[Response to: Preemptive nebulized ketamine for pain control after tonsillectomy in children: randomized controlled trial].

Dear Editor,

We read with great interest the article by Abdel-Ghaffar and colleagues investigating the use of preemptive nebulized ketamine for pain control after tonsillectomy in 100 pediatric patients. These patients reported its effectiveness for post-tonsillectomy pain relief and is an alternative route to intravenous (IV) ketamine. This constitutes a very important advance for tonsillectomy anesthesia, as it may influence the choice of medication administration route and the prevention of inadequately treated postoperative pain, which can lead to dehydration and prolonged hospitalization. It may also be useful to avoid complications caused by systemic opioids and Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), namely respiratory depression, sedation, nausea, vomiting, and bleeding interference.

The primary outcome in the study was the consumption of rescue painkillers in the first 24 hours after surgery. However, we would like to extend the discussion to include postoperative data on sleep quality, another factor that may also be influenced by the use of preemptive nebulized ketamine. Monitoring preoperative and postoperative sleep quality using in-lab polysomnography, for example, could detect any previously non-existent sleep disturbance. This may not only be a consequence of pain, but can also be a causative agent or aggravating factor. Thus, greater sleep efficiency and sleep time can be a sign of improved pain control in the postoperative period, and the bidirectional association of sleep and pain are described.

This could be extended to other common pediatric otorhinolaryngological surgeries, such as adenoidectomy. Studies describing a procedure using nebulized ketamine, similar to that used by Abdel-Ghaffar and colleagues, reported improvements in postoperative pain; however, there is a lack of clinical trials about its postoperative analgesic effects in isolated adenoidectomy, and further studies are required. These could consider the use of sleep quality as an outcome measure.

Despite the important advances made in the understanding of pain mechanisms and management, postoperative pain remains a health care issue, and is associated with a number of adverse effects. Therefore, understanding whether the use of preemptive nebulized ketamine reduces pain following pediatric otorhinolaryngological surgeries is relevant. Nebulized ketamine administration is a relatively recent practice in Medicine, and studies on its analgesic efficiency in tonsillectomy and adenoidectomy are still scarce. Hence, new clinical and experimental studies focusing on these specific associations should evaluate a range of different outcome measures, including postoperative sleep quality. This can help to promote the best choice in the route of the administration of ketamine and contribute to improved recovery and the avoidance of possible complications.

Conflicts of interest

The authors declare no conflicts of interest.