Fatal Cardiac Arrest in 2 Children: Possible Role of Ondansetron

Causes of Perioperative Cardiac Arrest: Mnemonic, Classification, Monitoring, and Actions

Perioperative cardiac arrest (POCA) is a catastrophic complication that requires immediate recognition and correction of the underlying cause to improve patient outcomes. While the hypoxia, hypovolemia, hydrogen ions (acidosis), hypo-/hyperkalemia, and hypothermia (Hs) and toxins, tamponade (cardiac), tension pneumothorax, thrombosis (pulmonary), and thrombosis (coronary) (Ts) mnemonic is a valuable tool for rapid differential diagnosis, it does not cover all possible causes leading to POCA. To address this limitation, we propose using the preload-contractility-afterload-rate and rhythm (PCARR) construct to categorize POCA, which is comprehensive, systemic, and physiologically logical. We provide evidence for each component in the PCARR construct and emphasize that it complements the Hs and Ts mnemonic rather than replacing it. Furthermore, we discuss the significance of utilizing monitored variables such as electrocardiography, pulse oxygen saturation, end-tidal carbon dioxide, and blood pressure to identify clues to the underlying cause of POCA. To aid in investigating POCA causes, we suggest the Anesthetic care, Surgery, Echocardiography, Relevant Check and History (A-SERCH) list of actions. We recommend combining the Hs and Ts mnemonic, the PCARR construct, monitoring, and the A-SERCH list of actions in a rational manner to investigate POCA causes. These proposals require real-world testing to assess their feasibility.

Benefit-Risk Assessment of Off-Label Drug Use in Children: The Bravo Framework

A drug is granted a license for use after a thorough assessment of risks and benefits based on high-quality scientific proof of its efficacy and safety. Many drugs that are relevant to children are not licensed for use in this population implying that a thorough assessment of risks and benefits in the pediatric population has not been made at all, implying a negative risk-benefit balance in children, or implying insufficient information to establish the risk-benefit balance. Use of drugs without positive assessment of risks and benefits exposes children to potential lack of efficacy, unknown toxicity, and harm. To aid guideline committees and individual prescribers, we here present a tutorial of the Benefit and Risk Assessment for Off-label use (BRAvO) decision framework. This pragmatic framework offers a structured assessment of benefits and risks of off-label drug use, including a clinical pharmacological based approach to age-appropriate dose selection. As proof of concept and to illustrate the practical use, we have applied the framework to assess benefits and risks of off-label use of ondansetron for gastroenteritis-induced nausea and vomiting. The framework could also guide decisions on off-label use in other special populations (e.g., pregnant women, elderly, obese, or critically ill patients) where off-label drug use is frequent, thereby contributing to effective and safe pharmacotherapy.

Effect of ondansetron on vomiting associated with acute gastroenteritis in a developing country: a meta-analysis

In high-income countries. ondansetron is an effective antiemetic in children with gastroenteritis, but data from low- and middle-income countries are sparse. This study aimed to evaluate evidences of the effectiveness of ondansetron in preventing vomiting and reducing the use of intravenous fluids in children with gastroenteritis in developing countries. A total of nine randomized controlled trials (RCTs) involving 2313 participants met the inclusion criteria. Compared with placebo, ondansetron reduced the use of intravenous rehydration (three RCTs, n = 1126, relative risk (RR) 0.60, 95% confidence interval (CI) 0.38-0.95, no significant heterogeneity, I² = 43%), the risk of failure of oral rehydration therapy among children with gastroenteritis-associated vomiting and dehydration (four RCTs, n = 1370, RR 0.58, 95% CI 0.43-0.79; no significant heterogeneity was found, I² = 39%) and risk of hospitalization (2 RCTs, n = 264, RR 0.25, 95% CI 0.09-0.73, no heterogeneity, I² = 0).Conclusions: Compared with placebo, ondansetron reduced the use of intravenous fluids in children with gastroenteritis and dehydration. It has no effect on children with gastroenteritis who do not present with dehydration in developing countries. While ondansetron is effective in controlling vomiting and reducing the rate of hospitalization, there is no evidence that it is effective in reducing the rate of readmission. What is Known: • In high-income countries, ondansetron can reduce the use of intravenous fluids in children with gastroenteritis and dehydration. • No systematic review and meta-analysis of randomized controlled trials were done in a developing country setting. What is New: • In developing countries, ondansetron reduces the use of intravenous fluids in children with gastroenteritis and dehydration. • It has no effect on children with gastroenteritis but without dehydration.

Antiemetic drugs: what to prescribe and when

Nausea and vomiting are common symptoms with many possible causes, including the adverse effects of drugs. If a drug is indicated, the cause guides the choice of antiemetic drug The main antiemetic classes include antagonists of the serotonin, dopamine, histamine, muscarinic and neurokinin systems, corticosteroids and benzodiazepines. Some antiemetics appear more effective for specific indications Serotonin and neurokinin antagonists, such as ondansetron and aprepitant, are highly effective in treating chemotherapy-induced nausea and vomiting. Metoclopramide and antihistamines are first-line options for nausea and vomiting in pregnancy Serotonin antagonists and some dopamine antagonists, such as metoclopramide, can prolong the QT interval on the ECG. Dopamine antagonists can cause extrapyramidal adverse effects, particularly in children

Trends in Outpatient Prescription Medicine Use in New Zealand Children 2010-2015: A National Population-Based Study

BACKGROUND

Research examining trends in the outpatient prescription medicine use of New Zealand children is limited.

OBJECTIVES

Our objective was to provide an overview of prescription medicine use in New Zealand children and assess changing patterns in use from 2010 to 2015.

METHODS

We conducted a retrospective cohort study including all New Zealand primary care-registered children aged < 18 years using data from the national pharmaceutical claims database. We calculated the prevalence of use within four age groups in each year by anatomical therapeutic class, therapeutic group and drug. Rate ratios were calculated to compare the prevalence of use in 2010 and 2015.

RESULTS

In total, 1,496,026 children with a mean of 2.7 years of potential drug exposure were included. The overall prevalence of drug use was 70% in 2010 and 73% in 2015. In 2015, medicine use was highest in children aged < 2 years (90%) and lowest in children aged 12-17 years (65%). Antibacterials, analgesics, topical corticosteroids, non-steroidal anti-inflammatory drugs (NSAIDs) and antihistamines were the most widely used medicines. The prevalence of use of systemic and topical antibiotics decreased by 2 and 10%, respectively, between 2010 and 2015, but there was increased use of analgesics (10%), NSAIDs (39%), antihistamines (15%) and antinausea and vertigo agents (306%).

CONCLUSIONS

Our findings indicate areas for further research focusing on inappropriate prescribing to children and safety issues in children's medicine use. Monitoring changing patterns of use over time is important for the evaluation of effective therapies in children and any potential harmful consequences of prescribing.

Ondansetron and teratogenicity in rats: Evidence for a mechanism mediated via embryonic hERG blockade

The potent hERG channel blocking drug ondansetron is used off-label for treatment of nausea and vomiting in early pregnancy. Some human epidemiological studies have associated ondansetron with fetal cardiovascular defects and orofacial clefts. This study investigated the effects of ondanestron on embryonic heart rhythm of gestational day (GD) 13 rat embryos in vitro and then integrated the results with published animal teratology, and animal and human pharmacokinetic studies to perform a risk evaluation. Ondansetron caused concentration dependent bradycardia and arrhythmia. Cardiovascular malformations in rats occurred at exposures slightly higher than those in early human pregnancy. Together the results suggest that ondansetron can have teratogenic potential in rats and humans mediated via hERG block and severe heart rhythm disturbances in the embryo. The risk may be increased in human pregnancy if additional risk factors are present such as hypokalemia.

Impact of Pharmacist Intervention on Electrocardiogram Monitoring of Pediatric Patients on Multiple QTc Interval-Prolonging Medications

OBJECTIVES

To determine whether dedicated pharmacy services improve the rate of electrocardiogram (ECG) monitoring in patients at risk for medication-induced QTc interval prolongation. In addition, determine how pediatric institutions currently monitor patients at risk for medication-induced QTc interval prolongation.

METHODS

A pharmacist-driven monitoring protocol to detect medication-induced QTc interval prolongation was developed using published literature. If patients were prescribed 3 or more medications known to prolong the QTc interval, they were recommended to have a baseline ECG to assess the QTc interval. If 3 or more QTc interval-prolonging medications were administered for 5 or more days, a follow-up ECG was recommended. Patients prescribed medications known to prolong the QTc interval were identified. Prior to pharmacist intervention, electronic medical records were reviewed to determine if baseline and follow-up ECGs were obtained in patients meeting criteria for monitoring. A dedicated pharmacist then prospectively reviewed charts and recommended monitoring. The rate of monitoring during the intervention and baseline period was compared. To determine current practice at pediatric institutions, a survey was distributed to pharmacists.

RESULTS

Pharmacist intervention improved the rate of ECG monitoring in patients at risk for medication-induced QTc interval prolongation from 47.8% to 100% (p = 0.0009). Of the 55 survey participants, 6 stated their institution had QTc interval monitoring procedures in place, 35 did not have any, and 3 had procedures in process.

CONCLUSIONS

Targeted pharmacist intervention improved the rate of ECG monitoring in patients at risk for medication-induced prolonged QTc interval. Our research and survey data reveal that institutions could benefit from targeted pharmacist intervention to monitor patients for medication-induced QTc interval prolongation.

Effect of intravenous ondansetron on QTc interval in children with gastroenteritis

BACKGROUND

The potential for ondansetron to cause QT prolongation and fatal dysrhythmia is well-reported, including a 2011 FDA report on the topic. Few clinical trials evaluating this phenomenon in the ED setting exist, and only one is pediatric.

OBJECTIVE

We have sought to determine the effect of a standardized dose of intravenous ondansetron on the QTc duration of children under 14years of age treated for gastroenteritis-associated vomiting in a pediatric ED. This study is modeled closely after an FDA "thorough QT study".

METHODS

EGCs were obtained before and 15, 30, 45, and 60min after a 0.15mg/kg IV dose of ondansetron given for gastroenteritis-associated vomiting. QT intervals were measured manually with digital calipers, and the QTc interval calculated both by Bazett's (QTcB) and Fridericia's (QTcF) correction. A paired t-test comparing QTc was conducted, and frequency of categorical outcomes of prolongation>30msec, >60 msec, and absolute prolongation >450 msec, >480 msec, and >500msec were evaluated.

RESULTS

In a 4-month period, 134 patients were included in the study, 46% were male. The average QTc prior to ondansetron administration was: QTcB 415 msec (95% CI 343-565) and QTcF 373 (95% CI 304-499). The mean difference in QTc after ondansetron was 0.4msec for QTcB (95% CI -35-45msec) and 0.1msec for QTcF (95% CI -40-18msec).

CONCLUSION

In these children, 0.15mg/kg of intravenous ondansetron did not cause prolongation of QTcB or QTcF measured 15min after administration, nor at later times.