Effect of anesthesia for hypospadias repair on perioperative complications.

BACKGROUND: Recent publications from the United States, India, and Korea report that children undergoing hypospadias repair with caudal regional anesthesia/analgesia could have increased postoperative surgical complications. AIMS: The purpose of this retrospective cohort study was to assess the impact between caudal regional anesthesia, other regional anesthesia, and no regional anesthesia on complications after hypospadias repair at a tertiary care children's hospital in Ottawa, Canada, with an expectation to changing practices if a link was found. METHOD: We reviewed the health records of 827 children with hypospadias undergoing penile surgery from January 1991-June 2017. The final sample size for the analysis consisted of 764 patients and 825 procedures. RESULTS: The overall complications were almost identical when considering anesthesia effects, and this similarity persisted when we assessed specifically for only surgical complications. We had 716, 94, and 15 subjects who had a caudal block, penile block, and general anesthesia only, respectively, and their complication rates were 28, 31, and 27%, respectively, and their fistula formation rates were 10, 6, and 0%, respectively, and their stricture formation rates were 8, 7, and 20%,, respectively. Hypospadias type and surgical repair technique were marked predictors of complications in the postoperative period. CONCLUSION: Anesthesia technique appears to have minor impact on complications after hypospadias repair, while surgical technique and type of hypospadias impact complications after hypospadias surgery in children. Based upon these results, we will not change our current practice of using a variety of regional anesthesia techniques for children undergoing hypospadias repair.

The impact of pneumoperitoneum and Trendelenburg positioning on respiratory system mechanics during laparoscopic pelvic surgery in children: a prospective observational study.

PURPOSE: The aim of this study was to describe the changes in respiratory system compliance and other measures of respiratory mechanics associated with peritoneal insufflation (12 mmHg pressure) with carbon dioxide (PNP12) and 20° Trendelenburg positioning (TDG20) in pediatric patients undergoing laparoscopic surgery for abdominal cryptorchidism. METHODS: Twelve subjects with abdominal cryptorchidism undergoing orchiopexy were enrolled in the study. General anesthesia was conducted with sevoflurane/O2/air, fentanyl, and rocuronium. Pressure-controlled ventilation with a peak inspiratory pressure (PIP) of 10-15 cm H2O and a positive end-expiratory pressure of 5 cm H2O was titrated to achieve a tidal volume (VT/kg) of 6-10 mL·kg(-1) and end-tidal carbon dioxide (EtCO2) of 35-40 mmHg. Adjustments of PIP and respiratory rate (RR) were made to maintain the initial VT/kg and EtCO2 < 50 mmHg. Measurements of weight-corrected dynamic compliance (Cdyn/kg), VT/kg, and EtCO2 were recorded at baseline, after PNP12, at TDG20, and again after deflation and return to the level position. RESULTS: Adjustments in PIP were required in all subjects to maintain the target VT/kg. The Cdyn/kg decreased 42% (95% confidence interval [CI]: 30 to 51; P < 0.001) after PNP12, and it remained below baseline until deflation. The TDG20 caused only minimal additional reductions in Cdyn/kg (10% decrease; 95% CI: 0 to 19; P = 0.048). The VT/kg decreased 42% (95% CI: 31 to 52; P = 0.048) with PNP12, and after TDG20, it decreased a further 10% (95% CI: 4 to 19; P = 0.038). After deflation, the VT/kg increased by 56% (95% CI: 28 to 90; P = 0.001) and was then adjusted back to the initial values. CONCLUSION: The PNP12 significantly decreases Cdyn/kg and VT/kg in pediatric patients. The use of TDG20 produces a relatively minor additional impact in respiratory mechanics. This study emphasizes the need to adjust ventilator settings to maintain normal gas exchange during this procedure.

Somatic paravertebral block decreases opioid requirements in children undergoing appendectomy.

PURPOSE: Somatic paravertebral block (SPVB) appears to provide effective and prolonged nerve block in children; however, study of its use in this population is limited. We compared SPVB with no block in children undergoing appendectomy. METHODS: Thirty-six children aged 3-16 yr undergoing open appendectomy were involved in this prospective randomized controlled study. Anesthesia was induced with propofol and maintained with isoflurane in N(2)O/oxygen. All subjects received fentanyl, acetaminophen and ketorolac during anesthesia. Group I (SPVB) subjects received a right SPVB at T(11), T(12), and L(1) using 0.2% ropivacaine 0.25 mL.kg(-1) with epinephrine 1:200,000 preoperatively. Group II (Control) had only bandaids applied to skin. Both groups were given morphine 0.05 mg.kg(-1) iv every 2 hr if pain scores reached 5/10 on a visual analogue scale. Acetaminophen was administered postoperatively every 6 hr to both groups. Time to first dose of morphine, total dose of morphine in 24 hr, and any adverse effects up to 24 hr after surgery were recorded. RESULTS: Group I (SPVB) subjects required significantly less morphine than Group II (Control) patients (0.12 +/- 0.07 vs 0.34 +/- 0.15 mg.kg(-1), respectively; P < 0.001), and time to their first dose was significantly longer (7.1 +/- 4.4 vs 2.5 +/- 1.6 hr, respectively; P < 0.001). Incidence of vomiting was 11% with Group I and 27% with Group II (P = 0.21). No other adverse effects were observed in either group. CONCLUSIONS: In children undergoing appendectomy, SPVB provides better pain relief than no block and reduces opioid requirements. Side effects were not statistically different between groups.

The effect of vapocoolant spray on pain due to intravenous cannulation in children: a randomized controlled trial.

BACKGROUND: Established noninvasive pharmacologic means of alleviating pain and anxiety in children undergoing intravenous cannulation are time-consuming, and thus impractical for routine use in the emergency department. Vapocoolant sprays provide transient skin anesthesia within seconds of application. We compared the effect of a new vapocoolant spray to placebo on pain due to intravenous cannulation in children. METHODS: In this double-blind randomized controlled trial, which we conducted between June 1 and Sept. 12, 2006, 80 children aged 6-12 years received either vapocoolant spray or placebo before cannulation. Children rated their pain using a 100-mm colour visual analogue scale. Secondary outcomes included success rate on first attempt at cannulation and pain ratings by the children's parents, nurses and child life specialists. RESULTS: We found a modest but significant reduction in pain with the use of vapocoolant spray (mean difference 19 mm, 95% confidence interval [CI] 6-32 mm; p < 0.01). Cannulation on first attempt was more often successful with the use of vapocoolant spray (85.0%) than with placebo (62.5%) (mean difference 22.5%, 95% CI 3.2%-39.9%; p = 0.03). The number needed to treat to prevent 1 cannulation failure was 5 (95% CI 3-32). Parents (p = 0.04), nurses (p = 0.01) and child life specialists (p < 0.01) considered the children's pain to be reduced with the use of vapocoolant spray. INTERPRETATION: The vapocoolant spray in our study quickly and effectively reduced pain due to intravenous cannulation in children and improved the success rate of cannulation. It is an important option to reduce childhood procedural pain in emergency situations, especially when time precludes traditional interventions. (http://ClinicalTrials.gov trial register no. NCT00130650.).

Addition of morphine to local anesthetic infiltration does not improve analgesia after pediatric dental extractions.

BACKGROUND: Opioid receptors have been noted in the peripheral nerve endings of afferent neurons. Blockade of these receptors with peripherally administered opioids is believed to result in analgesia. METHODS: In a prospective, randomized, double-blind study, we studied the analgesic effects of adding a subsystemic dose of morphine to local anesthetic infiltration (lidocaine hydrochloride) during pediatric dental extractions. Forty-two subjects, aged 2-7 years of ASA physical status I-II, were randomized to receive submucous infiltration with either morphine 25 microg.kg(-1) in 2% lidocaine hydrochloride with 1 : 1 00 000 epinephrine (morphine group) or 2% lidocaine hydrochloride with 1 : 1 00 000 epinephrine (control group) at the end of surgery. RESULTS: There was no difference in postoperative analgesic requirements within the first 24 h. In-hospital acetaminophen consumption was 85% in the morphine group compared with 81% in the control group. CONCLUSION: We conclude that there is no benefit of adding a subsystemic analgesic dose of morphine to local anesthetics for analgesia after dental extractions in children.

Remifentanil decreases sevoflurane requirements in children.

PURPOSE: To establish the effect of increasing concentrations of remifentanil on sevoflurane requirements in children. METHODS: Fifty-eight healthy patients, ASA status I-II aged two to 12 yr, undergoing abdominal wall hernia or hydrocele repairs were serially assigned to one of four test groups to receive remifentanil 0.03 microg.kg(-1).min(-1), 0.06 microg.kg(-1).min(-1), 0.12 microg.kg(-1).min(-1), or 0.25 microg.kg(-1).min(-1) iv. Patients received a bolus of remifentanil 1 microg.kg(-1) iv before the infusion began. End-tidal sevoflurane concentration was adjusted according to a Dixon up-and-down approach. Ten minutes after starting the remifentanil infusion, the surgical incision was made. The patient was observed for one minute from the time of incision by a solitary blinded rater for either flexion or withdrawal of one or more extremities in response to skin incision. RESULTS: The mean minimum alveolar concentration of sevoflurane was 2.39 +/- 0.58 with 0.03 microg.kg(-1).min(-1) remifentanil, 1.91 +/- 0.36 with 0.06 microg.kg(-1).min(-1) remifentanil, and 0.92 +/- 0.11 with 0.12 microg.kg(-1).min(-1) remifentanil. Remifentanil 0.25 microg.kg(-1).min(-1) lead to the sevoflurane being decreased to a level associated with spontaneous patient awakening. The effective dose (ED(50)) values of sevoflurane were 2.44 [95% confidence interval (CI) 2.16-2.72], 2.00 (95% CI 1.78-2.22), and 1.18 (95% CI 0.99-1.36) for remifentanil infusion rates of 0.03 microg.kg(-1).min(-1), 0.06 microg.kg(-1).min(-1), and 0.12 microg.kg(-1).min(-1) respectively. CONCLUSION: The administration of remifentanil produced a dose-dependent decrease in the minimum alveolar concentration of sevoflurane necessary for inhibition of movement reaction in response to surgical incision. The use of remifentanil may allow for flexible analgesic control and rapid recovery in children anesthetized with sevoflurane.

The bispectral index does not correlate with clinical signs of inhalational anesthesia during sevoflurane induction and arousal in children.

PURPOSE: Validation of the bispectral index (BIS) in children requires correlating BIS with several levels of sedation, hypnosis and anesthesia. Our purpose was to compare BIS values with objective assessments of the level of hypnosis in children. We postulated that BIS predicted the level of anesthesia during induction and emergence in children. METHODS: In a prospective observational study, we evaluated the BIS monitor in 87 children (ages: 0.3 to 14 yr) ASA physical status I-II undergoing general surgery under sevoflurane and nitrous oxide. Clinical signs of inhalational anesthesia (CSA), the motor response to surgical incision and signs of arousal were used as indicators of the depth of anesthesia. CSA and BIS measurements were paired every minute during induction and emergence until arousal. RESULTS: CSA scores decreased during induction and increased during emergence (P < 0.001) and correlated with changes in sevoflurane concentrations (r = -0.46; P < 0.001). BIS was associated with changes in CSA scores during induction (r = 0.49; P < 0.01) and emergence (r = 0.62; P < 0.01), but the ranges of individual BIS values overlapped several levels of hypnosis. A BIS value greater than 50 had a positive predictive value of 25% for distinguishing between responders and non-responders to surgical incision. A BIS score equal or greater than 72 had a predictive value of 63% for discriminating between pre-arousal and arousal. CONCLUSIONS: BIS correlates with several levels of hypnosis during inhalational induction and emergence in children, but individual BIS values show large inter-individual variability. The BIS monitor identified the physiological changes associated with arousal and distinguished the effects of preoperative sedation during emergence. The use of movement as an endpoint of hypnosis during surgical stimulation does not correlate with BIS values in children. The large inter-individual variability of BIS at different levels of anesthetic depth may limit the applicability of BIS to pediatric anesthesia.

'Needle-free' delivery of local anesthesia: a valuable option in pediatrics.

Needleless injection or jet injection of medication has had a rather limited clinical use in children's healthcare beyond mass vaccinations. Medications injected into children with a needle-free system include local anesthetic agents, sedatives (midazolam), and anesthetic induction agents (ketamine). Reports suggest that local discomfort is often negligible and costs are often minimal. Risks associated with this simple and flexible technique are considered to be markedly less than alternative approaches, such as syringe and needle. Further investigations are needed to confirm initial reports and establish current and other uses of jet injectors in children.