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PubMed1993

[Fetal heart rate monitoring in the prenatal diagnosis of cord position abnormalities].

External monitorings of fetal heart rate in 2,628 cases of cord around the neck and funis presentation from June 1985 to June 1991 were analysed. The positive rate was 81.66% and the pseudo-negative rate 18.34%. 1,680 cases (63.93%) with variable deceleration were observed. Among them V wave was seen in 745 monitorings (28.53%), mostly due to umbilical compression: U wave in 238 monitorings (9.06%), mostly due to intrauterine asphyxia; and W wave in 223 monitorings (8.49%), more due to cord compression and funis presentation but also due to acute fetal intrauterine anoxia, rebound acceleration and rebound deceleration wave was observed in 316 monitorings (12.02%), more due to cord compression. The remaining 158 monitorings (6.01%) showed mixed waves. There were 51 perinatal deaths including 6 fetal, 5 still births, and 40 neonatal deaths. The perinatal mortality rate was 19.41%. The relationship among the monitor waves, the fetal growth, umbilical cord, nature of the amnionic fluid, Apgar score, etc, immediately after delivery was analyzed and the clinical significance was discussed. It was suggested that Nipple Stimulation Contraction Stress Test (NS-CST) or Contraction Stress Test (CST) could be used as a good method for prenatal diagnosis.

Adult↗
PubMed1993

Monitoring premature infants in car seats: implementing the American Academy of Pediatrics policy in a community hospital.

OBJECTIVES: In 1990, the American Academy of Pediatrics (AAP) Committee on Injury and Poison Prevention issued a policy statement which recommended that all infants born at less than 37 weeks gestational age be monitored in their car seat before discharge to identify infants at risk for apnea associated with car seat use. The objective of this report is to summarize the experience of a community hospital in implementing this recommendation, including: education of health professionals about the problem and its management, development of an effective hospital policy and procedure for testing at-risk infants, overcoming logistical difficulties for nursing staff who implement the policy, overcoming liability concerns, and summarizing the clinical results which we observed during a 15-month period. METHODS: MetroWest Medical Center, Framingham Union Campus is a community hospital with a Level II Neonatal Unit with approximately 2200 deliveries annually. Hospital procedures and policies were developed to implement the AAP policy for safe transportation of premature infants. Consequently, infants less than 37 weeks gestation at birth were monitored for a 90-minute observation period for oxygen saturation, apnea, or bradycardia in the car seat that they would be going home in from the nursery. RESULTS: Policies and procedures for car seat monitoring were instituted successfully during 15-month period. Sixteen of 87 (18.4%) monitored infants 26 to 36 weeks gestation had abnormal results. In addition, one 37-week gestational newborn who was monitored because of duskiness during feeds also became apneic and bradycardic in the car seat. CONCLUSIONS: A car seat monitoring program can be incorporated effectively into a Level II community hospital nursery discharge plan provided that appropriate medical staff policies, nursing procedures, and administrative support to deal with the logistics of the program is established. Our monitoring results are consistent with previous reports that premature infants are at risk of desaturation in a car seat. In addition, we have demonstrated that a full-term neonate may also be at risk if other evidence of desaturation (eg, duskiness during feedings) is observed.

Apnea↗
PubMedDate not supplied

A comparison of conventional versus electronic monitoring of sedated pediatric dental patients.

The first purpose of this study was to compare traditional monitoring methods to electronic instruments for monitoring physiologic parameters during conscious sedation of pediatric dental patients. Traditional methods included careful visual assessment of skin color, airway patency and chest movements, and auscultation of breath and heart sounds using a precordial stethoscope; electronic instruments included the capnograph and pulse oximeter. The second purpose of the study was to examine the potential of the capnograph to provide more advanced warning than the pulse oximeter for respiratory compromise. Thirty-nine children (mean age 39 months) received an oral sedative regimen of chloral hydrate, hydroxyzine pamoate, and meperidine and all were supplemented with 100% oxygen via nasal cannula throughout their sedations. One investigator used traditional monitoring and the other used electronic--both monitored simultaneously while being shielded (blinded) from each other. Electronic monitoring yielded a false alert rate of 88% compared with 73% for traditional monitoring. Ten confirmed episodes of respiratory compromise were identified electronically and only three were identified by traditional monitoring. All of the 10 confirmed respiratory compromise episodes were detected by capnography; none were detected by oximetry. During these 39 pediatric sedations using a narcotic drug regimen and 100% oxygen supplementation, there were no true desaturations.

Anesthesia, Dental↗
PubMed1995

Hemodynamic monitoring in the critically ill.

Monitoring of vital functions is one of the most important and essential tools in the management of critically ill patients in the ICU. Today it is possible to detect and analyze a great variety of physiological signals by various noninvasive and invasive techniques. An intensivist should be able to select and perform the most appropriate monitoring method for the individual patient considering risk-benefit ratio of the particular monitoring technique and the need for immediate therapy, specific diagnosis, continuous monitoring and evaluation of morphology should be included. Despite rapid development of noninvasive monitoring techniques, invasive hemodynamic monitoring in still one of the most basic ICU procedures. It enables monitoring of pressures, flow and saturation, pressures in the systemic and pulmonary circulation, estimation of cardiac performance and judgment of the adequacy of the cardiocirculatory system. Carefully and correctly obtained information are basis for proper hemodynamic assessment which usually effects the therapeutic decisions.

Critical Illness↗
PubMed1995

[Portable home monitoring system in screening for sleep-disordered breathing].

Screening for sleep-disordered breathing is often done in an interview and with a questionnaire. This method is indirect and it appears to underestimate the prevalence of sleep apnea syndrome. Recently, several devices such as the Medilog and Vitalog portable monitoring systems were developed. However, these devices are difficult for patients to operate by themselves, because they include EEG monitoring or measurement of chest and abdominal movement. Therefore, we developed a portable monitoring system that is easier to operate. This system can be used to assess three variables: oronasal airflow, tracheal sound, and electrical activity of the heart. It stores the time of the onset of apnea, apnea duration, and R-R intervals with a built-in microcomputer. Apnea episodes, total apnea time, mean apnea time, and R-R interval are analyzed with a host computer. The sensitivity an specificity of this system are 92.5% and 87.5%, respectively, with an apnea index (AI) of less than 10 episodes/h. Using this device, we found that the prevalence of sleep apnea syndrome among Japanese industrial workers who had an AI of more than 10 episodes was 7.5%. Moreover, from 1984 to 1994 we used this device to monitor 1019 outpatients who complained of sleep disturbances such as snoring, abnormal breathing during sleep, and excessive daytime sleepiness, and found sleep apnea (AI > or = 10) in about 50% of these patients. This monitoring system is useful for screening of outpatients with sleep apnea and for epidemiological studies of sleep apnea. However, it may be necessary to include a non-invasive system for monitoring oxygen saturation in the portable sleep monitor, to detect hypoventilation during sleep.

Adolescent↗
PubMed1996

Occupational health monitoring practices of registered mercury-using workplaces within Gauteng.

OBJECTIVES: To assess monitoring practices of workplaces registered as mercury users within the then PWV South region of the Department of Manpower (now Gauteng region of the Department of Labour); to identify the main industrial sectors that use mercury and to estimate the number of workers potentially exposed. DESIGN: A descriptive study design was used. SETTING: Workplaces situated in the former PWV South region, as defined by the Department of Manpower. SUBJECTS: Fifty-eight workplaces were registered as mercury users in this region. Postal questionnaires were sent to 34 workplaces on the Department of Manpower's list of mercury users-24 were excluded because they had closed, moved or claimed, on telephonic contact, no longer to use mercury. MAIN OUTCOME MEASURES: Industry type and form of mercury used, monitoring practices and attitudes to legislation. RESULTS: The response rate to the questionnaire was 73.5% (25). Despite being registered as users, 52% (13) of the respondents claimed not to use mercury. Of the 10 mercury-using workplaces, 5 conducted biological monitoring, while only 2 performed environmental measurements. Six of the 10 workplaces used an inorganic form of mercury, 3 used a combination of inorganic and organic mercury, while 1 used organic mercury only. Sixty per cent of all respondents would support legislation that regulated monitoring of mercury in industry. CONCLUSIONS: The study suggests that biological monitoring of mercury is conducted by a limited number of users in Gauteng, while environmental monitoring appears to be neglected. Recently enacted legislation for industrial mercury monitoring needs to be implemented rigorously. Since more than half of the respondents claimed not to use mercury, even though they were registered as users with the Department of Manpower, the study further demonstrates a need to review the system of registration and record-keeping.

Environmental Monitoring↗
PubMedDate not supplied

[Obligatory monitoring methods during delivery].

Fetal monitoring by cardiotocogram (CTG), fetal blood gas analysis (FBA) and pulse oximetry are mostly accepted by obstetricians. Other new methods are in discussion. Cost, benefit and need of the different methods are in continuous controversy. Successful screening by monitoring is focused on early detection and prevention of fetal asphyxia. Through the predictive value of fetal acidosis by CTG is only 30%, the cardiotocogram is the accepted standard method of fetal monitoring. In cases of difficult assessment of intrapartum CTG (4-6%) additional FBA is recommended. Perinatal statistics demonstrate no advantage of continuous monitoring. Intermittent electronic monitoring therefore is possible in deliveries without risk factors. The increasing rate of cesarean sections is followed by defensive medicine and not caused by fetal monitoring. Provided standards of fetal monitoring severe asphyxia in newborns with more than 1500 g is expected in 1:5,000 to 1:10,000 deliveries. The benefit of additional methods therefore seemed to be hardly to prove by prospective trials.

Asphyxia Neonatorum↗
PubMed1997

Critical care monitoring for cerebrovascular disease.

Frequent or continuous monitoring of crucial variables in patients with cerebrovascular disease allows the intensive care team to identify progression of the pathophysiologic mechanisms involved, intervene to halt or reverse this progression, and identify the response to treatment in order to modify the intervention if necessary. Central nervous system physiologic monitoring modalities include: a) the clinically-apparent function, b) physical and mechanical variables, c) circulation or perfusion, d) bioelectrical measures, and e) biochemical measures. The neurologic examination of the critically ill patient is an indispensable monitoring tool in the ICU. Patterns of neurologic signs and the trend of the examination, whether worsening or improving, are the most important factors to follow because there is no single sign or symptom which forecasts impending disaster. Intracranial pressure monitoring is applicable to all subsets of cerebrovascular disease, providing information about cerebral perfusion pressure and risk of secondary cerebral injury. Cerebral blood flow is not easily quantified in the ICU, but transcranial Doppler sonography is a reliable bedside technique that can be used for intermittent or continuous monitoring. Neurophysiologic monitoring with electroencephalography (EEG) and evoked potential (EP) testing can be used as a supplement to the neurologic exam and other diagnostic studies. EEG and EP can provide an early indication of clinically relevant change due to evolving disease or in response to therapy, which is especially helpful when the neurologic examination is limited due to severe coma, therapeutic barbiturate coma, or neuromuscular blockade. Neurometabolic monitoring in cerebrovascular disease with microdialysis is a promising technique that may be able to identify markers of cellular energy state or excitotoxicity in carefully selected areas of the brain.

Cerebrovascular Circulation↗
PubMedDate not supplied

[Intraoperative facial nerve monitoring. Practical remarks].

OBJECTIVE: Even the most experienced surgeon may have difficulties in identifying and preserving the facial nerve, particularly when the operation is complicated, for example, by size and localization of tumour, trauma or anatomic variations. The aim of this study is to present indications, technics and interpretation of intraoperative facial nerve monitoring. METHODS: This study bases on literature review and our own experience in intraoperative facial nerve monitoring. CONCLUSIONS: Intraoperative facial nerve monitoring is helpful during excision of large and middle size acoustic neuromas, because preservation of facial nerve function improves with use of electrical monitoring. Intraoperative monitoring during other kinds of operation, which are likely to impact on the facial nerve may also be of benefit. This however, is hardly proved in the literature. Its seems, that electrical intraoperative monitoring is more sensitive than pneumatic motion detector system. Intraoperative monitoring is an adjunct, not replacement, to surgeon's experience and ability. The presence or absence of facial evoked responses must be interpreted within the context of surgical procedure, bearing in mind possibility the of false-positive and false-negative errors.

Electromyography↗
PubMed1998

Advances in monitoring of seventh and eighth cranial nerve function during posterior fossa surgery.

OBJECTIVE: This study aimed to illustrate some recent advances in intraoperative monitoring of the seventh and eighth cranial nerves (i.e., direct recording of cochlear nerve action potentials [CNAPs] and facial nerve action potentials [FNAPs]). STUDY DESIGN: Reports of representative cases and average postoperative results obtained in subjects submitted to cerebellopontine angle surgical procedures are examined. Results obtained in patients with direct recording techniques are compared with those obtained with the classical monitoring techniques (auditory brain stem response [ABR], electrocochleography [ECoG], facial electromyography [EMG]). SETTING: The study was conducted at an Ear Nose and Throat Department, University of Verona, Verona, Italy. INTERVENTION: Intraoperative monitoring during cerebellopontine angle surgery was performed. RESULTS: Patients monitored with direct audiomonitoring techniques presented better postoperative auditory functions compared to patients monitored with ABR. The FNAP and EMG groups showed FN outcome that did not differ significantly. CONCLUSIONS: Intraoperative monitoring of cranial nerves furnishes a valid tool for identification of neural structures, prevention of damage, understanding of the pathophysiology of damage, and prediction of postoperative function. The fundamental prerequisite for obtaining optimal benefits from monitoring is the use of techniques of direct and continuous electrophysiologic recording with instantaneous feedback to the surgeon, such as CNAPs and FNAPs.

Adolescent↗
PubMed1998

Antibiotic prophylaxis for intracranial pressure monitors.

To determined the safety and efficacy of prophylactic antibiotics in head-injured patients requiring intracranial pressure monitors, the files of 30 consecutive patients with isolated, severe head injuries admitted over a 1-year period were reviewed. Patients .15 years with severe closed-head injury who did not have severe concomitant, extracranial injury (Abbreviated Injury Score, 3) and survived .48 hours following hospital admission were included. Fourteen patients underwent intracranial pressure monitor placement and received prophylactic antibiotics for the duration of monitoring and the remaining 16 patients were neither monitored nor given prophylactic antibiotics. Length of hospital stay, length of intensive care stay, overall and septic complication rate, and death rate were compared for the two treatment groups. The groups were similar with regard to patient characteristics, associated injuries, and injury severity. Patients who received prophylactic antibiotics demonstrated statistically higher septic morbidity rates (78.6% versus 31.3%) and statistically higher pneumonia rates (57.1% versus 18.8%) compared with patients who did not. No patient developed central nervous system infection related to the monitor itself. These results indicate that the administration of prophylactic antibiotics to head-injured patients for the duration of intracranial pressure monitoring is unnecessary and potentially detrimental. Antibiotics, if given at all, should be limited to the period immediately surrounding intracranial pressure monitor placement.

Adult↗
PubMed1997

Adverse drug reaction monitoring--cost and benefit considerations. Part I: frequency of adverse drug reactions causing hospital admissions.

In an era of health care cost containment it is of particular interest to identify measures that reduce costs and at the same time improve health care quality. One of these cost cutting measures might be the reduction of the frequency of Adverse Drug Reactions (ADR). The objective of this paper is to summarize all original work on ADR frequencies at hospital admission and to come up with a valid estimate for the actual frequency of ADR-related hospital admissions. Additionally, we compared established concepts of ADR monitoring with respect to their utility for drug safety monitoring and pharmacoepidemiologic research. We reviewed 25 studies from the past 25 years. Analysing the effect of methodological characteristics showed that variation of reported ADR frequency mainly depends on differing study bases and the concepts of ADR monitoring. Investigations that thoroughly screened all members of the study population for the presence of adverse drug reactions (comprehensive ADR monitoring) generally yielded highest ADR proportions. Studies that concentrated screening on selected high-risk patients (preselective ADR monitoring) and those applying spontaneous or intensified spontaneous reporting detected lower ADR proportions (2.9% and 2.5%). The ADR proportion among admissions to departments of internal medicine was higher than among mixed hospital populations including surgical patients. In conclusion 4.2-6.0% (lower and upper quartile) and in median 5.8% of all admissions to medical departments are caused by adverse drug reactions. A two-step preselective ADR monitoring appears to be appropriate and efficient for both signal generation and signal validation as compared to spontaneous reporting and comprehensive monitoring. In conclusion, adverse drug reactions are a common cause of hospital admissions. As hospital care is expensive, attempts to prevent ADR and thus hospital admission need active encouragement.

Journal Article↗
PubMed2006

Fetal electrocardiogram (ECG) for fetal monitoring during labour.

BACKGROUND: Hypoxaemia during labour can alter the shape of the fetal electrocardiogram (ECG) waveform, notably the relation of the PR to RR intervals, and elevation or depression of the ST segment. Technical systems have therefore been developed to monitor the fetal ECG during labour as an adjunct to continuous electronic fetal heart rate monitoring with the aim of improving fetal outcome and minimising unnecessary obstetric interference. OBJECTIVES: To compare the effects of analysis of fetal ECG waveforms during labour with alternative methods of fetal monitoring. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2006). SELECTION CRITERIA: Randomised trials comparing fetal ECG waveform analysis with alternative methods of fetal monitoring during labour. DATA COLLECTION AND ANALYSIS: Trial quality assessment and data extraction were performed by the review author, without blinding. MAIN RESULTS: Four trials including a total of 9829 women were included. In comparison to continuous electronic fetal heart rate monitoring alone, the use of adjunctive ST waveform analysis (three trials, 8872 women) was associated with fewer babies with severe metabolic acidosis at birth (cord pH less than 7.05 and base deficit greater than 12 mmol/L) (relative risk (RR) 0.64, 95% confidence interval (CI) 0.41 to 1.00, data from 8108 babies), fewer babies with neonatal encephalopathy (three trials, RR 0.33, 95% CI 0.11 to 0.95) although the absolute number of babies with encephalopathy was low (n = 17), fewer fetal scalp samples during labour (three trials, RR 0.76, 95% CI 0.67 to 0.86) and fewer operative vaginal deliveries (three trials, RR 0.87, 95% CI 0.78 to 0.96). There was no statistically significant difference in caesarean section (three trials, RR 0.97, 95% CI 0.84 to 1.11), Apgar score less than seven at five minutes (three trials, RR 0.80, 95% CI 0.56 to 1.14), or admissions to special care unit (three trials, RR 0.90, 95% CI 0.75 to 1.08). Apart from a trend towards fewer operative deliveries (one trial, RR 0.87, 95% CI 0.76 to 1.01), there was little evidence that monitoring by PR interval analysis conveyed any benefit. AUTHORS' CONCLUSIONS: These findings provide some support for the use of fetal ST waveform analysis when a decision has been made to undertake continuous electronic fetal heart rate monitoring during labour. However, the advantages need to be considered along with the disadvantages of needing to use an internal scalp electrode, after membrane rupture, for ECG waveform recordings.

Cardiotocography↗
PubMed2003

Monitoring by rheumatologists for methotrexate-, etanercept-, infliximab-, and anakinra-associated adverse events.

OBJECTIVE: To determine what monitoring protocols rheumatologists use to identify adverse events in rheumatoid arthritis (RA) patients treated with methotrexate (methotrexate), etanercept (etanercept), infliximab (infliximab), and anakinra (anakinra), how often rheumatologists encounter treatment-altering adverse events in their RA patients receiving these treatments, and how they feel about and comply with the current monitoring guidelines. METHODS: Three hundred ten physician members of the American College of Rheumatology (ACR) were notified by e-mail of a survey that was posted on our rheumatology Web site. Questions were closed-ended and multiple choice in format. RESULTS: One hundred twenty-three responses were received (40%). Most rheumatologists reported that they utilize the ACR recommended screening tests at baseline before methotrexate treatment is initiated. Seventy-nine percent reported that treatment-altering abnormalities had occurred in <5% of their methotrexate-treated RA patients, and 88% reported that such abnormalities had occurred in <10% of such patients, in the previous 3 years. Forty-one percent believed liver function monitoring guidelines need to be changed; 59% said they would agree with new guidelines that would include a recommendation for liver function monitoring every 3-4 months. Most rheumatologists were not aware of any guidelines for monitoring by blood tests in RA patients treated with biologic agents, yet the majority reported that they order blood tests before patients start these therapies and on followup. CONCLUSION: Our survey indicates that treatment-altering liver function abnormalities in methotrexate-treated RA patients are rare, and more than half of rheumatologists agree that a less stringent monitoring regimen should be considered. Rheumatologists and pharmaceutical companies might work together to develop guidelines for monitoring of patients treated with biologic agents.

Adverse Drug Reaction Reporting Systems↗
PubMed1998

Why does monitoring fail in jargon aphasia? comprehension, judgment, and therapy evidence.

Many people with jargon aphasia seem unaware of their speech disorder. The first section of this paper reports data from four subjects which indicate that self-monitoring can fail even when subjects' input skills are apparently adequate to detect their errors. Explanations for this dissociation have attributed monitoring failure to a deficit in auditory feedback, or to a resource limitation which prevents concurrent speaking and monitoring. Section 2 reports a series of naming and judging experiments with one of the subjects which rule out these explanations. These show that the subject can detect his neologisms when he is repeating, but not when he is naming. These results suggest that his monitoring difficulties arise when he is accessing phonology from semantics. Section 3 presents a study which supports this inference, since it shows that semantically focused intervention yields improvements in self-monitoring. It is concluded (1) that monitoring failure can arise from deficits within the production process which preclude comparison of actual with intended output, and (2) that this deficit is best explained within a connectionist model in which monitoring is performed by feedback mechanisms in the word production process.

Aged↗
PubMed2000

Video-intuboscopic monitoring of tracheal intubation in pediatric patients.

PURPOSE: To evaluate the efficacy of video-intuboscopic monitoring during orotracheal intubation in a pediatric anesthesia teaching unit. METHODS: In 100 pediatric patients direct laryngoscopy performed by residents or nurse anesthetists was monitored on a video display using a flexible, ultralight video-endoscopic system (O.D. 2.8 mm/length 1.8 m) within the endotracheal tube (ETT). Best direct laryngoscopic view was assessed by the intubator. The instructor observed the intubation procedure on the video display and noted number of intubation attempts, best laryngoscopic monitor view, tube passage through the larynx and final tube position. If required he gave instructions or corrections. After removal of the laryngoscope, tracheal tube position was adjusted using the monitor view. Difficulties attributed to the fibreoptic endoscope during intubation and removal from the ETT were recorded. RESULTS: The trachea was successfully intubated at the first attempt in all patients. The supervisor detected one esophageal and 12 endobronchial intubations that were immediately corrected before starting ventilation. Final visualized endotracheal tube adjustment above the carina was possible in all patients except in one with copious tracheal secretions. Compared with direct laryngoscopy the video display provided an improved view of the vocal cords during intubation. In six patients direct laryngoscopy was difficult but the tracheas were intubated using the monitor view. No difficulties with the equipment were encountered except that the black coated endoscope compromised recognition of the black ETT depth-markings in small tubes. CONCLUSIONS: Video-intuboscopic monitoring is a useful monitor of tracheal intubation. "The improved view of the cords may provide assistance during difficult laryngoscopy.

Adolescent↗
PubMed2003

Effect of the angle between the optical axis of the endoscope and the instruments' plane on monitor image and surgical performance.

BACKGROUND: The aim of the study was to examine the effect of the angle between optical axis of the endoscope and the instruments' plane (OAIP) on the monitor display angle (approach angle between the two instruments on a two-dimensional monitor) and endoscopic task performance. METHODS: Two experiments were carried out in the Advanced Dundee Endoscopic Psychomotor Tester (ADEPT) using a standard two-dimensional video endoscopic system. In the first experiment, the monitor display angle was measured during use, with OAIP angles ranging between 0 and 80 degrees (at 10 degrees increments) and manipulation angles varying between 45 and 120 degrees (at 15 degrees increments). In the second experiment, 10 surgeons tied 500 intracorporeal knots with OAIP angles of 0 degrees (optical axis in the same plane as the instruments), +15 degrees and +30 degrees (viewing above the instruments' plane), and -15 and -30 degrees (optical axis looking from below instruments' plane). The end points were the execution time and knot quality score (KQS). RESULTS: In the first experiment, instruments entered the visual field from lateral sides of the monitor with an apparent 180 degrees monitor display angle with a 0 degrees OAIP angle, whereas the monitor display angle approached the actual manipulation angle between the two needle drivers when an 80 degrees OAIP angle was used. In the second experiment, the instruments appeared to enter the image field from the side of the surgeon when the endoscope viewed the instruments from above, whereas instruments entered the field from the opposite side to the surgeon when the endoscope viewed instruments' plane from below. As a result, use of 0 and +15 degrees OATP angles yielded significantly shorter execution times: 70 s compared to 83, 93, and 77 s for +30, -30, and -15 degrees OAIP angles ( p < 0.001), with KQS of 39 degrees and 40 vs 38, 36, and 34%, respectively ( p = 0.257). CONCLUSIONS: The angle between the optical axis of the endoscope and instruments' plane determines how the instruments appear to enter the operative field. The monitor display angle between the instruments is different from the real manipulation angle unless the OAIP angle is near 80 degrees. The apparent entry of instruments into the operative field becomes intuitive for the surgeon only if the endoscope is viewing from above or in the same plane as the instruments. Hence, the best performance for endoscopic knot tying is obtained with this configuration, and execution time increases significantly with viewing from below the instruments' plane.

Endoscopes↗
PubMed2001

Spinal cord stimulation and early experimental cerebral spasm: the "functional monitoring" and the "preventing effect".

BACKGROUND: Clinical and experimental data on cerebral blood flow (CBF) changes during spinal cord stimulation (SCS) were published since 1986. The aims of the present work are: 1. To find an experimental model of reliable, simple and in vivo monitoring of "early" basilar artery spasm after subarachnoid haemorrhage (SAH) and 2. To investigate the effects of cervical spinal cord stimulation (CSCS) on it. Vasospasm due to SAH is both "acute" and "recurrent". Early spasm occurs within minutes of the SAH. its duration is approximately 1 hour. The need of different morphological and haemodynamic methods to evaluate experimental early spasm is reported. To overcome intracranial surgical manipulations and biological effects of contrast and fixation media we designed a model that allows "in vivo" functional monitoring of basilar blood flow far away from the spasm without direct surgical and chemical interference. Subsequently we investigated the effects of CSCS on the new model of "functional monitoring" of the "early" cerebral vasospasm. METHOD: 29 adult Burgundy rabbits were studied. Group 1: under homeostatic monitoring, "on-line" carotid blood flow (carotid BF) changes produced by SAH in cisterna magna of 12 (plus 5 sham treated) animals were studied from the common carotid artery after external carotid artery occlusion before, during SAH and up to the end of the experiments. All the animals underwent digital subtraction cerebral panangiography (CPA) after SAH obtaining a significant increase of carotid BF only when basilar vasospasm was shown by CPA. Carotid BF increase during basilar vasospasm was defined "functional monitoring" of early spasm. Group 2: Twelve animals wearing a cervical epidural electrode underwent carotid BF "functional monitoring" of early basilar spasm before and during CSCS. FINDINGS: Carotid BF changes during CSCS occurred in 10 animals. No carotid BF changes (i.e. no basilar vasospasm) occurred after SAH up to the end of the experiments in all the stimulated animals. INTERPRETATION: CSCS is able to prevent "early spasm" due to SAH in all the animals studied with the new model of "functional monitoring" described, independently from the occurence and the sign for stimulation-induced carotid BF variations. The role and the limits of reversible functional sympathectomy in mediating the effect of CSCS on early vasospam are discussed.

Acute Disease↗