Nasal obstruction, epistaxis and olfaction

Definition / Overview

Nasal obstruction is one of the most frequent rhinologic complaints, encompassing a broad spectrum from intermittent unilateral blockage to fixed bilateral obstruction with significant impact on quality of life, sleep, and lower-airway health. Two structural causes dominate clinical practice:

• Septal deviation: asymmetric deflection of the cartilaginous or bony nasal septum, producing asymmetric airway cross-sectional area
• Turbinate hypertrophy: mucosal and/or bony enlargement of the inferior (or less commonly middle) turbinate, reducing the nasal airway independently or in conjunction with septal pathology

These two conditions co-exist in the majority of patients presenting for surgical evaluation, and their combined contribution to nasal resistance must be understood before any operative plan is formulated.

Anatomy Relevant to Surgical Planning

The Nasal Septum

The septum is a composite structure:

• Cartilaginous septum (quadrangular cartilage): forms the anterior, mobile segment; articulates inferiorly with the maxillary crest and nasal spine, superiorly with the perpendicular plate of the ethmoid and the nasal bones
• Bony septum: perpendicular plate of the ethmoid (superior) and vomer (posterior/inferior)
• Maxillary crest and palatine bone: form the floor attachment

Surgical landmark: the L-strut (dorsal and caudal 1-1.5 cm of septal cartilage) must be preserved to maintain nasal tip support and dorsal height. Loss of L-strut integrity risks saddle deformity and tip ptosis.

Structures at risk during septoplasty:

• Anterior ethmoidal artery (at the ethmoid roof during high posterior dissection)
• Sphenopalatine artery branches (posterior inferior septum)
• Olfactory epithelium (superior septum; limit dissection superiorly)
• Nasal mucoperichondrium (bilateral tears create risk of septal perforation)

Inferior Turbinate

The inferior turbinate is an independent bone (the largest of the three turbinates) covered by pseudostratified ciliated columnar epithelium richly supplied by capacitance vessels. Its blood supply derives from the lateral nasal branches of the sphenopalatine artery and branches of the anterior ethmoidal artery. The inferior turbinate head lies immediately posterior to the internal nasal valve.

Structures at risk during turbinate surgery:

• Nasolacrimal duct: runs laterally and inferiorly, opening beneath the inferior turbinate at the anterior end; aggressive anterior turbinate reduction risks nasolacrimal duct injury and epiphora
• Sphenopalatine artery branches: injury during posterior turbinate work causes significant haemorrhage
• Excessive tissue removal risks atrophic rhinitis (ozaena)

The Nasal Valve

• Internal nasal valve: the angle between the upper lateral cartilage and the septum ($\sim 10\text{-}15°$ in Caucasian noses); this is the site of maximum nasal resistance in the normal nose
• External nasal valve: the nostril aperture, bounded by the columella, alar rim, nasal floor and caudal septum

Nasal valve compromise must be identified preoperatively as it will persist after septoplasty if not specifically addressed.

Physiology: Nasal Airflow and the Nasal Cycle

Airflow Dynamics

Nasal airway resistance is governed by the Hagen-Poiseuille principle: resistance is inversely proportional to the fourth power of the airway radius. Small reductions in cross-sectional area cause disproportionate increases in resistance. At the internal nasal valve, laminar flow transitions toward turbulent flow, facilitating mucosal contact for humidification, warming, and filtration.

At the Venturi-narrow point of the internal nasal valve, accelerating airflow creates a negative intraluminal pressure, which can cause collapse of the compliant lateral nasal wall. This is clinically relevant in patients with weak upper lateral cartilages or a narrow valve angle.

The Nasal Cycle

The nasal cycle is an alternating, reciprocal congestion and decongestion of the capacitance vessels of the turbinates, primarily the inferior turbinate, driven by autonomic tone. The cycle period is approximately 2-4 hours. Total nasal resistance remains relatively constant as one side decongests while the other congests.

Paradoxical nasal obstruction arises in a patient with a fixed septal deviation. The deviated side has a permanently narrow but relatively fixed airway. The contralateral (open) side is subject to normal cyclic turbinate congestion. During the turgescent phase of the cycle on the open side, that side briefly narrows further and the patient perceives obstruction on their "better" side. This is a clinically important phenomenon because:

• The patient complains of blockage on the anatomically more patent side
• Examination at that moment shows inferior turbinate engorgement on the open side
• Misinterpretation may lead to turbinate reduction on the wrong side, or failure to address the underlying septal deviation

Aetiology and Classification

Septal Deviation

Turbinate Hypertrophy

Clinical Assessment

History

A structured history identifies the dominant component and guides management:

• Onset, duration, laterality: fixed unilateral suggests structural; bilateral alternating suggests turbinate/mucosal
• Associated symptoms: rhinorrhoea (nature: watery, mucoid, purulent), sneezing, post-nasal drip, anosmia, facial pain/pressure
• Seasonal or perennial pattern: supports or refutes allergic aetiology
• Snoring and witnessed apnoea: nasal obstruction contributes to mouth-breathing and may worsen sleep-disordered breathing
• Prior nasal trauma or surgery
• Drug history: antihypertensives (alpha-blockers cause rhinitis), oral contraceptive pill, regular intranasal decongestants
• Allergy history and skin-prick/RAST status
• Impact on quality of life: validated instruments (NOSE score, SNOT-22) provide baseline and postoperative outcome measurement

Examination

External:

• Skin: scars, prior surgical incisions
• Dorsum: deviation, saddle deformity, tip ptosis
• Alar rim: notching, collapse on inspiration (external valve)
• Modified Cottle manoeuvre: lateral cheek traction to open internal nasal valve; positive test (symptomatic relief) suggests internal valve compromise

Anterior rhinoscopy (nasal speculum):

• Caudal septal position: midline or deviated; visible dislocation off the maxillary crest
• Inferior turbinate size and colour: pale/boggy (allergic), erythematous (infectious/vasomotor)
• Mucosal quality; polyps
• Response to topical decongestant (1% lignocaine with adrenaline or oxymetazoline): if obstruction resolves, the turbinate mucosal component is dominant; if it persists, structural (bony or cartilaginous) causes predominate

Endoscopic examination (rigid 0° or 30° endoscope):

• Full assessment of septum along its length
• Middle meatus, ostiomeatal complex
• Nasopharynx (adenoid in children; postnasal mass in adults)
• Choanal patency
• Internal nasal valve angle assessment

Investigation

Routine

• Nasal endoscopy: mandatory for full septal and turbinate assessment
• NOSE score / SNOT-22: document symptom severity and enable audit of surgical outcomes
• Allergy testing (skin-prick or specific IgE): when allergic rhinitis suspected; critical before committing to turbinate surgery without addressing the underlying mucosal disease

Selective

• CT paranasal sinuses (coronal ± axial): indicated when sinusitis, nasal polyps, or structural complexity is suspected; demonstrates full extent of septal deviation including bony spur, reveals osteomeatal complex and associated sinus disease, identifies anatomical variants (concha bullosa, paradoxical middle turbinate, Haller cells)
• Acoustic rhinomanometry / anterior rhinomanometry: objective measurement of nasal airflow and resistance; useful for research, medicolegal documentation, and cases where subjective complaint and clinical findings are discordant
• Sleep study (polysomnography or home sleep apnoea test): when OSA is suspected; nasal obstruction alone rarely causes OSA but is a significant contributor to CPAP intolerance

Medical Management

Medical management must be optimised before surgical intervention is offered. The minimum trial period before considering surgery is typically 3 months.

Allergic and Inflammatory Rhinitis

• Intranasal corticosteroids (INCS): first-line for allergic rhinitis and turbinate hypertrophy driven by mucosal inflammation; reduce mucosal oedema and glandular secretion; minimal systemic absorption with modern fluticasone furoate, mometasone, or budesonide formulations; counsel on correct technique (away from septum to reduce perforation risk)
• Oral antihistamines (non-sedating): adjunct for sneezing and rhinorrhoea in allergic rhinitis
• Intranasal antihistamine (azelastine): faster onset than INCS; useful for PRN use
• Combination INCS + antihistamine sprays: superior efficacy in moderate-severe allergic rhinitis
• Nasal saline irrigation: reduces mucosal crusting, improves ciliary function, mechanically removes allergens
• Allergen immunotherapy (sublingual or subcutaneous): disease-modifying for allergen-driven turbinate hypertrophy; consider in motivated patients with proven sensitisation

Rhinitis Medicamentosa

• Cease offending decongestant: topical alpha-agonist withdrawal; bridging with INCS for 2-4 weeks facilitates cessation
• Warn patients of temporary rebound before improvement

Structural Causes

Medical therapy does not correct a deviated septum. However, INCS may sufficiently reduce concurrent turbinate hypertrophy to achieve acceptable symptom control and defer or avoid surgery in mild-to-moderate cases.

Surgical Management

Indications for Surgery

• Nasal obstruction refractory to adequate medical therapy (minimum 3 months)
• Documented structural cause on examination and/or imaging
• Significant impact on quality of life (elevated NOSE/SNOT-22)
• Recurrent epistaxis from septal spur contact (spur turbinate)
• Contributing to CPAP intolerance in OSA patients
• Associated recurrent or chronic rhinosinusitis where septal deviation compromises the ostiomeatal unit

Septoplasty

Principles

• Conservative resection and reshaping; preserve cartilage where possible
• Minimum L-strut of 1 cm dorsal and 1 cm caudal must be maintained
• Accurate submucoperichondrial dissection limits mucosal tears and reduces perforation risk

Surgical Steps (Standard Endonasal Approach)

1. Haemostasis: vasoconstriction with topical 1:1000 adrenaline pledgets or submucosal injection of 1% lignocaine with 1:100,000 adrenaline
2. Hemitransfixion incision (or Killian incision for more posterior deviations)
3. Unilateral submucoperichondrial flap elevation on the concave side, then contralateral flap on the convex side
4. Score or resect deformed cartilage (back-fracture, cross-hatching, morselisation); resect bony spur at its base
5. For caudal dislocation: swinging-door technique or caudal relocation suturing to the nasal spine periosteum
6. For high dorsal cartilaginous deviation: consider spreader grafts or spreader flaps to reconstitute the internal valve angle
7. Quilting suture or through-and-through mattress sutures to reappose mucosal flaps and obliterate dead space
8. Absorbable or removable splints/packs: reduce haematoma risk; bilateral splints maintain airway post-operatively

Complex Septal Deviation: Extracorporeal Septoplasty and Anterior Septal Reconstruction

For severe anterocaudal deviations that cannot be corrected with standard in situ techniques:

• Extracorporeal resection: entire cartilaginous septum is removed, straightened on the back table, and reinserted as a graft; risk of small step-deformity (notching) at the rhinion
• Anterior septal reconstruction (ASR): the deviated caudal septum is harvested, remodelled, and secured to a fixed dorsal strut graft; preserves dorsal support and minimises external deformity risk; preferred for severe caudal deflection

Endoscopic Septoplasty

Endoscopic assistance provides superior visualisation of the posterior septum and high deviations, with the ability to target specific points of obstruction with minimal mucosal disruption. Increasingly used as a complement to FESS when concurrent sinus surgery is undertaken.

Inferior Turbinate Reduction

Principles

• The goal is volume reduction while preserving mucociliary function and mucosa
• Aggressive reduction risks atrophic rhinitis: patient counselling is essential
• Address concurrent allergic rhinitis medically; turbinate surgery alone will not eliminate mucosal hyperresponsiveness

Techniques

Preferred approach in current practice: microdebrider-assisted turbinoplasty or RFA/Coblation under endoscopic visualisation; both provide durable results with low complication rates.

Nasal Valve Surgery

When preoperative assessment (positive modified Cottle, narrow valve angle on endoscopy) identifies internal nasal valve compromise:

• Spreader grafts: cartilage grafts placed between the upper lateral cartilage and the dorsal septum bilaterally to widen the internal valve angle; gold standard for functional internal valve reconstruction
• Spreader flaps (auto-spreader): folding of the upper lateral cartilage over the dorsal septum; avoids donor site harvest; effective when cartilage quality is adequate
• Flaring sutures: mattress sutures lateralising the upper lateral cartilages; adjunct technique
• Alar batten grafts: cartilage placed at the alar-sidewall junction to resist inspiratory collapse; address middle vault and external valve collapse

Failure to address nasal valve compromise at the time of septoplasty is the most common cause of persistent nasal obstruction after otherwise technically successful septal surgery.

Complications and Their Management

Intraoperative

Postoperative

• Septal haematoma: must be drained urgently (needle aspiration or incision) to prevent avascular necrosis of cartilage and abscess formation; septal splints and quilting sutures reduce risk
• Septal abscess: rare; IV antibiotics, surgical drainage, may result in significant cartilage loss
• Septal perforation: presents with crusting, epistaxis, whistling; small perforations may be managed conservatively with saline irrigation and petroleum jelly; large perforations require surgical repair (bilateral mucosal advancement flaps, septal button prosthesis)
• Saddle deformity: loss of dorsal support from inadequate L-strut preservation; requires reconstructive rhinoplasty
• Persistent nasal obstruction: re-evaluate for missed nasal valve pathology, residual deviation, turbinate hypertrophy, or new pathology
• Anosmia: rare; avoided by limiting superior dissection
• Toxic shock syndrome: rare but life-threatening; associated with nasal packing; minimise pack duration and consider prophylactic antibiotics per local protocol
• Nasolacrimal duct injury (turbinate surgery): epiphora; refer to ophthalmology; avoid aggressive anterior turbinate resection

Perioperative Considerations

Anaesthesia

• General anaesthesia with orotracheal intubation (throat pack to prevent blood aspiration) or laryngeal mask airway in selected cases
• Reverse Trendelenburg (head-up) positioning reduces intraoperative bleeding
• Hypotensive anaesthesia ($\text{MAP} \sim 60\text{-}70\,\text{mmHg}$) significantly reduces field bleeding during endonasal surgery; discuss with anaesthetist
• Vasoconstriction: submucosal injection of local anaesthetic with adrenaline is standard; allow adequate time ($\geq 5$ minutes) for effect before incision
• Topical cocaine (5-10%) or oxymetazoline pledgets provide additional vasoconstriction

Postoperative Care

• Nasal saline irrigation commencing within 24-48 hours post-operatively; continue for minimum 4-6 weeks
• Avoid nasal trauma, nose-blowing, and vigorous exercise for 2 weeks
• Splints removed at 7-10 days if used
• INCS resumed at 2-4 weeks post-operatively to reduce mucosal recurrence
• Warn patients that full benefit may not be apparent for 6-12 weeks as mucosal swelling resolves
• NOSE score reassessment at 3 and 12 months to audit outcomes

Special Populations

• Children: septoplasty is generally deferred until skeletal maturity (late adolescence) to avoid disruption of nasal growth centres; however, severe symptomatic deviation (obstructive sleep apnoea, sinusitis, feeding difficulties in infants) justifies earlier conservative intervention
• Anticoagulated patients: liaise with prescriber; bridge anticoagulation peri-operatively according to indication and thromboembolic risk; aspirin cessation 7-10 days pre-operatively reduces turbinate haemorrhage risk
• Pregnant patients: medical management preferred; surgery deferred to postpartum except for life-threatening airway compromise

Evidence Base and Outcome Data

• Septoplasty with concurrent turbinate surgery is superior to non-surgical management for nasal obstruction, with sustained improvements in disease-specific quality of life and objective airflow measures at 12 and 24 months in randomised controlled trial evidence
• Failure to address nasal valve pathology at initial surgery is the leading surgically correctable cause of poor septoplasty outcomes; mandates systematic valve assessment in all pre-operative evaluations
• Radiofrequency turbinate reduction and microdebrider turbinoplasty have equivalent efficacy at 12 months in comparative series; choice depends on surgeon preference and available equipment
• NOSE score $\geq 55$ (moderate-to-severe) correlates with patient willingness to undergo surgery and is a reasonable threshold for operative referral in the context of adequate medical treatment failure

Key Examination Points

• Paradoxical nasal obstruction: patient complains of blockage on the anatomically open side; occurs during turgescent phase of nasal cycle on that side; do not reduce the turbinate on the open side without addressing the septal deviation
• L-strut preservation: dorsal 1 cm + caudal 1 cm; violation causes saddle and tip deformity
• Internal nasal valve: angle between upper lateral cartilage and septum; most common site of residual obstruction after septoplasty if not assessed and addressed
• Septal haematoma: surgical emergency; drain immediately to prevent cartilage necrosis and abscess
• Atrophic rhinitis risk: excessive turbinate removal; preserve mucosal lining; prefer submucosal volume reduction techniques
• Nasolacrimal duct: at risk with aggressive anterior inferior turbinectomy