Joel B. Gunter

A comparison of dexmedetomidine with propofol for magnetic resonance imaging sleep studies in children.

BACKGROUND:Magnetic resonance imaging (MRI) sleep studies can be used to guide management of children with obstructive sleep apnea (OSA) refractory to conservative therapy. Because children with OSA are sensitive to the respiratory-depressant effects of sedatives and anesthetics, provision of anesthesia for imaging studies in this patient population can be challenging. Dexmedetomidine has been shown to have pharmacological properties simulating natural sleep with minimal respiratory depression. We hypothesized that, compared with propofol, dexmedetomidine would have less effect on upper airway tone and airway collapsibility, provide more favorable conditions during dynamic MRI airway imaging in children with OSA, have fewer scan interruptions, and require less aggressive airway interventions. METHODS:In this retrospective descriptive study, we reviewed the records of 52 children receiving dexmedetomidine and 30 children receiving propofol for anesthesia during MRI sleep studies between July 2006 and March 2008. Documentation of the severity of OSA by overnight polysomnography was available for 67 of the 82 subjects, who were analyzed separately. Data analyzed included demographics, severity of OSA, comorbidities, hemodynamic changes, use of artificial airways, additional airway maneuvers, and successful completion of the MRI scan. RESULTS:Demographics, OSA severity by polysomnography, anesthetic induction, and baseline hemodynamics were comparable in both groups. An interpretable MRI sleep study was obtained for 98% of children in the dexmedetomidine group and 100% in the propofol group. Of 82 children, MRI sleep studies were successfully completed without the use of artificial airways in 46 children (88.5%) in the dexmedetomidine group versus 21 children (70%) in the propofol group (P = 0.03). An artificial airway was required to complete the study in five children (12%) in the dexmedetomidine group versus nine children (35%) in the propofol group (P = 0.06). Additional airway maneuvers (chin lift and shoulder roll) were required to complete the study in one child (2%) in the dexmedetomidine group and three children (10%) in the propofol group (P = 0.14). Children in the dexmedetomidine group experienced reductions in heart rate, whereas those in the propofol group experienced reductions in arterial blood pressure; these reductions were statistically, but not clinically, significant. CONCLUSIONS: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.

An evaluation of the efficacy and tolerability of oral tramadol hydrochloride tablets for the treatment of postsurgical pain in children.

In this double-blinded, randomized, multicenter study, we examined analgesic efficacy and tolerability of tramadol in postoperative pediatric patients. Eighty-one postsurgical ASA physical status I and II patients ages 7–16 yr received oral tramadol (approximately 1 or 2 mg/kg) for postoperative analgesia when they were ready to transition from morphine patient-controlled analgesia to oral analgesics. Rescue analgesia consisted of morphine patient-controlled analgesia or an oral equivalent dose of oxycodone. Patients rated their pain just before the administration of tramadol and at regular intervals for 8 h afterwards using the Wong-Baker Faces Pain Rating Scale. The 2-mg/kg group required approximately half as much rescue analgesia as the 1-mg/kg group (P = 0.006). Parents rated the larger dose more favorably. Adverse events were generally mild to moderate in severity (vomiting [10%], nausea [9%], pruritus [7%], rash [4%]) and similar between the two treatment groups. There were no significant changes in hemodynamic variables, respiratory rate, or Spo2 percentages between the two treatment groups or in all patients compared with pretreatment values.

Effect of increasing depth of dexmedetomidine anesthesia on upper airway morphology in children

Objective:  This prospective study examines the dose–response effects of dexmedetomidine on upper airway morphology in children with no obstructive sleep apnea (OSA).

Real-Time Assessment of Perioperative Behaviors and Prediction of Perioperative Outcomes

Background and Aims: New onset maladaptive behaviors, such as temper tantrums, nightmares, bed-wetting, attention-seeking, and fear of being alone are common in children after outpatient surgery. Preoperative anxiety, fear and distress behaviors of children predict postoperative maladaptive behaviors as well as emergence delirium. Parental anxiety has also been found to influence children’s preoperative anxiety. Currently, there is no real-time and feasible tool to effectively measure perioperative behaviors of children and parents. We developed a simple and real-time scale, the Perioperative Adult Child Behavioral Interaction Scale (PACBIS) to assess perioperative child and parent behaviors that might predict postoperative problematic behavior and emergence excitement. METHODS: We used the PACBIS to evaluate perioperative behaviors during anesthetic induction and recovery in a sample of 89 children undergoing tonsillectomies and adenoidectomies, and their parents. Preoperative anxiety with the modified Yale Preoperative Anxiety Scale, compliance with induction of anesthesia with Induction Compliance Checklist, and incidence of emergence excitement were also recorded. RESULTS: The PACBIS demonstrated good concurrent validity with modified Yale Preoperative Anxiety Scale and Induction Compliance Checklist and predicted postanesthetic emergence excitement. DISCUSSION: The PACBIS is the first real-time scoring instrument that evaluates children’s and parents’ perioperative behavior. The specific behaviors identified by the PACBIS might provide targets for interventions to improve perioperative experiences and postoperative outcomes.

Factors predictive of poor behavioral compliance during inhaled induction in children.

BACKGROUND: Preoperative identification of children at risk of emotional distress and poor behavioral compliance during inhaled induction of anesthesia allows targeted interventions to reduce distress, thereby enhancing the quality of the anesthetic experience. We sought to identify patient, procedural, and health care system factors predictive of poor behavioral compliance during induction. METHODS: We studied 861 developmentally appropriate children ages 1–13 yr, The American Society of Anesthesiologists physical status I to III, presenting for inhaled induction of anesthesia. All inductions were performed in an induction room with parent(s) present. Behavioral compliance was assessed using the Induction Compliance Checklist (ICC), an observational scale consisting of 10 behaviors scored as the number of behaviors observed during induction; ICC ≥4 was considered poor behavioral compliance. A multivariable ordinal logistic regression model for behavioral compliance was generated and the performance of the multivariable model was evaluated by the c statistic. RESULTS: Twenty-one percent of children exhibited poor behavioral compliance on induction. Factors increasing the odds of poor behavioral compliance were younger age (<4 yr, P < 0.0001), shorter preoperative preparation time (P = 0.004), and high anxiety levels in the preoperative clinic (modified-Yale preoperative anxiety scale >40; P = 0.016). Previous anesthesia experience increased the odds in school-age children (P = 0.046); this effect was ameliorated in children attending the preoperative tour (P = 0.018). The model using these factors demonstrated moderate discrimination between children with poor compliance and those with perfect compliance (ICC = 0) (c statistic = 0.75). CONCLUSIONS: 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.

Trending and Accuracy of Noninvasive Hemoglobin Monitoring in Pediatric Perioperative Patients

BACKGROUND:Rainbow Pulse CO-Oximetry technology® (Masimo Corporation, Irvine, CA) provides continuous and noninvasive measurement of arterial hemoglobin concentration (SpHb). We assessed the trending and accuracy of SpHb by this innovative monitoring compared with Hb concentration obtained with conventional laboratory techniques (Hb) in children undergoing surgical procedures with potential for substantial blood loss. METHODS:Hb concentrations were recorded from Pulse CO-Oximetry and a conventional hematology analyzer. Regression analysis and 4-quadrant plot were used to evaluate the trending for changes in SpHb and Hb measurements (&Dgr;SpHb and &Dgr;Hb). Bias, precision, and limits of agreement of SpHb and of in vivo adjusted SpHb (SpHb − first bias to HB) compared with Hb were calculated. RESULTS:One hundred fifty-eight SpHb–Hb data pairs and 105 delta pairs (&Dgr;SpHb and &Dgr;Hb) from 46 patients aged 2 months to 17 years with Hb ranging from 16.7 to 7.9 g/dL were collected. To evaluate trending, the delta pairs (&Dgr;SpHb and &Dgr;Hb) were plotted, which revealed a positive correlation (&Dgr;SpHb = 0.022 + 0.76&Dgr;Hb) with correlation coefficient r = 0.76, 95% CI [confidence interval] = 0.57–0.86. The bias and precision of SpHb to Hb and in vivo adjusted SpHb were 0.4 ± 1.3 g/dL and 0.1 ± 1.2 g/dL, respectively; the limits of agreement were −2.0 to 3.2 g/dL before in vivo adjustment and −2.4 to 2.2 g/dL after in vivo adjustment (P value = 0.04). The mean percent bias (from the reference Hb concentration) decreased from 4.1% ± 11.9% to 0.7% ± 11.3% (P value = 0.01). No drift in bias over time was observed during the study procedure. Of patient demographic and physiological factors tested for correlation with the SpHb, only perfusion index at sensor site showed a weak correlation. CONCLUSIONS:The accuracy of SpHb in children with normal Hb and mild anemia is similar to that previously reported in adults and is independent of patient demographic and physiological states except for a weak correlation with perfusion index. The trending of SpHb and Hb in children with normal Hb and mild anemia showed a positive correlation. Further studies are necessary in children with moderate and severe anemia.

Real-Time Assessment of Perioperative Behaviors in Children and Parents: Development and Validation of the Perioperative Adult Child Behavioral Interaction Scale

BACKGROUND:Behavior in response to distressful events during outpatient pediatric surgery can contribute to postoperative maladaptive behaviors, such as temper tantrums, nightmares, bed-wetting, and attention seeking. Currently available perioperative behavioral assessment tools have limited utility in guiding interventions to ameliorate maladaptive behaviors because they cannot be used in real time, are only intended to be used during 1 phase of the experience (e.g., perioperative), or provide only a static assessment of the child (e.g., level of anxiety). A simple, reliable, real-time tool is needed to appropriately identify children and parents whose behaviors in response to distressful events at any point in the perioperative continuum could benefit from timely behavioral intervention. Our specific aims were to (1) refine the Perioperative Adult Child Behavioral Interaction Scale (PACBIS) to improve its reliability in identifying perioperative behaviors and (2) validate the refined PACBIS against several established instruments. METHODS:The PACBIS was used to assess the perioperative behaviors of 89 children aged 3 to 12 years presenting for adenotonsillectomy and their parents. Assessments using the PACBIS were made during perioperative events likely to prove distressing to children and/or parents (perioperative measurement of blood pressure, induction of anesthesia, and removal of the IV catheter before discharge). Static measurements of perioperative anxiety and behavioral compliance during anesthetic induction were made using the modified Yale Preoperative Anxiety Scale and the Induction Compliance Checklist (ICC). Each event was videotaped for later scoring using the Child-Adult Medical Procedure Interaction Scale-Short Form (CAMPIS-SF) and Observational Scale of Behavioral Distress (OSBD). Interrater reliability using linear weighted kappa (&kgr;w) and multiple validations using Spearman correlation coefficients were analyzed. RESULTS:The PACBIS demonstrated good to excellent interrater reliability, with &kgr;w ranging from 0.62 to 0.94. The Child Coping and Child Distress subscores of the PACBIS demonstrated strong concurrent correlations with the modified Yale Preoperative Anxiety Scale, ICC, CAMPIS-SF, and OSBD. The Parent Positive subscore of the PACBIS correlated strongly with the CAMPIS-SF and OSBD, whereas the Parent Negative subscore showed significant correlation with the ICC. The PACBIS has strong construct and predictive validities. CONCLUSIONS:The PACBIS is a simple, easy to use, real-time instrument to evaluate perioperative behaviors of both children and parents. It has good to excellent interrater reliability and strong concurrent validity against currently accepted scales. The PACBIS offers a means to identify maladaptive child or parental behaviors in real time, making it possible to intervene to modify such behaviors in a timely fashion.

To Pretreat or Not to Pretreat: Prophylactic Anticholinergic Administration Before Dexmedetomidine in Pediatric Imaging.

BACKGROUND:Dexmedetomidine (Dex) appears to be very effective as a sole sedative for pediatric imaging when used at high doses, but at an increased risk of transient hypertension, hypotension, and bradycardia. There are no clinical evidence/guidelines to guide anesthesia providers as to whether patients should be pretreated with an anticholinergic. The aim of this study was to demonstrate the changes in hemodynamic parameters after Dex sedation attributed to receiving or not receiving an anticholinergic pretreatment and compare for any differences or similarities. A subgroups analysis was performed in children with Down syndrome (DS). METHODS:In this retrospective descriptive study, we reviewed the records of 163 children receiving Dex anesthesia during MRI studies. Data analyzed included demographics, history of DS, and hemodynamics (heart rate [HR], systolic blood pressure [SBP], and diastolic blood pressure [DBP]) following Dex loading and infusion and the administration of an anticholinergic (atropine or glycopyrrolate). RESULTS:The mean age was 94.5 months, and 52 (32%) patients had DS. The generalized linear mixed-effects regression model showed a significant reduction in HR and SBP in all patients when no anticholinergic was administered compared with when it was administered. There was no significant change with DBP. During the scan period, the HR of the no-anticholinergic group decreased 26.6%, whereas that of the anticholinergic group decreased by only 16.7% from baseline (P < 0.01). The maximal SBP increased by a significantly greater percentage, compared with baseline, in the anticholinergic group in comparison with the no-anticholinergic group (20.2% vs 10.4%, respectively; P = 0.02). In the DS group, the difference in the maximal SBP change during the scan period was exaggerated, with a percentage increase that was 36 times larger in the anticholinergic group compared with the no-anticholinergic group (22% vs 0.6%, respectively; P< 0.01). CONCLUSIONS:Administration of a prophylactic anticholinergic with Dex shows no advantage other than a transient clinically insignificant increase in HR and SBP, and it may precipitate transient exaggerated SBP in more patients compared with not using a prophylactic anticholinergic.