Airway challenges posed by tongue injuries following neurosurgical procedures in prone position

Amruta Mihir Kulkarni; Vijay L Shetty

doi:10.4103/arwy.arwy_53_21

CASE REPORT

Year : 2022 | Volume : 5 | Issue : 1 | Page : 40-44

Airway challenges posed by tongue injuries following neurosurgical procedures in prone position

Amruta Mihir Kulkarni, Vijay L Shetty
Department of Anaesthesia, Fortis Hospital, Mulund, Maharashtra, India

Date of Submission	17-Sep-2021
Date of Decision	27-Oct-2021
Date of Acceptance	03-Nov-2021
Date of Web Publication	17-Jan-2022

Correspondence Address:
Dr. Amruta Mihir Kulkarni
Department of Anaesthesia, Fortis Hospital, Mulund, Mumbai, Maharashtra
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/arwy.arwy_53_21

Abstract

Safe patient position is an important aspect of anaesthesia care. Prone position during neurosurgery may be associated with airway oedema or complications such as tongue injuries or swelling. Prevention of such morbidities with proper planning, meticulous positioning, continuous vigilance, early diagnosis and aggressive treatment are crucial. We describe the perioperative events of three patients who presented with tongue-related morbidity following neurosurgical procedures in the prone position where one developed tongue haematoma and other two had macroglossia in the postoperative period. The patient with haematoma was asymptomatic and required no intervention apart from reassurance about the self-resolving nature of haematoma. Two patients with macroglossia were kept intubated, nursed in head-up position and administered intravenous steroids and local antidesiccants. One patient required tracheostomy while the other could be extubated 48 h postoperatively. Vigilance, prompt diagnosis and appropriate management improved overall outcome.

Keywords: Macroglossia, neurosurgery, prone position, tongue injury

How to cite this article:
Kulkarni AM, Shetty VL. Airway challenges posed by tongue injuries following neurosurgical procedures in prone position. Airway 2022;5:40-4

How to cite this URL:
Kulkarni AM, Shetty VL. Airway challenges posed by tongue injuries following neurosurgical procedures in prone position. Airway [serial online] 2022 [cited 2023 Sep 21];5:40-4. Available from: https://www.arwy.org/text.asp?2022/5/1/40/335896

Introduction

Improper positioning of the patient under anaesthesia has been shown to result in neurological and musculoskeletal complications.^[1] Excessive flexion or rotation of head and neck may reduce the blood flow in vertebral and carotid arteries. The resultant ischaemia of the brain stem and cervical spine can cause quadriparesis or quadriplegia. Excessive neck flexion may also cause obstruction to the lymphatic and venous drainage, resulting in oedema of the face, neck, tongue and airway causing airway obstruction.^[1] Injury and swelling of the tongue can occur when prone position is used in neurosurgery to facilitate approach to the posterior fossa, suboccipital region and spine surgeries.^[1] Inadequate padding may cause direct compression and undue stretching may lead to nerve ischaemia, both manifesting as peripheral nerve injuries.^[2]

Case Reports

Case 1

A 36-year-old female diagnosed with an intradural D₁₂-L₃ myxopapillary ependymoma was scheduled for excision of lesion in the prone position with intraoperative neuromonitoring (IONM) in the form of somatosensory evoked potentials (SSEP) and motor evoked potentials (MEP). General anaesthesia was administered, with considerations for SSEP and MEP monitoring. Throat pack and bilateral intermolar soft gauze bite block were inserted. Prone position was given with head supported on a foam head pillow with cut-out and padding of all pressure points. The tumour was excised completely with no adverse manifestations in IONM. The patient noticed a painless haematoma on the under surface of the tongue on the 2^nd postoperative day. She was reassured about the self-resolving nature of the haematoma. The haematoma completely resolved on the 6^th postoperative day [Table 1].

Table 1: Summary of patient demographics, intraoperative and postoperative events

Click here to view

Case 2

A 47-year-old female with paraplegia following road traffic accident was posted for occipito-cervical stabilisation and C₁-C₂ fixation. She received general anaesthesia with endotracheal intubation and was positioned prone with the head supported on a horse-shoe. Macroglossia was noted as soon as the patient was made supine. Antagonism of residual neuromuscular blockade and extubation were deferred and she was shifted to the intensive care unit (ICU). She was nursed in the head-up position and placed on control mode ventilation to minimise movements of the tongue and allow the tongue oedema to subside expeditiously. Steroids were continued, bilateral bite blocks were inserted and the tongue covered with a wet gauze to prevent drying. She had a surgical tracheostomy done on 4^th postoperative day and the tongue swelling gradually resolved [Table 1].

Case 3

A 7-year-old-girl with complaints of headache and vomiting was diagnosed (post-magnetic resonance imaging) to have medulloblastoma of roof of 4^th ventricle with tonsillar herniation. She was posted for suboccipital craniotomy with excision of medulloblastoma in the prone position with IONM in the form of SSEP and MEP. The child was administered general anaesthesia with endotracheal intubation. Throat pack and bilateral soft bite blocks were inserted. The child was placed in the prone position with head fixed on Mayfield skull clamp. Intraoperative course was uneventful and the tumour excised without any change in IONM. Following a 12-h surgery, the child was shifted to the paediatric ICU for elective ventilation. Macroglossia was noted an hour postoperatively in the ICU. It was managed with nursing in propped-up position, steroids, cold compression of tongue at intervals and wet gauze to prevent dessication of the protruding tongue. The tongue swelling decreased over 48 h and the child was extubated on postoperative day 3, shifted to the ward on postoperative day 5 and later discharged with no deficit [Table 1] and [Figure 1].

Figure 1: Macroglossia in 7-year child following suboccipital craniotomy for excision of medulloblastoma

Click here to view

Discussion

We present three patients, one with tongue haematoma and two with macroglossia following neurosurgical procedures in the prone position.

Prone position is associated with changes in haemodynamics and respiratory mechanics.^[2] Prone position must be provided carefully with appropriate support and padding of pressure points. The endotracheal tube must be firmly secured to prevent displacement.^[2] Excessive flexion of the neck may cause stress on arteries and veins of brain and cervical spinal cord. It is recommended to keep 2–3 finger breadth gap between the chin and sternum during neck positioning.^[1] We had ensured the same in all three patients.

IONM was used in the first and third case. Neuromuscular blocking agents (NMBA) were avoided after induction to facilitate neuromonitoring. Bite injury is a known complication when NMBAs are avoided with an incidence of 0.63%.^[3] Transcranial stimulation for MEP causes clenching of jaw by various mechanisms increasing the risk of bite injuries. Tamkus and Rice suggested the high intensity stimulus and possible displacement of bite blocks increased bite injuries.^[3] They recommended the use of properly sized, secured bite block with periodic inspection to decrease bite injuries.^[3] Hao et al. and Williams and Singh have also suggested use of soft bite blocks in patients undergoing intraoperative MEP monitoring.^[4],[5] We had used soft rolled-gauze bite blocks bilaterally in between the molars in both the patients.

Oropharyngeal swelling consisting of macroglossia and salivary gland swelling is a known complication of prolonged surgery in the prone position.^[6] The aetiology of macroglossia is multifactorial.^[6],[7]

Regional venous and lymphatic obstruction, and kinking of salivary ducts due to prolonged excessive neck flexion or external compression
Local mechanical compression of tongue
Regional venous thrombosis
Reperfusion injury
Dependent oedema due to effect of gravity and excessive intravenous fluid administration
Traumatic oedema or neurogenic oedema due to surgical manipulation of brain stem in some patients
Oral objects such as endotracheal tube, airway and throat pack may cause local compression

Various aetiologies mentioned above may impede the venous and lymphatic drainage of the tongue leading to swelling of the tongue. Reperfusion injury occurs when compression of the lingual artery either due to venous/lymphatic obstruction or due to external compression is relieved, and the arterial flow begins.

Macroglossia that is mild with immediate onset is usually due to local venous or lymphatic congestion. When severe, it is usually related to reperfusion injury.^[8] In our second patient, macroglossia was noticed in the immediate postoperative period, whereas reperfusion injury was the possible causative mechanism in the third patient where macroglossia developed 1 h after shifting from the operation theatre. In a review article, Brockerville et al. suggested that the incidence of macroglossia is more in neurosurgery lasting more than 8 h, surgery done in prone position and following posterior fossa craniotomies.^[7]

Macroglossia may be treated with upright position to facilitate venous drainage, steroids to reduce oedema, regular tongue massage, wet gauze to prevent dessication of the tongue and insertion of bite blocks to relieve pressure on tongue.^[7],[9] The patient should be kept intubated once tongue oedema is noticed as airway management may be difficult once oedema develops or begins to worsen. In patients with suspected swelling, air leak must be checked by deflation of cuff before extubation.^[2] Both our patients with macroglossia were kept intubated, nursed in upright position, received intravenous steroids and cold compression with covering of the protruding tongue. Our second patient required tracheostomy but in our third patient, the child could be extubated 48 h after surgery.

Macroglossia is a disturbing complication that can be prevented by various methods. The head should be maintained in neutral position with proper head and neck support to prevent full flexion.^[6] Compression of the tongue should be avoided.^[6],[7] Nasal intubation may be considered but may be limited to cases where a head clamp is used. A rigid oral airway may cause compression and a soft bite block must be placed in between the molars on either side to keep the mouth slightly open.^[7] The duration of surgery should be limited to prevent prolonged prone position increasing risk of complications.^[10] In all our patients, head position was provided taking care to avoid excessive neck flexion or rotation. Bilateral bite blocks were inserted in both the patients in whom IONM was planned to keep the mouth in the open position. While regular monitoring of the head, neck and tongue is suggested, it may be difficult in neurosurgical cases as access is limited.

Conclusion

Prone position is essential for certain neurosurgical procedures, but must be given with utmost care to minimise associated complications. Though rare, macroglossia and tongue injury are known complications in the prone position. Surgical duration should be minimised or a staged procedure must be considered to reduce complications. The head must be kept in neutral position. A bite block between the molars on both sides made from soft rolled gauze must be used to prevent macroglossia as well as risk of bite injury in patients undergoing IONM. Through our experiences, we wish to highlight the risk factors, need for vigilance, the dangers and the treatment of postoperative tongue injury and major swelling.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the forms, the patients/patient's legal guardian have given consent for images and other clinical information to be reported in the journal. The patients/legal guardian understand that the names and initials of patients will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Rozet I, Vavilala MS. Risks and benefits of patient positioning during neurosurgical care. Anesthesiol Clin 2007;25:631-53.
2.	Edgcombe H, Carter K, Yarrow S. Anaesthesia in the prone position. Br J Anaesth 2008;100:165-83.
3.	Tamkus A, Rice K. The incidence of bite injuries associated with transcranial motor-evoked potential monitoring. Anesth Analg 2012;115:663-7.
4.	Hao TJ, Liu G, Ang P. A rare complication of tongue laceration following posterior spinal surgery using spinal cord monitoring: A case report. Indian J Anaesth 2014;58:773-5. [PUBMED] [Full text]
5.	Williams A, Singh G. Tongue bite injury after use of transcranial electric stimulation motor-evoked potential monitoring. J Anaesthesiol Clin Pharmacol 2014;30:439-40. [PUBMED] [Full text]
6.	Kwee MM, Ho YH, Rozen WM. The prone position during surgery and its complications: A systematic review and evidence-based guidelines. Int Surg 2015;100:292-303.
7.	Brockerville M, Venkatraghavan L, Manninen P. Macroglossia in neurosurgery. J Neuroanaesthesiol Crit Care 2017;4:78-84. [Full text]
8.	Lam AM, Vavilala MS. Macroglossia: Compartment syndrome of the tongue? Anesthesiology 2000;92:1832-5.
9.	Moore JK, Chaudhri S, Moore AP, Easton J. Macroglossia and posterior fossa disease. Anaesthesia 1988;43:382-5.
10.	Ababneh O, Alghanem S, Al-Shudifat A, Khreesha L, Obeidat S, Bsisu I. Acute macroglossia post craniotomy in sitting position: A case report and proposed management guideline. Int Med Case Rep J 2020;13:391-7.