Dear Editor, We read with interest the article by Banga et al.1 which compares dexmedetomidine–propofol (DP) and ketamine–propofol (KP) sedation in children undergoing cardiac catheterization. While the study addresses an important clinical issue, we would like to raise the following methodological concerns: Firstly, there appears to be a pharmacodynamic mismatch in the analgesic profiles of the regimens. Ketamine provides robust analgesia, whereas dexmedetomidine’s analgesic effect is limited and dose dependent. This imbalance may have influenced intraoperative movement or BIS readings, yet the authors report no difference in fentanyl use or rescue propofol requirements and do not discuss this disparity. Secondly, it is a common clinical practice for femoral vessel puncture to be performed under local anesthetic infiltration by the cardiologist, which reduces nociceptive stimulus. This may have blunted the analgesic demands in both groups and could have altered the rescue dosing. Thirdly, propofol lacks intrinsic analgesic properties. The study would have benefited from incorporating a rescue analgesia protocol using fentanyl in response to hemodynamic or behavioral signs of pain, especially in the DP group. Additionally, a multimodal approach using acetaminophen or NSAIDs could have improved the baseline analgesic regimen. Further, BIS, although useful for assessing hypnotic depth, does not reliably reflect analgesia. In this context, monitoring of depth of anesthesia using entropy—particularly response entropy (RE)2—might have better captured differences in nociceptive response between the two regimens. Then, the study pooled cyanotic and acyanotic congenital heart disease patients. Given the differing hemodynamic physiology and sensitivity to changes in systemic vascular resistance—especially in patients with pulmonary arterial hypertension—the results may not generalize across all congenital heart subgroups.3,4 The hypotensive effect of DP may be less suitable for cyanotic patients and warrants separate analysis. Procedural heterogeneity—diagnostic versus interventional—introduces variability in duration and nociceptive load. The pharmacokinetics of ketamine and dexmedetomidine differ significantly, and a uniform recovery metric without accounting for procedural duration may be misleading. Longer procedures may prolong recovery in the DP group or necessitate supplemental dosing in the KP group. Finally, while bispectral index (BIS) values were significantly lower in the DP group, the similar BIS values in the KP group—despite ketamine’s known effect of artificially elevating BIS—warrant discussion. This discrepancy could have resulted in underestimation of sedation depth in the KP group or unnecessary propofol supplementation. Additionally, the study does not report on antiemetic prophylaxis. Postoperative nausea and vomiting (PONV) can affect 21–35% of patients.5 This is especially important for patients undergoing device closure for intracardiac septal defects. Its absence in the protocol is a significant oversight in a pediatric population. In summary, while the study addresses a pertinent clinical question, several design elements—analgesic equivalence, patient stratification, monitoring modality, and supportive pharmacology—deserve to be highlighted in the limitations for a holistic understanding. Financial Support and Sponsorship Nil. Conflict of interest There are no conflicts of interest.
Bhargava et al. (Wed,) studied this question.