Determination of Vecuronium Bromide in Pharmaceuticals: Development, Validation and Comparative Study of HPLC and CZE Analytical Methods

Vecuronium bromide is a neuromuscular blocking agent used for anesthesia to induce skeletal muscle relaxation. HPLC and CZE analytical methods were developed and validated for the quantitative determination of vecuronium bromide. The HPLC method was achieved on an amino column (Luna 150 x 4.6 mm, 5 mu m) using UV detection at 205 nm. The mobile phase was composed of acetonitrile:water containing 25.0 mmol L(-1) of sodium phosphate monobasic (50:50 v/v), pH 4.6 and flow rate of 1.0 mL min(-1). The CZE method was achieved on an uncoated fused-silica capillary (40.0 cm total length, 31.5 cm effective length and 50 mu m i.d.) using indirect UV detection at 230 nm. The electrolyte comprised 1.0 mmol L(-1) of quinine sulfate dihydrate at pH 3.3 and 8.0% of acetonitrile. The results were used to compare both techniques. No significant differences were observed (p > 0.05).

Improving the evidence base for anaesthesia

This paper is a brief report of the symposium, Improving the Evidence Base for Anaesthesia and Intensive Care, organized by the MASTER Anaesthesia Trial Study Group at the Annual Scientific Meeting of the Australian and New Zealand College of Anaesthetists, Newcastle, N.S.W. on Tuesday, May 5, 1998.

Epidural anaesthesia and analgesia and outcome of major surgery: a randomised trial

Background Epidural block is widely used to manage major abdominal surgery and postoperative analgesia, but its risks. and benefits are uncertain. We compared adverse outcomes in high-risk patients managed for major surgery with epidural block or alternative analgesic regimens with general anaesthesia in a multicentre randomised trial. Methods 915 patients undergoing major abdominal surgery with one of nine defined comorbid states to identify high-risk status were randomly assigned intraoperative epidural anaesthesia and postoperative epidural analgesia for 72 h with general anaesthesia (site of epidural selected to provide optimum block) or control. The primary endpoint was death at 30 days or major postsurgical morbidity. Analysis by intention to treat involved 447 patients assigned epidural and 441 control. Findings 255 patients (57.1%) in the epidural group and 268 (60.7%) in the control group had at least one morbidity endpoint or died (p=0.29). Mortality at 30 days was low in both groups (epidural 23 [5.1%], control 19 [4.3%], p=0.67). Only one of eight categories of morbid endpoints in individual systems (respiratory failure) occurred less frequently in patients managed with epidural techniques (23% vs 30%, p=0.02). Postoperative epidural analgesia was associated with lower pain scores during the first 3 postoperative days. There were no major adverse consequences of epidural-catheter insertion. Interpretation Most adverse morbid outcomes in high-risk patients undergoing major abdominal surgery are not reduced by use of combined epidural and general anaesthesia and postoperative epidural analgesia. However, the improvement in analgesia, reduction in respiratory failure, and the low risk of serious adverse consequences suggest that many high-risk patients undergoing major intra-abdominal surgery will receive substantial benefit from combined general and epidural anaesthesia intraoperatively with continuing postoperative epidural analgesia.

Perioperative epidural analgesia and outcome after major abdominal surgery in high-risk patients

In a primary analysis of a large recently completed randomized trial in 915 high-risk patients undergoing major abdominal surgery, we found no difference in outcome between patients receiving perioperative epidural analgesia and those receiving IV opioids, apart from the incidence of respiratory failure. Therefore, we performed a selected number of predetermined subgroup analyses to identify specific types of patients who may have derived benefit from epidural analgesia. We found no difference in outcome between epidural and control groups in subgroups at increased risk of respiratory or cardiac complications or undergoing aortic surgery, nor in a subgroup with failed epidural block (all P > 0.05). There was a small reduction in the duration of postoperative ventilation (geometric mean [SD]: control group, 0.3 [6.5] h, versus epidural group, 0.2 [4.8] h, P = 0.048). No differences were found in length of stay in intensive care or in the hospital. There was no relationship between frequency of use of epidural analgesia in routine practice outside the trial and benefit from epidural analgesia in the trial. We found no evidence that perioperative epidural analgesia significantly influences major morbidity or mortality after major abdominal surgery.

Sonification supports eyes-free respiratory monitoring and task time-sharing

Three experiments explored the effectiveness of continuous auditory displays, or sonifications, for conveying information about a simulated anesthetized patient's respiration. Experiment 1 established an effective respiratory sonification. Experiment 2 showed an effect of expertise in the use of respiratory sonification and revealed that some apparent differences in sonification effectiveness could be accounted for by response bias. Experiment 3 showed that sonification helps anesthesiologists to maintain high levels of awareness of the simulated patient's state while performing other tasks more effectively than when relying upon visual monitoring of the simulated patient state. Overall, sonification of patient physiology beyond traditional pulse oximetry appears to be a viable and useful adjunct to visual monitors. Actual and potential applications of this research include monitoring in a wide variety of busy critical care contexts.

Prostatic Artery Embolization as a Primary Treatment for Benign Prostatic Hyperplasia: Preliminary Results in Two Patients

Symptomatic benign prostatic hyperplasia (BPH) typically occurs in the sixth and seventh decades, and the most frequent obstructive urinary symptoms are hesitancy, decreased urinary stream, sensation of incomplete emptying, nocturia, frequency, and urgency. Various medications, specifically 5-alpha-reductase inhibitors and selective alpha-blockers, can decrease the severity of the symptoms secondary to BPH, but prostatectomy is still considered to be the traditional method of management. We report the preliminary results for two patients with acute urinary retention due to BPH, successfully treated by prostate artery embolization (PAE). The patients were investigated using the International Prostate Symptom Score, by digital rectal examination, urodynamic testing, prostate biopsy, transrectal ultrasound (US), and magnetic resonance imaging (MRI). Uroflowmetry and postvoid residual urine volume complemented the investigation at 30, 90, and 180 days after PAE. The procedure was performed under local anesthesia; embolization of the prostate arteries was performed with a microcatheter and 300- to 500-mu m microspheres using complete stasis as the end point. One patient was subjected to bilateral PAE and the other to unilateral PAE; they urinated spontaneously after removal of the urethral catheter, 15 and 10 days after the procedure, respectively. At 6-month follow-up, US and MRI revealed a prostate reduction of 39.7% and 47.8%, respectively, for the bilateral PAE and 25.5 and 27.8%, respectively, for the patient submitted to unilateral PAE. The early results, at 6-month follow-up, for the two patients with BPH show a promising potential alternative for treatment with PAE.

Online monitoring of pulse pressure variation to guide fluid therapy after cardiac surgery

BACKGROUND: The arterial pulse pressure variation induced by mechanical ventilation (Delta PP) has been shown to be a predictor of fluid responsiveness. Until now, Delta PP has had to be calculated offline (from a computer recording or a paper printing of the arterial pressure curve), or to be derived from specific cardiac output monitors, limiting the widespread use of this parameter. Recently, a method has been developed for the automatic calculation and real-time monitoring of Delta PP using standard bedside monitors. Whether this method is to predict reliable predictor of fluid responsiveness remains to be determined. METHODS: We conducted a prospective clinical study in 59 mechanically ventilated patients in the postoperative period of cardiac surgery. Patients studied were considered at low risk for complications related to fluid administration (pulmonary artery occlusion pressure <20 mm Hg, left ventricular ejection fraction >= 40%). All patients were instrumented with an arterial line and a pulmonary artery catheter. Cardiac filling pressures and cardiac output were measured before and after intravascular fluid administration (20 mL/kg of lactated Ringer`s solution over 20 min), whereas Delta PP was automatically calculated and continuously monitored. RESULTS: Fluid administration increased cardiac output by at least 15% in 39 patients (66% = responders). Before fluid administration, responders and nonresponders were comparable with regard to right atrial and pulmonary artery occlusion pressures. In contrast, Delta PP was significantly greater in responders than in nonresponders, (17% +/- 3% vs 9% +/- 2%, P < 0.001). The Delta PP cut-off value of 12% allowed identification of responders with a sensitivity of 97% and a specificity of 95%. CONCLUSION: Automatic real-time monitoring of Delta PP is possible using a standard bedside rnonitor and was found to be a reliable method to predict fluid responsiveness after cardiac surgery. Additional studies are needed to determine if this technique can be used to avoid the complications of fluid administration in high-risk patients.

Smart Alerts: Development of Software to Optimize Data Monitoring

Dherte PM, Negrao MPG, Mori Neto S, Holzhacker R, Shimada V, Taberner P, Carmona MJC - Smart Alerts: Development of a Software to Optimize Data Monitoring. Background and objectives: Monitoring is useful for vital follow-ups and prevention, diagnosis, and treatment of several events in anesthesia. Although alarms can be useful in monitoring they can cause dangerous user`s desensitization. The objective of this study was to describe the development of specific software to integrate intraoperative monitoring parameters generating ""smart alerts"" that can help decision making, besides indicating possible diagnosis and treatment. Methods: A system that allowed flexibility in the definition of alerts, combining individual alarms of the parameters monitored to generate a more elaborated alert system was designed. After investigating a set of smart alerts, considered relevant in the surgical environment, a prototype was designed and evaluated, and additional suggestions were implemented in the final product. To verify the occurrence of smart alerts, the system underwent testing with data previously obtained during intraoperative monitoring of 64 patients. The system allows continuous analysis of monitored parameters, verifying the occurrence of smart alerts defined in the user interface. Results: With this system a potential 92% reduction in alarms was observed. We observed that in most situations that did not generate alerts individual alarms did not represent risk to the patient. Conclusions: Implementation of software can allow integration of the data monitored and generate information, such as possible diagnosis or interventions. An expressive potential reduction in the amount of alarms during surgery was observed. Information displayed by the system can be oftentimes more useful than analysis of isolated parameters.

Myotomy of the Levator Labii Superioris Muscle and Lip Repositioning: A Combined Approach for the Correction of Gummy Smile

Background: Treatment of excessive gingival display usually involves procedures such as Le Fort impaction or maxillary gingivectomies. The authors propose an alternative technique that reduces the muscular function of the elevator of the upper lip muscle and repositioning of the upper lip. Methods: Fourteen female patients with excessive gingival exposure were operated on between February of 2008 and March of 2009. They were filmed before and at least 6 months after the procedure. They were asked to perform their fullest smile, and the maximum gingival exposures were measured and analyzed using ImageJ software. Patients were operated on under local anesthesia. Their gingival mucosa was freed from the maxilla using a periosteum elevator. Skin and subcutaneous tissue were dissected bluntly from the underlying musculature of the upper lip. A frenuloplasty was performed to lengthen the upper lip. Both levator labii superioris muscles were dissected and divided. Results: The postoperative course was uneventful in all of the patients. The mean gingival exposure before surgery was 5.22 +/- 1.48 mm; 6 months after surgery, it was 1.91 +/- 1.50 mm. The mean gingival exposure reduction was 3.31 +/- 1.05 mm (p < 0.001), ranging from 1.59 to 4.83 mm. Conclusion: This study shows that the proposed technique was efficient in reducing the amount of exposed gum during smile in all patients in this series. (Plast. Reconstr. Surg. 126: 1014, 2010.)

Transanal endorectal pull-through in children with Hirschsprung`s disease-technical refinements and comparison of results with the Duhamel procedure

Purpose: Transanal endorectal pull-through (TEPT) has drastically changed the treatment of Hirschsprung`s disease (HD). A short follow-up of children Submitted to TEPT reveals results that are similar to the classic transabdominal pull-through procedures. However, few reports compare the late results of TEPT with transabdominal pull-through procedures with respect to complication rates and the fecal continence. The aims of the present work are to describe some technical refinements that we introduced in the procedure and to compare the short and long-term outcome of TEPT with the outcomes of a group of patients with HD who previously underwent the Duhamel procedure. Methods: Thirty-five patients who underwent TEPT were prospectively studied and compared to a group of 29 patients who were treated with colostomy followed by a classical Duhamel pull-through. The main modifications introduced in the TEPT group were no preoperative colon preparation, operation conducted under general anesthesia in addition to regional sacral anesthesia, use of only one purse-string Suture in the rectal mucosa before transanal submucosal dissection, and no use of retractors and electrocautery during file submucosal dissection. Results: The most frequent early complications of TEPT group were perineal dermatitis (22.8%) and anastomotic strictures (8.6%). The comparison with patients who underwent Duhamel procedure revealed no difference in the incidence of preoperative enterocolitis, the patients of the TEPT group were younger at the time of diagnosis and of surgery, they had shorter operating times, and they began oral feeding more quickly after the operation. The incidence of wound infection was lower in the TEPT group. Moreover, the TEPT and Duhamel groups showed no difference in the incidences of mortality, postoperative partial continence, and total incontinence. Although the incidences of complete continence and postoperative enterocolitis were not different, a tendency to the increased incidence in the TEPT group was observed. Conclusions: This study further supports the technical advantages, the simplicity, and the decreased incidence of complications of a primary TEPT procedure when compared to a classical form of pull-through. Sonic technical refinements are described, and no preoperative colon preparation was necessary for the patients studied here. The results show that the long-term outcomes of the modified TEPT procedure are generally better than those obtained with classical approaches. Published by Elsevier Inc.

Fast-track rehabilitation for lung cancer lobectomy: a five-year experience

Objective: Fast-track rehabilitation is a group of simple measures that reduces morbidity, postoperative complication and accelerates postoperative rehabilitation reducing hospital stay. It can be applied to lung cancer lobectomy. Fast-track rehabilitation cornerstones are: minimally invasive surgical techniques using video-assisted and muscle sparring incisions, normovolemia, normothermia, good oxygenation, euglicemia, no unnecessary antibiotics, epidural patient-controlled analgesia, systemic opiods-free analgesia, early ambulation and oral feeding. Our objective is to describe a five-year experience with fast-track rehabilitation for lung cancer lobectomy. Patients and methods: A retrospective non-controlled study including 109 consecutive patients submitted to fast-track rehabilitation in the postoperative care of lung cancer lobectomy was performed. Only collaborative patients who could receive double-lumen intubation, epidural. catheters with patient-controlled analgesia, who had Karnofsky index of 100, previous normal feeding and ambulation, absence of morbid obesity, diabetes or asthma, were eligible. Postoperative oral feeding and aggressive ambulation started as soon as possible. Results: Immediate postoperative extubation even in the operation room was possible in 107 patients and oral feeding and ambulation were possible before the first hour in 101 patients. Six patients could not receive early oral feeding or ambulate due to hypnosis secondary to preoperative long effect benzodiazepines. Two patients could not ambulate immediately due to epidural catheter misplacement with important postoperative pain. Ninety-nine discharges occurred at the second postoperative day, four of them with a chest tube connected to a Heimlich valve due to air teak. No complication of early feeding and ambulation was observed. Postoperative hypnosis due to long duration benzodiazepines or pain does not allow early oral feeding or ambulation. Avoiding long duration preoperative benzodiazepines, immediate postoperative extubation, regional thoracic PCA and early oral feeding and ambulation were related to a lesser frequency of complication and a shorter hospital stay. Conclusion: Fast-track rehabilitation for lung cancer lobectomies can be safety performed in a selected group of patients if a motivated multidisciplinary group of professionals is available and seems to reduce postoperative complication and hospital stay. (C) 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.