蛇形喉周通气道和喉罩用于儿科患者的随机前瞻性研究

背景蛇形喉周通气道（CobraPLA）在成人正压通气时,密封压力优于单纯喉罩（LMAU）,本研究旨在比较两者在婴儿和儿童中的使用效果。方法200例小儿患者随机分为CobraPLA组和LMAU组,测量套囊充气压力为40和60cmH2O时气道的密封效果,插入的难易度和时间,手术后咽痛、发声困难、喉痉挛、支气管痉挛和胃内胀气的发生率,间断测量CobraPLA端和麻醉呼吸回路Y型接口处的呼气末二氧化碳浓度（ETCO2）。对主要转归指标,各组又分为小型号和大型号CobraPLA及LMAU亚组进行分析。结果以均数±标准差表示,P〈0．05表示有显著性差异。结果套囊充气压为60cmH2O时,大型号CobraPLA亚组的气道密封压力（22±7cmH2O）明显高于小型号CobraPLA亚组（18±5cmH2O）及大型号LMAU亚组（16±5cmH2O）（P〈0．001）;CobraPLA组比LMAU组更不易移位（手术前和手术后的解剖合适度评分相同）,气体入胃也少;CobraPLA头端ETCO,测量值比Y型接口处高6．4±6mmHg。结论从大多数参数分析来看,CobraPLA与LMAU在儿科患者麻醉中的作用相当,某些方面优于后者。     

Prospective, randomized comparison of laryngeal tube and laryngeal mask airway in pediatric patients

BACKGROUND: While reports of the use of laryngeal mask airway (LMA)-Classic in great patient numbers are available, data on the use of the laryngeal tube (LT) in this age group is limited. The two devices are compared in a prospective randomized trial to evaluate success rates and quality of airway seal. METHODS: Sixty children, aged 2-8 years, scheduled for elective surgical interventions were randomized to be ventilated with LMA or LT. Standardized anesthesia was induced with fentanyl and propofol. Number of insertion attempts, time until first tidal volume and intraoperative tidal volumes, and peak pressures were recorded. Airway leak pressure was measured with cuff pressure adjusted to 60 cmH(2)O. RESULTS: Demographic data were comparable, average age in the LMA/LT group was 5.2 +/- 1.9/5.3 +/- 1.9 years. Insertion was successful in 29 of 30 patients in the LMA group (second attempt 8) and in all patients in the LT group (second attempt 3). Time until first tidal volume for LMA/LT was 23.1 +/- 7.3/19.2 +/- 8.6 s (P < 0.05). Peak airway pressures for LMA and LT were 15.3 +/- 3.4 and 17.1 +/- 4.0 cmH(2)O (P < 0.05) with tidal volumes of 10.2 +/- 2.2 and 10.2 +/- 1.9 ml.kg(-1), airway leak pressure was 19.2 +/- 8.6 cmH(2)O for LMA and 26.3 +/- 7.3 cmH(2)O for LT (P < 0.001). CONCLUSION: Insertion success rate is high with both LMA and LT in the age group studied. The airway leak pressure, serving as an estimate to judge quality of airway seal, is higher with the LT.     

A randomised, crossover comparison between the CobraPLA and the LMA Classic in paralysed patients

We performed a randomised, crossover study in 38 anaesthetised and paralysed patients to compare the performance of the CobraPLA and the LMA Classic during controlled ventilation. The median (IQR [range]) airway leak pressure was 23.0 (20-24 [12-30]) cmH(2)O for the CobraPLA and 15.0 (12-19 [8-30]) cmH(2)O for the LMA Classic (p < 0.001). The median (IQR [range]) insertion time was 15.0 (11-26 [9-31]) s for the CobraPLA and 22.5 (20-25 [15-50]) s for the LMA Classic (p < 0.001). There was no significant difference between the two devices for the number of insertion and reposition attempts, the anatomical position scored by fibreoptic bronchoscopy or the peak and plateau airway pressures. There were no adverse events during anaesthesia. The CobraPLA provides a better airway leak pressure and takes less time to insert than the LMA Classic in paralysed patients. Our data show that the CobraPLA can be used to secure a patent airway during controlled ventilation in selected patients.     

Insertion characteristics, sealing pressure and fiberoptic positioning of CobraPLA in children

BACKGROUND: The CobraPLA(TM) is a new supraglottic airway device designed for the use in spontaneously breathing and mechanically ventilated patients. In adults it has been found as effective as the LMA, but with better sealing qualities. The aim of the present study was to evaluate fit and sealing characteristics of CobraPLA size 1.5 and 2 in mechanically ventilated children. METHODS: Forty children, ASA I/II, aged 1-10 years, weighing 10-35 kg were scheduled for minor surgical procedures. The number of attempts for insertion and fiberoptic positioning of the CobraPLA was assessed. After muscle relaxation had been achieved, airway sealing pressure was measured by gradually increasing maximum inspiratory pressure to a maximum of 30 cm H(2)O. RESULTS: Insertion of CobraPLA was successful at the first attempt in 90% of patients. The vocal cords were visualized in 90% of patients (grade 0: 2.5%, grade 1: 7.5%, grade 2: 30%, grade 3: 15%, grade 4: 45%). Median sealing pressure was 20.0 +/- 6.0 cm H(2)O. In 21% of patients gastric insufflation was observed at a peak inspiratory pressure of 20 cm H(2)O or below. CONCLUSIONS: The CobraPLA was found to have easy insertion characteristics and good anatomical fitting in children between 10 and 35 kg. If positive pressure ventilation with CobraPLA size 1.5 and 2.0 is required, peak inspiratory pressure should be kept below the leak pressure and the abdomen closely monitored for signs of gastric insufflation.     

Exposure to anaesthetic trace gases during general anaesthesia: CobraPLA vs. LMA classic

Background: To prospectively investigate the performance, sealing capacity and operating room (OR) staff exposure to waste anaesthetic gases during the use of the Cobra perilaryngeal airway (CobraPLA) compared with the laryngeal mask airway classic (LMA). Methods: Sixty patients were randomly assigned to the CobraPLA or the LMA group. Insertion time, number of insertion attempts and airway leak pressures were assessed after induction of anaesthesia. Occupational exposure to nitrous oxide (N₂O) and Sevoflurane (SEV) was measured at the anaesthetists' breathing zone and the patients' mouth using a photoacoustic infrared spectrometer. Results: N₂O waste gas concentrations differed significantly in the anaesthetist's breathing zone (11.7±7.2 p.p.m. in CobraPLA vs. 4.1±4.3 p.p.m. in LMA, P=0.03), whereas no difference could be shown in SEV concentrations. Correct CobraPLA positioning was possible in 28 out of 30 patients (more than one attempt necessary in five patients). Correct positioning of the LMA classic was possible in all 30 patients (more than one attempt in three patients). Peak airway pressure was higher in the CobraPLA group (16±3 vs. 14±2 cmH₂O, P=0.01). The average leak pressure of the CobraPLA was 24±4 cmH₂O, compared with 20±4 cmH₂O of the LMA classic (P<0.001; all values means±SD). Conclusion: Despite higher airway seal pressures, the CobraPLA caused higher intraoperative N₂O trace concentrations in the anaesthetists' breathing zone.     

Brief review: The Cobra Perilaryngeal Airway (CobraPLA®) and the Streamlined Liner of Pharyngeal Airway (SLIPA™) supraglottic airways

PURPOSE: To summarize the published literature related to two, new supraglottic airways (SGAs): the Cobra Perilaryngeal Airway (CobraPLA) and the Streamlined Liner of Pharyngeal Airway (SLIPA). SOURCE: We identified original articles, through searches on Medline and PubMed, using the keywords 'Cobra', 'CobraPLA', 'Cobra-PLA', 'PLA', and 'SLIPA'. PRINCIPAL FINDINGS: Searches identified 28 publications evaluating the CobraPLA, six of which were randomized, controlled trials. Five publications evaluated the SLIPA, two of which were randomized, controlled trials. Studies compared the CobraPLA with a number of SGAs, in regards to both efficacy and safety. While the CobraPLA is comparable to the laryngeal mask airway (LMA) Classic, with respect to insertion times and the incidence and severity of sore throat, the CobraPLA is superior, with respect to airway sealing pressure, and has been used successfully in patients with limited mouth opening and limited head extension. Insertion times, first insertion success rates, recovery times, and hemodynamic responses, associated with insertion of the SLIPA, are similar to those of the LMA Proseal. Although the SLIPA has a unique reservoir chamber to contain regurgitated fluid, the extent of its protection against pulmonary aspiration has not been established in the clinical setting. CONCLUSION: Both the CobraPLA and the SLIPA are intended for use during short procedures under general anesthesia, and have comparable efficacy and complication rates in comparison to the LMA Classic. Both airways may be considered as primary SGA devices, and the CobraPLA may be also be used as a rescue airway device.     

A comparison between the PLA Cobra and the Laryngeal Mask Airway Unique during spontaneous ventilation: a randomized prospective study

The Laryngeal Mask (LMA) Unique and the Cobra Perilaryngeal Airway (PLA) are single-use supraglottic devices. There are no published studies comparing these devices during spontaneous ventilation. We compared the LMA Unique and the Cobra PLA with respect to 1) ventilatory variables during spontaneous ventilation, 2) time to achieve an effective airway, 3) airway intervention requirements, 4) cuff seal pressures, 5) fiberoptic score, and 6) perioperative adverse events. Eighty adult ASA physical status I-II patients undergoing general anesthesia for minor routine surgery were randomly allocated to LMA Unique or PLA Cobra for airway management. No statistically significant differences were found between the devices with respect to inspiratory tidal volume, expiratory tidal volume, end-tidal CO2 concentration, respiratory rate, number and type of airway interventions required with placement, the fiberoptic score, and the incidence of perioperative adverse events. The oropharyngeal leak (seal) pressure was higher for the CobraPLA (27 +/- 7 versus 21 +/- 4 cm H2O; P < 0.001). The oxygen saturation was higher (98.1% +/- 1% versus 97.3% +/- 2%; P = 0.02) in the LMA group. Time of insertion was shorter for LMA (23.7 +/- 2 s versus 26.6 +/- 7 s; P = 0.02) and insertion difficulty was less for LMA (P = 0.03). As these differences were not judged to be clinically important, both devices appear to be effective in establishing an adequate airway in patients who are spontaneously breathing under general anesthesia.     

Appropriate size of laryngeal mask airway for children

The aim of this crossover study was to determine the optimal size of laryngeal mask airway in children weighing 10 to 20 kg. In each of 67 apnoeic anaesthetized children, the size 2 and size 2 1/2 laryngeal mask airways were inserted consecutively by a skilled user and the cuff inflated to 60 cmH2O. Each LMA was assessed for the ease of insertion (by the number of attempts), oropharyngeal leak pressure, anatomical position (assessed fibreoptically) and the volume of air required to achieve intracuff pressure of 60 cmH2O. During the measurement of oropharyngeal leak pressure, the airway pressure was not allowed to exceed 30 cmH2O. There was no failed attempt at insertion with any size. The oropharyngeal leak pressure was significantly less for the size 2 LMA compared to the size 2 1/2 LMA (P < 0.001). The oesophagus was visible on three occasions, all with the size 2 LMA. Gastric insufflation occurred in three patients, all with the size 2 LMA. The incidence of low oropharyngeal leak pressure (< 10 cmH2O) was low (9.0%) and all occurred with the size 2 LMA. The fibreoptic bronchoscope scores were not significantly different between the two sizes of LMAs. The volume of air to achieve intracuff pressure of 60 cmH2O was much lower than the maximum recommended volume (5.1 ml for size 2 and 6.2 ml for size 2 1/2). We conclude that the size 2 1/2 LMA provides a better fit than size 2 in children 10 to 20 kg.     

The size 1(1/2) ProSeal laryngeal mask airway in infants: a randomized, crossover investigation with the Classic laryngeal mask airway

Many problems with the Classic laryngeal mask airway (CLMA) in infants are believed to be related to its inadequate cuff design. One of the main limitations of the CLMA is that the resulting low-pressure seal can be inadequate for positive pressure ventilation (PPV). The ProSeal LMA (PLMA), a new laryngeal mask airway with a modified cuff, has been shown to form a more effective seal than the CLMA in children. The first infant size PLMA, size 1(1/2), became available recently. We studied 30 anesthetized, nonparalyzed infants aged 15 mo (2-30 mo) and weighing 9 kg (5-12 kg). The CLMA and PLMA were inserted in random order into each patient. Airway leak pressure and maximum tidal volume were measured. Ease of insertion, quality of initial airway, and fiberoptic position were also determined. Gastric tube placement was assessed for the PLMA. The mean airway leak pressure in neutral head position (26.7 versus 18.9 cm H2O), maximum flexion (35.6 versus 28.2 cm H2O), and the mean maximum tidal volume (312 versus 260 mL) were significantly higher for the PLMA (P < 0.01). Air entered the stomach in eight patients with the CLMA but did not with the PLMA. Gastric tube placement was possible in all but one patient. In three patients, the use of the PLMA led to some degree of clinically relevant compression of the larynx. The size 1(1/2) PLMA seems to be a more suitable device for airway maintenance in infants than the same size CLMA. The ability to insert a gastric tube at the same time, and a significantly higher airway leak pressure than with the CLMA, may have important implications for its use for PPV in infants.     

The ProSeal laryngeal mask airway: A randomized, crossover study with the standard laryngeal mask airway in paralyzed, anesthetized patients

BACKGROUND: The ProSeal laryngeal mask airway (PLMA) is a new laryngeal mask device with a modified cuff to improve seal and a drainage tube to provide a channel for regurgitated fluid and gastric tube placement. In the present randomized, crossover study, the authors tested the hypothesis that ease of insertion, airway sealing pressure, and fiberoptic position differ between the PLMA and the standard laryngeal mask airway (LMA). For the PLMA, we also assess ease of gastric tube placement and the efficacy of an introducer tool. METHODS: Sixty paralyzed, anesthetized adult patients were studied. Both devices (only size 4) were inserted into each patient in random order. Airway sealing pressure and fiberoptic position were determined during cuff inflation from 0 to 40 ml in 10-ml increments. Gastric tube insertion was attempted with the PLMA if there was no gas leak from the drainage tube. In 60 additional patients, ease of insertion for the PLMA was compared with and without an introducer. RESULTS: First-time success rates were higher (60 of 60 vs. 52 of 60; P = 0.003) and the effective airway time shorter (9 +/- 3 s vs20 +/- 18 s; P < 0.0001) for the LMA. There were no failed uses of either device within three attempts. Airway sealing pressure was 8-11 cm H2O higher for the PLMA at all cuff volumes (P < 0.00001) and was higher in females for both devices. Fiberoptic position was better with the LMA at all cuff volumes (P < 0.00001), but vocal cord visibility was similar (LMA, 59 of 60; PLMA, 56 of 60). For the PLMA, gastric tube placement was successful in 58 of 58 patients and took 9 +/- 5 s. First-time success rates were higher (59 of 60 vs53/60; P = 0.03) and the effective airway time shorter (15 +/- 13 s vs 23 +/- 18 s; P = 0.008) with the introducer. CONCLUSION: The PLMA is capable of achieving a more effective seal than the LMA and facilitates gastric tube placement, but it is more difficult to insert unless an introducer tool is used. When correctly positioned, the PLMA isolates the glottis from the upper esophagus with possible implications for airway protection.     

Comparison of laryngeal mask airway (LMA)-Proseal™ and the LMA-Classic™ in ventilated children receiving neuromuscular blockade

PURPOSE: To determine whether a functional difference exists between the size 2 laryngeal mask airway (LMA)-Classic (CLMA) and LMA-Proseal (PLMA) in anesthetized children who have received neuromuscular blockade. Airway leak during intermittent positive pressure ventilation (IPPV) and adequacy of fibreoptic laryngeal view were the primary study outcomes. METHODS: A randomized, controlled, single-blinded study of 51 ASA I or II children weighing 10-20 kg was undertaken. The anesthetic technique was standardized. Following insertion of the LMA and cuff inflation to 60 cm H(2)O, we measured oropharyngeal leak pressure and gastric insufflation and leak fraction during IPPV, and evaluated the adequacy of fibreoptic view. RESULTS: Oropharyngeal leak pressure measured by neck auscultation was higher for the PLMA compared to the CLMA (23.7 vs 16.5 cm H(2)O, P = 0.009) but, when measured by the inspiratory hold maneuver was not significantly different (24.8 vs 20.3 cm H(2)O, respectively, P = 0.217). Leak fraction values were similar for the CLMA and the PLMA (21.2%. vs 13.3%, respectively, P = 0.473). A satisfactory view of the larynx was obtained more frequently in the PLMA group (21/25 vs 10/25, P = 0.003). Gastric insufflation during leak determination was more common with the CLMA (12/26 vs 2/25 CLMA vs PLMA, respectively, P = 0.006). CONCLUSION: In children undergoing IPPV with neuromuscular blockade, the size 2 PLMA is associated with a higher leak pressure by auscultation and less gastric insufflation compared to the CLMA. Leak pressures assessed by manometric stability are similar with these two devices. The improved fibreoptic view of the larynx through the PLMA may be advantageous for bronchoscopy.     

Comparison of the laryngeal mask (LMA) and laryngeal tube (LT) with the perilaryngeal airway (cobraPLA) in brief paediatric surgical procedures

We compared the laryngeal mask airway (LMA) and the laryngeal tube (LT) with the perilaryngeal airway (CobraPLA, PLA) in anaesthetised, paralysed children having brief surgical procedures. After obtaining informed consent, 90 paediatric ASA Status 1 and 2 patients awaiting short surgical procedures were randomised to have their airways managed with an LMA, LT or PLA. Anaesthesia was induced with sevoflurane (2.5 to 4%) and muscle paralysis with mivacurium (0.2 mg/kg intravenously). The number of insertion attempts, time taken to insert the device, haemodynamic responses to insertion (mean arterial blood pressure, heart rate, pulse oximetry and end-tidal CO2), clinical performance and occurrence of postoperative sore throat were recorded. When the airway device was removed, it was examined for visible blood. Patients and parents were asked about the occurrence of sore throat, dysphonia and dysphagia 24 hours postoperatively. Heart rate, mean arterial blood pressure, pulse oximetry and end tidal CO2 did not differ among the groups. Insertion times for the devices were similar (LMA: 19+/-11 seconds, LT 21+/-12 seconds, PLA: 18+/-12 seconds), as were the rates of successful insertion at first attempt (LMA 66.7%; LT 70.0%; PLA 73.3%). The number and type of airway interventions to achieve an effective airway were comparable. When the airways were removed, positive blood traces were noted on 20% of the LMAs, 20% of the PLAs and 10% of the LTs. Haemodynamic, ventilation and oxygenation variables throughout the surgery were similar with LMA, LT and PLA and there were no significant differences in insertion time or signs or symptoms of mucosal trauma when these devices were used in paralysed children.     

A comparison of the laryngeal tube with the laryngeal mask airway during routine surgical procedures

The laryngeal mask airway (LMA; Laryngeal Mask Company, Henley-on-Thames, UK) is an established airway device, whereas the laryngeal tube (LT) is relatively new and therefore not as well investigated. Therefore, the purpose of the present prospective, randomized, controlled trial was to compare the LT with the LMA in routine clinical practice. In 50 patients undergoing general anesthesia for minor routine surgery, standardized anesthesia was induced and maintained with alfentanil and propofol. Patients were randomized to controlled ventilation (fraction of inspired oxygen = 0.4; fraction of inspired nitrous oxide = 0.6; tidal volume = 7 mL/kg; respiratory rate = 10 breaths/min) with the LT (n = 25) or the LMA (n = 25). Oxygen saturation was recorded before the induction of anesthesia and after the administration of oxygen. After 2 and 10 min of ventilation with the LT or LMA, oxygen saturation, end-expiratory carbon dioxide, expiratory tidal volume, and peak airway pressure were recorded. Capillary blood gas samples were taken before the induction of anesthesia and after 10 min of ventilation. Time of insertion and airway leak pressure of each device were measured. The time of insertion was comparable with both devices (LT versus LMA, median 21 s versus 19 s; P = not significant). Blood gas samples and ventilation variables revealed sufficient ventilation and oxygenation with either device (P = not significant). Peak airway pressure (LT, 17 +/- 3 cm H(2)O; LMA, 15 +/- 3 cm H(2)O) and airway leak pressure (LT, 36 +/- 3 cm H(2)O; LMA, 22 +/- 3 cm H(2)O) were significantly (P < 0.05) higher when using the LT compared with the LMA. In conclusion, using the LT and LMA resulted in comparable ventilation and oxygenation variables in this model of ASA physical status I and II patients undergoing routine surgical procedures. The newly developed LT may be a simple alternative device to secure the airway. IMPLICATIONS: The laryngeal tube, a newly developed airway device, and the laryngeal mask airway were used to ventilate patients in the operating room. Both airway devices proved to be effective and safe; however, the laryngeal tube allowed greater airway pressure during ventilation.     

A randomized crossover comparison of the size 2 1/2 laryngeal mask airway ProSeal versus laryngeal mask airway-Classic in pediatric patients

The laryngeal mask airway (LMA)-ProSeal (P-LMA) forms a more effective seal than the LMA-Classic (C-LMA) and facilitates gastric tube (g-tube) placement in adults. The first pediatric sizes of P-LMA recently became available. In 30 anesthetized, nonparalyzed children, aged 7.7 +/- 2 yr and weighing 27 (20-35) kg, we inserted the size (1/2) P-LMA and C-LMA in random order. Ease of insertion, quality of initial airway, fiberoptic position, airway leak pressure, and maximum tidal volume were determined. G-tube placement was assessed for the P-LMA. Ease of insertion was similar for both devices. The quality of the initial airway was better for the P-LMA (P = 0.01). Airway leak pressure in neutral head position (22.6 versus 18.5 mbar; P = 0.003), maximum flexion (37 versus 26.3 mbar; P < 0.001), maximum extension (15.2 versus 13 mbar; P = 0.045), and maximum tidal volume (1088 versus 949 mL; P = 0.002) were significantly better for the P-LMA. Air entry into the stomach occurred with the C-LMA but not with the P-LMA (P = 0.014). G-tube placement was possible in all patients. The reliability of g-tube placement and the significantly increased airway leak pressure found in this investigation might have important implications for use of the size (1/2) P-LMA for positive pressure ventilation in children.     

Crossover comparison of airway sealing pressures of 1.5 and 2 size LMA-ProSeal™ and LMA-Classic™ in children, measured with the manometric stability test

Objectives: To compare airway sealing pressures, air leak, optimal positioning of the LMA‐ProSeal? and LMA‐Classic? in children. Methods: A crossover, randomized study was conducted in children aged 6 months–7 years weighing <20 kg scheduled for minor elective surgery under GA with sevoflurane. Either a 1.5 or 2‐size LMA‐ProSeal? or LMA‐Classic? was inserted first. Optimal position of the devices was evaluated by fiberoptic bronchoscopy (FOB). Airway sealing pressures were determined under standardized conditions by the manometric stability test at the proximal end of the LMA device. Gas leak observed by auscultation over the neck and epigastrium was noted at these pressures. Results: Twenty‐seven children of mean ages 29.48 ± 19.81 months and mean weight 11.23 ± 3.28 kg were included for evaluation. Airway sealing pressures were noted to be similar: 23.11 ± 8.28 cm H₂O with LMA‐ProSeal? and 23.26 ± 8.21 cm H₂O with LMA‐Classic?. At these sealing pressures, air leak in the neck was observed in 21/27 children with LMA‐ProSeal? compared with 24/27 with LMA‐Classic? (P = 0.467). Optimal device positioning as viewed by FOB was seen in 14/27(51.8%) children with LMA‐ProSeal? and 15/27(55.6%) with LMA‐Classic?. Airway sealing pressures with suboptimal position of LMA‐ProSeal? was 22.23 ± 10.23 cm H₂O and with optimal position 23.93 ± 6.25 cm H₂O (P = 0.612). Conclusion: The LMA‐ProSeal? and LMA‐Classic? size 1.5 and 2 provide similar mean airway sealing pressures as assessed by the manometric stability test under standardized conditions, with similar air leak and optimal positioning.     

Vergleich von zwei Larynxmaskenmodellen zur Atemwegssicherung bei Patienten mit Immobilisation der Halswirbelsäule

BACKGROUND: Reduced cervical spine mobility can impair laryngoscopy and tracheal intubation. Supraglottic airway devices can be important alternatives for oxygenation under these circumstances. The Ambu laryngeal mask (ALM) and the LMA-Classic (LMA) are compared in patients with immobilization of the cervical spine.METHODS: In 60 patients scheduled for elective ambulatory interventions, ALM or LMA were inserted after cervical immobilization with an extrication collar and assessment of laryngoscopic view. Insertion time (removal of facemask until first tidal volume), number of insertion attempts, airway leak pressure (cuff pressure 60 cm H(2)O), intraoperative complications and postoperative complaints were assessed.RESULTS: Demographical data, insertion attempts, insertion time (ALM 15.6+/-4.4 s, LMA 15.5+/-4.9 s) and airway leak pressure (ALM 25.6+/-5.2 cm H(2)O, LMA 26.5+/-6.5 cm H(2)O) were comparable. Traces of blood were found in 6 LMAs and 3 ALMs after removal, mild trouble with swallowing (visual analogue scale, VAS 2-4) in the recovery room and after 24 h were complaints by 1 ALM and 2 LMA patients.CONCLUSIONS: LMA-Classic and Ambu laryngeal masks are suitable for rapid and reliable airway management in patients with cervical immobilization.     

i-gel喉罩用于妇科腹腔镜手术患者气道管理的效果

目的 评价i-gel喉罩用于妇科腹腔镜手术患者气道管理的效果.方法 择期全麻下拟行妇科腹腔镜手术患者60例,ASA分级Ⅰ或Ⅱ级,年龄21～64岁,体重45～90 kg,Mallampatti分级Ⅰ～Ⅲ级,采用随机数字表法,将其随机分为2组(n=30):i-gel喉罩组(I组)和Supreme喉罩组(S组).根据体重选择喉罩型号,麻醉诱导后置入喉罩,经引流管放置胃管,行机械通气.记录喉罩置入时间、置入次数、胃管置入次数、喉罩密封压、纤维支气管镜检查分级、术中血液动力学指标、通气指标、麻醉时间和苏醒时间,记录拔除喉罩后咽喉痛、吞咽痛和声音嘶哑的发生情况.结果 两组麻醉时间、苏醒时间、喉罩置入时间、纤维支气管镜检查分级、术中血液动力学指标和通气指标差异无统计学意义(P>0.05).两组喉罩和胃管置入成功率均为100%.与S组比较,I组喉罩密封压升高,咽喉痛和吞咽痛发生率降低(P<0.05或0.01).结论 i-gel喉罩气道密封性可靠,并发症少,可安全有效地应用于妇科腹腔镜手术患者的气道管理.

Abstract：

Objective To assess the efficacy of laryngeal mask airway (LMA) i-gel used in patients undergoing laparoscopic gynecological surgery. Methods Sixty ASA Ⅰ or Ⅱ patients, aged 21-64 yr, weighing 4590 kg, undergoing elective laparoscopic gynecological surgery, were randomized into 2 groups ( n = 30 each):LMA i-gel group (group Ⅰ) and LMA Supreme group (group S) . Mallampatti test was performed before operation in both groups. Anesthesia was induced with target-controlled infusion of propofol (target plasma concentration 2.5-4.0 μg/ml) and remifentanil (target plasma concentration 3-6 ng/ml) . After the patients lost consciousness, rocuronium 0.6 mg/kg was given to facilitate the LMA insertion. LMA i-gel and LMA Supreme were inserted in I and S groups respectively. A gastric tube was inserted through the drain tube of the LMA. In group S the air was injected into the cuff to make intracuff pressure reach 60 cm H2O after successful LMA insertion. The LMA placement time, the number of attempts of LMA insertion, the number of attempts of gastric tube placement, the airway sealing pressure, the parameters of hemodynamics and ventilation, and complications (sore throat, odynopliagia,hoarseness) were recorded. The fiberoptic laryngoscopy scores were assessed after successful LMA placement. The anesthesia time and recovery time were also recorded. Results There was no significant difference in the anesthesia time, recovery time, LMA placement time, fiberoptic bronchoscopy scores and the parameters of hemodynamics and ventilation between the two group. The success rates of LMA and gastric tube placement were 100% in both groups. The airway sealing pressure was significantly higher, while the incidence of sore throat and odynopliagia was significantly lower in group I than in group S. Conclusion LMA i-gel provides adequate ventilation during operation with fewer complications and can be used effectively for gynecological laparoscopic surgery.     

Initial experience of the i-gel supraglottic airway by the residents in pediatric patients

Purpose

Insertion of a laryngeal mask airway (LMA) is occasionally difficult in children because of their anatomical features and variations. A new single-use supraglottic airway device, the i-gel airway, was recently introduced. The objective of this study was to show the initial experience of the i-gel airway device by the residents for pediatric patients.

Methods

With approval from the local ethics committee and parental informed consent, 70 children undergoing minor surgery in the supine position, ASA score I?CII, were investigated. Exclusion included patients having thoracic, neurosurgical, spine, and otolaryngological procedures. Patients were divided into three groups: group 1 was airway size 1.5 for patients weighing 5?C12?kg, group 2 was size 2 for 10?C25?kg, and group 3 was size 2.5 for those weighing 25?C35?kg. The following seven characteristics were evaluated: (1) ease of the i-gel and gastric tube insertion; (2) leak pressure; (3) tidal volume/body weight at leak pressure point; (4) fiberscope score; (5) insertion time; (6) hypoxia rate (laryngospasm); and (7) coughing and trace of bleeding.

Results

The overall insertion success rate and the success rate at first attempt were 99% and 94%, respectively. Gastric tube insertions were easy in all patients. The overall leak pressure was 23?±?5?cmH₂O. The tidal volume per body weight was 24?±?10?ml/kg. A good view of the fiberscope was achieved in 79%. In group 1 (size 1.5), one failed insertion, two dislocations, and one dysphonia were observed. Hypoxia rate was 1%. There was no case with coughing and trace of bleeding.

Conclusion

These results show that the i-gel airway is a safe and effective device for use by residents who do not have experience with insertion of a pediatric LMA. However, using size 1.5, special caution should be taken to protect the infant airway, similar to what has been previously reported for other airway devices.     

Comparison of the laryngeal mask (LMA) and laryngeal tube (LT) with the new perilaryngeal airway (CobraPLA) in short surgical procedures

BACKGROUND AND OBJECTIVE: We compared the laryngeal mask airway (LMA) and the laryngeal tube (LT) with the newly introduced perilaryngeal airway (CobraPLA, PLA) with regard to haemodynamic responses induced by airway insertion, clinical performance and occurrence of postoperative sore throat after short surgical procedures. METHODS: After premedication, 90 ASA I-II patients awaiting short surgical procedures were randomized to receive, LMA, LT or PLA. Anaesthesia was induced with intravenous propofol (2.5 mg kg(-1)) and mivacurium (0.2 mg kg(-1)). Number of attempts, time of insertion of the device, any other unwanted effect, mean aterial pressure, heart rate, oxygen saturation and end-tidal carbon dioxide were recorded. At the end of surgery, the cuff of the device was immediately deflated and the airway device was removed. The device was examined and noted for the presence of visible blood. Patients were asked to rate their throat soreness, dysphonia and dysphagia 1 and 24 h postoperatively. RESULTS: There were no differences in haemodynamic variables. Insertion times for the devices were similar (LMA: 20 +/- 11 s, LT: 19 +/- 14 s and PLA: 21 +/- 12 s.) The success rates at first insertion were lower in the (LMA group (57%) when compared with the PLA (97%, P < 0.05). The number and type of airway interventions for achieving an effective airway were similar. When the airways were removed 50% of the PLA devices had positive blood traces, while only 17% of the LMA and LT devices had positive blood traces (P < 0.01). Fifty percent of the patients suffered from a sore throat in the PLA group, which was significantly higher than in the LMA and LT groups (P < 0.05). CONCLUSION: We conclude that haemodynamic, ventilation and oxygenation variables throughout the surgery were similar with, LMA, LT and PLA, but LT and PLA were easier to insert; LMA and LT caused less mucosal trauma.     

Gum-elastic bougie-guided insertion of the ProSeal laryngeal mask airway: a new technique

We determined the success rates, cardiovascular responses and airway morbidity for gum-elastic bougie-guided insertion of the ProSeal laryngeal mask airway. One hundred anaesthetized, non-paralyzed adults (ASA 1-2 aged 18 to 80 years) were studied. The ProSeal LMA drainage tube was primed with a well-lubricated 16 French gauge gum-elastic bougie with the curved end proximal and the straight end protruding 30 cm beyond the drainage tube tip. The straight end of the gum-elastic bougie was inserted into the oesophagus under laryngoscopic guidance, the laryngoscope removed and the ProSeal LMA inserted using the standard insertion technique and the gum-elastic bougie as a guide. The following variables were recorded: ease of insertion, oropharyngeal leak pressure, ventilatory capability, ease of gastric tube insertion, blood staining on the bougie or LMA at removal, and postoperative airway morbidity. Haemodynamic data were recorded immediately pre-insertion and every minute for five minutes after insertion. Gum-elastic bougie and ProSeal LMA insertion was successful at the first attempt in all patients within 50 seconds. There were no significant increases in heart rate or blood pressure. Oropharyngeal leak pressure was 33 (17-40) cmH2O and ventilation was possible without leak in all patients at 9.5 ml x kg(-1) tidal volume. There were no drainage tube or gastric air leaks. Gastric tube insertion was successful at the first attempt in all patients. Blood staining at removal was not detected on the gum-elastic bougie, but was detected in 3% of ProSeal LMAs. The incidence of sore throat, dysphagia and dysarthria was 21%, 9% and 1% respectively. We conclude that gum-elastic bougie-guided insertion of the ProSeal LMA has a high success rate and is associated with minimal haemodynamic change and a low incidence of trauma.