Chris D. Glover

The Effect of Intraoperative Dexmedetomidine on Postoperative Analgesia and Sedation in Pediatric Patients Undergoing Tonsillectomy and Adenoidectomy

BACKGROUND: The immediate postoperative period after tonsillectomy and adenoidectomy, one of the most common pediatric surgical procedures, is often difficult. These children frequently have severe pain but postoperative airway edema along with increased sensitivity to the respiratory-depressant effects of opioids may result in obstructive symptoms and hypoxemia. Opioid consumption may be reduced by nonsteroidal antiinflammatory drugs, but these drugs may be associated with increased bleeding after this operation. Dexmedetomidine has mild analgesic properties, causes sedation without respiratory depression, and does not have an effect on coagulation. We designed a prospective, double-blind, randomized controlled study to determine the effects of intraoperative dexmedetomidine on postoperative recovery including pain, sedation, and hemodynamics in pediatric patients undergoing tonsillectomy and adenoidectomy. METHODS: One hundred nine patients were randomized to receive a single intraoperative dose of dexmedetomidine 0.75 &mgr;g/kg, dexmedetomidine 1 &mgr;g/kg, morphine 50 &mgr;g/kg, or morphine 100 &mgr;g/kg over 10 minutes after endotracheal intubation. RESULTS: There were no significant differences among the 4 groups in patient demographics, ASA physical status, postoperative opioid requirements, sedation scores, duration of oxygen supplementation in the postanesthetic care unit, and time to discharge readiness. The median time to first postoperative rescue analgesic was similar in patients receiving dexmedetomidine 1 &mgr;g/kg and morphine 100 &mgr;g/kg, but significantly longer compared with patients receiving dexmedetomidine 0.75 &mgr;g/kg or morphine 50 &mgr;g/kg (P < 0.01). In addition, the number of patients requiring >1 rescue analgesic dose was significantly higher in the dexmedetomidine 0.75 &mgr;g/kg group compared with the dexmedetomidine 1 &mgr;g/kg and morphine 100 &mgr;g/kg groups, but not the morphine 50 &mgr;g/kg group. Patients receiving dexmedetomidine had significantly slower heart rates in the first 30 minutes after surgery compared with those receiving morphine (P < 0.05). There was no significant difference in sedation scores among the groups. CONCLUSIONS: The total postoperative rescue opioid requirements were similar in tonsillectomy patients receiving intraoperative dexmedetomidine or morphine. However, the use of dexmedetomidine 1 &mgr;g/kg and morphine 100 &mgr;g/kg had the advantages of an increased time to first analgesic and a reduced need for additional rescue analgesia doses, without increasing discharge times.

A multicenter, randomized, double‐blind placebo‐controlled, single dose trial of the safety and efficacy of intravenous ibuprofen for treatment of pain in pediatric patients undergoing tonsillectomy

Tonsillectomy is one of the most common pediatric procedures in the United States. An optimal perioperative pain control regimen remains a challenge. Intravenous ibuprofen administered at induction of anesthesia may be a safe and efficacious option for postoperative tonsillectomy pain.

Neuromonitoring for Scoliosis Surgery

The use of intraoperative neuromonitoring (IONM) during pediatric scoliosis repair has become commonplace to reduce the risk of potentially devastating postoperative neurologic deficits. IONM techniques include somatosensory evoked potentials, motor evoked potentials, electromyography, and intraoperative wake-up tests. Special considerations for scoliosis repair in pediatric patients include preexisting neurologic deficits and young patients with immature neural pathways in whom neurophysiologic monitoring may prove difficult or unreliable.

Comparison of the development of performance skills in ultrasound-guided regional anesthesia simulations with different phantom models.

Background Ultrasound-guided regional anesthesia (UGRA) skills are traditionally obtained by supervised performance on patients, but practice on phantom models improves success. Currently available models are expensive or use perishable products, for example, olive-in-chicken breasts (OCB). We constructed 2 inexpensive phantom (transparent and opaque) models with readily available nonperishable products and compared the process of learning UGRA skills by novice practitioners on these models with the OCB model. Methods Three experts first established criteria for a satisfactory completion of the simulated UGRA task in the 3 models. Thirty-six novice trainees (<20 previous UGRA experience) were randomly assigned to perform a UGRA task on 1 of 3 models—the transparent, opaque, and OCB models, where the hyperechoic target was identified, a needle was advanced to it under ultrasound guidance, fluid was injected, and images were saved. We recorded the errors during task completion, number of attempts and needle passes, and the time for target identification and needle placement until the predetermined benchmark of 3 consecutive successful UGRA simulations was accomplished. Results The number of errors, needle passes, and time for task completion per attempt progressively decreased in all 3 groups. However, failure to identify the target and to visualize the needle on the ultrasound image occurred more frequently with the OCB model. The time to complete simulator training was shortest with the transparent model, owing to shorter target identification times. However, trainees were less likely to agree strongly that this model was realistic for teaching UGRA skills. Conclusions Training on inexpensive synthetic simulation models with no perishable products permits learning of UGRA skills by novices. The OCB model has disadvantages of containing potentially infective material, requires refrigeration, cannot be used after multiple needle punctures, and is associated with more failures during simulated UGRA. Direct visualization of the target in the transparent model allows the trainee to focus on needle insertion skills, but the opaque model may be more realistic for learning target identification skills required when UGRA is performed on real patients in the operating room.

Perioperative Outcomes and Management in Pediatric Complex Cranial Vault Reconstruction: A Multicenter Study from the Pediatric Craniofacial Collaborative Group

Background: The Pediatric Craniofacial Collaborative Group established the Pediatric Craniofacial Surgery Perioperative Registry to elucidate practices and outcomes in children with craniosynostosis undergoing complex cranial vault reconstruction and inform quality improvement efforts. The aim of this study is to determine perioperative management, outcomes, and complications in children undergoing complex cranial vault reconstruction across North America and to delineate salient features of current practices. Methods: Thirty-one institutions contributed data from June 2012 to September 2015. Data extracted included demographics, perioperative management, length of stay, laboratory results, and blood management techniques employed. Complications and outlier events were described. Outcomes analyzed included total blood donor exposures, intraoperative and perioperative transfusion volumes, and length of stay outcomes. Results: One thousand two hundred twenty-three cases were analyzed: 935 children aged less than or equal to 24 months and 288 children aged more than 24 months. Ninety-five percent of children aged less than or equal to 24 months and 79% of children aged more than 24 months received at least one transfusion. There were no deaths. Notable complications included cardiac arrest, postoperative seizures, unplanned postoperative mechanical ventilation, large-volume transfusion, and unplanned second surgeries. Utilization of blood conservation techniques was highly variable. Conclusions: The authors present a comprehensive description of perioperative management, outcomes, and complications from a large group of North American children undergoing complex cranial vault reconstruction. Transfusion remains the rule for the vast majority of patients. The occurrence of numerous significant complications together with large variability in perioperative management and outcomes suggest targets for improvement.

Postoperative pain and the use of ultrasound-guided regional analgesia in pediatric supracondylar humerus fractures.

A total of 230 children undergoing closed reduction and percutaneous pinning of supracondylar humerus fractures were analyzed retrospectively. Severe pain (score≥7/10) was reported in 10% of general anesthesia-only patients in the postanesthesia care unit and in 28% of the 130 admitted patients. The 36 patients who received ultrasound-guided regional analgesia+general anesthesia had decreased intraoperative opioid consumption and postanesthesia care unit pain scores. After admission, pain scores and opioid consumption did not differ between fracture and anesthesia types. No patient developed compartment syndrome. Severe pain is frequent after closed reduction and percutaneous pinning of supracondylar humerus fractures. Further study of ultrasound-guided regional analgesia is needed.

Treatment effects of dexmedetomidine and ketamine on postoperative analgesia after cleft palate repair.

Primary cleft palate repair may result in significant pain in the immediate postoperative period, which can lead to vigorous crying resulting in wound dehiscence and pulmonary complications. Effective pain control with opioids is the mainstay but administration on the floor has to be countered with the complications associated with their use, chiefly respiratory depression and sedation. We retrospectively examined the efficacies of intraoperative administration of intravenous (IV) dexmedetomidine (DEX) and ketamine (KET) to prevent early postoperative pain in children undergoing primary cleft palate repair and compared the results against relevant literature. The Texas Childrens Hospital anesthesia database was queried to identify children undergoing a palatal surgery from December 2011 to December 2012. Inclusion criteria permitted completed primary palatal surgery without major complications and intraoperative administration of DEX or KET. The control group (CTRL) received no additional drug. A comprehensive literature review was performed. A total of 71 pediatric patients underwent palatal surgery during the study period with 46 patients qualifying for analysis. Although results were not significant, consistent trends were observed with regards to lower opioid requirements during the first 24 hours for both medications compared with the CTRL. KET also had shorter time to discharge. The literature review resulted in several studies supporting decreased postoperative pain end points for both DEX and KET. In our sample, DEX and KET reduced postoperative opioid requirements. KET seems to have the added benefit of a shorter hospital stay. These finding are supported in the literature. With further investigation, the addition of these drugs may serve to provide improved pain relief without over sedation in patients undergoing cleft palate repair.

Symptomatic postsurgical cerebrospinal fluid leak treated by aspiration and epidural blood patch under ultrasound guidance in 2 adolescents

Cerebrospinal fluid leakage causing a pseudomeningocele is a well-recognized complication after spine surgery. The repair of pseudomeningocele in a symptomatic patient is usually accomplished with direct open surgical repair of the durotomy, prolonged lumbar drainage, and/or placement of an epidural blood patch. The authors highlight a unique method of pseudomeningocele repair by presenting 2 cases of adolescent girls with symptomatic lumbar pseudomeningoceles. In both cases ultrasound was used to guide the aspiration of CSF from each pseudomeningocele and to apply the epidural blood patch. Both patients had complete and immediate resolution of symptoms. The authors found ultrasound to be a useful tool to assess the extent of the CSF leakage, to determine the degree of aspiration of the extradural CSF, and to confirm the injection of the blood into the epidural space and the space created by the pseudomeningocele.

Safety of antifibrinolytics in cranial vault reconstructive surgery: a report from the pediatric craniofacial collaborative group

Antifibrinolytic therapy significantly decreases blood loss and transfusion in pediatric cranial vault reconstructive surgery; however, concern regarding the side effects profile limits clinical use.

CYP2D6 pharmacogenetic and oxycodone pharmacokinetic association study in pediatric surgical patients

AIM Oxycodone is partly metabolized to the active metabolite oxymorphone by hepatic CYP2D6 in the liver. Significant genetic variability in CYP2D6 activity affects oxymorphone formation. This study aimed to associate CYP2D6 genotype and oxycodones metabolism. METHODS 30 children were administered oral oxycodone postoperatively. Plasma levels of oxycodone and oxymorphone, and CYP2D6 genotype were analyzed. CYP2D6 genotype and oxycodone metabolism phenotype were determined based on CYP2D6 total activity score (TAS) and metabolism phenotype: poor metabolizer (PM), intermediate metabolizer (IM), extensive metabolizer (EM) or ultrarapid metabolizer (UM). RESULTS Compared with PM/IM subjects, significantly greater oxymorphone exposure was seen in EM subjects (p = 0.02 for Cmax, p = 0.016 for AUC0-6 and p = 0.026 for AUC0-24). Similarly, higher TAS value was found to be associated with greater oxymorphone exposure. Higher conversion of oxycodone to oxymorphone was observed in EM subjects compared with PM/IM subjects (p = 0.0007 for Cmax, p = 0.001 for AUC0-6 and p = 0.004 for AUC0-24). CONCLUSION CYP2D6 phenotypes explain metabolism of oxycodone in children, and oxymorphone exposure is higher in CYP2D6 EM phenotype. Further studies are needed to predict the occurrence of adverse event and tailor oxycodone dose for a specific CYP2D6 phenotype.