The Use of the Laryngeal Mask Airway During Guidewire Dilating Forceps Tracheostomy

Laryngeal mask airway versus endotracheal tube for percutaneous dilatational tracheostomy in critically ill adults

BACKGROUND

Percutaneous dilatational tracheostomy (PDT) is one of the most common bedside surgical procedures performed in critically ill adults, on intensive care units (ICUs), who require long-term ventilation. PDT is associated with relevant life-threatening complications: Cuff rupture or accidental extubation may lead to hypoxia, aspiration or loss of airway. Puncture of the oesophagus, or creating a false passage during dilatation or replacement of the tracheostomy tube, can lead to pneumothorax or emphysema. Wound infections may occur which can cause mediastinits, especially after creation of false passage or in early tracheotomized post-sternotomy patients after cardiac surgery. During the procedure, the patient's airway can be secured with an endotracheal tube (ETT) or a laryngeal mask airway (LMA). This is an updated version of the review first published in 2014.

OBJECTIVES

To assess the safety and effectiveness of LMA versus ETT in critically ill adults undergoing PDT on the ICU.

SEARCH METHODS

We searched the following databases to 9 January 2018: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase. We searched for reports of ongoing trials in the metaRegister of Controlled Trials (mRCT). We handsearched for relevant studies in conference proceedings of five relevant annual congresses. We contacted study authors and experts concerning unpublished data and ongoing trials. We searched for further relevant studies in the reference lists of all included trials and of relevant systematic reviews.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared use of laryngeal mask airways versus endotracheal tubes in critically ill adults undergoing elective PDT in the ICU, without injuries to or diseases of the face or neck. We imposed no restrictions with regard to language, timing or technique of PDT performed.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and methodological quality of each study and carried out data extraction. Our primary outcomes were all-cause mortality, procedure-related mortality and tally of participants with one or more serious adverse events. Where possible, we combined homogeneous studies for meta-analysis. We used Cochrane's 'Risk of bias' tool and used GRADE to assess the quality of evidence for key outcomes.

MAIN RESULTS

We included nine RCTs in this review involving 517 participants.Studies had a high or unclear risk of bias. The main reason for this was low methodological quality or missing data, even after study authors were contacted. Study size was generally small, with a minimum of 40, and a maximum of 73 participants.In one study (40 participants), three deaths in the LMA group and two deaths in the ETT group were reported, although none of the deaths were related to the procedure (very low-quality evidence).Five studies (281 participants) reported on procedure-related deaths, stating that no procedure-related death occurred at all (very low-quality evidence).It is uncertain whether there is a difference in the number of people experiencing one or more serious adverse event(s) between LMA and ETT (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.41 to 1.80; 467 participants, 8 studies, very low-quality evidence).The duration of the procedure may be shorter in the LMA group (mean difference (MD) -1.46 minutes, 95% CI -1.92 to -1.01 minutes; 6 studies, 324 participants, low-quality evidence).However failure of procedure, as allocated by randomization, requiring conversion to any other procedure, may be higher in the LMA group (RR 2.82, 95% CI 1.22 to 6.52; 8 studies, 439 participants, low-quality evidence).We did not find any clear evidence of a difference between ETT and LMA groups for all other outcomes. Only one study provided follow-up data for late complications related to the intervention, showing no clear evidence of benefit for any treatment group.

AUTHORS' CONCLUSIONS

Evidence on the safety of LMA for PDT is too limited to allow conclusions to be drawn on either its efficacy or safety compared with ETT. Although the LMA procedure may shorten the period during which the airway is insecure, it may also lead to higher conversion rates. Also, late complications have not been investigated sufficiently. These results are primarily based on single-centre trials with small sample sizes, and therefore the level of evidence remains low. Studies with low risk of bias focusing on late complications and relevant patient-related outcomes are necessary for definitive conclusions on safety issues related to this procedure. The dependency of the successful placement of a LMA on the type of LMA used should also be further assessed.There are two studies awaiting classification that may alter the conclusions once assessed.

Laryngeal mask airway versus endotracheal tube for percutaneous dilatational tracheostomy in critically ill adult patients

BACKGROUND

Percutaneous dilatational tracheostomy (PDT) is one of the most common bedside surgical procedures performed in critically ill adult patients on intensive care units (ICUs) who require long-term ventilation. PDT is generally associated with relevant life-threatening complications (e.g. cuff rupture leading to possible hypoxia or aspiration, puncture of the oesophagus, accidental extubation, mediastinitis, pneumothorax, emphysema). The patient's airway can be secured with an endotracheal tube (ETT) or a laryngeal mask airway (LMA).

OBJECTIVES

To assess the safety and effectiveness of ETT versus LMA in critically ill adult patients undergoing PDT on the ICU.This review addresses the following research questions.1. Is an LMA more effective than an ETT in terms of procedure-related or all-cause mortality?2. Is an LMA safer than an ETT in terms of procedure-related life-threatening complications during a PDT procedure?3. Does use of an LMA influence the conditions for performing a tracheostomy (e.g. duration of procedure)?

SEARCH METHODS

We searched the Cochrane Database of Systematic Reviews (CDSR); the Cochrane Central Register of Controlled Trials (CENTRAL) 2013, Issue 6 (part ofThe Cochrane Library); MEDLINE (from 1984 to 27 June 2013) and EMBASE (from 1984 to 27 June 2013). We searched for reports of ongoing trials in the metaRegister of Controlled Trials (mRCT). We handsearched for relevant studies in conference proceedings of the International Symposium on Intensive Care and Emergency Medicine (ISICEM), the Annual Congress of the European Society of Intensive Care Medicine (ESICM), the Annual Congress of the Society of Critical Care Medicine (SCCM), the American Thoracic Society (ATS) and the Annual Meeting of the American College of Chest Physicians (ACCP). We contacted study authors and experts concerning unpublished data and ongoing trials. We searched for further relevant studies in the reference lists of all included trials and of relevant systematic reviews identified in theCDSR.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared use of endotracheal tubes versus laryngeal mask airways in critically ill adult patients undergoing PDT on the ICU. We imposed no restrictions with regard to language, timing or technique of PDT performed.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility and methodological quality of each study and carried out data extraction. We resolved disagreements by discussion. Our primary outcomes were all-cause mortality, procedure-related mortality and tally of participants with one or more serious adverse events. When available, we reported on our secondary outcomes, which included duration of the procedure, failure of the procedure requiring conversion to any other procedure, time to extubation after tracheostomy, length of ICU stay after tracheostomy, length of hospital stay after tracheostomy and any other serious adverse events. When possible, we combined homogeneous studies for meta-analysis. We used the risk of bias tool of The Cochrane Collaboration to assess the internal validity of all included studies in six different domains.

MAIN RESULTS

We included in this review eight RCTs involving 467 participants. The included trials exclusively assessed critically ill participants (e.g. with head injury, neurological disease, multi-trauma, sepsis, acute respiratory failure (ARF) and/or chronic obstructive pulmonary disease (COPD)). Internal validity was considerably low in studies with a high or unclear risk of bias. The main reason for this was low methodological quality or missing data, even after study authors were contacted. Study size was generally small, with a minimum of 40 and a maximum of 73 participants. Only one study (40 participants) reported on overall mortality, showing no clear evidence of a difference between treatment groups (risk ratio (RR) 1.5, 95% confidence interval (CI) 0.28 to 8.04, Fisher test P value 1.0, low-quality evidence). Four studies (231 participants) reported that no procedure-related deaths occurred with any intervention. Seven studies reported the numbers of participants with adverse events, showing no clear evidence of benefit of either LMA or ETT during PDT (RR 0.73, 95% CI 0.35 to 1.52, P value 0.41, low-quality evidence). The tally of participants in included studies with adverse events ranged from 0% to 33% in the LMA group and from 0% to 50% in the ETT group. However, the duration of the procedure was significantly shorter in the LMA group (mean difference (MD) -1.46 minutes, 95% CI -1.92 to -1.01 minutes, 324 participants, P value ≤ 0.00001, low-quality evidence). No clear evidence of a difference between ETT and LMA groups was found for all other outcomes. Only one study provided follow-up data for late complications related to the intervention, showing no clear evidence of benefit for any treatment group.

AUTHORS' CONCLUSIONS

Evidence on the safety of LMA for PDT is too limited to allow conclusions to be drawn on its efficacy or safety compared with ETT. Although the LMA procedure is shorter because of optimal visual conditions, its effect on especially late complications has not been investigated sufficiently. Studies focusing on late complications and relevant patient-related outcomes are necessary for definitive conclusions on safety issues related to this procedure.

A prospective randomised controlled trial of the LMA Supreme vs cuffed tracheal tube as the airway device during percutaneous tracheostomy

We studied the performance of the LMA Supreme against a cuffed tracheal tube, our standard method of airway control during percutaneous tracheostomy, in 50 consecutive patients from three general critical care units. The primary outcome measure was adequacy of ventilation calculated as the difference in arterial carbon dioxide tension before and after tracheostomy. On an intention-to-treat analysis, there was no difference in the increase in arterial carbon dioxide tension between groups, with a median (IQR [range]) for the LMA Supreme of 0.9 (0.3-1.6 [0-2.8]) kPa, and for the tracheal tube of 0.8 (0.4-1.2 [0-2.5]) kPa, p = 0.82. Eight patients out of 25 (32%) crossed over from the LMA Supreme group to the tracheal tube group before commencement of tracheostomy due to airway or ventilation problems, compared with none out of 25 in the tracheal tube group, p = 0.01, and tracheostomy was postponed in two patients in the LMA Supreme group due to poor oxygenation. There were more clinically important complications in the LMA Supreme group compared with the tracheal tube group.

Percutaneous dilational tracheostomy

Tracheostomy is a commonly performed intervention with several benefits in the treatment of patients with chronic respiratory failure. Percutaneous dilational tracheostomy techniques have allowed bedside tracheostomy placement in the modern intensive care unit. Percutaneous dilational tracheostomy can be safely performed by interventional pulmonologists, medical intensive care physicians, and surgical specialists. When performed with the assistance of adjuncts, such as flexible bronchoscopy, the percutaneous dilational method has a favorable complication rate, efficiency, and cost profile compared with surgical tracheostomy.

Laryngeal mask airway for airway control during percutaneous dilatational tracheostomy

Percutaneous dilatational tracheostomy is a common bedside procedure in critical care for patients requiring prolonged mechanical ventilation. The traditional technique requires withdrawal of the endotracheal tube to a proximal position to facilitate tracheostomy insertion, but this carries the risk of inadvertent extubation and does not prevent cuff rupture. Use of a supraglottic airway such as the laryngeal mask airway may avoid these risks and could provide a safe alternative to the endotracheal tube. We present an appraisal of the literature to date. We found reasonable evidence to show improved ventilation and bronchoscopic visualisation with the laryngeal mask airway, but this has not been translated into improved outcome. There is currently insufficient evidence to draw conclusions about the safety of the laryngeal mask airway during percutaneous dilatational tracheostomy.

[Extraglottic airway devices in the intensive care unit]

Extraglottic airway devices (EGA) are not only used in routine anaesthesia practice, they also have a distinct value for in-hospital and out-of-hospital difficult airway management. In the environment of the intensive care unit (ICU) EGA are not used on a regular basis. However, expertise and knowledge regarding EGA coming from the operating theatre or the out-of-hospital setting may also be of value for the ICU setting. This review presents the potential indications for EGA on the ICU for the management of difficult airway situations as well as during percutaneous tracheotomy. Furthermore, the possible advantages of EGA during postoperative recovery from anaesthesia as well as termination of controlled ventilation for intensive care patients are discussed.

[Dilatation tracheotomy update : indications, limitations and management of complications]

Percutaneous dilatational tracheotomy is a standard procedure today for transient airway management in intensive care units. When correctly indicated and applied, preferably following interdisciplinary case discussion with the otolaryngologist, PDT seems to be as safe as classical surgical tracheotomy. The latter is the alternative when PDT is contraindicated. There is currently a trend towards one-step PDT procedures. In addition to the permanent necessity for an alternative airway, there is a series of clearly defined contraindications to PDT. In such cases, only surgical tracheotomy is viable. In contrast to surgical tracheotomy, PDT presents more challenges to the physicians and nursing staff in order to avoid specific complications such as re-cannulation into a via falsa followed by acute dyspnea. The otolaryngologist is an important partner in the management of PDT-related complications due to his discipline-specific experience. Further prospective trials, especially concerning long-term complications, are needed to answer the question of whether PDT or surgical tracheotomy is the best method in situations with overlapping indications.