Discussion

Eustachian tuboplasty is a relatively safe procedure, with a risk of major complications of less than 1 per cent,^{Reference Meyer, O'Malley, Schlosser, Soler, Cai and Hoy8,Reference Ramakrishnan, D'Souza and Kadambi9} although adverse events have been reported (e.g. nose bleeds, pain, patulous Eustachian tube, soft tissue emphysema, hypoglossal paresis and transient dysesthesia of the tongue). The most common risk is failure of the procedure.^{Reference Ramakrishnan, D'Souza and Kadambi9} We also found two reported cases of pneumomediastinum; both cases were also managed conservatively.^{Reference Long, Obayemi and Rameau10,Reference Shah, Thomas, Naples and Ruckenstein11} Very recently, our anaesthesia colleagues from South Korea reported a case of transient asystole. Our colleagues thought this occurred because of stimulation of the vagal or glossopharyngeal nerve, thus triggering the trigemino-cardiac reflex. Fortunately, the condition was transient; nevertheless, it is advisable to build up pressure in the balloon slowly.^{Reference Chung, Shin, Cha and Lee12}

Like others, surgical emphysema has been mentioned as a frequent complication in the literature, but most cases reflect minor mucosal tears. Most of the cases were reported within 3 days. They were either related to repeat procedures, or post-operative Valsalva manoeuvre or heavy weightlifting.^{Reference Ramakrishnan, D'Souza and Kadambi9,Reference Jang and Yuen13} Consequently, most of the review articles have suggested avoiding the Valsalva manoeuvre in the immediate post-operative period.^{Reference Long, Obayemi and Rameau10,Reference Shah, Thomas, Naples and Ruckenstein11} A similar situation occurred in our case – the patient was not advised to avoid Valsalva manoeuvres, rather he thought a Valsalva manoeuvre was acceptable if he experienced a feeling of obstruction, which consequently resulted in this complication. Controversy exists in this regard and some clinicians will recommend Valsalva manoeuvre in the immediate post-operative period.^{Reference McMurran, Hogg, Gordon, Spielmann and Jones14} Our colleagues from Scotland have suggested that the symptom control rate is better in those groups who perform Valsalva manoeuvre post balloon Eustachian tuboplasty as compared to those who do not.^{Reference McMurran, Hogg, Gordon, Spielmann and Jones14}

Unlike previously published cases, our patient presented with extensive surgical emphysema on the 5th post-operative day while he was performing the Valsalva manoeuvre. Fortunately, the mediastinum was not involved. As the procedure was conducted in another, distant hospital, the exact type and brand of the balloon, and the specific procedural technique remained unknown. We feel it might have been useful to know how long the balloon was inflated for and whether were there any failed attempts during the catheter insertion.

As in other cases, our patient was admitted to the ENT department for conservative management. Cervicofacial and mediastinal emphysema is usually self-limiting. However, in certain circumstances, it can lead to severe soft tissue infections, and even lead to mediastinitis and sepsis.^{Reference Perna, Vilà, Guelbenzu and Amat15} A study on balloon Eustachian tuboplasty catheter tips found a wide range of bacterial species, including the normal flora of pharyngeal mucosa (e.g. Corynebacterium, Staphylococcus hominis, Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis, Escherichia coli, Streptococcus pyogenes and Klebsiella oxytoca).^{Reference Schröder, Abdel-Aziz, Lehmann, Ebmeyer and Sudhoff16} Our patient's swab findings do suggest the potential risk of bacterial infection in the sterile peri-tubal tissues and soft tissue compartments of the head, neck and mediastinum. Infection can intercommunicate freely, especially in cases of rupture of the mucosal layer, as suspected in cases of cervicofacial and mediastinal emphysema following balloon Eustachian tuboplasty.^{Reference Skevas, Dalchow, Euteneuer, Sudhoff and Lehnerdt17} Hence, the use of broad-spectrum antibiotics covering both Gram-positive and Gram-negative bacteria seems essential in the event of complications. We used amoxicillin with clavulanic acid in our case.

Although balloon Eustachian tuboplasty is a safe procedure, complications may go unreported. Our case highlights an important complication of balloon Eustachian tuboplasty. Skevas et al. conducted a study in which 10 patients had post-operative cervicofacial emphysema, but pneumomediastinum developed in only 3 of them.^{Reference Skevas, Dalchow, Euteneuer, Sudhoff and Lehnerdt17} In that study, the post-operative emphysema rate was 0.27 per cent. The authors recommended avoiding the Valsalva manoeuvre for 2–6 days post-operatively, and all patients were managed conservatively without any serious signs or symptoms.^{Reference Skevas, Dalchow, Euteneuer, Sudhoff and Lehnerdt17}

Similarly, Luukkainen et al. conducted a systemic review of five studies with complication rates of 0.3–21 per cent.^{Reference Luukkainen, Kivekäs, Silvola, Jero and Sinkkonen18} Howard et al. concluded that balloon Eustachian tuboplasty was a relatively safe intervention, with an overall complication rate of 4.7 per cent in a paediatric population.^{Reference Howard, Babu, Haupert and Thottam19} Although numerous studies have been published on the efficacy and outcome of balloon Eustachian tuboplasty, our literature search indicates that there is paucity of literature regarding the precise rates of possible major complications. Hence, we suggest that further research is required in this area.