Brazilian Journal of Anesthesiology (Edicion en Espanol)最新文献

Background and objectives

Postoperative analgesia is crucial for early functional excise after total knee arthroplasty. To investigate the clinical efficacy of ultrasound and nerve stimulator guided continuous femoral nerve block analgesia after total knee arthroplasty.

Methods

46 patients with ASA grade I-III who underwent total knee arthroplasty received postoperative analgesia from October 2012 to January 2013. In 22 patients, ultrasound and nerve stimulator guided continuous femoral nerve block were performed for analgesia (CFNB group); in 24 patients, epidural analgesia was done (PCEA group). The analgesic effects, side effects, articular recovery and complications were compared between 2 groups.

Results

At 6 h and 12 h after surgery, the knee pain score (VAS score) during functional tests after active exercise and after passive excise in CFNB were significantly reduced when compared with PCEA group. The amount of parecoxib used in CFNB patients was significantly reduced when compared with PCEA group. At 48 h after surgery, the muscle strength grade in CFNB group was significantly higher, and the time to ambulatory activity was shorter than those in PCEA group. The incidence of nausea and vomiting in CFNB patients was significantly reduced when compared with PCEA group.

Conclusion

Ultrasound and nerve stimulator guided continuous femoral nerve block provide better analgesia at 6 h and 12 h, demonstrated by RVAS and PVAS. The amount of parecoxib also reduces, the incidence of nausea and vomiting decreased, the influence on muscle strength is compromised and patients can perform ambulatory activity under this condition.

Background and objectives

In this study, we investigated the anesthetic and mucosal effects of the rectal application of dexmedetomidine to rats.

Methods

Male Wistar albino rats weighing 250–300 g were divided into four groups: group S (n = 8) was a sham group that served as a baseline for the normal basal values; Group C (n = 8) consisted of rats that received the rectal application of saline alone; group IPDex (n = 8) included rats that received the intraperitoneal application of dexmedetomidine (100 μg/kg⁻¹); and group RecDex (n = 8) included rats that received the rectal application of dexmedetomidine (100 μg/kg⁻¹). For the rectal drug administration, we used 22 G intravenous cannulas with the stylets removed. We administered the drugs by advancing the cannula 1 cm into the rectum, and the rectal administration volume was 1 mL for all the rats. The latency and anesthesia time (min) were measured. Two hours after rectal administration, 75 mg/kg⁻¹ ketamine was administered for intraperitoneal anesthesia in all the groups, followed by the removal of the rats’ rectums to a distal distance of 3 cm via an abdominoperineal surgical procedure. We histopathologically examined and scored the rectums.

Results

Anesthesia was achieved in all the rats in the group RecDex following the administration of dexmedetomidine. The onset of anesthesia in the group RecDex was significantly later and of a shorter duration than in the group IPDEx (P < .05). In the Group RecDex, the administration of dexmedetomidine induced mild–moderate losses of mucosal architecture in the colon and rectum, 2 h after rectal inoculation.

Conclusion

Although 100 μg/kg⁻¹ dexmedetomidine administered rectally to rats achieved a significantly longer duration of anesthesia compared with the rectal administration of saline, our histopathological evaluations showed that the rectal administration of 100 μg/kg⁻¹ dexmedetomidine led to mild–moderate damage to the mucosal structure of the rectum.

Background and objectives

Desflurane and sevoflurane are frequently used for maintenance of anesthesia and studies have shown that these anesthetics cause a variety of changes to the oxidative stress and antioxidative defense mechanisms. This study aims to compare the effects of sevoflurane, desflurane and propofol infusion anesthesia on the oxidant and antioxidant systems of patients undergoing laparoscopic cholecystectomy.

Methods

45 patients between 18 and 50 years with planned laparoscopic cholecystectomy under general anesthetic were included in the study. Patients were divided into three groups on the way to surgery: propofol (group P n: 15), sevoflurane (group S n: 15) and desflurane (group D n: 15). All groups were given hypnotic 2 mg/kg propofol iv, 1 μg/kg fentanyl iv and 0.1 mg/kg vecuronium iv for induction. For maintenance of anesthesia group S were ventilated with 2% sevoflurane, group D cases were given 6% desflurane and group P were given propofol infusions of 12 mg/kg/h for the first 10 min, 9 mg/kg/h for the second 10 min, and 6 mg/kg/h after that. Before induction and after the operation venous blood samples were taken to evaluate the levels of glutation peroxidase, total oxidants and antioxidants.

Results and conclusions

The 45 patients included in the study were 22 male and 23 female patients. The demographic characteristics of the groups were similar. In the postoperative period we observed that while sevoflurane and propofol increased antioxidants by a statistically significant level, desflurane increased the total oxidants level by a significant amount compared to levels before the operation.

Background

The purpose of the study was to compare the neurotoxic effects of intrathecally administered levobupivacaine, fentanyl and their mixture on rat spinal cord.

Methods

In experiment, there were 4 groups with medication and a control group. Rats were injected 15 μL saline or fentanyl 0.0005 μg/15 μL, levobupivacaine 0.25%/15 μL and fentanyl 0.0005 μg + levobupivacaine 0.25%/15 μL intrathecally for four days. Hot plate test was performed to assess neurologic function after each injection at 5th, 30th and 60th min. Five days after last lumbal injection, spinal cord sections between the T5 and T6 vertebral levels were obtained for histologic analysis. A score based on subjective assessment of number of eosinophilic neurons –red neuron– which means irreversible neuronal degeneration. They reflect the approximate number of degenerating neurons present in the affected neuroanatomic areas as follows: 1, none; 2, 1–20%; 3, 21–40%; 4, 41–60%; and 5, 61–100% dead neurons. An overall neuropathologic score was calculated for each rat by summating the pathologic scores for all spinal cord areas examined.

Results

In the results of hot plate test, comparing the control group, analgesic latency statistically prolonged for all 4 groups.

In neuropathologic investment, the fentanyl and fentanyl + levobupivacaine groups have statistically significant high degenerative neuron counts than control and saline groups.

Conclusions

These results suggest that, when administered intrathecally in rats, fentanyl and levobupivacaine behave similar for analgesic action, but fentanyl may be neurotoxic for spinal cord. There was no significant degeneration with levobupivacaine, but fentanyl group has had significant degeneration.

Background and objectives

In this study, we aimed to investigate the effects of sevoflurane, desflurane and propofol maintenances on serum levels of selenium, copper, zinc, iron, malondialdehyde, and glutathion peroxidase measurements, and antioxidant capacity.

Methods

60 patients scheduled for unilateral lower extremity surgery which would be performed with tourniquet under general anesthesia were divided into three groups. Blood samples were collected to determine the baseline serum levels of selenium, copper, zinc, iron, malondialdehyde and glutathion peroxidase. Anesthesia was induced using 2-2.5 mg/kg⁻¹ propofol, 1 mg/kg⁻¹ lidocaine and 0.6 mg/kg⁻¹ rocuronium. In the maintenance of anesthesia, under carrier gas of 50:50% O₂:N₂O 4 L/min⁻¹, 1 MAC sevoflorane was administered to group S and 1 MAC desflurane to group D; and under carrier gas of 50:50% O₂:air 4 L/min⁻¹ 6 mg/kg/h⁻¹ propofol and 1 μg/kg/h⁻¹ fentanyl infusion were administered to group P. At postoperative blood specimens were collected again.

Results

It was observed that only in group S and P, levels of malondialdehyde decreased at postoperative 48th hour; levels of glutathion peroxidase increased in comparison to the baseline values. Selenium levels decreased in group S and group P, zinc levels decreased in group P, and iron levels decreased in all three groups, and copper levels did not change in any groups in the postoperative period.

Conclusion

According to the markers of malondialdehyde and glutathion peroxidase, it was concluded that maintenance of general anesthesia using propofol and sevoflurane activated the antioxidant system against oxidative stress and using desflurane had no effects on oxidative stress and antioxidant system.

Background and objectives

Patients’ knowledge deficits concerning anesthesia and the anesthesiologist's role in their care may contribute to anxiety. The objective of this study was to develop anesthesia patient education materials that would help improve patient's satisfaction regarding their knowledge of the perioperative process and decrease anxiety in a community hospital with a large Spanish-speaking population.

Methods

A survey (survey A) in English and Spanish was administered to all adult anesthesiology preoperative clinic patients during a 4-week period. The data were analyzed and then a patient education handout was developed in both English and Spanish to assist with our patients’ major concerns. A second survey (survey B) was administered that was completed after the education handout had been put into use at the clinic. The survey asked for basic demographic information and included questions on satisfaction with regard to understanding of anesthesia as well as worries regarding surgery and pain.

Results

In the patients who received the handout, statistically significant improvement was found in the questions that asked about satisfaction with regard to understanding of type of anesthesia, options for pain control, what patients are supposed to do on the day of surgery, and the amount of information given with regard to anesthetic plan. There was no difference in anxiety related to surgery in patients who received the educational handout compared to those patients who did not.

Conclusions

Patient education handouts improved patient's satisfaction regarding their knowledge of the perioperative process but did not reduce anxiety related to surgery.

Background and objectives

Changes in ocular perfusion play an important role in the pathogenesis of ischemic optic neuropathy. Ocular perfusion pressure is equal to mean arterial pressure minus intraocular pressure. The aim of this study was to evaluate the changes in the intraocular pressure and the retinal nerve fiber layer thickness in patients undergoing spinal surgery in the prone position.

Methods

This prospective study included 30 patients undergoing spinal surgery. Retinal nerve fiber layer thickness were measured one day before and after the surgery by using optical coherence tomography. Intraocular pressure was measured by tonopen six times at different position and time-duration: supine position (baseline); 10 min after intubation (supine 1); 10 min (prone 1), 60 min (prone 2), 120 min (prone 3) after prone position; and just after postoperative supine position (supine 2).

Results

Our study involved 10 male and 20 female patients with the median age of 57 years. When postoperative retinal nerve fiber layer thickness measurements were compared with preoperative values, a statistically significant thinning was observed in inferior and nasal quadrants (P = .009 and P = .003, respectively). We observed a statistically significant intraocular pressure decrease in Supine 1 and an increase in both Prone 2 and Prone 3 when compared to the baseline. Mean arterial pressure and ocular perfusion pressure were found to be significantly lower in prone 1, prone 2 and prone 3, when compared with the baseline.

Conclusions

Our study has shown increase in intraocular pressure during spinal surgery in prone position. A statistically significant retinal nerve fiber layer thickness thinning was seen in inferior and nasal quadrants one day after the spinal surgery.

Background and objectives

The importance of minimizing the exaggerated sympatho-adrenergic responses and QT interval and QT interval dispersion changes that may develop due to laryngoscopy and tracheal intubation during anesthesia induction in the hypertensive patients is clear. Esmolol decreases the hemodynamic response to laryngoscopy and intubation. However, the effect of esmolol in decreasing the prolonged QT interval and QT interval dispersion as induced by laryngoscopy and intubation is controversial. We investigated the effect of esmolol on the hemodynamic, and corrected-QT interval and corrected-QT interval dispersion changes seen during anesthesia induction in hypertensive patients using angiotensin converting enzyme inhibitors.

Methods

Sixty ASA I-II patients, with essential hypertension using angiotensin converting enzyme inhibitors were included in the study. The esmolol group received esmolol at a bolus dose of 500 mcg/kg followed by a 100 mcg/kg/min infusion which continued until the fourth minute after intubation. The control group received 0.9% saline similar to the esmolol group. The mean blood pressure, heart rate values and the electrocardiogram records were obtained as baseline values before the anesthesia, 5 min after esmolol and saline administration, 3 min after the induction, and 30 s, 2 min and 4 min after intubation.

Results

The corrected-QT interval was shorter in the esmolol group (P = .012), the corrected-QT interval dispersion interval was longer in the control group (P = .034) and the mean heart rate was higher in the control group (P = .022) 30 s after intubation. The risk of arrhythmia frequency was higher in the control group in the 4-min period following intubation (P = .038).

Conclusion

Endotracheal intubation was found to prolong corrected-QT interval and corrected-QT interval dispersion, and increase the heart rate during anesthesia induction with propofol in hypertensive patients using angiotensin converting enzyme inhibitors. These effects were prevented with esmolol (500 mcg/kg bolus, followed by 100 mcg/kg/min infusion). During induction, the blood pressure tends to decrease with esmolol where care is needed.

Background and objectives

It has been demonstrated that smoking increases pain perception; however the effect of smoking on perception of pain during venous cannulation is not known. The purpose of this study is to determine whether or not smoking has an effect on pain perception due to peripheral venous cannulation.

Methods

220 patients scheduled to have elective surgery were enrolled in the study and were divided into two groups (group S and C, n = 110 for each) according to their smoking habits. Numerical rating scale was introduced to the patients and then peripheral venous cannulation at the dorsum of the hand was made with a 20 G (Intracath^®). Pain perception of the patients was scored by subsequent numerical rating scale questioning.

Results

The demographic characteristics of the groups were identical. Numerical rating scale scores in group S and C were 3.31 ± 1.56 and 1.65 ± 1.23, respectively (P < .001).

Conclusion

Pain perception due to peripheral venous cannulation is higher in smokers. Future studies on pain treatment should consider the smoking habits of patients.

Background and objectives

Satellite glial cells in sensory ganglia are a recent subject of research in the field of pain and a possible therapeutic target in the future. Therefore, the aim of this study was to summarize some of the important physiological and morphological characteristics of these cells and gather the most relevant scientific evidence about its possible role in the development of chronic pain.

Content

In the sensory ganglia, each neuronal body is surrounded by satellite glial cells forming distinct functional units. This close relationship enables bidirectional communication via a paracrine signaling between those two cell types. There is a growing body of evidence that glial satellite cells undergo structural and biochemical changes after nerve injury, which influence neuronal excitability and consequently the development and/or maintenance of pain in different animal models of chronic pain.

Conclusions

Satellite glial cells are important in the establishment of physiological pain, in addition to being a potential target for the development of new pain treatments.