Magnetic field interactions of smartwatches and portable electronic devices with cardiovascular implantable electronic devices

Funding Acknowledgements

Type of funding sources: None.

Introduction

Magnetic interference of portable electronic devices (PEDs), such as state-of-the-art mobile phones, with cardiovascular implantable electronic devices (CIEDs) has been reported.

Purpose

The aim of the study was to quantify the magnetic fields of latest generation Smartwatches and other PEDs and to evaluate and predict their risk of CIED interactions.

Method

High resolution magnetic field characterization of five smartwatches able to record an ECG Apple Watch, Series 6 and 7, Fitbit Sense, Samsung Galaxy Watch 3, and Withings Move ECG Watch was performed using a magnetic field camera consisting of 1024 calibrated three axis Hall sensors. Maximal distance of 1 mT (10 Gauss) field strength and 1 mT volume was calculated. Ex vivo measurements of the minimal safety distance (MSD) at which no mode switch can be observed between six representative CIEDs and the PEDs was performed. Results were compared to other PEDs, such as digital pens, headsets and their cases, and a Smartphone.

Result

Maximal 1 mT distances ranged between 10 mm and 19 mm, and 1 mT volumes between 6 cm3 and 19 cm3. The smartwatches and PEDs with measured 1 mT distance 15 mm (B: Microsoft surface pen, C: Airpods Pro case) showed device interaction up to > 15 mm (Figure). Linear regression analysis showed an inverse linear relationship of the MSD with 1 mT distance (B coefficient: 0.459; 95% CI: 0.246-0.672; p<0.001) but not with the volume (p=0.842)

Conclusions

Standardized measurements of the 1 mT field distance and volume is feasible and has the potential to assess the risk of CIED interaction. Smartwatches seem to be safe in contrast to other PEDs such as the Microsoft surface pen or Airpods Pro case with high 1mT volumes and maximal distances with regards to CIED interaction.

Are disparities of waiting times for breast cancer care related to socio-economic factors? A regional population-based study (France)

The increasing number of breast cancer cases may induce longer waiting times (WT), which can be a source of anxiety for patients and may play a role in survival. The aim of this study was to examine the factors, in particular socio-economic factors, related to treatment delays. Using French Cancer Registry databases and self-administered questionnaires, we included 1,152 women with invasive non-metastatic breast cancer diagnosed in 2007. Poisson regression analysis was used to identify WTs' influencing factors. For 973 women who had a malignant tissue sampling, the median of overall WT between the first imaging procedure and the first treatment was 44 days (9 days for pathological diagnostic WT and 31 days for treatment WT). The medical factors mostly explained inequalities in WTs. Socio-economic and behavioral factors had a limited impact on WTs except for social support which appeared to be a key point. Better identifying the factors associated with increase in WTs will make it possible to develop further interventional or prospective studies to confirm their causal role in delay and at last reduce disparities in breast cancer management.

Understanding receptivity to informal supportive cancer care in regional and rural Australia: a Heideggerian analysis

The concept of receptivity is a new way of understanding the personal and social factors that affect a person living with and beyond cancer, and how these factors influence access to formal supportive care service provision and planning. This article contributes to new knowledge through applying the concept of receptivity to informal supportive cancer care in regional Australia. Literature indicates that a cancer diagnosis is a life-changing experience, particularly in regional communities, where survival rates are lower and there are significant barriers to accessing services. Heideggerian phenomenology informed the design of the study and allowed for a rich and nuanced understanding of participants lived experiences of informal supportive cancer care. These experiences were captured using in-depth interviews, which were subsequently thematically analysed. Nineteen participants were recruited from across regional Victoria, Australia. Participants self-reported a range of stages and types of cancer. Significantly, findings revealed that most participants were not referred to, and did not seek, formal supportive care. Instead, they were receptive to informal supportive care. Understanding receptivity and the role of anxiety and fear of death has implications for partners, family, community members, as well as professionals working with people with living with and beyond cancer.

Do gender differences affect the doctor-patient interaction during consultations in general practice? Results from the INTERMEDE study

OBJECTIVE

The aim of the study was to ascertain whether disagreement between GPs and patients on advice given on nutrition, exercise and weight loss is related to patient-doctor gender discordance. Our hypothesis is that a patient interacting with a physician of the same gender may perceive more social proximity, notably on health care beliefs and may be more inclined to trust them.

METHODS

The analysis used the Intermede project's quantitative data collected via mirrored questionnaires at the end of the consultation. Multilevel logistic regressions were carried out to explore associations between patient-doctor gender discordance and their disagreement on advice given during the consultation adjusted on patients' and physicians' characteristics. The sample consists of 585 eligible patients and 27 GPs.

RESULTS

Disagreement on advice given on nutrition was observed less often for female concordant dyads: OR = 0.25 (95% CI = 0.08-0.78), and for female doctors-male patients dyads: OR = 0.24 (95% CI = 0.07-0.84), taking the male concordant dyads as reference. For advice given on exercise, disagreement was found less often for female concordant dyads OR = 0.38 (95% CI = 0.15-0.98) and an interdoctor effect was found (P < 0.05). For advice given on weight loss, the probability of disagreement was significantly increased (OR: 2.87 95% CI = 1.29-6.41) when consultations consisted of female patient and male GP.

CONCLUSION

Patient-doctor gender concordance/discordance is associated with their agreement/disagreement on advice given during the consultation. Physicians need to be conscious that their own demographic characteristics and perceptions might influence the quality of prevention counseling delivered to their patients.

Returning home: psychosocial care during the re-entry phase of cancer survivorship in rural Australia

The purpose of this research was to highlight gaps in formal psychosocial care for cancer survivors in rural communities. The study was conducted in rural Victoria, Australia, and involved interviews with people with various stages of cancer progression, cancer diagnoses and survival times, who were interviewed about their experiences of psychosocial cancer care. Interviews focused on their experience of psychosocial care and were audio-recorded and transcribed verbatim. Data were thematically analysed to identify key themes. Findings demonstrate that psychosocial care is essentially informal within the re-entry period after cancer diagnosis and treatment. Despite current Australian clinical guidelines on psychosocial care for people with cancer, which indicate the need for the provision of formal psychosocial care, participants in this study largely cared for themselves, or received informal support from family, friends and community members. Many psychosocial needs remained unmet and professional support was lacking. While this study was conducted in rural Australia, many of our findings have been echoed in studies from other countries. The findings have implications for treatment protocols and discharge planning, health professional-patient-family relationships, and the long-term well-being of cancer survivors living in rural communities. A model for understanding the experience of formal supportive care during the re-entry phase of survivorship is proposed.

Is perceived social distance between the patient and the general practitioner related to their disagreement on patient's health status?

OBJECTIVE

To ascertain whether disagreement between patients and general practitioners (GP) on the patient's health status varies according to their respective perceived social distance (PSD).

METHODS

The analysis used the Intermede project's quantitative data collected from 585 patients and 27 doctors via mirrored questionnaires. GPs and patients ranked their own perceived social position (PSP) in society, and their patients' and their GP respectively. PSD was calculated as the PSP's subtraction from the patients' and GPs' assessments.

RESULTS

Disagreement between GPs and patients regarding the patient's health status was associated with PSD by the GP whereas it was not associated with PSD by the patient. In the multilevel analysis, disagreement whereby GPs overestimate patient's health status increased within PSD by the GP: OR:2.9 (95%CI = 1.0-8.6, p = 0.055) for low PSD, OR:3.4 (95%CI = 1.1-10.2, p < 0.05) for moderate PSD and OR:3.8 (95%CI = 1.1-13.1, p < 0.05) for high PSD (reference: no distance).

CONCLUSIONS

Patients perceived with a lower social position by their GP and who consider themselves to have poor health are less likely to be identified in the primary care system.

PRACTICE IMPLICATIONS

Physicians need to be conscious that their own perception influences the quality of the interaction with their patients, potentially resulting in unequal health care trajectories.

Management of HSV-1 encephalitis due to reactivation of HSV-1 during late pregnancy

A previously healthy 31-year-old G4P2 woman at 33 weeks of gestation was admitted as an emergency with a pyrexia of 39°C, vomiting, headache and neck stiffness associated with photophobia, phonophobia and visual and auditory symptoms. There were no heraldic signs of eclampsia. Polymerase chain reaction and testing for herpes simplex virus in the cerebrospinal fluid diagnosed herpes simplex-1 meningoencephalitis. Following acyclovir, the clinical course improved. Spontaneous vaginal delivery occurred at 39 weeks of gestation with epidural analgesia using ropivacaine. Mother and child were neurologically normal and healthy 15 months later. Early administration of acyclovir is essential to reduce the risk of neurological complications. After treatment and a negative polymerase chain reaction for herpes simplex virus in the cerebrospinal fluid, epidural analgesia with local anesthetic and sufentanil is possible.

Do general practitioners overestimate the health of their patients with lower education?

This study sought to ascertain whether disagreement between patients and physicians on the patients' health status varies according to patients' education level. INTERMEDE is a cross-sectional multicentre study. Data were collected from both patients and doctors via pre- and post consultation questionnaires at the GP's office over a two-week period in October 2007 in 3 regions of France. The sample consists of 585 eligible patients (61% women) and 27 GPs. A significant association between agreement/disagreement between GP and patient on the patient's health status and patient's education level was observed: 75% of patients with a high education level agreed with their GP compared to 50% of patients with a low level of education. Patients and GPs disagreed where patients with the lowest education level said that their health was worse relative to their doctor's evaluation 37% of the time, versus 16% and 14% for those with a medium or high education level respectively. A multilevel multivariate analysis revealed that patients with a low educational level and medium educational level respectively were at higher risk of being overestimated by GP's in respect of self-reported health even if controlling for confounders. These findings suggest that people with a lower education level who consider themselves to have poor health are less reliably identified as such in the primary care system. This could potentially result in lack of advice and treatment for these patients and ultimately the maintenance of health inequalities.

[Application of "disease management" to the organization and compensation of professionals in the U.S.A., Germany and England: prospects for France]

Disease management, developed in the U.S.A. in the 1990s, is a comprehensive integrated approach that aims to incorporate all phases of chronic disease management from prevention to health education. Its main objective is to optimize patient care services by making patients more responsible for the management of their chronic disease. The specificity of its implementation in different countries is reflected by its translation into various concepts, such as: in the United States by the concept of the "Medical Home", in Germany by establishing contracts that encourage GPs and social security funds to support patients with chronic diseases, and in the United Kingdom through programs with measures that support the delegation of tasks and cooperation between primary care professionals. Disease management is accompanied by the introduction of new forms of payment for doctors and primary care facilities that ensure the effective implementation of the underpinning principles of disease management programs. In France, the development of the disease management approach is being promoted and advocated for integration into primary care, as it is gradually becoming an integral part of the French National Health Insurance Fund's strategy to enhance and improve the quality of care.

Patient-physician interaction in general practice and health inequalities in a multidisciplinary study: design, methods and feasibility in the French INTERMEDE study

Background

The way in which patients and their doctors interact is a potentially important factor in optimal communication during consultations as well as treatment, compliance and follow-up care. The aim of this multidisciplinary study is to use both qualitative and quantitative methods to explore the 'black box' that is the interaction between the two parties during a general practice consultation, and to identify factors therein that may contribute to producing health inequalities. This paper outlines the original multidisciplinary methodology used, and the feasibility of this type of study.

Methods and design

The study design combines methodologies on two separate samples in two phases. Firstly, a qualitative phase collected ethnographical and sociological data during consultation, followed by in-depth interviews with both patients and doctors independently. Secondly, a quantitative phase on a different sample of patients and physicians collected data via several questionnaires given to patients and doctors consisting of specific 'mirrored' questions asked post-consultation, as well as collecting information on patient and physician characteristics.

Discussion

The design and methodology used in this study were both successfully implemented, and readily accepted by doctors and patients alike. This type of multidisciplinary study shows great potential in providing further knowledge into the role of patient/physician interaction and its influence on maintaining or producing health inequalities. The next challenge in this study will be implementing the multidisciplinary approach during the data analysis.

Social vulnerability and unmet preventive care needs in outpatients of two French public hospitals

BACKGROUND

Outpatients attending consultations at public hospitals may have unmet needs for preventive medical care. This study aimed to identify and assess the association between these needs, social vulnerability and mode of healthcare use.

METHODS

In a multicentre epidemiological study, a group of socially vulnerable outpatients, was compared with a non-vulnerable group in a sample of 1316 outpatients selected in hospital consultations, using a validated tool for detection of social vulnerability. Before the patient was seen by medical staff, investigators collected data on social characteristics, healthcare use and preventive medical care received (interventions, advice).

RESULTS

More than 75% of outpatients stated that they were regularly followed by a physician, usually a general practitioner, but fewer vulnerable than non-vulnerable outpatients were followed (77% vs. 89%, P < 10(-3)). For the majority of preventive interventions (vaccinations, screening for cardiovascular risk factors, gynaecological cancers), vulnerable outpatients presented a more marked shortage than non-vulnerable patients, but there was an overall shortage in both groups. When recommended preventive interventions had not been delivered, they had rarely been offered in either group. After adjustment for mode of healthcare use, the differences in preventive care received persisted to the disadvantage of vulnerable outpatients with regard to technical preventive interventions, but there was no difference between the two groups regarding advice received to reduce risk behaviours.

CONCLUSION

Unmet needs for preventive care primarily resulted from social inequalities in secondary access to such care. It may be necessary to set up specific interventions targeting vulnerable patients within hospital consultations.

Effect of mandibular nerve block on postoperative analgesia in patients undergoing oropharyngeal carcinoma surgery under general anaesthesia

BACKGROUND

Postoperative analgesia after oropharyngeal carcinoma surgery remains poorly studied. This study investigates the effects of mandibular nerve block (MNB) with ropivacaine 10 mg ml(-1) in conjunction with general anaesthesia (GA) on postoperative analgesia after partial glossectomy or transmandibular lateral pharyngectomy.

METHODS

In a randomized double-blind study, 42 patients (21 in each group) received an MNB by the lateral extra-oral approach (MNB group) or a deep s.c. injection of normal saline (control group). Both groups received a standardized general anaesthetic. Postoperative analgesia included fixed dose of i.v. acetaminophen and morphine via a patient-controlled analgesia device. Consumption of morphine and supplemental analgesics and pain scores at rest were measured.

RESULTS

The mean cumulative morphine consumption was reduced by 56 and 45% at 12 and 24 h after operation in the MNB group. The administration of analgesic rescue medications was delayed in the MNB group. The visual analogue scale (VAS) pain scores were comparable in the two groups during the first 24 h. Adequate analgesia (mean VAS < or = 3) was observed throughout the study period in the MNB group, but only from 4 h after operation onwards in the control group. The number of patients who experienced severe pain (VAS > 7) during the first postoperative day was lower in the MNB group than in the control group (3 vs 10. respectively, P < 0.05).

CONCLUSIONS

In this study, MNB performed before GA for oropharyngeal carcinoma surgery improved postoperative analgesia, resulting in reduced morphine consumption at 24 h and severe pain in fewer patients.

Inégalités sociales de santé : quels impacts sur l’accès aux soins de prévention ?

En abordant la réduction des inégalités sociales et territoriales de santé sous l’angle exclusif de l’amélioration de l’accès aux soins des populations les plus « vulnérables », les politiques et programmes de santé considèrent une seule dimension de ces inégalités, alors qu’elles traversent l’ensemble de la hiérarchie sociale. Or, si les disparités d’accès aux soins préventifs ne constituent pas le déterminant principal des inégalités sociales de santé, dans un modèle de soins français essentiellement curatif, elles ne sont pas négligeables dans leur production. Cependant, les mesures visant à élargir l’accès aux soins de prévention ne sont pas les seules à mettre en oeuvre pour réduire les inégalités sociales de santé, qui traversent l’ensemble de la hiérarchie sociale.

Preoperative Peribulbar Block in Patients Undergoing Retinal Detachment Surgery Under General Anesthesia: A Randomized Double-Blind Study

Retinal detachment surgery is frequently associated with significant postoperative pain and emesis in adults. In this randomized, double-blind, controlled study we sought to demonstrate that 1% ropivacaine peribulbar (PB) block in conjunction with general anesthesia (GA) improves operative conditions and postoperative analgesia compared with GA combined with subcutaneous normal saline injection into the inferior eyelid. Thirty-one patients were included in each group. Anesthesia was performed with target-controlled infusion propofol and continuous remifentanil infusion adjusted to maintain bispectral index values between 40 and 50. Postoperative analgesia included fixed-dose IV infusion of propacetamol and IV injection of nefopam via a patient-controlled analgesia device. Tramadol was infused IV as rescue medication. Demographic data were comparable between the groups and bispectral index values were maintained at the objective target. In the PB group, fewer patients presented an oculocardiac reflex (6 versus 17; P < 0.01); bleeding interfering with the surgical field was reduced (1 versus 11 patients; P < 0.01); mean time to first nefopam request was longer (148 +/- 99 versus 46 +/- 58 min; P < 0.01); mean nefopam consumption was diminished during the first 6 h after tracheal extubation (18.9 +/- 13.9 versus 28.5 +/- 14.7 mg; P < 0.05); immediate postoperative pain scores were lower; and fewer patients required rescue medication (5 versus 23; P < 0.01). The two groups were similar with respect to the incidence of postoperative nausea and vomiting. Overall, PB block combined with GA improved operating conditions and postoperative analgesia in retinal detachment surgery.

Patient-controlled cervical epidural fentanyl compared with patient-controlled i.v. fentanyl for pain after pharyngolaryngeal surgery

BACKGROUND

Analgesia after pharyngolaryngeal surgery is commonly provided through the i.v. route. The aim of the study was to compare cervical epidural administration of fentanyl with the i.v. route for postoperative analgesia after pharyngolaryngeal surgery.

METHODS

In a randomized double-blind study 42 patients received fentanyl via patient-controlled analgesia (PCA) either through the i.v. route (PCA-IV group, n=22) or through the cervical epidural route (PCA-Epid group, n=20). Identical PCA settings were used in the two groups (bolus dose: 1.5 microg kg(-1), bolus: 25 microg, lockout interval: 10 min, maximum cumulative dose: 400 microg per 4 h). Analgesia at rest and during swallowing was evaluated using a visual analogue scale.

RESULTS

Analgesia at rest was better in the PCA-Epid group than in the PCA-IV group but only 2 and 6 h after surgery (P<0.02). There was no difference in analgesia during swallowing. Cumulative doses of fentanyl were similar {PCA-Epid group: 1412 microg (912), PCA-IV group: 1287 microg (1200) [median (IQR)]}. The Pa(o(2)) showed a significant decrease between the preoperative and postoperative period, but this decrease was identical in the two groups [PCA-IV-group: 11.47 (2.4) kPa vs 8.27 (0.9) kPa; PCA-Epid group: 11.33 (1.9) kPa vs 9.20 (2.4) kPa for preoperative and postoperative period respectively].

CONCLUSIONS

The study results show that cervical epidural analgesia provides marginally better pain relief at rest with no decrease in the fentanyl consumption. The use of the cervical epidural administration of fentanyl is questionable because of the possible complications of the technique.

[Epidemiological survey of a suspected nosocomial case of tuberculosis by spoligotyping]

Transmission of tuberculosis within hospitals has been increasingly recognized as a hazard for patients and health care workers. A case of pulmonary tuberculosis was detected in September 2003 in a nursing auxiliary working at Avicenne's Hospital. This 49 year-old woman was considered infected since April 2003. During this 6 months period, she worked in 23 distinct hospital units and could have contaminated patients and hospital staffs. The epidemiological survey was comprised for 1735 individuals (701 hospital staffs and 1034 patients). It encompassed clinical, para-clinical investigations and bacteriological investigations. Furthermore, between January 2003 and September 2004, a systematic comparison of 62 Mycobacterium tuberculosis strains isolated in the hospital was conducted by spoligotyping, a molecular typing method in order to access an eventual transmission. The nursing auxiliary's strain clearly showed a distinct spoligotype from the other investigated strains. This spoligotype was unique in the international spoligotype database. In this large epidemiological survey of a case of suspected nosocomial of tuberculosis, spoligotyping appeared as an interesting, easy and rapid method of molecular typing. It allowed to demonstrate that the nursing auxiliary tuberculosis case was unrelated to the others cases of tuberculosis diagnosed in the hospital during this period.

A Comparison of Target- and Manually Controlled Infusion Propofol and Etomidate/Desflurane Anesthesia in Elderly Patients Undergoing Hip Fracture Surgery

Elderly patients have a higher risk of developing adverse drug reactions during anesthesia, especially anesthesia affecting cardiovascular performance. In this prospective randomized study we compared quality of induction, hemodynamics, and recovery in elderly patients scheduled for hip fracture surgery and receiving either etomidate/desflurane (ETO/DES) or target-controlled (TCI) or manually controlled (MAN) propofol infusion for anesthesia. Sixteen patients were anesthetized with ETO (0.4 mg/kg) followed by DES titrated from an initial end-tidal concentration of 2.5%. Eighteen patients received propofol TCI at an initial plasma concentration of 1 microg/mL and titrated upwards by 0.5-microg/mL steps. Fifteen patients received a bolus induction of propofol 1 mg/kg over 60 s followed by an infusion initially set at 5 mg . kg(-1) . h(-1). All received a bolus (20 microg/kg) followed by an infusion of 0.4 microg . kg(-1) . min(-1) alfentanil. According to hemodynamics, concentrations of DES or propofol (TCI group) and propofol infusion rate (MAN group) were respectively adjusted by a step of 20% and 50%. In the TCI and ETO/DES groups, the time spent at a mean arterial blood pressure within 15% and 30% of baseline values was more than 60% and 80% of anesthesia time, whereas in the MAN group it was <30% and 60%, respectively. In the MAN group more anesthetic drug adjustments were recorded (6.4 +/- 2.8 versus 2.5 +/- 1.2 [ETO/DES] and 2.6 +/- 1 [TCI]). TCI improves the time course of propofol's hemodynamic effects in elderly patients.

Vulnérabilité socialedes consultants d'odontologie d'un hôpital public

There are social inequalities in oral and dental health. It can be useful to identify people in socially vulnerable or marginalised situations because they require a particular kind of care. Through a survey of patients in a dentistry services in a public hospital, we sought to identify those people in a precarious socio-economic situation by the use of a tool designed and validated by multi-disciplinary experts. The tool includes five criteria, and is presented in the format of an index card which is filled in by the patient upon his arrival. This data collection was carried out in two distinctly separate period of time (winter and summer). 865 cards were collected, and the rate of collection of complete data was 73%. 94% of the cards allowed us to determine the socio-economic status of the patient, and 48% (n=382) of them were classified as having a socially vulnerable situation. Among them, 69% of them benefited from CMU or AME, and 59% of them do not have any supplementary health insurance. 47% of them admit to having difficulties in paying for their medications or covering the cost of their medical consultations, and 48% perceive a social service aide. The prevalence of social vulnerability of the dental centre's patients is estimated at 32%. This data collection tool has made it possible to measure the significance and the nature of the social vulnerability of the patients who receive care and services from this public hospital's dentistry unit. Its capacity to identify patients whose care needs are often not met remains to be seen, as well as the capacity of the hospital to make up for these lost opportunities thus remains to be highlighted.

Élaboration d’un outil de repérage des usagers en situation de vulnérabilité sociale consultant à l’hôpital

OBJECTIVE

To develop and assess the metrological properties of a simple to use tool to identify socially vulnerable outpatients.

METHODS

A multidisciplinary group of professionals selected five characteristics identifying social vulnerability, integrated in a self-reported questionnaire, from which 5 criteria identify the socially vulnerable outpatients consulting the hospital. The metrological performance of the tool was assessed on a sample of randomly selected outpatients admitted to the emergency department and the results referred to the independent assessment of two social workers. The sensitivity and specificity of the tool were determined and ROC curves drawn.

RESULTS

222 patients were included, aged from 15 to 93 Years (mean: 53 Years), 59% of whom were men. 78% filled out the questionnaire on their own, while 22% required help, usually for physical or material reasons and 87% answered the five questions without any difficulty. The kappa coefficient of agreement between the two social workers was estimated at 0.94 (CI: 0.89-0.98). The sensitivity of the self reported questionnaire was of 70% (CI: 64-76) and its specificity of 77% (CI: 71-82). The ROC curves showed that the modified tool had a sensitivity of 80% (Sp: 67%). With only 2 characteristics, this sensitivity was of 76% (Sp: 73%).

CONCLUSION

This tool, which is based on the advice of various experts, is valid and presents acceptable metrological properties. Once some simplifications have been made, the questionnaire could be used in routine in any patient consulting the hospital because it is acceptable, simple to use and can be rapidly filled-in.

[Facial anesthetic blocks in the treatment of acute pain during ophthalmic zoster]

BACKGROUND

Ophthalmic zoster is frequently accompanied by severe pain in the frontal and nasal divisions of the ophthalmic nerve. Treating this pain is often difficult, particularly in elderly patients, owing to iatrogenic effects and to interactions with the pre-existing diseases and treatments frequently present in this age group. The aim of our study was to consider the efficacy and toxicity of the frontal and nasal nerve blocks in the treatment of severe pain during acute ophthalmic zoster in the elderly.

MATERIAL AND METHODS

A prospective study was conducted on 20 patients (mean age, 76 +/-7 years; range, 63-88) presenting with acute ophthalmic zoster with severe pain (less than 1 month since onset), which had resisted analgesic medication. All patients had a visual analogue score for pain (VAS) of 4 or more and received one or more anesthetic blocks of a compound of bupivacaine with adrenaline associated with clonidine at the frontal branch and sometimes the nasal branch levels of the ophthalmic nerve. Pain was measured daily by VAS for 5 days, and the blocks were repeated if the VAS was still 4 or higher. Patients were checked for local or systemic side effects.

RESULTS

The number of anesthetic blocks per patient ranged from one to four (mean: 2.3 +/-0.7). All patients experienced less pain after the first injection. The mean preinjection VAS was 7.4 +/-1 and fell to 4.8 +/-1.0, 4.1 +/-1.1, 3.5 +/-1.0, 3.2 +/-0.6 and 2.8 +/-0.9 at day 1, day 2, day 3, day 4 and day 5, respectively (p<0.001). It was possible to reduce analgesic medication permanently in all patients. No local or systemic side effect was observed.

CONCLUSION

Anesthetic blocks of the frontal and nasal branches, repeated if necessary, give fast and effective relief from the severe pain of acute ophthalmic zoster. They are fully tolerated and simple to administer, making them an excellent indication in the complementary treatment of the pain of hyperalgic acute zoster in the elderly.

Target-controlled versus manually-controlled infusion of propofol for direct laryngoscopy and bronchoscopy

Few studies have compared the clinical profile of target-controlled infusions of propofol with that of manually-controlled infusions. Fifty-four ASA physical status I or II patients scheduled for an elective otorhinolaryngology endoscopy performed under general anesthesia with spontaneous ventilation were enrolled in this prospective randomized study to compare the clinical outcome of such administrations. Before induction, all patients received a single alfentanil bolus dose (10 microg/kg). Propofol administration was adapted to maintain absence of movement, hemodynamic stability, and efficient spontaneous ventilation. When compared with the Manually-Controlled Infusion group, in the Target-Controlled Infusion group there were fewer movements at insertion of the laryngoscope (14.8% vs. 44.4%), improved hemodynamic stability (largest variations of mean arterial blood pressure <10% of control values, versus 20%), fewer episodes of apnea, and less respiratory acidosis after endoscopy (pH = 7.37 +/- 0.05 and PaCO(2) = 50 +/- 7 mm Hg versus pH = 7.28 +/- 0.06 and PaCO(2) = 58 +/- 9 mm Hg); the recovery was also shorter (time to opening eyes or verbal response, 4.6 +/- 2.0 min and 6.8 +/- 2.5 min versus 10.8 +/- 7.3 min and 15.7 +/- 7.1 min). Propofol consumption was comparable in the two groups. Targeting the effect-site concentration improved the time course of the propofol drug effect during direct laryngoscopy performed during spontaneous ventilation when compared with manual infusion.

IMPLICATIONS

This study compares the clinical profile of propofol anesthesia for direct laryngoscopy with spontaneous ventilation when the drug is administered either as a manually controlled infusion or by targeting the effect-site concentration through a target-controlled infusion (TCI) device. TCI improves the time course of propofol effects.

[Critical analysis of health priorities determination in France]

Since the mid 1970's, reforms to the health care system were aimed at controlling expenditures. Furthermore, there was not much of a relationship between public health policies and expenditure control policies. The reforms of 1996 aimed to introduce a new paradigm. The French health care system, based until then upon the biomedical model, now must adopt public health tools: Definition of health objectives; Development of priorities; Evaluation; Allocation of resources based on needs; Public debates. The objective of this study is to evaluate the move toward defining priorities, three years after the introduction of this reform. The study focused on the type of priorities implemented (e.g. implicit or explicit priorities, access to health care services, or severity of health problems) and their links to the allocation of resources; and the practical development of priorities (e.g. political or technocratic procedure, the role of public debates). In France, priorities are defined by health problem and not by service. They are explicit, but the link to allocation of resources isn't clear. Despite a wide consultation, the system of defining priorities is more technocratic than political. Moreover, the system is more concerned with including health professionals (doctors, administrators) in this new approach to public health, than with taking public opinion into account.

[The definition of acoustic impedance and its application to the human hearing organ]

Acoustic impedance measurement at the point of entry into the external auditory meatus provides a rapid means to detect malfunctions of the middle ear in the region of the tympanic membrane, without having recourse to perforating the tympanic membrane. In this article we define acoustic impedance and provide a brief reminder of its physical properties. In the last part, we review the possibilities offered by measurement of the impedance to acoustic stimuli, not only for clinical diagnosis, but also in the understanding ot the physical phenomena occurring within the hearing organ.

[Difficulties with the implementation and institutional stakes in the continuing education of private physicians]

The Formation Medical Continue (FMC) is a continuing education programme for private practice doctors (generalists and specialists), and was established in the legislation of April 1996. In analysing the stages of the policy's introduction, an attempt was made to understand the difficulties encountered in its implementation. Using a semi-directive questionnaire, the opinions concerning the policy were collected from the different actors in the process: professionals, social welfare organisations, government agencies and health organisations. The analysis of their perceptions was complemented by an analysis of historical data and a review of the literature. The greatest difficulties with implementation related to the interactions among the stakeholders: the "game" of the medical unions, among themselves and with social security and government agencies; the under-representation of the medical profession, exacerbated by its divisions and the split between generalists and specialists; the indecision of government agencies, leaving the stakeholders waiting; the "game" of the social security funds, which act as if the principle of "mutualisation" of FMC funds can be by-passed. Conflicts of interest regarding the FMC have "crystallised" among the different stakeholders, as well as within the medical corpus. These conflicts relate in particular to the creation of the memorandum agreement and to the definition of the relationship with the pharmaceutical industry.

Minimal peptide length requirements for CD4(+) T cell clones--implications for molecular mimicry and T cell survival

CD4(+) T lymphocytes usually recognize peptides of 12-16 amino acids in the context of HLA class II molecules. We have recently used synthetic peptide combinatorial libraries to dissect in detail antigen recognition by autoreactive CD4(+) T cell clones (TCC). The results of these studies demonstrated that antigen recognition by T cells is highly degenerate and that many cross-reactive ligands can be defined, some of which much more potent than the selecting autoantigen. Based on these observations, we examined the response of a myelin basic protein-specific HLA class II-restricted CD4(+) TCC to truncation variants of optimal ligands. Surprisingly, pentapeptides, tetrapeptides and even tripeptides derived from different segments of the optimal ligands were recognized by the TCC, and some were even more potent than the selecting autoantigen. In addition, these peptides enhanced the survival of the TCC at low concentration. The relevance of this finding was supported by the generation of pentapeptide-specific CD4(+) TCC from peripheral blood lymphocytes. These observations not only change existing views on the length requirements for activation of CD4(+) HLA class II-restricted T cells, but also extend our knowledge about the flexibility of TCR recognition and the potential for cross-reactivity in the immune system.

Identification of candidate T-cell epitopes and molecular mimics in chronic Lyme disease

Elucidating the cellular immune response to infectious agents is a prerequisite for understanding disease pathogenesis and designing effective vaccines. In the identification of microbial T-cell epitopes, the availability of purified or recombinant bacterial proteins has been a chief limiting factor. In chronic infectious diseases such as Lyme disease, immune-mediated damage may add to the effects of direct infection by means of molecular mimicry to tissue autoantigens. Here, we describe a new method to effectively identify both microbial epitopes and candidate autoantigens. The approach combines data acquisition by positional scanning peptide combinatorial libraries and biometric data analysis by generation of scoring matrices. In a patient with chronic neuroborreliosis, we show that this strategy leads to the identification of potentially relevant T-cell targets derived from both Borrelia burgdorferi and the host. We also found that the antigen specificity of a single T-cell clone can be degenerate and yet the clone can preferentially recognize different peptides derived from the same organism, thus demonstrating that flexibility in T-cell recognition does not preclude specificity. This approach has potential applications in the identification of ligands in infectious diseases, tumors and autoimmune diseases.

Preferential expansion of autoreactive T lymphocytes from the memory T-cell pool by IL-7

We have developed a new technique that allows us to quantify antigen-specific T cells, and to determine their functional phenotype and origin from naive versus memory populations. Using this methodology, we have characterized a total of 286 T-cell lines specific for myelin basic protein (MBP) and influenza hemagglutinin from 16 multiple sclerosis (MS) patients and nine healthy donors. Our data support the notion that MBP-specific T cells undergo in vivo activation in MS patients and indicate a presence of immune dysregulation that renders MS patients prone to develop autoimmunity. Our methodology offers a way to study antigen-specific T-cell characteristics as a surrogate marker in immunotherapy trials.

The use of soluble synthetic peptide combinatorial libraries to determine antigen recognition of T cells

T cells identify by their T-cell receptor (TCR) short peptides in the context of major histocompatibility complex (MHC) molecules. The interaction of the trimolecular complex composed of the TCR and MHC bound peptide was extensively studied using substitution analogs of the original peptide ligands to define those residues important for T-cell recognition in the peptide chain. This approach has led to the observation that T-cell recognition is highly flexible and that many different peptides can be recognized by an individual TCR. Others and we have recently introduced synthetic peptide combinatorial libraries (SCL) to investigate T-cell recognition. Here we review the SCL-based approaches and describe our current techniques for mapping TCR motifs for CD4+ T cells. The implications of our findings for the understanding of T-cell recognition, as well as for future applications to study T-cell responses in infectious diseases, autoimmune disorders and cancer are discussed.

Environment- and sequence-dependent modulation of the double-stranded to single-stranded conformational transition of gramicidin A in membranes

The role of the membrane lipid composition and the individual Trp residues in the conformational rearrangement of gramicidin A along the folding pathway to its channel conformation has been examined in phospholipid bilayers by means of previously described size-exclusion high-performance liquid chromatography HPLC-based strategy (Bañó et al. (1991) Biochemistry 30, 886). It has been demonstrated that the chemical composition of the membrane influences the transition rate of the peptide rearrangement from double-stranded dimers to beta-helical monomers. The chemical modification of Trp residues, or its substitution by the more hydrophobic residues phenylalanine or naphthylalanine, stabilized the double-stranded dimer conformation in model membranes. This effect was more notable as the number of Trp-substituted residues increased (tetra > tri > di > mono), and it was also influenced by the specific position of the substituted amino acid residue in the sequence, in the order Trp-9 approximately Trp-13 > Trp-11 > Trp-15. Moreover, it was verified that nearly a full contingent of indoles (Trp-13, -11, and -9) is necessary to induce a quantitative conversion from double-stranded dimers to single-stranded monomers, although Trp-9 and Trp-13 seemed to be key residues for the stabilization of the beta-helical monomeric conformation of gramicidin A. The conformation adopted for monomeric Trp --> Phe substitution analogues in lipid vesicles resulted in CD spectra similar to the typical single-stranded beta6.3-helical conformation of gramicidin A. However, the Trp --> Phe substitution analogues showed decreased antibiotic activity as the number of Trp decreased.

Linear and nonlinear model of the human middle ear

The measurement of the middle ear transfer function usually requires invasive methods. An equivalent analog equivalent model enables us to evaluate its characteristics without damaging any part of the ear. A linear and a nonlinear model of the middle ear have been developed to predict intracochlear pressure and the stapes volume velocity for various sound pressure levels (SPL). The linear model results have been compared with human eardrum impedance and middle ear transfer function data. The nonlinear phenomena due to the contraction of the stapedius muscle over 80 dB and to the stapes clipping displacement above 120 dB are represented by a set of variable electrical components. The model of the acoustic reflex is based on experimental observations. The study of the annular ligament behavior was performed on cats and extrapolated to humans with some hypothetical restrictions. These approximations provide information on the middle ear transfer function and enable us to better understand the nonlinear middle ear mechanisms in an intense acoustic field.