Paul A. Tripi

The Effect of ε-Aminocaproic Acid on Perioperative Blood Loss in Patients With Idiopathic Scoliosis Undergoing Posterior Spinal Fusion : A Preliminary Prospective Study

Study Design. A prospective study evaluating the efficacy of &egr;-aminocaproic acid (EACA) in decreasing perioperative blood loss in idiopathic scoliosis. Objectives. To compare the perioperative blood loss and need for blood replacement in two groups of patients undergoing surgery for idiopathic scoliosis. One group received intraoperative EACA; the other did not and served as controls. Summary of Background Data. Excessive blood loss increases the operative time, risk for blood product disease transmission, postoperative complications, and costs associated with posterior spinal fusion and instrumentation. EACA is an antifibrinolytic agent that has been shown to be effective in reducing perioperative blood loss during pediatric cardiothoracic surgical procedures. We hypothesized that it would also be effective in lowering blood loss during posterior spinal fusion for idiopathic scoliosis. Methods. We compared the perioperative blood loss of 28 consecutive pediatric patients with idiopathic scoliosis who underwent posterior spinal fusion and received intraoperative EACA with 31 consecutive patients who did not receive this medication and served as a control group. Results. The patients in both groups were similar. Patients in the EACA group demonstrated statistically significant decreases in total estimated perioperative blood loss and the need for autologous blood transfusion. The patients in the EACA group had no intraoperative or postoperative complications related to the use of this medication. Conclusions. Based on these preliminary findings, we believe that EACA is helpful in decreasing blood loss in patients undergoing posterior spinal fusion and instrumentation, and may decrease the number of autologous units needed to maintain safe perioperative hemoglobin levels, thereby improving safety and lowering cost associated with scoliosis surgery.

Parental presence during anaesthesia induction for outpatient surgery of the infant

We conducted a randomized controlled trial of parental presence during anaesthesia induction for outpatient surgery in 73 infants (aged 1–12 months). Effects of parental presence on infant and parental outcomes, including anxiety, health care attitudes and satisfaction with the anaesthesia and surgery experience were evaluated. Results demonstrated that parental presence had no impact on infant behavioural distress during induction. In addition, parents who were present demonstrated comparable anxiety levels and health care attitudes before and after surgery, as well as comparable levels of satisfaction with the surgical experience compared to parents who were absent during induction. We discuss reasons for the lack of treatment effects from parental presence, and new directions for future research to identify subgroups of children who may most benefit from the opportunity to have parents involved in the perioperative period.

Assessment of risk factors for emergence distress and postoperative behavioural changes in children following general anaesthesia

Background:  Emergence distress commonly occurs in children recovering from the immediate effects of general anaesthesia. This study was performed to (1) examine whether parental presence in the operating room during emergence from anaesthesia reduces the incidence or severity of emergence distress behaviour, and (2) assess psychosocial risk factors, including child temperament and sleep behaviour, for development of emergence distress.

Intrathecal morphine for postoperative analgesia in patients with idiopathic scoliosis undergoing posterior spinal fusion.

Study Design. A retrospective study of postoperative pain management with intrathecal morphine. Objective. Identify the dosing regimen of intrathecal morphine that safely and effectively provides postoperative analgesia with minimal complications in patients with idiopathic scoliosis undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). Summary of Background Data. Postoperative pain after surgery for idiopathic scoliosis is a concern. Intrathecal morphine has been used to decrease pain. However, the most appropriate dose has not been determined. Methods. We retrospectively analyzed 407 consecutive patients with idiopathic scoliosis who underwent PSF and SSI at our institution from 1992 through 2006. Patients were divided into 3 groups based on the intrathecal morphine dose: no dose (n = 68); moderate dose of 9 to 19 &mgr;g/kg, mean 14 &mgr;g/kg (n = 293); and high dose of 20 &mgr;g/kg or greater, mean 24 &mgr;g/kg (n = 46). Data included demographics, Wong-Baker visual analog scale postoperative pain scores, postoperative intravenous morphine requirements, time to first rescue dose of intravenous morphine, and postoperative complications of pruritis, nausea/vomiting, respiratory depression, and pediatric intensive care unit (PICU) admission. Results. The demographics of the 3 study groups showed no statistical differences. The mean Wong-Baker visual analog scale pain score in the post anesthesia care unit was 5.2, 0.5, and 0.2, and the mean time to first morphine rescue was 6.6, 16.7, and 22.9 hours, respectively. In the first 48 postoperative hours, respiratory depression occurred in 1 (1.5%), 8 (2.7%), and 7 (15.2%) patients, whereas PICU admission occurred in 0 (0%), 6 (2%), and 8 (17.4%) patients, respectively. The majority of PICU admissions were the result of respiratory depression. Frequency of pruritis and nausea/vomiting was similar in all 3 groups. Conclusion. Intrathecal morphine in the moderate dose range of 9 to 19 &mgr;g/kg (mean 14 &mgr;g/kg), provides safe and effective postoperative analgesia in the immediate postoperative period for patients with idiopathic scoliosis undergoing PSF and SSI. Higher doses did not result in significantly better analgesia and had a greater frequency of respiratory depression requiring PICU admission.

Continuous intravenous morphine infusion for postoperative analgesia following posterior spinal fusion for idiopathic scoliosis.

Study Design. A retrospective study of postoperative pain management. Objective. Evaluate the efficacy and safety of continuous intravenous morphine infusion for postoperative pain management in patients with idiopathic scoliosis (IS) undergoing posterior spinal fusion (PSF) and segmental spinal instrumentation (SSI). Summary of Background Data. Postoperative pain is a common problem following surgery for IS. There are no published reports regarding the use of a continuous intravenous morphine infusion for this patient population. Methods. We retrospectively reviewed data regarding 339 consecutive patients with IS who underwent PSF and SSI between 1992 and 2006. All patients received intrathecal morphine after the induction of general anesthesia. Following surgery, preordered morphine infusion (0.01 mg/kg/h) was started at first reported pain. The infusion rate was titrated based on vital signs, visual analog scale (VAS) pain scores (0–10), and clinical status. It was continued until patients were able to take oral analgesics. We reviewed intrathecal morphine dosage, VAS pain scores through the third postoperative day, interval to start of morphine infusion, total morphine requirements in the first 48 hours, and any adverse reactions (nausea/vomiting, pruritus, respiratory depression, and pediatric intensive care unit admission). Results. Mean intrathecal morphine dose was 15.5 ± 3.9 &mgr;g/kg and mean interval to start of the intravenous morphine infusion was 17.5 ± 5 hours. Mean VAS pain scores were 3.1, 4.5, 4.5, and 4.6 at 12 hours, 1, 2, and 3 days after surgery, respectively. The total mean morphine dose in the first 48 hours postoperatively was 0.03 ± 0.01 mg/kg/h. Total morphine received was 1.44 ± 0.5 mg/kg. Nausea/vomiting and pruritus, related to the morphine infusion occurred in 45 patients (13.3%) and 14 patients (4.1%), respectively. No patients had respiratory depression or required Pediatric Intensive Care Unit admission. Conclusion. A low frequency of adverse events and a mean postoperative VAS pain score of 5 or less demonstrate that a continuous postoperative morphine infusion is a safe and effective method of pain management in patients with IS following PSF and SSI.

Current Status of Psychosocial Intervention Research for Pediatric Outpatient Surgery

We reviewed 20 published studies of psychosocial interventions (i.e., preoperative preparation, parental presence) for children undergoing outpatient surgical procedures. The effectiveness of different intervention strategies on child and parent outcomes is summarized. Few positive effects were found for any of the psychosocial interventions. However, only a small number of randomized controlled trials were conducted and many of the studies using quasi-experimental designs had significant methodological problems that limited the interpretation of their findings. Research recommendations are described such as strengthening methodological rigor, making intervention strategies relevant to outpatient surgery, and using developmentally appropriate intervention strategies.

intrathecal morphine attenuates acute opioid tolerance secondary to remifentanil infusions during spinal surgery in adolescents

Introduction The unique pharmacokinetic properties of remifentanil with a context-sensitive half-life unaffected by length of infusion contribute to its frequent use during anesthetic management during posterior spinal fusion in children and adolescents. However, its intraoperative administration can lead to increased postoperative analgesic requirements, which is postulated to be the result of acute opioid tolerance with enhancement of spinal N-methyl-D-aspartate receptor function. Although strategies to prevent or reduce tolerance have included the coadministration of longer acting opioids or ketamine, the majority of these studies have demonstrated little to no benefit. The current study retrospectively evaluates the efficacy of intrathecal morphine (ITM) in preventing hyperalgesia following a remifentanil infusion. Methods We retrospectively analyzed 54 patients undergoing posterior spinal fusion with segmental spinal instrumentation, to evaluate the effects of ITM on hyperalgesia from remifentanil. Patients were divided into two groups based on whether they did or did not receive remifentanil during the surgery: no remifentanil (control group) (n=27) and remifentanil (study group) (n=27). Data included demographics, remifentanil dose and duration, Wong–Baker visual analog scale postoperative pain scores, and postoperative intravenous morphine consumption in the first 48 postoperative hours. Results The demographics of the two study groups were similar. There were no differences in the Wong–Baker visual analog scale pain scores in the postanesthesia care unit and on postoperative days 1 and 3. Pain scores were higher in the remifentanil group on postoperative day 2 (2.9 vs 3.8). Postoperative morphine requirements were similar between the two groups (0.029 vs 0.017 mg/kg/48 h for the control group and the study group, respectively). Conclusion In patients receiving preincisional ITM during spinal surgery, intraoperative remifentanil does not increase postoperative analgesic requirements.

Intrathecal morphine analgesia in idiopathic scoliosis surgery: does sex or racial group affect optimal dosing?

Background We previously determined the intrathecal morphine optimal dose to maximize analgesia in patients undergoing idiopathic scoliosis surgery while minimizing adverse effects. Our purpose was to determine if this protocol was equally effective across sex and racial groups. Methods We studied 287 patients given a moderate dose of intrathecal morphine of 9 to 19 &mgr;g/kg (mean 14 &mgr;g/kg): 240 female and 47 male patients and 224 White (W) and 63 African-American (AA) patients. Factors analyzed included postoperative visual analog pain scores (VAS), time to first opioid dose, total morphine over the first 48 hours, and postoperative complications of respiratory depression requiring pediatric intensive care unit (PICU) admission, nausea/vomiting and pruritis. Results For female and male patients, mean VAS pain scores in postanesthesia care unit (PACU) were 0.48±1.14 and 0.56±1.16, mean times to first opioid dose were 16.65±4.38 and 16.72±4.97 hours, and total morphine over the first 48 hours were 1.49±0.53 and 1.49±0.58 mg/kg, respectively. Respiratory depression and PICU admission occurred in 10 of 240 female (4.1%) and 3 of 47 male (6.4%) patients. Minor complications of nausea/vomiting and pruritis occurred in 78 of 240 female (31.7%) and 12 of 47 male (25.5%) patients. For W and AA patients, mean VAS pain scores in PACU were 0.48±1.10 and 0.46±1.13, mean times to first opioid dose were 16.53±3.77 and 17.12±6.05 hours, and total morphine over the first 48 hours were 1.54±0.53 and 1.30±0.53 mg/kg, respectively. Respiratory depression and PICU admission occurred in 9 of 224 W (4.0%) and 4 of 63 AA (6.3%) patients. Nausea/vomiting and pruritis occurred in 77 of 224 W (34.4%) and 11 of 63 AA (17.5%) patients, respectively. Conclusions Intrathecal morphine results in safe and effective for postoperative pain relief in patients undergoing surgery for idiopathic scoliosis irregardless of sex or race. Level of Evidence III, retrospective comparative study.

Cardiac arrest in a child with cerebral palsy undergoing sevoflurane induction of anesthesia after preoperative clonidine

Clonidine is a frequently administered α2‐adrenergic agonist which can decrease heart rate and blood pressure. We present a case of a 5‐year‐old child with cerebral palsy and seizure disorder, receiving clonidine for restlessness, who presented for placement of a baclofen pump. Without the knowledge of the medical personnel, the patients mother administered three doses of clonidine during the evening before and morning of surgery to reduce anxiety. During induction of anesthesia, the patient developed bradycardia and hypotension requiring cardiac resuscitation. There are no previous reports of clonidine‐associated cardiac arrest in a child undergoing induction of anesthesia.

Automatic atrial tachycardia in an infant following general anesthesia

Automatic atrial tachycardia (AAT) is a rare supraventricular tachyarrhythmia (<10% of all supraventricular tachycardias), which can present in infants or young children. There are no published reports of AAT occurring in an infant or child following noncardiac surgery and general anesthesia. This report describes the management of a previously healthy 5‐month‐old infant, who developed AAT in the postanesthesia care unit following an uneventful circumcision under general anesthesia.