In contemporary anaesthesiology, there is increased reliance on more and more sophisticated equipment for airway management. Although this has made the practice of anaesthesia safer, at the same time, there is an increased scope for mishaps to occur due to equipment malfunction and, hence, rigorous pre-anaesthetic equipment check is mandated universally. This holds true as much for equipment that is being used regularly as it is for equipment that is used just once in a while. We present the case of a 30-year-old female with ameloblastoma of mandible, where equipment malfunction led to a foreign body lying precariously close to the larynx. Timely intervention by the anaesthesiologist led to prevention of a catastrophe.
CASE REPORT
A 30-year-old female patient, weighing 50 kg, diagnosed as a case of ameloblastoma afflicting the mandible, was posted for enucleation of tumour under general anaesthesia. Pre-operative routine laboratory investigations were within normal limits, and the patient was accepted for anaesthesia as ASA Gr-I. The airway examination showed Mallampatti Class-II, and a written, informed consent was taken from the patient. In the operation theatre, after standard monitors had been applied and intravenous (iv) access established, the patient was premedicated with ranitidine 50 mg, metoclopramide 10 mg, glycopyrrolate 0.2 mg and butorphanol 1 mg, iv. After pre-oxygenation with 100% oxygen for 3 min, anaesthesia was induced with propofol 100 mg iv and maintained with 1% isoflurane and 66% nitrous oxide, in oxygen. After ensuring adequate bag and mask ventilation (BMV), vecuronium 5.5 mg iv was given for neuromuscular blockade. After 3 min of BMV, intubation was attempted, with the head in sniffing position, using a size #3 MacIntosh laryngoscope blade. As the laryngoscopic view turned out to be Cormack-Lehane Grade-3, BMV was resumed and a McCoy laryngoscope with a size #3 blade was asked for. As we tried to lift the epiglottis by manoeuvring its tip, we found that lever function of the tip was not working. The defective blade was withdrawn immediately. Laryngoscopy was reattempted using a size #4 McCoy blade. On lifting the epiglottis, a metallic foreign object was seen lying near the right pyriform fossa. To prevent its migration inside the larynx, we immediately secured the airway with a 7.0 mm cuffed endotracheal tube. After cuff inflation and fixation of the tube at the angle of the mouth, a repeat laryngoscopy was performed and the foreign body was extracted with the help of Magill forceps. The foreign body was a 7 mm metal rivet, which turned out to be the missing rivet from the fulcrum of the defective blade [Figure 1]. Subsequent check bronchoscopy with a 3.5 mm paediatric fibreoptic bronchoscope ruled out any other foreign body till the secondary bronchii bilaterally. An on-table chest X-ray was also performed, which showed no radio-opaque shadow in the neck, chest or upper abdomen. The surgery, immediate post-operative period and the recovery were uneventful and without any complications. The defective blade, along with the rivet, was returned to the manufacturers for repair.
Figure 1
The detached rivet shown alongside the malfunctioning McCoy laryngoscope blade
The detached rivet shown alongside the malfunctioning McCoy laryngoscope blade
DISCUSSION
McCoy laryngoscope blades with flexible tips are of proven value for improvement of laryngoscopic grade.[1] We could find only one reported case, where the McCoy blade had malfunctioned, but that was in the days when the joint used to be soldered, not riveted.[2] To the best of our knowledge, there is no reported literature of the rivet detaching from the McCoy laryngoscope blade, although a literature search showed several case reports of iatrogenic foreign bodies in and around the trachea.[34] In most of these cases, a common denominator was decreased vigilance on the part of the concerned caregiver. It is common practice to check all routine equipment before administering anaesthesia to a patient but, often, the same vigilance is not exercised for equipment that is required in special scenarios only. When faced with an unanticipated problem, as in our case, the heat of the moment forces us to use the second-line backup devices and equipment without a thorough pre-use check. Needless to say, the complications of malfunction can be catastrophic.On seeing the foreign body lying close to the vocal cords, the investigator curbed the natural instinct of grabbing the foreign body and, instead, secured the airway first. This, in the opinion of all authors, was the correct decision, as the cylindrical metal rivet had every chance of slipping out of the Magill forceps and falling straight down into the trachea. The authors suggest simple solutions for avoiding such accidents. Firstly, regular checks and servicing should be done of all emergency equipment, especially those with movable parts and joints, which are not used routinely, and a record should be maintained and counter-checked. Secondly, specifically pertaining to the problem in question, commercially available disposable laryngoscope covers can be used, especially when the blade has movable parts.[5] Apart from ensuring no transfer of infection between patients, they can also serve to contain any dismembered parts, if the need arises. And thirdly, as always in anaesthetic practice, all unanticipated problems should be anticipated and a backup plan should be kept ready.
Figure 1