Chloral Hydrate Sedation Research Articles

Utilisation of an outpatient sedation unit in paediatric ophthalmology: safety and effectiveness of chloral hydrate in 1509 sedation episodes

ObjectiveTo report the largest study on the safety and effectiveness of sedation in paediatric ophthalmology in a nurse-led outpatient sedation unit.DesignRetrospective cohort study reviewing all children who underwent sedation from...

Cardio‐respiratory response to moderate chloral hydrate sedation in young lambs

Chloral hydrate (CH) is the most commonly used sedative for medical procedures and lung function tests in infancy. The aim was to determine whether moderate CH sedation affects airway function, lung volume and ventilation. Thirteen chronically instrumented 7- to 8-week-old lambs were studied both before and after CH sedation (50mg/kg as intravenous bolus followed by 25mg/kg/hour as continuous infusion). Nitrogen washout technique and lung mechanics analysis were used to assess functional residual capacity (FRC) and airway function. Moment analysis and lung clearance index were calculated as measures of gas mixing efficiency in distal airways. Respiratory rate, tidal volume, minute ventilation and indices of inspiratory drive were determined together with heart rate, blood pressure and oxygenation. No significant CH-induced changes were found for gas mixing efficiency, FRC or lung mechanics. Minute ventilation decreased slightly, but significantly, while indices of inspiratory drive remained unchanged. Heart rate increased significantly, but mean arterial blood pressure was unaffected. Moderate CH sedation did not significantly affect airway function or FRC. Although indices of inspiratory drive were not affected, minute ventilation decreased slightly. These findings indicate that reliable results can be obtained from lung function testing when CH is used for sedation.

Auditory brainstem responses to broad-band chirps: Amplitude growth functions in sedated and anaesthetised infants

ObjectiveRecently an optimized broad-band chirp stimulus has been proposed for the objective estimation of hearing thresholds with auditory brainstem responses (ABRs). Several studies have demonstrated that this stimulus, compensating for the travelling wave delay of the frequency components of a click stimulus at the basilar membrane, evokes larger ABR amplitudes in adults. This study analyses the amplitude of chirp-evoked ABRs recorded in infants below 48 month of age under clinical conditions and compares these results with literature data. MethodsChirp-evoked ABR recordings in 46 infants under chloral hydrate sedation or general anaesthesia were analysed retrospectively. The amplitude of the wave V was measured as a function of the stimulus intensity. To compare ABR amplitudes across infants with different hearing losses, the stimulus intensity was readjusted to the subjects’ individual physiological threshold in dB SL (sensation level). Individual wave V amplitudes were plotted against stimulus intensity and individual amplitude growth functions were calculated. To investigate the maturation of chirp-evoked ABR, data from infants below and above 18 months of age were analysed separately. ResultsChirp-evoked ABR amplitudes in both age groups were larger than the click-evoked ABR amplitudes in young infants from the literature. Amplitudes of chirp-evoked ABR in infants above 18 months of age were not substantially smaller than those reported for normal hearing adults. Amplitudes recorded in infants below 18 months were significantly smaller than those in infants above 18 months. A significant difference between chirp-evoked ABR amplitudes recorded in sedation or under general anaesthesia was not found. ConclusionsThe higher amplitudes of ABR elicited by a broadband chirp stimulus allow for a reduction of the recording time in young infants.

Analysis of the appropriate age and weight for pediatric patient sedation for magnetic resonance imaging

Sedatives with a long duration are required for pediatric magnetic resonance imaging (MRI) in the emergency department. The success rate of chloral hydrate for pediatric sedation is 80% to 100% according to some studies. However, the success rate varies by age, weight, and underlying disease. To identify factors affecting the success rate, we compared the chloral hydrate sedation success rate and adverse event rate by age, weight, and underlying disease. Compared with patients in the failure group, patients in the successful group were younger (23.8 vs 36.9 months, P < .01) and weighed less (11.4 vs 14.4 kg, P < .01). No differences in neurological problems, reasons for MRI, or adverse events were observed between the 2 groups. Patients 18 months old had a success rate greater than 95%, but the success rate decreased in children older than 18 months. The adverse event rate was about 10% in patients 18 months old and increased to 20% in patients older than 36 months. Patients 24 months of age who had a neurological problem (seizure disorder or developmental delay) had a success rate greater than 95%, but the adverse event rate increased after 24 months of age. Chloral hydrate sedation was appropriate for pediatric MRI in patients younger than 18 months. Although we observed no fatal adverse events, it is necessary to monitor patients until full recovery from sedation.

Chloral hydrate sedation in radiology: retrospective audit of reduced dose

Chloral hydrate (CH) is safe and effective for sedation of suitable children. The purpose of this study was to assess whether adequate sedation is achieved with reduced CH doses. We retrospectively recorded outpatient CH sedations over 1year. We defined standard doses of CH as 50mg/kg (infants) and 75mg/kg (children >1year). A reduced dose was defined as at least 20% lower than the standard dose. In total, 653 children received CH sedation (age, 1month-3years 10months), 42% were given a reduced initial dose. Augmentation dose was required in 10.9% of all children, and in a higher proportion of children >1year (15.7%) compared to infants (5.7%; P < 0.001). Sedation was successful in 96.7%, and more frequently successful in infants (98.3%) than children >1year (95.3%; P = 0.03). A reduced initial dose had no negative effect on outcome (P = 0.19) or time to sedation. No significant complications were seen. We advocate sedation with reduced CH doses (40mg/kg for infants; 60mg/kg for children >1year of age) for outpatient imaging procedures when the child is judged to be quiet or sleepy on arrival.

Safety Profile of Chloral Sedation for MRI in Term and Preterm Neonates

Background: Chloral hydrate is a widely used sedative for MRI scanning in the newborn. However some studies suggest that infants may have a relatively high risk of complications1. The aim of this study was to assess the adverse effects of sedation in a large cohort of neonates. Method: Infants >32 weeks gestation undergoing brain MRI at our institution are sedated and monitored according to strict protocols. Casenotes of infants who underwent MRI scanning from 2008-2010 were retrospectively reviewed. Infant demographics were recorded, along with sedation dose, comorbidities, time to discharge and side effects of sedation including oxygen requirement and significant desaturation/apnoea. Results: 411 infants (median gestation/weight at scan 42weeks/3500grams) were sedated with chloral hydrate(median dose 50mg/kg). 408(99.3%) infants completed the scan. The overall complication rate was 5.1%(95% confidence limits 2.9-7.3%). Desaturation or additional O2 requirement occurred during MRI scan in 20 babies(4.9%), but episodes were all short-lived and did not delay discharge home. 1 patient required overnight observation following an apnoeic episode post-MRI, but was discharged without complication the following day. There were no significant differences in gestational age(p=0.16), corrected gestation at scan(p=0.62), weight at scan(p=0.19) or sedation dose(p=0.29) between the affected and non-affected groups. Lower birthweight was associated with fewer adverse events(p=0.03), presumably because higher birthweight babies were scanned following neurological insult. Conclusion: When adhering to strict protocols and with adequate monitoring, chloral hydrate sedation for MRI scanning can be safely performed for both preterm and term infants.

Chloral Hydrate Sedation in Term and Preterm Infants

Chloral Hydrate Sedation in Term and Preterm Infants

Chloral Hydrate Sedation in Infants: Safety and Efficacy

Chloral Hydrate Sedation in Infants: Safety and Efficacy

Safety After Chloral Hydrate Sedation of Former Preterm and Term Infants for Magnetic Resonance Imaging: Are the Data Clear?

Safety After Chloral Hydrate Sedation of Former Preterm and Term Infants for Magnetic Resonance Imaging: Are the Data Clear?

Chloral Hydrate Sedation in Term and Preterm Infants: An Analysis of Efficacy and Complications

Chloral Hydrate Sedation in Term and Preterm Infants: An Analysis of Efficacy and Complications

Chloral Hydrate Sedation in Term and Preterm Infants: An Analysis of Efficacy and Complications

Term and preterm infants are at risk of developing apnea after receiving general anesthesia. The risk of apnea after sedation with chloral hydrate (CH) in this population is unknown. In this study, we aimed to describe the clinical course of infants younger than 1 year who received CH for magnetic resonance imaging (MRI), with regard to the efficacy of CH sedation, the need for additional sedative drugs, and the incidence of oxyhemoglobin desaturation or need for oxygen supplementation. We aimed to determine the relationship between these factors to chronological age in term infants and gestational and postconceptional age (PCA) in preterm infants (<37 weeks' gestation). This was a retrospective cohort study of 1394 infants undergoing MRI examination with CH sedation. Infants with an endotracheal tube, tracheostomy tube, or congenital heart disease were excluded. Patient charts were examined in detail to determine independent risk factors and dependent outcome variables up to 24 hours after MRI. Univariate and multivariate analyses were performed to determine risk factors for outcome variables. Postprocedure oxyhemoglobin desaturation was more likely in inpatients (P < 0.001) and was associated with a lower body weight (3.9 +/- 2.1 kg vs 6.6 +/- 3.0 kg; P < 0.001), history of apnea (33.3% vs 9.9%; P = 0.001), higher ASA physical status (P = 0.002), and younger chronological age (58.7 +/- 82.8 days vs 152 +/- 105.9 days; P < 0.0001). When the preterm group was analyzed separately, the risk of postprocedure oxyhemoglobin desaturation was directly correlated with younger chronological age (56.0 +/- 41.5 days vs 150.6 +/- 107.1 days; P = 0.012) and younger PCA (39.5 +/- 4.1 weeks vs 54.4 +/- 15.2 weeks; P = 0.005), but not gestational age. Preterm infants had more postprocedure bradycardia than term infants (P = 0.005). Postprocedural oxyhemoglobin desaturation was not seen in preterm infants older than 48 weeks' PCA. Because of the relatively small percentage of cases (8 of 262) of postprocedural oxyhemoglobin desaturation in preterm infants, we were not able to definitively determine the difference in incidence between preterm and term infants. Additional doses of CH or supplementation with midazolam did not increase the incidence of complications. The occurrence of postprocedural oxyhemoglobin desaturation was directly correlated with younger chronological age in term infants and younger PCA in preterm infants. Term infants who required extended oxygen supplementation were inpatients and had significant comorbidities.

Light-adapted electroretinograms in optic nerve hypoplasia

The purpose of the study is to characterise retinal function using light-adapted electroretinograms (ERGs) in a series of young children with ONH, congenital dysplasia of retinal ganglion cells. ERGs were recorded with chloral hydrate sedation in 27 children with ONH (18 with bilateral and 9 with unilateral ONH, age 4-35 months) and an adult reference population (n = 12). Stimuli included ISCEV standard flash, oscillatory potentials (OPs) and standard flicker as well as a light-adapted luminance-response series (photopic hill). The disc diameter to disc macula (DD:DM) ratio was measured from fundus photographs. The results are eyes with ONH, classified by DD:DM, were severe (<or=0.15, n = 22), moderate (0.16-0.30, n = 22), mild (0.31-0.35, n = 1), and fellow eyes (>0.35, n = 9), all had prolonged ERG implicit times and smaller i-waves than those of adults. Eyes with moderate or severe ONH also had smaller amplitudes for OPs and flicker ERGs and required stronger flashes to obtain the peak b-wave amplitude. Abnormalities of the photopic hill were a common but inconsistent feature of ONH and were not indicative of ONH severity. Abnormalities of the photopic hill of the ERG suggest that some cases of ONH may have retinal dysfunction with specific deficits in the ON or OFF pathways of the retina. ONH is a complex and heterogeneous condition that may involve dysfunction distal to the retinal ganglion cells.

Functional Magnetic Resonance Imaging of the Sensorimotor System in Preterm Infants

Preterm birth at <32 weeks' gestational age has a specific predilection for periventricular white matter injury. Early prediction of concomitant motor sequelae is a fundamental clinical issue. Recently, functional MRI was introduced as a noninvasive method for investigating the functional integrity of the neonatal brain. We aimed at implementing a unilateral passive forearm extension/flexion functional MRI paradigm in a routine clinical MRI setup to allow noninvasive mapping of the sensorimotor system in preterm infants and to relate the functional data to structural and behavioral data. Eight patients (median gestational age: 26.5 weeks; median birth weight: 885 g) were included. The functional MRI was performed at term-equivalent age (median: 39 weeks' postconceptional age) under chloral hydrate (50 mg/kg) sedation. In 5 of 8 patients, functional MRI data acquisition was successful. This resulted in 10 functional data sets (5 for passive stimulation of each forearm). Unilateral stimulation was associated with mainly bilateral activation of the primary sensorimotor cortex (n = 7 of 10 data sets), the prevailing hemodynamic response being a negative blood oxygenation level-dependent signal. Positive blood oxygenation level-dependent response or failure to activate the sensorimotor cortex (n = 3 of 10 data sets) were seen in those patients with aberrant structural/behavioral indices. Our data show the feasibility of passive unilateral sensorimotor stimulation during neonatal clinical MRI protocols. The bilateral activation pattern observed at this age is compatible with a bilaterally distributed sensorimotor system. Our data validate initial accounts for a raised incidence of negative blood oxygenation level-dependent responses in the primary sensorimotor cortex at this developmental stage. The negative blood oxygenation level-dependent response is likely to reflect a reduction of the oxy/deoxy-hemoglobin ratio during a maturational stage characterized by rapid formation of synapses, yet ineffective processing. Positive blood oxygenation level-dependent responses or failure to activate the sensorimotor cortex may be an early indicator of abnormal development and will have to be followed up carefully.

Sedation of neurologically impaired children undergoing MRI: a sequential approach

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. 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. 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. 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.

Retinal function in infants with optic nerve hypoplasia: electroretinograms to large patterns and photopic flash

Optic nerve hypoplasia (ONH), which is defined as a congenital deficiency of retinal ganglion cells, may also involve more distal layers of the retina. We investigated electrophysiological function of the retina in ONH using electroretinograms (ERGs). ERGs were recorded from 48 subjects (3.5-35 months) with unilateral or bilateral ONH. Pattern reversal (4 degrees checks) was presented under chloral hydrate sedation, using an optical system to correct a cycloplegic refraction. A photopic flash stimulus was also used. Fundus photographs were used to measure the disk diameter/disk macula ratio (DD/DM), and to document other clinical signs. Eyes were classified as moderate (0.15-0.3) or severe (<0.15) ONH, and those with DD/DM greater than 0.3 were used as reference eyes. Pattern ERG recording was completed in 89 eyes and was detectable in 80% of eyes with ONH (61/76 tested) and in all 13 reference eyes. Photopic flash ERGs were of good quality in all eyes. The severity of ONH correlates with the amplitude of the photopic flash b-waves and with the amplitude of the N95 component of the pattern ERG (P<0.01). However, the ERGs to large patterns were well preserved (>3.5 microV) in 10 of 35 eyes with severe ONH. Tortuous retinal vessels in eyes with either moderate or severe ONH were associated with smaller amplitude photopic b-waves and markedly diminished or undetectable pattern ERGs. This study supports the hypothesis that retinal dysfunction distal to the ganglion cells is common in ONH, but is not predictable on the basis of ONH severity alone. Additionally, tortuous retinal vessels in ONH may be a sign associated with retinal dysfunction.

Chloral Hydrate Sedation for Pediatric Echocardiography: Physiologic Responses, Adverse Events, and Risk Factors

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. 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. 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. 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.

Safety and Efficacy of Submucosal Midazolam When Combined with Oral Chloral Hydrate, Hydroxyzine and Nitrous Oxide Sedation by using Houpt's Scale

Safety and Efficacy of Submucosal Midazolam When Combined with Oral Chloral Hydrate, Hydroxyzine and Nitrous Oxide Sedation by using Houpt's Scale

Effect of Submucosal Midazolam on Percutaneous Saturation Percentage of Oxygen (SpO2), End-tidal Carbon Dioxide (EtCO2) and Physiologic Response When Combined with Chloral Hydrate, Hydroxyzine and Nitrous Oxide Sedation

Effect of Submucosal Midazolam on Percutaneous Saturation Percentage of Oxygen (SpO₂), End-tidal Carbon Dioxide (EtCO₂) and Physiologic Response When Combined with Chloral Hydrate, Hydroxyzine and Nitrous Oxide Sedation

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.

Chloralhydrate in children undergoing echocardiography.

Transthoracic echocardiography (TTE) is a painless, noninvasive and risk-free diagnostic method in children with known or suspected congenital heart disease. Sedation is frequently required for an optimal achievement of this procedure. The purpose of this study was to determine the safety and efficacy of chloral hydrate (CH) sedation in undergoing TTE. The study population included 360 patients with a median age of 19 months. (2 weeks to 8 years). The median dosage of CH given was 75 mg/kg (ranging 50 and 100 mg), with either oral or rectal administration. Oral administration could not be achieved successfully in 90 patients (20%) because of the bitter taste of the drug, in the other 108 patients (30%), vomiting occurred immediately after drug administration. Prior to CH administration and until discharge; respiratory rate; heart rate, blood pressure and oxygen saturation were recorded. Sedation was successfully achieved in 342 (95%) of the patients. No child had a clinically significant change in heart rate, blood pressure and respiratory rate during sedation. There were also no significant differences in heart rate, respiratory rate, blood pressure and oxygen saturation before and after sedation. Although CH has a bitter taste and is a gastric irritant for oral medication, because of the minimal side effects and efficacy for sedation, it remains as a safe and successful drug for use in children for TTE.