Remifentanil, fentanyl, and cardiac surgery: a double-blinded, randomized, controlled trial of costs and outcomes

Correlation between pain rating index and end-tidal sevoflurane concentration during sevoflurane anesthesia

Objective

To investigate the correlation between the pain rating index (PRi), which is an index derived from processed electroencephalography signals, and the end-tidal sevoflurane concentration (ETsevo).

Methods

This study involved 50 adults with a body mass index of 18 to 25 kg/m² who were undergoing elective surgery under general anesthesia. Thyrocricocentesis was performed with 2.5 mL of 2% tetracaine for endotracheal surface anesthesia, and intravenous injections of midazolam, etomidate, and rocuronium were then administered. The patients’ tracheas were intubated and their ventilatory rate was adjusted to maintain the partial pressure of end-tidal carbon dioxide at 30 to 35 mmHg. Anesthesia was maintained with sevoflurane. The ETsevo was adjusted to maintain anesthesia at 0.6, 0.8, 1.0, and 1.2 minimum alveolar concentration for 15 minutes each, and the PRi, mean arterial pressure (MAP), and heart rate were recorded at each concentration.

Results

A negative correlation was found between the PRi and ETsevo (−0.882) and between the MAP and ETsevo (−0.571). A low positive correlation was found between the PRi and MAP (0.484).

Conclusions

The PRi showed a high negative correlation with the ETsevo. Therefore, the PRi can be used to guide the depth regulation of sevoflurane anesthesia.

Clinical trial registration number: ChiCTR-IPR-17012092

Effect of remifentanil on intraoperative fluid balance: a retrospective statistical examination of factors contributing to fluid balance

Background

Postoperative fluid retention is a factor that causes delay in recovery and unexpected adverse events. It is important to prevent intraoperative fluid retention, which is putatively caused by intraoperative release of stress hormones, such as ADH (anti-diuretic hormone) or others. We hypothesized that intraoperative analgesia may prevent pathological fluid retention. We retrospectively explored the relationship between analgesics and in-out balance in surgical patients from anesthesia records.

Methods

Anesthetic records of 80 patients who had undergone orthognathic surgery were checked in this study. Patients were anesthetized with either TIVA (propofol and remifentanil) or inhalational anesthesia (sevoflurane and remifentanil). During surgery, acetated Ringer's solution was infused for maintenance at a rate of 3-5 ml/kg/h at the discretion of the anesthetist. The perioperative parameters, including the amount of crystalloid and colloid infused, and the amount of urine and bleeding were checked. Furthermore, we checked the amount and administration rate of remifentanil during the surgical procedure. The correlation coefficient between the remifentanil dose and the in-out balance or the urinary output was analyzed using the Pearson correlation coefficient. The contributing factor to fluid retention, including urinary output, was statistically examined by means of multivariate logistic regression analysis.

Results

A significant positive correlation was found between remifentanil dose and urinary output. Urinary output less than 0.04 ml/kg/min was suggested to cause positive fluid balance. Although in-out balance approaches zero balance with increase in remifentanil administration rate, no contributing factor for near-zero fluid balance was statistically picked up. The remifentanil administration rate was statistically picked up as the significant factor for higher urinary output (> 0.04 ml/kg/min) (OR, 2,644; 95% CI, 3.2-2.2 × 10⁶) among perioperative parameters.

Conclusions

In conclusion, remifentanil contributes in maintaining the urinary output during general anesthesia. Although further prospective study is needed to confirm this hypothesis, it was suggested that fluid retention could be avoided through suppressing intraoperative stress response by means of appropriate maintenance of remifentanil infusion rate.

Remifentanil and sevoflurane based anesthesia combined with bilateral erector spinae plane block in patients undergoing off-pump coronary artery bypass graft surgery

Introduction

Working on the institutional Enhanced Recovery After Surgery (ERAS Cardio) protocol for off-pump coronary artery bypass graft surgery (OP-CABG) we have noticed that patients treated according to the modified anesthesia protocol had not only significantly shorter time of respiratory support and intensive care unit stay but also lower postoperative troponin T concentration than patients who had standard fentanyl/sevoflurane-based anesthesia.

Aim

To compare the perioperative course of patients undergoing OP-CABG surgery and receiving standard fentanyl/sevoflurane anesthesia and those anesthetized according to the institutional ERAS Cardio protocol with remifentanil, sevoflurane, and bilateral extensor spinae plane (ESP) block.

Material and methods

Design: a prospective, open-label, observational study performed in a tertiary health center. Participants: 30 consecutive patients undergoing off-pump coronary bypass graft surgery. Interventions: 15 patients had standard anesthesia with etomidate, fentanyl, and rocuronium for induction and fentanyl/sevoflurane for maintenance (standard group); 15 others had bilateral single shot ESP block, then etomidate, remifentanil and rocuronium for induction, and remifentanil/sevoflurane for maintenance of anesthesia.

Results

Median time to extubation was 7.6 (5.5–12.5) h and 1.7 (1–3.25) h in “standard care” and ERAS groups, respectively (p = 0.00002). Length of stay in the intensive care unit was also shorter for patients in the ERAS group 20.5 (18–24) vs. 48 (42–48) h (p = 0.00001). Troponin concentration increased to a lesser extent in patients from the ERAS group: an increase of 151.8 (71.9–174.3) ng/ml vs. 253.8 (126.6–373.1) ng/ml, p = 0.008.

Conclusions

Remifentanil/sevoflurane anesthesia combined with bilateral ESP block shortens mechanical ventilation time and ICU stay, and decreases postoperative troponin-T concentration in patients undergoing off-pump coronary bypass graft surgery.

Remifentanil-Sparing Effect of Pectoral Nerve Block Type II in Breast Surgery under Surgical Pleth Index-Guided Analgesia during Total Intravenous Anesthesia

The pectoral nerve block type II (Pecs II block) can provide adequate perioperative analgesia in breast surgery. The surgical pleth index (SPI) is used to monitor the nociception balance using pulse oximetry. We investigated the remifentanil-sparing effect of Pecs II block under SPI guided analgesia during total intravenous anesthesia (TIVA). Thirty-nine patients undergoing breast surgery under remifentanil-propofol anesthesia were randomly assigned to the intervention (Pecs group, n = 20) or control group (n = 19). Remifentanil and propofol concentrations were adjusted to maintain an SPI of 20–50 and a bispectral index of 40–60, respectively. The Pecs group received an ultrasound-guided Pecs II block preoperatively using 30 mL of 0.5% ropivacaine. Total infused remifentanil during the surgery was significantly less in the Pecs group than in the control group (6.8 ± 2.2 μg/kg/h vs. 10.1 ± 3.7 μg/kg/h, p = 0.001). Pain scores on arrival at the postanesthetic care unit (PACU) (3 (2–5) vs. 5 (4–7)) and the rescue analgesic requirement in the PACU (9 vs. 2) was significantly lower in the Pecs group than in the control group. In conclusion, Pecs II block was able to reduce the intraoperative remifentanil consumption by approximately 30% and improve the postoperative pain in PACU in patients undergoing breast surgery under SPI-guided analgesia during TIVA.

A clinical trial comparing ultrasound-guided ilioinguinal/iliohypogastric nerve block to transversus abdominis plane block for analgesia following open inguinal hernia repair

OBJECTIVE

To compare the efficacy of ilioinguinal/iliohypogastric (IINB) nerve block to transversus abdominis plane (TAP) block in controlling incisional pain after open inguinal hernia repair.

PATIENTS AND METHODS

This was a prospective randomized clinical trial of 90 patients who received either IINB (N=45) or TAP block (N=45) using 0.2% bupivacaine 15 mL under ultrasound (US) guidance based on a random assignment in the postanesthesia care unit after having an open repair of inguinal hernia. Numeric Rating Scale (NRS) scores were recorded immediately following, 4, 8, 12, and 24 hours after completion of the block. NRS scores at rest and during movement were recorded 24, 36, and 48 hours after surgery. Analgesic satisfaction level was also evaluated by a Likert-based patient questionnaire.

RESULTS

NRS scores were lower in the IINB group compared to the TAP block group both at rest and during movement. The difference in dynamic pain scores was statistically significant (P=0.017). In addition, analgesic satisfaction was significantly greater in the IINB group than the TAP block group (mean score 2.43 vs 1.84, P=0.001). Postoperative opioid requirements did not differ between the two groups.

CONCLUSION

This study demonstrated that compared to TAP block, local blockade of ilioinguinal and iliohypogastric nerves provides better pain control after open repair of inguinal hernia when both blocks were administered under US guidance. Greater satisfaction scores also reflected superior analgesia in patients receiving IINB.

[Effects of propofol sedation on psychological stress in surgical patients under epidural]

OBJECTIVE

To explore the effects of propofol sedation on psychological stress in patients undergoing surgery under epidural anesthesia.

METHODS

Sixty patients scheduled to undergo elective ileostomy closure under epidural anesthesia were randomized into propofol sedation group and control group (n=30). The patients in the sedation group received a loading dose of propofol of 0.6 mg·kg^{- 1}· h^{- 1} followed by a maintenance dose with continuous infusion of 3 mg·kg^{- 1}· h^{- 1} given after the Observer's Assessment of Alertness/Sedation (OAA/S) score reached 2-3. An equivalent volume of normal saline was administered in patients in the control group. The patients' preoperative and intraoperative anxiety scores were assessed with the State Anxiety Inventory (SAI) on the day before and on the first day after the surgery, respectively. The mean blood pressure (MBP), heart rate (HR), SpO₂, OAA/S, and the indicators of psychological stress of brain functional state of the patients (including the wavelet index [WLi], anxiety index [ANXi], comfortable index [CFi] and pain index [Pi]) were recorded at 5 min after entering the operating room (T₀), at the time of lumbar puncture (T₁) and change to supine position after the puncture (T₂), at 20 s (T₃), 40 s (T₄), and 60 s (T₅) after intravenous administration, and at 2 min (T₆), 4 min (T₅), 6 min (T₈), 8 min (T₉), 10 min (T₁₀) and 40 min (T₁₁) after skin incision. The patient's satisfaction with anesthesia was assessed with the Visual Analog Scale (VAS) score on the first day after the operation. Serum cortisol level was measured before anesthesia and at the end of operation to calculate the changes in cortisol level.

RESULTS

The two groups of patients were comparable for preoperative SAI scores (P>0.05); The patients in the sedation group appeared to have lower intraoprative SAI scores, but this difference was not statistically significant (P=0.05). MBP, HR, and SpO₂ at the time points from T₆ to T₁₀ and OAA/S, WLi, ANXi, CFi, and Pi at the time points from T₆ to T₁₁ were significantly lower in the sedation group (all P < 0.05), and these parameters were not significantly different between the two groups at the other time points (all P>0.05). The patient satisfaction scores were significantly higher in the sedation group (Z=2.07, P < 0.05). Compared with the preoperative levels, serum cortisol level at the end of the operation was increased in the sedation group but lowered in the control group, and the variations of serum cortisol level differed significantly between the two groups (t=4.75, P < 0.01).

CONCLUSIONS

Intraoperative propofol sedation can alleviate the patients' anxiety, improve the comfort level, and lessen physiological stress during surgeries under epidural anesthesia.

Remifentanil decreases oral tissue blood flow while maintaining internal carotid artery blood flow during sevoflurane anesthesia in rabbits

The aim of this study was to investigate the effect of remifentanil infusion on oral tissue blood flow including submandibular gland tissue blood flow (SBF) and internal carotid artery blood flow (ICBF) in rabbits during sevoflurane anesthesia. Twelve male Japan White rabbits were anesthetized with sevoflurane and remifentanil. Remifentanil was infused at 0.2 and 0.4 µg/kg/min. Measurements included circulatory variables, common and external carotid artery blood flow (CCBF, ECBF), ICBF, tongue mucosal blood flow (TMBF), masseter muscle tissue blood flow (MBF), mandibular bone marrow tissue blood flow (BBF), tongue muscle tissue blood flow (TBF) and SBF. Vascular resistances for each tissue, including the tongue mucosa, masseter muscle, mandibular bone marrow, tongue muscle and submandibular gland, were calculated by dividing the mean arterial pressure by the respective tissue blood flow. Remifentanil infusion decreased oral tissue blood flow and circulatory variables. CCBF, ECBF and ICBF did not change. The calculated vascular resistance in each oral tissue, except for the tongue mucosa, increased in an infusion-rate-dependent manner. These results showed that remifentanil infusion reduced TMBF, MBF, BBF, TBF and SBF in an infusion-rate-dependent manner without affecting ICBF under sevoflurane anesthesia.

A case series of continuous paravertebral block in minimally invasive cardiac surgery

Background

Minimally invasive cardiac surgery (MICS), via minithoracotomy, is thought to be a fast track to extubation and recovery after surgery. For this, good coverage analgesia is essential. Epidural anesthesia, a standard technique for thoracic surgery, has high risk of complications, such as epidural abscess and spinal hematoma in open-heart surgery. Based on the hypothesis that continuous paravertebral block (CPVB), a less invasive regional anesthetic technique, is safe and effective in open-heart surgery, we applied CPVB to MICS with thoracotomy.

Findings

To assess whether CPVB could be used in open-heart surgery with fewer potential complications, we investigated our medical records of the 87 adult patients who underwent MICS at Akashi Medical Center, Hyogo, Japan, between March 2009 and May 2016. We collected data of CPVB-related complications, postextubation respiratory failure, duration of intubation, and other analgesic use from hospital clinical records. We observed no severe CPVB-related complications, such as hematoma, neuropathy, or abscess. PT-INR longer than 1.1 was associated with CPVB-related minor bleeding. Forty-three patients (47.4%) were extubated within 1 h after surgery, and there were no postextubation respiratory failures in any patients.

Conclusions

We observed no cases of severe CPVB-related complications or postextubation respiratory failure in any of our patients who underwent MICS. Preoperative prolongation of PT-INR was associated with CPVB-related minor bleeding.

Could remifentanil reduce duration of mechanical ventilation in comparison with other opioids for mechanically ventilated patients? A systematic review and meta-analysis

Background

Sedation and analgesia are commonly required to relieve anxiety and pain in mechanically ventilated patients. Fentanyl and morphine are the most frequently used opioids. Remifentanil is a selective μ-opioid receptor that is metabolized by unspecific esterases and eliminated independently of liver or renal function. Remifentanil has a rapid onset and offset and a short context-sensitive half-life regardless of the duration of infusion, which may lead to reductions in weaning and extubation. We aimed to compare the efficacy and safety of remifentanil to that of other opioids in mechanically ventilated patients.

Methods

We conducted a search to identify relevant randomized controlled studies (RCTs) in the PubMed, Embase, Cochrane Library and SinoMed databases that had been published up to 31 December 2016. The results were analysed using weighted mean differences (WMDs) and 95% confidence intervals (CIs).

Results

Twenty-three RCTs with 1905 patients were included. Remifentanil was associated with reductions in the duration of mechanical ventilation (mean difference -1.46; 95% CI -2.44 to -0.49), time to extubation after sedation cessation (mean difference -1.02; 95% CI -1.59 to -0.46), and ICU-LOS (mean difference -0.10; 95% CI -0.16 to -0.03). No significant differences were identified in hospital-LOS (mean difference -0.05; 95% CI -0.25 to 0.15), costs (mean difference -709.71; 95% CI -1590.98 to 171.55; I² 88%), mortality (mean difference -0.64; 95% CI -1.33 to 0.06; I² 87%) or agitation (mean difference -0.71; 95% CI -1.80 to 0.37; I² 93%).

Conclusions

Remifentanil seems to be associated with reductions in the duration of mechanical ventilation, time to extubation after cessation of sedation, and ICU-LOS. No significant differences were identified between remifentanil and other opioids in terms of hospital-LOS, costs, mortality or agitation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1789-8) contains supplementary material, which is available to authorized users.

Fast-track cardiac care for adult cardiac surgical patients

BACKGROUND

Fast-track cardiac care is a complex intervention involving several components of care during cardiac anaesthesia and in the postoperative period, with the ultimate aim of early extubation after surgery, to reduce length of stay in the intensive care unit and in the hospital. Safe and effective fast-track cardiac care may reduce hospital costs. This is an update of a Cochrane review first published in 2003, updated in 2012 and updated now in 2016.

OBJECTIVES

To determine the safety and effectiveness of fast-track cardiac care compared with conventional (not fast-track) care in adult patients undergoing cardiac surgery. Fast-track cardiac care intervention includes administration of low-dose opioid-based general anaesthesia or use of a time-directed extubation protocol, or both.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 5), MEDLINE (January 2012 to May 2015), Embase (January 2012 to May 2015), the Cumulative Index to Nursing and Allied Health Literature (CINAHL; January 2012 to May 2015) and the Institute for Scientific Information (ISI) Web of Science (January 2012 to May 2015), along with reference lists of articles, to identify additional trials. We applied no language restrictions.

SELECTION CRITERIA

We included all randomized controlled trials of adult cardiac surgical patients (coronary artery bypass grafts, aortic valve replacement, mitral valve replacement) that compared fast-track cardiac care and conventional (not fast-track) care groups. We focused on the following fast-track interventions, which were designed for early extubation after surgery: administration of low-dose opioid-based general anaesthesia during cardiac surgery and use of a time-directed extubation protocol after surgery. The primary outcome was risk of mortality. Secondary outcomes included postoperative complications, reintubation within 24 hours of surgery, time to extubation, length of stay in the intensive care unit and in the hospital, quality of life after surgery and hospital costs.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted study data. We contacted study authors for additional information. We calculated a Peto odds ratio (OR) for risk of mortality and used a random-effects model to report risk ratio (RR), mean difference (MD) and 95% confidence intervals (95% CIs) for all secondary outcomes.

MAIN RESULTS

We included 28 trials (4438 participants) in the updated review. We considered most participants to be at low to moderate risk of death after surgery. We assessed two studies as having low risk of bias and 11 studies high risk of bias. Investigators reported no differences in risk of mortality within the first year after surgery between low-dose versus high-dose opioid-based general anaesthesia groups (OR 0.53, 95% CI 0.25 to 1.12; eight trials, 1994 participants, low level of evidence) and between a time-directed extubation protocol versus usual care (OR 0.80, 95% CI 0.45 to 1.45; 10 trials, 1802 participants, low level of evidence).Researchers noted no significant differences between low-dose and high-dose opioid-based anaesthesia groups in the following postoperative complications: myocardial infarction (RR 0.98, 95% CI 0.48 to 1.99; eight trials, 1683 participants, low level of evidence), stroke (RR 1.17, 95% CI 0.36 to 3.78; five trials, 562 participants, low level of evidence) and tracheal reintubation (RR 1.77, 95% CI 0.38 to 8.27; five trials, 594 participants, low level of evidence).Comparisons with usual care revealed no significant differences in the risk of postoperative complications associated with a time-directed extubation protocol: myocardial infarction (RR 0.59, 95% CI 0.27 to 1.31; eight trials, 1378 participants, low level of evidence), stroke (RR 0.85, 95% CI 0.33 to 2.16; 11 trials, 1646 participants, low level of evidence) and tracheal reintubation (RR 1.34, 95% CI 0.74 to 2.41; 12 trials, 1261 participants, low level of evidence).Although levels of heterogeneity were high, low-dose opioid anaesthesia was associated with reduced time to extubation (reduction of 4.3 to 10.5 hours, 14 trials, 2486 participants, low level of evidence) and length of stay in the intensive care unit (reduction of 0.4 to 7.0 hours, 12 trials, 1394 participants, low level of evidence). Use of a time-directed extubation protocol was associated with reduced time to extubation (reduction of 3.7 to 8.8 hours, 16 trials, 2024 participants, low level of evidence) and length of stay in the intensive care unit (reduction of 3.9 to 10.5 hours, 13 trials, 1888 participants, low level of evidence). However, these two fast-track care interventions were not associated with reduced total length of stay in the hospital (low level of evidence).

AUTHORS' CONCLUSIONS

Low-dose opioid-based general anaesthesia and time-directed extubation protocols for fast-track interventions have risks of mortality and major postoperative complications similar to those of conventional (not fast-track) care, and therefore appear to be safe for use in patients considered to be at low to moderate risk. These fast-track interventions reduced time to extubation and shortened length of stay in the intensive care unit but did not reduce length of stay in the hospital.

Remifentanil temporarily improves renal function in adult patients with chronic kidney disease undergoing orthopedic surgery

PURPOSE

The objective of this study was to confirm the renal protective effect of remifentanil-based anesthesia in perioperative adult patients with chronic kidney disease (CKD).

METHODS

A total of 90 non-dialysis perioperative adult patients with CKD, with preoperative estimated glomerular filtration rate from creatinine (eGFRcreat) values of lower than 50 ml/min/1.73 m(2), who had undergone orthopedic surgery under general anesthesia were retrospectively selected. The subjects were divided into two groups according to whether or not remifentanil was used for anesthesia management: group R, in which remifentanil was used for anesthesia management (n = 45), and group NR, in which remifentanil was not used for anesthesia (n = 45). eGFRcreat was measured pre-surgery (pre), 7 days after surgery (day-7), and 14 days after surgery (day-14).

RESULTS

In group R, both day-7 eGFRcreat (52.2 ± 17.0 ml/min/1.73 m(2)) and day-14 eGFRcreat (49.7 ± 15.5 ml/min/1.73 m(2)) were significantly higher than the pre eGFRcreat (40.7 ± 7.5 ml/min/1.73 m(2)) (day-7: p < 0.01; day-14: p < 0.01). In group NR, on the other hand, pre eGFRcreat (37.8 ± 7.6 ml/min/1.73 m(2)), day-7 eGFRcreat (41.2 ± 10.9 ml/min/1.73 m(2)), and day-14 eGFRcreat (40.2 ± 10.5 ml/min/1.73 m(2)) values were similar. Furthermore, both day-7 eGFRcreat and day-14 eGFRcreat were significantly higher in group R than in group NR (day-7: p < 0.01; day-14: p < 0.01).

CONCLUSIONS

Our findings suggest that anesthesia management using remifentanil may have a renal protective effect in perioperative adult CKD patients undergoing orthopedic surgery.

The effect of intraoperative use of high-dose remifentanil on postoperative insulin resistance and muscle protein catabolism: a randomized controlled study

OBJECTIVE

We investigated the effect of the intraoperative use of a high dose remifentanil on insulin resistance and muscle protein catabolism.

DESIGN

Randomized controlled study.

PATIENTS AND INTERVENTION

Thirty-seven patients undergoing elective gastrectomy were randomly assigned to 2 groups that received remifentanil at infusion rates of 0.1 μg·kg(-1)·min(-1) (Group L) and 0.5 μg·kg(-1)·min(-1) (Group H).

MAIN OUTCOME MEASURES

Primary efficacy parameters were changes in homeostasis model assessment as an index of insulin resistance (HOMA-IR) and 3-methylhistidine/creatinine (3-MH/Cr). HOMA-IR was used to evaluate insulin resistance, and 3-MH/Cr was used to evaluate the progress of muscle protein catabolism. Intraoperative stress hormones, insulin, and blood glucose were assessed as secondary endpoints.

RESULTS

Eighteen patients in Group L and 19 in Group H were examined. HOMA-IR values varied within normal limits in both groups during surgery, exceeding normal limits at 12 h after surgery and being significantly elevated in Group L. There were no significant differences in the 3-MH/Cr values between the 2 groups at any time point. The stress hormones (adrenocorticotropic hormone, cortisol, and adrenaline) were significantly elevated in Group L at 60 min after the start of surgery and at the initiation of skin closure. There were no significant differences in insulin values, but blood glucose was significantly elevated in Group L at 60 min after the start of surgery and at the start of skin closure.

CONCLUSION

Use of high-dose remifentanil as intraoperative analgesia during elective gastrectomy reduced postoperative insulin resistance, although it did not reduce postoperative muscle protein catabolism.

Correlation of surgical pleth index with stress hormones during propofol-remifentanil anaesthesia

Eighty patients undergoing elective ear-nose-throat surgery were enrolled in the present study to investigate the relationship between surgical pleth index (SPI) and stress hormones (ACTH, cortisol, epinephrine, norepinephrine) during general anaesthesia which was induced and maintained with propofol and remifentanil using a target-controlled infusion. The study concluded that the SPI had moderate correlation to the stress hormones during general anaesthesia, but no correlation during consciousness. Furthermore, SPI values were able to predict ACTH values with high sensitivity and specificity.

Administration of Remifentanil in Establishing a more Stable Post-anesthesia Cardiovascular Status in Neurosurgical Procedures

INTRODUCTION

Emergence from general anesthesia and especially post-extubation phase are the stages associated with cardiovascular hyperdynamic status in which patients with increased intracranial pressure (ICP) could be affected by severe cardiac and or cerebral complications. Administering remifentanil could be helpful in maintaining the hemodynamic stability at the end of the surgery and recovery stages and reducing recovery phase length.

METHODS

In a double-blind prospective randomized clinical trial, 60 adult patients with ASA (American Society of Anesthesiologist) class of I-II scheduled to undergo elective neurosurgery operations were randomly divided into two groups receiving remifentanil and placebo as IV infusion within four minutes prior to extubation continued by an IV infusion for 10 minutes after extubation.

RESULTS

There was a significant difference between two groups regarding the changes of Mean Arterial Pressure after extubation and five minutes after extubation (P˂ 0.001).Remifentanil group compared with control group was of significant difference at all heart rate values after extubation (P< 0.001).

CONCLUSION

Remifentanil could be used in preventing hyperdynamic status throughout extubation phase without extending recovery phase length. However, administration of this medication should be performed cautiously.

Blood Glucose Control During Selective Arterial Stimulation and Venous Sampling for Localization of Focal Hyperinsulinism Lesions in Anesthetized Children

Surgical management of congenital hyperinsulinism is improved by accurate localization of small, focal dysregulated pancreatic lesions using the arterial stimulation and venous sampling (ASVS) test, which can demonstrate increased hepatic venous insulin concentrations after selective arterial injections of calcium. However, anesthesia-related increases in blood glucose can induce insulin secretion, making it difficult to interpret ASVS test data. In this retrospective study, we examined the effect of anesthetic interventions on blood glucose concentrations in 68 children undergoing ASVS testing. We considered only the glucose concentrations observed before calcium stimulation in the final analysis. The choice of drugs for induction (sevoflurane, propofol, or thiopentone), maintenance inhaled anesthetics (sevoflurane, desflurane, or isoflurane), and the use of caudal epidural bupivacaine were not associated with significant differences in the mean blood glucose concentration before ASVS. However, patients receiving remifentanil infusions had smaller mean glucose concentrations (80 +/- 18 versus 100 +/- 44 mg x dl(-1), P = 0.01). These concentrations were also significantly smaller if tracheal intubation was delayed for at least 10 min after induction while patients received inhaled anesthetics via a face mask along with remifentanil infusions (79 +/- 14 for delayed intubation versus 95 +/- 39 mg x dl(-1) for early intubation, respectively, P = 0.03). The percentage increase in glucose concentrations from preintubation values was significantly smaller in these subjects (3.7% +/- 21.9% for delayed intubation versus 31.7% +/- 60.4% for early intubation, P = 0.02). We conclude that the anesthetic management protocol for these patients should include the use of remifentanil infusions and the administration of inhaled anesthetics and remifentanil infusions for a minimum of 10 min to establish a deep plane of anesthesia before tracheal intubation.