Evaluation of the revised laryngeal tube suction: the laryngeal tube suction II in 100 patients

Effectiveness of Proseal laryngeal mask airway and laryngeal tube suction in elective non-laparoscopic surgeries of up to ninety minutes duration: A prospective, randomized study

Background and Aims:

Proseal laryngeal mask airway (LMA) and laryngeal tube suction (LTS) are both supraglottic devices with an esophageal suction port. In the present prospective, randomized study, the effectiveness of airway seal, hemodynamic variables, ability to pass orogastric tube, and postoperative complications with the two devices were evaluated.

Material and Methods:

This was a prospective, randomized, single-blind study conducted in a hospital-based setting. Sixty patients (American Society of Anesthesiologists Grade I and II) undergoing elective general surgery were randomly allocated to Group A (Proseal LMA) or Group B (LTS), and airway seal pressure (primary outcome), peak pressure, hemodynamic parameters (blood pressure, pulse rate and pulse oximetry) during and 5 min after insertion, insertion time, ease of insertion, and postoperative complications (sore throat and hoarseness of voice for a period of 24 hours) (secondary outcomes) were noted. The quantitative data was summarized as mean and standard deviation, and analyzed using Student's t-test. All the qualitative data were summarized as proportions and analyzed using Chi-square test. The levels of significance and α-error were kept 95% and 5%, respectively, for all statistical analyses. P ≤ 0.05 was considered significant (S).

Results:

Proseal LMA had shorter insertion time (16.4 ± 5.6 vs. 20.0 ± 3.9 s), higher seal pressure (27.6 ± 4.6 vs. 24.1 ± 5.6 cm of H₂O), lesser peak pressure (16.3 ± 2.3 vs. 18.5 ± 3.9 cm of H₂O), higher success rate of orogastric tube passage (86.7 vs. 76.7%), and lesser postoperative sore throat (3.3 vs. 10%).

Conclusions:

Both Proseal LMA and LTS were acceptable alternatives for airway management in elective surgeries with controlled ventilation, but the quality of ventilation was found to be significantly better with Proseal LMA (in terms of higher seal pressure, lesser peak pressure, lesser insertion time, and lesser complications).

A comparison between the Supreme laryngeal mask airway and the laryngeal tube suction during spontaneous ventilation: A randomized prospective study

BACKGROUND AND AIMS

The Supreme laryngeal mask airway (SLMA) and the laryngeal tube suction-disposable (LTS-D), both second-generation supraglottic airway devices, have a record of efficiency when used for airway management in mechanically ventilated patients, during general anesthesia. There is no published data comparing these two devices in patients breathing spontaneously during general anesthesia.

MATERIAL AND METHODS

Eighty patients with normal airways undergoing elective general anesthesia with spontaneous ventilation were randomized to airway management with a SLMA or LTS-D. Efficacy and adequacy of oxygenation and ventilation were compared.

RESULTS

No cases of desaturation of oxygen saturation (SpO2) values of less than 95% occurred with either device. The mean difference for SpO2 between the two devices (0.7%) has no clinical significance. Slight hypercapnia was noted with both devices to acceptable values during spontaneous ventilation.

CONCLUSIONS

Both SLMA and LTS-D are suitable and effective for airway management in patients breathing spontaneously during general anesthesia for minor surgery of short duration.

Comparison of laryngeal tube suction II and proseal LMA™ in pediatric patients, undergoing elective surgery

BACKGROUND

Supraglottic airway devices now have an established place in pediatric anesthesia practice. The laryngeal tube suction (LTS) II, a recent revision of the LTS, has very few studies evaluating its use in pediatric patients. The aim of this study was to compare insertion and ventilation profiles of the LTS-II size 2 and the ProSeal™ Laryngeal Mask Airway (PLMA) size 2 in pediatric patients undergoing elective surgeries.

MATERIALS AND METHODS

A randomized prospective study was conducted in 100 children aged 2-5 years between 12 and 25 kg weight, of the American Society of Anesthesiologists physical status I and II scheduled for routine elective surgeries of <90 min duration. They were randomly divided into two groups of 50 each, depending on the device inserted, and a standard protocol for anesthesia was followed. Outcome measures were studied in terms of ease and time of insertion, oxygen saturation (SpO2), oropharyngeal seal pressure (OSP), and ventilation failures.

RESULTS

Both groups were well matched in terms of age, weight, and type of surgery. The success rate for the first attempt was 90% for both the LTS-II group and PLMA group. Insertion was found to be easy in the majority of cases in both groups, and there was no statistical difference in blood pressure, heart rate, or SpO2 on insertion. However, the OSP was significantly more in LTS-II and PLMA (P < 0.001). There were no clinically important complications in the postoperative period.

CONCLUSIONS

Pediatric size 2 LTS-II is easy to insert and provides higher OSP compared with same size PLMA in anesthetized and paralyzed children undergoing elective surgery. It is a safe alternative to PLMA in short duration elective surgeries and may be a better device as it provides for higher OSPs.

A preliminary assessment of the LMA protector™ in non-paralysed patients

BACKGROUND

The LMA Protector™ is the latest CE marked single use supraglottic airway device. This airway device provides access and functional separation of the respiratory and digestive tracts. There are two ports (male, female ports) to provide suction in the laryngeal region and insertion of the gastric tube. The aim of our study is to assess the ease of use, airway quality, device positioning, airway leak and complications associated with initial clinical experience in LMA Protector™ usage.

METHODS

This is an initial investigation of LMA Protector™ airway device. We conducted a preliminary assessment in the anaesthetised women who underwent minor gynaecological procedures with spontaneous ventilation in order to evaluate the performance of the airway device.

RESULTS

Insertion was successful on first and second attempts in 23 (88.5%) and 3 (11.5%) respectively. Median [IQR (range)] insertion time was 19 [17-21(14-58)] seconds. Airway leak pressure was 25.5 [23-29(21-30] cmH₂O. On fibreoptic examination via the device, vocal cords were visible in all 26 patients. There were no alternative airway use or airway manipulations required during maintenance of anaesthesia. Six patients had sore throat 24 h after procedures and there was no dysphagia or hoarseness.

CONCLUSION

This pilot study of the LMA protector shows that the device is easily inserted with fast insertion time, providing a reliable and adequate airway seal.

TRIAL REGISTRATION

Clinicaltrials.gov Registration NCT02531256 . Retrospectively registered on August 21, 2015.

Evaluation of the optimal cuff volume and cuff pressure of the revised laryngeal tube "LTS-D" in surgical patients

Background

Recent case reports have indicated significant cuff overinflation when using the standard filling volume based on the manufacturer’s recommendations in older models of laryngeal tubes. The aim of this study was to determine the minimum cuff pressure needed to perform standardized ventilation without leakage in the new, revised model of the laryngeal tube “LTS-D”.

Methods

After ethical approval, LTS-D was placed for ventilation in 60 anesthetized patients. The cuff was inflated to the recommended volume (#3: 60 ml, #4: 80 ml, and #5: 90 ml). After evaluation of the initial cuff pressure (CP), the CP was lowered in 10 cmH₂O steps until a minimal cuff pressure of 30 cmH₂O was achieved. The absence of an audible leak was required for a step-by-step reduction in the CP. Evacuated cuff volume, success rate, and airway injuries were documented. Data were expressed as medians (interquartile ranges [IQRs]). The comparison of CPs and cuff volumes was performed using the Mann-Whitney test.

Results

After initial inflation, the CP ranged from 105 cmH₂O [90–120; #5] to 120 cmH₂O [110–120; #3]. Lowering the CP to 60 cmH₂O resulted in a reduced cuff volume ranging from 47 ml [44–54; #3] to 77 ml [75–82; #5] compared to the initial inflation (p < 0.001). Leakage occurred more frequently when the CP was lowered to 40 cmH₂O compared to the initial inflation (44/54 [81%]; p < 0.01). Using a CP between 50 cmH₂O and 60 cmH₂O, a leakage rate of 3/54 (5%) was observed, compared to a rate of 11/54 (21%) when using a CP lower than 50 cmH₂O. The overall success rate was 90%, and airway injury occurred in 7% of patients (4/60).

Conclusion

We found significant overinflation of the revised LTS-D using the recommended volume for initial cuff inflation. A CP of 60 cmH₂O was found to be sufficient for ventilation in the majority of patients evaluated. Checking and adjusting the CP in laryngeal tubes is mandatory to avoid overinflation.

Trial registration

ClinicalTrials.gov NCT02300337. Registered: 20 November 2014.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-017-0308-4) contains supplementary material, which is available to authorized users.

All India Difficult Airway Association 2016 guidelines for the management of unanticipated difficult tracheal intubation in adults

The All India Difficult Airway Association (AIDAA) guidelines for management of the unanticipated difficult airway in adults provide a structured, stepwise approach to manage unanticipated difficulty during tracheal intubation in adults. They have been developed based on the available evidence; wherever robust evidence was lacking, or to suit the needs and situation in India, recommendations were arrived at by consensus opinion of airway experts, incorporating the responses to a questionnaire sent to members of the AIDAA and the Indian Society of Anaesthesiologists. We recommend optimum pre-oxygenation and nasal insufflation of 15 L/min oxygen during apnoea in all patients, and calling for help if the initial attempt at intubation is unsuccessful. Transnasal humidified rapid insufflations of oxygen at 70 L/min (transnasal humidified rapid insufflation ventilatory exchange) should be used when available. We recommend no more than three attempts at tracheal intubation and two attempts at supraglottic airway device (SAD) insertion if intubation fails, provided oxygen saturation remains ≥ 95%. Intubation should be confirmed by capnography. Blind tracheal intubation through the SAD is not recommended. If SAD insertion fails, one final attempt at mask ventilation should be tried after ensuring neuromuscular blockade using the optimal technique for mask ventilation. Failure to intubate the trachea as well as an inability to ventilate the lungs by face mask and SAD constitutes 'complete ventilation failure', and emergency cricothyroidotomy should be performed. Patient counselling, documentation and standard reporting of the airway difficulty using a 'difficult airway alert form' must be done. In addition, the AIDAA provides suggestions for the contents of a difficult airway cart.

Laryngeal tube suction II or endotracheal intubation for laparoscopic radical prostatectomy in a head down position: A randomised controlled trial

BACKGROUND

The laryngeal tube suction II (LTS II) is a supraglottic airway device (SAD) with a gastric drainage tube and enhanced seal properties as compared with other SADs. Therefore, its use has been proposed in situations with an elevated risk of aspiration.

OBJECTIVES

To compare the safety and efficacy of airway management and controlled mechanical ventilation when using either an LTS II or an endotracheal tube for laparoscopic radical prostatectomy.

DESIGN

Randomised, controlled, blinded and single-centre study.

SETTING

Academic tertiary care centre in Leipzig from April 2014 to May 2015.

PATIENTS

It was planned to include 100 patients but the study was stopped after 50 patients following an interim analysis. These 50 patients were randomised to either the LTS II group or the endotracheal tube group. All male patients aged more than 18 years for elective laparoscopic radical prostatectomy were eligible. Exclusion criteria included a BMI more than 30, American Society of Anesthesiologists class III or greater, a history of gastroesophageal reflux or other factors known to increase the risk of aspiration and a known difficult airway.

INTERVENTIONS

All patients received general anaesthesia. Airway management was with either a LTS II or an endotracheal tube, according to the randomisation.

MAIN OUTCOME MEASURES

The primary endpoint was successful insertion of the particular airway device during anaesthesia for laparoscopic radical prostatectomy.

RESULTS

In 15 of the 28 patients randomised to LTS II, the device had to be removed and an endotracheal tube inserted, mainly because of an airway leak (n = 10) or swelling of the tongue (n = 3). Ventilation was successful in all patients (n = 22) randomised to endotracheal tube. Quality of ventilation was rated better in the endotracheal tube group.

CONCLUSION

Our data suggest that LTS II should not be the preferred method of airway management in patients undergoing laparoscopic radical prostatectomy.

TRIAL REGISTRATION

DRKS00008985 (German Clinical Trials Register).

A randomized prospective controlled trial comparing the laryngeal tube suction disposable and the supreme laryngeal mask airway: the influence of head and neck position on oropharyngeal seal pressure

BACKGROUND

The Laryngeal Tube Suction Disposable (LTS-D) and the Supreme Laryngeal Mask Airway (SLMA) are second generation supraglottic airway devices (SADs) with an added channel to allow gastric drainage. We studied the efficacy of these devices when using pressure controlled mechanical ventilation during general anesthesia for short and medium duration surgical procedures and compared the oropharyngeal seal pressure in different head and-neck positions.

METHODS

Eighty patients in each group had either LTS-D or SLMA for airway management. The patients were recruited in two different institutions. Primary outcome variables were the oropharyngeal seal pressures in neutral, flexion, extension, right and left head-neck position. Secondary outcome variables were time to achieve an effective airway, ease of insertion, number of attempts, maneuvers necessary during insertion, ventilatory parameters, success of gastric tube insertion and incidence of complications.

RESULTS

The oropharyngeal seal pressure achieved with the LTS-D was higher than the SLMA in, (extension (p=0.0150) and right position (p=0.0268 at 60 cm H2O intracuff pressures and nearly significant in neutral position (p = 0.0571). The oropharyngeal seal pressure was significantly higher with the LTS-D during neck extension as compared to SLMA (p= 0.015). Similar oropharyngeal seal pressures were detected in all other positions with each device. The secondary outcomes were comparable between both groups. Patients ventilated with LTS-D had higher incidence of sore throat (p = 0.527). No major complications occurred.

CONCLUSIONS

Better oropharyngeal seal pressure was achieved with the LTS-D in head-neck right and extension positions , although it did not appear to have significance in alteration of management using pressure control mechanical ventilation in neutral position. The fiberoptic view was better with the SLMA. The post-operative sore throat incidence was higher in the LTS-D.

TRIAL REGISTRATION

ClinicalTrials.gov ID: NCT02856672 , Unique Protocol ID:BnaiZionMC-16-LG-001, Registered: August 2016.

Insertion Success of the Laryngeal Tube in Emergency Airway Management

Background. Emergency airway management (AM) is a priority when resuscitating critically ill or severely injured patients. The goal of this study was to determine the success rates of LT insertion during AM. Methods. Studies that included LT first-pass insertion (FPI) and overall-pass insertion (OPI) success by emergency medical services and in-hospital providers performing AM for emergency situations as well as for scheduled surgery published until July 2014 were searched systematically in Medline. Results. Data of 36 studies (n = 1,897) reported a LT FPI success by physicians of 82.5% with an OPI success of 93.6% (p < 0.001). A cumulative analysis of all 53 studies (n = 3,600) led to FPI and OPI success of 80.1% and 92.6% (p < 0.001), respectively. The results of 26 studies (n = 2,159) comparing the LT with the laryngeal mask airway (LMA) demonstrated a FPI success of 77.0 versus 78.7% (p = 0.36) and an OPI success of 92.2 versus 97.7% (p < 0.001). Conclusion. LT insertion failed in the first attempt in one out of five patients, with an overall failure rate in one out of 14 patients. When compared with the LT, the LMA had a cumulative 5.5% better OPI success rate.

Difficult Airway Society 2015 guidelines for management of unanticipated difficult intubation in adults

These guidelines provide a strategy to manage unanticipated difficulty with tracheal intubation. They are founded on published evidence. Where evidence is lacking, they have been directed by feedback from members of the Difficult Airway Society and based on expert opinion. These guidelines have been informed by advances in the understanding of crisis management; they emphasize the recognition and declaration of difficulty during airway management. A simplified, single algorithm now covers unanticipated difficulties in both routine intubation and rapid sequence induction. Planning for failed intubation should form part of the pre-induction briefing, particularly for urgent surgery. Emphasis is placed on assessment, preparation, positioning, preoxygenation, maintenance of oxygenation, and minimizing trauma from airway interventions. It is recommended that the number of airway interventions are limited, and blind techniques using a bougie or through supraglottic airway devices have been superseded by video- or fibre-optically guided intubation. If tracheal intubation fails, supraglottic airway devices are recommended to provide a route for oxygenation while reviewing how to proceed. Second-generation devices have advantages and are recommended. When both tracheal intubation and supraglottic airway device insertion have failed, waking the patient is the default option. If at this stage, face-mask oxygenation is impossible in the presence of muscle relaxation, cricothyroidotomy should follow immediately. Scalpel cricothyroidotomy is recommended as the preferred rescue technique and should be practised by all anaesthetists. The plans outlined are designed to be simple and easy to follow. They should be regularly rehearsed and made familiar to the whole theatre team.

The novel intubating laryngeal tube (iLTS-D) is comparable to the intubating laryngeal mask (Fastrach) - a prospective randomised manikin study

Background

Supraglottic devices are helpful for inexperienced providers who perform ventilation in emergency situations. Most supraglottic devices do not allow secondary tracheal intubation through the device. The novel intubating laryngeal tube (iLTS-D®) and the intubating laryngeal mask (Fastrach™) are devices that offer supraglottic ventilation and secondary tracheal intubation.

Methods

We evaluated the novel iLTS-D and compared it to the established Fastrach using a manikin-based study. Participants used both devices in a randomised order. The participants conducted four consecutive trials on a manikin. One trial was composed of the following procedures. First, participants ventilated the manikin using either iLTS-D or Fastrach. ‘Time to ventilation’, success rates and number of attempts were recorded for the supraglottic device. Second, participants intubated the manikin through the previously inserted supraglottic device. ‘Time to tracheal ventilation’, success rate and tube localisation were recorded. The primary endpoint was the results of the final fourth trial, which mirrored the standardised training of trials 1, 2 and 3.

Results

A total of 64 participants were enrolled. All of the participants successfully inserted both devices on their first attempt in trial 4. Fastrach was applied 1 s faster in trial 4 than the iLTS-D (median ‘time to ventilation’ Fastrach: 13.5 s., iLTS-D: 14.5 s., p = 0.04). All participants successfully intubated through both devices in trial 4. There was no difference in ‘time to tracheal ventilation’ by tracheal intubation between either device (median ‘time to tracheal ventilation’: Fastrach: 14.0 s., iLTS-D: 14.0 s., p = 0.16).

Conclusion

The iLTS-D performed similarly to the ILMA in insertion and intubation times in a manikin setting.

Comparison of Propofol and Ketamine-Propofol Mixture (Ketofol) on Laryngeal Tube-Suction II Conditions and Hemodynamics: A Randomized, Prospective, Double-Blind Trial

OBJECTIVE

The aim of our study is to compare the effect of ketamine-propofol mixture (ketofol) and propofol on the laryngeal tube-Suction II (LTS II) insertion conditions and hemodynamics.

METHODS

Eighty American Society of Anesthesiologists class 1 and 2 patients were divided into 2 random groups to receive either 1 µg/kg remifentanil and propofol 2 mg/kg in Group P (n = 40), or 1 µg/kg remifentanil and ketofol (using a 1:1 single syringe mixture of 5 mg/mL ketamine and 5 mg/mL propofol) in Group K (n = 40) before induction of anesthesia. After induction, LTS II was inserted. Heart rate and noninvasive blood pressure were recorded before induction of anesthesia (t0); immediately following induction (t1); immediately after LTS II insertion (t2); and 3 minutes (t3), 5 minutes (t4), and 10 (t5) minutes after LTS II insertion. Conditions of insertion of LTS II were assessed and scored 1 to 3 using 6 variables as follows: mouth opening, swallowing, coughing, head and body movements, laryngospasm, and ease of LTS II insertion by the same experienced anesthesiologist who did not know the agents. LTS II insertion summed score was prepared depending upon these variables.

RESULTS

In regard to LTS II insertion summed score, Group K was more favorable than Group P (P < 0.05). Apnea duration was longer in Group P (385.0 seconds [range = 195.0-840.0 seconds]) compared with Group K (325.50 seconds [range = 60.0-840.0 seconds]) but this was not statically significant. The heart rate values were significantly lower at all measurement intervals in both groups compared with the baseline values (P < 0.05). There was no difference in heart rate between Group P and Group K. The mean arterial pressure values were significantly lower at all measurement intervals in Group P compared with baseline values (P < 0.05). In Group K, the mean arterial pressure values were significantly lower at all measurement intervals compared with the baseline values, except t2 (P < 0.05). There was a significant difference between Group P and Group K in terms of mean arterial pressure at t3 (P < 0.05).

CONCLUSIONS

We found that ketofol provided better insertion summed score for LTS II than propofol, with minimal hemodynamic changes.

Randomized comparison of the i-gel™, the LMA Supreme™, and the Laryngeal Tube Suction-D using clinical and fibreoptic assessments in elective patients

BACKGROUND

The i-gel™, LMA-Supreme (LMA-S) and Laryngeal Tube Suction-D (LTS-D) are single-use supraglottic airway devices with an inbuilt drainage channel. We compared them with regard to their position in situ as well as to clinical performance data during elective surgery.

METHODS

Prospective, randomized, comparative study of three groups of 40 elective surgical patients each. Speed of insertion and success rates, leak pressures (LP) at different cuff pressures, dynamic airway compliance, and signs of postoperative airway morbidity were recorded. Fibreoptic evaluation was used to determine the devices' position in situ.

RESULTS

Leak pressures were similar (i-gel™ 25.9, LMA-S 27.1, LTS-D 24.0 cmH2O; the latter two at 60 cmH2O cuff pressure) as were insertion times (i-gel™ 10, LMA-S 11, LTS-D 14 sec). LP of the LMA-S was higher than that of the LTS-D at lower cuff pressures (p <0.05). Insertion success rates differed significantly: i-gel™ 95%, LMA-S 95%, LTS-D 70% (p <0.05). The fibreoptically assessed position was more frequently suboptimal with the LTS-D but this was not associated with impaired ventilation. Dynamic airway compliance was highest with the i-gel™ and lowest with the LTS-D (p <0.05). Airway morbidity was more pronounced with the LTS-D (p <0.01).

CONCLUSION

All devices were suitable for ventilating the patients' lungs during elective surgery.

TRIAL REGISTRATION

German Clinical Trial Register DRKS00000760.

Disposable laryngeal tube suction: standard insertion technique versus two modified insertion techniques for patients with a simulated difficult airway

OBJECTIVE

The disposable laryngeal tube suction (LTS-D) is a supraglottic airway device that can be used as an alternative to tracheal tube to provide ventilation. We tested the hypothesis that, with a frontal jaw thrust insertion technique (FIT/JT), the rate of correct placement attempts in patients with a simulated difficult airway by means of a rigid cervical immobilization collar could be significantly increased compared to the standard insertion technique (SIT) recommended by the manufacturer.

METHODS

70 adult patients undergoing trauma surgery under general anaesthesia had an LTS-D inserted, randomly assigned to the SIT or FIT/JT. In the FIT/JT, the operator was standing in front of the patient's head, and forced chin lift to create sufficient retropharyngeal space was performed. The rate of successful tube placements within 180s and with a maximum of two attempts was the main outcome variable. To distinguish between the effects of the frontal approach and the jaw thrust manoeuvre, a third group was studied after completion of the SIT and FIT/JT groups. The standard insertion technique, but with a jaw thrust manoeuvre (SIT/JT), was employed in another 35 consecutive patients.

RESULTS

Overall placement success was 49% (SIT, 17/35 patients, P<0.001), 91% (SIT/JT, 32/35 patients) and 100% (FIT/JT). The time required for successful insertion was shortest in the FIT/JT group (23±6s), and significantly longer in the SIT/JT (42±29s, P<0.001) and SIT groups (51±29s, P<0.0001).

CONCLUSION

In anaesthetised patients with a simulated difficult airway created with a rigid cervical collar, the overall LTS-D placement success was significantly higher when a jaw thrust manoeuvre was performed, regardless of the particular technique used to introduce the LTS-D. Therefore, an intense jaw thrust manoeuvre should be performed whenever an LTS-D is being inserted.

Disposable versus reusable laryngeal tube suction for ventilation in patients undergoing laparoscopic cholecystectomy

BACKGROUND AND OBJECTIVE

The laryngeal tube suction II (LTS-II) is a recent version of reusable supraglottic airway devices allowing gastric drainage. In this prospective, randomized study we compared insertion and ventilation of disposable LTS-II (LTS-D) with reusable type (LTS-II) for airway management under conditions with elevated intra abdominal pressure induced by capnoperitoneum.

METHODS

60 ASA I and II patients undergoing elective laparoscopic cholecystectomy were randomized to receive either a LTS-D (n=30) or LTS-II (n=30) for airway management. After induction of general anaesthesia the devices were inserted, their correct placement was verified and airway leak pressure was measured. Ease of insertion, quality of airway seal, fiberoptic view, risk of gastric insufflation, insertion of nasogastric tube and postoperative pharyngeal morbidity were examined.

RESULTS

First time and second time success rates were comparable for both groups (86% vs. 93% and 96% vs. 96% in LTS-D and LTS-II groups, respectively). One patient in each group could not be intubated after three attempts. After gas insufflation, ventilation of one patient in LTS-D and 2 patients in LTS-II groups was faulty and the patients were intubated with endotracheal tube. Time until delivery of first tidal volume for LTS-D and LTS-II was 20.8 +/- 11.6 s, and 18.2 +/- 4.8 seconds respectively (p = 0.27), fixation and manipulation time was 73.3 +/- 18.5 and 65.5 +/- 16.2 seconds, respectively (p = 0.096). Nasogastric tube insertion was successful in all patients. There were no significant differences in postoperative complaints.

CONCLUSIONS

Both devices provide a secure airway under conditions of elevated intra abdominal pressure.

A critique of elective pediatric supraglottic airway devices

In 1988, when the Laryngeal Mask Airway-Classic (Intavent Orthofix, Maidenhead, UK), was introduced there were only two choices of airway management: tracheal tube or facemask. The supraglottic airway, as we now understand the term, did not exist. Yet, 20 years later, we are faced with an ever increasing choice of supraglottic airway devices (SAD). For many SADs, with the exception of the LMA-Classic and LMA-Proseal (Intavent Orthofix, Maidenhead, UK), there is a lack of high quality data of efficacy. The best evidence requires a randomized controlled trial comparing a new device against an established alternative, properly powered to detect clinically relevant differences in clinically important outcomes. Such studies in children are very rare. Safety data is even harder to establish particularly for rare events such as aspiration. Therefore, most safety data comes from extended use rather than high quality evidence which inevitably biases against newer devices. For reason of these factors, claims of efficacy and particularly safety must be interpreted cautiously. This narrative review aims to present the evidence surrounding the use of currently available pediatric SADs in routine anesthetic practice.

Flexion compromises ventilation with the laryngeal tube suction II in children

BACKGROUND

There are insufficient data as to the influence of the head and neck flexion, extension, and rotation on the ventilation with laryngeal tube suction II (LTS II). The purpose of this study was to investigate the influence of the head and neck position on oropharyngeal sealing pressure (primary outcome) and ventilation score (secondary outcome) during ventilation with the LTS II in children.

METHODS

We studied 33 children scheduled for elective surgery. Oropharyngeal sealing pressure and ventilation score were measured with the head and neck in a neutral position, flexed, extended and rotated to the right. The ventilation score was scored from 0 to 3 based on three items (no leakage with an airway pressure of 15 cmH2O, bilateral chest excursion, and a square wave capnogram; each item scored 0 or 1 point). Peak inspiratory pressure (PIP) at a tidal volume of 10 ml x kg(-1) and fiberoptic laryngeal views were also assessed in each position.

RESULTS

Although the sealing pressure was lower in the extended position [22 (8) cmH2O] than that in the neutral position [25 (7) cmH2O], there was no significant leakage during ventilation with a tidal volume of 10 ml x kg(-1). In the neutral, extended and rotated positions, the median ventilation scores were better (3 point respectively) than that with the head and neck flexed (1 point). PIP was decreased with the head and neck extended or rotated but was significantly increased in flexion position. During fibreoptic examination, the vocal cords were more easily seen in extension and right rotation, compared with the neutral position and flexion.

CONCLUSIONS

Although oropharyngeal sealing pressure is decreased with the head and neck extended, effective ventilation with LTS II can be performed like in the neutral position or the rotated position. While the sealing pressure is maintained with the head and neck flexed, flexion compromises the ventilation with LTS II in children.