[Comparison of the Supreme Laryngeal Mask Airway(SLMA), single use, with the reusable Proseal Laryngeal Mask Airway(PLMA) in anesthetized adult Japanese patients]

BACKGROUND

Supreme laryngeal mask airway (SLMA) is a single use, new supraglottic airway device with anatomically designed curved airway conduit. It has second channel for gastric tube insertion. We compared the performance of the SLMA with that of the Proseal LMA (PLMA), the older reusable LMA, during anaesthesia in spontaneously breathing adult patients.

METHODS

One hundred adult patients were studied in a prospective randomized controlled study. Insertion time, first attempt success rates, leak pressure, ease of gastric tube placement, and the incidence of blood staining on removal, as well as sore throat and hoarseness were compared. For statistical analyses, Student's t test, Mann-Whitney's U test, and Fisher's exact test were used where appropriate, and P<0.01 considered significant.

RESULTS

SLMA provided faster insertion time (11 vs 18 seconds, P<0.01). Leak pressure was higher for PLMA (25 vs 28cmH2O, P<0.01). First attempt success rates, gastric tube placement and the incidence of complications were similar.

CONCLUSIONS

Our result indicated that SLMA can be inserted faster without inserting one's finger into patient oral cavity. Leak pressure was lower but acceptable for clinical use in spontaneously breathing anesthetized adult patients.

Adding a conduit to GlideScope blade facilitates tracheal intubation. Prospective randomized study

OBJECTIVE

To determine the effect of modifying the GlideScope (GVL) blade on the intubation time.

METHODS

This prospective study was conducted at the Department of Anesthesia, King Abdulaziz University Hospital, Jeddah, Saudi Arabia between June 2011 and October 2011. Sixty patients requiring endotracheal tube (ETT) intubation for elective surgery in whom airway was anticipated normal were randomly allocated to one of 2 groups. Group M (n=30): intubated via a modified GVL blade in which a tube conduit along the side of the GVL blade was created to allow the passage of ETT through the cords. Group C (n=30): intubated with the conventional GVL blade and rigid intubating stylet.

RESULTS

Time to successful tracheal intubation (TTI) was 39.6+/-2.1 seconds in Group M versus 66.4+/-8.3 seconds in Group C (p=0.0001), tracheal intubation was deemed more easily in Group M than in Group C (VAS 2+/-1 versus 6+/-1, p=0.0001), and all patients in Group M were successfully intubated on the first attempt when compared with 90% in Group C (p=0.009).

CONCLUSION

The addition of a conduit to the GVL blade made the passage of the ETT easier and TTI shorter without increasing adverse events or intubation failure.

Airway management using the ProSeal laryngeal mask airway in a child with Goldenhar syndrome

Children with congenital anomalies such as Goldenhar syndrome affecting the airway can be a problem for the anaesthesiologist. We present the case of an 18 month-old child with Goldenhar syndrome, in whom the ProSeal Laryngeal Mask Airway was successfully used for inguinal hernia surgery.

[Total intravenous and combined general anaesthesia]

In this review TIVA and combined general anaesthesia are not opposed to each other, but considered as having common physiological, clinical, pharmacological, technological and methodological features. This approach will help to borrow useful qualities of each anaesthesia method.

[The i-gel: its efficacy in 120 patients undergoing general anesthesia]

BACKGROUND

The i-gel, which has been introduced into clinical practice in Japan in 2010, has a potential role in maintaining a clear airway during general anesthesia.

METHODS

We retrospectively studied the efficacy of the i-gel in 120 patients who had undergone elective surgery under general anesthesia.

RESULTS

It was always possible to insert the i-gel at the first attempt. However, there was gasleak around the device in 5 patients, and the device was reinserted. It was possible to obtain adequate ventilation via the i-gel in 117 patients (97.5%) within two attempts at insertion. Insertion was judged easy in 106 patients, somewhat difficult in 12 patients, and difficult in 2 patients. The mean minimum airway pressure at which gas leaked around the device was 26.4 cmH2O, with no gasleak at the airway pressure of 30 cmH2O in 66 of 120 patients. In no patients, did any airway complications, such as airway obstruction, occur during positive pressure ventilation, during the return of spontaneous breathing around the end of surgery, and during emergence from anesthesia. After removal of the i-gel, there was no stain of blood on the device.

CONCLUSIONS

We believe that the i-gel is useful in maintaining a clear airway during general anesthesia.

[Parameters of controlled mechanical lung ventilation and external respiratory function during thoracoscopic surgeries in children of different age groups]

The purpose of the study is to estimate the parameters of mechanical ventilation and respiratory function during videotorachoscopic surgeries in children. 73 anesthesias were conducted in children aged 5 to 16 years of age. During the study, a detailed monitoring of respiratory function and parameters of mechanical ventilation was carried out. Indicators reflecting the lung function remained stable in all phases of the study. Parameters of mechanical ventilation during the study varied. Changes in PIP and MAP were similar in all age groups. The maximum changes of compliance were in the third group. One-lung ventilation is safe under certain conditions: increasing FiO2 from 0.5 to 1, the reduction of tidal volume up to 5-5.3 ml/kg, the use of a size or a half size smaller cuffed endotracheal tubes for intubation of the right and left main bronchus compared to those for tracheal intubation. For the intubation of the right main bronchus the endotracheal tube with the Murphy eye should be used, for the means ventilation of the upper lobe of the right lung. If the minute volume of breathing is adequate and there is no preoperative hypercapnia, the elimination of CO2 for one-lung ventilation is not disrupted and the tension of CO2 in arterial blood increases.

[The feasibility of Supreme laryngeal mask airway in gynecological laparoscopy surgery]

OBJECTIVE

To explore the safety, efficacy and side effect of Supreme laryngeal mask airway (LMA) used in gynecological laparoscopy.

METHODS

From Oct. 2009 to Apr. 2010 in First Hospital of Peking University, 125 patients undergoing general anesthesia for elective gynecological laparoscopy were reviewed, 69 of which were dealt with Supreme LMA (S) and 56 with endotracheal tube (T). After anesthesia induction, changes of HR and MAP were observed during intubation and extubation. The peak inspiratory airway pressure (P(peak)) and P(ET)CO(2) were monitored. Relevant perioperative side effects were recorded.

RESULTS

HR and MAP in group T were increased right after intubation and during extubation (P < 0.05), which were significantly decreased in group S (P < 0.01). P(peak) and P(ET)CO(2) were comparable in the two groups at all the time points (P > 0.05). There was no body movement or coughing at the time of intubation. Group S had less incidence of body movement, coughing and sore throat than group T during extubation (P < 0.05).

CONCLUSION

Supreme LMA can provide the same safe and effective ventilation as intubation and less stress response and side effects in gynecological laparoscopy.

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 (N(2)O) and Sevoflurane (SEV) was measured at the anaesthetists' breathing zone and the patients' mouth using a photoacoustic infrared spectrometer.

RESULTS

N(2)O 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 cmH(2)O, P=0.01). The average leak pressure of the CobraPLA was 24+/-4 cmH(2)O, compared with 20+/-4 cmH(2)O of the LMA classic (P<0.001; all values means+/-SD).

CONCLUSION

Despite higher airway seal pressures, the CobraPLA caused higher intraoperative N(2)O trace concentrations in the anaesthetists' breathing zone.

[Use of the airway scope for rapid sequence induction in the emergency operation]

Rapid sequence intubation is a common procedure in emergency patients at risk for pulmonary gastric aspiration. However, in some of these cases may accompany a difficult airway. The Airway Scope (AWS) has been shown to be useful for difficult airway. We used AWS for rapid sequence intubation in 19 such patients. All patients were successfully intubated without any complication. We believe that AWS is a useful device for rapid sequence intubation.

Type I gore-tex laryngoplasty for glottic incompetence in mobile vocal folds

OBJECTIVE

To determine the effectiveness of gore-tex medialization thyroplasty for the management of glottic incompetence (GI) in patients with mobile vocal folds.

METHODS

Twenty patients with glottic incompetence (GI) and mobile vocal folds were retrospectively analyzed after gore-tex medialization laryngoplasty. Pre- and postoperative outcome measures including grade, roughness, breathiness, asthenia, strain of the voice (GRBAS), glottal function index (GFI), and voice-related quality of life (VRQOL) were compared to detect surgical effectiveness. Two anesthetic subgroups were identified and compared: general anesthesia, via laryngeal mask airway (LMA) anesthetic, and local anesthesia.

RESULTS

Statistically significant differences were identified between pre- and postoperative VRQOL (P<0.0001), GFI (P<0.01), and composite GRBAS (P<0.0001) after a mean follow-up time of 7.8 months. Both the LMA and the local anesthetic subgroups demonstrated similar significance across these measures. GFI and VRQOL scores demonstrate a moderate correlation (ρ=0.71). Perceptual voice quality (GRBAS) correlates slightly better with VRQOL scores (ρ=-0.6; P<0.01) than qualitative measures of glottal function (GFI) (ρ=0.43).

CONCLUSION

Gore-tex thyroplasty provides reliable medium-term improvement in both perceptual and subjective voice parameters in the setting of GI with mobile vocal folds.

[Independent lung ventilation during general anaesthesia--preliminary report]

BACKGROUND

Unitaleral lung pathology presents a serious challenge for the anaesthesiologist. Conventional ventilation usually leads to over distension of the non-affected lung and hypoventilation of the affected lung. The optimal ventilatory strategy in such situations, is intubation with a double lumen tube and independent lung ventilation with two respirators. This is expensive and difficult, especially in an operating room. A novel approach to this problem is based on the use of a single ventilator with a volume splitter, which enables the independent ventilation of each lung, with the same frequency but different volumes, I:E ratios and PEEPs.

METHODS

We used the splitter in thirty-four patients, of both sexes, aged 19-78 years, and scheduled for elective thoracic surgery. All patients were intubated with a double lumen tube and ventilated in the supine and lateral positions with and without the splitter. When the lateral position was used, the volume delivered by the ventilator was split equally to each lung.

RESULTS

In the lateral position, without the splitter, the distribution of gas delivered by the ventilator was unequal: the dependent lung receiving 47.4 +/- 6.8% of the total volume, and the non-dependent lung receiving 52.6 +/- 6.8%. When the splitter was used, both lungs were ventilated with equal volumes. All patients were cardiovasculary stable.

CONCLUSION

A novel method of ventilation during anaesthesia is described, opening up new possibilities for thoracic anaesthesia that allows easy and atraumatic independent lung ventilation.

[BONFILS retromolar intubation fiberscope VS styletscope for oro-tracheal intubation]

BACKGROUND

Battery-powered BONFILS Retromolar Intubation Fiberscope (B-scope) is a nonflexible fiberscope having the same curvature as the Macintosh laryngoscope. Battery-powered StyletScope (S-scope) has a flexible apex whose direction was controlled by grasping a handle. We assessed the operational performance of the two scopes.

METHODS

Fifty patients were randomly allocated in the two groups :25 patients were in the B group (B-scope) and 25 were S group (S-scope) after obtaining written informed consent. We evaluated Mallampati class classification, size of tracheal tube, and intubation time.

RESULTS

There are no significance differences between the two groups in Mallampati class, demographic date and intubation time (23 +/-15 sec in B-group and 26 +/-14 sec in S-group). Both scopes were good in operational performance.

CONCLUSIONS

BONFILS Retromolar Intubation Fiberscope and StyletScope are both good in the operational performance.

Instrumentation for small-animal capnometry

Monitoring of human vital signs - heart rate, respiratory rate, hemoglobin oxygen saturation and others - has become an indispensable part of the standard of care in a hospital setting. For example, vital sign monitoring during administration of general anesthesia is essential, given the role that the anesthesiologist plays in assuming physiologic control. In veterinary settings, however, vital sign monitoring under anesthesia is less common, and may consist simply of a visual assessment of respiratory rate. Vital sign monitoring is especially challenging in small animals, given the high metabolic rates and small volumes under consideration. In this paper, we present a unique nose-cone design and associated instrumentation which allows for measurement of respiratory parameters - e.g., anesthesia gas concentration, inspiratory and expiratory O(2), and inspiratory and expiratory CO(2) (capnometry). Such instrumentation facilitates a physiologic assessment of small animals undergoing general anesthesia, an increasingly important consideration as small animals play a greater role in in vivo biomedical studies. In addition, the techniques proposed herein are suitable for measurement on small respiratory volumes associated with neonatal monitoring.

How American dentists helped pioneer oxygenation of general anesthetics worldwide

Dentists Horace Wells and later William Morton introduced the world to general anesthesia with nitrous oxide and ether, respectively. During the latter half of the 1800s, some of their colleagues actually redefined anesthetic gas mixtures as ones including either room air or oxygen as a carrier gas. American dentists pioneered America's first series of bubble-through anesthetic vaporizers as well as early efforts in anesthesia literature and education. By the end of the 19th Century, America's leading dental supplier, S.S. White, was mass-producing an anesthesia apparatus which combined oxygen with nitrous oxide--a template or catalyst for the design of anesthesia machines worldwide.

[Use of the epiglottic airway I-gel during anesthetic maintenance: first clinical impressions]

The paper gives a concise account of the evolution of epiglottic airways and the emergence of the new product of this class--I-gel (Intersurgical, United Kingdom). It outlines the structural features of I-gel and the authors' experience in using the latter to maintain airway patency during anesthetic maintenance in 34 patients. Based on a review of the scanty data available in the literature on this airway and their clinical experience, the authors come to the conclusion that there is a great variety of I-gel inherent positive characteristics that make this airway highly promising for the needs of current anesthetic maintenance and, possibly, resuscitative care. The authors consider it expedient to expand the use of I-gel to specify the evaluation of its efficiency and competitive capacity of the epiglottic airways that have already well shown themselves.

Less tongue engorgement with lateral placement of the Esophageal Tracheal Combitube

BACKGROUND

The conventional technique of insertion and fixation of the Esophageal Tracheal Combitube (ETC) is occasionally associated with engorgement of the tongue. This study sought to evaluate the efficacy of an alternative placement technique in reducing the incidence of this complication.

METHODS

Thirty ASA I and II adult patients posted for elective surgery under general anaesthesia lasting from 30 to 120 min were randomly divided into two groups (n=15, each). In Group A, the ETC was inserted and fixed in the midline. In Group B, the ETC was inserted along the angle of the mouth and was fixed at this lateral position. Intra-operative occurrence of engorgement of the tongue, the time of such an occurrence and any complaints of post-operative discomfort were recorded.

RESULTS

The overall incidence of engorgement of the tongue in Group A patients (67%) was significantly more (P<0.01) as compared with Group B (17%). The incidence significantly increased (P<0.01) with an increase in the duration of surgery in both the groups. The engorgement persisted into the post-operative period in three patients in Group A and resolved spontaneously in <15 min in each case.

CONCLUSION

Lateral insertion and fixation of the ETC is an easy, safe and effective method of preventing engorgement of the tongue associated with the use of this device without compromising a leak-proof oropharyngeal cavity.

A field-expedient Ohmeda Universal Portable Anesthesia Complete draw-over vaporizer setup

The Ohmeda Universal Portable Anesthesia Complete (U-PAC) draw-over anesthetic system is active in the US Army inventory. It is standard equipment for Certified Registered Nurse Anesthetists assigned to US Army Forward Surgical Teams and Joint Special Operations Command. The purpose of this article is to describe a practical and field-expedient U-PAC draw-over vaporizer setup used during Operation Iraqi Freedom I (February 2003 to July 2003). During the deployment, general anesthesia was administered to 25 patients with penetrating trauma using the Gegel-Mercado setup without system malfunction. This setup strengthens the standard U-PAC draw-over system delivery because it increases fractional inspired oxygen concentrations, promotes hands-free operation, enhances circuit cleanliness reducing cross contamination, and provides an alternate method for draw-over anesthesia administration in austere conditions when a ventilator may not be available or practical. It integrates and builds on the core concepts of draw-over anesthesia delivery in the literature. The Gegel-Mercado setup is combat proven.