Incidence of adhesions in patients using liraglutide before laparoscopic sleeve gastrectomy.

BACKGROUND: The current study objectively identified the incidence of adhesions between the stomach and pancreas in laparoscopic sleeve gastrectomy (LSG) patients on liraglutide (cases group) and off (control group) liraglutide. METHODS: This observational prospective study was conducted in the Department of General Surgery at Saudi German Hospital, Al-Aseer, Saudi Arabia (SGH) after approval by the Institutional Review Board. 117 patients with prior use of liraglutide and 101 patients with no liraglutide use scheduled for LSG over 12 months were included. Inclusion criteria included patients undergoing LSG with or without prior use of liraglutide. Exclusion criteria included patients with prior abdominal surgeries, bariatric surgery revisions, prior upper GI scope showing gastritis, Gastroesophageal Reflux Disease (GERD) or any other pathology, and other known causes of other causes of pancreatitis. Using laparoscopy obtained imaging during LSG cases adhesions between the posterior stomach and pancreas were identified. RESULTS: The mean age of the patients in the cases and control groups was 32.44 ± 9.90 years and 28.23 ± 8.48 years (p = 0.001). The mean BMI of patients in the cases and control groups was 43.56 ± 4.59 and 45.00 ± 4.78, respectively (p = 0.024). 85% of the patients were females, while 17.0% were males in the cases group. 53.5% of the patients were females, while 47.0% were males in the control group (p < 0.001). In the cases group, 48.7% of patients had stopped liraglutide for no obvious reason. Under the cases group, 77.8% of the patients had no adhesions, while 22.2% had adhesions. Under the controls group, no adhesions were seen (p < 0.001). CONCLUSIONS: Our results for the first time demonstrate an incidence of adhesions in 22.2% of patients undergoing LSG on prior liraglutide intake (p < 0.001). This study brings to light the possibility of adhesions in patients with prior exposure to liraglutide undergoing LSG. Surgeons performing LSG in patients with prior exposure to liraglutide should be cognizant of this possibility, thereby requiring careful meticulous dissection.

Comparison of the Fitbit® charge and polysomnography for measuring sleep quality in children with sleep disordered breathing.

BACKGROUND: Due to the cost and inconvenience of polysomnography (PSG), wrist-worn accelerometers have been explored as an alternative method to measure sleep efficacy in children with obstructive sleep apnea (OSA) or sleep-disordered breathing (SDB). We compared the measurement of sleep quality with the Fitbit® charge (Fitbit Inc., San Francisco, CA, USA) compared to PSG in children presenting for sleep studies. METHODS: Children ages 3 to 18 years presenting for PSG with persistent SDB symptoms were enrolled. During PSG, the Fitbit® charge (Fitbit Inc.) was placed on the wrist and time-synchronized with sleep laboratory devices, which were worn while a single-night PSG was performed. Bias and concordance in measurements of total sleep time (TST), total wake time (TWT), and number of awakenings were assessed using paired t-tests, sign-rank tests, and Lin's concordance coefficient. RESULTS: The study cohort included 22 patients (9 boys and 13 girls; 9±3 years). TST was significantly overestimated using the Fitbit® charge (Fitbit Inc.) (difference in means: 30 min; 95% confidence interval [CI] of difference: 3-58; P=0.031), while TWT was underestimated (difference: 23 min; 95% CI: 4-42; P=0.018). All measures showed a lack of concordance between the Fitbit® charge (Fitbit Inc.) and PSG. CONCLUSIONS: The current prospective study confirms that the Fitbit® charge (Fitbit Inc.) overestimates time spent asleep compared to PSG in children with OSA/SDB symptoms, limiting the validity of sleep monitoring with wearable activity trackers appears in these patients.

Surgical management of subhepatic perforated appendicitis: a case report.

BACKGROUND: Subhepatic appendicitis is an exceedingly rare presentation, accounting for 0.01% of acute appendicitis cases. It is of prime importance to be aware of variants and manage such challenging cases accordingly. CASE PRESENTATION: We present a case of a middle-aged Saudi woman with subhepatic perforated appendicitis and peritonitis who underwent an exploratory laparotomy and appendectomy. CONCLUSIONS: The initial diagnosis and surgical management of such patients is challenging due to an atypical presentation. The surgical management of such patients is discussed with a brief review of the literature.

A Comparison of Direct Laryngoscopy and Videolaryngoscopy for Endotracheal Intubation by Inexperienced Users: A Pediatric Manikin Study.

OBJECTIVE: Direct laryngoscopy (DL) is the most common technique for endotracheal intubation, whereas videolaryngoscopy provides an indirect view of the glottis without the need to align the oral, pharyngeal, and tracheal axes. The current study compares videolaryngoscopy with DL among experienced and inexperienced users for endotracheal intubation using a pediatric manikin. METHODS: Participants performed DL using Miller and Macintosh laryngoscopes and videolaryngoscopy using CMAC and GlideScope devices on a manikin (SimBaby; Laerdel, Wappingers Falls, NY). Time to endotracheal intubation, number of attempts, and successful intubation within 120 seconds were recorded. RESULTS: Among 31 experienced users, time to endotracheal intubation with the CMAC (20 ± 13 seconds) did not differ from DL with either the Miller (30 ± 28 seconds) or Macintosh (27 ± 23 seconds) laryngoscopes. However, with the GlideScope, time to endotracheal intubation (85 ± 38 seconds) was longer. The results were similar among 12 inexperienced users, as time to endotracheal intubation with the CMAC (61 ± 34 seconds) was comparable with the Miller (72 ± 45 seconds) or Macintosh (72 ± 45 seconds) laryngoscopes but was longer with the GlideScope (118 ± 6 seconds) for each comparison. CONCLUSIONS: The standard straight or curved laryngoscope blades including the CMAC were associated with shorter procedural time and higher success rate when compared with indirect videolaryngoscopy with an unconventional blade design such as the GlideScope in both experienced and inexperienced users. However, the current study demonstrates that results may be influenced by the anatomical design of the manikin.

The Effect of Operating Room Temperature on the Performance of Clinical and Cognitive Tasks.

INTRODUCTION: Operating room (OR) temperature may impact the performance of health care providers. This study assesses whether hot or cold room temperature diminishes the performance of OR personnel measured by psychomotor vigilance testing (PVT) and self-report scales. METHODS: This prospective observational study enrolled surgical/anesthesia trainees, student registered nurse anesthetists, and certified registered nurse anesthetists. Each provider participated in a test of psychomotor function and a questionnaire using a self-report scale of personal comfort and well-being. The PVT and questionnaires were completed after 30 minutes of exposure to 3 different conditions (temperature of 21°C, 23°C, and 26°C). RESULTS: The cohort of 22 personnel included 9 certified registered nurse anesthetists, 7 anesthesia/surgical trainees, and 6 student registered nurse anesthetists. Mean reaction time on the PVT was comparable among baseline (280 ± 47 ms), hot (286 ± 55 ms; P = 0.171), and cold (303 ± 114 ms; P = 0.378) conditions. On the self-report score (range, 1-21), there was no difference in the self-rated subjective performance between baseline and cold conditions. However, the self-rated subjective performance scale was lower (12 ± 6, P = 0.003) during hot conditions. DISCUSSION: No difference was noted in reaction time depending on the temperature; however, excessive heat in the OR environment was associated with worse self-rated subjective performance among health care providers. Particularly, self-rated subjective physical demand and frustration were greater under hot condition.

A comparison of supraglottic devices in pediatric patients.

BACKGROUND: When managing patients with a difficult airway, supraglottic airways (SGAs) have been used as rescue devices or to serve as a conduit for endotracheal intubation. The current study compares various clinical outcomes, including the bronchoscopic view of the glottis when using 2 SGAs, the Air-Q® laryngeal mask airway (LMA) and the i-gel® SGA, in pediatric patients. METHODS: Patients ≤18 years of age were prospectively randomized to receive either the Air-Q® LMA or the i-gel® SGA. Following SGA placement, a flexible fiberoptic bronchoscope was inserted through the SGA to visualize the glottis. Time taken to obtain the bronchoscopic view and place the SGA, and the ability to seal the airway at 20 cmH2O were compared. The bronchoscopic view obtained was graded as follows: 1) glottic aperture seen completely; 2) glottic aperture seen partially with visual obstruction <50%; 3) glottic aperture seen, but visual obstruction >50%; and 4) glottic aperture not seen. RESULTS: Fifty patients were enrolled and 48 (22/26 male/female) were included in the analysis. Median age was 13 years (IQR: 7, 16) and median weight was 49 kg (IQR: 25, 70). The Air-Q® LMA and i-gel® SGA groups did not differ in device placement time (median of 19 vs 21 seconds; 95% CI of difference in medians: - 2 to 7; P=0.331), the time to achieve fiberoptic view of the glottis (median of 25 vs 21 seconds; 95% CI of difference: - 9 to 8; P=0.489) or the grade of the bronchoscopic view of the airway. Eight Air-Q® and 6 i-gel® supraglottic devices sealed the airway at 20 cmH2O. DISCUSSION: The time required for successful placement of the SGA, the time required for bronchoscopic view, and the quality of bronchoscopic view through the Air-Q® LMA and the i-gel® SGA did not differ.

Changes in tissue and cerebral oxygenation following spinal anesthesia in infants: a prospective study.

Use of spinal anesthesia (SA) in children may address concerns about potential neurocognitive effects of general anesthesia. We used near-infrared spectroscopy (NIRS) to assess the effects of SA on cerebral and tissue oxygenation in 19 patients aged 7 ± 3 months. Prior to SA placement, NIRS monitors were placed on the forehead (cerebral) and the thigh (tissue). Intraoperative cerebral and tissue saturation were 73 ± 7 and 80 ± 11%, respectively, before SA placement. NIRS measurements were monitored every minute for 30 min after SA placement and modeled using mixed-effects linear regression. Regression estimates showed that cerebral saturation remained stable from 67% [95% confidence interval (CI) 63, 71%] after SA placement to 68% (95% CI 65, 72%) at the conclusion of monitoring. After SA placement, tissue saturation was elevated compared to baseline values; but further change [from 91% (95% CI 89, 93%) to 93% (95% CI 91, 95%) at the end of monitoring] was clinically non-significant. All patients breathed spontaneously on room air without changes in oxygen saturation. Blood pressure and heart rate decreased after SA placement, but no changes in hemodynamic parameters required treatment. These data provide further evidence of the neutral effect of SA on cerebral oxygenation 30 min after block placement.

Sugammadex to reverse neuromuscular blockade and provide optimal conditions for motor-evoked potential monitoring.

Sugammadex is a novel pharmacologic agent, which reverses neuromuscular blockade (NMB) via a mechanism that differs completely from acetylcholinesterase inhibitors. By encapsulating rocuronium, sugammadex can provide recovery of neuromuscular function even when there is a profound degree of NMB. We report anecdotal experience with the use of sugammadex to reverse NMB to facilitate intraoperative neurophysiological monitoring (motor evoked potentials) in an adolescent with scoliosis during posterior spinal fusion. Its potential application in this unique clinical scenario is discussed, and potential dosing schemes are reviewed.

An In Vitro Assessment of the Efficacy of Various IV Cannulas for the Rapid IV Fluid Administration.

OBJECTIVES: The current study prospectively evaluates the administration of fluid through commonly used vascular cannulas of various length and diameter. DESIGN: Observational, in vitro experiment. SETTING: Not applicable. SUBJECTS: No human subjects. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Fluid (500 mL) was administered via gravity flow and with pressure assistance (pressure bag set at 300 mm Hg) through various vascular cannulas including peripheral IV catheters (22 gauge, 1 inch; 20 gauge, 1.16 and 1.88 inch; and 18 gauge, 1.16 and 1.88 inch), 3-Fr central line lumens (lengths 50, 80, and 120 mm), and a 4-Fr, 10 cm Micropuncture catheter (Cook Medical, Bloomington, IN). During gravity flow, drain time decreased by approximately 50% when moving from a 22 to 20 to 18 gauge cannula and increased by approximately 20% as the catheter length increased from 50 to 80 to 120 cm. Flow rates were highest with the Micropuncture catheter, which achieved a drain time of 2.7 minutes for the 500 mL bag when infused with pressure assistance. CONCLUSIONS: In general, the delivery of crystalloid solutions through commonly used vascular cannulas was fastest with larger diameter and shorter length cannulas. Pressure-assisted flow was able to partially compensate for the increased resistance with smaller and longer catheters. The unique design of the tip of the Micropuncture catheter compensated for the increased length and allowed for rapid fluid delivery. This design may compensate for the increased length when longer catheters are needed for ultrasound-guided placement.

Cuffed endotracheal tubes in children: the effect of the size of the cuffed endotracheal tube on intracuff pressure.

BACKGROUND: In children, the size of the cuffed endotracheal tube is based on various age-based formulas. However, such formulas may over or underestimate the size of the cuffed endotracheal tube. There are no data on the impact of different-sized cuffed endotracheal tubes (ETT) on the intracuff pressure in children. AIM: The current study measures intracuff pressure with different-sized cuffed ETT. METHOD: The study was conducted in an in vitro and in vivo phase. For the in vitro phase, 10 cuffed ETT of size 4.0, 4.5, and 5 mm internal diameter (ID) each were randomly placed inside a 1.0 cm ID plastic tube (mimicking the trachea), which was in turn connected to a 1 l test lung. After inflation of the cuff using the air leak test at a continuous positive airway pressure of 20 cmH2 O, the intracuff pressure was measured. The in vivo phase was conducted in 100 children (4-8 years) and were randomly divided into two groups to receive either a cuffed endotracheal tube based on the Khine formula (Group R) or a cuffed endotracheal tube that was a half-size (0.5 mm ID) smaller (Group S). Following the inflation of the cuff to seal the trachea, the intracuff pressure was measured. RESULTS: In the in vitro phase, the intracuff pressure was 45 ± 6, 23 ± 1, and 14 ± 6 cmH2 O with size 4.0, 4.5, and 5 mm ID cuffed ETT, respectively (F-test P < 0.001 for difference among three groups). In the in vivo phase, the mean intracuff pressure in Group R was 25 ± 19 cmH2 O vs 37 ± 35 cmH2 O in Group S (95% CI of difference: 1, 23; P = 0.039). CONCLUSION: If the cuffed endotracheal tube is too small, the trachea can still be sealed by inflating the cuff with additional air. However, this transforms the cuff from the intended high-volume, low-pressure cuff to an undesirable high-volume, high-pressure cuff.

The Effect of Transesophageal Echocardiography Probe Placement on Intracuff Pressure of an Endotracheal Tube in Infants and Children.

OBJECTIVES: To evaluate the effects of transesophageal echocardiography (TEE) probe insertion on the endotracheal cuff pressure (CP). DESIGN: Prospective observational study. SETTING: Single standing, not-for-profit pediatric hospital. PARTICIPANTS: A total of 80 pediatric patients (aged 6 days to 18.4 years) who underwent cardiac surgery and intraoperative TEE. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Following anesthesia induction and endotracheal intubation, the CP was recorded at 4 points: before the insertion of the TEE (P1), at TEE insertion (P2), during TEE examination (P3), and after the probe was advanced into the stomach (P4). Twenty patients were enrolled in each of the following age groups:<1 year of age; 1-4 years of age; 5-8 years of age; and 9-18 years of age. CP was compared between pairs of time points using paired t-tests, and differences in CP over time were compared among age groups using repeated-measures analysis of variance. CP at P1, P2, P3, and P4 was 18.7±11.6, 26.7±14.4, 22.3±12.4, and 20.6±12.6 cmH2O, respectively. Although CP significantly increased from P1 to P2 (p<0.001), there was no significant difference between P1 and P4 (95% CI; -0.3 to 4.1; p = 0.083). There was no significant difference in CP change based on the age of the patient. CONCLUSION: Following a transient increase in CP with TEE probe insertion, the CP returned to baseline after the tip of the TEE probe was advanced into the stomach. There was no variation among age groups in the magnitude of the CP change during the study.

The effect of esophagogastroduodenoscopy probe insertion on the intracuff pressure of airway devices in children during general anesthesia.

Given the size of the esophagogastroduodenoscopy (EGD) probe and the compressibility of the pediatric airway, the EGD probe may increase the intracuff pressure (IP) of an airway device. The current study evaluated IP changes during EGD examination under general anesthesia in pediatric patients. Following the induction of anesthesia, a laryngeal mask airway (LMA) or endotracheal tube (ETT) was placed without neuromuscular blockade. The IP was measured at baseline, during EGD probe insertion, while the EGD probe was in place, and after probe removal. The study cohort included 101 patients (mean age 11.3 years). The airway was secured with an LMA and an ETT in 88 and 13 patients, respectively. The IP increased from 27 ± 15 cmH2O at baseline to 34 ± 17 cmH2O during probe insertion (p < 0.001), remained at 33 ± 16 cmH2O while the probe was in place, and decreased to 26 ± 14 cmH2O after probe removal. The IP of the LMA or ETT increased during EGD probe insertion and remained elevated while the probe was in place. High IP may compromise mucosal perfusion resulting in a sore throat when using an LMA or the potential for airway damage if an ETT is used. Removal of air from the cuff and titration of the IP should be considered after EGD insertion.

Changes in Cerebral Oxygenation during Transfusion Therapy.

This study assesses the effects of transfusion of autologous or allogeneic blood on cerebral and tissue oxygenation during spinal surgery. Packed red blood cell transfusions are indicated to improve oxygen delivery to tissues. There are limited data demonstrating changes in tissue oxygenation with blood administration. Tissue (deltoid) and cerebral oxygenation were monitored using near-infrared spectroscopy during spinal surgery in patients. As indicated, cell saver or allogeneic blood was administered. Tissue and cerebral oxygenation were recorded before and after transfusion. The study enrolled 50 patients, 33 of whom (17 males and 16 females) received allogeneic blood (n = 8) or autologous blood (n = 25). Patients ranged in age from 9 to 19 years (14.0 ± 2.3 years) and in weight from 16.8 to 122.7 kg (54.6 ± 25.7 kg). Tissue oxygenation increased from 83 ± 9 (pretransfusion) to 86 ± 7 at the end of transfusion (p = .002) and remained at the same level (86 ± 7) in the post-transfusion period. Cerebral oxygenation increased from 76 ± 8 (pretransfusion) to 84 ± 8 at the end of transfusion (p < .001) and remained at 84 ± 8 in the post-transfusion period. Changes in tissue and cerebral oxygenation were similar between cell saver and allogeneic blood and between starting hemoglobin value <8 gm/dL and starting hemoglobin ≥8 gm/dL. In conclusion, although both cerebral and tissue oxygenation increased during the administration of either allogeneic or autologous blood, the clinical impact was likely limited given the high initial tissue and cerebral oxygenation values. No differences were noted between autologous (cell saver) and allogeneic blood or based on the starting hemoglobin value.

Femoral nerve blockade using various concentrations of local anesthetic for knee arthroscopy in the pediatric population.

BACKGROUND: Femoral nerve blockade (FNB) provides effective postoperative analgesia in children undergoing arthroscopic knee surgery as evidenced by their opioid-sparing effects and decreased postoperative pain scores. Increasing the local anesthetic concentration in peripheral nerve blockade for adults undergoing orthopedic surgery has been shown to be beneficial, increasing block success rate, and providing a longer duration of analgesia. The effect of increasing the concentration of local anesthetic in extremity blocks in children remains largely unexplored. METHODS: We retrospectively evaluated the effectiveness of FNB using three concentrations of local anesthetic (ropivacaine 0.2%, bupivacaine 0.25%, and ropivacaine 0.5%) in children and adolescents undergoing arthroscopic knee surgery. The primary outcome evaluated was postoperative opioid consumption before discharge. Secondary outcomes included post-anesthesia care unit (PACU) and hospital discharge times, first pain score in PACU, and the incidence of adverse events. RESULTS: Two hundred and sixty-nine children and adolescents who received a FNB for arthroscopic knee surgery from January 2010 to December 2013 were included for analysis. Local anesthetic used in FNB was ropivacaine 0.2% in 116 (43%) cases, ropivacaine 0.5% in 75 (28%) cases, and bupivacaine 0.25% in 78 (29%) cases. Median postoperative opioid consumption (mg/kg intravenous morphine equivalents) in the ropivacaine 0.5% group was 0 mg/kg (interquartile ranges [IQR]: 0 mg, 0.03 mg/kg) compared to 0.02 mg/kg (IQR: 0, 0.08 mg/kg) in the ropivacaine 0.2% group and 0.01 mg/kg (IQR: 0, 0.08 mg/kg) in the bupivacaine 0.25% group (p=0.009). Median PACU time was shortest in the ropivacaine 0.5% group (47 min; IQR: 36, 68 min) compared to the ropivacaine 0.2% (58 min; IQR: 41, 77) and bupivacaine 0.25% (54 min; IQR: 35, 75 min) groups (p=0.040). Among groups, there were no significant differences in first postoperative pain scores or incidence of nausea and vomiting. No patient in any group experienced a serious adverse event. CONCLUSION: The results suggest that ropivacaine 0.5% for FNB offers superior postoperative analgesia in the form of decreased postoperative opioid consumption and earlier PACU/hospital discharge, when compared to ropivacaine 0.2% and bupivacaine 0.25% in the pediatric population. LEVEL OF EVIDENCE: III, Retrospective Comparative Study.

Oxymetazoline Metered Dose Spray: Factors Affecting Delivery Volume.

OBJECTIVES: The current study compared the amount of oxymetazoline delivered by various anesthesia providers when holding the bottle in the upright and inverted position. Additionally, the amount delivered from a full bottle and a half-full bottle was also investigated. METHODS: Using an analytical balance that was calibrated to zero, we evaluated the impact the position of the bottle and the volume of oxymetazoline in the bottle had on the amount being delivered by both anesthesia staff and trainees. RESULTS: When using both filled and half-filled bottles, the amount delivered increased significantly when comparing the upright versus inverted position. With a full bottle, the amount delivered when the bottle was inverted increased almost 10-fold from 62 ± 80 to 606 ± 366 µL (p < 0.0001). Similarly, even with a half-filled bottle, the amount delivered increased in the inverted positions from 41 ± 48 to 645 ± 393 µL. Regardless of the scenario, we also noted significant variation from provider to provider. CONCLUSIONS: Our results demonstrate that several factors may affect the amount of oxymetazoline delivered for metered dose bottles. Given the potential for severe end-organ effects with excessive dosage, alternative means of delivery are needed for its perioperative use.

Residual volume in the cuff of the endotracheal tube when the pilot balloon is torn off instead of deflated using a syringe.

BACKGROUND: In recent years, there has been a shift in airway management with the use of cuffed endotracheal tubes (ETT) in pediatric patients. While the use of a syringe to deflate the cuff is generally recommended, anecdotal observations suggest that some healthcare practitioners tear off the pilot balloon from ETT to deflate the cuff. This study was conducted to estimate the residual volume in the cuff when the pilot balloon is torn off for deflation. METHOD: The in vitro study was conducted in three phases. In phases 1 and 2, various sized cuffed ETTs (3.0, 4.0, and 5.0 mm) were inflated to achieve an intracuff pressure of 20-30 cmH2O in open atmosphere (phase 1) or inside a tube to simulate external pressure from the tracheal wall (phase 2). The pilot balloons were ripped off and the residual volume in the cuff was measured. The process was repeated using 10 ETTs of each of the 3 sizes. In phase 3, the same process was repeated using ten, size 7.0 cuffed ETTs inflated in an intubating mannequin. RESULTS: In phase 1, the percentage of the remaining residual volume was 60.7, 72.8, and 69.5% in 3.0, 4.0, and 5.0 mm ETTs respectively. Although the percentage of residual volume in phases 2 and 3 was less than phase 1, the residual volume in phases 2 and 3 still averaged approximately 60-70% of the volume required for cuff inflation. In one case, the pilot balloon tube was completely occluded and the residual volume in the cuff could not be expelled even with external pressure. CONCLUSION: Since significant percentage of the volume remained in the cuff after tearing off the pilot balloon tube with one being completely occluded, we would not recommend this method for cuff deflation.

Oropharyngeal oxygen and volatile anesthetic agent concentration during the use of laryngeal mask airway in children.

BACKGROUND: The laryngeal mask airway is increasingly used as an airway adjunct during general anesthesia. Although placement is generally simpler than an endotracheal tube, complete sealing of the airway may not occur, resulting in contamination of the oropharynx with anesthetic gases. Oropharyngeal oxygen enrichment may be one of the contributing factors predisposing to an airway fire during adenotonsillectomy. The current study prospectively assesses the oropharyngeal oxygen and volatile anesthetic agent concentration during laryngeal mask airway use in infants and children. METHODS: Following the induction of general anesthesia and placement of a laryngeal mask airway, the oropharyngeal gas sample was obtained by placing a 14-gauge catheter attached to the gas sampling tube into the oropharynx above the laryngeal mask airway. The oropharyngeal concentration of the oxygen and the anesthetic agent were recorded for five breaths during both spontaneous ventilation (SV) and positive pressure ventilation (PPV). RESULTS: The study included 238 patients. The oropharyngeal concentration of sevoflurane was >50% of the inspired sevoflurane concentration during SV in 10 of 238 (4.2%) patients and during PPV in 135 of 238 (56.7%) patients. Similarly, during SV and PPV, the oropharyngeal oxygen concentration was >21% in 30 of 238 (12.6%) patients and in 188 of 238 (79%) patients, respectively. Significantly, we also noticed that the oropharyngeal oxygen concentration exceeded 50% in 5 of 238 (2.1%) patients during SV and in 139 of 238 patients (58.4%) patients during PPV. CONCLUSIONS: With the use of a laryngeal mask airway and the administration of 100% oxygen, there was significant contamination of the oropharynx during both PPV and SV. The oropharyngeal concentration of oxygen was high enough to support combustion in a significant number of patients. The use of a laryngeal mask airway does not ensure sealing of the airway and may be one risk factor for an airway fire during adenotonsillectomy.

Regional anesthesia for an upper extremity amputation for palliative care in a patient with end-stage osteosarcoma complicated by a large anterior mediastinal mass.

Tumor progression during end-of-life care can lead to significant pain, which at times may be refractory to routine analgesic techniques. Although regional anesthesia is commonly used for postoperative pain care, there is limited experience with its use during home hospice care. We present a 24-year-old male with end-stage metastatic osteosarcoma who required anesthetic care for a right-sided above-the-elbow amputation. The anesthetic management was complicated by the presence of a large mediastinal mass, limited pulmonary reserve, and severe chronic pain with a high preoperative opioid requirement. Intraoperative anesthesia and postoperative pain management were provided by regional anesthesia using an interscalene catheter. He was discharged home with the interscalene catheter in place with a continuous local anesthetic infusion that allowed weaning of his chronic opioid medications and the provision of effective pain control. The perioperative applications of regional anesthesia in palliative and home hospice care are discussed.

SUBMUCOSAL DISSECTION OF THE RETROPHARYNGEAL SPACE DURING NASAL INTUBATION.

Various complications have been reported with nasal endotracheal intubation including bleeding, epistaxis, bacteremia, damage to intranasal structures, and even intracranial penetration. We present two cases that required general anesthesia for dental surgery. Submucosal dissection of the retropharyngeal tissues occurred during attempted nasal endotracheal intubation. Previous reports of this complication are reviewed, treatment strategies presented, and potential maneuvers to prevent this complication suggested.

Bilateral dermoid ovarian cyst in an adolescent girl.

A 19-year-old unmarried woman with regular menstrual cycles presented with symptoms of vague abdominal pain of 1 month duration. General condition fair. Per abdomen-a firm, non-tender mass corresponding to 26 weeks of gestation with smooth surface, upper and lateral borders well defined, lower border not palpable was observed. Ultrasonography: left ovarian tumour 28×19 cm with mixed echogenicity was seen in the pelvis extending superiorly into the abdominal cavity with fat, fluid contents, multiple septations. Right ovary measures 6×4 cm with 3.7 cm focal hyperechoic lesion. Uterus anteverted, normal size. No free fluid seen. CT confirmed the ultrasonography findings. Cancer antigen (CA) 125 was 52 IU/mL. Exploratory laparotomy followed by left ovariotomy and salpingectomy and right ovarian cystectomy was performed, leaving behind a significant amount of normal ovarian tissue. Cut section of the gross specimen of the left ovarian tumour-dermoid cyst-plenty of sebaceous fluid and a large tuft of hair. The right ovarian cystectomy revealed a dermoid cyst with hair and pellets of sebum. Histopathology showed bilateral dermoid ovarian cyst.