Dexmedetomidine provided an acceptable level of anesthesia for MRI sleep studies in children with OSA, producing a high yield of interpretable studies of the patient's native airway. The need for artificial airway support during the MRI sleep study was significantly less with dexmedetomidine than with propofol. Dexmedetomidine may be the preferred drug for anesthesia during MRI sleep studies in children with a history of severe OSA and may offer benefits to children with sleep-disordered breathing requiring anesthesia or anesthesia for other diagnostic imaging studies.

Regional anesthesia has become a routine part of the practice of anesthesiology in infants and children. Local anesthetic toxicity is extremely rare in infants and children; however, seizures, dysrhythmias, cardiovascular collapse, and transient neuropathic symptoms have been reported. Infants and children may be at increased risk from local anesthetics compared with adults. Larger volumes of local anesthetics are used for epidural anesthesia in infants and children than in adults. Metabolism and elimination of local anesthetics can be delayed in neonates, who also have decreased plasma concentrations of alpha(1)-acid glycoprotein, leading to increased concentrations of unbound bupivacaine. Most regional anesthetic procedures in infants and children are performed with the patient heavily sedated or anesthetized; because of this, and because a test dose is not a particularly sensitive marker of intravenous injection in the anesthetized patient, detection of intravascular local anesthetic injection is extremely difficult. The same local anesthetics used in adult anesthetic practice are also used in infants and children. Because of its extremely short duration of action, chloroprocaine has been used primarily for continuous epidural techniques in infants and children. The use of tetracaine has generally been limited to spinal and topical anesthesia. Lidocaine (lignocaine) has been used extensively in infants and children for topical, regional, plexus, epidural and spinal anesthesia. The association between prilocaine and methemoglobinemia has generally restricted prilocaine use in infants and children to the eutectic mixture of local anesthetics (EMLA). Because of its greater degree of motor block compared with other long-acting local anesthetics, etidocaine has generally been limited to plexus blocks in infants and children. Mepivacaine has been used for both plexus and epidural anesthesia in infants and children. Because postoperative analgesia is often the primary justification for regional anesthesia in infants and children, bupivacaine, a long-acting local anesthetic, is the most commonly reported local anesthetic for pediatric regional anesthesia. Given the lower toxic threshold of bupivacaine compared with other local anesthetics, the risk-benefit ratio of bupivacaine may be greater than that of other local anesthetics. Two new enantiomerically pure local anesthetics, ropivacaine and levobupivacaine, offer clinical profiles comparable to that of bupivacaine but without its lower toxic threshold. The extreme rarity of major toxicity from local anesthetics suggests that widespread replacement of bupivacaine with ropivacaine or levobupivacaine is probably not necessary. However, there are clinical situations, including prolonged local anesthetic infusions, use in neonates, impaired hepatic metabolic function, and anesthetic techniques requiring a large mass of local anesthetic, where replacement of bupivacaine with ropivacaine, levobupivacaine or (for continuous techniques) chloroprocaine appears prudent.

Three different vasoconstricting agents were evaluated during functional endoscopic sinus surgery (FESS) in 57 children. Oxymetazoline hydrochloride 0.05%, phenylephrine hydrochloride 0.25%, or cocaine 4% was applied to the nasal mucosa in a prospective, randomized, double-blind fashion. Heart rate and blood pressure changes were recorded 5 and 10 minutes after application of the study vasoconstrictor to each nostril. The surgeon's subjective impressions of bleeding and visualization were recorded for each side of the nose, as were total blood loss and anesthesia time. Although all three vasoconstrictors were tolerated well by the children, there was a suggestion that heart rate decreased more at 5 minutes with phenylephrine than with oxymetazoline or cocaine (P = .08) and that blood pressure increased more at 10 minutes with phenylephrine than with oxymetazoline or cocaine (P = .1). No arrhythmias were noted. Subjective scoring for bleeding showed that children receiving oxymetazoline were less likely to receive scores of "more" bleeding than usual (3/38 vs. 10/34 for phenylephrine and 10/35 for cocaine, P less than .02). Subjective scoring for visualization showed that children receiving oxymetazoline were also less likely to receive scores of "worse" visualization than usual (3/38 vs. 12/38 for phenylephrine and 9/35 for cocaine, P less than .01). There was no difference in surgical bleeding or visualization between children receiving phenylephrine and children receiving cocaine. In our institution, 0.05% oxymetazoline is the preferred vasoconstrictor for FESS in children.

Factors predictive of poor behavioral compliance were age, previous anesthesia, preoperative tour attendance, preoperative preparation time and anxiety levels in the preoperative clinic. These factors, bundled into a predictive algorithm, may help identify children who could benefit from behavioral or pharmacological interventions and avoid use of interventions to those at low risk.

Upper airway changes associated with increasing doses of dexmedetomidine in children with no OSA are small in magnitude and do not appear to be associated with clinical signs of airway obstruction. Even though these changes are small, all precautions to manage airway obstruction should be taken when dexmedetomidine is used for sedation.