Evaluation of collimated polarized light imaging for real-time intraoperative selective nerve identification in the human hand.

Intraoperative peripheral nerve lesions are common complications due to misidentification and limitations of surgical nerve identification. This study validates a real-time non-invasive intraoperative method of nerve identification. Long working distance collimated polarized light imaging (CPLi) was used to identify peripheral radial nerve branches in a human cadaver hand by their nerve specific anisotropic optical reflection. Seven ex situ and six in situ samples were examined for nerves, resulting after histological validation, in a 100% positive correct score (CPLi) versus 77% (surgeon). Nerves were visible during a clinical in vivo observation using CPLi. Therefore CPLi is a promising technique for intraoperative nerve identification.

Glutamate-like immunoreactivity during hair cell recovery after gentamicin exposure in the chinchilla vestibular sensory periphery.

OBJECTIVE: Determine the expression of glutamate by immunohistochemistry in normal and recovering vestibular hair cells in the chinchilla crista ampullaris after gentamicin ototoxicity. STUDY DESIGN: In five groups of three animals each, ototoxicity was produced by placing gentamicin (50 microg)-impregnated Gelfoam pellets within the perilymphatic space of the superior semicircular canal. Animals were sacrificed at 1, 2, 4, 8, and 16 weeks after treatment. A group of normal (n=3) animals was also processed. METHODS: For the detection of glutamate the inner ears of these animals were dissected, and the horizontal cristae ampullaris embedded in plastic. Two-micron-thick tissue sections were obtained and incubated with monoclonal antibodies against glutamate. The immunoreaction was detected using the avidinbiotinylated-complex technique and diaminobenzidine was the chromogen. RESULTS: Normal sensory epithelia demonstrated type I and type II hair cells with moderate glutamate-like immunoreactivity. Supporting cells demonstrated no glutamate-like immunoreactivity. Afferent nerve fibers and calyxes surrounding type I hair cells demonstrated strong glutamate-like immunoreactivity. At 1 and 2 weeks after treatment the few type II hair cells surviving ototoxic treatment (15%-18%) contained moderate glutamate-like immunoreactivity, supporting cells showed no immunoreactivity, and nerve terminals and fibers displayed strong immunoreactivity. At 4 and 8 weeks after treatment, recovered hair cells (80%) had greater glutamate-like immunoreactivity when compared with normal hair cells, supporting cells displayed no glutamate-like immunoreactivity, and afferent fibers contained strong glutamate-like immunoreactivity. At 16 weeks, glutamate-like immunoreactivity in hair cells returned to normal level. CONCLUSION: Glutamate may be used as an indicator of hair cell differentiation and as an index of the molecular recovery of hair cells after ototoxicity.

Spontaneous cervical hemorrhage with near-complete airway obstruction.

BACKGROUND: Retropharyngeal hematoma is a rare entity which may progress rapidly to airway obstruction. Previously documented causes have included coagulopathic states, trauma, infection, parathyroid adenoma rupture, and foreign-object ingestion. Four cases of spontaneous retropharyngeal hematomas without any known predisposing risk factors have been previously reported. Two of these cases had fatal outcomes. METHODS: A case report is presented and the literature reviewed. RESULTS: Spontaneous cervical hematoma with parapharyngeal and retropharyngeal involvement which caused near-complete respiratory obstruction occurred in an otherwise healthy young man following straining. Initial management involved fiberoptic nasotracheal intubation. Subsequent right neck exploration revealed hemorrhage from a branch of the external carotid artery, which was ligated. An arteriogram revealed minimal flow through the right external carotid artery and its branches. The patient was extubated and discharged uneventfully on the fourth postoperative day. CONCLUSION: The possible etiology for this case is discussed, and a review of the literature and the role of surgery in the management of this entity is outlined.

Characterization of lymphocyte subpopulations in Warthin's tumor.

Cell suspensions from six Warthin's tumors (WTs) were characterized with fluorescence-labeled cell cytometry. WT lymphocyte subsets were identified with monoclonal antibodies directed against lymphocyte-associated cell antigens including T lymphocyte subsets, B lymphocytes, and natural killer (NK) cells. Results showed that T cell proportions were 58% and B cell proportions were 39%. The T cell helper:cytotoxic-suppressor ratio was 5.7:1 and the B to T cell ratio was 0.8:1. NK cells represented 1.3% of cells. When compared to peripheral blood lymphocytes (PBLs) in the same patients, statistically significant differences were noted between PBLs and WT lymphocytes in the percentage of B lymphocytes (P < .01), T cytotoxic-suppressor lymphocytes (P < .02), NK cells (P < .01), and in the ratios of B to T lymphocytes (P < .01) and T helper to T cytotoxic-suppressor lymphocytes (P < .03). Comparing these data to retrospective data on lymphocyte distribution in normal and reactive lymph nodes, the epithelial component does not appear to exert a local effect on the lymphoid component of WT.

Case of pulmonary alveolar proteinosis treated by sequential whole-lung lavages and a review of the condition.

We report our first local case of pulmonary alveolar proteinosis that required symptomatic therapy with whole lung lavage. This is a rare condition associated with the accumulation of phospholipid material in the alveoli. The presentation is usually insidious and the symptomatology varies from vague complaints to severe crippling dyspnoea. The diagnosis is often delayed and usually made after the exclusion of other conditions. While there is no definitive treatment apart from lung transplant, whole-lung lavage is a safe, repeatable procedure which offers the best prospect for symptomatic, physiological and radiological improvement in severe cases.

The experience of two-epidural-catheter for painless labor.

'Two epidural-catheters' method was used to relieve labor pain during the first and second stage of labor course. Six milliliters of a mixture of '0.15% bupivacaine +0.03% xylocaine +0.0005% fentanyl' was the main agent given through the epidural catheter every 2 hours when the cervix was 3-4 cm dilated with 4 ml of 1% xylocaine as test dose. Addition doses of the mixture were given when needed. Fifty two, ASA I-II, parturients (primigravida: 43, multipara: 9) were included in this study. The mode of delivery was: 59.6% by vacuum, 36.4% by normal spontaneous delivery (NSD), and 4% by Cesarean Section (C/S). 88.5% of newborns had Apgar score > or = 7 at 1 minute and all had Apgar score > or = 7 at 5 minutes. 38(73%) of 52 parturients were fully satisfied with the analgesic effect during the whole labor course and 14(27%) of 52 parturients were partially satisfied with the analgesic effect owing to 1) intolerable lower abdominal pain (11 cases), 2) mild painful episiotomy (1 case), and backache (2 cases). No motor block was noted. Good analgesic effect during the second stage labor course could be obtained by our 'Two-Epidural-Catheter' method and no significant complications of newborns and parturients were noted in our study.

Spread of spinal anaesthesia with 0.5% bupivacaine: influence of the vertebral interspace and speed of injection.

Three millilitres of plain 0.5% bupivacaine were injected intrathecally at two different spinal interspaces (L2/3 and L4/5) and at two different speeds (15 and 30 sec) in four groups of ten patients. Injection at L2/3 over 15 sec produced a significantly higher mean maximum spread of analgesia (T6.4) when compared to injection at L4-5 over 15 sec (T10.3) (P < 0.05). Over the same interspace L2/3, injection over 15 sec also produced a higher level of spread as compared to the 30 sec group (p < 0.05). At 15 min there was a greater fall in blood pressure in the L2/3 15 sec group when compared to the other groups (p < 0.01). There was a further decrease in the blood pressure in L2/3 15 sec and L4/5 30 sec groups after 30 minutes of blockade (p < 0.01). Therefore close monitoring of cardiovascular parameters must be continued for at least 30 min in spinal anaesthesia with bupivacaine.

Phenylephrine eye drops in ophthalmic surgery--a clinical study on cardiovascular effects.

Phenylephrine in concentrations of either 2.5% or 10% is widely used as a mydriatic agent in ophthalmic surgery. Its potential cardiovascular effects are seldom recorded as ophthalmic surgery is not usually monitored by an anaesthetist. A prospective randomised double blind study was carried out in 89 consecutive cases of uncomplicated cataract surgery in the presence of an anaesthesiologist ensuring the continuous monitoring of blood pressure, heart rate, electrocardiography and pulse oximetry. All these patients were given a drop of either normal saline, 2.5% or 10% phenylephrine in addition to mydriacyl prior to surgery. Blood pressure readings were found to be significantly higher in non-hypertensive patients receiving phenylephrine at the start of the operation and at five, 10, 15 and 20 minutes intra-operatively and the first three hours post-operatively. Blood pressure readings in hypertensive patients, on the other hand, were also found to increase after phenylephrine administration, though not statistically significant. 10.3% of the 10% phenylephrine group and 3% of the 2.5% phenylephrine group required intraoperative intravenous hypotensive agent to control the blood pressure. There were no arrhythmias or ischaemic changes observed intraoperatively. None of the patients complained of palpitation, headache or chest discomfort. There was no oxygen desaturation observed. We concluded that significant hypertensive effects can arise after phenylephrine eye drop administration. Hence, it should be used cautiously with intraoperative monitoring of the cardiovascular status during cataract surgery.

Sedation for gastroscopy: a comparison between midazolam and midazolam with nalbuphine.

Forty patients received either midazolam or midazolam with nalbuphine in a double-blind randomised study of sedation for upper gastrointestinal endoscopy. There were less retching, gagging and salivation in the combination group compared to midazolam alone. They were also more cooperative. These resulted in greater ease of insertion of the gastroscope. There was no significant difference in the degree of amnesia in both groups. A significant decrease in oxygen saturation was noted in both groups during the procedure. Monitoring with a pulse oximeter is recommended when sedation is administered during gastroscopy.

Mast cells are not essential to inflammation in murine model of colitis.

A simple rat model of chronic intestinal inflammation was adapted to mice in order to ascertain whether mast cells play an essential role in its induction or perpetuation. Colitis was induced in C57BL mice by intrarectal administration of trinitrobenzene sulfonic acid in 50% ethanol. Higher doses of trinitrobenzene sulfonic acid per gram of body weight were required in mice than rats, with a narrower effective dose range (the upper dose limited by unacceptable mortality and the lower by decreased inflammation). Colons of treated mice were macroscopically inflamed, with transmural damage, adhesions to adjacent structures, and ulcerations. Inflammation was scored subjectively and by tissue weight and myeloperoxidase content; each index was increased dose-dependently by trinitrobenzene sulfonic acid doses of 0.3-10 mg. Six milligrams of trinitrobenzene sulfonic acid induced reproducible inflammation for up to four weeks. Trinitrobenzene sulfonic acid could induce inflammation in both mast-cell-deficient W/Wv mice and their normal +/+ littermates in a similar fashion. Thus it is possible to induce chronic colitis in the mouse. Mast cells are not essential participants in this process.

The histamine content of oriental foods.

Several of the symptoms of scombroid poisoning (i.e. histamine toxicity) resemble those observed in people suffering from Chinese restaurant syndrome. Therefore, the histamine content of representative Chinese cuisine, which included 31 common dishes, 12 condiments and 12 basic ingredients from several sources, was measured using a sensitive and specific radioenzymatic assay. A further enzymatic procedure involving diamine oxidase was used to verify that the substance measured was histamine. A total of 184 assays were performed on 57 samples in the study. High levels of histamine were found in the cheeses, which were used as positive controls (863.6 micrograms histamine/g blue cheese and 107.4 micrograms histamine/g Parmesan cheese), and in some common condiments, including tamari (2392.2 micrograms histamine/g sample) and one brand of soy sauce (220.4 micrograms histamine/g sample). The histamine content of four condiments and three common dishes was over 10 micrograms histamine/g sample, while four condiments and 16 common dishes contained less than 1 microgram histamine/g sample. Calculations involving representative amounts of food that can be consumed at a typical oriental meal suggest that, in some cases, histamine intake may approach toxic levels. The results are discussed with regard to the possible role of histamine in reactions associated with restaurant meals.

Asynergy of right ventricular wall motion in man.

Canine studies have shown a correlation between instantaneous segmental lengths in the right ventricular free wall and chamber volume, pressure, and stroke work. To determine whether such correlations exist in intact man, we studied the temporal relationships between chord dynamics in various regions of the right ventricle in 21 heart transplant recipients with apparently normal right ventricular function. Patients were examined by biplane radiography while performing various maneuvers (e.g., Valsalva maneuver). Computer-aided analysis of biplane radiograms of five surgically inserted radiopaque tantalum right ventricular myocardial markers was used to calculate interpoint chord lengths at 33 msec sampling intervals. Two patterns of right ventricular chord asynergy were defined: (1) An akinetic chord had an amplitude of less than 2.0 mm during the course of at least one beat; (2) an out-of-phase chord was more than a quarter period out of phase from the average curve (derived from all concurrently measured marker pairs during each maneuver) for at least one beat. Considering all chords (n = 978), 60 chords (6.1%) were akinetic and nine chords (0.9%) were out of phase. Excluding the outflow tract markers (n = 581), 33 chords (5.7%) were akinetic and five chords (0.9%) showed out-of-phase movement. During some maneuver, at least one akinetic chord occurred in 57% of patients and out-of-phase chords in 33% of patients. Most right ventricular regions were implicated in asynergic motion, including the right ventricular free wall, acute margin, and outflow tract. The frequency and distribution of asynergy in right ventricular chord dynamics observed in this study suggests that changes in a single right ventricular dimension may not accurately reflect global right ventricular events.