Reliability of the pre-operative imaging to assess neck nodal involvement in oral cancer patients, a single-center study.

BACKGROUND: Primary sites for the metastasis of oral cancer are the cervical lymph nodes. Although there has been considerable technical advancement in the radiological imaging, capability to recognize all metastatic lymph nodes pre-operatively has remained as a challenge. Thus elective neck dissection (END) has remained as reliable practice to treat cervical lymph nodes. This study evaluated the accuracy of pre-operative imaging in pre-operative diagnostics of cervical lymph node status using computed tomography or magnetic resonance imaging in patients with oral squamous cell carcinoma (OSCC). We have also considered the reasons for the difficulties to recognise metastatic nodes in cervical area. MATERIAL AND METHODS: Patient charts of patients who had had elective neck dissection as a treatment for primary OSCC in the Department of Oral and Maxillofacial Surgery, Helsinki University Hospital between 2016 and 2017 were assessed retrospectively. The outcome variable was post-operatively histologically confirmed lymph node metastasis in the neck area. The primary predictor variable was radiologically confirmed metastasis in the neck area. The explanatory variables were age, sex, pT-class, imaging modality, delay and location of the tumour. Descriptive statistics, sensitivity, specificity and Youden-J index were computed. RESULTS: Eighty-three patients were included in the study. The sensitivity to detect pathological lymph nodes was 44.8%, and the specificity for the examination was 87.0%. 19.3% of cN0 patients had metastasis in the cervical nodes, whereas of the cN+ patients 8.4% were actually pN0. Patients having cN0, the largest neck metastasis was over 10 mm in 12.5%, whereas cN1-3 patients the corresponding rate was 45.5%. The computational threshold to diagnose a metastatic node was 7 mm. CONCLUSIONS: Especially small metastases are difficult to diagnose. Limitations of radiological diagnostics must be considered when treating OSCC.

Interactions between extraradical ectomycorrhizal mycelia, microbes associated with the mycelia and growth rate of Norway spruce (Picea abies) clones.

Despite their ecological relevance, field studies of the extraradical mycelia of ectomycorrhizal (ECM) fungi are rare. Here we examined in situ interactions between ECM mycelia and host vigour. Ectomycorrhizal mycelia were harvested with in-growth mesh bags buried under Norway spruce (Picea abies) clones planted in 1994 in a randomized block design. Mycelial biomass was determined and fungal species were identified by denaturing gradient gel electrophoresis (DGGE) and sequencing of the internal transcribed spacer 1 (ITS1) region. Microbial community structure in the mycelium was investigated by phospholipid fatty acid (PLFA) profiling. Compared to slow-growing spruce clones, fast-growing clones tended to support denser mycelia where the relative proportions of Atheliaceae fungi and PLFAs indicative of Gram-positive bacteria were higher. Ascomycetes and PLFAs representative of Gram-negative bacteria were more common with slow-growing clones. In general, the ECM mycelial community was similar to the ECM root-tip community. Growth rate of the hosts, the ECM mycelial community and the microbes associated with the mycelium were related, suggesting multitrophic interactions between trees, fungi and bacteria.

Ectomycorrhizal community structure varies among Norway spruce (Picea abies) clones.

In northern boreal forests, the diversity of ectomycorrhizal (ECM) species is much greater than that of their host trees. This field study investigated the role of individual trees in shaping the ECM community. We compared ECM communities of eight Norway spruce (Picea abies) clones planted in a clear-cut area in 1994 with a randomized block design. In 2003, the ECM fungi were identified from randomly sampled root tips using denaturing gradient gel electrophoresis (DGGE) and rDNA internal transcribed spacer (ITS) sequence similarity. ECM diversity varied among clone groups, showing twofold growth differences. Moreover, according to detrended correspondence analysis (DCA), ECM community structure varied not only among but also within slow-growing or fast-growing clones. Results suggest that ECM diversity and community structure are related to the growth rate or size of the host. A direct or indirect influence of host genotype was also observed, and we therefore suggest that individual trees are partly responsible for the high diversity and patchy distribution of ECM communities in boreal forests.

Comparison of the effects of clozapine, chlorpromazine, and haloperidol on membrane lateral heterogeneity.

The interactions of three neuroleptic drugs, clozapine (CLZ), chlorpromazine (CPZ), and haloperidol (HPD) with phospholipids were compared using DSC and Langmuir balance. Main emphasis was on the drug-induced effects on the lateral organization of lipid mixtures of the saturated zwitterionic 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) and the unsaturated acidic phosphatidylserine, brainPS. In multilamellar vesicles (MLV) phase separation was observed by DSC at X(PS)> or =0.05. All three drugs bound to these MLVs, abolishing the pretransition at X(drug)> or =0.03. The main transition temperature (T(m)) decreased almost linearly with increasing contents of the drugs, CLZ having the smallest effect. In distinction from the other two drugs, CLZ abolished the phase separation evident in the endotherms for DPPC/brainPS (X(PS)=0.05) MLVs. Compression isotherms of DPPC/brainPS/drug (X(PS)=X(drug)=0.05) monolayers revealed the neuroleptics to increase the average area/molecule, CLZ being the most effective. Penetration into brainPS monolayers showed strong interactions between the three drugs and this acidic phospholipid (in decreasing order CPZ>HPD>CLZ). Hydrophobic interactions demonstrated using neutral eggPC monolayers decreased in a different order, CLZ>CPZ>HPD. Fluorescence microscopy revealed domain morphology of DPPC/brainPS monolayers to be modulated by these drugs, increasing the gel-fluid domain boundary length in the phase coexistence region. To conclude, our data support the view that membrane-partitioning drugs could exert part of their effects by changing the lateral organization and thus also the functions of biomembranes.

Difficult airway in a patient with Marshall-Smith syndrome.

Marshall-Smith syndrome is a rare clinical disorder characterized by accelerated bone maturation, dysmorphic facial features, airway abnormalities and death in early infancy because of respiratory complications. Although patients with Marshall-Smith syndrome have several features with potential anaesthetic problems, previous reports about anaesthetic management of these patients do not exist. We present a case, in which severe hypoxia developed rapidly after routine anaesthesia induction in an eight-month-old male infant with this syndrome. After several unsuccessful attempts the airway was finally secured by blind oral intubation. After 2 weeks, laryngeal anatomy was examined with fibreoptic laryngoscopy which revealed significant laryngomalacia. Laryngoscopy was performed without problems with ketamine anaesthesia and spontaneous breathing. The possibility of a compromised airway should always be borne in mind when anaesthetizing patients with Marshall-Smith syndrome. Anaesthesia maintaining spontaneous breathing is safest for children with this syndrome. If tracheal intubation or muscle relaxation is required, precautions are needed to maintain a patent airway. Muscle relaxants should possibly be avoided before intubation.

Hypotensive anesthesia for middle ear surgery: a comparison of propofol infusion and isoflurane.

An infusion of propofol (2,6-diisopropylphenol) was compared with isoflurane to induce hypotension for middle ear surgery. Forty patients (ASA physical status I-II, 16-55 years) scheduled for elective surgery were included in an open randomized study. The pharmacokinetics of propofol infusion were also studied in 6 patients. Both agents produced controlled hypotension (MAP reduction of 30% from the baseline values) with an acceptable visibility of the surgical field. No major complications occurred. The mean total dose of propofol infusion was 6.4 +/- 2.7 mg/kg and the mean concentration of isoflurane was 0.9 +/- 0.4%. Considerable interindividual pharmacokinetic variability was found and propofol was extensively distributed and rapidly cleared from the body after the infusion. Propofol infusion may be a new alternative as a hypotensive agent in middle ear surgery.

Individual alcohol reaction profiles.

The purpose of this study was to evaluate interindividual variation in acute reactions to ethanol. Six young, healthy female subjects participated in a double-blind experiment consisting of two identical alcohol sessions and one control session where glucose was infused instead of ethanol. Alcohol was infused in a standardized way to reach blood alcohol concentration of 1 mg/ml in 1 hr. During the 4 hr-sessions EEG-spectra, smooth pursuit eye movements, various mood variables, BAC and breath alcohol concentrations were studied repeatedly. The results showed that the subjects had a rather repeatable, individual reaction profile as expressed by changes in alpha mean frequency, theta band power, amount of corrective eye movements and subjective intoxication. The sensitivity of the subject to ethanol should thus be expressed as a reaction profile rather than as a change in a single variable.

Acute effects of intravenously given alcohol on saccadic eye movements and subjective evaluations of intoxication.

Effects of intravenously given alcohol on eye movements were analysed in ten voluntary subjects. Each subject served as his/her own control. Good correlations were found between the changes in saccade variables and subjective evaluations of alertness, eye movement control and intoxication. Interindividually, the subjective evaluation of drunkenness correlates with the alcohol effect on saccade variables better than do the other subjective variables or blood or breath alcohol concentrations. A steady decrease of mean and maximum velocity and a steady increase in the duration of saccades was observed during the alcohol infusion. The latency of saccades also increased. There was, however, a slight decrease of latency due to alcohol 15 min after the start of infusion, suggesting a biphasic effect of alcohol on saccade latency.

A pharmacokinetic and pharmacodynamic study of flunitrazepam.

Flunitrazepam was given as an induction agent i.v. to 12 patients undergoing otologic operations. Pharmacokinetics were evaluated from serum samples at 5 min-72 h by 63Ni-EC-GLC. Pharmacodynamic characteristics were estimated subjectively by simple questionnaire and objectively by the anesthetist during and after anesthesia. The dose of flunitrazepam required for anesthesia varied from 14 to 33 (mean 21) micrograms/kg and was not related to age. The mean distribution volumes of flunitrazepam, calculated by the three-compartment open model, were Vd1 0.61 (SD = 0.36) l/kg, Vd2 1.4 (SD = 0.70) l/kg, and Vd3 3.6 (SD = 1.39) l/kg. The mean elimination half-life was 25 h and serum clearance was 94 ml/min. The maximum decreases in blood pressure during anesthesia correlated with the age of the patients. The general assessment of the anesthetist about this form of anesthesia was positive in 75% of the 12 cases. A clear anterograde amnesia was found.

Hemodynamic effects of labetalol in healthy volunteers.

The hemodynamic effects of intravenous injection of 1 mg/kg of labetalol were measured in eight healthy volunteers, using impedance cardiography and systolic time intervals. The mean systolic blood pressure was reduced by 10% (p less than 0.01) and diastolic by 6% (p less than 0.05) 30 min after the injection, and they had returned to pre-drug level 2 h after administration. Heart rate declined consistently throughout the observation period. Cardiac index was reduced by 16% (p less than 0.05), but the changes in stroke volume (- 6%) and peripheral resistance (+ 23%) were not statistically significant. Left ventricular ejection time index increased by 2% (p less than 0.05), and nonsignificant changes were found for pre-ejection period index (- 3%), total electromechanical time index (+ 1%), and PEP/LVET ratio (+ 5%). In healthy subjects resting supine the intravenous dose of 1 mg/kg of labetalol had predominantly beta-blocking effects.

Comparison of midazolam and flunitrazepam for night sedation. A randomised double-blind study.

In a double-blind randomized study midazolam 15 mg and flunitrazepam 2 mg caused a significantly better night's sleep than placebo. Midazolam had a moderate sedative effect the following morning but, in other respects studied, no residual effects were found. In contrast, flunitrazepam decreased both the degree of apprehension and excitement the following morning. Flunitrazepam also inhibited salivary secretion and caused less cardiovascular changes than placebo or midazolam. The dose of thiopentone needed for induction of anaesthesia was significantly lower in those given flunitrazepam. The results show that midazolam is a potent sedative agent with a short duration of action.

Effect of age and cardiopulmonary bypass on the pharmacokinetics of lorazepam.

The pharmacokinetics of lorazepam after 0.03 mg/kg intravenous administration was investigated in 14 surgical patients (nasal surgery under local anaesthesia) ranging in age from 25 to 86 years (8 males and 6 females). No statistically significant changes in the kinetics of lorazepam associated with the aging process were found. In these premedicated patients a slow onset of the drug action of lorazepam was assessed both subjectively and objectively with no apparent relationship to the age. These findings are of potential clinical importance, because it is highly desirable to use drugs for which age-related alterations are of minimum degree. In 5 male patients undergoing surgery with cardiopulmonary bypass, lorazepam disappeared from the plasma after a single 4 mg intravenous injection with an apparent comparable half-life (10.0 +/- 3.2 min.) to that of the above mentioned surgical patients. The concentrations of both unconjugated and conjugated lorazepam dropped abruptly at the start of extracorporeal circulation followed by an increase in the postperfusion period. After this peak effect the mean apparent half-life of lorazepam was 15.5 +/- 5.8 hours of indicating no great change in its elimination in comparison with patients operated under local anaesthesia (half-life 12.1 +/- 3.7 hours). Pharmacokinetically, lorazepam appears to be a useful agent in connection with cardiopulmonary bypass operation.

Comparison of old and new types of premedications.

By random allocation 41 patients received 1 mg flunitrazepam orally the night before operation and 1 mg on the morning of operation (group 1), and another 41 received 100 mg pentobarbital orally the night before operation, followed by intramuscular scopolamine (0.006 mg/kg) + morphine (0.02 mg/kg) on the morning of operation (group 2). All patients received 0.5 mg atropine intravenously just before the induction of anesthesia. The patients in group 2 were better sedated and had less salivary secretion than those in group 1, but otherwise both were comparable. In group 2 the induction requirements of thiopentone were significantly decreased in comparison with group 1, again indicating a more potent sedative effect. Because even in the total scoring of the results there was no significant difference between the two groups, the easy oral route of administration of flunitrazepam offers a clinically relevant alternative to the conventional premedication. In some of these E.N.T. patients who received flunitrazepam, intravenous atropine given just before the induction of anesthesia was unable to prevent salivary secretion. Oral benzodiazepine derivatives (flunitrazepam) appear to be useful before surgery as the old type of premedication (oral pentobarbital + i.m. scopolamine and morphine).

Midazolam compared with thiopentone as an induction agent.

In patients premedicated with scopolamine + morphine (+5 mg nitrazepam the evening before surgery), the sleep-inducing effect of midazolam 0.15 mg/kg i.v. was clearly slower in onset than that of thiopentone 4.67 mg/kg i.v. Somewhat fewer cardiovascular and local sequelae were found in the midazolam group, but, although apnoea occurred less often in the midazolam group it lasted longer. On the whole, the differences between midazolam and thiopentone had no apparent clinical consequences. Midazolam is a new alternative agent for induction in combination anaesthesia.

A comparative study on the clinical effects of flunitrazepam and oxazepam as oral premedication.

The clinical effects of flunitrazepam and oxazepam as oral premedicants were tested in a double-blind study of 69 otorhinolaryngologic patients. Flunitrazepam had a somewhat higher sedative effect (p less than 0.10) and moderated the increase in systolic blood pressure significantly (p less than 0.005) more than did oxazepam, but as regards the other parameters tested no significant differences were found (sleep, apprehension, excitement, dizziness, emetic effect, headache, increase in heart rate, venepuncture). In some patients a profuse salivary secretion was observed despite intravenous injection of atropine just before the induction of anesthesia. Our results support earlier claims of flunitrazepam's relatively strong sedative and anxiolytic properties, but on the whole the difference in clinical effects of these benzodiazepine derivatives was not marked.