Efficacy and safety of atropine-midazolam-ketamine in pediatric oncology patients

This study assessed the efficacy and safety of atropine-midazolamketamine a s a sedative or analgesic regimen in pediatric oncology patients undergoing painful procedures. Of 136 consecutive pediatric patients undergoing painf ul procedures from June 1, 1997 to June 30, 1998, 69 patients (39 males and 30 females; mean age, 7.3 +/- 4.4 years) underwent 255 procedures using in travenous atropine 0.01 mg/kg plus midazolam 0.05 mg/kg plus ketamine up to 2.0 mg/ kg. Sedation monitoring forms for these 69 patients were examined retrospectively. Vital signs, pulse oximetry, patient status, clinical effe cts, adverse events, and patient or parent comments were recorded at 5-minu te intervals from initiation of sedation until the child was awake. Clinica l efficacy was defined as procedure completion with minimal patient distres s; a clinically significant adverse event was defined as baseline deviation requiring acute medical intervention to prevent or ameliorate clinical det erioration. Transient clinical effects were defined as self-limited deviati ons in respiratory rate, heart rate, or blood pressure,15% of age-specific norms. Most of the participants were white males with leukemia or lymphoma who were undergoing lumbar punctures. Twenty-three procedures (9.0%) requir ed additional administration of midazolam or ketamine for pain control or s edation. The 3 most frequent transient effects were hypertension in 71 proc edures (27.8%), hypotension in 53 procedures (20.8%), and tachycardia in 49 procedures (19.2%). Twenty-five procedures (9.8%) had associated complicat ions. Ten procedures (3.9%) had ketamine-associated emergent reactions, ran ging from laughing and verbosity to screaming and crying. Nine procedures ( 3.5%) were associated with nausea, vomiting, or dry heaving, and 2 (0.8%) w ere associated with shaking chills after procedure completion. The clinical ly significant adverse event rate was 1.6% (n = 4, all during lumbar punctu res). In 1 case, the procedure was terminated prematurely because of laryng ospasm; in 3 cases oxygen supplementation was required because of hypoxemia . Clinically significant adverse events were associated with younger patien ts and increased ketamine doses. None of the adverse events had long-term s equelae, Results of the present study suggest that the atropine-midazolam-k etamine regimen is efficacious and demonstrates an acceptable safety profil e in the majority of pediatric oncology patients undergoing properly superv ised sedation.