Jeannie Zuk

Correlation of abdominal site near-infrared spectroscopy with gastric tonometry in infants following surgery for congenital heart disease.

Objective: Splanchnic oximetry, as measured by near-infrared spectroscopy (NIRS), correlates with gastric tonometry as a means of assessing regional (splanchnic) oxygenation and perfusion. Design: Prospective, data-gathering study. Setting: Pediatric cardiac intensive care unit in a tertiary care children’s hospital. Subjects: Neonates and infants with congenital heart disease who underwent catheter intervention or surgical repair requiring cardiopulmonary bypass. Interventions: None. Measurements and Main Results: Twenty neonates and infants were studied within 48 hrs of surgery. We measured somatic saturation (rSO2) via NIRS sensors placed over the anterior abdomen (splanchnic bed) and dorsal lateral flank (renal bed). Somatic rSO2 readings were paired with simultaneous points of intramucosal gastric pH (pHi), measured by tonometry. The rSO2 readings were paired with serum lactate and measurements of systemic mixed venous saturation (S&OV0456;o2). There was strong correlation between the abdominal rSO2 and pHi (r = .79; p < .0001) as well as between abdominal rSO2 and S&OV0456;o2 (r = .89; p < .0001). There was also significant negative correlation between the abdominal rSO2 and serum lactate (r = .77; p < .0001). Correlations between the dorsal lateral (renal) rSO2 measurements and serum lactate and S&OV0456;o2 were also significant but not as strong. Conclusions: Abdominal site rSO2, measured in infants with either single or biventricular physiology, exhibits a strong correlation with gastric pHi as well as with serum lactate and S&OV0456;o2. The results indicate that rSO2 measurements over the anterior abdominal wall correlate more strongly than flank rSO2 with regard to systemic indices of oxygenation and perfusion. This study suggests that the NIRS monitor is a valid modality to obtain an easy, immediate, and noninvasive measurement of splanchnic rSO2 in infants following cardiac surgery for congenital heart disease.

Sedation, analgesia, and neuromuscular blockade in the pediatric intensive care unit: survey of fellowship training programs.

Objective: To survey current sedation, analgesia, and neuromuscular blockade practices in pediatric critical care fellowship training programs in the United States. Design: Questionnaire survey sent by E-mail to all program directors. The survey could be submitted either via a Web site, fax, or mail. Setting: University school of medicine. Subjects: Fifty-nine pediatric critical care fellowship training program directors in the United States, listed on the Accreditation Council for Graduate Medical Education Web site. Interventions: Survey. Measurements and Main Results: The response rate was 59.3% (35 questionnaires). Midazolam, lorazepam, morphine, and fentanyl are the most frequently used drugs in pediatric intensive care units for analgesia and sedation. Most pediatric intensive care units surveyed have a written sedation policy (66%). The majority of units responding to the survey (85.7%) routinely use a scoring system to assess agitation and pain in children, with the most common being the COMFORT score. All of the pediatric intensive care units surveyed reported weaning drugs slowly to try to prevent drug withdrawal. Movement disorders related to prolonged sedation and analgesia seem to be more common than is reported in the literature, with 65.7% of units reporting cases. There is good consensus on the indications for neuromuscular blockade, with vecuronium being the most popular drug. Conclusions: When compared with a similar survey from 1989, this survey suggests that pediatric critical care units with fellowship training programs have made some changes in their approach to sedation and analgesia over the past decade. More fellowship directors report the use of sedation protocols and better recognition, prevention, and management of drug withdrawal. Similar analgesic, sedative, and neuromuscular blocking drugs are being used but some more commonly than a decade ago.

Hypnotic Depth and the Incidence of Emergence Agitation and Negative Postoperative Behavioral Changes

Background:  Emergence agitation (EA) and negative postoperative behavioral changes (NPOBC) are common in children, although the etiology remains unclear. We investigated whether longer times under deep hypnosis as measured by Bispectral Index™ (BIS) monitoring would positively correlate with a greater incidence of EA in the PACU and a greater occurrence of NPOBC in children after discharge.

The incidence of intraoperative awareness in children: childhood awareness and recall evaluation.

BACKGROUND: There is a considerable discrepancy between the reported incidences of awareness under anesthesia in children (0.2%–2.7%). In this prospective, observational, cohort study we evaluated 1) the incidence of awareness during general anesthesia in children across three settings, 2) factors contributing to awareness, and 3) short-term psychological effects of awareness. METHODS: Children (aged 5–15 yr) who underwent general anesthesia were included, and all perioperative data including anesthetic drugs were collected prospectively. Children were interviewed three times postoperatively using a semistructured questionnaire. All cases of possible or probable awareness were discussed with the childs care providers to confirm or refute the memories. Internal consensus among investigators across sites was reached, and these cases and a random selection of others were reviewed by three external reviewers. For the purpose of this study, possible/probable awareness was defined as cases with agreement between the internal consensus and at least two of the three external reviewers. RESULTS: One thousand seven hundred eighty-four children completed at least one interview. Thirty-two cases were coded as possible or probable awareness by at least one entity (i.e., either the internal consensus or one of the external reviewers). Fourteen of these cases met the definition for possible/probable awareness, making the incidence of awareness 0.8%. Six of the 14 children with awareness (43%) remembered feeling scared during their surgery and three (21%) reported hurting. Two children in this group (14%) said they would feel worse if they had to have surgery again, which was not significantly different from reports of children with no recall (15%). None of the children with awareness required psychological follow-up. Endoscopic procedures were associated with a higher risk for awareness (relative risk = 4.5 [confidence interval 1.5–13.6]). CONCLUSIONS: Although 0.8% of children experienced possible/probable awareness in this study, none experienced short-term psychological distress.

Pharmacokinetics of Single-Dose Intravenous Ketorolac in Infants Aged 2-11 Months

BACKGROUND:Ketorolac is a parenterally available nonsteroidal antiinflammatory drug that nonselectively inhibits cyclooxygenase. Ketorolac is an attractive alternative to opioids in the pediatric population because of its favorable side effect profile; it provides postoperative analgesia similar to morphine, but is associated with significantly less respiratory depression, pruritus, and emesis. Despite the efficacy of ketorolac in young patients, there are minimal data to characterize the pharmacokinetic variables of ketorolac in infants younger than 6 months. METHODS:In this study, 17 infants younger than 1 year old, without renal or liver disease, undergoing elective surgery received a single-dose of IV ketorolac 0.5 mg/kg. Blood was sampled at 0, 5, 10, 15, 30, 60, and 120 minutes, and at 4, 6, 12, and 24 hours. Ketorolac levels were analyzed using a specific and validated high-performance liquid chromatography method with mass spectrometry (LC-LC/MS/MS). Pharmacokinetic analysis of individual subjects and population pharmacokinetic modeling was performed using SAAM II and PopKinetics, respectively (SAAM Institute, University of Washington). RESULTS:Characterization of pharmacokinetic parameters was possible in 14 subjects. The data were best described by a 2-compartment model. Estimated individual parameters were clearance 1.49 ± 1.12 mL/min/kg, Vss (volume of distribution at steady state) 0.31 ± 0.11 L/kg, and half-life of 236 ± 169 minutes. Estimated population pharmacokinetic parameters were clearance 1.52 mL/min/kg and Vss 0.29 L/kg. There was a trend toward lower clearances in younger patients. CONCLUSION:This is the first report of individualized pharmacokinetic parameters of ketorolac in children in which the majority of subjects were younger than 6 months old.

Video assessment of supraglottic airway orientation through the perilaryngeal airway in pediatric patients.

The COBRA perilaryngeal airway (PLA) is a new supraglottic airway device available for use in children. We studied the orientation of the larynx as viewed through the PLA using video obtained with a fiberoptic bronchoscope in 45 infants and children. Laryngeal view was scored, and position of the grill bars of the PLA and the epiglottis was assessed. An acceptable airway was obtained in all subjects, but the laryngeal view was nearly or completely obstructed in 76.9% of the patients 10 kg and less, with the epiglottis folded over the glottic opening. This was uncommon in larger children. The grill bars of the PLA were closely opposed to the epiglottis and supraglottic structures in nearly all subjects. We conclude that 1) the PLA provides an acceptable airway in infants and children, but infolding of the epiglottis with obstruction of the view of the glottic opening is common in infants, 2) extra vigilance for airway obstruction in this age group is necessary, and 3) the PLAs close opposition to the supraglottic structures suggests that removal in a deeper plane of anesthesia might minimize laryngeal stimulation.

Positive Intravascular Test Dose Criteria in Children During Total Intravenous Anesthesia with Propofol and Remifentanil Are Different than During Inhaled Anesthesia

BACKGROUND: The use of local anesthetic test doses is standard practice when performing regional anesthesia. When an intravascular test dose is administered during inhaled anesthesia, the heart rate does not increase in about 25% of children; altered T-wave amplitude is a better indicator. No studies have examined the criteria for a positive result during total IV anesthesia (TIVA) in children. METHODS: We studied the effect of a simulated positive test dose on heart rate, arterial blood pressure, and T-wave amplitude in 17 ASA physical status I or II children receiving TIVA with propofol and remifentanil. Bupivacaine 0.25% 0.1 mL/kg with epinephrine 1:200,000 was injected IV, and vital signs and electrocardiogram were continuously monitored. Increases of heart rate and arterial blood pressure >10% and T-wave amplitude >25% of baseline were considered clinically significant changes. RESULTS: All subjects had increased systolic and diastolic blood pressure (30.3% ± 11.7% and 49.3% ± 16.7%), which peaked within 120 s. Heart rate increases >10% of baseline occurred in 73% of subjects. T-wave amplitude increased in 33.3%, was unchanged in 25%, and decreased in 41.7% of subjects. CONCLUSIONS: A positive test dose during TIVA is best detected by increased arterial blood pressure. Twenty-seven percent of intravascular injections were missed using heart rate criteria. T-wave amplitude is not a reliable indicator of intravascular injection during TIVA. This is in marked distinction to what is seen during inhaled anesthesia.

Effectiveness of an Anesthetic Continuous-Infusion Device in Children With Cerebral Palsy Undergoing Orthopaedic Surgery

Background Effective postoperative pain management is a vital component of orthopaedic surgical care in the pediatric population. In children with cognitive impairments pain management can be difficult, making these children vulnerable to ineffectively managed postoperative pain. This prospective, randomised study evaluated the use of a local anesthetic continuous infusion device (pain pump) to manage postoperative pain in children with cerebral palsy (CP) undergoing lower extremity orthopaedic surgical procedures. Methods Children with a diagnosis of CP who were undergoing select orthopaedic outpatient procedures were enrolled in this study. Postoperatively, patients were randomised to receive either a pain pump in addition to oral analgesics or oral analgesics only. Patients parents were asked to record the amount of medication administered and assess pain intensity with the use of a modified visual analogue scale for 3 days postoperatively. Parents also completed an overall pain management satisfaction questionnaire at the end of the study participation period. Results Fifty-four patients were enrolled in this study and data were analyzed on 37 patients. The mean daily pain intensity in the pain pump group was significantly lower for the day of surgery and for 2 days postoperatively, and there was an overall significant difference between the groups (P<0.0001). The amount of analgesic medication administered was significantly lower for the first 2 postoperative days, but there was not a significant difference between the 2 groups overall (P=0.29). Parent satisfaction with both pain management techniques was high and responses were similar between the 2 groups. Conclusions Children with CP present unique postoperative pain management concerns that can be effectively addressed through the use of multimodal analgesic techniques. This study found that the pain pump is an effective pain management technique that significantly reduces pain intensity in children with CP after lower extremity orthopaedic procedures. Level of Evidence Therapeutic Level II.

Long-term use of clonidine in a critically-ill infant

We report the use of clonidine in an infant as an adjunct to sedation and analgesia for 4 months in the critical care setting. Advantages, potential side effects, and dosing for multiple modes of delivery are discussed.

A 15-year review of children with Kawasaki's Syndrome having general anesthesia or deep sedation

Background:  Children with Kawasakis syndrome (KS), also known as Kawasakis disease or ‘mucocutaneous lymph node syndrome’, have approximately 20–25% incidence of developing coronary artery aneurysms (CAA), stenosis or obliteration if not appropriately diagnosed and treated. In addition some children have myocarditis, pericardial effusions and/or cardiac arrhythmias during the acute phase of KS. Even with current treatment protocols, 2–4% will still be at risk of coronary artery pathology and the long‐term implications regarding future coronary artery disease are unknown. Many of these children present for surgical or diagnostic procedures requiring general anesthesia or deep sedation. Only sporadic case reports have been published on the anesthetic experiences of such patients.