William M. Splinter

A Randomized Trial of Tranexamic Acid to Reduce Blood Transfusion for Scoliosis Surgery

Pediatric patients who undergo posterior spinal fusion surgery to correct scoliosis often require multiple blood transfusions. Tranexamic acid is a synthetic antifibrinolytic drug that reduces transfusion requirements in cardiac surgery and total knee arthroplasty. We evaluated the efficacy of prophylactic tranexamic acid to reduce perioperative blood transfusion requirements in a prospective, double-blinded, placebo control study. Forty patients, 9–18 yr of age, were randomized to either tranexamic acid (initial dose of 10 mg/kg and infusion of 1 mg · kg−1 · h−1) or placebo (isotonic saline). Perioperative management was standardized. A uniform transfusion threshold for noncell saved red blood cells was 7.0 g/dL. The total amount of blood transfused in the perioperative period was significantly reduced in the Tranexamic group (P = 0.045). No thrombotic complications were detected in either group. The administration of prophylactic tranexamic acid in patients with scoliosis undergoing posterior spinal fusion surgery has the potential to reduce perioperative blood transfusion requirements.

Dexamethasone decreases vomiting by children after tonsillectomy

We evaluated the effect of dexamethasone on vomiting after elective tonsillectomy in 133 healthy children aged 2-12 yr in a randomized, stratified, blocked, double-blind, placebo-controlled study. General anesthesia was induced by inhalation of N2 O and halothane or intravenously (IV) with propofol. Anesthesia was maintained with N2 O and halothane. Dexamethasone 150 micro g/kg up to a maximum dose of 8 mg, or placebo, was administered IV before surgery. All patients received 1.5 mg/kg codeine intramuscularly (IM) intraoperatively. Perioperative IV fluids, management of emesis, postoperative pain and hospital discharge criteria were all standardized. The groups were similar with respect to number, age, weight, length of surgery, and estimated intraoperative blood loss. Dexamethasone reduced the overall incidence of vomiting from 72% (placebo) to 40% (P < 0.001). Vomiting, both in-hospital and postdischarge, was decreased by the prophylactic administration of dexamethasone. Each episode of inhospital vomiting prolonged discharge by 13 +/- 2 min, mean +/- SD (P < 0.001). In conclusion, dexamethasone markedly decreased vomiting by healthy children after elective tonsillectomy in an ambulatory hospital setting. (Anesth Analg 1996;83:913-6)

Midazolam reduces vomiting after tonsillectomy in children

The purpose of this study was to assess the effect of midazolam on vomiting after tonsillectomy in children. We compared 215 children aged 1.5–14 yr undergoing tonsillectomy or adenotonsillectomy under general anaesthesia with nitrous oxide and halothane. In a double-blind fashion the subjects were administered either placebo or midazolam 75 μg · kg−1 iv after induction of anaesthesia. After the operation, the number of emetic episodes and the length of stay in hospital were recorded. The groups were similar with respect to age, weight, sex, mode of induction, duration of anaesthesia, surgical procedure, opioid administration and length of stay in the PAR and the Day Care Surgical Unit. The 108 midazolam-treated children had a lower incidence (42% vs 57%) of vomiting than the placebo group, P < 0.02. The placebo group had a higher incidence (9% vs 2%) of unscheduled admissions to hospital due to nausea and vomiting, P < 0.05. It is concluded that midazolam administered intravenously to children intraoperatively reduces vomiting after tonsillectomy.RésuméCette étude vise à évaluer chez les enfants l’effet du midazolam sur les vomissements post-amygdalectomie. Nous étudions 215 enfants dont l’âge se situe entre 1,5 et 14 ans soumis à une amygdaleclomie ou à une adéno-amygdalectomie sous anesthésie générale à l’halothane et au protoxyde d’azote. Les sujets reçoivent en double aveugle soit un placebo soit du midazolam 75 μg · kg−1 après l’induction de l’anesthésie. Après l’intervention, le nombre d’épisodes émétiques et la durée du séjour à l’hôpital sont enregistrés. Les groupes sont comparables pour l’âge, le poids, le sexe, le mode d’induction, la durée de l’anesthésie, l’intervention chirurgicale, l’administration de morphinique et la durée du séjour en salle d’opération et à l’unité de chirurgie d’un jour. Les 108 enfants traités au midazolam vomissent moins (42% vs 57%) que le groupe placebo. L’incidence des admissions imprévues à l’hôpital pour nausées est vomissements est plus élevée dans le groupe placebo (9% vs 2%, P < 0,05). Nous concluons que l’administration iv de midazolam pendant l’intervention diminue l’incidence des nausées et des vomissements après l’amygdalectomie.

Low-dose Ondansetron with Dexamethasone More Effectively Decreases Vomiting after Strabismus Surgery in Children than Does High-dose Ondansetron

Background Ondansetron and dexamethasone have been observed to decrease the incidence of vomiting by children after general anesthesia. This study compared the effect of high‐dose (150 micro gram/kg) ondansetron with low‐dose (50 micro gram/kg) ondansetron plus 150 micro gram/kg dexamethasone on the incidence of vomiting after strabismus in children. Methods This study had a double‐blind, blocked, stratified, randomized design. With parental consent and Hospital Ethics Committee approval, healthy children aged 2–14 yr who were undergoing elective strabismus surgery were studied. Anesthesia was induced intravenously with propofol or by inhalation with halothane and nitrous oxide. Patients in the high‐dose group were given placebo plus 150 micro gram/kg (maximum dose, 8 mg) of ondansetron intravenously, whereas patients in the low‐dose group were given 150 micro gram/kg dexamethasone (maximum dose, 8 mg) and 50 micro gram/kg ondansetron intravenously in a double‐blind manner. Anesthesia was maintained with halothane and nitrous oxide. All incidences of vomiting occurring as long as 24 h after anesthesia were recorded. Results Three of the 200 patients enrolled in the study were excluded from data analysis. The groups were similar with respect to demographic data and potential confounding variables. Patients vomited from 0–12 times. The low‐dose ondansetron plus dexamethasone group had a lower incidence of vomiting, 9% (95% CI = 4–17%) versus 28% (95% CI = 20–38%; P < 0.001). Only 1% of the patients in the low‐dose ondansetron plus dexamethasone group vomited while in the hospital. Conclusions Low‐dose ondansetron plus dexamethasone is an effective prophylactic antiemetic combination for children undergoing strabismus surgery.

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 childrens 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 childrens 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.)

Preoperative fasting in children.

Children undergo a preoperative fast in an attempt to minimize the fluid and solid food component of gastric contents. The importance of a preoperative fast was acknowledged early in the evolution of anesthesia as a discipline of medicine. In response to concerns about the aspiration of gastric contents, a prolonged fast presumably came into vogue. With this practice, it was not unusual to have hungry, irritable children who were prone to hypoglycemia after fasts of 8 ‐12 h or even longer. The purpose of this article is to provide the reader with a narrative review of the literature pertaining to preoperative fasting in children. This article is primarily focused on randomized controlled trials (RCTs), but when not available, literature of lesser intensity was used. We present the physiology of gastric emptying with an emphasis on studies focusing on children in the perioperative period. These studies of gastric emptying were, when possible, divided into studies involving solid food and those involving clear fluids. We then present preoperative fasting of children, which was subdivided by age (neonates, infants, toddlers, and adolescents) and by health (elective versus emergent surgery and healthy versus medically compromised patients). In the concluding portions of this review, we present recommendations for the management of perioperative fasting and recommendations with respect to the need for more research, as more questions remain unanswered than those that have been answered. During preparation of this article, we accepted several links. The linkage between gastric fluid volume and aspiration pneumonia for healthy patients has recently been examined by an ASA taskforce, which concluded that the available data were insufficient to confirm or deny a relationship. Although this means that gastric fluid volume is a surrogate end point for aspiration pneumonia, virtually all studies examining preoperative feeding practices have gastric residual volume as their primary end point. For the purpose of this review, we focus on the end point of gastric residual volume, which is the almost exclusive choice of numerous peer-reviewed investigations. Furthermore, in the practice of anesthesia, patients undergoing emergency surgery have increased gastric contents and are at increased risk of aspiration pneumonia. This is an established link, and if we were to refute it, we would deny the need for rapid-sequence induction plus appropriate airway management during general anesthesia for emergency surgery. Although increased gastric contents increase the risk of aspiration pneumonia, there is no known gastric fluid volume that places a particular patient at clinically relevant risk or eliminates all risk.

Prophylaxis for vomiting by children after tonsillectomy: dexamethasone versus perphenazine.

The effects of dexamethasone and perphenazine on vomiting after tonsillectomy in children were compared in 226 healthy children aged 2-12 yr. The study was randomized, stratified, blocked, and double-blind. Anesthesia was induced intravenously (IV) with propofol or by inhalation with halothane and N2 O. Dexamethasone 150 micro g/kg or perphenazine 70 micro g/kg was administered IV after the induction of anesthesia in a double-blind fashion. Perioperative management of emesis, pain, fluids, and patient discharge was all standardized. The groups had similar demographic characteristics. Perphenazine significantly reduced the incidence of in-hospital vomiting compared with dexamethasone (13% vs 36%, P < 0.001). The incidence of out-of-hospital vomiting was almost identical. Overall, the incidence was significantly different for perphenazine vs dexamethasone (33% vs 46%, P = 0.04) using logistic regression analysis. Of note, sex and induction technique were significant predictors of postoperative vomiting (P < 0.05) using logistic regression analysis, with male patients and those patients undergoing IV induction vomiting less. In conclusion, perphenazine more effectively decreases vomiting by children after tonsillectomy in an ambulatory hospital setting compared with dexamethasone. Implications: Postoperative vomiting can have many debilitating effects, and children undergoing tonsillectomy are at particular risk. We compared the effects of dexamethasone and perphenazine on vomiting after tonsillectomy in 266 children. We found perphenazine more effective than dexamethasone before discharge from hospital but that the two drugs have similar effects after discharge. (Anesth Analg 1997;85:534-7)

Reducing pain after inguinal hernia repair in children: caudal anesthesia versus ketorolac tromethamine.

Background The optimal method to achieve analgesia after inguinal hernia repair in children is unknown. This study compared the analgesic efficacy, adverse events, and the costs associated with supplementation of local anesthesia (infiltration of the wound) with either intravenous ketorolac or caudal analgesia in children having inguinal hernia repair. Methods With parental consent and institutional review board approval, children aged 2-6 yr having elective, outpatient inguinal hernia repair were studied in this randomized, single-blinded investigation. Anesthesia was induced by inhalation with nitrous oxide and halothane or intravenously with propofol. Anesthesia was maintained with nitrous oxide and halothane. Patients were randomly assigned to receive caudal analgesia (1 ml/kg 0.20% bupivacaine with 1/200,000 epinephrine) or intravenous ketorolac (1 mg/kg) immediately after induction of anesthesia. Both groups received field blocks with 0.25% bupivacaine administered by the surgeon under direct vision during operation. Patients were assessed for 24 h. In-hospital pain was assessed using a behavior-based pain score. Parents assessed pain with a visual linear analog pain scale with anchors of 0 (no pain) and 100 (worst pain imaginable). Results The authors studied 164 children, with 84 patients in the ketorolac group. The groups had similar demographic data. In-hospital analgesic requirements and pain scores were almost identical in both groups. Pain at home was significantly less in the ketorolac group, with visual linear analog pain scale scores of 10 (0-80) compared with 20 (0-80) (median [range]) for ketorolac versus caudal (P = 0.002 by the Mann-Whitney U test). The ketorolac group also had a lower incidence of vomiting, ambulated more rapidly, and micturated earlier (P < 0.05). Conclusion The use of intravenous ketorolac to supplement local anesthesia infiltrated by the surgeon during pediatric inguinal hernia repair is superior to supplementation with caudal analgesia.

Removal of the laryngeal mask airway in children: Deep anesthesia versus awake

STUDY OBJECTIVE To compare the incidence of adverse airway events identified with removal of the laryngeal mask airway (LMA) from an awake child or from a child before his or her airway reflexes had returned. DESIGN Prospective, randomized study. SETTING University-affiliated childrens hospital. PATIENTS 333 ASA physical status I and II patients ages 1.5 to 15 years undergoing elective surgery. INTERVENTIONS At the time of removal of the LMA at the end of surgery, patients were anesthetized or had intact airway reflexes. MEASUREMENTS AND MAIN RESULTS Any airway problems occurring within 15 minutes of LMA removal were recorded. These problems included airway obstruction (laryngeal spasm and biting of the LMA), peripheral hemoglobin oxygen saturation less than 90%, stridor requiring manipulation of the airway, vomiting, retching, and excessive salivation. Airway problems occurred after LMA removal among 23 children who had their LMA removed prior to return of airway reflexes, and among 13 subjects who had their LMA removed after the return of airway reflexes. CONCLUSION Removal of the LMA during anesthesia and after return of airway reflexes results in a similar incidence of airway problems in children.

In children, nitrous oxide decreases pain on injection of propofol mixed with lidocaine

PurposeTo investigate if 50% nitrous oxide reduces the pain during injection of propofol mixed with lidocaine in children.MethodsHealthy children undergoingiv induction of general anesthesia for elective surgery were recruited into this prospective, randomized, double-blind study. None of the patients received any premedication except for eutectic mixture of local anesthetics cream. Before induction of anesthesia with propofol 1% mixed with lidocaine 0.05% (propofol dose 3 mg·kg−1), the treatment group received 50% N2O in O2 and the control group received 100% oxygen. Pain due to propofol administration was rated with a four-point behavioural scale: none, mild, moderate or severe.ResultsThere were 28 subjects in the control group and 26 subjects in the treatment group. Demographic data were similar in both groups. The incidence of pain at induction was 4% after N2O and 36% in the control group,P < 0.01. No patients had severe pain. Most patients had mild pain. Three of the ten patients with pain in the control group had moderate pain. The number needed to treat was 3:1.ConclusionNitrous oxide reduces pain during induction with propofol mixed with lidocaine in healthy children.RésuméObjectifVérifier si du protoxyde d’azote à 50 % peut réduire la douleur de l’injection d’un mélange de propofol et de lidocaïne chez des enfants.MéthodeDes enfants en bonne santé devant subir l’induction intraveineuse d’une anesthésie générale, pour une intervention non urgente, ont participé à une étude prospective, randomisée et à double insu. Aucun enfant n’a reçu de prémédication, sauf un mélange eutectique de crème anesthésique locale. Avant l’induction de l’anesthésie avec un mélange de propofol à 1 % et de lidocaïne à 0,05 % (3 mg·kg−1 de propofol), les enfants du groupe expérimental ont reçu un mélange de N2O et de O2à 50 % et les enfants témoins, 100 % d’oxygène. La douleur causée par l’administration de propofol a été cotée selon une échelle en quatre points : aucune douleur, douleur légère, modérée ou sévère.RésultatsLe groupe témoin comprenait 28 sujets et le groupe expérimental, 26. Les données démographiques étaient comparables entre les groupes. L’incidence de douleur à l’induction a été de 4 % après l’administration de N2O et de 36 % chez les témoins, P < 0,01. Aucun patient n’a éprouvé de douleur sévère. La plupart n’ont subi que de légères douleurs. Trois des dix patients qui ont présenté des douleurs dans le groupe témoin ont eu des douleurs modérées. Le nombre nécessaire pour traiter a été de 3:1.ConclusionLe protoxyde d’azote réduit la douleur pendant l’induction de l’anesthésie avec un mélange de propofol et de lidocaïne chez des enfants en bonne santé.