Procedural sedation（镇静） and analgesia（止痛） is an essential element of care for children requiring painful procedures in the emergency department. The practice of combining ketamine（克他命） and propofol（异丙酚） , two common medications used in emergency departments, has become more popular. However, until recently, it was unclear whether this practice was superior to the use of either agent alone, especially in children. Research led by Drs. Amit Shah, Gregory Mosdossy and Michael Rieder of the Schulich School of Medicine & Dentistry at The University of Western Ontario and Lawson Health Research Institute provides evidence that when compared to ketamine alone, patients who receive a combination of ketamine and propofol have a slightly faster recovery time and suffer from less severe side effects.

The study, published online in the Annals of Emergency Medicine, included 136 children treated at London Health Sciences Centre's Children's Hospital.

Ketamine is well established as a safe and effective solitary agent for procedural sedation and analgesia（止痛） . However, it is known to cause adverse side effects, such as vomiting. Propofol is associated with a dose-dependent risk of respiratory（呼吸的） depression, but has less severe side effects.

It has been theorized that by combining the two agents, you can decrease the dose requirement of both agents thereby reducing the negative side-effects, but still have a safe and effective analgesia.

This is the first large well-conducted study exploring the use of ketamine-propofol for children in the Paediatric Emergency Department. Previous studies had hinted at its advantage but up until now results were not conclusive.

"Our study found that ketamine-propofol is an effective combination for pediatric（小儿科的） procedural sedation, providing a slightly shorter total sedation time than ketamine alone, with less adverse events and higher satisfaction scores," says Dr. Shah. "We believe this study provides evidence for a safe and effective alternative sedation regimen for children in the Emergency Department and may lead to a change in sedation practices in other hospitals."