Search PubMed⌕ Search

Biomedical subjects

Gideon Koren

Publications and source records attributed to Gideon Koren.

At least 109 records · Page 6Linked to original sources
PubMed2005

A critical review of the topical local anesthetic amethocaine (Ametop) for pediatric pain.

A topical formulation of the ester-type local anesthetic amethocaine (tetracaine) [Ametop ] is currently available for reducing pain from cutaneous procedures such as venipuncture. The Ametop mark preparation contains 40 mg of amethocaine base (4% w/w) and produces anesthesia within 30-45 minutes of application; duration of action ranges from 4 to 6 hours. Clinical studies have demonstrated the superiority of the 4% amethocaine preparation over placebo in pediatric populations for indications such as intravenous cannulation, vaccination, and venipuncture. Amethocaine has been shown to produce anesthesia comparable to that of 5% lidocaine-prilocaine for procedures such as venipuncture and accessing centrally placed devices; in general, anesthesia was achieved more rapidly with amethocaine than lidocaine-prilocaine. In the neonatal population amethocaine was found to be ineffective at reducing the pain of heel prick and peripherally inserted central catheters. Depending on the type of procedure, amethocaine application times between 30 and 60 minutes have produced clinically acceptable anesthesia; application times <30 minutes have not been associated with reliable anesthesia. The 4% amethocaine preparation is well tolerated; the most commonly reported local skin reaction is transient local erythema while local edema and itching have been reported more rarely. There have been no accounts of systemic toxicity with topical use of the preparation. Several cases of sensitization have been described in adults upon repeated exposure to topical amethocaine. In summary, the novel preparation of 4% amethocaine gel has been shown to be clinically effective for managing pain associated with minor cutaneous procedures while maintaining a good tolerability profile. Amethocaine has also demonstrated similar efficacy to lidocaine-prilocaine when appropriate application times are used; the more rapid onset of action and extended duration of action of amethocaine may make it more useful than lidocaine-prilocaine in busy clinical settings.

Adolescent↗
PubMed2005

Toxicokinetics of mercury elimination by succimer in twin toddlers.

We describe the toxicokinetics of mercury in two twin toddlers poisoned by an East Indian remedy for teething. Succimer (dimercaprosuccinic acid, DMSA) decreased the plasma elimination half-life of mercury by 3-fold in the patient with high exposure; a more modest effect was observed in the other twin. Succimer is a chelation agent used in the treatment of heavy metal intoxication. A water-soluble agent, it increases the urinary excretion of lead and mercury. The drug is rapidly but variably absorbed through the gastrointestinal tract, with peak levels occurring at 1-2 hours. After its absorption, peak mercury excretion through the urine occurs within 2-4 hours. In the poisoned twin sisters, succimer administration led to a mercury plasma elimination half-life of 6 weeks. Although succimer has been used in mercury poisoning in adults and children, the toxicokinetics of mercury have not previously been characterized in either age group. We believe this is the first such description. More studies on the toxicokinetics and dynamics of mercury chelation with succimer in young children are needed to ensure the optimal use of the drug in this population.

Antidotes↗
PubMed2005

Transfer of glyburide and glipizide into breast milk.

OBJECTIVE: To determine if glyburide and glipizide are excreted into breast milk and if breast-feeding from women taking these drugs causes infant hypoglycemia. RESEARCH DESIGN AND METHODS: We studied eight women who had received a single oral dose of 5 or 10 mg glyburide. Drug concentrations were measured in maternal blood and milk for 8 h after the dose. In a separate study, five women were given a daily dosage (5 mg/day) of glyburide or glipizide, starting on the first postpartum day. Maternal blood and milk drug concentrations and infant blood glucose were measured 5-16 days after delivery. RESULTS: In the single-dose glyburide study, the mean maximum theoretical infant dose (MTID) as a percent of the weight-adjusted maternal dose (WAMD) was <1.5 and <0.7% for the 5- and 10-mg doses, respectively. For the five women taking daily dosages, the mean MTID as a percent of the WAMD was <28% for glyburide and <27% for glipizide. The high estimates were due to the insensitivity of the assay. Neither glyburide nor glipizide were detected in breast milk in either study and blood glucose was normal in the three infants (one glyburide and two glipizide) who were wholly breast-fed when the drug concentrations were at steady state. CONCLUSIONS: Neither glyburide nor glipizide were detected in breast milk, and hypoglycemia was not observed in the three nursing infants. Both agents, at the doses tested, appear to be compatible with breast-feeding.

Adult↗
PubMed2005

Pregnancy outcome of women using atypical antipsychotic drugs: a prospective comparative study.

BACKGROUND: A substantial number of women of childbearing age suffer from schizophrenia and other mental illnesses that require the use of antipsychotic drugs. Atypical antipsychotics have been on the market since the mid-1990s, and to date there are no prospective comparative studies regarding use during pregnancy. OBJECTIVES: (1) To determine whether atypical antipsychotics increase the rate of major malformations above the 1% to 3% baseline risk seen in the general population. (2) To examine rates of spontaneous and therapeutic abortions, rates of stillbirths, birth weight, and gestational age at birth. METHOD: The cohort was composed of pregnant women who contacted the Motherisk Program in Canada or the Israeli Teratogen Information Service in Israel and women who were recruited from the Drug Safety Research Unit database in England. Women who had been exposed to atypical antipsychotics were matched to a comparison group of pregnant women who had not been exposed to these agents. RESULTS: Data were obtained on 151 pregnancy outcomes that included exposure to olanzapine (N= 60), risperidone (N = 49), quetiapine (N = 36), and clozapine (N = 6). Among women exposed to an atypical antipsychotic, there were 110 live births (72.8%), 22 spontaneous abortions (14.5%), 15 therapeutic abortions (9.9%), and 4 stillbirths (2.6%). Among babies of women in this group, there was 1 major malformation (0.9%), and the mean +/-SD birth weight was 3341 +/-685 g. There were no statistically significant differences in any of the pregnancy outcomes of interest between the exposed and comparison groups, with the exceptions of the rate of low birth weight, which was 10% in exposed babies compared with 2% in the comparison group (p = .05), and the rate of therapeutic abortions (p = .003). CONCLUSION: These results suggest that atypical antipsychotics do not appear to be associated with an increased risk for major malformations.

Abnormalities, Drug-Induced↗
PubMed2005

Screening for fetal alcohol spectrum disorder.

QUESTION: I have several patients whom I suspect are drinking during pregnancy. How can I find out for sure if they are? ANSWER: You can use one of the validated tools to screen for problem drinking. Motherisk uses the TWEAK test, but others are just as good. Following birth, you can test infants' meconium for metabolites of ethanol to detect whether they were exposed in utero to excessive drinking.

Alcoholism↗
PubMed2005

Low-molecular-weight heparins during pregnancy.

QUESTION: A few years ago I suffered from pulmonary emboli. My physician recommended I use dalteparin during this pregnancy although, during my previous pregnancy, I had received subcutaneous heparin injections three times daily. Is dalteparin the same as heparin? ANSWER: : Based on the best available evidence from mostly small prospective case series, retrospective reports, and placental perfusion studies, low-molecular-weight heparins (LMWHs), such as dalteparin, are a safe and convenient alternative to heparin during pregnancy for both mothers and fetuses.

Anticoagulants↗
PubMed2005

Marijuana use and breastfeeding.

QUESTION: One of my breastfeeding patients is using marijuana to combat chronic pain. Is it safe for her to breastfeed? ANSWER: Lactating mothers should refrain from consuming cannabinoids. Advising mothers to discontinue breastfeeding if they cannot stop using cannabinoids must incorporate the known risks of formula feeding. Cannabinoid exposure through milk has not been shown to increase neonatal risk, but there are no appropriate studies of this. In every case, nursing babies should be closely monitored.

Analgesics, Non-Narcotic↗
PubMed2005

Pregnant "DES daughters" and their offspring.

QUESTION: I am a 34-year-old woman in my second trimester of pregnancy. My mother took diethylstilbestrol when she was pregnant with me. Could my expected child be affected by this? ANSWER: Animal studies suggest the child could be affected, but little data on humans strongly support this. You could plan to have your child monitored for a potential, though unlikely, effect.

Adult↗
PubMed2005

Tumour necrosis factor alpha and use of infliximab. Safety during pregnancy.

QUESTION: A 27-year-old patient of mine with rheumatoid arthritis has been treated with infliximab for the last 5 years. She is planning her first pregnancy. How should I advise her regarding use of infliximab during pregnancy, bearing in mind that infliximab substantially improved her medical condition? ANSWER: Infliximab (Remicade) has not been tested in pregnant animals because it does not interact with non-human tumour necrosis factor (TNF) alpha. Several case reports describing women who used infliximab during pregnancy do not suggest a strong association with adverse pregnancy outcomes. More studies are required to determine infliximab's safety during pregnancy.

Abnormalities, Drug-Induced↗
PubMed2005

Pregnancy after stem cell transplantation.

QUESTION: A married woman under my care underwent successful bone marrow transplantation as part of treatment for a malignancy. She wishes to start a family. What are her chances? Are there risks? ANSWER: Success in becoming pregnant after stem cell transplantation depends on such factors as cumulative doses of chemotherapy and radiation and mother's age at time of transplant. There is increased risk of prematurity, low birth weight, and spontaneous abortion. Pregnancy should be managed as high risk.

Female↗
PubMed2005

Nonsteroidal anti-inflammatory drugs for rheumatoid arthritis during pregnancy.

QUESTION: I am treating two pregnant patients who have rheumatoid arthritis with nonsteroidal anti-inflammatory drugs. Are these medications safe at high doses during pregnancy? ANSWER: While these medications do not appear to increase overall rates of congenital malformations, they do increase the risk of ductus arteriosus constriction or closure.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2005

Taking antidepressants during late pregnancy. How should we advise women?

QUESTION: In light of recent negative media attention to antidepressant use during late pregnancy, several of my patients have either discontinued or are considering discontinuing their antidepressant medications. How can I best counsel these patients on taking antidepressants during late pregnancy? ANSWER: Antidepressant use during the third trimester has been associated occasionally with a transient neonatal withdrawal-like syndrome characterized by jitteriness, self-limiting respiratory difficulties, and problems with feeding. When counseling patients, the risk of these adverse effects must be weighed against the risks associated with untreated depression during late pregnancy. Abrupt discontinuation of psychotropic medications has been associated with both physical (eg, withdrawal) and psychological (eg, suicidal thoughts) symptoms.

Antidepressive Agents↗
PubMed2005

[Infectious complications with herpes virus after ritual Jewish circumcision: a historical and cultural analysis].

Ritual circumcision performed on eight-day-old male infants is rooted in the Bible and is discussed in the earliest Jewish sources. The practice has been observed across the generations in every Jewish community in Israel and the Diaspora. According to Jewish ritual, the mohel--the ritual circumcisor--amputates the foreskin and then folds back the membrane that lies beneath it. This is followed by metzitza--"suction"--a practice performed throughout the ages by mouth. Halakhic literature sets down strict rules regarding this surgical intervention in order to prevent medical complications for the newborn. Metzitza by mouth has been recognized as a risk factor in the transfer of infection from the mohel to the newborn. A recent study relates to eight infants who became infected with herpes virus as a result of the procedure. We shall review the halakhic literature in order to clarify the custom of metzitza by mouth and understand the principles underlying the controversy that surrounds it. The custom of metzitza by mouth has been the subject of extensive rabbinic discussion since the middle of the nineteenth century. A better understanding of the historical, social and cultural background of the issue might allow us to formulate alternatives to the practice. The metzitza controversy gave rise to a stimulating discussion in the rabbinic literature with diverse and conflicting opinions. We shall undertake a precise analysis of the rabbinic discussion and its historical and social background, and attempt to identify the ideological underpinnings of the various positions. Rabbinic literature is replete with cautionary measures to be observed when circumcising a newborn child. The halakhic disputes beginning in the middle of the nineteenth century reflect ideological considerations and objectives. Metzitza was performed throughout the generations by mouth because that was the recognized method of disinfection at the time. Beginning in the nineteenth century, medical and esthetic considerations have led to the abolishment of metzitza by mouth or to its performance by way of a swab or through a glass tube in order to prevent infection. Ideological tendentiousness is evident in both approaches: Should the medical risks of metzitza by mouth be overlooked and denied out of loyalty to ancient tradition, thus allowing the practice to be continued? Or should the recognition of such risks along with esthetic considerations lead to changes in halakhic thinking to perform the metzitza in a hygienic technique? Historically, the issue of metzitza by mouth has been a bone of contention between traditional outlook and modern halakhic thinking, which takes into consideration advances in medical knowledge. In light of the reports in the medical literature about complications in the wake of metzitza by mouth, some of the halakhic rulings regarding circumcision should be reconsidered. Clinically, it is important to raise the medical community's awareness of the phenomenon and treat infected infants accordingly.

Circumcision, Male↗
PubMed2004

Assessing nicotine metabolism in pregnancy--a novel approach using hair analysis.

Nicotine and its metabolite cotinine are important biochemical markers to determine active or passive exposure to cigarette smoke. The amount of nicotine and cotinine in hair provides a cumulative index of tobacco exposure. This study uses segmental hair analysis to assess changes in nicotine metabolism in a cohort of pregnant women who smoked steadily during the whole gestational period according to their self-report. Maternal hair was collected at the time of delivery and sectioned into segments representing the three trimesters of pregnancy. The concentrations of nicotine and cotinine in each section of hair were measured by radioimmunoassay. Hair concentration of nicotine decreased during pregnancy without any reported reduction in smoking, while the cotinine concentration remained constant. The nicotine-cotinine ratio in these consistent smokers was: 1st trimester 20.6, 2nd trimester 19.9, and 3rd trimester 13.3. These findings are consistent with results from other studies showing increased nicotine metabolism during pregnancy. Our data suggest that the results of segmental hair analysis should be carefully examined in pregnancy. Both nicotine and cotinine levels should be evaluated in order to confirm any significant change in maternal tobacco exposure during pregnancy.

Cohort Studies↗
PubMed2004

Prospective observational study on the incidence of medication errors during simulated resuscitation in a paediatric emergency department.

OBJECTIVES: To characterise the incidence and nature of medication errors during paediatric resuscitations. DESIGN: A prospective observational study of simulated emergencies. SETTING: Emergency department of a tertiary paediatric hospital. PARTICIPANTS: Teams that included a clinician who commonly leads "real" resuscitations, at least two assisting physicians, and two or three paediatric nurses. INTERVENTIONS: The teams conducted eight mock resuscitations, including ordering medications. Exercises were videotaped and drugs ordered and administered during the resuscitation were recorded. Syringes and drugs prepared during the resuscitation were collected and analysed for concentrations and actual amounts. MAIN OUTCOME MEASURES: Number and type of drug errors. RESULTS: Participants gave 125 orders for medications. In 21 (17%) of the orders the exact dose was not specified. Nine dosing errors occurred during the ordering phase. Of these errors, five were intercepted before the drug reached the patient. Four 10-fold errors were identified. In nine (16%) out of 58 syringes analysed, measured drug concentrations showed a deviation of at least 20% from the ordered dose. A large deviation (at least 50%) from the expected dose was found in four (7%) cases. CONCLUSIONS: Medication errors commonly occur during all stages of paediatric resuscitation. Many errors could be detected only by analysing syringe content, suggesting that such errors may be a major source of morbidity and mortality in resuscitated children.

Child↗
PubMed2004

Pregnancy outcome following rubella vaccination: a prospective controlled study.

The rubella virus is a potent human teratogen. Because the rubella vaccine is prepared with live virus, a high level of anxiety surrounds exposure in pregnancy. There is relatively scarce data on fetal risk following vaccination in pregnancy, and all of the available data were collected retrospectively. Our objective was to examine whether periconceptional exposure to rubella vaccine can cause the congenital rubella syndrome, and to compare the rate of major malformations and developmental milestones among offspring of women who received rubella vaccine 3 months pre- or post-conception to an unexposed comparison group. We collected prospectively and followed up 94 women who received rubella vaccination 3 months pre- or post-conception and a comparison group that consisted of 94 women who were counseled during pregnancy in a similar manner but were not exposed to known teratogens. The controls were matched for age, smoking, alcohol, and drug use. Not any of the women exposed to the vaccine gave birth to a child with congenital rubella syndrome. Rates of major malformations were similar in both groups as were birth weights and developmental milestones. In contrast, the rate of therapeutic abortions was higher in the exposed group (7.4% vs. 0%) (P < 0.05), due to fears of teratogenicity. We conclude that rubella vaccination in pregnancy does not appear to affect pregnancy outcome in general or cause congenital rubella syndrome in particular.

Abortion, Therapeutic↗