Goneppanavar Umesh

Tongue Traction is as Effective as Jaw Lift Maneuver for Trachlight-guided Orotracheal Intubation

OBJECTIVE The jaw lift maneuver has been traditionally used to facilitate Trachlight-guided orotracheal intubation. The aim of this study was to compare the jaw lift maneuver with another potentially useful maneuver, tongue traction, for facilitating Trachlight-guided orotracheal intubation. METHODS This study was prospective and randomized in design. A single experienced investigator performed Trachlight-guided orotracheal intubations in 100 adult patients with clinically normal airways undergoing elective surgeries under general anesthesia with paralysis. Patients were divided into two groups: Group J (jaw lift); and Group T (tongue traction using a padded artery forceps). Three parameters were recorded: search time (device insertion to midline glow); time to intubate (device insertion to glow at suprasternal notch); and time to confirm (device insertion to confirmation of placement by capnography). RESULTS All patients were intubated successfully using the Trachlight. Only one patient in Group J required more than two attempts for successful intubation. First and second attempt success rates were, respectively, 86% and 98% in Group J, and 92% and 100% in Group T. Mean search time, time to intubate and time to confirm were comparable: 6.36 ± 4.20 seconds, 11.23 ± 6.69 seconds and 21.59 ± 7.69 seconds, respectively, in Group J, and 6.81 ± 4.53 seconds, 10.79 ± 6.02 seconds and 22.80 ± 7.85 seconds, respectively, in Group T. CONCLUSION The tongue traction maneuver is as good as the jaw lift maneuver with regard to the success rate and time taken for Trachlight-guided orotracheal intubation.

Low minimum alveolar concentration alarm: a standard for prevention of awareness during general anaesthesia maintained by inhalational anaesthetics.

Awareness during general anaesthesia is a rare but significant problem that can be frightening to the patients. We suggest that newer generation monitors should include this facility to provide a low alarm limit to MAC settings so as to improve the quality of patient care. Also we suggest that a “near empty” alarm be incorporated into vaporizers which can warn the anaesthesiologist prior to development of possible light plane of anaesthesia. We hope that adopting these two features can help enhance patient safety and can further aid in quality assurance.

Carina as a useful and reliable radiological landmark for detection of accidental arterial placement of central venous catheters

Central venous catheters are commonly used in the management of critically ill patients. Their insertion can be challenging in hemodynamically unstable patients and in those with altered thoracic anatomy. Although ultrasound guided insertion can reduce this problem, this facility may not be available in all locations and in all institutions. Accidental arterial puncture is one of the very serious complications that can occur during central venous catheter insertion. This is usually detected clinically by bright color and projectile/pulsatile flow of the returning blood. However, such means are known to be misleading especially in hypoxic and hemodynamically unstable patients. Other recognized measures used to identify arterial puncture would be blood gas analysis of the returning blood, use of pressure transducer to identify waveform pattern and the pressures. In this article, we propose that trachea and carina can be used as a reliable radiological landmark to identify accidental arterial placement of central venous catheters. We further conclude that this information could be useful especially when dealing with post-resuscitation victims and hemodynamically unstable critically ill patients.

Solutions to kinking of the side stream carbon dioxide sampling line

A sidestream gas analyzer samples gases from a sampling port in an adapter placed in a breathing circuit. Kinking of the sampling line of the sidestream capnogram is not an uncommon problem during head and neck surgeries. We have identified the main problem for kinking of the sampling line in head and neck surgeries to be its vertical origin from the connecting point of the breathing circuit. Angled attachment of the sampling line at its connection to the breathing circuit can minimize this problem of kinking significantly as has been shown by our study.

Leak in the breathing circuit: CO2 absorber and human error

A couple of reports in literature have mentioned CO2 absorbers to be the cause for breathing circuit leak during anesthesia. Defective canister, failure to close the absorber chamber and overfilling of the chamber with sodalime were the problems in these reports. Among these, the last two are reports of human error resulting in problems. We report a case where despite taking precautions in this regard, we experienced a significant leak in the system due to a problem with the CO2 absorber, secondary to human error.

Immediate postoperative airway obstruction secondary to airway edema following tumor excision from the neck

A 46-year-old woman was scheduled for excision of a malignant peripheral nerve sheath tumor from the neck. The tumor had caused deviation of the trachea to the left and partial obstruction of the superior vena cava. Her upper airway at laryngoscopy after induction of anesthesia was normal. During tumor resection there were transient phases characterized by the complete disappearance of the peripheral oxygen saturation (SpO2) and radial artery tracings. At the end of the operation, the trachea was extubated after ensuring adequate antagonization of neuromuscular blockade. However, immediately post-extubation, she showed signs of acute airway obstruction that necessitated reintubation of the trachea. Laryngoscopy revealed significant edema of the upper airway and vocal cords, requiring a smaller size tracheal tube. Many reports suggest the development of significant airway edema 24 h after such surgery. Our report highlights the fact that this can happen in the immediate postoperative period also. Some authors suggest that, in such surgery, extubation should routinely be done over pediatric tube exchangers. Routine leak testing and direct laryngoscopic/fiberoptic evaluation of the upper airway prior to extubation may also help. While our report reaffirms these points, it also stresses the importance of intraoperative monitoring for the compression of the great vessels, which may serve as a useful indicator of the early development of airway edema.

Suxamethonium stands the test of time: it is too early to say goodbye

We read Lee’s article with great interest [1], in which the author suggests that in present day practice suxamethonium finds its utility in only a handful of situations. Under the subheading ‘a new challenge to suxamethonium’, the author further explains that with the availability of rocuronium and sugammadex, even in these situations there is no real role left for suxamethonium and concludes that suxamethonium has done its job! However the author has failed to mention the utility of suxamethonium in certain situations where it still plays a vital role. One of these is the management of laryngospasm where suxamethonium is still considered the gold standard [2, 3]. Intravenous suxamethonium 0.1–3 mg.kg together with atropine 0.02 mg.kg has been widely used for the management of laryngospasm [3]. Although intravenous propofol can be used in the management of laryngospasm, suxamethonium is the only effective drug that is available to treat laryngospasm in the absence of an intravenous access, as it can be administered by the sublingual, intramuscular or the intraosseous route [2]. No studies to date mention the utility of rocuronium and sugammadex in the management of laryngospasm. Suxamethonium may also have a role to play where the neuromuscular blockade of vecuronium or rocuronium has been effectively antagonised with sugammadex towards the end of the surgical procedure but the situation demands continuation of paralysis for a little longer period. As has been described in another article in the same issue, either a benzylisoquinolinium nondepolarising relaxant or suxamethonium can be used in this situation [4]. Here suxamethonium may score over the benzylisoquinolinium compounds as they take approximately 3 min to establish reliable neuromuscular blockade and have an intermediate duration of action which is undesirable in most situations. In contrast, since the neuromuscular blockade would have been antagonised by sugammadex, suxamethonium is an attractive option to provide immediate but brief reliable paralysis as its effect is unlikely to get prolonged unlike when it is administered after reversal of neuromuscular blockade with anticholinesterases. Sugammadex has been found to antagonise the effects of aminosteroids within minutes [4] which may encourage the clinicians to use higher doses of aminosteroids to ensure profound relaxation until the end of the procedure. One must be cautious as such actions may result in a greater risk of awareness as total absence of movement may mask inadequate anaesthesia or analgesia [5, 6]. One important adverse effect of suxamethonium that has not been mentioned in the article is its ability to undergo autodegradation over a period during its storage and its photosensitivity which may contribute to bradyarrhythimas [7]. We conclude that with the availability of sugammadex it is obvious that the sun of suxamethonium is beginning to set while aminosteroids will be in the ascendant in most situations. However, suxamethonium has stood the test of time and is here to stay for some more time until effective replacements are found to the above mentioned situations.

A technique to overcome inability to advance a tracheal tube over a fiberscope during nasotracheal intubation

To the Editor: Difficulty in advancing the tracheal tube over a flexible fiberscope (FOB) despite having the FOB in the trachea can be a frustrating experience. It happens because of deviation of the course of the tracheal tube from that of the FOB towards laryngeal structures [1, 2]. Multiple techniques have been reported in the literature to overcome this problem during nasotracheal fiberoptic intubation. Counterclockwise rotation of the tracheal tube is commonly used to overcome this problem. Other suggested ways are use of a tapered tracheal tube without bevel, and use of a Parker Flex-Tip tube [1, 2]. It has been found that the greater the gap between the FOB and the tracheal tube, the higher is the likelihood of facing this problem [1, 2]. Measures used to overcome this problem are to interpose a smaller diameter uncuffed tracheal tube or an Aintree intubating catheter or Cook airway exchange catheter between the tracheal tube and the fiberscope minimize the gap between the tracheal tube and the FOB [1, 2]. It is a well known fact that the tracheal tube usually aligns itself in front of the glottis when passed from the nose to the oropharynx. This forms the basis for the blind nasal intubation technique and for the ‘tube-first approach’ during nasal fiberoptic intubation [3, 4]. Based on a similar principle, we have successfully performed nasal fiberoptic guided intubation in two spontaneously breathing patients when faced with the difficulty in advancing the tracheal tube. In our technique, the fiberscope was withdrawn until its tip was outside the glottis. The tip of the fiberscope was then made to project just outside the tip of the tracheal tube by first advancing the tracheal tube beyond the tip of the fiberscope and later withdrawing it until its tip disappeared from the visual field of the fiberscope. Attempts were then made to align the ‘fiberscope–tracheal tube assembly’ (FTA) in front of the glottis with the lever of the fiberscope in the neutral position. This can be achieved by adjusting the position of the pillow and the neck. When this is achieved, the FTA was advanced into the glottis when the vocal cords were maximally abducted. Unless the tip of the fiberscope is in neutral position at the time of advancing the FTA into the glottis, the procedure is likely to fail as the tip of the tracheal tube would go in a different direction than the tip of the fiberscope. When correctly done, this technique offers the unique advantage of being able to advance the tracheal tube under vision, thus minimizing contact of the FTA with the laryngeal structures and aiding in unhindered passage of the tracheal tube into the glottis. Advancing the tracheal tube over the fiberscope is a blind procedure in routine fiberoptic intubations and our technique helps to overcome this problem. We are confident that our technique adds another powerful technique to existing solutions for overcoming the peculiar problem of difficulty in advancing a tracheal tube over a fiberscope during nasal intubation.

Lightwand for confirming tracheal intubation in the presence of severe postintubation bronchospasm.

SIR—A 19-month-old child (10.8 kg) was scheduled for incision and drainage of multiple neck abscesses. He was having a hyperreactive airway because of active upper and lower respiratory tract infection. His heart rate was 118/min and room air SpO2, 95%. Following intravenous administration of 30 mg of propofol and 15 mg of succinylcholine, he was ventilated with bag and mask with sevoflurane in oxygen till laryngoscopy attempt by the resident anesthesiologist. He could visualize only the epiglottis despite optimal external laryngeal manipulation (OELM) with both MacIntosh and Miller blades. A blind attempt at intubation was made with a styleted uncuffed tracheal tube (4.5 mm ID). Auscultation over the chest and epigastrium failed to confirm intubation while the side stream capnograph did not show waveform. An esophageal detector device (EDD) also failed to confirm the position of the tracheal tube. Suspecting an esophageal intubation, with the tracheal tube still in situ, laryngoscopy was performed by a senior anesthesiologist. After deliberately pushing the tracheal tube toward the hard palate with OELM, the laryngoscopist opined that the tracheal tube was probably in the glottis as a glimpse of the arytenoids was visualized and that the tracheal tube appeared to be going above the arytenoids. At this stage, a pediatric size lightwand (Trachlight ; Laerdal Medical Corporation, Armonk, NY, USA) was introduced into the tracheal tube that elicited a well-circumscribed midline glow in the anterior neck confirming tracheal intubation. The child remained stable hemodynamically although the SpO2 dropped to 85% by this time (approximately 90 s). Subsequently, positive pressure ventilation was continued with sevoflurane in oxygen and the capnogram appeared several seconds following resumption of ventilation and had an upsloping pattern indicating bronchospasm. By this time, the air entry had improved and rhonchi were audible on auscultation and treated with salbutamol and propofol. A suction catheter could easily be passed through the tracheal tube, and minimal thin secretions were suctioned. Further management of the child was uneventful. Post extubation, examination of the tracheal tube did not show any blockade of its lumen. At extubation, the child had mild bronchospasm, which was treated again with salbutamol nebulization. Capnography is the gold standard for rapid and reliable identification of tracheal intubation. However, there are instances where capnography has failed to detect tracheal intubation such as block in the trachea or tracheal tube or the sampling port for capnogram, large leak around the tracheal tube and cardiac arrest (1). In such cases, it has been suggested to perform a repeat laryngoscopy with the tube in situ and if necessary to push the tube toward the hard palate for better visualization of the laryngeal structures. If this fails to confirm passage of the tube between the vocal cords, an EDD and five-point auscultation (four quadrants of the chest and the epigastrium) may be useful (1,2). However, all these measures failed to confirm tracheal intubation in our case. This is because, capnography, EDD and ausculatory methods require adequate gas flow across the tracheobronchial tree to be effective in identifying tracheal intubation. During intense bronchospasm (silent chest on auscultation), these are likely to fail as hardly any gas flow occurs across the tracheobronchial tree. An anterior glottis contributed to failure to visualize the glottis during laryngoscopy. Absence of any sounds on auscultation over the epigastrium and a suspected presence of the tracheal tube above the arytenoids were the only hints for persisting with the tracheal tube. As lightwand relies on transillumination of light and not on the gas flow across the tracheobronchial tree for detection of tracheal intubation, it helped confirm tracheal intubation in our case. This not only prevented further intubation attempts but also averted possible worsening of the scenario. Mechanical obstruction of the tube was ruled out as we could easily pass the lightwand initially and the suction catheter later through the tracheal tube. A transport delay in the side stream capnograph (normally ranges between 1 and 5 s) as a cause for false negative result was ruled out by the absence of capnogram despite positive pressure ventilation for more than 30 s (3). Although passing a suitable fibrescope through the tracheal tube could have confirmed the diagnosis, it was not considered as a feasible option as this was not available at hand and transporting it to our theater could have taken several minutes. Therefore, based on our experience we conclude that intense bronchospasm (silent chest) following tracheal Correspondence

Arterial line for monitoring SpO2 in patients with ischemic peripheries

Monitoring the oxygenation status of patients with poor peripheral perfusion or ischemic peripheries is challenging in view of unreliable or unrecordable pulse oximeter data. In this article we describe a very simple and innovative technique of using the arterial line for reliable recording of arterial oxygen saturation (SpO2) in such patients. We conclude that the arterial line can be used as an extension of the artery and SpO2 may be reliably measured using the arterial line in such patients as long as the blood in the arterial tubing is pulsatile and a good contact is ensured between the arterial tubing and the sensor of the pulse oximeter.