Ketamine impact on intraocular pressure of children: a systematic review and qualitative synthesis of evidence

Introduction: Intraocular pressure (IOP) measuring in children is a defiant challenge for ophthalmologists due to the unwillingness to collaborate of patient; therefore, it is necessary to perform these examinations under anesthesia (EUA) in order to facilitate the measuring. Among the anesthetic drugs, ketamine is safe in both children and adults and different studies have stated that it might have lower impact on IOP than other anesthetic drugs. Objective: To determine whether ketamine has any impact on IOP in pediatric patients. Also, defining if this drug can be recommended to perform EUA in children with glaucoma. Methods: Systematic review of literature was conducted including articles published in Ovid, PubMed, ScienceDirect, Cochrane, and LILACS from January 1970 to February 2019. The studies included were those with patients aged under 18 years to whom ocular tonometry had been performed. Intervention consisted on administering ketamine and the primary outcome to be assessed was changes in IOP after ketamine administration. Intra operative and postoperative complications were also assessed as secondary outcomes. Report is made according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. Results: Nine studies were selected for the systematic review. The administration of ketamine and its effects on intraocular pressure values were described in 293 children. Three studies found rising of intraocular pressure and 6 little or clinically not significant changes. Conclusion: In children, there is low-quality evidence that suggests a minimal impact of ketamine on IOP modification. Better quality studies (controlled clinical trials) are required to clearly recommend the use of ketamine to perform EUA in children with glaucoma.