Neuroendocrine stress response in gynecological laparoscopy: TIVA with propofol versus sevoflurane anesthesia

Study ObjectiveTo compare intraoperative and postoperative neuroendocrine stress responses during total intravenous anesthesia (TIVA) using propofol and remifentanil versus sevoflurane anesthesia, during laparoscopic surgery.DesignProspective, randomized study.SettingTertiary-care university hospital.Patients46 ASA physical status I patients undergoing laparoscopic surgery for benign ovarian cysts.InterventionPatients were randomly allocated to two groups to receive either TIVA (Group A = 23) or sevoflurane anesthesia (Group B = 23).MeasurementsPerioperative plasma levels of norepinephrine (NE), epinephrine (E), adrenocorticotropic hormone (ACTH), cortisol, growth hormone (GH), prolactin (PRL), and thyroid hormones (TSH, FT₃, FT₄) were measured. Blood samples were collected preoperatively, 30 minutes after the beginning of surgery, after extubation, and two and 4 hours after the end of surgery (times 0, 1, 2, 3, and 4).Main ResultsIn Group A, perioperative levels of NE, E, ACTH, cortisol, and GH compared with preoperative values significantly decreased; in Group B they increased (Groups A vs. B: time 1, P < 0.001 for all markers; time 2, P < 0.001 for E, ACTH, cortisol, and GH; time 3, P < 0.01 for cortisol, NE, and E, and P < 0.05 for ACTH and GH). Perioperative PRL levels were significantly enhanced in both groups versus preoperative values. In both groups, TSH levels increased while FT₃ levels decreased significantly relative to basal values. In both groups, perioperative FT₄ levels significantly increased compared with preoperative values.ConclusionsTIVA inhibited the ACTH-cortisol axis and reduced NE, E, and GH levels, but it enhanced PRL and had a weak effect on thyroid hormone concentrations as compared to sevoflurane anesthesia.     

Postoperative confusion in schizophrenic patients is affected by interleukin-6

STUDY OBJECTIVE: To investigate whether epidural analgesia with local anesthetics affects postoperative confusion in schizophrenic patients or the relationships between cortisol or interleukin-6 (IL-6) and postoperative confusion. DESIGN: Prospective, randomized study. SETTING: Hakodate Watanabe Hospital and Hirosaki National Hospital. PATIENTS: 105 patients who were scheduled to undergo abdominal surgery with general anesthesia. INTERVENTIONS: The schizophrenic patients were rendomly divided into two groups: patients in Group A received epidural anesthesia and patients in Group B did not receive epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: Postoperative confusion during the first 48 hours after the end of operation occurred in 7 of 33 patients (21%) in Group A and 10 of 33 patients (30%) in Group B. There were no significant differences in the frequency of postoperative confusion between Groups A and B. Plasma cortisol concentrations in schizophrenic patients in Group A were significantly lower 15 minutes after incision and the end of surgery than those levels of patients in Group B; however, there was no significant difference between groups in plasma cortisol concentrations after anesthesia. Plasma IL-6 concentrations (51.7 +/- 22.0 and 31.4 +/- 8.2 pg mL(-1)) in patients with postoperative confusion at the end of surgery and 24 hours after surgery were significantly higher than those levels (34.4 +/- 16.2 and 16.9 +/- 7.7 pg mL(-1)) in patients without postoperative confusion. CONCLUSIONS: Epidural anesthesia does not significantly decrease the frequency of postoperative confusion in schizophrenic patients. Plasma IL-6 concentrations at the end of the operation and 24 hours after surgery in schizophrenic patients with postoperative confusion were significantly higher than those concentrations in patients without postoperative confusion.     

A background infusion of morphine does not enhance postoperative analgesia after cardiac surgery

PURPOSE: To compare the effects of patient-controlled analgesia (PCA), with or without a background infusion of morphine on postoperative pain relief and stress response after cardiac anesthesia. METHODS: With University Ethics approval, 35 consenting adults undergoing elective open-heart surgery were randomly assigned preoperatively in a double-blind fashion to receive either morphine PCA alone (Group I, n = 15) or morphine PCA plus a continuous basal infusion (Group II, n = 14) for 44 hr postoperatively. Pain scores with visual analogue scale (VAS) at rest, deep inspiration and with cough, sedation scores, stress hormone levels [cortisol, adrenocorticotropin (ACTH) and growth hormone (GH)] and morphine consumption were assessed, and serum morphine levels were measured at four, 20, 28 and 44 hr after surgery. Adverse effects including nausea, vomiting, constipation, urinary retention and pruritus were noted. Total blood, fluid requirements, drainage and urinary output were recorded. RESULTS: Postoperative morphine consumption at 44 hr was less in Group I (29.43 +/- 12.57 mg) than in Group II (50.14 +/- 16.44 mg), P = 0.0006. There was no significant difference between groups in VAS scores, GH levels, blood levels of morphine and adverse effects. While VAS scores, ACTH and GH levels decreased significantly in both groups, plasma cortisol levels increased significantly in Group I only at four hours. In Group II, ACTH and cortisol were higher at four and 44 hr respectively. CONCLUSION: PCA with morphine effectively controlled postoperative pain after cardiac surgery. The addition of a background infusion of morphine did not enhance analgesia and increased morphine consumption.     

The effects of sevoflurane and desflurane on lipid peroxidation during laparoscopic cholecystectomy

BACKGROUND AND OBJECTIVE: To compare the effects of sevoflurane and desflurane anaesthesia on lipid peroxidation. METHODS: We studied 40 healthy patients undergoing elective laparoscopic cholecystectomy. Patients were randomly allocated to be anaesthetized either with sevoflurane (n = 20) or desflurane (n = 20). Anaesthesia was maintained with inspiratory concentrations of sevoflurane 1-1.5 MAC (n = 20) or desflurane (n = 20). Samples were taken for plasma malondialdehyde and superoxide dismutase assays before induction of anaesthesia, before skin incision and at the end of surgery. Alveolar cell samples were obtained from the lungs using the technique of protective blind bronchoalveolar lavage, after induction of anaesthesia and at the end of surgery for malondialdehyde and superoxide dismutase concentrations. RESULTS: Plasma malondialdehyde increased more after the administration of desflurane than after sevoflurane: after induction 5.9 +/- 0.6 nmol mL(-1) for desflurane vs. 3.8 +/- 0.5 nmol L(-1) for sevoflurane (P < 0.001); at the end of the surgery: 6.7 +/- 0.4 nmol mL(-1) for desflurane vs. 4.2 +/- 0.3 nmol mL(-1) for sevoflurane (P < 0.001). There was a small but significant increase in plasma superoxide dismutase concentration after desflurane--from 24.2 +/- 1.2 to 24.9 +/- 0.9 U mL(-1) after induction and 25 +/- 1 U mL(-1) at the end of the surgery (P < 0.01)--but no increase with sevoflurane. Malondialdehyde concentrations increased significantly in the cells obtained by protective blind bronchoalveolar lavage at the end of surgery in the desflurane group (from 0.3 +/- 0.1 to 1.7 +/- 0.2 nmol mL(-1) (P < 0.001)), but not in the sevoflurane group. There were no significant differences between the two anaesthetics in the amounts of superoxide dismutase in the samples obtained by protective blind bronchoalveolar lavage. CONCLUSIONS: Desflurane may cause more systemic and regional lipid peroxidation than sevoflurane during laparoscopic cholecystectomy in healthy human beings.     

Perioperative stress response in elderly patients for elective gastrectomy--the comparison between isoflurane anesthesia and sevoflurane anesthesia both combined with epidural anesthesia

The difference in stress responses between isoflurane anesthesia (I group) and sevoflurane anesthesia (S group) was studied. Twelve patients for elective gastrectomy were divided into two groups: S group, 7 patients, 78 +/- 4.3 years of age, and I group, 5 patients, 77.4 +/- 6.9 years of age. Anesthesia was induced by fentanyl, midazolam and sevoflurane or isoflurane with 100% oxygen. After laryngeal mask air way was inserted under spontaneous ventilation, anesthesia was maintained with air (3 l.min-1), oxygen (2 l.min-1), sevoflurane or isoflurane and epidural block. Vecuronium bromide was given during surgery when needed. The demographic data were not different between the two groups. During operation, it was confirmed that the responses of sympathetic nervous system (epinephrine, norepinephrine) and pituitary-adrenocortical system (ACTH, cortisol) were maintained in both groups. After operation plasma norepinephrine levels increased in both groups. Although the responses of I group tended to be stronger than that of S group, there was no significant difference between the two groups.     

Recovery and pharmacokinetic parameters of desflurane, sevoflurane, and isoflurane in patients undergoing urologic procedures.

STUDY OBJECTIVE: To compare the pharmacokinetics and the speed of recovery after inhalation anesthesia with desflurane, sevoflurane, and isoflurane in elective surgery. DESIGN: Prospective, randomized study. SETTING: University medical center. PATIENTS: 30 ASA physical status I and II adults presenting for elective surgery. INTERVENTIONS: Anesthesia was induced with etomidate and maintained with desflurane (n = 10), sevoflurane (n = 10), or isoflurane (n = 10) and nitrous oxide. The inhalation drugs were titrated until an adequate clinical depth of anesthesia was reached. At the end of anesthesia, the patients breathed oxygen via the endotracheal tube and after extubation via a face mask. MEASUREMENTS AND MAIN RESULTS: The groups were similar with respect to age, weight, duration of anesthesia, and mean arterial pressure. Mean end-tidal concentration (FA = FA0) at the end of anesthesia was 6.34 +/- 1.15% after desflurane, 1.85 +/- 0.42% after sevoflurane, and 1.10 +/- 0.24% after isoflurane. FA/FA0 decreased significantly faster with desflurane than with isoflurane, while there was little difference between desflurane and sevoflurane. As for the terminal half-life (t1/2), there were no differences among the groups (8.16 +/- 3.15 min after desflurane, 9.47 +/- 4.46 min after sevoflurane, and 10.0 +/- 5.57 min after isoflurane). The time until a command was followed for the first time was the same in all three groups (13.0 +/- 4.7 min after desflurane, 13.4 +/- 4.4 min after sevoflurane, and 13.6 +/- 3.4 min after isoflurane). There was no significant correlation between duration of anesthesia and the time until recovery. CONCLUSIONS: There are only minor differences with regard to the recovery phase in premedicated patients who receive clinically titrated inhalation anesthesia with desflurane, sevoflurane, or isoflurane.     

Immediate anesthesia recovery and psychomotor function of patient after prolonged anesthesia with desflurane, sevoflurane or isoflurane

OBJECTIVE: To compare the anesthetic maintenance and early postoperative recovery and psychomotor function in patients who have been anesthestized with desflurane, sevoflurane or isoflurane during prolonged open urological surgery. PATIENTS AND METHODS: Seventy-five patients were randomly assigned to receive desflurane, sevoflurane or isoflurane with N2O 60% for anesthetic maintenance. The concentration of each drug was adjusted to maintain arterial pressure and heart rate +/- 20% of baseline. After the operation the anesthetics were discontinued and times until eye opening, spontaneous breathing, extubation and orientation were recorded. In the post-anesthesia recovery ward we applied the Newman-Trieger and Aldrete tests and recorded instances of nausea and vomiting and need for analgesia during the first 24 hours after surgery. RESULTS: The groups were similar with regard to demographic features, anesthetic maintenance, duration of anesthesia and relative doses of the anesthetics used. Recovery times in the operating room were significantly shorter (p < 0.05) after anesthesia with desflurane and sevoflurane than with isoflurane, with no significant differences between the desflurane and sevoflurane groups (duration of anesthesia 198 +/- 90, 171 +/- 67 and 191 +/- 79; eye opening 7.6 +/- 3.7, 7.8 +/- 3.0 and 11.9 +/- 4.5; time until extubation 7.8 +/- 3.0, 8.3 +/- 3.0 and 11.0 +/- 3.5 for desflurane, sevoflurane and isoflurane, respectively; all data in minutes). Recovery in the post-anesthetic recovery ward was similar for all three groups. CONCLUSIONS: Anesthetic maintenance was comparable with all three drugs. Desflurane and sevoflurane demonstrated advantages over isoflurane during recovery from anesthesia in the operating theater. No significant differences were found in psychomotor recovery, nausea and/or vomiting or requirements for postoperative analgesia.     

Preoperative shift from glibenclamide to insulin is cardioprotective in diabetic patients undergoing coronary artery bypass surgery

AIM: The cardioprotective effects afforded by volatile anesthetics, i.e. isoflurane, during heart surgery may be due to preconditioning of the myocardium through the activation of KATP channels. The aims of this study were to establish whether glibenclamide prevents the isoflurane-induced cardioprotection in diabetic patients undergoing coronary surgery (CABG) and whether this cardioprotective effect can be restored by preoperative shift from glibenclamide to insulin therapy. METHODS: We enrolled 60 patients undergoing CABG. Twenty consecutive non-diabetic patients were randomized to receive conventional anesthesia (CA) or conventional anesthesia plus isoflurane (ISO) (added to the inspired oxygen before starting cardiopulmonary bypass); 40 consecutive diabetic patients in chronic treatment with oral glibenclamide were randomized to conventional anesthesia (G-CA), conventional anesthesia plus isoflurane (G-ISO), conventional anesthesia after shifting to insulin (I-CA) or conventional anesthesia plus isoflurane after shifting to insulin (I-ISO). Serum levels of cardiac troponin I (CTnI) and CK-MB, as markers of ischemic injury, were obtained 1, 24, 48 and 96 hours, postoperatively. RESULTS: Postoperative peak levels of CTnI and CK-MB were lower in ISO than in CA (0.5+/-0.3 vs 2.8+/-2.2 ng/ml, p<0.05 and 61+/-27 vs 79+/-28 U/L, p<0.05, respectively), as well as in I-CA and I-ISO than G-CA and G-ISO groups (0.5+/-0.7 and 0.7+/-0.9 vs 3.5+/-3 and 2.7+/-2.5 ng/ml, p<0.05; 47+/-7 and 41+/-5 vs 85+/-28 and 50+/-23 U/L, p<0.05, respectively). No significant differences were detected in postoperative hemodynamic variables or in-hospital outcome. CONCLUSION: This prospective randomized study shows a cardioprotective effect of preoperative administration of isoflurane during CABG. Such an effect is prevented by glibenclamide, but can be restored in diabetic patients by preoperative shift from glibenclamide to insulin.     

Sevoflurane speeds recovery of baroreflex control of heart rate after minor surgical procedures compared with isoflurane.

Volatile anesthetics attenuate arterial baroreflex functions, whereas noxious stimuli may modify baroreflex-induced circulatory responses during anesthesia. We designed the present study to compare baroreflex control of heart rate during sevoflurane and isoflurane anesthesia in young healthy surgical patients. Baroreflex sensitivity was assessed in 24 patients randomized to receive either sevoflurane (n = 12) or isoflurane (n = 12) for general anesthesia. After an 8- to 10-h fast and no premedication, measurements of RR intervals obtained from electrocardiography and systolic blood pressure (SBP) measured through a radial artery catheter were made at conscious baseline (Awake), during end-tidal sevoflurane 2% or isoflurane 1.2% plus 67% nitrous oxide before incision (Anesth), during surgery at end-tidal sevoflurane 2% or isoflurane 1.2% plus 67% nitrous oxide (Surg), and 20 min after tracheal extubation (Recov). Baroreflex responses were triggered by bolus i.v. injections of phenylephrine (100-150 micrograms) and nitroprusside (100-150 micrograms) to increase and decrease SBP by 15-30 mm Hg, respectively. The linear portions of the baroreflex curves relating RR intervals and SBP were determined to obtain baroreflex sensitivities. Baroreflex sensitivities to both pressor and depressor tests were significantly depressed during Anesth and Surg periods compared with Awake values in both anesthetic techniques. The pressor test sensitivity during the Recov period returned to the Awake value after sevoflurane (12.9 +/- 3.7 vs 11.0 +/- 8.7 ms/mm Hg [mean +/- SD]) but was still depressed after isoflurane anesthesia (13.9 +/- 8.0 vs 4.8 +/- 3.2 ms/mm Hg; P < 0.05). The depressor test sensitivities during the Recov period remained depressed after both anesthetic techniques. We conclude that both sevoflurane and isoflurane depress arterial baroreflex function during anesthesia and surgery, but the pressor test sensitivity was restored more quickly after sevoflurane than after isoflurane anesthesia. Implications: Arterial baroreflex function is an important neural control system for maintaining cardiovascular stability. We found that baroreflex control of heart rate due to hypertensive perturbation returned to the preanesthetic level more quickly after sevoflurane than after isoflurane anesthesia.     

Etomidate inhibits adrenocortical function in surgical patients

Postoperative adrenocortical function was compared in 23 out-patients receiving either thiopental, 4 mg/kg, for induction and a thiopental infusion, 0.26 mg . kg-1 . min-1, in combination with nitrous oxide 70% for maintenance of anesthesia (control); etomidate, 0.4 mg/kg, for induction followed by an etomidate infusion, 0.02 mg . kg-1 . min-1, and nitrous oxide 70% for maintenance (etomidate I); or etomidate, 0.4 mg/kg, for induction and a thiopental infusion, 0.22 mg . kg-1 . min-1, in combination with nitrous oxide 70% for maintenance (etomidate II). The norepinephrine response to anesthesia and surgery did not differ significantly between the three groups. The postoperative cortisol response to ACTH stimulation was normal in the control group (maximum rise in plasma cortisol was 20.1 +/- 2.9 micrograms/dl [mean +/- SEM] ), however, it was decreased in all patients receiving etomidate, whether by a short infusion (mean change in plasma cortisol was -3.8 +/- 1.9 micrograms/dl) or as a single induction dose (mean change in plasma cortisol was -4.0 +/- 2.0 micrograms/dl). Similarly, the postoperative aldosterone levels in the control group increased normally in response to ACTH (+ 10.2 +/- 3.0 ng/dl) but decreased in both the etomidate I and etomidate II groups (-3.0 +/- 0.7 ng/dl and -3.3 +/- 1.0 ng/dl, respectively). Because ACTH was administered exogenously, etomidate-induced suppression of adrenocortical response appeared to be a direct effect on the adrenal gland, which was present at a time when the serum etomidate levels were in the subhypnotic range.(ABSTRACT TRUNCATED AT 250 WORDS)     

Stress hormone changes in general anesthesia of long duration: isoflurane-nitrous oxide vs sevoflurane-nitrous oxide anesthesia

STUDY OBJECTIVE: There are few comparative studies of stress hormone changes during general anesthesia with long duration between isoflurane-nitrous oxide and sevoflurane-nitrous oxide anesthesia. We investigated perioperative changes of stress hormone in these two anesthetic methods with duration of more than 10 hours. DESIGN: Prospective study. SETTING: Operating room and high care unit of a university hospital. PATIENTS: Twenty patients with ASA physical status I or II for surgery for laryngeal or pharyngeal cancer with expected duration of more than 10 hours. INTERVENTIONS: Anesthesia was induced with midazolam, thiopental, and vecuronium and was maintained with sevoflurane (sevoflurane group) or isoflurane (isoflurane group) with nitrous oxide 4 L/min in oxygen 2 L/min. MEASUREMENTS AND MAIN RESULTS: Plasma concentrations of epinephrine, norepinephrine, cortisol, adrenocorticotropic hormone, and anti-diuretic hormone (ADH); serum concentrations of glucagon and insulin; and blood glucose concentration were measured before inhalation of anesthetics, after 5 and 10 hours, and at 1, 6, and 12 hours after the end of inhalation. Epinephrine and norepinephrine concentrations increased continuously during and after surgery in the isoflurane group whereas it increased only after surgery in the sevoflurane group. Both concentrations were higher in the isoflurane group during anesthesia. Cortisol increased continuously whereas adrenocorticotropic hormone increased only during surgery. Anti-diuretic hormone increased with its peak during surgery and the isoflurane group had significantly higher values than the sevoflurane group. Glucose increased both during and after surgery, insulin increased only after surgery, and glucagon decreased during surgery in both groups. CONCLUSIONS: In inhalation anesthesia with the duration of more than 10 hours, isoflurane-nitrous oxide and sevoflurane-nitrous oxide had the same effects on stress hormone changes except for epinephrine, norepinephrine, and ADH. Epinephrine, norepinephrine, and ADH concentrations were higher in isoflurane-nitrous oxide anesthesia.     

The effects of prolonged low-flow sevoflurane anesthesia on renal and hepatic function

We assessed the effects of prolonged low-flow sevoflurane anesthesia on renal and hepatic functions by comparing high-flow sevoflurane with low-flow isoflurane anesthesia. Thirty patients scheduled for surgery of > or =10 h in duration randomly received either low-flow (1 L/min) sevoflurane anesthesia (n = 10), high-flow (6-10 L/min) sevoflurane anesthesia (n = 10), or low-flow (1 L/min) isoflurane anesthesia (n = 10). We measured the circuit concentrations of Compound A and serum fluoride. Renal function was assessed by blood urea nitrogen, serum creatinine, creatinine clearance, and urinary excretion of glucose, albumin, protein, and N:-acetyl-beta-D-glucosaminidase. The hepatic function was assessed by serum aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase, and total bilirubin. Compound A exposure was 277 +/- 120 (135-478) ppm-h (mean +/- SD [range]) in the low-flow sevoflurane anesthesia. The maximum concentration of serum fluoride was 53.6 +/- 5.3 (43.4-59.3) micromol/L for the low-flow sevoflurane anesthesia, 47.1 +/- 21.2 (21.4-82.3) micromol/L for the high-flow sevoflurane anesthesia, and 7.4 +/- 3.2 (3.2-14.0) micromol/L for the low-flow isoflurane anesthesia. Blood urea nitrogen and serum creatinine were within the normal range, and creatinine clearance did not decrease throughout the study period in any group. Urinary excretion of glucose, albumin, protein, and N:-acetyl-beta-D-glucosaminidase increased after anesthesia in all groups, but no significant differences were seen among the three groups at any time point after anesthesia. Lactate dehydrogenase and alkaline phosphatase on postanesthesia Day 1 were higher in the high-flow sevoflurane group than in the low-flow sevoflurane group. However, there were no significant differences in any other hepatic function tests among the groups. We conclude that prolonged low-flow sevoflurane anesthesia has the same effect on renal and hepatic functions as high-flow sevoflurane and low-flow isoflurane anesthesia. Implications: During low-flow sevoflurane anesthesia, intake of Compound A reached 277 +/- 120 ppm-h, but the effect on the kidney and the liver was the same in high-flow sevoflurane and low-flow isoflurane anesthesia.     

腹腔镜胆囊切除术中不同麻醉方法对应激反应的影响

目的：观察以丙泊酚、瑞芬太尼为主的全凭静脉麻醉对腹腔镜胆囊切除术（laparoscopic cholecystectomy,LC）患者应激反应的影响。方法：将ASA I-II级需行LC的患者随机分成两组（A组丙泊酚、瑞芬太尼诱导并维持,B组丙泊酚、芬太尼诱导异氟醚吸入维持）,每组30例。记录两组麻醉前（T0）、插管后即刻（T1）、气腹后即刻（T2）、气腹后30min（T3）及术毕（T4）的平均动脉压（MAP）、心率（HR）,于T0、T2、T3及术后2h抽取静脉血检测患者血糖、血浆皮质醇、肾上腺素及去甲肾上腺素浓度。结果：T1和T2A组MAP、HR显著低于B组（P〈0.01）。两组血浆皮质醇、肾上腺素及去甲肾上腺素浓度,T2和T3浓度均明显升高（P〈0.01,P〈0.05）,A组患者上升幅度明显低于B组（P〈0.01,P〈0.05）。血糖于T3至T4两组患者均明显升高（P〈0.01,P〈0.05）,,两组间无明显差别。结论：以丙泊酚和瑞芬太尼为主的全凭静脉麻醉,较以异氟醚和芬太尼为主的传统麻醉用于LC,能够更有效的抑制气管插管和二氧化碳气腹所致的应激反应。     

Emergence agitation in preschool children: double-blind, randomized, controlled trial comparing sevoflurane and isoflurane anesthesia

BACKGROUND: This randomized, double-blind controlled trial was conducted to determine whether the association of sevoflurane for induction and isoflurane for anesthesia maintenance resulted in a lower incidence of postoperative agitation compared with sevoflurane as single agent. METHODS: After Institute Ethics Committee's approval and parental written informed consent, 128 unpremedicated children (1-6 years), ASA I-II, scheduled for elective subumbilical surgery were enrolled. After induction with 8% sevoflurane, patients were randomly allocated to receive sevoflurane or isoflurane 1-1.5 MAC as maintenance agent. The primary endpoint of the study was the incidence of postoperative agitation defined as a screaming and crying child and/or a child that required physical restraint during emergence. RESULTS: Eighteen children were excluded because they received sedatives, analgesia or anesthesia or because of ineffective regional analgesia before randomization. Fifty-four patients receiving sevoflurane and 56 receiving isoflurane completed the study. Twenty-eight children (95% CI 38-66%) in the sevoflurane group presented with postoperative agitation compared with 18 (95% CI 20-46%) patients receiving isoflurane (P = 0.028). Fifteen minutes after awakening, 11/54 children receiving sevoflurane were agitated compared with 4/56 receiving isoflurane (P = 0.03). Thereafter, there was a gradual reduction in the incidence of postoperative agitation over time. CONCLUSIONS: The association of sevoflurane for induction and isoflurane for maintenance produced significant less postoperative agitation in preschool children receiving regional anesthesia during subumbilical surgery compared with sevoflurane for induction and maintenance.     

Comparison of renal function following anesthesia with low-flow sevoflurane and isoflurane.

STUDY OBJECTIVE: To evaluate postoperative renal function after patients were administered sevoflurane under conditions designed to generate high concentrations of compound A. STUDY DESIGN AND SETTING: A multicenter (11 sites), multinational, open-label, randomized, comparative study of perioperative renal function in patients who have received low-flow (< or = 1 L/min) sevoflurane or isoflurane. PATIENTS: 254 ASA physical status I, II and III patients requiring endotracheal intubation for elective surgery lasting more than 2 hours. INTERVENTIONS: After induction, low-flow anesthesia was initiated at a flow rate < or = 1 L/min. Blood and urine samples were studied to assess postoperative renal function. MEASUREMENTS AND MAIN RESULTS: Measurements of serum BUN and creatinine, and urine glucose, protein, pH, and specific gravity were used to assess renal function preoperatively and up to 3 days postoperatively. Serum inorganic fluoride ion concentration was measured at preinduction, emergence, and 2, 24 and 72 hours postoperatively. Compound A concentrations were measured at two sites for those patients receiving sevoflurane. Adverse experience data were analyzed. One hundred eighty-eight patients were considered evaluable (98 sevoflurane and 90 isoflurane). Peak serum fluoride concentrations were significantly higher after sevoflurane (40 +/- 16 microM) than after isoflurane (3 +/- 2 microM). Serum creatinine and BUN decreased in both groups postoperatively; glucosuria and proteinuria occurred in 15% to 25% of patients. There were no clinically significant differences in BUN, creatinine, glucosuria, and proteinuria between the low-flow sevoflurane and low-flow isoflurane patients. CONCLUSIONS: There were no statistically significant differences in the renal effects of sevoflurane or isoflurane in surgical patients undergoing low-flow anesthesia for up to 8 hours. Low-flow sevoflurane anesthesia under clinical conditions expected to produce high levels of compound A appears as safe as low-flow isoflurane anesthesia.     

Local Cerebral Blood Flow, Local Cerebral Glucose Utilization, and Flow-Metabolism Coupling during Sevoflurane versus Isoflurane Anesthesia in Rats

Background: Compared to isoflurane, knowledge of local cerebral glucose utilization (LCGU) and local cerebral blood flow (LCBF) during sevoflurane anesthesia is limited.

Methods: LCGU, LCBF, and their overall means were measured in Sprague-Dawley rats (8 groups, n = 6 each) during sevoflurane and isoflurane anesthesia, 1 and 2 MAC, and in conscious control animals (2 groups, n = 6 each) using the autoradiographic 2-[(14) C]deoxy-D-glucose and 4-iodo-N-methyl-[(14) C]antipyrine methods.

Results: During anesthesia, mean cerebral glucose utilization was decreased: control, 56 +/- 5 [micro sign]mol [middle dot] 100 g-1 [middle dot]-1; 1 MAC isoflurane, 32 +/- 4 [micro sign]mol [middle dot] 100 g-1 [middle dot] min-1 (-43%); 1 MAC sevoflurane, 37 +/- 5 [micro sign]mol [middle dot] 100 g-1 [middle dot] min-1 (-34%); 2 MAC isoflurane, 23 +/- 3 [micro sign]mol [middle dot] 100 g-1 [middle dot] min-1 (-58%); 2 MAC sevoflurane, 23 +/- 5 [micro sign]mol [middle dot] 100 g-1 [middle dot] min-1 (-59%). Local analysis showed a reduction in LCGU in the majority of the 40 brain regions analyzed. Mean cerebral blood flow was increased as follows: control, 93 +/- 8 ml [middle dot] 100 g-1 [middle dot] min-1; 1 MAC isoflurane, 119 +/- 19 ml [middle dot] 100 g-1 [middle dot] min-1 (+28%); 1 MAC sevoflurane, 104 +/- 15 ml [middle dot] 100 g-1 [middle dot] min-1 (+12%); 2 MAC isoflurane, 149 +/- 17 ml [middle dot] 100 g-1 [middle dot] min-1 (+60%); 2 MAC sevoflurane, 118 +/- 21 ml [middle dot] 100 g-1 [middle dot] min-1 (+27%). LCBF was increased in most brain structures investigated. Correlation coefficients obtained for the relationship between LCGU and LCBF were as follows: control, 0.93; 1 MAC isoflurane, 0.89; 2 MAC isoflurane, 0.71; 1 MAC sevoflurane, 0.83; 2 MAC sevoflurane, 0.59).     

Small-dose ketamine improves the postoperative state of depressed patients

We investigated whether ketamine is suitable for depressed patients who had undergone orthopedic surgery. We studied 70 patients with major depression and 25 patients as the control (Group C). The depressed patients were divided randomly into two groups; patients in Group A (n = 35) were induced with propofol, fentanyl, and ketamine and patients in Group B (n = 35) were induced with propofol and fentanyl, and all patients were maintained with 1.5%-2.0% isoflurane plus nitrous oxide. The mean Hamilton Depression Rating (HDR) score was 12.7 +/- 5.4 for Group A and 12.3 +/- 6.0 for Group B 2 days before surgery and 9.9 +/- 4.1 for Group A and 14.4 +/- 3.8 for Group B 1 day after surgery. The HDR score in Group A 1 day after surgery was significantly (P < 0.05) lower than that in Group B. The HDR score in Group C was 4.2 +/- 1.7 2 days before surgery and 4.8 +/- 1.6 1 day after surgery. Depressed mood, suicidal tendencies, somatic anxiety, and hypochondriasis significantly decreased in Group A as compared with Group B. Postoperative pain scores in Group A at 8 and 16 h after the end of anesthesia were 26.6 +/- 8.7 and 24.9 +/- 8.2, respectively, which were significantly (P < 0.05) lower than 34.3 +/- 12.0 and 31.1 +/- 8.8 in Group B. In conclusion, small-dose ketamine improved the postoperative depressive state and relieved postoperative pain in depressed patients. IMPLICATIONS: NMDA receptor antagonists are reported to be effective for improving depression. It remains unclear whether ketamine, which is an NMDA receptor antagonist, postoperatively affects the psychological state in depressed patients. We investigated the effect of 1.0 mg/kg of ketamine on postoperative outcomes in depressed patients.     

Premedication with midazolam delays recovery after ambulatory sevoflurane anesthesia in children.

We studied the effect of oral premedication with midazolam on the recovery characteristics of sevoflurane anesthesia in small children. In a randomized, double-blinded study, 60 children (1-3 yr, ASA physical status I or II) undergoing ambulatory adenoidectomy received either midazolam 0.5 mg/kg (Group M) or placebo (Group P) PO approximately 30 min before the induction of anesthesia. All children received atropine 0.01 mg/kg IV and alfentanil 10 microg/kg IV before the induction of anesthesia with sevoflurane up to 8 vol% inspired concentration in N2O 67% in O2. Tracheal intubation was facilitated with mivacurium 0.2 mg/kg. Anesthesia was continued with sevoflurane adjusted to maintain hemodynamic stability. In the postanesthesia care unit, predetermined recovery end points (emergence, recovery, discharge) were recorded. A pain/ discomfort scale was used to determine the quality of recovery. A postoperative questionnaire was used to evaluate the well-being of the patient at home 24 h after surgery. Emergence (spontaneous eye opening), recovery (full points on the modified Aldrete scale), and discharge were achieved later in Group M than in Group P (15+/-6 vs. 11+/-3 min [P = 0.002], 25+/-17 vs. 16+/-6 min [P = 0.01], and 80+/-23 vs. 70+/-23 min [P = 0.03]). Side effects, postanesthetic excitement, and analgesic treatment did not differ significantly between groups. At home, more children in Group P (30%) experienced disturbed sleep during the night compared with those in Group M (4%) (P = 0.007). IMPLICATIONS: In this randomized, double-blinded, placebo-controlled study, premedication with midazolam 0.5 mg/kg PO delayed recovery in children 1-3 yr of age after brief (<30 min) sevoflurane anesthesia. Except for more peaceful sleep at home, premedication did not affect the quality of recovery.     

The impact of isoflurane, desflurane, or sevoflurane on the frequency and severity of postoperative nausea and vomiting after lumbar disc surgery

STUDY OBJECTIVE: To test the hypothesis that anesthesia with the low-soluble inhalation anesthetics, sevoflurane, and desflurane, may result in a lower frequency and severity of postoperative nausea and vomiting (PONV) than anesthesia with isoflurane. DESIGN: Prospective, observational study. SETTING: Postoperative care unit and neurosurgical ward at a university hospital. PATIENTS: 625 ASA physical status I, II, and III patients undergoing elective lumbar disc surgery with general anesthesia were included in this study. INTERVENTIONS: Patients were enrolled sequentially to receive either 0.7%-1.2% isoflurane (year 2002), 3.5%-5.5% desflurane (year 2003), or 1.2%-1.9% sevoflurane (year 2004) for maintenance of anesthesia without nitrous oxide. Study personnel, general anesthesia management, and surgical technique remained unchanged over the three-year study period. MEASUREMENTS: Occurrence of PONV within 24 hours of the end of surgery was recorded. Secondary outcome measures were occurrence of multiple PONV episodes, maximum severity, time to the first PONV event, need for rescue medication, difference between the occurrence of PONV (indicator variable) and the expected risk of PONV (based on the Apfel score). MAIN RESULTS: Type of inhalation anesthetic had no influence on PONV frequency (9.3%, 11.2%, and 10.8% after isoflurane, desflurane, and sevoflurane, respectively; P = 0.8) or its severity (numerical rating scale, 4.5 +/- 2.0, 4.4 +/- 2.4, and 4.2 +/- 2.1; P = 0.9). Patients who received isoflurane experienced fewer early events but had a late peak of PONV frequency (P = 0.031). For every 10 minutes by which the total duration of the anesthesia exceeded the net time between incision and suture, the risk of PONV increased by a factor of 1.36 (95% confidence interval, 1.15-1.61; P < 0.001). CONCLUSIONS: There is no difference between the three inhalation anesthetics currently used with regard to frequency or severity of postoperative nausea, vomiting, or both.     

Ketorolac is not nephrotoxic in connection with sevoflurane anesthesia in patients undergoing breast surgery

Ketorolac, which may cause renal vasoconstriction by cyclooxygenase inhibition, is often administered to patients anesthetized with sevoflurane that is metabolized to inorganic fluoride (F(-)), another potential nephrotoxin. We assessed this possible interaction using urine N-acetyl-beta-D-glucosaminidase indexed to urinary creatinine (U-NAG/crea) as a marker of proximal tubular, beta2-microglobulin as a tubular, urine oxygen tension (P(u)O(2)) as a medullary, and erythropoietin as a marker of tubulointerstitial damage. Thirty women (ASA physical status I-II) undergoing breast surgery were included in our double-blinded study. They were allocated into two groups receiving either ketorolac 30 mg IM (Group K) or saline (Group C) at the time of premedication, at the end of, and 6 h after anesthesia maintained with sevoflurane. Urine output, U-NAG/crea, P(u)O(2,) serum creatinine, urea, and F(-) were assessed. Blood loss was larger in Group K (465 +/- 286 mL vs 240 +/- 149 mL, mean +/- SD, P < 0.05). The MAC-doses of sevoflurane were similar. U-NAG/crea increased during the first 2 h of anesthesia and serum F(-) peaked 2 h after the anesthesia without differences between the groups. There were no statistically significant changes in P(u)O(2), erythropoietin, beta2-microglobulin, serum creatinine, urea, or urine output during anesthesia or the recovery period in either group. Our results indicate that the kidneys are not affected by ketorolac administered in connection with sevoflurane anesthesia. IMPLICATIONS: The different kinetics of N-acetyl-beta-D-glucosaminidase indexed to urinary creatinine and serum inorganic fluoride during and after sevoflurane anesthesia suggest that the observed mild renal tubular function deterioration is not caused by inorganic fluoride. Administration of ketorolac IM is therefore considered safe in adequately hydrated healthy adult patients given sevoflurane anesthesia.