Chloral hydrate warning

The alternative of oral sedation for pediatric dental care

In pediatric dentistry, chloral hydrate is habitually selected for sedation of uncooperative children. Although chloral hydrate has been used for decades, various adverse effects are reported and necessity for new alternative drugs has increased. Dexmedetomidine was approved by FDA for sedation at intensive care units (ICU) in 1999. Compared to conventional sedative drugs, dexmedetomidine has not only analgesic and sedative effects but also it barely suppresses the respiratory system. Due to these characteristics, dexmedetomidine is known as safe sedative drug for children and elderly patients. Furthermore, approved by KFDA in 2010 in Korea, the frequency of sedation using dexmedetomidine is increasing. However, due to its intravenous administration method, it was difficult to apply in pediatric dentistry. Recently, intranasal administration method was introduced which might be a new possible alternative of oral sedation.

In this study, we compare the mechanisms, pros and cons of chloral hydrate and dexmedetomidine, introducing new possibilities.

Short-Term Chloral Hydrate Administration and Cancer in Humans

OBJECTIVE

Chloral hydrate, used as a hypnosedative in adults and children, has been shown to be genotoxic and carcinogenic in animal studies. We investigated the potential causal association between chloral hydrate exposure and cancer risk in humans.

METHODS

Cancer incidence was previously determined via biennial screening analyses of the 215 most commonly used drugs between 1976 and 1998 for a cohort of 143,574 outpatients at Kaiser Permanente who had prescriptions filled between 1969 and 1973. Among users of chloral hydrate, statistically significant elevations in standardised morbidity ratios were observed during various years for cancer at five anatomical sites, including the lung, stomach, prostate, skin melanoma and mouth floor. In this analysis, these associations were investigated using: (i) a dose-response analysis among exposed subjects; and (ii) a two-stage design with exposed and non-exposed persons.

RESULTS

There was evidence of an increasing risk of prostate cancer with increasing number of dispensings of chloral hydrate, which persisted after controlling for benign prostatic hypertrophy, vasectomy and obesity; however, the trend was not statistically significant. There was no evidence of a dose-response relationship between chloral hydrate and risk of any of the other four cancers. In the two-stage design, analyses comparing exposed and unexposed subjects showed no increased risk of cancer after controlling for confounding variables; however, the data were suggestive for prostate cancer, where the increased risk associated with chloral hydrate exposure after adjustment for confounding variables persisted. No dose-response relationship was seen for any of the other four cancer sites.

CONCLUSIONS

To our knowledge, this is the first study to examine the relationship between chloral hydrate exposure and cancer risk in humans. There was no persuasive evidence to support a causal relationship between chloral hydrate exposure in humans and the development of cancer. However, statistical power was low for weak associations, particularly for some of the individual cancer sites. Although animal data using much higher doses of chloral hydrate have demonstrated its genotoxicity and carcinogenicity, the effects of chloral hydrate in humans are still uncertain.

Dietary controlled carcinogenicity study of chloral hydrate in male B6C3F1 mice

Chloral hydrate, which is used as a sedative in pediatric medicine and is a by-product of water chlorination, is hepatocarcinogenic in B6C3F1 mice, a strain that can exhibit high rates of background liver tumor incidence, which are associated with increased body weight. In this study, dietary control was used to manipulate body growth in male B6C3F1 mice in a 2-year bioassay of chloral hydrate. Male B6C3F1 mice were treated with water or 25, 50, or 100 mg/kg chloral hydrate by gavage. The study compared ad libitum-fed mice with dietary controlled mice. The latter received variably restricted feed allocations to maintain their body weights on a predetermined "idealized" weight curve predictive of a terminal background liver tumor incidence of 15-20%. These mice exhibited less individual body weight variation than did their ad libitum-fed counterparts. This was associated with a decreased variation in liver to body weight ratios, which allowed the demonstration of a statistically significant dose response to chloral hydrate in the dietary controlled, but not the ad libitum-fed, test groups. Chloral hydrate increased terminally adjusted liver tumor incidence in both dietary controlled (23.4, 23.9, 29.7, and 38.6% for the four dose groups, respectively) and ad libitum-fed mice (33.4, 52.6, 50.6, and 46.2%), but a statistically significant dose response was observed only in the dietary controlled mice. This dose response positively correlated with markers of peroxisomal proliferation in the dietary controlled mice only. The study suggests that dietary control not only improves terminal survival and decreases interassay variation, but also can increase assay sensitivity by decreasing intra-assay variation.

Sedation/Analgesia for diagnostic and therapeutic procedures in children

Sedation/analgesia for diagnostic and therapeutic procedures in children has been associated with life-threatening adverse events. Reports of adverse events and recognition of wide variability in sedation practices has led to the development of guidelines and standards of care to ensure the safety of sedated children. The safety of sedated children can be enhanced by detailed presedation evaluation, careful patient selection, and the use of drugs with a wide margin of safety that are carefully titrated to desired depth of sedation by trained personnel. Once sedative drugs are administered, stringent monitoring, including continuous pulse oximetry and frequent assessment of vital signs and sedation depth, will permit early recognition of untoward drug effects and permit early intervention. Children with underlying medical conditions, such as airway abnormalities, may not be suitable subjects for sedation and may require consideration for general anesthesia to aid their procedure. Although significant strides have been made in recognition of the risks of sedation and in development of guidelinesfor safe sedation practices, further work must focus on development of newer sedation regimens with shorter-acting drugs and wider margins of safety.

Safe Pediatric Outpatient Sedation: The Chloral Hydrate Debate Revisited

Diagnostic imaging in the pediatric patient frequently requires sedation. The use of chloral hydrate, the standard agent for many years, has recently come under severe scrutiny. The American Academy of Pediatrics (AAP) published guidelines for the elective sedation of pediatric patients; however, compliance with the AAP guidelines is not compulsory. A review of the medical literature shows a wide range of medications used for pediatric sedation, along with a diversity in the protocols available for monitoring the cardiopulmonary status of the patient. When ordering computed tomography and magnetic resonance imaging scans, pediatric otolaryngologists indirectly are exposing their patients to the sedation practices and monitoring protocols of their referral imaging center. A questionnaire regarding the sedation protocol for routine, outpatient, computed tomography or magnetic resonance imaging scans in children aged 5 years or younger was sent to staff radiologists at 36 pediatric medical centers throughout the United States. A variety of sedation practices were elicited. The complete survey results are presented, including monitoring practices, complication, and success rates. Despite concerns about its safety, chloral hydrate remains a frequently used and safe method of pediatric outpatient sedation.

Potential carcinogenicity of chloral hydrate--a review

Chloral hydrate is commonly used to sedate children for diagnostic or therapeutic procedures. The drug has been extensively used for many years, but there are remarkably few data on its long-term health effects. Concern in this regard is raised by recent studies showing chloral hydrate to be genotoxic, causing chromosome changes and other effects in vivo and in vitro. In addition, chloral hydrate is a reactive metabolite of trichloroethylene, a known carcinogen, and is structurally similar to other carcinogenic intermediates. Two carcinogenicity studies performed using the oral route of administration in mice indicate that the drug is potentially carcinogenic--in one case after a single dose lower than the typical dose used for sedation. Practitioners should be aware of chloral hydrate's genotoxicity and potential carcinogenicity. Discretion in its use seems appropriate until further studies clarify its long term health consequences.

Oral chloral hydrate provides effective and safe sedation in paediatric magnetic resonance imaging

Sedation is routinely required for successful Magnetic Resonance imaging in infants and children. Five hundred and ninety-six paediatric patients (270 female and 326 male, age (mean +/- SD) 41 +/- 30 months and weight 14.8 +/- 6.5 kg) entered an open, non-comparative, prospective study to assess oral chloral hydrate sedation in a large and homogeneous paediatric population undergoing Magnetic Resonance imaging. Chloral hydrate syrup 70 mg/ml was administered 20-40 min prior to the procedure. Effective sedation was reached in 94.1% with a total dose (mean +/- SEM) of 68 +/- 1 mg/kg (range 20-170 mg/kg). Statistical analysis of sedation failures vs. successful examinations after the total dose showed significant differences for dose (62 +/- 4 vs. 69 +/- 1 mg/kg; P < 0.05), age (64 +/- 7 vs. 40 +/- 1 months; P < 0.001) and weight (19.8 +/- 1.5 vs. 14.5 +/- 0.0 kg; P < 0.001). Effectiveness fell to around 80% in children with encephalic white matter alterations, medullary tumours or syringohydromyela (P = 0.07). The mean time of onset of sedation was 26 +/- 1 min, and the mean time to spontaneous awakening after the completion of the Magnetic Resonance examination was 38 +/- 2 min. Fifty-nine children (9.9%) experienced adverse reactions, with nausea and vomiting being the most common (n = 41), followed by nervousness and unusual excitement (n = 6). Discriminant function analysis identified age and total dose as the quantitative variables helping to differentiate between sedation failures and satisfactory examinations (sensitivity = 0.73, and specificity = 0.61; r = 0.20, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Anesthesia for MRI examination]

Magnetic resonance imaging (MRI) requires the patients to stay for 30-45 min in a magnetic closed noisy space. Therefore most children and agitated adults require general anaesthesia or sedation in order to high quality images. Anaesthesia may be given by several routes (TIVA, inhalational or intrarectal administration) using common drugs. However, the magnetic field limits the selection of patients undergoing MRI and the spectrum of anaesthetic and monitoring equipment. The magnetic field may have deleterious effects on implanted ferromagnetic devices. It may attract objects towards the magnet centre at a dangerous speed. Moreover it may disturb the function of monitors and anaesthesia machines which should be tested for a specific magnetic field strength before introducing their use in a given MRI unit.

Dentists, drugs, and decisions: introduction to Part I--Therapeutic drugs

Numerous dental therapeutic agents or drugs are available over the counter or with prescription for patient use at home or in a professional office. Knowledge of the processes by which these agents are evaluated for safety and efficacy by the FDA and ADA is necessary for dental professionals to make intelligent decisions concerning their use. Several examples of problems with drug/cosmetic evaluations are cited.

Sedation in Neonatal and Pediatric Intensive Care

Despite the widespread use of potent sedative and analgesic agents in adult patients, it is remarkable that systemic analgesia and sedation have not been administered routinely to neonates and children until very recently. Adequate sedation and analgesia have historically been withheld from these patients because of the mistaken beliefs that pain perception was not fully developed and that these patients were much more prone to adverse effects of the most commonly used agents. There is now overwhelming evidence that pain perception and physiologic responses to stress are present in neonates of all gestational ages and a variety of effective sedative/analgesic agents have recently been added to the therapeutic armamentarium. We will outline the classes of agents currently available, briefly describe mechanisms of action and the relevant pharmacokinetic—pharmacodynamic parameters, summarize the short-term and long-term side effects following prolonged administration of these agents, and highlight practical considerations for the most commonly used sedative-analgesic medications.