Spatial relationship of i-gel® and Ambu® AuraOnceTM on pediatric airway: a randomized comparison based on three dimensional magnetic resonance imaging.

BACKGROUND: Gross morphological differences exist among different brands of pediatric supraglottic devices (SGDs). The aim of this study is to compare the spatial relationship of i-gel® and Ambu® AuraOnce (AO)TM on pediatric airway based on three dimensional (3-D) magnetic resonance imaging (MRI) measurements. METHODS: Sixty patients up to 12 years of age were enrolled and assigned in two groups, i-gel® or Ambu® AOTM. After confirmation of proper placement of these SGDs, 3-D MRI scans of head and neck were performed. Another native scan was also obtained after removal of the SGD for comparison. RESULTS: i-gel® produced significant degree of compression of the tongue (P<0.001) while Ambu® AOTM significantly reduced the axial diameter of glottis (P=0.033) compared to their native values. Both i-gel® and Ambu® AOTM significantly reduced the area of the glottic opening (P<0.001 for each device) and the distance between the arytenoids (P<0.001 and P=0.007 respectively); and increased the distance between the hyoid bone and cervical spine (P<0.001 and P=0.001 respectively) in comparison to their corresponding native values. Bowl of i-gel® produced greater dilation of the upper esophageal sphincter at all levels of measurement- upper (P<0.001), middle (P=0.001) and lower (P=0.015) in comparison to Ambu® AOTM. CONCLUSIONS: Based on 3-D MRI measurements done on living patients, both SGDs distorted the anatomy of pediatric airway compared to their respective native values to variable extent. The relevance of these effects needs further studies on larger patient group in order to reduce morbidity on pediatric airway.

Critical incident monitoring in a teaching hospital--the third report 2003-2008.

UNLABELLED: Several factors have been incriminated in the etiologies of critical incidents: shortages in organizing rules, anesthesia technique, patient environment, human factor, team work and communication. This is the third follow up report describing our performance during the last five years (2003-2008). The possible incriminating causes were identified with the objective of avoiding such eventualities and consequently providing a better patient outcome. PATIENTS & METHODS: The computerized database and the medical records of critical incidents reports in our Department during the period of 2003-2008 were reviewed on case-by-case basis. Seventy reported incidents were discussed in the Department's Morbidity & Mortality Meetings (MMM). Incidents were classified as per possible incriminating causes: pulmonary, cardiovascular, central nervous system, metabolic, inadvertent drug injection, communicating failure, equipment failure and miscellaneous causes. RESULTS: Most of the critical incidents reports occurred during maintenance of anesthesia, followed next by during induction and next by same operative day later in the ward. The majority of cases were respiratory events (29 cases), followed by communication failure (12 cases), failure of equipment (9 cases) and inadvertent drug injection (4 cases). CONCLUSIONS: Respiratory events, human errors, team communication and equipment failures, continue to be the leading causes of critical incidents. Critical incidents are apt to occur so long as the human factor is involved. Vigilance in operational efficiency and the scrutiny in drug administration, supervision and training should be closely monitored in order to minimize critical incident reports.

Effect of fluid preloading on postoperative nausea and vomiting following laparoscopic cholecystectomy.

BACKGROUND: Postoperative nausea and vomiting (PONV) is a common complication following general anesthesia. Different regimens have been described for the treatment of PONV with few that mention the prevention of it. Therefore, we conducted this study to compare the effect of preloading with either crystalloids or colloids on the incidence of PONV following laparoscopic cholecystectomy (LC), under general anesthesia. MATERIALS AND METHODS: This study was carried out on 80 patients who underwent LC. The patients were divided into four groups (each 20 patients), to receive preloading of intravenous fluid, as follows: Group 1 received, 10 ml/kg of low-MW tetrastarch in saline (Voluven), group 2 received, 10 ml/kg medium-MW pentastarch in saline (Pentaspan), group 3, received 10 ml/kg of high-MW heta-starch in saline (Hespan), and group 4, received 10 ml/kg Lactated Ringer's, and this was considered as the control group. All patients received the standard anesthetic technique. The incidence of PONV was recorded, two and 24 hours following surgery. The need for antiemetics and/or analgesics was recorded postoperatively. RESULTS: The highest incidence of PONV was in group 3 (75% of the patients) compared to the other three groups. Also the same trend was found with regard to the number of patients who needed antiemetic therapy. It was the highest incidence in group 3 (70%), followed by group 2 (60%), and then group 1(35%), and the least one was in the control group (25%). CONCLUSION: Intravascular volume deficits may be a factor in PONV and preloading with crystalloids showed a lower incidence of PONV.

Anesthetic implications for video assisted thoracoscopic thymectomy in myasthenia gravis.

Thymectomy is an established therapy in the management of generalized myasthenia gravis (MG). However, the optimal surgical approach to thymectomy has remained controversial. There are advocates for transternal, transcervical approaches for "maximal" thymectomy. Video-assisted thoracoscopic thymectomy (VATT) presents new approach to thymectomy. By minimizing chest wall trauma, VATT not only causes less postoperative pain, shortens hospital stay, gives better cosmetic results but also leads to wider acceptance by patients for earlier surgery. Anesthesia for thymectomy in MG is challenging. Currently we are using non-muscle relaxant technique (NMRT) which we adopted in 1994, for maximal thymectomy. In this paper, we present our limited experience with two cases of VATT using two different NMRTs. Two cases of MG underwent VATT under general anesthesia (GA) and one lung ventilation (OLV) using double lumen tube (DLT). In both cases NMRT was used which encompass, light GA plus thoracic epidural analgesia (TEA) in one case and without TEA in the other case. We believe that the use of NMRT provides good operative and postoperative conditions. In this report we have described two different NMRTs, one with TEA and the other without. Further studies are needed on large number of cases to establish an anesthetic protocol for VATT.

Thoracoscopic sympathectomy: endobronchial anesthesia vs endotracheal anesthesia with intrathoracic CO2 insufflation.

PURPOSE: To compare clinical advantages and hemodynamic and respiratory changes during one lung-collapsed ventilation (OLCV) using a double-lumen tube (DLT) or a single-lumen tube (SLT) with intrathoracic CO(2) insufflation, in patients undergoing thoracic sympathectomy (TS) under general anesthesia. METHODS: One hundred and twenty-five patients (94 men and 31 women) undergoing TS for the treatment of palmar hyperhidrosis (PH) were randomly allocated to two groups: group A (68 patients; age, 29 +/- 6 years) in whom DLT was used, and group B (57 patients; age, 32 +/- 3 years) in whom SLT with intrathoracic CO(2) insufflation at a rate of 0.5-1 l.min(-1) and sustained intrathoracic pressure at 6 mmHg insufflation were used. Anesthesia was maintained with 1 minimum alveolar concentration (MAC) isoflurane in 50% nitrous oxide in oxygen with incremental doses of sufentanil and atracurium when required. Arterial blood gases were measured in 10 patients in group B. Hemodynamic and respiratory parameters were obtained perioperatively. RESULTS: There were no significant differences in hemodynamic and respiratory parameters between the two groups during the study phases, except for the arterial oxygen saturation (SpO(2)). The times required for anesthesia and surgery were significantly shorter in the SLT group than in the DLT group. SpO(2) during OLCV was 95 +/- 1% with DLT and 98 +/- 1% with SLT, with a significant difference. Three patients had an SpO(2) of less than 90% in the recovery room, where the chest tube position was readjusted, with no further sequelae. CONCLUSION: General anesthesia with SLT and intrathoracic CO(2) insufflation provides optimal operating conditions, adequate oxygenation, and perfect hemodynamic stability during TS.