Lack of intraspecific biological variation between two geographical populations of Oomyzus sokolowskii (Hymenoptera: Eulophidae), a gregarious larval-pupal parasitioid of Plutella xylostella (Lepidoptera: Plutellidae)

The chalcid, Oomyzus sokolowskii Kurdjumov has been recorded in many parts of the world as a major larval-pupal, gregarious endoparasitoid of the diamondback moth, Plutella xylostella (Linnaeus), a serious pest of brassica vegetable crops worldwide. This study investigated intraspecific variation between two populations of O. sokiolowskii, one from Cape Verde Islands, West Africa and the other from Hangzhou, China. In all crosses and backcrosses between the two geographical populations, the numbers of progeny and sex ratio of progeny were similar to those obtained within each of the populations, demonstrating complete reproductive compatibility between the two populations. The two populations showed similar responses to temperature with respect to development time and survival of immature stages. Observations on the interactions between the two O. sokolowskii populations and Cotesia plutellae (Kurdjumov), another major parasitoid of P. xylostella, showed that neither population could achieve successful parasitism of P. xylostella larvae already parasitized by C. plutellae. However, both O. sokolowskii populations could achieve hyperparasitism by ovipositing into a mid-late stage larva of C. plutellae developing inside the primary host. Contrary to earlier reports, no evidence of intraspecific variations in ability to hyperparasitize between these two populations of O. sokolowskii was found.

E-cadherin expression is silenced by DNA methylation in cervical cancer cell lines and tumours

A previous study showed E-cadherin expression was lost in some cervical cancer cell lines and tumours. This study was designed to clarify the significance of DNA methylation in silencing E-cadherin expression. We examined promoter methylation of E-cadherin in five cervical cancer cell lines and 20 cervical cancer tissues using methylation-specific PCR (MSP) and bisulphite DNA sequencing. The correlation of E-cadherin methylation and expression together with methyltransferase (DNMT1) were further studied. We found that hypermethylation of E-cadherin was involved in five cervical cancer cell lines and 40% (8/20) of cervical cancer tissues. E-cadherin protein was lost in 6/8 (75%) samples and 3/5 (60%) cell lines with promoter methylation. E-cadherin methylation was significantly correlated with increased DNMT1. Using an antisense DNMT1 oligo to transfect into SiHa HeLa C33A cell line, E-cadherin protein was re-expressed. We concluded that loss of E-cadherin expression was in part correlated with DNA methylation and DNMT1 expression in cervical cancer.

Consumers' perceptions of health care: the case of Hong Kong

The health care industry in Hong Kong has undergone major changes in organization as well as philosophy of operation since the 1970s. During this period, the Hong Kong government has also experienced a political transition from colonial status to a special administrative region of Mainland China. Because of the economic downturn in East Asia, including Hong Kong, contraction of public spending has compelled the government to reconsider the alternatives for health care provision in Hong Kong. A number of multinational health care providers have entered this market and operate mainly in the private sector, including solely-owned clinics and alliances with existing hospitals. This paper provides an understanding of the evolution and development of the health care industry in Hong Kong and, on that basis, suggests elements of quality health care from the findings of a survey of patients.

Anti-apoptotic proteins, apoptotic and proliferative parameters and their prognostic significance in cervical carcinoma

The inhibitor of apoptosis proteins (IAP) suppress apoptosis induced by a variety of stimuli. The aims of this study were to: (a) compare the expression of X-linked IAP (Xiap) and Human IAP-2 (Hiap-2) in cervical carcinoma cells and normal cervix, (b) determine the correlation between IAP expression and tumour apoptosis or proliferation, and (c) assess their prognostic significance in cervical carcinomas. Paraffin-embedded tissue sections were retrieved from 77 patients with cervical squamous carcinomas prior to treatments and 47 normal subjects. Tumour apoptosis was determined by terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuracil triphosphate (dUTP) nick-end labelling (TUNEL) and apoptotic index (AI), and the proliferative rate was measured by Ki-67 and mitotic (MI) indices. Immunoreactive Xiap and Hiap-2 were found in both cervical cancer cells and normal tissues. IAP expressions in cancers did not correlate with apoptotic and proliferative parameters, disease stage and patient survival. The lower AI and Ki-67 index were associated with a better survival. In conclusion, the basal expression levels of IAPs have no prognostic significance, but AI and Ki-67 expression are potential prognostic indicators in cervical carcinoma.

Anti-apoptotic proteins, apoptotic and proliferative parameters and their prognostic significance in cervical carcinoma

The inhibitor of apoptosis proteins (IAP) suppress apoptosis induced by a variety of stimuli. The aims of this study were to: (a) compare the expression of X-linked IAP (Xiap) and Human IAP-2 (Hiap-2) in cervical carcinoma cells and normal cervix, (b) determine the correlation between IAP expression and tumour apoptosis or proliferation, and (c) assess their prognostic significance in cervical carcinomas. Paraffin-embedded tissue sections were retrieved from 77 patients with cervical squamous carcinomas prior to treatments and 47 normal subjects. Tumour apoptosis was determined by terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuracil triphosphate (dUTP) nick-end labelling (TUNEL) and apoptotic index (AI), and the proliferative rate was measured by Ki-67 and mitotic (MI) indices. Immunoreactive Xiap and Hiap-2 were found in both cervical cancer cells and normal tissues. IAP expressions in cancers did not correlate with apoptotic and proliferative parameters, disease stage and patient survival. The lower AI and Ki-67 index were associated with a better survival. In conclusion, the basal expression levels of IAPs have no prognostic significance, but AI and Ki-67 expression are potential prognostic indicators in cervical carcinoma.

Epidural lidocaine decreases sevoflurane requirement for adequate depth of anesthesia as measured by the Bispectral Index monitor

BACKGROUND

Epidural anesthesia potentiates sedative drug effects and decreases minimum alveolar concentration (MAC). The authors hypothesized that epidural anesthesia also decreases the general anesthetic requirements for adequate depth of anesthesia as measured by Bispectral Index (BIS).

METHODS

After premedication with 0.02 mg/kg midazolam and 1 microg/kg fentanyl, 30 patients aged 20-65 yr were randomized in a double-blinded fashion to receive general anesthesia with either intravenous saline placebo or intravenous lidocaine control (1-mg/kg bolus dose; 25 microg x kg(-1) x min(-1)). A matched group was prospectively assigned to receive epidural lidocaine (15 ml; 2%) with intravenous saline placebo. All patients received 4 mg/kg thiopental and 1 mg/kg rocuronium for tracheal intubation. After 10 min of a predetermined end-tidal sevoflurane concentration, BIS was measured. The ED50 of sevoflurane for each group was determined by up-down methodology based on BIS less than 50 (MAC(BIS50)). Plasma lidocaine concentrations were measured.

RESULTS

The MAC(BIS50) of sevoflurane (0.59% end tidal) was significantly decreased with lidocaine epidural anesthesia compared with general anesthesia alone (0.92%) or with intravenous lidocaine (1%; P < 0.0001). Plasma lidocaine concentrations in the intravenous lidocaine group (1.9 microg/ml) were similar to those in the epidural lidocaine group (2.0 microg/ml).

CONCLUSIONS

Epidural anesthesia reduced by 34% the sevoflurane required for adequate depth of anesthesia. This effect was not a result of systemic lidocaine absorbtion, but may have been caused by deafferentation by epidural anesthesia or direct rostral spread of local anesthetic within the cerebrospinal fluid. Lower-than-expected concentrations of volatile agents may be sufficient during combined epidural-general anesthesia.

Abnormal expression of pan-ras, c-myc and tp53 in squamous cell carcinoma of cervix: correlation with HPV and prognosis

The aim of this study is to assess, in squamous cell carcinoma of the cervix, the expression of pan-ras, c-myc and tp53 at protein level using an immunohistochemical (IHC) staining method. One hundred and seven patients with squamous cell carcinoma of the cervix were recruited. Fifty-four patients were of stage 1B/2A and 53 were of stage 2B and above. Positive IHC stainings of pan-ras, c-myc and tp53 proteins were detected in 80.4%, 32.7% and 25.2% of cases, respectively. No significant correlation between overexpression of pan-ras and c-myc was detected. However, significantly higher percentages of overexpression of c-myc was found in association with overly expressed tp53 samples (p = 0.014). Human papillomavirus (HPV) was detected in 77.6% of cancers. HPV 16/18 was detected in 72% of cancers. Overexpression of pan-ras and c-myc had no correlation with HPV detection and stage. However, higher percentages of overexpression of tp53 were found in early stage disease (p = 0.017) and in HPV 16/18 positive tumors (p = 0.006). Overexpression of pan-ras, c-myc and tp53 alone or in more than one oncogenes had no prognostic significance on survival.

Effect of insulin on oxygen free radicals and oxidative phosphorylation in liver mitochondria of diabetic rats

AIM

To observe the effects of insulin on liver mitochondrial respiratory function, activity of H+-ATPase, and superoxide anion free radicals production in diabetic rats.

METHODS

Rats were injected iv with alloxan 40 mg/kg to induce diabetes. The liver mitochondrial respiratory function was assayed by measurement of oxygen consumption using a Clark oxygen electrode. Superoxide anion production was assayed using chemiluminescence method. Activities of H+-ATPase were measured by luciferin-luciferase system and inorganic phosphorus's method.

RESULTS

Insulin 1 U/kg sc daily for 9 weeks improved oxidative phosphorylation, respiratory rate state 3 (P < 0.05), respiratory control ration (P < 0.01), and ADP:O ratio (P < 0.01), but there were no obvious effect on respiratory rate state 4 (P > 0.05). In the insulin group, synthesis activity of H+-ATPase was obviously increased (P < 0.05) and hydrolytic activity of H+-ATPase was remarkably decreased (P < 0.01), compared with the diabetes group. Insulin 1 U/kg for 9 weeks apparently decreased the production of O2.- (P < 0.01) in liver mitochondria of diabetic rats.

CONCLUSION

Insulin can prevent the injury from superoxide anion in liver mitochondria, and improve the function of the liver mitochondria oxidative phosphorylation.

Abnormal expression of epidermal growth factor receptor and c-erbB2 in squamous cell carcinoma of the cervix: correlation with human papillomavirus and prognosis

The aim of this study is to assess the expression of epidermal growth factor receptor (EGFR) and c-erbB2 and their correlation with human papillomavirus (HPV) status and prognosis in squamous cell carcinoma of the cervix. The expression of EGFR and c-erbB2 was studied at the protein level using the immunohistochemical (IHC) staining method, at the RNA level using the ribonuclease protection assay and at the DNA level using Southern blot and hybridization method. One hundred and one patients with squamous cell carcinoma of the cervix were recruited. Fifty-one patients were of stage 1B/2A and 50 patients were of stage 2B and above. Positive IHC stainings of EGFR and c-erbB2 proteins were found in 74.2 and 19.8% of cases, respectively. DNA amplifications of EGFR and c-erbB2 genes were detected in 35.4 and 17.2%, respectively. Of the patients showing positive EGFR and c-erbB2 staining, only 39.2 and 25%, respectively, showed DNA amplifications. RNA overexpression of EGFR or c-erbB2 was only detected in 2% of cervical cancers and was associated with positive staining and DNA amplifications. HPV was detected in 79.2% of the cases by HPV consensus primers L1, in 57.4% for HPV 16 and 27.7% for HPV 18. The abnormal expression of EGFR and c-erbB2 had no correlation with HPV detection and had no prognostic significance on survival.

A comparison of ropivacaine with fentanyl to bupivacaine with fentanyl for postoperative patient-controlled epidural analgesia

Ropivacaine for patient-controlled epidural analgesia (PCEA) may facilitate postoperative patient mobilization because it causes less motor block than bupivacaine. Forty patients undergoing abdominal surgery were randomized in a double-blinded manner to the following: 0.05% bupivacaine/4 microg fentanyl, 0.1% bupivacaine/fentanyl, 0.05% ropivacaine/fentanyl, or 0.1% ropivacaine/fentanyl for standardized PCEA. We measured pain scores, side effects, and PCEA consumption for 42 h. Lower-extremity motor function was assessed with electromyography and isometric force dynamometry. Analgesia was equivalent among groups. Local anesthetic use was more in the 0.1% Ropivacaine and 0.1% Bupivacaine groups (77% increase, P = 0.001). Motor function decreased during PCEA (10%-35% decrease from preoperative, P < 0.001) and was equivalent among groups. Eight patients were transiently unable to ambulate. These patients used more local anesthetic (45 vs 33 mg mean, P < 0.05) with additional decrease in motor function (32%, P < 0.004) compared with ambulating patients. Other side effects were mild and equivalent among solutions. PCEA with bupivacaine/fentanyl and ropivacaine/fentanyl as 0.05% or 0.1% solutions appears clinically equipotent. Lower-extremity motor function decreases, but is unlikely to result in prolonged inability to ambulate. Use of a 0.05% solution may be advantageous to decrease local anesthetic use and prevent transient motor block.

IMPLICATIONS

Patient-controlled epidural analgesia with bupivacaine/fentanyl and ropivacaine/fentanyl as either 0.05% or 0.1% solutions are clinically similar. Lower-extremity motor function will decrease with the use of any of these combinations, but is unlikely to result in the inability to walk.

QSAR study of steroid benchmark and dipeptides based on MEDV-13

A molecular electronegativity distance vector based on 13 atomic types, called MEDV-13, is a descriptor for predicting the biological activities of molecules based on the quantitative structure-activity relations (QSAR). The MEDV-13 uses a modified electrotopological state (E-state) index to substitute for the relative eletronegativity (q) of non-hydrogen atoms in the molecule of interest in the MEDV and a topological distance for the relative distance (d) in the MEDV. For an organic molecule containing several chemical elements such as C, H, O, N, S, F, Cl, Br, I, and P, the MEDV-13 includes at best 91 descriptors. Then it is essential to employ a principal component regression (PCR) technique to derive a QSAR model relating the biological activities to the MEDV-13. The MEDV-13 is used to study the QSAR of the corticosteroid-binding globulin (CBG) binding affinity of the steroids and the activity inhibiting angiotensin-converting enzyme (ACE) of dipeptides, and resulting models have a comparable quality to the current three-dimensional (3D) methods such as CoMFA though the MEDV-13 is a descriptor based on two-dimensional topological information.

Frontotemporal orbitozygomatic craniotomy to exposure the cavernous sinus and its surrounding regions. Microsurgical anatomy

BACKGROUND

The microsurgical anatomy of the cavernous sinus and its surrounding regions were examined via frontotemporal orbitozygomatic (FTOZ) craniotomy. Combined with other deep osteotomies, the possibility of exposing the petroclival region and basilar artery was also explored.

METHODS

The study was made on 20 sides of 10 cadaveric specimens fixed with formalin, with the help of the surgical microscope (magnification 5-15).

RESULTS

The FTOZ was performed with frontotemporal and orbitozygomatic flaps. Extradurally, V2, V3, the trigeminal ganglion, the posterior vertical segment of the intracavernous ICA and the VI nerve were exposed by FTOZ craniotomy. By further removal of the petrous apex (Kawase's triangle), exposure could be extended to the petroclival region; with anterior modification of the microscopic light, in 50% of the specimens, exposure reached as low as the convergence of the vertebral arteries. The anterior part of the cavernous sinus and the orbital apex were examined by removing the anterior clinoid process, orbital roof and unroofing the optic canal. Intradurally, the intrapeduncular fossa (upper 1/3 of the clivus) was examined. The intracavernous cranial nerves and vessels were studied via lateral and superior wall approaches. By removing both the anterior and posterior clinoid processes together, in 80% of the specimens, the exposure could be carried as far as the midpoint of the basilar artery.

CONCLUSIONS

FTOZ craniotomy could be used to treat lesions involving the cavernous sinus and its surrounding regions. Incorporated with the petrous apectomy, it could be used to expose the petroclival region and, in selected cases, exposure could be extended to the convergence of the vertebral arteries. Combined with anterior and posterior clinoidectomies, it could also be used to treat midpoint regions of the basilar artery.

[Quantitative structure-retention relationship (QSRR) studies of polychlorinated dibenzofurans (PCDFs) on diverse gas chromatographic stationary phases on a set of novel molecular distance edge vector]

By taking phenyl as a pseudo atom, there are three types of atom in the polychlorinated dibenzofuran (PCDF) molecule, being chlorine atom, oxygen atom and pseudo atom. The chemical structure of PCDF congeners is depicted by a novel molecular distance-edge vector(VMDE, mu in short), developed in our laboratory, which consists of the modified VMDE parameters based on the identical group as a pseudo atom instead of a traditional atom. Furthermore quantitative structure-retention relationships (QSRR) between the new mu vector and gas chromatographic (GC) retention behavior of PCDFs are generated by multiple linear regression method for various stationary phases. Four models, each of which is constructed by using all sample sets, with high correlation coefficient, r > 0.98, are developed for three columns (DB-5, SE-54, OV-101). In order to test the equation stability and prediction ability of each model, it is essential to perform a cross validation (CV) procedure. Satisfactory CV results have been obtained by using one external predicted sample every time with high correlation coefficients, r > 0.97. These results show that the new mu vector has high structural selectivity and good property relativity, and it is easy to calculate the mu vector. And the QSRR models have high relative coefficients, good stability and good predictability.

Prospective experience with a 20-gauge Tuohy needle for lumbar epidural steroid injections: Is confirmation with fluoroscopy necessary?

BACKGROUND AND OBJECTIVES

Small (20-gauge) Tuohy needles have been introduced for epidural steroid injection to optimize patient comfort and decrease the risk of spinal headache. These needles may be less reliable for indentification of the epidural space than standard 17- or 18-gauge needles because of their small size. We prospectively examined the success rate of lumbar epidural steroid placement with loss-of-resistance (LOR) technique compared with fluoroscopy confirmation.

METHODS

One hundred patients without history of lumbar spine surgery were enrolled. A 20-gauge Tuohy needle was placed into the epidural space using LOR to saline. Confidence in epidural placement was recorded (Yes/No). Radiologic contrast was then injected and a fluoroscopic epidurogram interpreted by a blinded radiologist for correct placement, (Yes/No) separate from the clinical process.

RESULTS

Reliability of LOR was less than our "gold standard" of fluoroscopy (P <.004). Sensitivity of LOR was 99% and specificity was 27%. Positive and negative predictive values were 92% and 75%. Increased patient age (>70 years) and male sex were associated with poor reliability of LOR (P <.05).

CONCLUSIONS

In contrast to the reported 99% success rates for epidural placement of standard 17- or 18-gauge Tuohy needles, we observed a success rate of 92%. Small-gauge Tuohy needles are technically more difficult to use than larger needles and may require confirmation with fluoroscopy for correct epidural placement, especially in elderly male patients.

ADL 8-2698, a trans-3,4-dimethyl-4-(3-hydroxyphenyl) piperidine, prevents gastrointestinal effects of intravenous morphine without affecting analgesia

ADL-8-2698 is a novel peripherally restricted opioid antagonist that may selectively prevent opioid-induced gastrointestinal effects without reversing analgesia. Gastrointestinal transit time (lactulose hydrogen breath test) was measured in 14 volunteers with oral and intravenous placebo, oral placebo and intravenous morphine (0.05 mg x kg(-1)), and oral ADL 8-2698 (4 mg) and intravenous morphine (0.05 mg x kg(-1)) in a double blind, cross-over study. Morphine prolonged gastrointestinal transit time from 69 to 103 minutes (P = .005); this was prevented by ADL 8-2698 (P = .004). Postoperatively, 45 patients were randomly assigned in a double-blind fashion to receive ADL 8-2698 (4 mg) or placebo and intravenous morphine (0.15 mg/kg) or to receive oral and intravenous placebo. Analgesia and pupil constriction were measured. Morphine analgesia and pupil constriction were unaffected by ADL 8-2698 and differed from placebo (P < .002). We conclude that ADL 8-2698 prevents morphine-induced increases in gastrointestinal transit time by means of selective peripheral opioid anitagonism without affecting central opioid analgesia.

[Estimation of gas chromatographic retention index for polycyclic aromatic hydrocarbons using VMDE]

A novel molecular distance-edge vector with 6 parameters was calculated for 100 polycyclic aromatic hydrocarbons (PAHs) based on the molecular interaction theory. It was found that there was a good linear relationship between the molecular distance-edge vector (VMDE) and the gas chromatographic retention index for the 100 PAHs, and the molecular modelling equation for the quantitative structure-retention relationship (QSRR) can be expressed as follows: IR = a + b VMDE, n = 100, r = 0.988, where a and b represent regression coefficients. The regression results showed that the molecular distance-edge vector is in good agreement with the results of molecular polarizability index to the gas chromatographic retention index for the polycyclic aromatic hydrocarbons.

[Prediction and estimation on molar response values of alkanes by using molecular path vector]

A new method based on a novel molecular topological index vector, called the molecular path vector (MPV), of alkane molecules is proposed and employed for estimation and prediction of the molar response values of various alkanes. The novel MPV, p = (P1, P2, P3, P4, P5, P6, P7, P8, P9, P10)', which derived directly from the interaction terms of molecular graph, is used to characterize well molecular structures of all alkanes from one through ten or eleven carbon atoms. It showed that there exists very good correlation between the MPV elements and molar response values on both FID and TCD detectors in classical gas chromatography. Based on the given calibration set with different sample numbers and by using the practical multiple linear regression, the quantitative structure-response relationship (QSRR) equations, for the molar response values (SM) on both FID and TCD, are respectively given as follows: SM(FID) = 15.4004881 + 17.9905995 X1 - 0.1652116 X2 - 0.6974103 X3 - 0.8452390 X4 - 0.2671000 X5 - 1.5657273 X6 + 0.0944440 X7, n = 50, m = 7, r = 0.9976, ST = 26.132, SR = 1.965 1, Ev = 99.72%, RMS = 1.801, F = 1231.71 SM(TCD) = 11.9946996 + 29.1490916 X1 - 4.7451669 X2 - 3.7673385 X3 - 1.4948330 X4 - 1.6278831 X5 - 0.7934611 X6 - 3.0566093 X7, n = 32, m = 7, r = 0.9968, ST = 15.72, SR = 1.4310, Ev = 99.59%, RMS = 1.239, F = 531.227 where the independent descriptor variables, X1-X7, refer to the elements, P1, P2, P3, P4, P5, P6, P7 in the molecular path vector for all samples in both FID and TCD training sets; n, r, ST, SR, Ev, RMS and F are the sample number, regression coefficient, total standard deviation, standard residual deviation, explained variance, rooted mean squared error and F-statistic value, respectively. To test both models by using back-propagation neural network (BPNN) with the topological structure NN(7-4-2) and the cross validation through leave-one-out (LOO) procedure, the correlation coefficient of cross validation is over 0.96. Because there exists a quite good linear relationship between the molar responses and molecular path parameters, BPNN (r = 0.989 and 0.968) does not show its nonlinear advantage over multiple linear regression(MLR) (r = 0.9976 and 0.9968) in both presently examined cases, FID and TCD in the GC technique, for molecular modelling and quantitative prediction.

Effect of hypertension on the development of diabetic cardiomyopathy

The effect of hypertension on the progression of diabetic cardiomyopathy was examined by attempting to induce a similar level of diabetes in both spontaneously hypertensive rats (SHR) and Wistar rats. Streptozotocin (STZ) was injected into SHR (45 mg/kg) and Wistar rats (55 mg/kg) before (eight weeks of age) and after (twelve weeks of age) the development of hypertension in the SHR. For both groups of animals, induction of diabetes resulted in depressed weight gain, increased food and fluid consumption, hypoinsulinemia, hyperglycemia, and hypertriglyceridemia. For the rats injected at eight weeks of age, an oral glucose tolerance test (OGTT) demonstrated that although the SHR were significantly less diabetic than Wistar rats, the degree of cardiac dysfunction was equivalent in both strains. These results suggest that hypertension was interacting with the diabetic condition to impair cardiac performance. Injecting SHR at twelve weeks of age increased the severity of diabetes but interestingly did not depress heart function compared with the non-diabetic SHR group. Injecting Wistar rats at this age also increased the severity of diabetes, but unlike the SHR diabetic animals, these rats still had impaired cardiac performance. These results suggest that hypertension exacerbates the cardiac dysfunction seen during diabetes, especially when SHR rats are injected with STZ prior to the elevation of blood pressure. Moreover, in the SHR, the development of LV hypertrophy at the time of STZ injection may have compensated for the damaging effects of diabetes on the myocardium, thereby enabling the heart to perform normally.

A comparison of spinal, epidural, and general anesthesia for outpatient knee arthroscopy

We compared general, epidural, and spinal anesthesia for outpatient knee arthroscopy (excluding anterior cruciate ligament repairs). Forty-eight patients (ASA physical status I-III) were randomized to receive either propofol-nitrous oxide general anesthesia with a laryngeal mask airway with anesthetic depth titrated to a bispectral index level of 40-60, 15-20 mL of 3% 2-chloroprocaine epidural, or 75 mg of subarachnoid procaine with 20 microg fentanyl. All patients were premedicated with <0.035 mg/kg midazolam and <1 microg/kg fentanyl and received intraarticular bupivacaine and 15-30 mg of IV ketorolac during the procedure. Recovery times, operating room turnover times, and patient satisfaction were recorded by an observer using an objective scale for recovery assessment and a verbal rating scale for satisfaction. Statistical analysis was performed with analysis of variance and chi(2). Postanesthesia care unit discharge times for the general and epidural groups were similar (general = 104+/-31 min, epidural = 92+/-18 min), whereas the spinal group had a longer recovery time (146+/-52 min) (P = 0.0003). Patient satisfaction was equally good in all three groups (P = 0.34). Room turnover times did not differ among groups (P = 0.16). There were no anesthetic failures or serious adverse events in any group. Pruritus was more frequent in the spinal group (7 of 16 required treatment) than in the general or epidural groups (no pruritus) (P<0.001). We conclude that epidural anesthesia with 2-chloroprocaine provides comparable recovery and discharge times to general anesthesia provided with propofol and nitrous oxide. Spinal anesthesia with procaine and fentanyl is an effective alternative and is associated with a longer discharge time and increased side effects.

IMPLICATIONS

For outpatient knee arthroscopy, anesthesia can be provided adequately with regional or general anesthesia. Epidural and general anesthesia provide equal recovery times and patient satisfaction, whereas spinal anesthesia may prolong recovery and have increased side effects. The choice of anesthesia may depend primarily on the patient's interest in being alert or asleep during the procedure.

Sedation during spinal anesthesia

BACKGROUND

Central neuraxial anesthesia has been reported to decrease the dose of both intravenous and inhalational anesthetics needed to reach a defined level of sedation. The mechanism behind this phenomenon is speculated to be decreased afferent stimulation of the reticular activating system. The authors performed a two-part study (nonrandomized pilot study and a subsequent randomized, double-blind, placebo-controlled study) using the Bispectral Index (BIS) monitor to quantify the degree of sedation in unmedicated volunteers undergoing spinal anesthesia.

METHODS

Twelve volunteers underwent BIS monitoring and observer sedation scoring (Observer's Assessment of Alertness/Sedation Scale [OAA/S]) before and after spinal anesthesia with 50 mg hyperbaric lidocaine, 5%. Subsequently, 16 volunteers blinded to the study were randomized to receive spinal anesthesia with 50 mg hyperbaric lidocaine, 5% (n = 10) or placebo (n = 6) and underwent BIS and OAA/S monitoring.

RESULTS

In part I, significant changes in BIS scores of the volunteers occurred progressively (P = 0.003). The greatest variations from baseline BIS measurement occurred at 30 and 70 min. In part II, there were significant decreases in OAA/S and self-sedation scores for patients receiving spinal anesthesia versuscontrol patients (P = 0.04 and 0. 01, respectively). The greatest decrease in OAA/S scores occurred at 60 min. BIS scores were similar between groups (P = 0.4).

CONCLUSIONS

Spinal anesthesia is accompanied by significant sedation progressively when compared with controls as measured by OAA/S and self-sedation scores. This effect was not related to block height. The late sedation observed by OAA/S at 60 min may indicate a second mechanism of sedation, such as delayed rostral spread of local anesthetics. BIS was not a sensitive measure of the sedation associated with spinal anesthesia in the randomized, blinded portion of this study.

Modelling development time of Lipaphis erysimi (Hemiptera: Aphididae) at constant and variable temperatures

The development period from birth to adult of virginoparae of the turnip aphid, Lipaphis erysimi (Kaltenbach), at 14 constant, 15 alternating and 15 natural temperature regimes were modelled to determine mathematical functions for simulating aphid development under a wide range of natural conditions. The day-degree model, the logistic equation, and the Wang model were used to describe the relationships between temperature and development rate at constant and alternating temperatures. The three models were then used with a Weibull function describing the distribution of development times, to simulate the development of individuals of cohorts at natural temperature regimes. Comparison of the observed with simulated distributions of adult emergence indicates that all three models can simulate the development of L. erysimi equally well when temperature does not go below 6 degrees C (the notional low temperature threshold of the day-degree model) or above 30 degrees C. When accumulation of temperatures below 6 degrees C becomes substantial, only the logistic curve offers accurate simulations; the other two models give falsely longer durations of development. When accumulation of temperatures above 30 degrees C becomes substantial, the logistic curve and the Wang model offer more accurate simulations than the day-degree model, which tends to produce shorter durations of development. Further analysis of the data reveals that development rate of this aphid at a given unfavourable high temperature may vary with time. Methods for accurately simulating the development time of L. erysimi in the field are suggested. The significance of modelling insect development at low and high temperatures by non-linear models is discussed.

Rapid assay of A1c-type glycosylated hemoglobin in blood of diabetic rats using fast protein liquid chromatography

AIM

To develop a fast protein liquid chromatography (FPLC) method for the assay of Alc-type glycosylated hemoglobin in diabetic rats.

METHODS

Venous blood was collected from rats. After the erythrocytes were washed and sedimented, the hemolysate was prepared and diluted with isotonic saline as a sample for the assay. Samples were then separated on Mono_S_HR_5/5 cation exchange column by a lithium chloride gradient elution system. The Alc-type glycosylated hemoglobin was monitored by measuring the absorbance at 415 nm.

RESULTS

The Alc-type glycosylated hemoglobin was well separated from total hemoglobin. The average HbAlc amount in diabetic rats was determined to be (3.6% +/- 0.6%, n = 7), while the corresponding figure in normal rats was (1.4% +/- 0.4%, n = 7, P < 0.01).

CONCLUSION

This FPLC method is easy, rapid and reproducible, and can be used for an assay of diabetic rat HbAlc to evaluate and screen new drugs for diabetes mellitus therapy.

New developments in spinal anesthesia

Spinal anesthesia can be used effectively and efficiently for a variety of cases in both the inpatient and the ambulatory surgery setting. Choice of agent, dose, distribution, use of adjuncts, and occasionally the use of continuous spinal anesthesia can tailor the spinal anesthetic to a specific type and duration of surgery. Although spinal anesthesia is extremely safe, adherence of new guidelines for patients receiving anticoagulant drugs, LMWH in particular, may minimize the risk of neurologic injury from spinal bleeding. At present, intrathecal adjuncts, such as neostigmine and clonidine used with local anesthetics, have shown limited usefulness, whereas lipophilic opioids, such as fentanyl, appear to increase duration and quality of spinal block without increasing the time to recovery. In the future, shorter-acting local anesthetics, possibly in conjunction with continuous catheter technologies, may reduce recovery times after spinal anesthesia without increasing risk. Spinal agents with long-acting analgesic properties that do not produce sensorimotor deficits may go beyond the immediate perioperative period and relieve postoperative pain. Currently there is controversy surrounding the use of spinal lidocaine and the occurrence of TNS, especially in the outpatient setting. The prudent use of small-dose bupivacaine and possibly procaine may reduce this risk, further supporting the use of spinal anesthesia for ambulatory as well as inpatient surgical procedures.

Procaine compared with lidocaine for incidence of transient neurologic symptoms

BACKGROUND AND OBJECTIVES

Transient neurologic symptoms (TNS) have been reported to occur after 16% to 40% of ambulatory lidocaine spinal anesthetics. Patient discomfort and the possibility of underlying lidocaine neurotoxicity have prompted a search for alternative local anesthetic agents. We compared the incidence of TNS with procaine or lidocaine spinal anesthesia in a 2:1 dose ratio.

METHODS

Seventy outpatients undergoing knee arthroscopy were blindly randomized to receive either 100 mg hyperbaric procaine or 50 mg hyperbaric lidocaine. An interview by a blinded investigator established the presence or absence of TNS, defined as pain in the buttocks or lower extremities beginning within 24 hours of surgery. Onset of sensory and motor block, patient discomfort, supplemental anesthetics, and side effects were recorded by the unblinded managing anesthesia team. Anesthetic adequacy was determined from these data by a single blinded investigator. Hospital discharge time was recorded from the patient record. Groups were compared using appropriate statistics with a P < .05 considered significant.

RESULTS

TNS occurred in 6% of procaine patients versus 31% of lidocaine patients (P = .007). Sensory block with procaine and lidocaine was similar, while motor block was decreased with procaine (P < .05). A trend toward a higher rate of block inadequacy (17% v 3%, P = .11) and intraoperative nausea (17% v 3%, P = .11) occurred with procaine. Average hospital discharge time with procaine was increased by 29 minutes (P < .05).

CONCLUSIONS

The incidence of TNS was substantially lower with procaine than with lidocaine. However, procaine resulted in a lower overall quality of anesthesia and a prolonged average discharge time. If the shortfalls of procaine as studied can be overcome, it may provide a suitable alternative to lidocaine for outpatient spinal anesthesia to minimize the risk of TNS.

Homozygous arginine at codon 72 of p53 has no prognostic significance in cervical cancer

Mutation of p53, a tumour suppressor gene, is uncommon in cervical cancer but the detection of human papillomavirus (HPV) DNA in cervical cancer is common. The findings of increased susceptibility to degradation of p53 by E6 protein of HPV16/18 in cervical cancer with homozygous arginine at codon 72 (HA72) of p53 led to this study on whether cervical cancers with HA72 were more aggressive with the increase in the rate of loss of p53 function. In 102 cervical cancers, 76.5% were HPV16/18 positive and 30% had HA72. No survival difference was detected between HA72 and non-HA72 tumours irrespective of HPV16/18 status. Furthermore, the detection of HPV16/18 in cervical cancer was found not to be of prognostic significance in this study.

Spinal nerve function in five volunteers experiencing transient neurologic symptoms after lidocaine subarachnoid anesthesia

The etiology of transient neurologic symptoms (TNS) after 5% lidocaine spinal anesthesia remains undetermined. Previous case reports have shown that patients acutely experiencing TNS have no abnormalities on neurologic examination or magnetic resonance imaging. The aim of our study was to determine whether volunteers with TNS would exhibit abnormalities in spinal nerve electrophysiology. Twelve volunteers with no history of back pain or neurologic disease underwent baseline electromyography (EMG), nerve conduction studies, and somatosensory-evoked potential (SSEP) testing. Then, the volunteers were administered 50 mg of 5% hyperbaric lidocaine spinal anesthesia and were placed in a low lithotomy position (legs on four pillows). The next day, all volunteers underwent follow-up EMG, nerve conduction, and SSEP testing and were questioned and examined for the presence of complications including TNS (defined as pain or dysthesia in one or both buttocks or legs occurring within 24 h of spinal anesthesia). Volunteers who had TNS underwent additional EMG testing 4-6 wk later. Five of the 12 volunteers reported TNS. No volunteer had an abnormal EMG, nerve conduction study, or SSEP at 24 h follow up, nor were there any changes in EMG studies at delayed testing in the five volunteers experiencing TNS. On statistical analysis, the right peroneal and the right tibial nerve differed significantly for all volunteers from pre- to postspinal testing. When comparing pre- and postspinal testing of the TNS and non-TNS volunteers, statistically significant changes occurred in the nerve conduction tests of the right peroneal and left tibial nerve. There was no difference in measurements of F response, H reflex latency, amplitude, or velocity for either leg. Multivariate analysis of variance showed no significant difference between TNS and non-TNS volunteers for the changes in the nine nerve conduction tests when considered together (P = 0.4). We conclude that acute TNS after lidocaine spinal anesthesia did not result in consistent abnormalities detectable by EMG, nerve conduction studies, or SSEP in five volunteers.

IMPLICATIONS

Electrophysiologic testing in volunteers experiencing transient neurologic symptoms is not abnormal.

Sputum induction to improve the diagnostic yield in patients with suspected pulmonary tuberculosis

OBJECTIVE

To evaluate the utility of sputum induction in the large-scale tuberculosis control program.

METHODS

Prospective study on sputum induction for improving the diagnostic yield of pulmonary tuberculosis, and estimation of the direct costs for sputum induction.

RESULTS

Of 1,648 tuberculosis suspects with poor or absent sputum production, induced sputum was smear-positive in 558 patients (353 previously smear-negative, 97 inadequate sputum and 108 unproductive). The direct cost per induced sputum was US $0.37.

CONCLUSION

Sputum induction is an effective, low-cost, and simple technique for improving the smear-positive case detection rate in a tuberculosis control program.

Does epidural anesthesia have general anesthetic effects? A prospective, randomized, double-blind, placebo-controlled trial

BACKGROUND

Clinically, patients require surprisingly low end-tidal concentrations of volatile agents during combined epidural-general anesthesia. Neuraxial anesthesia exhibits sedative properties that may reduce requirements for general anesthesia. The authors tested whether epidural lidocaine reduces volatile anesthetic requirements as measured by the minimum alveolar concentration (MAC) of sevoflurane for noxious testing cephalad to the sensory block.

METHODS

In a prospective, randomized, double-blind, placebo-controlled trial, 44 patients received 300 mg epidural lidocaine (group E), epidural saline control (group C), or epidural saline-intravenous lidocaine infusion (group I) after premedication with 0.02 mg/kg midazolam and 1 microg/kg fentanyl. Tracheal intubation followed standard induction with 4 mg/kg thiopental and succinylcholine 1 mg/kg. After 10 min or more of stable end-tidal sevoflurane, 10 s of 50 Hz, 60 mA tetanic electrical stimulation were applied to the fifth cervical dermatome. Predetermined end-tidal sevoflurane concentrations and the MAC for each group were determined by the up-and-down method and probit analysis based on patient movement.

RESULTS

MAC of sevoflurane for group E, 0.52+/-0.18% (+/- 95% confidence interval [CI]), differed significantly from group C, 1.18+/-0.18% (P < 0.0005), and from group I, 1.04+/-0.18% (P < 0.001). The plasma lidocaine levels in groups E and I were comparable (2.3+/-1.0 vs. 3.0+/-1.2 microg/ml +/- SD).

CONCLUSIONS

Lidocaine epidural anesthesia reduced the MAC of sevoflurane by approximately 50%. This MAC sparing is most likely caused by indirect central effects of spinal deafferentation and not to systemic effects of lidocaine or direct neural blockade. Thus, lower concentrations of volatile agents than those based on standard MAC values may be adequate during combined epidural-general anesthesia.

Proto-oncogenes and p53 protein expression in normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia

The aim of this study was to study the protein expression of six proto-oncogenes (epidermal growth factor receptor (EGFR), c-fms, c-myc, c-kit, c-erbB-2 and pan-ras) and one tumour suppressor gene (TP53), by immunohistochemical staining of normal cervical stratified squamous epithelium and cervical intra-epithelial neoplasia (CIN). Paraffin sections of 45 normal cervical specimens, 38 CIN grade one (CIN1), 37 CIN2 and 43 CIN3 were studied. An immunohistochemical (IHC) score was derived from the intensity of staining and the percentages of cells stained. In normal cervical specimens, a higher IHC score was found with EGFR and c-fms in superficial (S), intermediate (I) and parabasal (PB) cells compared with basal cells. In contrast, a higher IHC score was found with c-erbB-2 in basal cells in normal cervical specimens. Dysplastic cells in CIN had a higher IHC score with c-myc and c-erbB-2 than normal S/I and PB cells. Dysplastic cells had a higher score with EGFR than normal basal cells. However, a higher IHC score with EGFR and c-fms was found in normal S/I cells than dysplastic cells. These findings suggested that EGFR and c-fms were activated in more differentiated normal cells but were less active in less differentiated normal basal cells. However, EGFR was reactivated in dysplastic cells. Meanwhile, c-erbB-2 was activated in less differentiated normal basal cells and dysplastic cells, and was less active in differentiated normal cells. c-myc was activated in dysplastic cells. c-fms was more active in more differentiated normal cells and was not activated in less differentiated or dysplastic cells. c-kit, pan-ras and TP53 were not activated in normal nor dysplastic cervical cells. These results suggest EGFR, c-erbB-2 and c-myc may be important proto-oncogenes in CIN and that antibodies or anti-genes targeted against them may alter the progress of CIN to invasive cancer.

Risk of cervical cancer is not increased in Chinese carrying homozygous arginine at codon 72 of p53

Homozygous arginine at codon 72 (HA72) of p53 was found in 22% of normal cervices and 30.0% of cervical cancers and no significant difference was detected between normal and cervical cancer with or without HPV 16/18. There was no correlation between HA72 and risk of cervical cancer in Chinese.

Cooperation of a "reactive oxygen cycle" with the Q cycle and the proton cycle in the respiratory chain--superoxide generating and cycling mechanisms in mitochondria

Based on our recent findings concerning the generating, partitioning, targeting, and functioning of superoxide in mitochondria, a hypothetical model involving a "reactive oxygen cycle" in the respiratory chain has been proposed (Liu and Huang, 1991, 1996; Liu et al., 1996; Liu, 1997, 1998) This model emphasizes that during State 4 respiration, an interaction between an electron leak (a branch of electron transfer directly from the respiratory chain to form O2*-, but not H2O) and a proton leak (a branch pathway which utilizes delta muH+ to produce heat, but not ATP) may take place in cooperation with the Q and proton cycles in mitochondria through the consumption of H+ by O2*- anions to form a protonated perhydroxyl radical, HO2, which is directly permeable across the inner mitochondrial membrane and induces proton leakage and a decrease of delta muH+. O2*- generation in the mitochondrial respiratory chain and its cycling across the inner membrane may have the role of an endogenous protonophore in regulating and partitioning energy transduction and heat production, as well as in pathogenesis of mitochondrial diseases, aging, and apoptosis. The present article summarizes the supporting experimental evidence obtained in this laboratory and presents a brief description of the theoretical basis of this model.

Hyperbaric spinal ropivacaine: a comparison to bupivacaine in volunteers

BACKGROUND

Ropivacaine is a newly introduced local anesthetic that may be a useful alternative to low-dose bupivacaine for outpatient spinal anesthesia. However, its relative potency to bupivacaine and its dose-response characteristics are unknown. This double-blind, randomized, crossover study was designed to determine relative potencies of low-dose hyperbaric spinal ropivacaine and bupivacaine and to assess the suitability of spinal ropivacaine for outpatient anesthesia.

METHODS

Eighteen healthy volunteers were randomized into three equal groups to receive one spinal administration with bupivacaine and a second with ropivacaine, of equal-milligram doses (4, 8, or 12 mg) of 0.25% drug with 5% dextrose. The duration of blockade was assessed with (1) pinprick, (2) transcutaneous electrical stimulation, (3) tolerance to high tourniquet, (4) electromyography and isometric force dynamometry, and (5) achievement of discharge criteria. Differences between ropivacaine and bupivacaine were assessed with linear and multiple regression. P < 0.05 was considered significant.

RESULTS

Ropivacaine and bupivacaine provided dose-dependent prolongation of sensory and motor block and time until achievement of discharge criteria (R2 ranges from 0.33-0.99; P values from < 0.001 through 0.01). Spinal anesthesia with ropivacaine was significantly different from bupivacaine and was approximately half as potent for all criteria studied. A high incidence of back pain (28%; P = 0.098) was noted after intrathecal ropivacaine was given.

CONCLUSION

Ropivacaine is half as potent and in equipotent doses has a similar profile to bupivacaine with a higher incidence of side effects. Low-dose hyperbaric spinal ropivacaine does not appear to offer an advantage over bupivacaine for use in outpatient anesthesia.

The neurotoxicity of drugs given intrathecally (spinal)

Overall, most spinal drugs in clinical use have been poorly studied for spinal cord and nerve root toxicity. Laboratory studies indicate that all local anesthetics are neurotoxic in high concentrations and that lidocaine and tetracaine have neurotoxic potential in clinically used concentrations. However, spinal anesthesia (including lidocaine and tetracaine) has a long and enviable history of safety. Spinal analgesics such as morphine, fentanyl, sufentanil, clonidine, and neostigmine seem to have a low potential for neurotoxicity based on laboratory and extensive clinical use. Most antioxidants, preservatives, and excipients used in commercial formulations seem to have a low potential for neurotoxicity. In addition to summarizing current information, we hope that this review stimulates future research on spinal drugs to follow a systematic approach to determining potential neurotoxicity. Such an approach would examine histologic, physiologic, and behavioral testing in several species, followed by cautious histologic, physiologic, and clinical testing in human volunteers and patients with terminal cancer refractory to conventional therapy.

Comparison of three solutions of ropivacaine/fentanyl for postoperative patient-controlled epidural analgesia

BACKGROUND

Ropivacaine, 0.2%, is a new local anesthetic approved for epidural analgesia. The addition of 4 microg/ml fentanyl improves analgesia from epidural ropivacaine. Use of a lower concentration of ropivacaine-fentanyl may further improve analgesia or decrease side effects.

METHODS

Thirty patients undergoing lower abdominal surgery were randomized in a double-blinded manner to receive one of three solutions: 0.2% ropivacaine-4 microg fentanyl 0.1% ropivacaine-2 microg fentanyl, or 0.05% ropivacaine-1 microg fentanyl for patient-controlled epidural analgesia after standardized combined epidural and general anesthesia. Patient-controlled epidural analgesia settings and adjustments for the three solutions were standardized to deliver equivalent drug doses. Pain scores (rest, cough, and ambulation), side effects (nausea, pruritus, sedation, motor block, hypotension, and orthostasis), and patient-controlled epidural analgesia consumption were measured for 48 h.

RESULTS

All three solutions produced equivalent analgesia. Motor block was significantly more common (30 vs. 0%) and more intense with the 0.2% ropivacaine-4 microg fentanyl solution. Other side effects were equivalent between solutions and mild in severity. A significantly smaller volume of 0.2% ropivacaine-4 microg fentanyl solution was used, whereas the 0.1% ropivacaine-2 microg fentanyl group used a significantly greater amount of ropivacaine and fentanyl.

CONCLUSIONS

Lesser concentrations of ropivacaine and fentanyl provide comparable analgesia with less motor block despite the use of similar amounts of ropivacaine and fentanyl. This finding suggests that concentration of local anesthetic solution at low doses is a primary determinant of motor block with patient-controlled epidural analgesia after lower abdominal surgery.

Abnormal expression or mutation of TP53 and HPV in vulvar cancer

HPV (human papillomavirus) plays an important role in cervical cancer and may also play a role in vulvar cancer. TP53 mutation is common in a variety of cancers but its role in vulvar cancer is not well established. The aim of this study was to assess the prevalence of HPV infection and TP53 mutation as well as their correlation in vulvar cancer. Also, HPV detection and abnormal p53 expression were assessed in relation to age, co-existing vulvar intraepithelial neoplasia and vulvar dystrophy. Forty-eight samples of vulvar cancer were studied. DNA was extracted from formalin-fixed paraffin embedded tissue for polymerase chain reaction/Southern blot study with HPV 16 and 18 and L1 primers. Paraffin sections were immunostained (IHS) for p53 protein using three antibodies, p1801, CM1 and DO7. The p53 mutation was also screened using polymerase chain reaction (PCR) single-stranded conformation polymorphism (SSCP) and confirmed by sequencing. Overall, HPV was detected in 48% (23/48), of which 96% (22/23) were HPV 16 or 18. By IHS, p53 overexpression was detected in 46% of cases whilst TP53 mutations were identified in 21%. In HPV positive and negative tumours, p53 abnormal expression was detected in 39% and 52%, respectively, and TP53 mutation was found in 22% and 20%, respectively. Mutations were mainly found at codons 273 and 204. Age was not found to be associated with HPV detection. However, the presence of HPV (71%) or absence of abnormal p53 expression (65%) were higher in tumours with VIN3, but were not correlated with dystrophy.

Dose-response effects of spinal neostigmine added to bupivacaine spinal anesthesia in volunteers

BACKGROUND

Intrathecal adjuncts often are used to enhance small-dose spinal bupivacaine for ambulatory anesthesia. Neostigmine is a novel spinal analgesic that could be a useful adjunct, but no data exist to assess the effects of neostigmine on small-dose bupivacaine spinal anesthesia.

METHODS

Eighteen volunteers received two bupivacaine spinal anesthetics (7.5 mg) in a randomized, double-blinded, crossover design. Dextrose, 5% (1 ml), was added to one spinal infusion and 6.25, 12.5, or 50 microg neostigmine in dextrose, 5%, was added to the other spinal. Sensory block was assessed with pinprick; by the duration of tolerance to electric stimulation equivalent to surgical incision at the pubis, knee, and ankle; and by the duration of tolerance to thigh tourniquet. Motor block at the quadriceps was assessed with surface electromyography. Side effects (nausea, vomiting, pruritus, and sedation) were noted. Hemodynamic and respiratory parameters were recorded every 5 min. Dose-response relations were assessed with analysis of variance, paired t tests, or Spearman rank correlation.

RESULTS

The addition of 50 microg neostigmine significantly increased the duration of sensory and motor block and the time until discharge criteria were achieved. The addition of neostigmine produced dose-dependent nausea (33-67%) and vomiting (17-50%). Neostigmine at these doses had no effect on hemodynamic or respiratory parameters.

CONCLUSIONS

The addition of 50 microg neostigmine prolonged the duration of sensory and motor block. However, high incidences of side effects and delayed recovery from anesthesia with the addition of 6.25 to 50 microg neostigmine may limit the clinical use of these doses for outpatient spinal anesthesia.

Dilution of spinal lidocaine does not alter the incidence of transient neurologic symptoms

BACKGROUND

Although it has been suggested that the dilution of 5% hyperbaric lidocaine before injection for spinal anesthesia may decrease the incidence of transient neurologic symptoms, previous studies have not noted a decreased incidence between 5% and 2% lidocaine. The aim of the current study was to determine whether the incidence of transient neurologic symptoms could be altered by further diluting spinal lidocaine from 2.0% to 0.5%.

METHODS

One hundred nine patients with American Society of Anesthesiologists physical status 1 or 2 undergoing outpatient knee arthroscopy were randomized in a double-blind fashion to receive 50 mg hyperbaric spinal lidocaine as a 2.0%, 1.0%, or 0.5% concentration. On the third postoperative day, patients were contacted by a blinded investigator and questioned regarding the incidence of postoperative complications, including transient neurologic symptoms, defined as pain or dysthesia in one or both buttocks or legs occurring within 24 h of surgery.

RESULTS

The incidence of transient neurologic symptoms did not differ among patients receiving 2.0% (incidence of 15.8%), 1.0% (incidence of 22.2%), and 0.5% (incidence of 17.1%) lidocaine (P = 0.756).

CONCLUSIONS

For ambulatory patients undergoing arthroscopy, the incidence of transient neurologic symptoms is not reduced by decreasing spinal lidocaine concentrations from 2.0% to 1.0% or 0.5%. The incidences of transient neurologic symptoms with the 0.5%, 1.0%, and 2.0% solutions are similar to previously reported incidences for 5.0% lidocaine, suggesting that dilution of lidocaine from 5.0% to 0.5% does not change the incidence of these symptoms.

Clinical significance of telomerase activation and telomeric restriction fragment (TRF) in cervical cancer

Telomerase activation was examined in 50 cases of cervical cancer, 27 normal cervix and five cervical cancer cell lines using the sensitive polymerase chain reaction (PCR)-based TRAP (telomeric repeat amplification protocol) assay. Telomeric restriction fragment (TRF) length of these specimens was measured by Southern hybridisation. Telomerase activation was common in cervical cancers and was detected in 46/50 cases (92%). Telomerase activity was weak in normal cervix and was detected only in 2/27 cases (7.4%). Telomerase activity was detected in all stages of cervical cancer suggesting that it is an early event in cancer progression. The clinical significance of telomerase activation was analysed in 47 squamous cell carcinoma of the cervix. High telomerase activity was more frequently detected in advanced diseases (100% in stage III and stage IV cervical cancers combined) compared with early diseases (68.6% in stage I and stage II cancers combined). The difference was statistically significant (P < 0.02). Telomerase activity was not statistically correlated with other clinical parameters examined. This is the first report of telomeric length in human cervical cancer. Both shortening and elongation of TRF length in cervical cancers was observed. Advanced cervical cancers tended to have a wider range of variation of TRF length compared with early disease and normal cervix. There was no obvious relationship between TRF length and the clinical parameters examined including clinical staging, differentiation status of tumour, human papilloma virus (HPV) infection, recurrence rate, tumour size and invasion depth. The clinical significance of TRF length appears to be limited in cervical cancers. Our results indicate that telomerase activity is closely associated with tumour cells and may be useful as a marker for detection of tumour cells in cervical biopsies.

Peripheral nerve blocks improve analgesia after total knee replacement surgery

Total knee replacement (TKR) produces severe postoperative pain. Peripheral nerve blocks can be used as analgesic adjuncts for TKR, but the efficacy of femoral nerve blocks alone is controversial. The sciatic nerve innervates posterior regions of the knee; thus, performance of both sciatic and femoral nerve blocks may be necessary to improve analgesia after TKR. We performed this study to determine whether peripheral nerve blocks improve analgesia after TKR. In a randomized, double-blind fashion, 36 patients undergoing TKR received either femoral, sciatic-femoral, or sham nerve blocks after a standardized spinal anesthetic. Further postoperative analgesia was provided by patient-controlled i.v. morphine and ketorolac. Pain at rest and with physical therapy, morphine use, nausea, pruritus, sedation, and patient satisfaction were assessed. Patients receiving peripheral nerve blocks reported better analgesia at rest for at least 8 h after transfer to the hospital ward (P < 0.05). Morphine use was decreased by approximately 50% in the peripheral nerve block groups until the second postoperative day (P < 0.02). Side effect profiles and patient satisfaction were similar between groups. We conclude that femoral nerve blocks improve analgesia and decrease morphine use after TKR. The addition of a sciatic nerve block to the femoral nerve block did not further improve analgesic efficacy.

IMPLICATIONS

Performance of femoral nerve blocks improves analgesia and decreases the need for morphine after total knee replacement surgery. The addition of a sciatic nerve block to the femoral nerve block does not provide additional benefits.

Lumbosacral cerebrospinal fluid volume is the primary determinant of sensory block extent and duration during spinal anesthesia

BACKGROUND. Injection of local anesthetic into cerebrospinal fluid (CSF) produces anesthesia of unpredictable extent and duration. Although many factors have been identified that affect the extent of spinal anesthesia, correlations are relatively poor and the extent of spread remains unpredictable. This study was designed to determine whether variability in the volume of lumbosacral CSF among individuals is a contributing factor in the variability of spinal anesthesia.

METHODS

Spinal anesthesia was administered to 10 healthy volunteers with 50 mg lidocaine in 7.5% dextrose. The technique was standardized to minimize variability in factors known to affect the distribution of spinal anesthesia. The extent of sensory anesthesia was assessed by pin-prick and by transcutaneous electrical stimulation. Motor blockade was assessed in the quadriceps and gastrocnemius muscles by force dynamometry. Duration of anesthesia was assessed by pinprick, transcutaneous electrical stimulation, and duration of motor blockade. Lumbosacral CSF volumes were calculated from low thoracic, lumbar, and sacral axial magnetic resonance images obtained at 8-mm increments. Volumes of CSF were correlated with measures of extent and duration of spinal anesthesia using the Kendall rank correlation test.

RESULTS

Lumbosacral CSF volumes ranged from 42.7 to 81.1 ml. Volumes of CSF correlated with pin-prick assessments of peak sensory block height (P = 0.02) and duration of surgical anesthesia (as assessed by the duration of tolerance to transcutaneous electrical stimulation at the ankle (P < 0.05).

CONCLUSIONS

Variability in lumbosacral CSF volume is the most important factor identified to date that contributes to the variability in the spread of spinal sensory anesthesia.

Quantitative analysis of respiratory, motor, and sensory function after supraclavicular block

The incidence and clinical significance of hemidiaphragmatic paresis after supraclavicular block of the brachial plexus is unknown. Eight healthy volunteers received a supraclavicular block with a standard technique using 30 mL of 1.5% lidocaine. Respiratory function was assessed with ultrasound of the diaphragm, respiratory inductive plethysmography (RIP), and pulmonary function tests (PFT) every 20 min. Sensory block was assessed with pinprick and motor block with isometric force dynamometry every 20 min. Four of eight subjects demonstrated hemidiaphragmatic paresis on both ultrasound and RIP. No subject experienced changes in PFT values or subjective symptoms of respiratory difficulty. Motor and sensory blockade outlasted hemidiaphragmatic paresis. These results are contrasted to the often symptomatic, 100% incidence of hemidiaphragmatic paresis seen after interscalene block. In this study of healthy volunteers, supraclavicular block was associated with a 50% incidence (95% confidence interval 14-86) of hemidiaphragmatic paresis that was not accompanied by clinical evidence of respiratory compromise.

IMPLICATIONS

Interscalene block is always associated with diaphragmatic paralysis and respiratory compromise. The significance of these side effects after supraclavicular block is unknown. Using sensitive measures of respiratory function, we determined that diaphragmatic paralysis occurs less often with the supraclavicular approach and is not associated with respiratory difficulties in healthy subjects.

Premedication with fentanyl and midazolam decreases the reliability of intravenous lidocaine test dose

This study was performed to determine whether premedication with midazolam and fentanyl prevents reliable detection of an i.v. lidocaine test dose. Thirty ASA physical status I or II patients received either 3 mL of saline or 1.5 mg of midazolam (1.5 mL) plus 75 microg of fentanyl (1.5 mL) i.v. in a randomized, double-blind fashion. Five minutes later, lidocaine 1 mg/kg was injected i.v. At 1.5 min before and every minute after lidocaine administration, each subject was questioned regarding the presence of four symptoms of systemic lidocaine toxicity. Any new tinnitus, perioral numbness, metallic taste, or light-headedness within 5 min after lidocaine administration was considered a positive response. All 15 patients in the saline group (100% sensitivity) had a positive response to i.v. lidocaine, but only 9 of 15 patients in the sedation group had a positive response (60% sensitivity; P = 0.017). We conclude that midazolam and fentanyl premedication decreases the reliability of subjective detection of i.v. lidocaine.

IMPLICATIONS

Anesthesiologists often rely on subjective symptoms to prevent local anesthetic toxicity while performing regional anesthesia. Sedatives are often administered during the administration of regional anesthesia. This study demonstrates that typical sedation decreases the reliability of detection of local anesthetic toxicity by subjective symptoms.

Standardized perioperative care protocols and reduced length of stay after colon surgery

BACKGROUND

Recent studies have suggested that critical pathways and standard order sets decrease hospital length of stay and improve quality of care. A recently conducted prospective, randomized study at our institution found that patients undergoing elective colon resections had earlier return of bowel function if perioperative epidural anesthesia and analgesia were provided. All patients in the study were also placed on a standardized perioperative regimen. We hypothesized that the standardized perioperative protocol used in this study contributed to early return of bowel function and hospital discharge compared with similar patients managed off protocol.

STUDY DESIGN

To test this hypothesis, we performed a case-controlled study comparing the hospital courses of 36 study patients to 36 control patients undergoing colorectal surgery by the same surgeons during the same calendar year. The distribution of types of operations and anesthetic techniques was similar in both groups.

RESULTS

As dictated by the protocol, all study patients had their nasogastric tubes removed, were started on a low fat liquid diet, and ambulated in the first postoperative day. Nasogastric tubes were removed in control patients and study patients 2.2 +/- 0.9 (mean value +/- SD) and 1.0 +/- 0.0 days postoperatively, respectively. Control patients were started on an oral diet, usually clear liquids, an average of 2.9 +/- 1.1 days postoperatively, a specific liquid diet was started 1.0 day postoperatively in study patients (p < 0.001). Return of bowel function, as determined by bowel tones, flatus, and bowel movements, occurred approximately 1 day earlier in study patients. Study patients were discharged 1 day sooner than control patients.

CONCLUSIONS

Our results suggest that the return of bowel function and the length of stay of patients undergoing colon surgery are improved if patients are entered into a standardized protocol that eliminates variation in intraoperative and postoperative anesthesia and postoperative surgical care. We believe these results can be reproduced in routine clinical surgery by having a clearly outlined protocol for perioperative care similar to that used in this study.

The effect of epinephrine on small-dose hyperbaric bupivacaine spinal anesthesia: clinical implications for ambulatory surgery

The effect of adding epinephrine to small doses of spinal bupivacaine on the duration of sensory motor block has not been carefully investigated. Twelve volunteers underwent hyperbaric bupivacaine spinal anesthesia (7.5 mg) with and without epinephrine (0.2 mg) in a randomized, double-blind, cross-over fashion. Sensory block was assessed with pinprick, transcutaneous electrical stimulation (TES) equivalent to surgical stimulation (at umbilicus, pubis, knee, and ankle), and tolerance of a pneumatic thigh tourniquet. Motor block was assessed with isometric force dynamometry. Discharge criteria were defined as return of pinprick sensation to dermatome S2, ability to ambulate, and ability to urinate. Extent of sensory block to pinprick over time was unaffected by the addition of epinephrine. However, epinephrine prolonged tolerance of TES at the pubis, knee, and ankle (33-48 min, P < 0.05) and of thigh tourniquet (30 min, P < 0.01). Motor block was prolonged by epinephrine at the quadriceps and gastrocnemius muscles (by 23 and 51 min, respectively, P < 0.002). Achievement of discharge criteria was prolonged by 48 min by the addition of epinephrine (P < 0.01). Thus, epinephrine may prolong surgical anesthesia for lower abdominal and lower extremity surgery and delay time until patients achieve discharge criteria.

IMPLICATIONS

Using a cross-over study design, 12 volunteers underwent bupivacaine spinal anesthesia with and without epinephrine. This study suggests that adding epinephrine to bupivacaine may prolong surgical anesthesia and also delay patients' discharge.

Patient-controlled epidural analgesia with bupivacaine and fentanyl on hospital wards: prospective experience with 1,030 surgical patients

BACKGROUND

The efficacy and safety of patient-controlled epidural analgesia (PCEA) for postoperative analgesia on hospital wards was studied.

METHODS

Postoperative analgesia was provided for 1,030 patients with PCEA using 0.05% bupivacaine and fentanyl, 4 microg/ml, in a standardized manner. Patients were seen at least twice a day by the staff of the anesthesia pain management service. Prospectively gathered data included verbal pain scores at rest and activity (0-10); consumption of bupivacaine and fentanyl; and incidences of pruritus, nausea, sedation, hypotension, motor block, and respiratory depression. Descriptive statistics were used. Risk factors for side effects were determined using logistic regression.

RESULTS

The study included 552 women and 477 men who underwent a median (mode) of 3 (2) days of PCEA. Their mean age was 59 +/- 16 yr and their mean weight was 76 +/- 19 kg. There were 454 abdominal, 165 gynecologic, 126 urologic, 108 vascular, 90 thoracic, 83 orthopedic, and 4 plastic surgical procedures. Median (mode) pain scores were 1 (0) at rest and 4 (5) with activity on postoperative day 1. Incidences of side effects were 16.7% (pruritus), 14.8% (nausea), 13.2% (sedation), 6.8% (hypotension), 2% (motor block), and 0.3% (respiratory depression). Reasons for termination of PCEA were elective (82%), displaced epidural catheter (12%), anticoagulation (3%), infection (1%), side effects (1%), inadequate analgesia (1%), and other (<1%). Risk factors for side effects were female sex, patient weight <73 kg, patient age <58 yr, bupivacaine and fentanyl consumption >9 ml/h, use of analgesic adjuncts, and lumbar placement of epidural catheters.

CONCLUSION

Patient-controlled epidural analgesia provides effective and safe postoperative analgesia on hospital wards.