Effect of Dexmedetomidine on Sevoflurane Requirements and Emergence Agitation in Children Undergoing Ambulatory Surgery

Purpose

Dexmedetomidine, a potent selective α2-adrenergic agonist, produces sedation and analgesia. This study was conducted to assess the effect of dexmedetomidine infusion on sevoflurane requirements, recovery profiles, and emergence agitation in children undergoing ambulatory surgery.

Materials and Methods

Forty children undergoing ambulatory hernioplasty or orchiopexy were randomized into two groups. The dexmedetomidine group (Group D, n=20) received dexmedetomidine 1 µg/kg, followed by 0.1 µg/kg/h until the end of surgery, whereas the saline group (Group S, n=20) received volume-matched normal saline. Sevoflurane was used for induction and maintenance of anesthesia and caudal block was performed in all children. End-tidal sevoflurane concentration (ET-sevo), the incidence of emergence agitation, pain scores, and sedation scores were recorded. Hemodynamic changes and other adverse effects were assessed in the perioperative period.

Results

ET-sevo of Group D was significantly reduced in 23.8-67% compared to Group S during surgery. The incidence of emergence agitation was lower in Group D than in Group S (5% vs. 55%, p=0.001). Postoperative pain was comparable, and discharge time was not different between the groups. Mean arterial pressure and heart rate were significantly lower in Group D during surgery.

Conclusion

Intraoperative infusion of dexmedetomidine reduced sevoflurane requirements and decreased emergence agitation without delaying discharge in children undergoing ambulatory surgery. However, caution should be taken in regard to bradycardia and hypotension.     

Beneficial effects of adding ketamine to intravenous patient-controlled analgesia with fentanyl after the Nuss procedure in pediatric patients

Purpose

The aim of this prospective, double-blind, randomized study was to investigate the analgesic effects of low-dose ketamine on intravenous patient-controlled analgesia (IV-PCA) with fentanyl for pain control in pediatric patients following the Nuss procedure for pectus excavatum.

Materials and Methods

Sixty pediatric patients undergoing the Nuss procedure were randomly assigned to receive fentanyl (Group F, n=30) or fentanyl plus ketamine (Group FK, n=30). Ten minutes before the end of surgery, following the loading dose of each solution, 0.5 µg/kg/hr of fentanyl or 0.5 µg/kg/hr of fentanyl plus 0.15 mg/kg/hr of ketamine was infused via an IV-PCA pump (basal rate, 1 mL/hr; bolus, 0.5 mL; lock out interval, 30 min). Fentanyl consumption, pain score, ketorolac use, nausea/vomiting, ondansetron use, pruritus, respiratory depression, hallucination, dreaming, and parent satisfaction with pain control were measured throughout the 48 hours following surgery.

Results

The pain scores, ketorolac use, and fentanyl consumption of Group FK were significantly lower than in Group F (p<0.05). The incidence of nausea/vomiting and ondansetron use in Group FK was significantly lower than in Group F (p<0.05). There were no reports of respiratory depression, hallucination or dreaming. Parent satisfaction with pain control was similar between the two groups.

Conclusion

We concluded that low-dose ketamine added to IV-PCA with fentanyl after the Nuss procedure in pediatric patients can reduce pain scores, consumption of fentanyl, and incidence of nausea/vomiting without increasing side effects.     

Duration effect of desflurane anesthesia and its awakening time and arterial concentration in gynecologic patients

OBJECTIVES:

To determine the awakening arterial blood concentration of desflurane and its relationship with the end-tidal concentration during emergence from various durations of general anesthesia.

METHOD:

In total, 42 American Society of Anesthesiologists physical status class I-II female patients undergoing elective gynecologic surgery were enrolled. General anesthesia was maintained with fixed 6% inspiratory desflurane in 6 l min^-1 oxygen until shutoff of the vaporizer at the end of surgery. One milliliter of arterial blood was obtained for desflurane concentration determination by gas chromatography at 20 and 10 minutes before and 0, 5, 10, 15, and 20 minutes after the discontinuation of desflurane and at the time of eye opening upon verbal command, defined as awakening. Concentrations of inspiratory and end-tidal desflurane were simultaneously detected by an infrared analyzer.

RESULTS:

The mean arterial blood concentration of desflurane was 1.20% at awakening, which correlated with the awakening end-tidal concentration of 0.96%. The mean time from the discontinuation of desflurane to eye opening was 5.2 minutes (SD = 1.6, range 3-10), which was not associated with the duration of anesthesia (60-256 minutes), total fentanyl dose, or body mass index (BMI).

CONCLUSIONS:

The mean awakening arterial blood concentration of desflurane was 1.20%. The time to awakening was independent of anesthetic duration within four hours. Using well-assisted ventilation, the end-tidal concentration of desflurane was proven to represent the arterial blood concentration during elimination and could be a clinically feasible predictor of emergence from general anesthesia.     

Parent-reported symptoms of attention deficit hyperactivity disorder in children with intermittent exotropia before and after strabismus surgery

Purpose

To investigate the symptoms of attention deficit hyperactivity disorder (ADHD) as reported by parents in children with intermittent exotropia [X(T)] and to determine whether strabismus surgery for X(T) affects ADHD symptoms.

Materials and Methods

Fifty-one consecutive children undergoing muscle surgery for X(T) were prospectively recruited. One parent of each child completed the ADHD rating scale IV (ADHD RS-IV) assessment consecutively before and one year after surgery. Patients whose preoperative scores were above the cut-off point, the 90th percentile based on a Korean sample, were regarded as demonstrating the ADHD trait. The impact of muscle surgery on ADHD symptoms was assessed by comparing the preoperative scores with the post-operative scores.

Results

Eight (15.7%) of the 51 patients demonstrated the ADHD trait. ADHD RS-IV scores following strabismus surgery significantly decreased in patients with the ADHD trait (p=0.014), while they did not differ in patients without the ADHD trait. Seven (87.5%) of the 8 patients with the ADHD trait showed improvement in their ADHD RS-IV scores after surgery. There was no difference in surgical success rates between X(T) patients with and without the ADHD trait.

Conclusion

The ADHD trait was relatively common in children with X(T), and the parent-reported symptoms of the children with the ADHD trait improved after strabismus surgery. These results suggest that childhood X(T) may be one contributing factor to ADHD-related symptoms.     

Induction of anesthesia in coronary artery bypass graft surgery: the hemodynamic and analgesic effects of ketamine

OBJECTIVE

The aim of this prospective, randomized study was to evaluate the hemodynamic and analgesic effects of ketamine by comparing it with propofol starting at the induction of anesthesia until the end of sternotomy in patients undergoing coronary artery bypass grafting surgery.

INTRODUCTION

Anesthetic induction and maintenance may induce myocardial ischemia in patients with coronary artery disease. A primary goal in the anesthesia of patients undergoing coronary artery bypass grafting surgery is both the attenuation of sympathetic responses to noxious stimuli and the prevention of hypotension.

METHODS

Thirty patients undergoing coronary artery bypass grafting surgery were randomized to receive either ketamine 2 mg.kg⁻¹ (Group K) or propofol 0.5 mg.kg⁻¹ (Group P) during induction of anesthesia. Patients also received standardized doses of midazolam, fentanyl, and rocuronium in the induction sequence. The duration of anesthesia from induction to skin incision and sternotomy, as well as the supplemental doses of fentanyl and sevoflurane, were recorded. Heart rate, mean arterial pressure, central venous pressure, pulmonary arterial pressure, pulmonary capillary wedge pressure, cardiac index, systemic and pulmonary vascular resistance indices, stroke work index, and left and right ventricular stroke work indices were obtained before induction of anesthesia; one minute after induction; one, three, five, and ten minutes after intubation; one minute after skin incision; and at one minute after sternotomy.

RESULTS

There were significant changes in the measured and calculated hemodynamic variables when compared to their values before induction. One minute after induction, mean arterial pressure and the systemic vascular resistance index decreased significantly in group P (p<0.01).

CONCLUSION

There were no differences between groups in the consumption of sevoflurane or in the use of additional fentanyl. The combination of ketamine, midazolam, and fentanyl for the induction of anesthesia provided better hemodynamic stability during induction and until the end of sternotomy in patients undergoing coronary artery bypass grafting surgery.     

The efficiency of a sedative or analgesic supplement to periprostatic nerve blockage for pain control during transrectal ultrasound-guided prostate biopsy – a prospective,randomized, controlled,double blind study

Introduction

The aim was to examine the effect of a sedative or analgesic supplement to periprostatic nerve blockage (PNB) on pain reduction during probe insertion and needle penetration in patients undergoing transrectal ultrasound (TRUS)-guided prostate biopsy. We also investigated the effects of this procedure on the positive response rate in re-biopsy.

Material and methods

One hundred TRUS-guided prostate biopsy patients due to prostate-specific antigen (PSA) levels higher than 2.5 ng/ml and/or abnormal rectal examination findings were evaluated. Group 1 (PNB) was given periprostatic lidocaine injection before the procedure. Group 2 (analgesic) was given tramadol and PNB. Group 3 (sedative) was given midazolam and PNB. Group 4 (control) was not given any anaesthesia or analgesics. Pain scores were assessed during probe insertion and needle penetration by a visual analogue scale.

Results

During probe insertion, the mean pain score of the sedative group was lower than that of the control, analgesic and PNB groups (p < 0.001, p = 0.009, and p < 0.001, respectively). During needle penetration, the mean pain score of the control group was higher than that of the other groups (p < 0.001). The rate of positive response to re-biopsy was found to be 56% in the control group and between 92% and 100% in the other three groups (p < 0.001).

Conclusion

According to our results, it can be concluded that midazolam, given supplementary to PNB, contributes as an effective and safe alternative for pain control during both probe insertion and penetration of the biopsy needle into the prostate capsule; however, tramadol supplement does not provide any additional contributions.     

Incidence and Risk Factors of Postoperative Nausea and Vomiting in Patients with Fentanyl-Based Intravenous Patient-Controlled Analgesia and Single Antiemetic Prophylaxis

Purpose

We evaluated the incidence and risk factors of postoperative nausea and vomiting (PONV) in patients with fentanyl-based intravenous patient-controlled analgesia (IV-PCA) and single antiemetic prophylaxis of 5-hydroxytryptamine type 3 (5 HT₃)-receptor antagonist after the general anesthesia.

Materials and Methods

In this retrospective study, incidence and risk factors for PONV were evaluated with fentanyl IV-PCA during postoperative 48 hours after various surgeries.

Results

Four hundred-forty patients (23%) of 1878 had showed PONV. PCA was discontinued temporarily in 268 patients (14%), mostly due to PONV (88% of 268 patients). In multivariate analysis, female, non-smoker, history of motion sickness or PONV, long duration of anesthesia (>180 min), use of desflurane and intraoperative remifentanil infusion were independent risk factors for PONV. If one, two, three, four, five, or six of these risk factors were present, the incidences of PONV were 18%, 19%, 22%, 31%, 42%, or 50%. Laparoscopic surgery and higher dose of fentanyl were not risk factors for PONV.

Conclusion

Despite antiemetic prophylaxis with 5 HT₃-receptor antagonist, 23% of patients with fentanyl-based IV-PCA after general anesthesia showed PONV. Long duration of anesthesia and use of desflurane were identified as risk factors, in addition to risk factors of Apfel''s score (female, non-smoker, history of motion sickness or PONV). Also, intraoperative remifentanil infusion was risk factor independent of postoperative opioid use. As the incidence of PONV was up to 50% according to the number of risk factors, risk-adapted, multimodal or combination therapy should be applied.     

Effect of the perioperative infusion of dexmedetomidine on chronic pain after breast surgery

Background:

This prospective double-blind trial was undertaken to analyze the role of perioperatively administered dexmedetomidine on the occurrence of chronic pain in cases undergoing surgery for breast cancer.

Subjects and Methods:

Eighty-six cases were randomly assigned to two groups to receive either dexmedetomidine (2 μg/ml) in group D or saline in group C, in a loading dose of 0.5 ml/kg, intravenous (IV), 30 min prior to induction, followed by a continuous infusion of 0.25 ml/kg/h IV till the completion of surgery, and then the dose tapered to 0.1 ml/kg/h for up to 24 h. The standardized questionnaires that measured chronic pain (Brief Pain Inventory, BPI; Short Form McGill Pain Questionnaire, SF-MPQ2) and quality of life (Quality of Life Scale, QOLS) were gathered after 3 months of surgery as a primary outcome. Pain (verbal numerical score, VNS), sedation scores (Ramsay scoring), and analgesic requirements were also assessed for 72 h postoperatively.

Results:

In total, 84 cases (n=42) were analyzed for acute pain and 69 (34 in group D and 35 in group C) for chronic pain. The consumption of isoflurane/fentanyl intra-operatively and paracetamol postoperatively was significantly lower in Group D. The sedation scores were non-significant between the groups. The VNS at rest and after movement was significantly lower in group D at corresponding times (except at 60 min) throughout the assessment period. The BPI and SF-MPQ2 scores were significantly lower in group D in most of the factors. The QOLS score was significantly better in group D in all items except for relationships, friends, and learning.

Conclusion:

The perioperative infusion of dexmedetomidine has a pivotal role in attenuating the incidence and severity of chronic pain and improving the quality of life in cases undergoing breast cancer surgery.     

Comparison of clonidine and dexmedetomidine for short-term sedation of intensive care unit patients

Background and Objectives:

Patients on mechanical ventilation in intensive care unit (ICU) are often uncomfortable because of anxiety, pain, and endotracheal intubation; therefore, require sedation. Alpha-2 agonists are known to produce sedation. We compared clonidine and dexmedetomidine as sole agents for sedation.

Study Design:

Prospective, randomized, controlled open-label study.

Materials and Methods:

A total of 70 patients requiring a minimum of 12 h of mechanical ventilation with concomitant sedation, were randomly allocated into two groups. Group C (n = 35) received intravenous (IV) clonidine (1 μg/kg/h titrated up to 2 μg/kg/h to attain target sedation), and Group D (n = 35) received IV dexmedetomidine for sedation (loading 0.7 μg/kg and maintenance 0.2 μg/kg/h titrated up to 0.7 μg/kg/h to achieve target sedation). A Ramsay Sedation Score of 3-4 was considered as target sedation. Additional sedation with diazepam was given when required to achieve target sedation. The quality of sedation, hemodynamic changes and adverse effects were noted and compared between the two groups.

Results:

Target sedation was achieved in 86% observations in Group D and 62% in Group C (P = 0.04). Additional sedation was needed by more patients in Group C compared with Group D (14 and 8 in Groups C and D, respectively, P = 0.034), mainly due to concomitant hypotension on increasing the dose of clonidine. Hypotension was the most common side-effect in Group C, occurring in 11/35 patients of Group C and 3/35 patients of Group D (P = 0.02). Rebound hypertension was seen in four patients receiving clonidine, but none in receiving dexmedetomidine.

Conclusion:

Both clonidine and dexmedetomidine produced effective sedation; however, the hemodynamic stability provided by dexmedetomidine gives it an edge over clonidine for short-term sedation of ICU patients.     

Comparison of the effects of propofol and midazolam on inflammation and oxidase stress in children with congenital heart disease undergoing cardiac surgery

Purpose

To investigate and compare the effects of propofol and midazolam on inflammation and oxidase stress in children with congenital heart disease undergoing cardiac surgery.

Materials and Methods

Thirty-two ASA class I-II children with congenital heart disease undergoing cardiac surgery were randomly divided into two groups: propofol combined with low dose fentanyl (PF group, n = 16) and midazolam combined with low dose fentanyl (MF group, n = 16). Tracheal extubation time and length of Intensive Care Unit (ICU) stay were recorded. Blood samples were taken before operation (T₀), at 2 h after release of the aorta cross-clamp (T₃) and at 24 h after operation (T₄) to measure interleukin 6 (IL-6), IL-8, superoxide dismutase (SOD) and malondialdehyde (MDA) levels. Myocardium samples were collected at 10-20 min after aorta cross-clamp (T₁) and at 10-20 min after the release of the aorta cross-clamp (T₂) to detect heme oxygenase-1 (HO-1) expression.

Results

Tracheal extubation time and length of ICU stay in PF group were significantly shorter than those of the MF group (p < 0.05, respectively). After cardiopulmonary bypass, IL-6, IL-8 and MDA levels were significantly increased, and the SOD level was significantly reduced in both two groups, but PF group exhibited lower IL-6, IL-8 and MDA levels and higher SOD levels than the MF group (p < 0.05, respectively). The HO-1 expression in the PF group was significantly higher than that in MF group at the corresponding time points (p < 0.05, respectively).

Conclusion

Propofol is superior to midazolam in reducing inflammation and oxidase stress and in improving post-operation recovery in children with congenital heart disease undergoing cardiac surgery.     

Coronary Flow Reserve in the Remote Myocardium Predicts Left Ventricular Remodeling Following Acute Myocardial Infarction

Purpose

Coronary flow reserve (CFR) in the non-infarcted myocardium is often impaired following acute myocardial infarction (AMI). However, the clinical significance of CFR in the non-infarcted myocardium is not fully understood. The objective of the present study was to assess whether a relationship exists between CFR and left ventricular remodeling following AMI.

Materials and Methods

We enrolled 18 consecutive patients undergoing coronary intervention. Heart function was analyzed using real-time myocardial contrast echocardiography at one week and six months after coronary angioplasty. Ten subjects were enrolled as the control group and were examined using the same method at the same time to assess CFR. Cardiac troponin I (cTnI) levels were routinely analyzed to estimate peak concentration.

Results

CFR was 1.55±0.11 in the infarcted zone and 2.05±0.31 in the remote zone (p<0.01) at one week following AMI. According to CFR values in the remote zone, all patients were divided into two groups: Group I (CFR <2.05) and Group II (CFR >2.05). The levels of cTnI were higher in Group I compared to Group II on admission (36.40 vs. 21.38, p<0.05). Furthermore, left ventricular end diastolic volume was higher in Group I compared to Group II at six months following coronary angioplasty.

Conclusion

Microvascular dysfunction is commonly observed in the remote myocardium. The CFR value accurately predicts adverse ventricular remodeling following AMI.     

Effect of Dexmedetomidine on the Corrected QT and Tp-e Intervals during Spinal Anesthesia

Purpose

The aim of this study is to evaluate the effect of dexmedetomidine on corrected QT (QTc) and Tp-e intervals in patients undergoing spinal anesthesia.

Materials and Methods

We studied 50 patients who were scheduled to undergo spinal anesthesia before orthopedic surgeries. Patients were allocated to receive either an infusion of dexmedetomidine or normal saline after spinal anesthesia.

Results

QTc intervals were significantly prolonged after spinal anesthesia, and the prolonged QTc interval returned to baseline values 10 minutes after either normal saline or dexmedetomidine administration in both groups. The QTc interval values after dexmedetomidine administration were significantly shorter compared to the QTc interval values just before dexmedetomidine administration.

Conclusion

Dexmedetomidine could promote the return of a prolonged QTc interval induced by spinal anesthesia and might be helpful in patients who have a prolonged QTc interval.     

Pulse pressure variation and stroke volume variation under different inhaled concentrations of isoflurane,sevoflurane and desflurane in pigs undergoing hemorrhage

OBJECTIVES:

Inhalant anesthesia induces dose-dependent cardiovascular depression, but whether fluid responsiveness is differentially influenced by the inhalant agent and plasma volemia remains unknown. The aim of this study was to compare the effects of isoflurane, sevoflurane and desflurane on pulse pressure variation and stroke volume variation in pigs undergoing hemorrhage.

METHODS:

Twenty-five pigs were randomly anesthetized with isoflurane, sevoflurane or desflurane. Hemodynamic and echocardiographic data were registered sequentially at minimum alveolar concentrations of 1.00 (M1), 1.25 (M2), and 1.00 (M3). Then, following withdrawal of 30% of the estimated blood volume, these data were registered at a minimum alveolar concentrations of 1.00 (M4) and 1.25 (M5).

RESULTS:

The minimum alveolar concentration increase from 1.00 to 1.25 (M2) decreased the cardiac index and increased the central venous pressure, but only modest changes in mean arterial pressure, pulse pressure variation and stroke volume variation were observed in all groups from M1 to M2. A significant decrease in mean arterial pressure was only observed with desflurane. Following blood loss (M4), pulse pressure variation, stroke volume variation and central venous pressure increased (p<0.001) and mean arterial pressure decreased in all groups. Under hypovolemia, the cardiac index decreased with the increase of anesthesia depth in a similar manner in all groups.

CONCLUSION:

The effects of desflurane, sevoflurane and isoflurane on pulse pressure variation and stroke volume variation were not different during normovolemia or hypovolemia.     

Perioperative Psychological and Music Interventions in Elderly Patients Undergoing Spinal Anesthesia: Effect on Anxiety,Heart Rate Variability,and Postoperative Pain

Purpose

The aim of this study was to evaluate the effects of perioperative psychological and music interventions in elderly patients undergoing elective surgery on anxiety, post-operative pain, and changes in heart rate variability (HRV) to ascertain if perioperative psychological and music interventions can affect overall anxiety levels.

Materials and Methods

Fourty elderly patients undergoing elective surgery were randomized to two groups; one group received psychological and music intervention, and the other was the control. The intervention group underwent psychological intervention and listening to music for 30 min before surgery.

Results

The mean change in HRV as determined by low frequency (LF) power measurements. After the intervention, the ratio of mean LF to high frequency (HF) power decreased significantly in the intervention group compared to before the intervention (p<0.05). In the control group, mean LF measurements and the ratio of LF:HF did not change significantly. In the intervention group, mean HF power was significantly higher after the procedure than before (p<0.01). Moreover, the mean self-rating anxiety score of the intervention group decreased after the procedure compared to before (p<0.05). The mean visual analogue score of the intervention group 6 hours after surgery was significantly lower than that of the control group (p<0.01).

Conclusion

Perioperative psychological and music interventions can reduce anxiety and postoperative pain in elderly patients.     

Ultrasonographic scoring system score versus liver stiffness measurement in prediction of cirrhosis

Background/Aims

We compared the cirrhosis-prediction accuracy of an ultrasonographic scoring system (USSS) combining six representative sonographic indices with that of liver stiffness measurement (LSM) by transient elastography, and prospectively investigated the correlation between the USSS score and LSM in predicting cirrhosis.

Methods

Two hundred and thirty patients with chronic liver diseases (187 men, 43 women; age, 50.4±9.5 y, mean±SD) were enrolled in this prospective study. The USSS produces a combined score for nodularity of the liver surface and edge, parenchyma echogenicity, presence of right-lobe atrophy, spleen size, splenic vein diameter, and abnormality of the hepatic vein waveform. The correlations of the USSS score and LSM with that of a pathological liver biopsy (METAVIR scoring system: F0-F4) were evaluated.

Results

The mean USSS score and LSM were 7.2 and 38.0 kPa, respectively, in patients with histologically overt cirrhosis (F4, P=0.017) and 4.3 and 22.1 kPa in patients with fibrotic change without overt cirrhosis (F0-F3) (P=0.025). The areas under the receiver operating characteristic (ROC) curves of the USSS score and LSM for F4 patients were 0.849 and 0.729, respectively. On the basis of ROC curves, criteria of USSS ≥6: LSM ≥17.4 had a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 89.2%:77.6%, 69.4%:61.4%, 86.5%:83.7%, 74.6%:51.9% and 0.83:0.73, respectively, in predicting F4.

Conclusions

The results indicate that this USSS has comparable efficacy to LSM in the diagnosis of cirrhosis.     

Neurobehavioral Performance in Young Adults Living on a 28-h Day for 6 Weeks

Objectives:

Performance on many cognitive tasks varies with time awake and with circadian phase, and the forced desynchrony (FD) protocol can be used to separate these influences on performance. Some performance tasks show practice effects, whereas the Psychomotor Vigilance Task (PVT) has been reported not to show such effects. We aimed to compare performance on the PVT and on an addition test (ADD) across a 6-week FD study, to determine whether practice effects were present and to analyze the circadian and wake-dependent modulation of the 2 measures.

Design and Setting:

A 47-day FD study conducted at the Brigham and Women''s Hospital General Clinical Research Center.

Participants:

Eleven healthy adults (mean age: 24.4 years, 2 women).

Measurements and Results:

For 2 baseline days and across 6 weeks of FD, we gave a test battery (ADD, PVT, self-rating of effort and performance) every 2 hours. During FD, there was a significant (P < 0.0001) improvement in ADD performance (more correct calculations completed), whereas PVT performance (mean reaction time, fastest 10% reaction times, lapses) significantly (P < 0.0001) declined week by week. Subjective ratings of PVT performance indicated that subjects felt their performance improved across the study (P < 0.0001), but their rating of whether they could have performed better with greater effort did not change across the study (P > 0.05).

Conclusions:

The decline in PVT performance suggests a cumulative effect of sleep loss across the 6-week study. Subjects did not accurately detect their declining PVT performance, and a motivational factor could not explain this decline.

Citation:

Lee JH; Wang W; Silva EJ; Chang AM; Scheuermaier KD; Cain SW; Duffy JF. Neurobehavioral performance in young adults living on a 28-h day for 6 weeks. SLEEP 2009;32(7):905-913.     

Kidney Function in Living Donors Undergoing Nephrectomy by Sevoflurane or Desflurane Anesthesia

Purpose

Although there is no clinical evidence of nephrotoxicity with the volatile anesthetics currently used in general anesthesia, a better agent should be needed in terms of preserving postoperative renal function in living kidney donors who have only single remaining kidney. The purpose of the current retrospective, single-center study was to evaluate and compare renal function of living kidney donors after nephrectomy under either sevoflurane or desflurane anesthesia.

Materials and Methods

From January 2006 through December 2011, a total of 228 donors undergoing video assisted minilaparotomy surgery nephrectomy for kidney donation were retrospectively enrolled in the current study. The donors were categorized into a sevoflurane group or desflurane group based on the type of volatile anesthetic used. We collected laboratory data from the patients preoperatively, immediately after the operation, on the first postoperative day and on the third postoperative day. We also compared renal function of the kidney donors after donor nephrectomy by comparing creatinine level and estimated glomerular filtration rate (eGFR).

Results

The decrease in renal function after surgery in both groups was the most prominent on the first postoperative day. There were no significant differences between the two groups in postoperative changes of creatinine or eGFR.

Conclusion

Sevoflurane and desflurane can be used safely as volatile anesthetics in donors undergoing nephrectomy.     

Comparative study of fentanyl and morphine in addition to hyperbaric or isobaric bupivacaine in combined spinal anaesthesia for caesarean section

Introduction

The aim of our study was to compare the effects of isobaric and hyperbaric bupivacaine combined with morphine or fentanyl in patients undergoing caesarean section. We assessed quality and spread of analgesia and anaesthesia, postoperative analgesic requirement and side effects.

Material and methods

Hundred patients with American Society of Anesthesiologists physical status (ASA) I-II, age 18 to 40 years, were randomized to 4 groups. The intrathecal solutions were isobaric bupivacaine + morphine (group A), isobaric bupivacaine + fentanyl (group B), heavy bupivacaine + + morphine (group C) and heavy bupivacaine + fentanyl (group D). Mean arterial pressure, heart rate, oxygen saturation, ephedrine consumption, analgesic requirement time and additional analgesic needs were recorded.

Results

The 1^st min value of mean arterial pressure was the lowest one in all groups. Heart rate decreased significantly in group A at the 10^th min but not in the other groups. The decrease of visual analogue scale (VAS) pain scores began in the groups after the 4^th postoperative h (p < 0.05) and the VAS value of group B at the 8^th h was significantly higher than the other groups. The first analgesic requirement time in the postoperative period was longer in patients who had intrathecal morphine than those who had fentanyl. The duration of analgesia with isobaric bupivacaine and morphine was the longest one.

Conclusions

We concluded that intrathecal morphine provides a long duration of postoperative analgesia but the duration gets longer when it is combined with plain bupivacaine instead of heavy bupivacaine.     

The Effects of Oral Atenolol or Enalapril Premedication on Blood Loss and Hypotensive Anesthesia in Orthognathic Surgery

Purpose

The aim of this study was to evaluate the effects of premedication with oral atenolol or enalapril, in combination with remifentanil under sevoflurane anesthesia, on intraoperative blood loss by achieving adequate deliberate hypotension (DH) during orthognathic surgery. Furthermore, we investigated the impact thereof on the amount of nitroglycerin (NTG) administered as an adjuvant agent.

Materials and Methods

Seventy-three patients undergoing orthognathic surgery were randomly allocated into one of three groups: an angiotensin converting enzyme inhibitor group (Group A, n=24) with enalapril 10 mg, a β blocker group (Group B, n=24) with atenolol 25 mg, or a control group (Group C, n=25) with placebo. All patients were premedicated orally 1 h before the induction of anesthesia. NTG was the only adjuvant agent used to achieve DH when mean arterial blood pressure (MAP) was not controlled, despite the administration of the maximum remifentanil dose (0.3 µg kg^-1min^-1) with sevoflurane.

Results

Seventy-two patients completed the study. Blood loss was significantly reduced in Group A, compared to Group C (adjusted p=0.045). Over the target range of MAP percentage during DH was significantly higher in Group C than in Groups A and B (adjusted p-values=0.007 and 0.006, respectively). The total amount of NTG administered was significantly less in Group A than Group C (adjusted p=0.015).

Conclusion

Premedication with enalapril (10 mg) combined with remifentanil under sevoflurane anesthesia attenuated blood loss and achieved satisfactory DH during orthognathic surgery. Furthermore, the amount of NTG was reduced during the surgery.