 experimental days, and an among-rat variation term. In the hot plate test, doses equieffective in producing a response (AUC) over the dose range studied were in the order OHM less than OM less than HM less than M less than F less than DM less than HC less than OC. Slopes of the log(dose)-response curves were similar for all drugs except OHM, which had a steeper slope. A model is proposed in which hot plate and tail flick latencies are prolonged while CSF concentrations of a drug are above its minimum effective concentration, and drug is cleared from the CSF by a first-order process, possibly uptake into the spinal cord and removal via the blood. This model predicts that log(dose)-response curves will be linear, as was observed, with slopes inversely proportional to the rate constant for clearance from CSF. According to this model the steeper slope of the OHM log(dose)-response may be interpreted as indicating slower clearance from CSF. OHM has the lowest octanol/pH 7.4 buffer distribution coefficient (0.34) of all opioids studied, possibly leading to a lower rate of uptake into the spinal cord.
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PMID:Influence of polarity on dose-response relationships of intrathecal opioids in rats. 232 98

Under urethane anesthesia multiple unit activity (MUA) recordings were taken from medial and lateral preoptic and anterior hypothalamic sites in 21 rats during multiple dose intracerebroventricular (i.vt.) injections of angiotensin II (AII), using artificial CSF as control. Olfactory stimuli were also presented. Whilst lateral sites on average were significantly less responsive to AII than were medial sites, some of the former were very responsive. None of the 14 lateral sites that yielded an MUA response to AII failed to yield an MUA response to olfactory stimulation. On the other hand, 11 of 12 medial sites that yielded an MUA response to AII failed to yield an MUA response to olfactory stimulation. On the basis of these data it is suggested that the medial and lateral regions of the basal forebrain serve different functions, the former more related to internal sensing and the latter more related to integration of internal and external sensing. The findings are discussed in relation to the dual olfactory system and to theories of motivation.
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PMID:Effects of intracerebroventricular angiotensin II and olfactory stimuli on multiple unit activity in preoptic and anterior hypothalamic areas: medial-lateral comparison. 245 32

The concentrations of 3-methoxy-4-hydroxyphenylglycol (MHPG), 5-hydroxyindole-3-acetic acid (5-HIAA) and homovanillic acid (HVA) were determined in CSF of patients with hypoxia due to circulatory arrest. Patients were divided into neurologically disabled and recovered according to the Glasgow Coma Scale. CSF was collected 4, 28, 76 and 172 h after commencement of resuscitation and once from control patients subjected to spinal anaesthesia. The initial concentrations of MHPG, 5-HIAA and HVA were significantly higher in a subgroup of neurologically disabled patients who died within 76 h. In recovered patients the concentration of MHPG declined with time to the value of the control group, whereas it increased in neurologically disabled patients. In the latter group the concentration of 5-HIAA also showed an increase with time, whereas in recovered patients it declined after an initial rise. It is concluded that high concentrations of MHPG, 5-HIAA and HVA in CSF may be prognostic for hypoxic brain injury after cardiac arrest.
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PMID:Biogenic amine metabolites in human CSF after hypoxia due to cardiac arrest. 247 7

We report that hematopoietic progenitor cells expressing the CD34 antigen (CD34+ cells) transiently circulate in the peripheral blood (PB) of cancer patients treated with 7 g/m2 cyclophosphamide (HD-CTX) with or without recombinant human granulocyte macrophage-colony stimulating factor (rHuGM-CSF). In adult humans, CD34+ cells represent a minor fraction (1% to 4%) of bone marrow (BM) cells, comprising virtually all hematopoietic colony-forming progenitors in vitro and probably also stem cells capable of restoring hematopoiesis of lethally irradiated hosts. We show that CD34+ cell circulation is fivefold enhanced by rHuGM-CSF 5.5 protein micrograms/kg/day by continuous intravenous infusion for 14 days after HD-CTX. During the third week after HD-CTX (ie, when CD34+ cells peak in the circulation), large-scale collection of PB leukocytes by three to four continuous-flow leukaphereses allows the yield of 2.19 to 2.73 x 10(9) or 0.45 to 0.56 x 10(9) CD34+ cells depending on whether or not patients receive rHuGM-CSF. The number of CD34+ cells retrieved from the circulation by leukaphereses exceeds the number that can be harvested by multiple BM aspirations under general anesthesia. Thus, after therapy with HD-CTX and rHuGM-CSF, PB represents a rich source of hematopoietic progenitors possibly usable for restoring hematopoiesis after myeloablative chemoradiotherapy. To determine whether CD34+ cells found in the PB are equivalent to their marrow counterpart, we evaluated their in vitro growth characteristics and immunological phenotype by colony assays and dual-color immunofluorescence, respectively. We show that PB CD34+ cells possess qualitatively normal hematopoietic colony growth and high cloning efficiency comparable to that observed with BM CD34+ cells. In addition, PB CD34+ cells display heterogeneous surface membrane differentiation antigens analogous to BM CD34+ cells. The availability of large quantities of CD34+ cells by leukapheresis is relevant to the field of stem cell transplantation and possibly to genetic manipulations of the hematopoietic system in humans.
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PMID:Circulation of CD34+ hematopoietic stem cells in the peripheral blood of high-dose cyclophosphamide-treated patients: enhancement by intravenous recombinant human granulocyte-macrophage colony-stimulating factor. 247 16

Plasma and CSF pharmacokinetics of morphine given epidurally in combination with general anesthesia for abdominal aortic surgery were recorded. The initial plasma and CSF concentrations of morphine appeared at two minutes. The peak plasma concentrations of morphine were recorded at 8.0 +/- 2.6 minutes after epidural injection. Plasma mean residence time was 84 +/- 25.7 minutes, Vdss 121 +/- 30 L, and C1 1.5 +/- 0.32 L/min. Free morphine was not detected in plasma 360 minutes after epidural administration. The fraction of the epidural morphine that crossed the dura was 3.15% +/- 2.4 The peak CSF morphine concentrations were recorded at 56 +/- 31 minute. MRT (200 +/- 28 minute), Vdss (65 +/- 33.8 ml), and CL (0.32 +/- 0.15 ml/min) showed that variable fractions of morphine remained many hours in the CSF. Factors that could produce the interindividual variability of plasma and CSF concentrations and pharmacokinetics of epidural morphine were discussed. Abdominal aortic surgery appears to influence both plasma and CSF pharmacokinetics.
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PMID:Epidural morphine anesthesia for abdominal aortic surgery--pharmacokinetics. 248 89

Thirty six comparable patients, ASA 2, without cardiac disease, underwent aortic disobliteration, 19 under epidural 100 micrograms/kg morphine (EM) and 17 under epidural 2 micrograms/kg sufentanil (ES), combined with general anesthesia. To compare the hemodynamics, measurements were taken pre-operatively, after induction of general anesthesia, during aortic dissection, aortic cross-clamping and 3-5 minutes after the first revascularisation. Plasma and CSF drug levels were measured at intervals in 6 patients in the EM end 5 patients in the ES group. Both drugs provided satisfactory analgesia which persisted for 10.4 hours in the EM and 6.3 hours in the ES group. The fall in systemic pressure and left ventricular work in both groups after induction of general anesthesia suggests that EM and ES must be used with caution in patients with hypovolemic or cardiovascular disease. There was a significant difference in SVR between the two groups during the aortic dissection, due to a rise in SBP in the ES group and a tendency for SVR to fall in the EM group. However significant differences in left ventricular work did not occur. Notable was the absence of significant changes in filling pressure, CI and left ventricular function during aortic cross-clamping. After revascularization a significant decrease in systolic blood pressure occurred in association with an increase in heart rate in the EM group. The influence of the plasma and CSF concentrations of morphine and sufentanil on the hemodynamic changes during surgery were evaluated.
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PMID:A study of epidural morphine and sufentanil anesthesia for abdominal aortic surgery. 252 49

This study was undertaken to examine the thermal pain thresholds over a wide area of the lower body surface following the intrathecal administration of capsaicin in rats. Thermal nociceptive thresholds measured under light halothane anesthesia were determined as skin twitch or escape response latencies to the heat stimulation (52.0 degrees C) by a thermal probe. Capsaicin (50 micrograms in 10 microliters) was injected through a chronically implanted catheter whose tip was near the lumbar enlargement of the spinal cord. The hot-plate test (52.0 degrees C) was also performed in all rats tested. Increase in thermal pain thresholds were consistently observed in the low back and abdominal region, while the hind paws did not always respond with prolonged skin twitch or escape latencies. Intensities of thermal analgesia at the sole of hind paws measured by hot-plate test correlated well with those by thermal probe test. In conclusion, intrathecal capsaicin definitely produced thermal analgesia, but its intensity was considerably variable in the hind paws. These results are in keeping with our previous finding that there was much variability in the effect of capsaicin assessed by the hot-plate test, indicating a possibility that capsaicin does not spread uniformly in the CSF because of its water insolubility or difficulty in penetrating to the large nerve roots innervating the hind paws.
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PMID:[Thermal analgesia following intrathecal capsaicin administration in rats--detailed measurements of thermal analgesia over the lower body by a thermal probe]. 258 99

Forty-three ASA physical status I-II adult patients, receiving spinal anesthesia for lower abdominal or lower limb surgery, were allocated randomly to two groups. Group 1 patients (n = 21) were given heavy bupivacaine 12 mg and group 2 patients (n = 22) were given tetracaine 12 mg in 2.5 mL of 10% dextrose. Spinal anesthesia was performed in the lateral decubitus position the at L 3-4 interspace with a 25-G spinal needle. Radial artery blood samples were collected before and after spinal anesthesia fpr pH measurement using a NOVA Biomedical machine; CSF samples were collected before and after injection of local anesthetic, and local anesthetic was also collected at the same time, for pH measurement using a Radio pH meter. The time from injection to maximal cephalad spread of analgesia and level of spinal analgesia were measured by the pin-prick method. The result was regarded as a failure if pain sensation still existed at the level of the operation site after spinal anesthesia. There were 1 failure case in the bupivacaine group and 2 failures in tetracaine group. The pH of CSF and local anesthetic in these failures were compared with those in effective cases, and the results showed that there was no significant relationship between the pH value of CSF and the local anesthetic drug.
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PMID:Effects of pH of cerebrospinal fluid and local anesthetic on the success rate of spinal anesthesia. 263 18

Analgesia can be obtained during ophthalmic surgery by regional anesthesia using local anesthetic agents. As in other indications, neurological complications may occur, especially because the site of injection is close to the central nervous system. In order to evaluate the risk of retrobulbar and facial block obtained after 40 mg lidocaine and 20 mg bupivacaine injection, pharmacokinetics of both drugs was evaluated in plasma obtained from 11 patients. In addition, 3 cerebrospinal fluid samples were analyzed. Maximal plasma concentration was 0.73 +/- 0.33 micrograms.ml-1 for lidocaine and 0.19 +/- 0.06 micrograms.ml-1 for bupivacaine, obtained 24.7 +/- 23.0 min and 12.0 +/- 3.7 min after the end of injection, respectively. CSF/plasma ratio was in the range 0.05-0.26 for lidocaine and 0.56-1.33 for bupivacaine. In all patients, regional anesthesia was sufficient to perform surgery without any other analgesic drug. No sign of cardiovascular or respiratory toxicity was observed during the study.
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PMID:Pharmacokinetics of lidocaine and bupivacaine in retrobulbar and facial block. 272 18

The behaviour of Pial vessels to levels of CSF-pressure between 10 and 100 mmHg induced by vetricular infusion of mock CSF, was observed in 6 cats under barbiturate and N2O anaesthesia, using the cranial window technique and videoangiometry. Supratentorial pressure (STP) equaled infratentorial pressure in the cisterna magna (CMP) throughou. No changes in pial arterial calibres were noted up to a CMP of 13 mmHg (i.e. a cerebral perfusion pressure (CPP) of 100 mmHg). Further increase of CMP to 45 mmHg induced significant arterial dilatation of 40 +/- 3.4%. With a further rise of ventricular fluid pressure (VFP) no marked further arterial dilatation occurred. Dilatation of arteries up to 100 um resting diameter and arteries between 100 and 250 um resting diameter and arteries between 100 and 250 um was not significantly different. When CPP approached 40 mmHg, arteries were still 47 +/- 3.6% dilated. Pial venous calibre did not vary by more than 20% during elevation of VFP. At CPP 47 mmHg, small and large veins were dilated by 14%. Single venous segments were compressed by crossing pial arteries and caused upstream venous congestion and distension.
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PMID:Cerebrovascular response to elevation of ventricular pressure. 274 47


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