Sevoflurane exerts brain-protective effects against sepsis-associated encephalopathy and memory impairment through caspase 3/9 and Bax/Bcl signaling pathway in a rat model of sepsis.

Objective We compared the effects of sevoflurane and isoflurane on systemic inflammation, sepsis-associated encephalopathy, and memory impairment in a rat sepsis model of cecal ligation and puncture (CLP)-induced polymicrobial peritonitis. Methods Twenty-four rats were assigned to sham, CLP, CLP + sevoflurane, and CLP + isoflurane groups. At 72 hours after CLP, the rats underwent behavior tests. Serum cytokines were evaluated. Brain tissue samples were collected for determination of glutathione peroxidase (GPX), superoxide dismutase (SOD), and catalase; the wet/dry weight ratio; myeloperoxidase (MPO) and malondialdehyde (MDA); apoptotic gene release; and histologic examinations. Results The MPO level, wet/dry weight ratio, and histopathology scores were lower and the Bcl2a1 and Bcl2l2 expressions were upregulated in both the CLP + sevoflurane and CLP + isoflurane groups compared with the CLP group. The interleukin-6, interleukin-1ß, MDA, and caspase 3, 8, and 9 levels were lower; the GPX, SOD, Bax, Bcl2, and Bclx levels were higher; and non-associative and aversive memory were improved in the CLP + sevoflurane group compared with the CLP + isoflurane group. Conclusion Sevoflurane decreased apoptosis and oxidative injury and improved memory in this experimental rat model of CLP. Sevoflurane sedation may protect against brain injury and memory impairment in septic patients.

The effect of regional block over pain levels during vacuum-assisted wound closure.

Despite being a wound treatment method with a broad spectrum of indications, vacuum-assisted wound closure (VAWC) can be a painful treatment modality which may even result with patient unwillingness for the continuation of treatment. A prospective study was undertaken to determine the effect of regional pain blocks (RPB) for patients who wanted to abandon treatment due to pain after the first application. Patients were asked to score their pain using a visual analogue scale for two different time frames (i) during dressing changes and (ii) while daytime treatment. This evaluation was carried out for conventional wound dressings, VAWC before RPB and finally for VAWC after RPB. The pain experienced with blocks was significantly lesser than conventional and VAWC dressing changes that were applied without pain blocks. Also, the pain was significantly lesser under pain blocks for daytime treatment. For patients with refractory pain where VAWC would prove to be of most benefit, RPB can be discussed with the patient and used. This study has shown that effective pain control can be obtained through regional blocks for patients with excruciating pain undergoing VAWC treatment.

Sevoflurane and isoflurane preconditioning provides neuroprotection by inhibition of apoptosis-related mRNA expression in a rat model of focal cerebral ischemia.

BACKGROUND: This study aimed to examine the effects of sevoflurane or isoflurane preconditioning on cerebral ischemia/reperfusion-induced inflammation, oxidative stress, and lipid peroxidation and test the hypothesis that the underlining mechanism of the protective effect of preconditioning involves changes in the apoptotic gene expression profiles in an experimental model of middle cerebral artery occlusion in rats. METHODS: Twenty-four adult male rats were randomly divided into 3 groups: control (n=8), sevoflurane (n=8), and isoflurane (n=8). For preconditioning, these 3 groups were exposed to 40% O2, 2% sevoflurane, and 1.5% isoflurane, respectively, for 60 minutes, followed immediately by 1 hour of middle cerebral artery occlusion and then 6 hours of reperfusion. Blood and brain tissue samples were collected for determination of blood gas tension, tumor necrosis factor-α, interleukin-6, and interleukin-1ß. Brain tissue samples were collected for determination of the wet/dry ratio, myeloperoxidase, malondialdehyde, and total RNA and also for histologic examinations. RESULTS: Tumor necrosis factor-α, interleukin-1ß, and myeloperoxidase levels decreased and antioxidant enzyme levels increased in the sevoflurane group compared with the control and isoflurane groups. Proapoptotic genes (Tnf, Tnfrsf10b, and Tp53) downregulated and antiapoptotic genes (Aven, Bcl2, Bcl2l2, and Prok2) upregulated with sevoflurane treatment compared with the isoflurane and control groups. Both isoflurane and sevoflurane pretreatment decreased malondialdehyde, Dffb, the wet/dry ratio, and injury score and upregulated Bax and Apaf 1 compared with the control group. CONCLUSIONS: Sevoflurane and isoflurane preconditioning ameliorates inflammation, cerebral lipid peroxidation, and histologic injury. Downregulation of proapoptotic molecules and upregulation of antiapoptotic molecules may be associated with this effect.

Do we need bispectral index monitoring during total intravenous anesthesia for lumbar discectomies?

The aim of this study was to investigate the effect of bispectral index (BIS) monitoring on hemodynamic parameters, drug consumption and awareness during total intravenous anesthesia (TIVA) with remifentanil and propofol in lumbar discectomies. After institutional ethical committee approval, ASAI-II 56 patients were divided as control and BIS groups. Anesthesia was induced by bolus remifentanil 1 mug/kg in both groups; propofol 2 mg/kg in was used in the control group while propofol was titrated to BIS 45- 65 values in the BIS group. Anesthesia was maintained by remifentanil and propofol infusions. Drug consumption, time to extubation and awareness were recorded. Demographic parameters were similar between the groups. Consumption of propofol was lower, and time to extubation was shorter in the BIS group; there was no difference between awareness among groups. BIS monitoring was helpful for propofol titration and decreased propofol consumption, but not enough to prevent reaction to noxious stimuli. Standard anesthesia titration considering hemodynamic parameters was enough for most ASA I-II patients for lumbar discectomies. BIS might be more helpful for patients who cannot show hemodynamic responses to noxious stimuli. More studies are needed to investigate the correlation between positioning and awareness using BIS monitoring.

Magnesium sulphate as an adjuvant to total intravenous anesthesia in septorhinoplasty: a randomized controlled study.

BACKGROUND: The current study was designed to assess the effect of magnesium sulphate infusion on hemodynamic parameters, neuromuscular blocking, propofol consumption, serum concentration of magnesium ions, and recovery from anesthesia during total intravenous anesthesia. METHODS: For this study, 60 patients undergoing septorhinoplasty operations were randomly allocated to receive magnesium sulphate (group M) or saline (group C) intravenously. The patients in group M received 15% magnesium sulphate 50 mg/kg in 100 ml of saline, and those in group C received an equal volume of saline before induction of anesthesia followed by 8 mg/kg/h infusion of either magnesium sulphate (group M) or an equal volume of saline (group C) until the end of surgery. Anesthesia was induced and maintained with propofol, remifentanil infusions, and vecuronium in both groups. RESULTS: Propofol requirements were significantly lower in group M than in group C (p < 0.05). The hemodynamic variables were similar in the two groups. The neuromuscular potency of vecuronium was greater in group M than in group C (p < 0.05). The verbal numeric scale values for pain were found to be significantly lower in group M than in group C (p < 0.05). Whereas the serum magnesium was in the normal range at the induction of anesthesia in the both groups, it was significantly lower in group C than in group M postoperatively (p < 0.05). CONCLUSION: Magnesium sulphate can be used safely as an adjuvant to total intravenous anesthesia for day case surgeries, with the effect from potentialization of neuromuscular blockade taken into consideration.

Successful use of levosimendan in a patient during cardiopulmonary bypass.

Levosimendan (LS) is a novel calcium sensitizer drug that enhances cardiac contractility without increasing myocardial oxygen consumption, and induces vasodilatation. Positive inotropic support is routinely used for weaning from cardiopulmonary bypass circulation in patients with reduced left ventricular function. This case report represents the successful usage of LS for weaning from cardiopulmonary bypass circulation after coronary artery bypass surgery. Levosimendan infusion was started at the sixth hour of cardiopulmonary bypass circulation. There was a dramatic increase in cardiac output 20 minutes after LS infusion, and weaning from cardiopulmonary bypass circulation was achieved. We suggest that LS enhances cardiac performance during and after cardiopulmonary bypass, and can be useful for patients who are unable to be weaned from cardiopulmonary bypass.

Hemodynamic effects, recovery profiles, and costs of remifentanil-based anesthesia with propofol or desflurane for septorhinoplasty.

OBJECTIVE: To compare hemodynamics, recovery profiles, postoperative side effects and costs of desflurane-remifentanil and propofol-remifentanil anesthesia for septorhinoplasty operations. METHODS: A prospective and randomized study was carried out at the Gazi University Hospital, Ankara, Turkey from April to September 2003. Forty patients undergoing septorhinoplasty operations were randomly allocated to receive desflurane-remifentanil (Group DES-REM) or total intravenous anesthesia (TIVA) (Group TIVA). Anesthesia was induced in both groups with remifentanil 1 microg x ml (-1), propofol 2-2.5 mg.kg-1 and pancuronium 0.1 mg.kg-1. Maintenance was achieved with O2 50% in air at 4 L.min-1 and infusion of remifentanil 0.1 microg x ml (-1).min-1 in both groups. Group DES-REM received desflurane at 1 minimum alveolar concentration and Group TIVA received 10-4 mg.kg-1.hour-1 of propofol. Propofol infusion and desflurane were discontinued with the last surgical stitches, but remifentanil infusion continued in both groups until the nose was covered with plaster. Hemodynamic variables were recorded during the operation and one hour postoperatively in 5 min intervals. We recorded time of extubation, spontaneous eye opening and response to verbal commands times, visual analog scale pain scores, postoperative nausea and vomiting and Aldrete Recovery Score. Drug dosages and costs of each technique were determined. RESULTS: There were no statistically significant differences between the groups with respect to hemodynamic parameters, recovery profile, adverse effects, Aldrete Recovery Score and cost analysis. Visual analog scale at 5 min postoperatively was higher in group desflurane-remifentanil compared to group propofol-remifentanil (p<0.05). CONCLUSION: Both desflurane-remifentanil and TIVA provide perioperative hemodynamic stability, early and easy recovery with similar cost profiles for septorhinoplasty operations.

Hemodynamic and anesthetic advantages of dexmedetomidine, an alpha 2-agonist, for surgery in prone position.

The alpha2-agonist dexmedetomidine (Dex), a sedative and analgesic, reduces heart rate (HR) and blood pressure, and has been used in the practice of anesthesia. In this study, we aimed to evaluate the effects of Dex on hemodynamic variables, anesthetic sparing effects, and recovery profiles in patients who underwent surgery in prone position. The prone position itself can cause a decrease in the systemic blood pressure. Forty patients who undergo lumbar discectomy were randomly assigned to receive either Dex (a loading dose 1 microg/ kg in 10 minutes followed by an infusion rate of 0.2 microg/ kg/ hr) or saline. In both groups, the anesthesia was induced with fentanyl, thiopental and rocuronium, and maintained with desflurane in 50% N(2)O. Mean arterial blood pressure (MAP), HR, cardiac output (CO), and level of anesthesia were monitored. Recovery times and analgesic requirements were also recorded. As a response to endotracheal intubation, a significant increase in MAP and HR was observed in the control group compared to the Dex group, but no difference in CO. The recovery times were significantly shorter in the Dex group compared to the control group. Anesthetic and analgesic requirements of the Dex group were lower than controls. Thus, the use of Dex caused no detrimental effects on the hemodynamic variables in prone position. In addition, Dex decreased pressure response to intubation, and anesthetic and analgesic requirements, shortened recovery times, and decreased postoperative pain level. Dex may be an alternative to currently used adjunctive anesthetic agents in lumbar discectomy operations.

A different intracardiac mass: retained sponge.

We report a case involving a surgical sponge retained following an aortic valve replacement. The surgical sponge was placed into the left ventricle to protect calcified debris from falling down into the left ventricular cavity. However, the sponge was forgotten and left inside the patient. We identified the retained surgical sponge by transesophageal echocardiography, which was performed because of a difficulty in weaning the patient from the cardiopulmonary bypass.

Epidural air entrapment after spinal surgery.

A case which had developed neurological complication because of compression due to air trapping in the epidural space after spinal surgery is presented with its clinical and radiological findings. Nitrous oxide can easily diffuse into the air-filled spaces in the body from the bloodstream and also increases the pressure of the air in the closed spaces. After the L4-5 discectomy procedure, weakness in dorsal flexion was occurred on the contra lateral leg. The patient was evaluated urgently with radiological examinations. Postoperative radiological findings showed air compression between L3 and L5 levels which occupied the epidural space. The surgical approach was not considered. Following the resolution of the air in the epidural space, neurological deficit was progressively improved. In order to prevent neurologic complication due to air trapping in spinal surgery, avoidance of using nitrous oxide and also irrigation of the surgical field with isotonic fluid is recommended.

Radiological and histopathological examination of early tissue reactions to absorbable hemostatic agents in the rabbit brain.

Topical hemostatic agents are widely and safely used in neurosurgery. The purpose of this study was to compare and analyse the early tissue reactions to two hemostatic agents, oxidized regenerated cellulose and gelatin sponge, in rabbit brain by magnetic resonance imaging and histopathologic sections. Bilateral identical parenchymal lesions were made in the frontal regions of each hemisphere in 13 rabbits. Hemostasis was achieved using oxidized regenerated cellulose or gelatin sponge, one agent being used on each side. Cranial magnetic resonance imaging was performed 24 h postoperatively and there was no statistical difference in edema formation at the site of the lesions. Histopathologic examinations indicated that pericapillary edema and endothelial distortion were common in both groups but that there was additional tissue degeneration evident in the regions where gelatin sponge had been used. Oxidized regenerated cellulose seemed to cause greater tissue distortion in magnetic resonance images than gelatin sponge but in contrast, histological examination of lesions in which oxidized regenerated cellulose had been used revealed less tissue degeneration than histopathologic examinations of lesions in which gelatin sponge had been used.

Hemodynamic effects of perioperative stressor events during rhinoplasty.

The hemodynamic effects of perioperative stressors, including preoperative patient anxiety, intraoperative local anesthetic/adrenaline infiltrations, and some painful interventions, have not been fully elucidated in plastic surgery procedures. The present study was designed to determine the hemodynamic effects of perioperative stressor events in American Society of Anesthesiologists class I patients undergoing rhinoplasty procedures under general anesthesia. The study included 50 healthy patients, 18 to 51 years of age (mean age, 27 +/- 7 years), who underwent a rhinoplasty procedure in the authors' department. All patients were connected to a digital ambulatory Holter recorder for 24 hours starting on the day before the operation and continuing throughout the procedure. All of the patients received 10 ml of 2% lidocaine with 1:80,000 adrenaline 15 minutes after intubation. Observations consisted of heart rate, noninvasive blood pressure, and power spectral heart rate variability analyses, the latter of which is indicative of the sympathovagal balance of the patients. The majority of patients developed a persistent, moderate sinus tachycardia before the induction of anesthesia. After the infiltration of lidocaine/adrenaline, a mild to moderate and short-lasting tachycardia was detected. A similar increase in pulse rate was also noticed during lateral osteotomies. No significant blood pressure changes attributable to perioperative stressors (with the exclusion of general anesthesia induction, intubation, and extubation) were observed. Sympathetic activity was found to be responsible from marked tachycardia before the induction, which was attributable to preoperative anxiety. The authors' study has demonstrated that there are three hemodynamically unstable periods causing tachycardia for rhinoplasty patients that directly concern the plastic surgeon: immediate preoperative anxiety, local anesthetic/adrenaline injection, and lateral osteotomies. The authors conclude that these patients would benefit from routine use of premedications and that a lidocaine/adrenaline combination is a safe adjunct to general anesthesia in young rhinoplasty patients. In addition, a deeper anesthesia during local infiltration and osteotomies would be appropriate.

Intravenous patient-controlled analgesia using remifentanil in a child with Axenfeld-Rieger syndrome.

Patient-controlled analgesia (PCA) using intravenous opioids is increasing in popularity for children aged 5 years and over. To our knowledge there are no reports on the use of PCA in children with remifentanil in the postoperative period. We report successful use of remifentanil for intravenous (IV) PCA in a child scheduled for suprasellar arachnoid cystectomy with Axenfeld-Rieger syndrome who needed good postoperative analgesia because of accompanying serious problems.

Tapia's syndrome following septorhinoplasty.

No surgery is free of complications varying from common minor problems to very unexpected and severe ones. In the case presented here, unilateral paralysis of the muscles of the tongue and ipsilateral vocal cord paralysis due to a lesion of the 10th and 12th cranial nerves occurred following a septorhinoplasty that was performed under endotracheal general anesthesia. This rare entity known as Tapia's Syndrome is believed to be caused by pressure neuropathy of both nerves due to inflation of the cuff within the larynx. We remind surgeons of this unusual complication that can occur in any surgery under general anesthesia and discuss its diagnosis, treatment method, and the followup results in light of the literature.

Comparison of hemodynamics, recovery profile, and early postoperative pain control and costs of remifentanil versus alfentanil-based total intravenous anesthesia (TIVA).

STUDY OBJECTIVE: To compare hemodynamics, recovery profiles, early postoperative pain control and costs of total intravenous anesthesia (TIVA) with propofol and remifentanil and propofol and alfentanil. DESIGN: Randomized, double-blind study. SETTING: University hospital. PATIENTS: 40 ASA physical status I and II adult patients scheduled for lumbar discectomy. INTERVENTIONS: Patients were randomly assigned to receive either remifentanil-propofol or alfentanil-propofol. Anesthesia was induced with remifentanil 1 microg kg(-1) or alfentanil 20 microg kg(-1) with propofol 2 mg kg(-1), and maintained with infusions of propofol 150 to 100 microg kg(-1)min(-1) and either remifentanil 0.1 microg kg(-1) min(-1) or alfentanil 0.5 microg kg(-1) min(-1). MEASUREMENTS: Hemodynamic parameters (heart rate and mean arterial pressure), times to awakening, and tracheal extubation were recorded. In the postanesthesia care unit, pain level, frequency of analgesic demand, frequency of postoperative nausea and vomiting (PONV), partial oxygen saturation (SpO2), and respiratory rates were noted. Drug dosages and costs of each technique were determined. MAIN RESULTS: The mean arterial pressure significantly decreased compared to baseline values 1 minute after induction (p < 0.05) in both groups, and it significantly decreased at 5, 15, and 30 minutes perioperatively in the remifentanil group compared to the alfentanil group (p < 0.05). Time of extubation, spontaneous eye opening, and response to verbal command were similar in both groups. Visual analog scale pain scores at 30 minutes and 60 minutes were significantly lower in the alfentanil group than remifentanil group (p < 0.05). At 15, 30, and 60 minutes after terminating the operation oxygen saturation and respiratory rate were significantly higher (p < 0.05) and analgesics were required sooner in the remifentanil group than the alfentanil group (p < 0.05). The frequency of PONV was similar in both groups. The remifentanil-propofol anesthesia was found to be slightly more expensive as compared to the alfentanil based TIVA (33.41 +/- 4.53 vs. 29.97 +/- 4.1 USD) (p < 0.05). CONCLUSIONS: Both remifentanil and alfentanil provided a reasonably rapid and reliable recovery. The remifentanil-based TIVA was associated with high intraoperative cost and early postoperative pain, but it allowed a more rapid respiratory recovery.