Analgesic effects of methadone and magnesium following posterior spinal fusion for idiopathic scoliosis in adolescents: a randomized controlled trial.

PURPOSE: To provide optimal conditions for neurophysiological monitoring and rapid awakening, remifentanil is commonly used during pediatric spinal surgery. However, remifentanil may induce hyperalgesia and increase postoperative opioid requirements. We evaluated the potential of methadone or magnesium to prevent remifentanil-induced hyperalgesia. METHODS: Using a prospective, randomized, blinded design, adolescents presenting for posterior spinal fusion to treat idiopathic scoliosis were assigned to receive desflurane with remifentanil alone (REMI), remifentanil + methadone (MET) (0.1 mg/kg IV over 15 min), or remifentanil + magnesium (MAG) (50 mg/kg bolus over 30 min followed by 10 mg/kg/h). Primary outcomes were opioid requirements and postoperative pain scores. Secondary outcomes included intraoperative anesthetic requirements, neurophysiological monitoring conditions, and emergence times. RESULTS: Data analysis included 60 patients. Total opioid requirement (hydromorphone) in the REMI group (received perioperatively and on the inpatient ward) was 0.34 ± 0.11 mg/kg compared to 0.26 ± 0.10 mg/kg in the MET group (95% confidence interval (CI) of difference: - 0.14, - 0.01; p = 0.035). The difference in opioid requirements between the REMI and MET group was related to intraoperative dosing (0.04 ± 0.02 mg/kg vs. 0.02 ± 0.01 mg/kg; 95% CI of difference: - 0.01, - 0.02; p = 0.003). No difference was noted in pain scores, and no differences were noted when comparing the REMI and MAG groups. CONCLUSION: With the dosing regimens in the current study, the only benefit noted with methadone was a decrease in perioperative opioid requirements. However, given the potential for hyperalgesia with the intraoperative use of remifentanil, adjunctive use of methadone appears warranted.

Preliminary Indications for the Use of Sugammadex After Its Addition to a Formulary at a Tertiary Care Children's Hospital.

OBJECTIVES: Neuromuscular blocking agents (NMBAs) are administered to facilitate endotracheal intubation and provide skeletal muscle relaxation in surgical procedures. Sugammadex (Bridion) recently received approval by the United States Food and Drug Administration for reversal of rocuronium and vecuronium-induced neuromuscular blockade thereby providing an alternative to acetylcholinesterase inhibitors such as neostigmine. This quality improvement analysis sought to investigate the clinical reasons and common clinical perceptions for choosing sugammadex over neostigmine to reverse NMBAs. METHODS: One hundred cases were reviewed where sugammadex was used for neuromuscular blockade reversal in the operating room. Cases were identified from electronic medical record reports. Anesthesia providers responsible for administering sugammadex were interviewed to obtain rationales for sugammadex use in the perioperative setting. Responses were reviewed to identify distinct reasons for using sugammadex. Two independent raters ranked the reasons according to prevalence. The study was exempt from Institutional Review Board approval as a quality improvement (QI) project. RESULTS: Forty-two anesthesia providers (15 Certified Registered Nurse Anesthetists, 5 anesthesiology trainees, and 22 attending anesthesiologists) were interviewed to identify reasons why sugammadex was administered intraoperatively in 100 surgical cases (69/31 male/female patients, age 9.4 ± 6.5 years). The author identified the top 19 common reasons respondents chose to use sugammadex for each case, and independent raters reviewed the response summaries for those 19 primary reasons sugammadex was used. The most common reasons for choosing sugammadex were: 1) beneficial pharmacokinetics of the agent; 2) sugammadex's perceived superior efficacy over neostigmine; and 3) concerns regarding adverse effects of neostigmine and/or the anticholinergic agent. CONCLUSIONS: Sugammadex has recently been introduced for clinical use to reverse NMBAs at our institution. Primary reasons and perceptions for its use over neostigmine included a limited adverse effect profile, a greater sense of control and predictability of patients' response, and a limited incidence of residual neuromuscular blockade.

Double-Blind Randomized Placebo-Controlled Trial of Single-Dose Intravenous Acetaminophen for Pain Associated With Adenotonsillectomy in Pediatric Patients With Sleep-Disordered Breathing.

OBJECTIVES: Adequate pain control is an important component in the postoperative outcome for pediatric adenotonsillectomy patients with sleep-disordered breathing (SDB). Intravenous acetaminophen appears to be a favorable analgesic adjunct owing to its predictable pharmacokinetics and opioid-sparing effects; however, its role in pediatric adenotonsillectomy pain management remains unclear. METHODS: In this prospective, randomized, double-blinded, controlled study, subjects with the diagnosis of SDB, aged 2 to 8 years, who required extended postoperative admission, received intravenous acetaminophen (15 mg/kg) or saline placebo intraoperatively in addition to morphine (0.1 mg/kg) for postoperative surgical analgesia. Pain scores in the postanesthesia care unit (PACU) using the FLACC (Faces, Leg, Activity, Cry, Consolability) score were used to determine the need for supplemental analgesic agents in the PACU. The PACU time and time to the first request for pain medication on the inpatient ward were also measured. RESULTS: A total of 239 patients were included in the final data analysis (118 in the intravenous acetaminophen group and 121 in the saline placebo group). The 2 groups did not differ in the proportion of patients reaching FLACC scores = 4 in the PACU (p = 0.223); mean FLACC scores in the PACU (p = 0.336); mean PACU time (p = 0.883); or time to requesting pain medication on the inpatient ward (p = 0.640). CONCLUSIONS: A single intraoperative dose of intravenous acetaminophen did not alter the postoperative course of pediatric patients with SDB following adenotonsillectomy.

Effects of partial sleep deprivation on reaction time in anesthesiologists.

BACKGROUND: Fatigue in anesthesiologists may have implications that extend beyond individual well-being. AIM: The aim of the present study was to evaluate the impact of sleep deprivation on the reaction time in anesthesiologists either after an overnight call or regular working hours. Moderation of this effect by coping strategies was observed. METHODS: Psychomotor vigilance test was used to assess reaction time in 23 anesthesiologists at two time-points: (i) on a regular non-call day and (ii) after a 17-h in-house call. Student's paired t-test was used to compare Psychomotor Vigilance Task data at these two moments. Change score regression was performed to determine the association between coping strategies, assessed using the Coping Strategy Indicator instrument, and decline in reaction time after night call. RESULTS: Twenty-one colleagues completed the psychomotor vigilance test measurements after two decided to end their participation for personal reasons. Post-call psychomotor vigilance test mean reaction time decreased by an average of 31.2 ms (95% CI: 0.5, 61.9; P = 0.047) when compared to regular day. Reliance on specific coping mechanisms, indicated by Coping Strategy Indicator scale scores, included problem-solving (28 ± 4), followed by seeking social support (23 ± 5) and avoidance (19 ± 4). The change score regression model (r2 = 0.48) found that greater reliance on avoidance was associated with greater increase in reaction time after night call. CONCLUSION: Reaction time increased considerably in anesthesiologists after a night call duty. Greater subjective reliance on avoidance as a coping strategy was associated with greater deterioration in performance.

Etiology of postanesthetic and postsedation events on the inpatient ward: data from a rapid response team at a tertiary care children's hospital.

INTRODUCTION: The goal of this study was to identify the etiology of events and demographics of patients that experience complications requiring activation of the Rapid Response Team (RRT) during the first 24 h following anesthetic care. METHODS: We performed a retrospective review of the Quality Improvement database from the Department of Anesthesiology & Pain Medicine at Nationwide Children's Hospital. The database was searched to identify those patients who had a RRT evaluation activated within 24 h of receiving anesthesia or procedural sedation. These patients' charts were reviewed to obtain demographic information, etiology of the RRT call, and outcomes. RESULTS: The study cohort included 106 RRT calls that were made over a 3-year period. Six patients were excluded from analysis due to incomplete datasets. One hundred patients remained for analysis including 60 males and 40 females. Patients ranged in age from 0.08 to 31.21 years (7.8 ± 7.7 years, median 5.3 years). Seventy-one patients were American Society of Anesthesiologists' (ASA) status 3 or 4 and 29 patients were ASA status 1 or 2. Five calls were made for patients who had undergone procedural sedation while the other 95 were on patients who received general anesthesia. The average time to the RRT call after the end of anesthetic care was 11.4 ± 6.6 h. Respiratory concern was the most common reason for RRT initiation, accounting for 71 of the 100 calls. Forty-nine patients had a recent respiratory illness, chronic respiratory-related disease, or history of preterm birth. Fifty patients (50%) were transferred to a higher level of care following the RRT consult. There was no significant difference between age, gender, ASA status, or etiology of the event for patients transferred vs. those who were not. A significant difference was noted in the Pediatric Early Warning Score of patients transferred to a higher level of care in comparison to patients who remained on the floor (4 ± 2 vs. 3 ± 2, P = 0.0097). CONCLUSION: RRT calls were most common for respiratory concerns. High ASA status, general anesthesia administration, and the presence of acute or chronic conditions prior to anesthetic administration predispose a patient to perioperative complications resulting in the need for an RRT call.

Time to talk about work-hour impact on anesthesiologists: The effects of sleep deprivation on Profile of Mood States and cognitive tasks.

BACKGROUND: A physician's fatigue raises significant concerns regarding personal and patient safety. Effects of sleep deprivation on clinical performance and the quality of patient care are major considerations of today's health care environment. AIM: To evaluate the impact of partial sleep deprivation after a 17-h overnight call (3 pm-7 am) on the mood status and cognitive skills of anesthesiologists in an academic clinical hospital setting, as compared to these parameters during regular working hours. METHODS: Taking circadian rhythm into account, the following measures were assessed in 21 pediatric anesthesiologists at two time points over the course of the study; (i) between 7 and 8 am on a regular non call day, and (ii) between 7 and 8 am after a 17-h in-house call (3 pm-7 am). Six mood states were assessed using the Profile of Mood States. A Total Mood Disturbance (TMD) score was obtained as the sum of all mood scores minus vigor. The total score provides a global estimate of affective state. Simple cognitive tests were similarly administered to assess cognitive skills. A two-tailed paired t-test was used to compare data between regular and post call days. A P < 0.05 was used. RESULTS: The study cohort included 21 pediatric anesthesiologists at a tertiary care children's hospital. Tension, anger, fatigue, confusion, TMD, irritability, feeling jittery, and sleepiness were significantly affected (P < 0.05). A decrease in vigor, energy, and confidence was observed after a night call shift (P < 0.05). There was also a decrease in being "talkative" after the call shift (P < 0.05). CONCLUSION: Partial sleep deprivation affects the total mood status of anesthesiologists and impacts their cognitive skills. These findings are particularly relevant in a context of increased work expectation, particularly on clinical performance in our modern medical system. Such observations suggest that there may be changes that impact the safety of our patients and the quality of health care that is provided.

Ventilation during laparoscopic-assisted bariatric surgery: volume-controlled, pressure-controlled or volume-guaranteed pressure-regulated modes.

INTRODUCTION: Managing ventilation and oxygenation during laparoscopic procedures in severely obese patients undergoing weight loss surgery presents many challenges. Pressure-controlled ventilation, volume-guaranteed (PCV-VG) is a dual-control mode of ventilation and an alternative to pressure (PC) or volume (VC) controlled ventilation. PCV-VG features a user-selected tidal volume target, that is auto-regulated and pressure controlled. We hypothesized that PCV-VG ventilation would provide improved oxygenation and ventilation during laparoscopic bariatric surgery with a lower peak inflating pressure (PIP) than either PC or VC ventilation. METHODS: This was a prospective cross-over cohort trial (n = 20). In random sequence each patient received the three modes of ventilation for 20 minutes during the laparoscopic portion of the procedure. For all modes of ventilation the goal tidal volume was 6-8 mL/kg, and the respiratory rate was adjusted to achieve normocarbia. The PIP, exhaled tidal volume, respiratory rate, and oxygen saturation were recorded every five minutes. At the end of 20 minutes, an arterial blood gas was obtained. Data were analyzed using a paired t-test. RESULTS: PCV-VG and PC ventilation both resulted in significantly lower PIP (cmH2O) than VC ventilation (30.5 ± 3.0, 31.6 ± 4.9, and 36.3 ± 3.4 mmHg respectively; p < 0.01 for PCV-VG vs. VC and PC vs. VC). There was no difference in oxygenation (PaO2), ventilation (PaCO2) or hemodynamic variables between the three ventilation modes. CONCLUSIONS: In adolescents and young adults undergoing laparoscopic bariatric surgery, PCV-VG and PC were superior to VC ventilation in their ability to provide ventilation with the lowest PIP.

Accuracy of the CNAP™ monitor, a noninvasive continuous blood pressure device, in providing beat-to-beat blood pressure measurements during bariatric surgery in severely obese adolescents and young adults.

BACKGROUND: During perioperative care, the continuous measurement of blood pressure (BP) provides superior physiological monitoring compared to intermittent techniques, especially for patients with comorbid conditions such as severe obesity. The current study prospectively assesses the accuracy of a continuous, noninvasive BP device in severely obese adolescents and young adults. METHODS: The technology evaluated was the CNAP Monitor 500, developed by CNSystems AG (Graz, Austria). The study cohort was composed of severely obese adolescents (body mass index ≥ 35 kg/m(2)) undergoing a surgical weight loss procedure (robotically assisted or laparoscopic vertical sleeve gastrectomy or laparoscopic Roux-en-Y gastric bypass). Systolic (sBP), diastolic (dBP), and mean arterial (MAP) blood pressure readings were captured from an intraoperatively placed radial arterial cannula (AC) and the CNAP device at regular intervals (once per minute) during anesthetic care. RESULTS: The study cohort consisted of 18 severely obese subjects undergoing weight loss surgery. A total of 2,159 pairs each of sBP, dBP, and MAP values obtained. The correlation coefficient between the AC and the CNAP device was 0.655, 0.667, and 0.783 for the sBP, dBP, and MAP, respectively. The CNAP values (sBP, dBP, MAP) were ≤5 mmHg from the AC values in 33, 40, and 41% of the values, respectively. The difference was more than 10 mmHg (sBP, dBP, MAP) in 39, 28, and 25% of the values, respectively. Using a Bland-Altman analysis, the precision and bias for the sBP, dBP, and MAP were 0.3 ± 14.2, -1.3 ± 9.5, and -0.6 ± 8.6 mmHg, respectively. CONCLUSION: When compared to previous studies in the adult population, the accuracy of the CNAP device in a cohort of severely obese adolescents undergoing weight loss surgery was slightly less than previously reported. The current data demonstrate a clinically useful trend of the CNAP device with arterial values in this challenging patient population in whom an arterial cannula may at times be difficult.

Pain management following myringotomy and tube placement: intranasal dexmedetomidine versus intranasal fentanyl.

PURPOSE: Despite the brevity of the procedure, bilateral myringotomy and tympanostomy tube placement (BMT) can result in significant postoperative pain and discomfort. As the procedure is frequently performed without intravenous access, non-parenteral routes of administration are frequently used for analgesia. The current study prospectively compares the efficacy of intranasal (IN) dexmedetomidine with IN fentanyl for children undergoing BMT. METHODS: This prospective, double-blinded, randomized clinical trial included pediatric patients undergoing BMT. The patients were randomized to receive either IN dexmedetomidine (1 µg/kg) or fentanyl (2 µg/kg) after the induction of general anesthesia with sevoflurane. All patients received rectal acetaminophen (40 mg/kg) and the first 50 patients also received premedication with oral midazolam. Postoperative pain and recovery were assessed using pediatric pain and recovery scales, and any adverse effects were monitored for. RESULTS: The study cohort included 100 patients who ranged in age from 1 to 7.7 years and in weight from 8.6 to 37.4 kg. They were divided into 4 groups with 25 patients in each group: (1) midazolam premedication+IN dexmedetomidine; (2) midazolam premedication+IN fentanyl; (3) no premedication+IN dexmedetomidine; and (4) no premedication+IN fentanyl. Pain scores were comparable when comparing groups 2, 3 and 4, but were higher in group 1 (midazolam premedication with IN dexmedetomidine). There was no difference in total time in the post-anesthesia care unit (PACU) or time from arrival in the PACU until hospital discharge between the 4 groups. The heart rate (HR) was significantly lower in group 3 when compared to the other groups at several different times after arrival to the PACU. No clinically significant difference was noted in blood pressure. CONCLUSION: Following BMT, when no premedication is administered, there was no clinical advantage when comparing IN dexmedetomidine (1 µg/kg) to IN fentanyl (2 µg/kg). The addition of oral midazolam as a premedication worsened the outcome measures particularly for children receiving IN dexmedetomidine.

Transportation of patients following surgery for congenital heart disease: a process review prompted by the opening of a new hospital.

The decision to extubate the trachea of patients in the operating room prior to transport must balance the relative risks and advantages of transporting patients with an unsecured airway versus the problems associated with maintaining sedation and tracheal intubation during transport. Children with congenital heart disease often benefit from early tracheal extubation and this has been the standard of practice at our institution. However, the recent expansion and opening of a new hospital increased the distance from the cardiac operating rooms to the cardiothoracic intensive care unit and provided an opportunity for us to further evaluate our clinical practice. In order to better understand our practice and prepare for the opening of the new hospital, we conducted a prospective observational quality improvement project to evaluate the hemodynamic and respiratory parameters of postoperative patients undergoing transportation both before and after the move to the new hospital. The study cohort included 115 patients who ranged in age from 2 days to 25 years and in weight from 2.2 to 104 kilograms. Our analysis showed no significant change in our practice of early tracheal extubation. We noted no clinically significant changes in the monitored physiologic variables, despite the increase in the overall transport time. We believe that this transition and the ongoing safety of our practice were facilitated by significant preparation prior to the move including transport simulations.

Cuffed endotracheal tubes in infants and children: a technique to continuously measure the intracuff pressure.

OBJECTIVES: Various devices have been used to measure the intracuff pressure (CP) of an endotracheal tube at the time of inflation; however, no device has found widespread acceptance for the continuous monitoring of CP. We devised a simple method to continuously measure the CP using an invasive pressure monitoring setup (IPMS), which is used routinely in the operating room to monitor arterial or central venous pressures. The accuracy of the device was compared to those obtained from a commercially available and clinically used manometer (MM). METHODS: Size 4.0, 5.0 and 6.0 mm ID cETTs were placed into one of 3 sizes of polyvinylchloride (PVC) tubes. The cuff of the cETT was inflated after inserting the cETT into the PVC pipes. After inflation, the CP was simultaneously checked using the MM and the IPMS. A total of 100 simultaneous (IPMS and MM) readings were obtained from each of the 3 sizes of cETT with the intracuff pressure randomly varying between 10 and 40 cmH2O. Statistical analysis included a Bland-Altman comparison to determine the bias, mean, and 95% levels of agreement (LOA), and a linear regression analysis. RESULTS: Linear regression analysis demonstrated an R(2) value of 0.988, 0.9899, and 0.9879 when comparing the pressure from the IPMS and MM from the 4.0, 5.0 and 6.0 mm cETT, respectively. CONCLUSIONS: A standard IPMS can be used to continuously monitor intracuff pressure with the use of a cETT. Although various techniques can be used safely to avoid hyperinflation of the cuff, they provide only an instantaneous measure of the CP. The current technique allows for continuous monitoring of CP during prolonged cases or in other clinical scenarios when such monitoring is required.

Accuracy of the CNAP monitor, a noninvasive continuous blood pressure device, in providing beat-to-beat blood pressure readings in the prone position.

STUDY OBJECTIVE: To assess the accuracy of a noninvasive continuous arterial pressure (CNAP) monitor in patients who are positioned prone in the operating room. DESIGN: Prospective study. SETTING: Operating room at a children's hospital. PATIENTS: 20 pediatric patients, aged 13.8 ± 2 years, and weight 63.7 ± 18.8 kg, scheduled for surgery in the prone position, and for which arterial catheter placement was planned. INTERVENTIONS: Measurements were recorded with an arterial line (AL) and a new noninvasive continuous blood pressure (BP) monitor. MEASUREMENTS: Systolic (SBP), diastolic (DBP), and mean arterial (MAP) pressure readings were captured from an arterial cannula and the CNAP device every minute during anesthesia. MAIN RESULTS: The study cohort consisted of analysis of 4104 pairs of SBP, DBP, and MAP values, which showed an absolute difference between the AL and CNAP device readings of 7.9 ± 6.3 mmHg for SBP, 5.3 ± 4.3 mmHg for DBP, and 4.6 ± 3.9 mmHg for MAP. Bland-Altman analysis of MAP values showed a bias of 0.26 mmHg, with upper and lower limits of agreement of 12.18 mmHg and -11.67 mmHg, respectively. CNAP readings deviated from arterial values by ≤ 5 mmHg in 67% of MAP values, 59% of DBP values, and 43% of SBP readings. The difference was ≤ 10 mmHg for 94% of MAP readings, 90% of DBP values, and 73% of SBP readings. CONCLUSIONS: During prone positioning, the CNAP monitor provided clinically acceptable accuracy for MAP values, similar to those reported in adults in the supine position.

The role of different anesthetic techniques in altering the stress response during cardiac surgery in children: a prospective, double-blinded, and randomized study.

OBJECTIVES: Our goal was to evaluate the role of three anesthetic techniques in altering the stress response in children undergoing surgery for repair of congenital heart diseases utilizing cardiopulmonary bypass in the setting of fast tracking or early tracheal extubation. Furthermore, we wanted to evaluate the correlation between blunting the stress response and the perioperative clinical outcomes. DESIGN: Prospective, randomized, double-blinded study. SETTING: Single center from December 2008 to May of 2011. PATIENTS: Forty-eight subjects (low-dose fentanyl plus placebo, n = 16; high-dose fentanyl plus placebo, n = 17; low-dose fentanyl plus dexmedetomidine, n = 15) were studied between ages 30 days to 3 years old who were scheduled to undergo repair for a ventricular septal defect, atrioventricular septal defect, or Tetralogy of Fallot. METHODS: Children undergoing surgical repair of congenital heart disease were randomized to receive low-dose fentanyl (10 mcg/kg; low-dose fentanyl), high-dose fentanyl (25mcg/kg; high-dose fentanyl), or low-dose fentanyl plus dexmedetomidine (as a 1 mcg/kg loading dose followed by infusion at 0.5mcg/kg/hr until separation from cardiopulmonary bypass. In addition, patients received a volatile anesthetic agent as needed to maintain hemodynamic stability. Blood samples were tested for metabolic, hormonal and cytokine markers at baseline, after sternotomy, after the start of cardiopulmonary bypass, at the end of the procedure and at 24 hours postoperatively. MEASUREMENTS AND MAIN RESULTS: Forty-eight subjects (low-dose fentanyl plus placebo, n = 16; high-dose fentanyl plus placebo, n = 17; low-dose fentanyl plus dexmedetomidine, n = 15) were studied. Subjects in the low-dose fentanyl plus placebo group had significantly higher levels of adrenocorticotropic hormone, cortisol, glucose, lactate, and epinephrine during the study period. The lowest levels of stress markers were seen in the high-dose fentanyl plus placebo group both over time (adrenocorticotropic hormone, p= 0.01; glucose, p = 0.007) and at individual time points (cortisol and lactate at the end of surgery, epinephrine poststernotomy; p < 0.05). Subjects in the low-dose fentanyl plus dexmedetomidine group had lower lactate levels at the end of surgery compared with the low-dose fentanyl plus placebo group (p < 0.05). Although there were no statistically significant differences in plasma cytokine levels between the three groups, the low-dose fentanyl plus placebo group had significantly higher interleukin-6:interleukin-10 ratio at 24 hours postoperatively (p < 0.0001). In addition, when compared with the low-dose fentanyl plus placebo group, the low-dose fentanyl plus dexmedetomidine group showed a lower norepinephrine level from baseline at poststernotomy, after the start of cardiopulmonary bypass, and at the end of surgery (p ≤ 0.05). Subjects in the low-dose fentanyl plus placebo group had more postoperative narcotic requirement (p = 0.004), higher prothrombin time (p ≤ 0.03), and more postoperative chest tube output (p < 0.05). Success of fast tracking was not significantly different between groups (low-dose fentanyl plus placebo 75%, high-dose fentanyl plus placebo 82%, low-dose fentanyl plus dexmedetomidine 93%; p = 0.39). CONCLUSIONS: The use of low-dose fentanyl was associated with the greatest stress response, most coagulopathy, and highest transfusion requirement among our cohorts. Higher dose fentanyl demonstrated more favorable blunting of the stress response. When compared with low-dose fentanyl alone, the addition of dexmedetomidine improved the blunting of the stress response, while achieving better postoperative pain control.

Changes in tissue oxygenation following caudal epidural blockade in infants and children.

BACKGROUND: Adequate tissue oxygenation is required for effective white blood cell function and bactericidal activity. Decreased tissue oxygenation has been shown to be a risk factor for perioperative wound infections. Regional anesthetic techniques result in a functional sympathetic block and may increase tissue oxygenation. The purpose of the current study is to prospectively evaluate changes in tissue oxygenation using a non-invasive near-infrared spectroscopy (NIRS) device following caudal epidural block in infants and children. METHODS: Following standard anesthetic induction and general anesthesia with an endotracheal tube or laryngeal mask airway, the NIRS sensors were placed on two sites. One sensor was placed at a site affected by the caudal block (lower extremity), and the other sensor was placed on the arm, a site unaffected by the caudal block (upper extremity). The NIRS value was recorded at baseline and then again at 15, 30, and 45 min after the block. The caudal block was performed, after anesthetic induction and NIRS sensor placement, using bupivacaine 0.25% with epinephrine 1 : 200,000 or ropivacaine 0.2% with epinephrine 1 : 200,000 at a dose of 1 ml · kg(-1). The inspired oxygen concentration after induction was held constant at 30%, and anesthesia was maintained with sevoflurane at 1 MAC. No other pharmacologic agents were administered. RESULTS: Following the caudal epidural block, there was a statistically significant increase in the tissue oxygenation from the affected site. The NIRS value increased from a baseline of 83 ± 4 to 87 ± 3 at 15 min (P = 0.0001 vs baseline), 88 ± 4 at 30 min (P < 0.0001 vs baseline), and 87 ± 4 at 45 min (P < 0.0001 vs baseline). No change was noted on the unaffected site (upper extremity). CONCLUSION: There was a statistically significant increase in tissue oxygenation as measured by NIRS following caudal anesthesia in infants and children. Although the magnitude of the change was less, this study confirms the results of previous studies in adults showing an increase in tissue oxygenation following regional blockade.