Susan T. Verghese

International evidence-based recommendations on ultrasound-guided vascular access

PurposeTo provide clinicians with an evidence-based overview of all topics related to ultrasound vascular access.MethodsAn international evidence-based consensus provided definitions and recommendations. Medical literature on ultrasound vascular access was reviewed from January 1985 to October 2010. The GRADE and the GRADE-RAND methods were utilised to develop recommendations.ResultsThe recommendations following the conference suggest the advantage of 2D vascular screening prior to cannulation and that real-time ultrasound needle guidance with an in-plane/long-axis technique optimises the probability of needle placement. Ultrasound guidance can be used not only for central venous cannulation but also in peripheral and arterial cannulation. Ultrasound can be used in order to check for immediate and life-threatening complications as well as the catheter’s tip position. Educational courses and training are required to achieve competence and minimal skills when cannulation is performed with ultrasound guidance. A recommendation to create an ultrasound curriculum on vascular access is proposed. This technique allows the reduction of infectious and mechanical complications.ConclusionsThese definitions and recommendations based on a critical evidence review and expert consensus are proposed to assist clinicians in ultrasound-guided vascular access and as a reference for future clinical research.

Comparison of three techniques for internal jugular vein cannulation in infants

Central venous cannulation allows accurate monitoring of right atrial pressure and infusion of drugs during the anaesthetic management of infants undergoing cardiopulmonary bypass. In this prospective, randomized study, we compared the success and speed of cannulation of the internal jugular vein in 45 infants weighing less than 10 kg using three modes of identification: auditory signals from internal ultrasound (SmartNeedle, SM), external ultrasound imaging (Imaging Method, IM) and the traditional palpation of the carotid pulsation and other landmarks (Landmarks Method, LM). The cannulation time, number of attempts with LM and SM techniques were greater than those with IM technique. The incidence of carotid artery puncture and the success rate were not significantly different among the three groups. In infants, a method based on visual ultrasound identification (IM) of the internal jugular vein is more precise and efficient than methods based on auditory (SM) and tactile perception (LM).

Acute pain management in children

The greatest advance in pediatric pain medicine is the recognition that untreated pain is a significant cause of morbidity and even mortality after surgical trauma. Accurate assessment of pain in different age groups and the effective treatment of postoperative pain is constantly being refined; with newer drugs being used alone or in combination with other drugs continues to be explored. Several advances in developmental neurobiology and pharmacology, knowledge of new analgesics and newer applications of old analgesics in the last two decades have helped the pediatric anesthesiologist in managing pain in children more efficiently. The latter include administering opioids via the skin and nasal mucosa and their addition into the neuraxial local anesthetics. Systemic opioids, nonsteroidal anti-inflammatory agents and regional analgesics alone or combined with additives are currently used to provide effective postoperative analgesia. These modalities are best utilized when combined as a multimodal approach to treat acute pain in the perioperative setting. The development of receptor specific drugs that can produce pain relief without the untoward side effects of respiratory depression will hasten the recovery and discharge of children after surgery. This review focuses on the overview of acute pain management in children, with an emphasis on pharmacological and regional anesthesia in achieving this goal.

The effects of the simulated Valsalva maneuver, liver compression, and/or Trendelenburg position on the cross-sectional area of the internal jugular vein in infants and young children

UNLABELLED We calculated the effects of the simulated Valsalva (V), liver (L) compression, and Trendelenburg (T) position on the cross-sectional area (CSA) of the right internal jugular vein by using planimetry (Aloka ultrasound machine) in 84 infants and young children. Eight combinations of positions and interventions were studied for each patient, with the patient supine, in the T position, during the simulated V maneuver, with L compression and a combination of maneuvers. Data were analyzed by using Friedmans chi(2) test and Wilcoxons signed rank test. An increase of >25% in the CSA of the internal jugular vein was considered significant. In infants, the maximal mean increase achieved with the combination of all 3 maneuvers was only 17.4% +/- 16.1%. As a single maneuver, the simulated V was the most effective (11.6% +/- 11.5%). In children, the combination of all 3 maneuvers performed simultaneously produced a mean 65.9% (SD +/- 44.7%) increase in the CSA, which was larger than the increase by all other maneuvers alone or in a single combination (Friedmans test, P < 0.001 and Wilcoxons test, P < 0.002). As a single maneuver, V produced the most increase (40.4% +/- 32.2%) compared with L compression (14.3% +/- 18.9%) or T position (24.3% +/- 27.1%). IMPLICATIONS The combinations of simulated Valsalva, liver compression, and Trendelenburg maneuvers produce the maximal mean increase in the size of the internal jugular vein in infants and young children, with the Valsalva maneuver being the most effective single maneuver. This increase is significant in young children, but negligible in infants.

A randomized controlled trial to evaluate S-Caine patch for reducing pain associated with vascular access in children.

Background:A randomized, double-blinded trial was performed to evaluate the efficacy and safety of the S-Caine Patch™ (ZARS, Inc., Salt Lake City, UT), a eutectic mixture of lidocaine and tetracaine, for pain relief during venipuncture in children. Methods:With institutional review board approval, parental consent, and patient assent, 64 children who were scheduled for medically indicated vascular access at two centers were randomly assigned (2:1) to receive either an S-Caine Patch™ or a placebo patch for 20 min before venipuncture procedures. The primary outcome measure was the child’s rating of pain during venipuncture using the Oucher pain scale. Additional measures of efficacy included the blinded investigator’s and an independent observer’s four-point categorical scores. Variables were compared between treatments using Mantel–Haenszel summary chi-square tests or Pearson chi-square tests. Results:The S-Caine Patch™ produced significantly greater pain relief compared with placebo (median Oucher scores of 0 vs. 60; P < 0.001). Fifty-nine percent of the children in the S-Caine Patch™ group reported no pain compared with 20% of the children in the placebo patch group. The investigator estimated that 76% of the children in the S-Caine Patch™ group experienced no pain during venipuncture versus 20% in the placebo patch group (P = 0.001). Independent observer ratings also favored the S-Caine Patch™ (P < 0.001). Mild skin erythema (< 38%) and edema (< 2%) occurred with similar frequencies between the groups. Conclusion:This study demonstrated that a 20-min application of the S-Caine Patch™ is effective in lessening pain associated with venipuncture procedures. Adverse events after S-Caine Patch™ application were mild and transient.

Emergence airway complications in children: a comparison of tracheal extubation in awake and deeply anesthetized patients.

We compared the differences in oxygen saturation and airway-related complications after tracheal extubation in pediatric patients undergoing elective strabismus surgery or adenoidectomy and/or tonsillectomy who were awake versus anesthetized. Seventy otherwise healthy patients between 2 and 8 yr of age were studied. Anesthesia was induced with halothane or thiamylal and maintained with nitrous oxide and halothane. After induction of anesthesia, the patients were randomly assigned to group 1 (awake extubation) or group 2 (anesthetized extubation). Oxygen saturation was measured continuously and recorded 10 min before extubation and at 1, 2, 3, 5, 7, 10, 15, 20, 25, and 30 min after tracheal extubation. Supplemental oxygen was administered when oxygen saturation values were less than 90% while breathing room air. Oxygen saturation levels were higher in group 2 than in group 1 at 1, 2, 3, and 5 min after extubation. There were no differences between the two groups in the number of patients requiring supplemental oxygen. The incidence of airway-related complications such as laryngospasm, croup, sore throat, excessive coughing, and arrhythmias was not different between the two groups. We conclude that the anesthesiologists preference or surgical requirements may dictate the choice of extubation technique in otherwise healthy children undergoing elective surgery.

Fast-tracking children after ambulatory surgery.

This study was designed to determine the feasibility and benefits of fast-tracking children after ambulatory surgery. One-hundred-fifty-five healthy children undergoing surgical procedures lasting <90 min were studied in a randomized manner. After surgery, children who met predefined recovery criteria in the operating room were entered into one of the study groups. Seventy-one patients (control) were first admitted to the postanesthesia care unit (PACU) and then to the second-stage recovery unit (SSRU). Eighty-four children bypassed the PACU and were directly admitted to the SSRU (Fast-Track group). The demographic data, airway management, and surgical procedures were similar in both groups of patients. During the recovery phase, 62.0% of the PACU group patients and 40.5% of the Fast-Track patients received analgesics (P = 0.01). The total recovery time was 79.1 ± 48.3 min in the Fast-Track group and 99.4 ± 48.6 min in the Control group (P = 0.008). A larger percentage of parents in the Fast-Track group (31% vs 16%) reported that their child was restless on arrival at the SSRU (P = 0.037). There were no clinically significant adverse events. However, adequate pain control must be provided before transfer to SSRU. In conclusion, fast-tracking children after ambulatory surgery is feasible and beneficial when specific selection criteria are used.

The Effect of Intranasal Administration of Remifentanil on Intubating Conditions and Airway Response After Sevoflurane Induction of Anesthesia in Children

BACKGROUND: Intubation without the use of muscle relaxants in children is frequently done before IV access is secured. In this randomized controlled trial, we compared intubating conditions and airway response to intubation (coughing and/or movement) after sevoflurane induction in children at 2 and 3 min after the administration of intranasal remifentanil (4 mcg/kg) or saline. METHODS: One hundred eighty-eight children, 1–7-yr old, were studied. Nasal remifentanil (4 mcg/kg) or saline was administered 1 min after an 8% sevoflurane N2O induction. The sevoflurane concentration was then reduced to 5% in oxygen, and ventilation assisted/controlled. An anesthesiologist blinded to treatment assignment used a validated score to evaluate the conditions for laryngoscopy and response to intubation. Blood samples for determination of remifentanil blood concentrations were collected from 17 children at baseline, 2, 3, 4, and 10 min after nasal administration of remifentanil. RESULTS: Good or excellent intubating conditions were achieved at 2 min (after the remifentanil bolus) in 68.2% and at 3 min in 91.7% of the children who received intranasal remifentanil versus 37% and 23% in children who received placebo (P < 0.01). The mean remifentanil plasma concentrations (±sd) at 2, 3, 4, and 10 min were 1.0 (0.60), 1.47 (0.52), 1.70 (0.46), and 1.16 (0.36) ng/mL, respectively. Peak plasma concentration was observed at 3.47 min. There were no complications associated with the use of nasal remifentanil. CONCLUSIONS: Nasal administration of remifentanil produces good-to-excellent intubating conditions in 2–3 min after sevoflurane induction of anesthesia.

Pharmacokinetics and pharmacodynamics of fenoldopam mesylate for blood pressure control in pediatric patients

BackgroundFenoldopam mesylate, a selective dopamine1-receptor agonist, is used by intravenous infusion to treat hypertension in adults. Fenoldopam is not approved by the FDA for use in children; reports describing its use in pediatrics are limited. In a multi-institutional, placebo controlled, double-blind, multi-dose trial we determined the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics and side-effect profile of fenoldopam in children.MethodsSeventy seven (77) children from 3 weeks to 12 years of age scheduled for surgery in which deliberate hypotension would be induced were enrolled. Patients were randomly assigned to one of five, blinded treatment groups (placebo or fenoldopam 0.05, 0.2, 0.8, or 3.2 mcg/kg/min iv) for a 30-minute interval after stabilization of anesthesia and placement of vascular catheters. Following the 30-minute blinded interval, investigators adjusted the fenoldopam dose to achieve a target mean arterial pressure in the open-label period until deliberate hypotension was no longer indicated (e.g., muscle-layer closure). Mean arterial pressure and heart rate were continuously monitored and were the primary endpoints.ResultsSeventy-six children completed the trial. Fenoldopam at doses of 0.8 and 3.2 mcg/kg/min significantly reduced blood pressure (p < 0.05) during the blinded interval, and doses of 1.0–1.2 mcg/kg/min resulted in continued control of blood pressure during the open-label interval. Doses greater than 1.2 mcg/kg/min during the open-label period resulted in increasing heart rate without additional reduction in blood pressure. Fenoldopam was well-tolerated; side effects occurred in a minority of patients. The PK/PD relationship of fenoldopam in children was determined.ConclusionFenoldopam is a rapid-acting, effective agent for intravenous control of blood pressure in children. The effective dose range is significantly higher in children undergoing anesthesia and surgery (0.8–1.2 mcg/kg/min) than as labeled for adults (0.05–0.3 mcg/kg/min). The PK and side-effect profiles for children and adults are similar.

Caudal Anesthesia in Children: Effect of Volume Versus Concentration of Bupivacaine on Blocking Spermatic Cord Traction Response During Orchidopexy

In this study we compared the intensity and level of caudal blockade when two different volumes and concentrations of a fixed dose of bupivacaine were used. Fifty children, 1–6 yr old, undergoing unilateral orchidopexy received a caudal block with a fixed 2 mg/kg dose of bupivacaine immediately after the induction. Group 1 (n = 23) received 0.8 mL/kg of 0.25% bupivacaine, whereas Group 2 (n = 27) received 1.0 mL/kg of 0.2% bupivacaine. Epinephrine 1:400,000 and 0.1 mL of sodium bicarbonate per 10 mL of local anesthetic solution were added. There were no statistically significant differences between the two groups in their anesthesia, surgery, recovery, and discharge times. Fifteen patients (65.2%) in Group 1 required an increase in inspired halothane concentration to block hemodynamic and/or ventilatory response during spermatic cord traction, as compared with 8 patients (29.6%) in Group 2 (P = 0.022). In the recovery room, four (17.4%) patients in Group 1 required rescue treatment with fentanyl, versus two (7.4%) in Group 2 (P = 0.372). In children undergoing orchidopexy, a caudal block with a larger volume of dilute bupivacaine is more effective than a smaller volume of the standard 0.25% solution in blocking the peritoneal response during spermatic cord traction, with no change in the quality of postoperative analgesia.