PubMed Health⌕ Search

Biomedical subjects

A Grippo

Publications and source records attributed to A Grippo.

At least 19 recordsLinked to original sources
PubMed2006

Continuous EEG-SEP monitoring of severely brain injured patients in NICU: methods and feasibility.

AIMS: To evaluate the feasibility of a continuous neurophysiologic monitoring (electroencephalography (EEG)-somatosensory evoked potentials (SEPs)) in the neuro-intensive care unit (NICU), taking into account both the technical and medical aspects that are specific of this environment. METHODS: We used an extension of the recording software that is routinely used in our unit of clinical neurophysiology. It performs cycles of alternate EEG and SEP recordings. Raw traces and trends are simultaneously displayed. Patient head and stimulator box are placed behind the bed and linked to the ICU monitoring terminal through optic fibers. The NICU staff has been trained to note directly clinical events, main artefacts and therapeutic changes. The hospital local area network (LAN) enables remote monitoring survey. RESULTS: Continuous EEG (CEEG)-SEP monitoring was performed in 44 patients. Problems of needle detachment were seldomly encountered, thanks to the use of a sterile plastic dressing, which covers needles. We never had infection or skin lesions due to needles or the electrical stimulator. The frequent administration of sedative at high doses prevented us from having a clinically valuable EEG in several cases but SEPs were always monitorable, independently of the level of EEG suppression. The diagnosis of seizures and non-epileptic status was based on raw EEG, while quantitative EEG (QEEG) was used to quantify ictal activity as a guide to treatment. CONCLUSIONS: EEG and EP waveforms collected in NICU were of comparable quality to routine clinical measurements and contained the same clinical information. A continuous SEP monitoring in a comatose and sedated patient in NICU is not technically more difficult and potentially less useful than in operating room. This monitoring appears to be feasible provided the observance of some requirement regarding setting, electrodes, montages, personnel integration, consulting and software.

Brain Injuries↗
PubMed2006

Carpal tunnel syndrome and ulnar neuropathy at the elbow in floor cleaners.

OBJECTIVE: To determine the occurrence of carpal tunnel syndrome (CTS) and ulnar neuropathy at the elbow (UNE) in a cohort of floor cleaners and to check differences between workers with and without CTS. METHODS: All female floor cleaners of three major hospitals in Tuscany (Italy) were contacted. Clinical and electrophysiological severity of CTS and UNE were evaluated with standardized scales and symptoms were assessed with the self-administered Boston Questionnaire (BQ); demographic and non-occupational factors and durations of current and previous occupations were recorded. Univariate analysis of risk factors was performed in workers with and without CTS. Logistic regression was used to evaluate the capacity of independent variables to predict CTS. RESULTS: Out of a total of 179 cleaners, 145 (81%)-mean age 39.6 years (20-64 years)-were enrolled in the study; 70 (48%) had CTS (diagnosis based on clinical and electrophysiological findings). BQ symptom and hand function scores were anomalous in 108 (74%) and 84 (58%) subjects, respectively. UNE was detected in 7/103 women. Univariate analysis showed that cleaners with CTS were older, had greater BMI and longer exposure to cleaning with previous employers than those without CTS. In the logistic regression, the only predictor of CTS was cleaning with previous employers (O.R. 12.1, 95% CI 3-49.9). CONCLUSIONS: These results indicate a high occurrence of CTS in floor cleaners; UNE is less frequent than CTS, presumably due to repetitive movements that stress wrists more than elbows. The only predictive factor of CTS was cleaning as an occupation with previous employers. Therefore, the actual risk factor for CTS could not be cleaning per se, but how this job is performed.

Adult↗
PubMed2004

Anoxic-ischemic alpha coma: prognostic significance of the incomplete variant.

The prognostic significance of post-anoxic-ischemic alpha coma (AC) is controversial. We recorded somatosensory evoked potentials (SEPs) and performed serial electroencephalography (EEG) in a 60-year-old woman in coma after cardiac arrest. The first EEG was recorded after 48 hours (GCS=5; E1-V1-M3); brain-stem reflexes were preserved. The EEG pattern showed monotonous alpha frequencies (10-11 Hz) with posterior predominance; acoustic and noxious stimuli evoked EEG reactivity. Early cortical SEPs (72 h) were normal. On the fifth day (GCS=8; E4-V1-M3), the EEG alpha pattern was replaced by a diffuse delta activity; rhythmic theta changes appeared spontaneously or in response to stimuli. The patient regained consciousness on the tenth day and EEG showed posterior theta activity (6-7 c/s) partially reactive to stimuli. At the 6-month follow-up, cognitive evaluation showed mild dementia. Recent studies identified two forms of AC. Patients with complete AC have an outcome that is almost invariably poor. Conversely, incomplete AC (posteriorly accentuated alpha frequency, reactive and with SEPs mostly normal) reflects a less severe degree of anoxic-ischemic encephalopathy. The case we report should be classified, according to the SEPs and EEG features, as incomplete AC. The fact that the patient has regained consciousness, even if with residual cognitive impairment, confirms the need to distinguish this variant from complete AC.

Alpha Rhythm↗
PubMed2003

Respiratory-related evoked potential and upper airway transmural pressure change by using the negative expiratory pressure (NEP) device.

OBJECTIVE: Several studies have previously shown respiratory related evoked potentials (RREP) in humans elicited by mechanical stimuli applied on upper airways (UA). According to us, heterogeneous findings, concerning latencies and amplitudes, have been reported because of the different timing of stimuli application during the respiratory cycle and/or features of pressure stimuli. Therefore we evaluated the cortical response evoked by transmural pressure changes at the mouth induced by a negative expiratory pressure (NEP) device. METHODS: RREP were recorded in 22 healthy non-obese, non-snoring volunteers. The subjects were studied awake in seated position during quiet breathing. Three different pressure levels were applied, in a random order, 200 ms after the beginning of expiration. Cortical electrical responses were recorded from scalp electrodes at Fz, Cz, and Pz scalp location (international 10-20 system) referenced to the linked earlobes. RESULTS: RREP responses consisted of two negative (N45, N120) and two positive (P22, P85) waves. There was no significant effect of pressure or electrode on component latencies. The P22 wave (PRESSURE: F(df 2,42)=6.66, P<0.01), the N45 wave (PRESSURE: F(df 2,42)=16.51, P<0.001), and the P85 wave (PRESSURE: F(df2,42)=15.15, P<0.001) increased significantly theyr amplitude with increasing from pressure stimuli 1 to 10 cmH2O. CONCLUSIONS: The present results suggest that the UA NEP application in humans is a reliable way of evoking cortical responses. The experimental features that we described allow us to minimize the confounding factors in evaluating RREPs. The NEP device appears to be a useful tool for investigation of the neurobiology of UA sensation in humans.

Adult↗
PubMed2003

[Clinical comparison between guided tissue regeneration and induced tissue regeneration].

AIM: The aim of the present study was to evaluate, over a period of 1 y, 3 different surgical methods for the treatment of periodontal bone defects. METHODS: Thirty-six infrabone defects, at least 4 mm in depth, in non-smokers were enrolled in the study. Of these, 12 were treated with guided tissue regeneration (GTR) using a resorbable membrane with collagen, 12 with enamel matrix derivative (EMD) gel and 12 with a modified Widman flap (MWF). The pocket depth, attachment loss and gingival recession both before commencement of therapy and after an interval of 1 y are reported. RESULTS: The reduction in pocket depth was 4 mm, 4.4 mm, and 4.5 mm, respectively, for the control group, GTR group and EMD group. The attachment gain for the respective treatments was: MWF, 2 mm; GTR, 2.8 mm; EMD, 2.9 mm. Gingival recession was: MWF, 1.8 mm; GTR, 1.5 mm; EMD, 1.1 mm. CONCLUSION: These findings show the efficacy of the 3 methods in the treatment of bone defects, but none of the 3 emerges as being statistically superior to the others 2.

Adult↗
PubMed2001

An exceptional case of complete neurologic recovery after more than 5-h cardiac arrest.

We describe a case of more than 5 h cardiac arrest in a 60-year-old patient who underwent general anesthesia for a urologic operation. Before extubation, the patient suddenly developed ventricular fibrillation, pulseless ventricular tachycardia and asystole which was immediately treated by advanced life support (ALS) measures. Thirty minutes later seizures developed and were controlled by 200 mg of thiopentone and 10 mg of diazepam. A pattern of ventricular tachycardia, coarse ventricular fibrillation and asystole lasted for nearly 120 min. Termination of resuscitation maneuvers was considered, but long-term life support was continued for 5 h. After this time, peripheral pulses, with a supraventricular tachycardia-like rhythm and regular spontaneous breathing reappeared. Seven hours later, the patient had a Glasgow Coma Scale (GCS) of 5, dilated unresponsive, absence of pupils, and a systolic arterial pressure of 100 mmHg. He was then transferred to intensive care unit (ICU). The morning after, the patient was awake, responded to simple orders, breathing spontaneously, and free from sensomotor deficit. He was, therefore, extubated. Subsequently, other episodes of transitory ST-line upper wave followed by ventricular fibrillation appeared, suggesting Prinzmetal angina. This was successfully treated by percutaneous coronary angioplasty. The first electroencephalogram recorded the day after cardiac arrest showed a mild widespread background slowing. An electroencephalogram 6 days later showed a return to alpha rhythm with only mild theta-wave abnormalities. Four weeks after the first cardiac arrest the patient was discharged. This is an exceptional experience compared with the others reported. We believe that all the efforts must not be given up when such an event occurs during anesthesia and there are optimal conditions for resuscitation maneuvers.

Cardiopulmonary Resuscitation↗
PubMed2000

Sustained kilowatt lasing in a free-electron laser with same-cell energy recovery

Jefferson Laboratory's kW-level infrared free-electron laser utilizes a superconducting accelerator that recovers about 75% of the electron-beam power. In achieving first lasing, the accelerator operated "straight ahead" to deliver 38-MeV, 1.1-mA cw current for lasing near 5 &mgr;m. The waste beam was sent directly to a dump while producing stable operation at up to 311 W. Utilizing the recirculation loop to send the electron beam back to the linac for energy recovery, the machine has now recovered cw average currents up to 5 mA, and has lased cw with up to 1720 W output at 3.1 &mgr;m.

Journal Article↗
PubMed2000

Event-related potentials in patients with total locked-in state due to fulminant Guillain-Barré syndrome.

A series of electrophysiological investigations were performed over a 6-month period in two patients affected by fulminant Guillain-Barré polyradiculoneuropathy, who developed an ascending paralysis leading, within 72 h, to flaccid quadriplegia, internal and external ophthalmoplegia, absence of all brainstem reflexes and no respiratory effort: the clinical state resembled brain death. Brain CTs were normal and spinal fluid examination revealed albuminocytological dissociation. All motor nerves tested were unexcitable, whereas sensory responses were markedly abnormal but present. Sequential EEG recordings revealed normal, partially reactive alpha rhythm in both patients. In one patient, normal auditory event-related potentials (ERPs: peak N1, P2, N2, P3, evoked in an 'oddball' paradigm) and CNV-like potentials could be recorded not earlier than the 20th day into the illness. In earlier recordings, N1 and P2 peaks as well as mismatch negativity (MMN) were present over the frontal and central scalp electrodes. This patient has now partially recovered motor functions and no cognitive defects are present, but he has little recollection of the events occurring in the first 2 weeks spent in the ICU, when he was completely paralyzed. The other patient generated normal N1 and P2 ERP peaks, but no N2, P3 and MMN were detected in a series of recordings. He died without having ever regained appropriate behavioral responses. The ERP abnormalities observed raise the matter of the origin of cognitive dysfunction in patients with severe and prolonged de-efferentation/de-afferentation. ERPs allow monitoring the level of alertness and attention and appear more specific than EEG in identifying a state of awareness in patients in which communication is severely impaired as a consequence of neurological disorders.

Adult↗
PubMed1996

Working memory in temporal lobe epilepsy: an event-related potential study.

Event-related potentials (ERPs) were recorded to a digit-probe identification and matching task (modified 'Sternberg paradigm') in 29 patients with temporal lobe epilepsy (TLE) and 26 healthy subjects. Our main aim was to identify the neurophysiological correlates of abnormal short term memory function in patients with TLE. Neuropsychological tests allowed the definition and comparison of two patient groups according to the presence or absence of memory dysfunction. These two groups did not differ significantly in mean age, education years, IQ, seizure duration, seizure frequency, anti-epileptic drug (AED) regimes, or on findings on neuroimaging. ERPs recorded under different levels of memory load were analysed both by conventional component identification and by an objective computer method of determining mean amplitudes of multiple 50 ms epochs (MMA analysis). We found that some significant abnormalities were common to both groups of patients; these included slow reaction times, a reduced amplitude of the N170 wave (and the corresponding 157-210 ms epoch in the MMA analysis) and a broad late negative shift between 577 and 735 ms. Other findings, including a significantly reduced performance accuracy as the level of memory load increased, were restricted to patients with abnormal memory function. The ERP changes that were specific to these patients occurred within a latency band of 200-420 ms and included a relatively preserved, but delayed P250 component and a delayed and attenuated N290 wave. When compared with either healthy subjects or with patients with normal memory, the responses in patients with abnormal memory showed an abnormal 'positive shift' between 262 and 315 ms after probe presentation and a further positive shift between 315 and 420 ms as memory load increased. These abnormalities of 'memory scanning' ERPs in patients with TLE which paralleled neuropsychological and behavioural evidence of memory dysfunction, and which occurred in the section of the response that is sensitive to memory loading in healthy subjects, provide further objective evidence that abnormalities of short term memory processes contribute to the memory deficits of TLE.

Adult↗
PubMed1993

Electrophysiological study of neurologically asymptomatic HIV1 seropositive patients.

EEGs, brainstem auditory evoked potentials (BAEPs) and auditory event-related potentials (ERPs) were recorded from 33 individuals infected with the human immunodeficiency virus, type 1 (HIV1+ patients: 13 CDC Class II or III; 20 Class IV). All were neurologically asymptomatic, non-demented, and had a past history of intravenous drug abuse. Sixteen age- and sex-matched normals and 10 HIV1- former drug addicts served as controls. Half of the HIV1+ and HIV1- subjects displayed mild EEG anomalies and, except for one HIV1+ patient, BAEPs were normal in both groups. ERPs were normal in all HIV1- subjects but anomalous (longer latencies of components P2, N2, P3; reduced amplitude of P3) in 9 HIV1+ patients (27%), the incidence of such anomalies being higher for Class IV than Class II/III patients. Auditory ERPs proved the most sensitive and specific of these electrophysiological procedures in detecting subclinical central nervous system involvement in HIV1 infection.

Adult↗
PubMed1992

Electrophysiologic study of HIV-1 + patients without signs of peripheral neuropathy.

HIV-1 seropositive patients have a high frequency of nervous system diseases, and asymptomatic abnormalities are frequently detected. We studied 124 neurologically asymptomatic HIV-1 seropositive subjects and 23 normal control subjects by nerve conduction studies. No alterations were detectable in the asymptomatic stages of infection (CDC groups II and III), while subclinical peripheral nervous system (PNS) impairment was detected in symptomatic HIV-1 stages (CDC group IV). Specifically, in CDC group IV we observed a reduction in the motor conduction velocity of the deep peroneal nerve and the median nerve, and a similar reduction of the sensory conduction velocity of the sural nerve. There were no differences of the amplitude and area of the muscular response or of the sensory nerve action potential. As our patients did not present clinical or laboratory evidence for a toxic-dismetabolic etiology, our data indicate a progressive myelin damage more directly related to HIV-1 infection. This subclinical finding may have importance for the progression of the disease in the PNS.

Action Potentials↗
PubMed1992

Peripheral and central nervous system anomalies in HIV-1 infection: an electrophysiological study.

This study explored the neurophysiological changes in 87 HIV1+ (20 AIDS, 24 ARC, 24 LAS and 19 AC) patients showing no clinical evidence of neurological impairment. Tracing somatosensory responses by recording SEPs from upper and lower limbs, we found a slowing of both peripheral and central nerve conduction. Peripheral alterations occurred in virtually all patients of the AIDS group. Central anomalies, confined largely to the lower spinal cord, manifested themselves only during the later stages of the disease (ARC and AIDS) and then only in about half of our sample. More marked neurotropic varieties of HIV1 may account for these differences. We feel that SEP studies can serve to reveal pre-clinical NS involvement in HIV1+ subjects and should be included among research strategies aimed at tracing the evolution of AIDS.

Adult↗
PubMed1990

Intrathecal synthesis of anti-HIV antibodies in AIDS patients.

We studied the production within the CNS of anti-HIV antibodies, of non-specific IgG, and the presence of HIV antigens in the serum and CSF of 28 HIV infected patients belonging to group IV in the Center for Disease Control classification. CSF and serum were diluted under optimal conditions to equalize their IgG content, to enable us to better interpret serum and CSF reactivity by means of Western blot and ELISA. Under these conditions, no patient displayed a limited immunological response profile in CSF as compared to serum. On the contrary, there was intrathecal synthesis (ITS) of anti HIV-antibodies in Western blot test in 21 patients for gp160 and ITS was demonstrable for env, gag, and pol products. ITS of anti-HIV antibodies occurred in 17 patients when measured by ELISA. ITS of non specific IgG and HIV-antigens in CSF were less frequent. A marked anti-HIV response is evident in the CSF-CNS compartment in the later phases of the HIV infection.

AIDS Dementia Complex↗
PubMed1990

Neurological involvement in group iv HIV-positive patients. Neurophysiological and clinical data.

Spinal and cortical SEP responses were recorded during tibial and median nerve stimulation in 58 HIV+ subjects (8 IV/C1, 24 IV/C2 & IV/A, 11 III and 15 II), all asymptomatic from a neurological point of view. The electrophysiological features were compared with clinical assessment and serum HIV markers for purposes of prognosis and therapy. In group IV we observed a slowing of conduction along the afferent pathway in the spinal tracts and afferent ways to the cortex. The major part of the delay occurred in the mid and lower medullary tract. These results agree with neuropathological finding from post-mortem examination in AIDS pts.

Acquired Immunodeficiency Syndrome↗