Efficacy and safety of chloral hydrate in auditory brainstem response test: A systematic review and single-arm meta-analysis

OBJECTIVES

To evaluate the safety and efficacy of chloral hydrate in auditory brainstem response (ABR) tests.

SETTING AND DESIGN

In this study, the authors systematically searched both English (Embase, PubMed, and Web of Science) and Chinese (Chinese National Knowledge Infrastructure, Wanfang Data, and VIP Chinese Science) databases. Two authors independently performed data extraction and quality assessment. The pooled sedation failure rate and the pooled incidence of adverse events were calculated via a random-effects model. Sensitivity and subgroup analyses were performed to explore the sources of heterogeneity, and the PRISMA guideline was followed.

PARTICIPANTS

Patients with ABR tests receiving chloral hydrate sedation.

MAIN OUTCOME MEASURES

The pooled sedation failure rate and the pooled incidence of adverse events.

RESULTS

A total of 23 clinical studies were included in the final analysis. The pooled sedation failure rate of patients who received chloral hydrate sedation before ABR examination was 10.0% [95% confidence interval (CI) (6.7%, 15.0%), I2 = 95%, p < .01]. There were significant differences in the prevalence of sedation failure between sample sizes greater than 200 and those less than or equal to 200 (5.6% vs. 19.6%, p < .01) and between the studies that reported sleep deprivation and those that did not report sleep deprivation (7.1% vs. 18.9%, p < .01). The pooled incidence of adverse events was 10.32% [95% CI (5.83%, 14.82%), I2 = 98.1%, p < .01].

CONCLUSIONS

Chloral hydrate has a high rate of sedation failure, adverse events, and potential carcinogenicity. Therefore, replacing its use in ABR tests with safer and more effective sedatives is warranted.

Dynamic effects of miR-20a-5p on hippocampal ripple energy after status epilepticus in rats

To determine the dynamic effects of miR-20a-5p on hippocampal ripple energy in rats after status epilepticus (SE). A lithium pilocarpine (LiCl-PILO)-induced rat model of status epilepticus (SE) was established, and the rats were divided into the normal control (Control, CTL), epileptic control (PILO), valproic acid (VPA + PILO), miR-20a-5p overexpression lentivirus vector (miR + PILO), sponges blocking lentivirus vector (Sponges + PILO), and scramble sequence negative control (Scramble + PILO) groups (n = 6). Electroencephalograms (EEGs) were used to analyze changes in hippocampal ripple energy before and after SE. Quantitative polymerase chain reaction (q-PCR) analysis showed that miR-20a-5p levels gradually increased after miR-20a-5p overexpression lentivirus vector injection into the lateral ventricle, and the miR-20a-5p levels were significantly higher than that in CTL group on days 7 and 36 (P < 0.001). The miR-20a-5p levels decreased significantly on days 7 and 36 after blocking by sponges lentivirus vector injected into the lateral ventricle (P < 0.001). After injection of PILO, the average ripple energy expression in each group gradually increased, and reached the peak before chloral hydrate injection (compared with 1 day before SE, P < 0.05). The ripple energy in the VPA + PILO and Sponges + PILO groups was significantly lower than that in the PILO group at 60 min and 70 min after PILO injection and before chloral hydrate injection (P < 0.05), and maintained lower until 2 h after chloral hydrate injection in VPA + PILO (P < 0.05). Compared with the VPA + PILO group, the mean ripple energy of the Sponges + PILO group had no difference at all time points (P ≥ 0.05). After SE, ripple distribution of space and energy is closely related to the occurrence of epilepsy. Inhibition of miR20a-5p expression can downregulate ripple oscillation energy during seizure.

French survey of sedation practices for pediatric magnetic resonance and computed tomography imaging

BACKGROUND

Pediatric magnetic resonance imaging (MRI) and computed tompgraphy (CT) require patient immobility and therefore often require sedation or general anesthesia of patients. Consensus on these procedures is lacking in France.

OBJECTIVE

Thus, the aim of this study was to describe the current sedation practices for pediatric MRI and CT in France.

MATERIAL AND METHODS

From January 2019 to December 2019, an online questionnaire was delivered by electronic mail to a representative radiologist in 60 pediatric radiology centers registered by the French-speaking pediatric and prenatal imaging society. Questions included protocols, drugs used, monitoring and side effects.

RESULTS

Representatives of 40 of the 60 (67%) radiology centers responded to the survey. Among them, 31 performed sedation including 17 (55%) centers where radiologists performed sedation without anesthesiologists present during the procedure. The premedication drugs were hydroxyzine (n = 8, 80%) and melatonin (n = 2, 20%), Sedation drugs used for children ages 0 to 6 years old were pentobarbital (n = 9, 60%), midazolam (n = 2, 13%), chloral hydrate (n = 2, 13%), diazepam (n = 1, 6.5%) and chlorpromazine (n = 1, 6.5%). A written sedation protocol was available in 10/17 (59%) centers. In 6/17 (35%) centers, no monitoring was used during the procedures. Blood pressure monitoring and capnography were rarely used (< 10%) and post-sedation monitoring was heterogeneous. No life-threatening adverse effect was reported, but 6 centers reported at least one incident per year.

CONCLUSION

For half of the responding radiology centers, radiologists performed sedation alone in agreement with the local anesthesiology team. Sedation procedures and monitoring were heterogenous among centers. Adjustment and harmonization of the practices according to the capacity of each center may be useful.

Safety and efficacy of pediatric sedation protocol for diagnostic examination in a pediatric emergency room: A retrospective study

Pediatric patients undergoing diagnostic tests in the pediatric emergency room are frequently sedated. Although efforts are made to prevent adverse events, no sedation protocol has specified the optimal regimen, dosage, and interval of medication to prevent adverse events. This study analyzed the safety and efficacy of sequential pediatric sedation protocols for pediatric patients undergoing diagnostic tests in the pediatric emergency room of a single tertiary medical center. The medical records of patients aged < 18 years who visited the pediatric emergency room of Seoul Asan Medical Center between January and December 2019 for diagnostic testing were retrospectively reviewed. Sedation protocols consisted of 50 mg/kg and 25 mg/kg chloral hydrate, 0.1 mg/kg and 0.1 mg/kg midazolam, and 1 mg/kg and 0.5 to 1 mg/kg ketamine, administered sequentially at intervals of 30, 20, 10, 10, and 10 minutes, respectively. Patients were assessed prior to sedation, and adverse events were investigated. Of the 289 included patients, 20 (6.9%) experienced adverse events, none serious, and nine (3.1%) failed to reach the depth of sedation required to complete the test. The regimen (P = .622) and dosage (P = .777) of the sedatives were unrelated to the occurrence of adverse events when sedation was performed according to protocol. The sedation protocol used in these patients, consisting of sequential administration of minimum dosages, achieved a sufficient depth of sedation with relatively few adverse events, indicating that this protocol can be used safely and effectively for painless sedation in pediatric patients undergoing diagnostic testing.

Use of a single dose of 70mg/kg chloral hydrate as a hypnotic in nuclear magnetic resonance. A prospective study of 3132 cases

OBJECTIVE

To assess the mean time to hypnosis, hemodynamic stability, and incidence of complications associated with the administration of 70mg/kg oral chloral hydrate in children scheduled for magnetic resonance imaging (MRI).

MATERIAL AND METHODS

Prospective study conducted from January 2000 to January 2020 in which 3132 patients aged between one day and 5 years underwent MRI under anaesthesia in an outpatient setting. The study population was divided into 4 subgroups: A) aged between one and 30 days; B) aged between one month and one year; C) aged between one and 3 years, and D) aged between 3 and 5 years. Study variables were: sex, age, type of examination, mean imaging time, mean time to awakening, heart rate before and after MRI, SatO₂, and incidence of complications such as respiratory depression (SatO₂ below 90%), agitation during the MRI or on awakening (intense crying lasting more than 2min), prolonged sedation measured on the Steward scale, and nausea and/or vomiting during the MRI, on awakening, or at home.

RESULTS

No notable hemodynamic alterations were observed. The incidence of desaturation was .41%, awakening during the test was .16%, prolonged sedation was 1.08%, and agitated awakening was 1.46%. Nausea and vomiting at the end of the test had an incidence of .73%. The P value in all cases was <.05%.

CONCLUSIONS

Chloral hydrate at a dose of 70mg/kg continues to be suitable in sedation lasting no more than one hour for non-invasive procedures in children, and is associated with adequate haemodynamic stability with practically no side effects.

Chloral hydrate as a sedating agent for neurodiagnostic procedures in children

BACKGROUND

This is an updated version of a Cochrane Review published in 2017. Paediatric neurodiagnostic investigations, including brain neuroimaging and electroencephalography (EEG), play an important role in the assessment of neurodevelopmental disorders. The use of an appropriate sedative agent is important to ensure the successful completion of the neurodiagnostic procedures, particularly in children, who are usually unable to remain still throughout the procedure.

OBJECTIVES

To assess the effectiveness and adverse effects of chloral hydrate as a sedative agent for non-invasive neurodiagnostic procedures in children.

SEARCH METHODS

We searched the following databases on 14 May 2020, with no language restrictions: the Cochrane Register of Studies (CRS Web) and MEDLINE (Ovid, 1946 to 12 May 2020). CRS Web includes randomised or quasi-randomised controlled trials from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform, the Cochrane Central Register of Controlled Trials (CENTRAL), and the specialised registers of Cochrane Review Groups including Cochrane Epilepsy.

SELECTION CRITERIA

Randomised controlled trials that assessed chloral hydrate agent against other sedative agent(s), non-drug agent(s), or placebo.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated studies identified by the search for their eligibility, extracted data, and assessed risk of bias. Results were expressed in terms of risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data, with 95% confidence intervals (CIs).

MAIN RESULTS

We included 16 studies with a total of 2922 children. The methodological quality of the included studies was mixed. Blinding of the participants and personnel was not achieved in most of the included studies, and three of the 16 studies were at high risk of bias for selective reporting. Evaluation of the efficacy of the sedative agents was also underpowered, with all the comparisons performed in small studies. Fewer children who received oral chloral hydrate had sedation failure compared with oral promethazine (RR 0.11, 95% CI 0.01 to 0.82; 1 study; moderate-certainty evidence). More children who received oral chloral hydrate had sedation failure after one dose compared to intravenous pentobarbital (RR 4.33, 95% CI 1.35 to 13.89; 1 study; low-certainty evidence), but there was no clear difference after two doses (RR 3.00, 95% CI 0.33 to 27.46; 1 study; very low-certainty evidence). Children with oral chloral hydrate had more sedation failure compared with rectal sodium thiopental (RR 1.33, 95% CI 0.60 to 2.96; 1 study; moderate-certainty evidence) and music therapy (RR 17.00, 95% CI 2.37 to 122.14; 1 study; very low-certainty evidence). Sedation failure rates were similar between groups for comparisons with oral dexmedetomidine, oral hydroxyzine hydrochloride, oral midazolam and oral clonidine. Children who received oral chloral hydrate had a shorter time to adequate sedation compared with those who received oral dexmedetomidine (MD -3.86, 95% CI -5.12 to -2.6; 1 study), oral hydroxyzine hydrochloride (MD -7.5, 95% CI -7.85 to -7.15; 1 study), oral promethazine (MD -12.11, 95% CI -18.48 to -5.74; 1 study) (moderate-certainty evidence for three aforementioned outcomes), rectal midazolam (MD -95.70, 95% CI -114.51 to -76.89; 1 study), and oral clonidine (MD -37.48, 95% CI -55.97 to -18.99; 1 study) (low-certainty evidence for two aforementioned outcomes). However, children with oral chloral hydrate took longer to achieve adequate sedation when compared with intravenous pentobarbital (MD 19, 95% CI 16.61 to 21.39; 1 study; low-certainty evidence), intranasal midazolam (MD 12.83, 95% CI 7.22 to 18.44; 1 study; moderate-certainty evidence), and intranasal dexmedetomidine (MD 2.80, 95% CI 0.77 to 4.83; 1 study, moderate-certainty evidence). Children who received oral chloral hydrate appeared significantly less likely to complete neurodiagnostic procedure with child awakening when compared with rectal sodium thiopental (RR 0.95, 95% CI 0.83 to 1.09; 1 study; moderate-certainty evidence). Chloral hydrate was associated with a higher risk of the following adverse events: desaturation versus rectal sodium thiopental (RR 5.00, 95% 0.24 to 102.30; 1 study), unsteadiness versus intranasal dexmedetomidine (MD 10.21, 95% CI 0.58 to 178.52; 1 study), vomiting versus intranasal dexmedetomidine (MD 10.59, 95% CI 0.61 to 185.45; 1 study) (low-certainty evidence for aforementioned three outcomes), and crying during administration of sedation versus intranasal dexmedetomidine (MD 1.39, 95% CI 1.08 to 1.80; 1 study, moderate-certainty evidence). Chloral hydrate was associated with a lower risk of the following: diarrhoea compared with rectal sodium thiopental (RR 0.04, 95% CI 0.00 to 0.72; 1 study), lower mean diastolic blood pressure compared with sodium thiopental (MD 7.40, 95% CI 5.11 to 9.69; 1 study), drowsiness compared with oral clonidine (RR 0.44, 95% CI 0.30 to 0.64; 1 study), vertigo compared with oral clonidine (RR 0.15, 95% CI 0.01 to 2.79; 1 study) (moderate-certainty evidence for aforementioned four outcomes), and bradycardia compared with intranasal dexmedetomidine (MD 0.17, 95% CI 0.05 to 0.59; 1 study; high-certainty evidence). No other adverse events were significantly associated with chloral hydrate, although there was an increased risk of combined adverse events overall (RR 7.66, 95% CI 1.78 to 32.91; 1 study; low-certainty evidence).

AUTHORS' CONCLUSIONS

The certainty of evidence for the comparisons of oral chloral hydrate against several other methods of sedation was variable. Oral chloral hydrate appears to have a lower sedation failure rate when compared with oral promethazine. Sedation failure was similar between groups for other comparisons such as oral dexmedetomidine, oral hydroxyzine hydrochloride, and oral midazolam. Oral chloral hydrate had a higher sedation failure rate when compared with intravenous pentobarbital, rectal sodium thiopental, and music therapy. Chloral hydrate appeared to be associated with higher rates of adverse events than intranasal dexmedetomidine. However, the evidence for the outcomes for oral chloral hydrate versus intravenous pentobarbital, rectal sodium thiopental, intranasal dexmedetomidine, and music therapy was mostly of low certainty, therefore the findings should be interpreted with caution. Further research should determine the effects of oral chloral hydrate on major clinical outcomes such as successful completion of procedures, requirements for an additional sedative agent, and degree of sedation measured using validated scales, which were rarely assessed in the studies included in this review. The safety profile of chloral hydrate should be studied further, especially for major adverse effects such as oxygen desaturation.

Intranasal dexmedetomidine versus oral chloral hydrate for diagnostic procedures sedation in infants and toddlers: A systematic review and meta-analysis

BACKGROUND

Intranasal dexmedetomidine is a relatively new way to sedate young children undergoing nonpainful diagnostic procedures. We performed a meta-analysis to compare the efficacy and safety of intranasal dexmedetomidine in young children with those of oral chloral hydrate, which has been a commonly used method for decades.

METHODS

We searched PubMed, Embase, and the Cochrane Library for all randomized controlled trials that compared intranasal dexmedetomidine with oral chloral hydrate in children undergoing diagnostic procedures. Data on success rate of sedation, onset time, recovery time, and adverse effects were extracted and respectively analyzed.

RESULTS

Five studies with a total of 720 patients met the inclusion criteria. Intranasal dexmedetomidine provided significant higher success rate of sedation (relative risk [RR], 1.12; 95% confidence interval [CI], 1.02 to 1.24; P = .02; I = 74%) than oral chloral hydrate. Furthermore, it experienced significantly shorter onset time (weight mean difference [WMD], -1.79; 95% CI, -3.23 to -0.34; P = .02; I = 69%). Nevertheless, there were no statistically differences in recovery time (WMD, -10.53; 95% CI, -24.17 to 3.11; P = .13; I = 92%) and the proportion of patients back to normal activities (RR, 1.11; 95% CI, 0.77-1.60; P = .57; I = 0%). Intranasal dexmedetomidine was associated with a significantly lower incidence of nausea and vomiting (RR, 0.05; 95% CI, 0.01-0.22; P < .0001; I = 0%) than oral chloral hydrate. Although adverse events such as bradycardia, hypotension and hypoxia were not synthetized due to lack of data, no clinical interventions except oxygen supplementation were required in any patients.

CONCLUSION

Our meta-analysis revealed that intranasal dexmedetomidine is possibly a more effective and acceptable sedation method for infants and toddlers undergoing diagnostic procedures than oral chloral hydrate. Additionally, it shows similar safety profile and could be a potential alternative to oral chloral hydrate.

Cardiorespiratory parameters in newborns during sedation with chloral hydrate

We commonly use chloral hydrate sedation in newborns, though its cardiorespiratory side effects have not yet been fully investigated. Our study aimed to analyze the impact of chloral hydrate on cardiorespiratory parameters in term newborns. We performed a prospective, pre-post single-arm interventional study in 42 term, respiratorily and hemodynamically stable newborns. Oxygen saturation (SpO2), end-tidal CO2 (ETCO2), the apnea-hypopnea index and the respiratory and heart rates were recorded by polygraphy, starting 0.5-1 hour before oral administration of chloral hydrate at a dose of 40 mg/kg and ceasing 4 hours post-administration. After administration of chloral hydrate, the mean basal SpO2 dropped by 2.0% (from 97.1% to 95.1%; p < 0.001) and the mean basal ETCO2 increased by 3.9 mmHg (25.6 to 29.5 mmHg; p < 0.001). We found a significant decrease in the minimal SpO2 values (p < 0.001) and an increase in the percentage of time spent with SpO2 < 95% and < 90% (p < 0.001). The mean increase in the estimated apnea-hypopnea index was 3.5 events per hour (p < 0.001). The mean respiratory and heart rates were significantly lower 150 min after the administration of chloral hydrate when compared with pre-sedation values (51/min and 127/min versus 61/min and 138/min respectively; p < 0.001). A considerable number of patients exhibited changes in cardiorespiratory parameters that differed considerably from the normal ranges. In conclusion, SpO2, ETCO2, the estimated apnea-hypopnea index and the respiratory and heart rates changed after the administration of chloral hydrate. They remained within normal limits in most newborns, but the inter-individual variability was high in the studied population.

Chloral Hydrate Administered by a Dedicated Sedation Service Can Be Used Safely and Effectively for Pediatric Ophthalmic Examination

PURPOSE

To determine safety and efficacy of oral chloral hydrate sedation (CHS) for outpatient pediatric ophthalmic procedures.

DESIGN

Prospective, interventional case series.

METHODS

Setting: King Khaled Eye Specialist Hospital.

SUBJECTS

Children aged 1 month to 5 years undergoing CHS for ocular imaging/evaluation.

PROCEDURES

Details on chloral hydrate dose administered, sedation achieved, vital signs, and adverse events were recorded.

OUTCOME MEASURES

Primary outcome was percentage of patients with a sedation level ≥ 4 at 45 minutes post chloral hydrate administration. Secondary outcomes were time from sedation to discharge and adverse events, including changes in vital signs following chloral hydrate administration.

RESULTS

A total of 324 children were recruited with a mean age of 2.2 (SD: 1.3) years and mean weight of 10.9 (SD: 3.3) kg. Adequate sedation was obtained with a mean chloral hydrate first dose of 77.4 (SD: 14.7) mg/kg in 306 (94.4%) patients, with an additional 6 patients (1.9%) achieving adequate sedation with a second dose (overall adequate sedation: 96.3%). Mean reductions in heart rate, respiratory rate, and oxygen (O₂) saturation from pre-sedation to 25 minutes post-sedation were 11.7 (SD: 14.3) beats per minute, 1.2 (SD: 2.4) breaths per minute, and 0.81% (SD: 1.2%), respectively (P < .001 for all). In multivariable regression, odds of remaining sedated 45 minutes after chloral hydrate administration were 2.53 times higher for American Society of Anesthesiologists (ASA) class II or III patients than for ASA class I (95% confidence interval [CI]: 1.11-5.78, P = .03), 1.03 times higher per mg increase in initial dose of chloral hydrate (95% CI: 1.01-1.06, P = .006), and 2.70 times higher per unit increase in number of planned procedures (95% CI: 1.63-4.47, P < .001). Three patients developed minor adverse events: 2 cases of O₂ desaturation and 1 paradoxical reaction, none requiring significant intervention. Patients were discharged a median of 90 minutes after chloral hydrate administration.

CONCLUSION

Chloral hydrate administered by a dedicated sedation service, as in this prospective assessment, can be used safely and effectively for outpatient pediatric ophthalmic procedures.

Chloral hydrate as a sedating agent for neurodiagnostic procedures in children

BACKGROUND

Paediatric neurodiagnostic investigations, including brain neuroimaging and electroencephalography (EEG), play an important role in the assessment of neurodevelopmental disorders. The use of an appropriate sedative agent is important to ensure the successful completion of the neurodiagnostic procedures, particularly in children, who are usually unable to remain still throughout the procedure.

OBJECTIVES

To assess the effectiveness and adverse effects of chloral hydrate as a sedative agent for non-invasive neurodiagnostic procedures in children.

SEARCH METHODS

We used the standard search strategy of the Cochrane Epilepsy Group. We searched MEDLINE (OVID SP) (1950 to July 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, Issue 7, 2017), Embase (1980 to July 2017), and the Cochrane Epilepsy Group Specialized Register (via CENTRAL) using a combination of keywords and MeSH headings.

SELECTION CRITERIA

We included randomised controlled trials that assessed chloral hydrate agent against other sedative agent(s), non-drug agent(s), or placebo for children undergoing non-invasive neurodiagnostic procedures.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the studies for their eligibility, extracted data, and assessed risk of bias. Results were expressed in terms of risk ratio (RR) for dichotomous data, mean difference (MD) for continuous data, with 95% confidence intervals (CIs).

MAIN RESULTS

We included 13 studies with a total of 2390 children. The studies were all conducted in hospitals that provided neurodiagnostic services. Most studies assessed the proportion of sedation failure during the neurodiagnostic procedure, time for adequate sedation, and potential adverse effects associated with the sedative agent.The methodological quality of the included studies was mixed, as reflected by a wide variation in their 'Risk of bias' profiles. Blinding of the participants and personnel was not achieved in most of the included studies, and three of the 13 studies had high risk of bias for selective reporting. Evaluation of the efficacy of the sedative agents was also underpowered, with all the comparisons performed in single small studies.Children who received oral chloral hydrate had lower sedation failure when compared with oral promethazine (RR 0.11, 95% CI 0.01 to 0.82; 1 study, moderate-quality evidence). Children who received oral chloral hydrate had a higher risk of sedation failure after one dose compared to those who received intravenous pentobarbital (RR 4.33, 95% CI 1.35 to 13.89; 1 study, low-quality evidence), but after two doses there was no evidence of a significant difference between the two groups (RR 3.00, 95% CI 0.33 to 27.46; 1 study, very low-quality evidence). Children who received oral chloral hydrate appeared to have more sedation failure when compared with music therapy, but the quality of evidence was very low for this outcome (RR 17.00, 95% CI 2.37 to 122.14; 1 study). Sedation failure rates were similar between oral chloral hydrate, oral dexmedetomidine, oral hydroxyzine hydrochloride, and oral midazolam.Children who received oral chloral hydrate had a shorter time to achieve adequate sedation when compared with those who received oral dexmedetomidine (MD -3.86, 95% CI -5.12 to -2.6; 1 study, moderate-quality evidence), oral hydroxyzine hydrochloride (MD -7.5, 95% CI -7.85 to -7.15; 1 study, moderate-quality evidence), oral promethazine (MD -12.11, 95% CI -18.48 to -5.74; 1 study, moderate-quality evidence), and rectal midazolam (MD -95.70, 95% CI -114.51 to -76.89; 1 study). However, children with oral chloral hydrate took longer to achieve adequate sedation when compared with intravenous pentobarbital (MD 19, 95% CI 16.61 to 21.39; 1 study, low-quality evidence) and intranasal midazolam (MD 12.83, 95% CI 7.22 to 18.44; 1 study, moderate-quality evidence).No data were available to assess the proportion of children with successful completion of neurodiagnostic procedure without interruption by the child awakening. Most trials did not assess adequate sedation as measured by specific validated scales, except in the comparison of chloral hydrate versus intranasal midazolam and oral promethazine.Compared to dexmedetomidine, chloral hydrate was associated with a higher risk of nausea and vomiting (RR 12.04 95% CI 1.58 to 91.96). No other adverse events were significantly associated with chloral hydrate (including behavioural change, oxygen desaturation) although there was an increased risk of adverse events overall (RR 7.66, 95% CI 1.78 to 32.91; 1 study, low-quality evidence).

AUTHORS' CONCLUSIONS

The quality of evidence for the comparisons of oral chloral hydrate against several other methods of sedation was very variable. Oral chloral hydrate appears to have a lower sedation failure rate when compared with oral promethazine for children undergoing paediatric neurodiagnostic procedures. The sedation failure was similar for other comparisons such as oral dexmedetomidine, oral hydroxyzine hydrochloride, and oral midazolam. When compared with intravenous pentobarbital and music therapy, oral chloral hydrate had a higher sedation failure rate. However, it must be noted that the evidence for the outcomes for the comparisons of oral chloral hydrate against intravenous pentobarbital and music therapy was of very low to low quality, therefore the corresponding findings should be interpreted with caution.Further research should determine the effects of oral chloral hydrate on major clinical outcomes such as successful completion of procedures, requirements for additional sedative agent, and degree of sedation measured using validated scales, which were rarely assessed in the studies included in this review. The safety profile of chloral hydrate should be studied further, especially the risk of major adverse effects such as bradycardia, hypotension, and oxygen desaturation.

Effects of Surgical Anaesthesia on the Viability of Nigral Grafts in the Rat Striatum

Only a small proportion of dopamine neurons in nigral grafts typically survive transplantation into the adult striatum. Since many anaesthetics reduce blood flow and disturb a variety of brain metabolites, surgical anaesthesia may be one of the factors that compromise graft survival. Conversely, the lowered core body temperature induced by some anaesthetics might promote the survival of grafted cells by slowing their metabolism. In an initial screen, the widely-used surgical anaesthetic, equithesin, was found to reduce core temperature, mean arterial blood pressure, and to increase the partial pressure of oxygen in arterial blood without producing any significant alteration in arterial pH or the partial pressure of carbon dioxide. In the main experiment, rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal bundle received dopamine-rich embryonic nigral grafts injected into the deafferented neostriatum via previously implanted guide cannulae, which allowed comparison to be made of graft survival after transplantation into awake and in re-anaesthetised animals. There were no significant differences between groups in either the functional effects of the grafts to compensate amphetamine-induced rotation, or in the survival and growth of the grafts as measured in post mortem histology. We therefore conclude that anaesthesia per se is not a major contributory factor in the relatively poor survival of dopamine neurons following transplantation into the rat striatum.

Safety and Efficacy of Chloral Hydrate Sedation in Paediatric Sedation for Ophthalmic Procedures

INTRODUCTION

Chloral hydrate (CH) sedation is routinely used in paediatric ophthalmic examination in Singapore as an alternative to examination under general anaesthesia. Despite CH's traditionally high success rates and relatively low rate of adverse events, there is little data on its safety and efficacy as a sedative for ophthalmic procedures in an Asian population.

MATERIALS AND METHODS

A retrospective chart review was performed, including children who underwent CH sedation at the Singapore National Eye Centre from January 2012 to January 2015. Participants were given an initial dose of CH and a top-up dose if required. Univariate and multivariate analyses were performed on data collected.

RESULTS

CH sedation was successful in 144 of 153 children (94.1%). Of the 20 (13.0%) who required a top-up dose, 4 failed to sedate. The mean sedation onset was 29.4 minutes (SD: 24.3) and mean sedation duration was 56.5 minutes (SD: 24.0), with more than a third lasting more than 1 hour. The age of children, rather than initial dose of CH, was more relevant in determining success of sedation. Children who were >6 years old were 20.3 times more likely to fail sedation than those aged <2 years. During sedation, depression in the heart rate and a transient reduction of oxygen saturation was documented. All children recovered well post-sedation.

CONCLUSION

CH is a very useful sedative for paediatric ophthalmic procedures, especially in younger children. Children over 4 years old were more likely to fail sedation and require top-up doses. Alternative means of sedation may need to be considered in these cases.

Safety and efficacy of chloral hydrate for conscious sedation of infants in the pediatric cardiovascular intensive care unit

This study evaluates the safety and efficacy of chloral hydrate administration for the conscious sedation of infants in the pediatric cardiovascular intensive care unit (PCICU).We conducted a retrospective review of the charts of 165 infants with congenital heart disease who received chloral hydrate in our PCICU between January 2014 and December 2014. Chloral hydrate was administered orally or rectally to infants using doses of 50 mg/kg. We collected and analyzed relevant clinical parameters.The overall length of time to achieve sedation was ranged from 5 to 35 min (10.8 ± 6.2 min); the overall mean duration of sedation was ranged from 15 to 60 min (33.5 ± 11.3 min); and the overall mean length of time to return to normal activity was 10 min to 6 h (34.3 ± 16.2 min). The length of the PCICU stay was ranged from 3 to 30 days (8.2 ± 7.1 days). Physiologically, there were no clinically significant changes in heart rate, mean arterial pressure, respiratory rate, or peripheral oxygen saturation before, during, or after use of the chloral hydrate. There were no significant differences regarding sedative effects in the subgroups (cyanotic vs acyanotic group, with pulmonary infection vs without pulmonary infection group, and with pulmonary hypertension vs without pulmonary hypertension group).Our experience suggests that chloral hydrate is a safe and efficacious agent for conscious sedation of infants in the PCICU.

Retrospective Comparison of Intranasal Dexmedetomidine and Oral Chloral Hydrate for Sedated Auditory Brainstem Response Exams

OBJECTIVE

Satisfactory conditions for auditory brainstem responses (ABR) screening tests for pediatric hearing loss are usually achieved with oral chloral hydrate (CH) sedation. When the US manufacture of this drug was discontinued for business reasons, we developed an alternative sedation regimen using intranasal dexmedetomidine (IN DEX) 4 μg/kg. This institutional review board-approved retrospective study compared the efficacy and adverse effect profiles of these 2 sedative regimens.

METHODS

Medical records of children receiving oral CH or IN DEX for ABR were surveyed for demographic data and times from sedative administration to start and completion of the ABR procedure and recovery times. We also noted if the examination was completed with or without interruptions, failed for inadequate sedation, and if predefined cardiorespiratory adverse events occurred.

RESULTS

In the IN DEX cohort, the examination could be completed more frequently with a single dose of medication (P = .002). Satisfactory sedation in these patients permitted an earlier start of both the ABR examination and recovery to the awake status (P < .001 and < .045, respectively). Hypoxia requiring oxygen therapy was more frequent in the CH group.

CONCLUSIONS

This retrospective study found that IN DEX provides effective sedation for ABR examinations, with the benefits of an ability to begin the test sooner and complete the examination with a single dose, in addition to a decreased incidence of hypoxemia. A randomized controlled trial should test the hypothesis that the IN DEX technique is superior to the well-established standard oral CH regimen.

[Effect of neonatal perioperative anesthetic exposure in cardiac surgery on neuro- developmental outcomes in preschool children]

OBJECTIVE

To evaluate the effect of neonatal perioperative anesthetic exposure in complex cardiac surgery on neurodevelopmental outcomes in preschool children.

METHODS

General clinical data and data concerning anesthetic exposure were collected from 89 infants undergoing complex cardiac surgery at Sichuan People' Hospital. The cohort was followed for neurodevelopment till preschool age (48-72 months) and assessed with Wechsler Preschool and Primary Scale of Intelligence-III, Beery-Buktenica Developmental Test of Visual Motor Integration (VMI-V), and General Adaptive Composite (GAC) of the Adaptive Behavior Assessment System-II.

RESULTS

Seventy-one children were enrolled into the final analysis. Multiple linear regression found days on benzodiazepines (beta;=-0.49, P=0.005) and cumulative dose of benzodiazepines (β=-0.10, P=0.023) were associated with the full-scale IQ in these preschool children. Days on benzodiazepines (beta;=-0.39, P=0.009) and on chloral hydrate (beta;=-1.19, P=0.020) were associated with lower performance intelligence quotient (PIQ) at the preschool age. Cumulative dose of benzodiazepine exposure (beta;=-0.008, P=0.012) was associated with lower VMI scores. No correlations of other sedation/analgesia variables were found with the full-scale IQ, PIQ, Verbal IQ, VMI, or GAC scores.

CONCLUSION

We found a significant association of days on benzodiazepines, cumulative dose of benzodiazepines, and days on chloral hydrate in neonatal cardiac surgery with neurodevelopmental outcomes at the preschool age, suggesting the need of minimizing anesthetic exposure during a neonatal cardiac surgery to improve the children's neurodevelopmental outcomes.

Oral Sedation Postdischarge Adverse Events in Pediatric Dental Patients

The study investigated patient discharge parameters and postdischarge adverse events after discharge among children who received oral conscious sedation for dental treatment. This prospective study involved 51 patients needing dental treatment under oral conscious sedation. Each patient received one of various regimens involving combinations of a narcotic (ie, morphine or meperidine), a sedative-hypnotic (ie, chloral hydrate), a benzodiazepine (ie, midazolam or diazepam), and/or an antihistamine (ie, hydroxyzine HCl). Nitrous oxide and local anesthesia were used in conjunction with all regimens. After written informed consent was obtained, each guardian was contacted by phone with specific questions in regard to adverse events following the dental appointment. Out of 51 sedation visits, 46 were utilized for analysis including 23 boys and 23 girls ranging from 2 years 2 months to 10 years old (mean 5.8 years). 60.1% of patients slept in the car on the way home, while 21.4% of that group was difficult to awaken upon reaching home. At home, 76.1% of patients slept; furthermore, 85.7% of patients who napped following the dental visit slept longer than usual. After the appointment, 19.6% exhibited nausea, 10.1% vomited, and 7.0% experienced a fever. A return to normal behavior was reported as follows: 17.4% in <2 hours, 39.1% in 2-6 hours, 28.3% in 6-10 hours, and 15.2% in >10 hours. Postdischarge excessive somnolence, nausea, and emesis were frequent complications. The time to normality ranged until the following morning demonstrating the importance of careful postdischarge adult supervision.

A comparison of sedation-related events for two multiagent oral sedation regimens in pediatric dental patients

PURPOSE

This study compared the incidence of adverse sedation-related events occurring with two different multiagent oral sedation regimens in pediatric dental patients.

METHODS

Forty healthy patients (three to six years old), received either a sedation regimen of chloral hydrate, meperidine, and hydroxyzine with nitrous oxide (CH/M/H/N2O; N=19) or a regimen of midazolam, meperidine, and hydroxyzine with nitrous oxide (MZ/M/H/N2O; N=21). The two treating dentists answered a questionnaire regarding the perioperative period. Parents received two phone interviews at eight and 24 hours after sedation. Statistical analysis included chi-square, Pearson correlation coefficient, and t-test (P<.05).

RESULTS

Children sedated with MZ/M/H/N2O showed a significant increase in hyperactivity during dental treatment, slurring/difficulty speaking, and difficulty walking postoperatively within eight hours after discharge. Children sedated with CH/M/H/N2O showed a significant increase in frequency of sleeping, talking less than normal after arriving home, and an increased need for postoperative pain medication.

CONCLUSIONS

Different oral sedation regimens produce different adverse sedation-related events. The provider of pediatric oral sedation should select a sedative regimen with an adverse sedation-related profile that he/she believes is optimal for the patient being treated. Parents should be counseled as to possible postsedation effects anticipated based on the sedative regimen administered.

The safety and efficacy of chloral hydrate sedation for pediatric ophthalmic procedures: a retrospective review

PURPOSE

To determine the safety and efficacy of high-dose oral chloral hydrate for pediatric ophthalmic procedures.

METHODS

This study is a retrospective review of a quality audit of pediatric sedation for ophthalmic evaluation and imaging performed at King Khaled Eye Specialist Hospital between January 1 and December 31, 2011, in children aged 1 month to 6 years.

RESULTS

Three hundred fifty-eight of 380 (94.2%) sedation procedures were successful after a single dose of chloral hydrate, with 356 of 380 (93.7%) children sedated within 45 minutes of the first dose. The total success rate of the sedation procedure increased to 97.9% (372 of 380) when a second dose was administered. Children adequately sedated after a single dose of chloral hydrate were on average younger and weighed less than children who required additional doses. No major adverse events were documented.

CONCLUSIONS

The use of chloral hydrate sedation for ophthalmic evaluation and imaging was safe and effective in this patient population with a high rate of procedure completion.

Evidence for the use of isoflurane as a replacement for chloral hydrate anesthesia in experimental stroke: an ethical issue

Since an ethical issue has been raised regarding the use of the well-known anesthetic agent chloral hydrate, owing to its mutagenic and carcinogenic effects in animals, attention of neuroscientists has turned to finding out an alternative agent able to meet not only potency, safety, and analgesic efficacy, but also reduced neuroprotective effect for stroke research. The aim of this study was to compare the potential of chloral hydrate and isoflurane for both modulating the action of the experimental neuroprotectant MK801 and exerting analgesia. After middle cerebral artery occlusion in rats, no difference was observed in 24 h survival rate, success of ischemia, or infarct volume reduction between both anesthetics. However, isoflurane exerted a more pronounced analgesic effect than chloral hydrate as evidenced by formalin test 3 hours after anesthesia onset, thus encouraging the use of isoflurane in experimental stroke models.

Chloral hydrate sedation for magnetic resonance imaging in newborn infants

BACKGROUND

The aim of this study was to look for clinically significant adverse effects of chloral hydrate used in a large cohort of infants sedated for magnetic resonance imaging.

METHOD

Case notes of infants who underwent magnetic resonance imaging (MRI) scanning from 2008 to 2010 were reviewed, with patient demographics, sedation dose, comorbidities, time to discharge, and side effects of sedation noted.

RESULTS

Four hundred and eleven infants (median [range] postmenstrual age per weight at scan 42 [31(+4) -60] weeks per 3500 g [1060-9900 g]) were sedated with chloral hydrate (median [range] dose 50 [20-80] mg·kg(-1)). In three cases (0.7%), desaturations occurred which prompted termination of the scan. One infant (0.2%) was admitted for additional observation following sedation but had no prolonged effects. In 17 (3.1%) cases, infants had desaturations which were self-limiting or responded to additional inspired oxygen such that scanning was allowed to continue.

CONCLUSION

When adhering to strict protocols, MRI scanning in newborn infants in this cohort was performed using chloral hydrate sedation with a relatively low risk of significant adverse effects.

A comparative study on the sedative effect of oral midazolam and oral chloral hydrate medication in lumbar puncture

OBJECTIVE

Lumbar puncture (LP) is usually associated with anxiety and apprehension in children and their parents. This study was performed for controlling children's anxiety before and during LP and increasing the success of LP due to relaxation of the child following the use of sedative drugs and to compare the efficacy and side effects of oral midazolam and oral chloral hydrate.

METHOD

This prospective randomized controlled clinical trial included 160 children aged 2-7 years, candidates for LP. They were divided into two randomized groups of 80 children each: group I received 80 mg/kg oral chloral hydrate and group II received 0.5 mg/kg oral midazolam before LP.

RESULTS

The results indicated that the mean sedation grade was 3.8 +/- 1.0 in chloral hydrate group and 2.3 +/- 0.9 in midazolam group (P < 0.001). The mean onset of sedative effect was 30.9 +/- 8.8 min in midazolam group and 16.5 +/- 5.8 min in chloral hydrate group (P < 0.001). Prolonged sedation was the most common side effect in oral midazolam group (94.4%) versus 22.2% in chloral hydrate group.

CONCLUSION

Based on the level of sedation, side effects, time to onset of sedation and recovery time from sedation, oral chloral hydrate is a better sedative medication than oral midazolam.

The safety of sedation for overweight/obese children in the dental setting

PURPOSE

The goal of this study was to examine childhood overweight/obesity as a risk factor for adverse events during sedation for dental procedures.

METHODS

This was a cross-sectional, retrospective, IRB-approved study that included 17 years of data (1992-2009). The outcome variables were desaturation, nausea/vomiting, prolonged sedation, and true apnea. The major explanatory variables were weight percentiles and BMI percentiles.

RESULTS

A total of 510 patients met the inclusion criteria. Of these, 431 (86%) experienced no adverse events, 73 (14%) experienced one or more adverse events, and 6 had missing data. BMI data were available for a nested cohort of 103 children. Patients who experienced one or more adverse events had higher mean weights and BMI percentiles, though differences were not statistically significant. Another way to conceptualize the BMI data is to consider that 12% of the normal weight children experienced one or more adverse events versus 18% of the overweight/obese.

CONCLUSIONS

Overall, weight percentiles were higher in children who had one or more adverse events. Similarly, patients with higher BMI percentiles were more likely to experience adverse events. Although preliminary in nature, these findings suggest that childhood overweight/obesity may be associated with adverse events during sedation for dental procedures.

Life threatening intracerebral hemorrhage with isometheptene mucate, dichlorophenazine and acetaminophen combination therapy

A 45 year old female with no stroke risk factors suffered a massive intracerebral hemorrhage (ICH) after ingesting Midrin--a combination of isometheptene mucate, dichlorophenazine and acetaminophen. Neuroimaging revealed no evidence of structural disease or underlying vasculopathy. This is the first reported case of isometheptene induced ICH in the absence of underlying cerebrovascular disease. Physicians must be aware of the potential for this complication, and inquire about the use of isometheptene in unexplained cerebral hemorrhages. Neurological communities in countries with nonprescription isometheptene should discourage unsupervised or excessive use of the drug.

Severe central nervous and respiratory system depression after sedation with chloral hydrate: a case report

Chloral hydrate is generally considered a safe sedative-hypnotic drug, and is commonly used for sedation of infants and young children before diagnostic procedures. Even chloral hydrate administered within the recommended maximal dose limits can cause serious morbidity and mortality. Here the authors describe a four-month-old girl with a life-threatening central nervous system and respiratory depression after administration of a therapeutic dose of chloral hydrate. The patient gradually recovered with supportive treatment including ventilation therapy.

Sedation of neurologically impaired children undergoing MRI: a sequential approach

BACKGROUND

The purpose of this retrospective study was to determine the efficacy of a sequential approach meant to rescue failed chloral hydrate sedation and to obtain a low rate of adverse events along with predictable timings in neurologically impaired children undergoing magnetic resonance imaging.

METHODS

We retrospectively evaluated 1104 chloral hydrate sedations performed between 2002 and 2004 on 862 children weighing <26 kg. If the desired sedation score (3 on the Skeie Scale) was not reached within 30 min after oral administration of chloral hydrate, sedation was considered as potentially failed, and supplementation with sevoflurane, i.m. or i.v. ketamine, and i.v. pentobarbital and midazolam was started.

RESULTS

Twenty-seven sessions failed because of excessive movement. Mean induction time was significantly higher for patients who received supplementation (52.2 min vs 39.1 min), while no differences in recovery and total sedation times were found. Supplementation significantly increased the incidence of respiratory obstruction (4.6% vs 2.4%), although the incidence of other adverse events was unaffected.

CONCLUSIONS

Administering up to 1.5 g of chloral hydrate without supplementation was associated with a failure rate of approximately 20%, but the proposed sequential approach enabled us to rescue the majority of failed sedations while maintaining an acceptably low incidence of adverse events.

Sleep/sedation in children undergoing EEG testing: a comparison of chloral hydrate and music therapy

This study included a total of 60 pediatric patients ranging from 1 month through 5 years of age. The effects of chloral hydrate and music therapy were evaluated and compared as means of safe and effective ways to achieve sleep/sedation in infants and toddlers undergoing EEG testing. The results of the study indicate that music therapy may be a cost-effective, risk-free alternative to pharmacological sedation.

Sedation and Anesthesia Protocols Used for Magnetic Resonance Imaging Studies in Infants: Provider and Pharmacologic Considerations

Most studies report the efficacy of only a single drug to achieve sedation in a broad age range of children. In clinical practice, a variety of sedative and anesthetic regimes are monitored by nurses and physicians. In this study we report the efficacy of a tiered approach to monitoring and sedation in infants. Two-hundred-fifty-eight infants who required magnetic resonance imaging (MRI) studies received either oral chloral hydrate (n = 102) or bolus doses of IV pentobarbital (n = 67) monitored by nurses or IV propofol infusion (n = 68) titrated by physicians. Fewer cardiorespiratory events were observed in the chloral hydrate group (2.9%) compared to pentobarbital (13.4%) and propofol groups (13.6%); P < 0.05, propofol versus chloral hydrate. Infants who received propofol were ready to begin MRI scanning earlier (mean 9.1 +/- 6.7 min) than infants who received oral chloral hydrate (mean 23.5 +/- 13.4 min; P < 0.05). The time to discharge was longest in the pentobarbital (mean 80.3 +/- 39.2 min) and shortest in the propofol group (mean 53.9 +/- 30.1 min; P < 0.05). Infants in the chloral hydrate group moved more frequently (22.5%) during MRI scanning (with four sedation failures of 102) compared to 12.2% in the pentobarbital group and 1.4% in the propofol group (P < 0.001).

Chloral hydrate sedation for pediatric echocardiography: physiologic responses, adverse events, and risk factors

OBJECTIVE

The physiologic responses to chloral hydrate sedation in the setting of a pediatric echocardiography laboratory have not been well documented; neither has the population at risk been identified adequately. The purpose of this study was to describe the physiologic responses to chloral hydrate sedation, to report the occurrence of adverse events, and to identify any risk factors that predicted these adverse events in children who underwent sedation for echocardiography at our institution.

METHODS

We analyzed retrospectively 1095 patients who were sedated for echocardiography. Vital signs and oxygen saturations were recorded every 5 minutes, and adverse events were noted. Potential risk factors for sedation-related adverse events were analyzed.

RESULTS

Thirty-eight percent of patients were classified as American Society of Anesthesiologists class 3 or 4, reflecting the significant comorbidity in the study population. Hemodynamic responses to chloral hydrate sedation included > or = 20% decreases in heart rate (24% of the patients) and blood pressure (59% of the patients). There were no deaths or permanent morbidity. Adverse events occurred in 10.8% of patients and included apnea (n = 3 [0.3%]), airway obstruction (n = 15 [1.4%]), hypoxia (n = 65 [5.9%]), hypercarbia (n = 40 of 603 [6.6%]), hypotension with poor perfusion (n = 4 [0.4%]), vomiting (n = 4 [0.4%]), and prolonged sedation (n = 36 [3.3%]). No intervention was required in 92.5%, minor interventions were necessary in 7%, and major interventions were required in 0.5% of all patients. Multivariate analysis identified only age younger than 6 months as a predictor for adverse events, whereas cyanosis, hospitalization, American Society of Anesthesiologists class, fasting time, oxygen requirement, and use of additional sedation were not predictors.

CONCLUSIONS

Moderate decreases in heart rate and blood pressure, in the absence of clinical deterioration, are expected responses to chloral hydrate sedation in this pediatric population. The majority of adverse events were minor, and major events were uncommon. Infants who were younger than 6 months were found to be at higher risk for serious adverse events.

Electrocardiographic changes with segmental akinesia after chloral hydrate overdose

We report a case of deliberate ingestion of 12.5 g chloral hydrate in a 25-year-old psychiatric patient. Coma and life-threatening ventricular dysrhythmias were observed soon after ingestion. Repeated electrocardiographic examination was consistent with ischemic changes appearing on day 3. They were associated with segmental abnormal left ventricular wall motion by echocardiography. A coronary angiogram was performed and was normal. Toxic metabolites of chloral hydrate, trichloroethanol and trichloroacetic acid were found in the urine until day 7. This case illustrates that with halogenated aliphatic hydrocarbons, sustained changes in cardiac contractility may occur in addition to early life-threatening ventricular dysrhythmias.

Severe Esophageal Burn Following Chloral Hydrate Overdose in an Infant

Chloral hydrate is generally considered to be a safe hypnotic drug, and is commonly used for short-term sedation before diagnostic procedures. Its irritant actions to the mucous membranes are usually limited. We report a rare complication of chloral hydrate overdose in an infant. An 8-month-old male infant became unconscious and required ventilation support after an overdose of chloral hydrate was administered to provide sedation for an ophthalmologic examination. White plaques and sloughing of the oropharyngeal mucosa were observed on the next day. Esophagogastroscopy revealed severe corrosive lesions on the whole esophagus. The child recovered after supportive treatment and his oral intake remained well without dysphagia after 1 year. This report illustrates the potential corrosive effect of chloral hydrate. Strict attention should be paid to the dosing and administration protocol of chloral hydrate in infants. The condition of the oropharyngeal mucosa should be carefully monitored after chloral hydrate administration.

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.

Adverse cardiovascular and respiratory events during sedation of pediatric patients for imaging examinations

PURPOSE

To retrospectively identify factors associated with an increased risk of adverse cardiovascular or respiratory events during sedation of pediatric patients for imaging examinations.

MATERIALS AND METHODS

This HIPAA-compliant study was institutional review board approved; the requirement for informed consent was waived. All sedation information--including patient demographics, medications (doses and routes of administration), time required to sedate and before discharge, American Society of Anesthesiologists physical status classification, adverse events, and failed sedations--was maintained in a computerized database. A review of the data on all patients sedated between 1997 and 2003 for magnetic resonance imaging, computed tomography, and interventional radiology revealed associated adverse respiratory events in 70 patients. Adverse respiratory event was defined as oxygen desaturation of at least 5%, pulmonary aspiration, and need for airway resuscitation. Adverse cardiovascular events were defined as cardiac arrest and hemodynamic changes requiring medical therapy. Adverse events were compared between sedation regimens--which included fentanyl, chloral hydrate, pentobarbital, and midazolam hydrochloride--by using the Fisher exact test. Multiple logistic regression analysis was applied to identify potential predictors of adverse events.

RESULTS

Among 16,467 sedations performed, 70 (0.4%) were associated with adverse respiratory events: 58 cases of oxygen desaturation, two pulmonary aspirations, 10 cases of airway resuscitation, and no cardiovascular events. Nearly 30% (n = 20) of the 70 patients who had an adverse event had a history of serious respiratory illness. Logistic regression analysis revealed that neither patient age, weight, or sex nor type of imaging procedure was associated with an increased risk of an adverse event. Use of a single sedation agent was associated with lower adverse event risk than was use of multiple agents (P < .001).

CONCLUSION

Consideration should be given to using single agents, avoiding the use of multidrug sedation regimens, and recognizing that a history of pulmonary disease could be associated with an increased risk of adverse respiratory events despite a currently stable respiratory state.

Pharmacodynamics of chloral hydrate in former preterm infants

The aim of this study was to document the pharmacodynamics of chloral hydrate in former preterm infants at term post-conception age. The degree of sedation (COMFORT), feeding behaviour and cardiorespiratory events (bradycardic events, apnoeas) before and after administration of chloral hydrate (oral, 30 mg/kg) were prospectively evaluated in former preterm infants during procedural sedation. Characteristics at birth, during neonatal stay and at inclusion were collected. Paired Wilcoxon and McNemar tests were used to study the impact of chloral hydrate. Characteristics of infants who displayed severe bradycardic events were compared to infants in whom no bradycardic events were recorded (Mann Whitney U, Fischer's exact). A significant increase in sedation (decrease COMFORT scale) was observed up to 12 h after administration. There was a minor but significant decrease in oral intake (161 to 156 ml/kg/day, P < 0.01). A significant increase in the number of bradycardic events (<80/min: 38 to 82 events, of which < 70/min: 30 to 79 of which < 60/min: 15 to 45; at least P < 0.01) and in the duration of the most severe bradycardic event (8-12.5 s) was observed. Therefore, further inclusion was stopped when 26 neonates were included. Infants who displayed severe bradycardic (< 60/min) events ( n = 13) after administration of chloral hydrate had a lower gestational age at birth without difference in post-conception age at inclusion.

CONCLUSION

Chloral hydrate was associated with an increase in unintended side-effects in former preterm infants, likely reflecting population specific pharmacodynamics and kinetics of chloral hydrate.

Chloral hydrate. An effective agent for sedation in children with age and weight dependent response

OBJECTIVE

Diagnostic and therapeutic procedures in children are made easier using sedation. However, there is no consensus about which drug should be used to achieve this. Furthermore, none of the drugs used for sedation are risk free. The aim of this work is to study sedation indications, effectiveness, and safety at our center.

METHODS

A prospective observational study conducted at the Pediatric Day Care Unit, King Fahad National Guard Hospital, Riyadh, Saudi Arabia. The study covered 17.5 weeks in 2 periods: May 9th 1999 to June 13th 1999 and October 31st 2001 to February 11th 2002. Children <12 years were included. Collected data included demographics, indication, drug dosing and outcome. Data were reported as mean +/- SD.

RESULTS

We included 148 patients, age 38 +/- 30 months. Adequate sedation was achieved in 79% after initial chloral hydrate (CH) dose of 56.9 +/- 9.3 mg/kg, in 95% after adding 18.5 +/- 6.4 mg/kg CH and in 96% after adding second drug. Compared to nonrespondents, first CH dose respondents were younger and lower in weight. The CH side effects were few and mild.

CONCLUSION

Chloral hydrate is a safe and effective agent for sedation in children with an age and weight dependent response.

The assessment of genotoxic effects in lymphocyte cultures of infants treated with chloral hydrate

Chloral hydrate is a sedative commonly used in pediatric medicine. It was evaluated for genotoxicity in cultured peripheral blood lymphocytes of infants who were given chloral hydrate for sedation. Sister chromatid exchange and micronucleus frequencies were determined before and after chloral hydrate administration. After treatment, the frequencies of sister chromatid exchange and micronuclei were significantly increased, suggesting that chloral hydrate has moderate genotoxic potential in infants.

[Chloral hydrate and diarrhea. A 76-year-old retired administration employee]

Ein 76-jähriger Patient klagte über eine seit zwei Monaten andauernde Diarrhoe mit schmerzlosem wässrigen Stuhlgang. In der Koloskopie fanden sich polypoide ödematöse Aufwerfungen und in der Abdomenleeraufnahme gasgefüllte Zysten. Die in diesem Fall diagnostizierte Pneumatosis intestinalis (PI) wurde auf die Einnahme von Chloralhydrat zurückgeführt. Das Absetzen führte zur vollständigen Rückbildung der Symptomatik und der beschriebenen pathologischen Befunde.

Pentobarbital vs chloral hydrate for sedation of children undergoing MRI: efficacy and recovery characteristics

BACKGROUND

Chloral hydrate (CH) sedation for magnetic resonance imaging (MRI) is associated with significant failure rates, adverse events and delayed recovery. Pentobarbital (PB), reportedly produces successful sedation in 98% of children undergoing diagnostic imaging. This study compared the efficacy, adverse events and recovery characteristics of CH vs PB in children undergoing MRI.

METHODS

With Institutional Review Board approval and written consent, children were randomly assigned to receive intravenous (i.v.) PB (maximum 5 mg x kg(-1) in incremental doses) or oral CH (75 mg x kg(-1)) prior to MRI. Sedation was augmented with 0.05 mg x kg(-1) doses of i.v. midazolam (maximum 0.1 mg x kg(-1)) as necessary. Adverse effects, including hypoxaemia, failed sedation, paradoxical reactions and behavioural changes, the return of baseline activity, and parental satisfaction were documented. The quality of MRI scans was evaluated by a radiologist blinded to the sedation technique.

RESULTS

PB facilitated an earlier onset of sedation (P = 0.001), higher sedation scores (P = 0.01), and less need for supplemental midazolam compared with CH. Severe hypoxaemia occurred in two children (6%) in the PB group. Fourteen per cent of the PB group experienced a paradoxical reaction, 9% sedation failure and 11% major motion artefact, compared with 0% (P = 0.05), 3 and 2% (P = NS), respectively, in the CH group. CH and PB were both associated with a high incidence of motor imbalance, and agitation. However, children who received PB had a slower return to baseline activity (P = 0.04).

CONCLUSIONS

Although PB facilitated a quicker sedation onset and reduced the requirement for supplemental sedation, it produced a higher incidence of paradoxical reaction and prolonged recovery with a similar failure rate compared with CH.

Pediatric medical errors part 2: case commentary. A source of tremendous loss

The Dowdell (2004) case report chills the reader. We must learn through its publication methods of prevention of medication error. The attached guidelines provided by the ISMP can lead us in a more cautious direction. Knowledge of the float regulations would have required that the involved hospital had ensured that a float nurse to pediatrics understood that medication dosages were weight dependent and that calculations were required prior to drug administration. Adequate staffing might have prevented the need for a float nurse and allowed for more attention to double checking calculations and drug administration. Dissemination of the guidelines from the AAP or those recommended by the SPN might have prevented this error. The age-old story of impoverished physician-nurse interaction has outlived its place in history. Nurse-physician collegiality and investment in the team approach will save children's lives.

Sedation in children undergoing CT scan or MRI: effect of time-course and tolerance of rectal chloral hydrate

The aim of this paper was to describe the time-course of the sedative effect of rectal chloral hydrate (75 mg/kg) in children undergoing CT scan or MRI. Twenty children (2.13 +/- 1.43 years old) were administered 75 mg/kg chloral hydrate rectally (chloralhydrat-rectiole rectal formulation, Dr Mann-Pharma Lab, Berlin, Germany), before a CT scan or an NMR imaging. Sedation was measured at specific times using a sedation score of 1-6. Patients were continuously monitored for respiratory and heart rate, systolic and diastolic blood pressures, and oxygen saturation. About 82.35 and 94.11% of the patients had a score of sedation > or = 3 within 15 and 30 min, respectively. The mean time to effective sedation (score > or = 3) was of 0.30 +/- 0.14 h (median time, 0.25 h). The mean duration of effective sedation (score > or = 3) was 1.29 +/- 1.05 h (median duration, 0.75 h). A total of 93.1% of the X-ray sections were obtained without artifact and sedation was considered by radiologists to be efficient for 83.3% of the procedures. This sedation procedure appeared efficient and safe during ambulatory CT scan and NMR imaging. The long-term effect of chloral hydrate, however, remains to be evaluated.