Adapting to the unadaptable: Anaesthetic management in patients with coexisting challenges of positioning and difficult airway for cataract surgery

INTRODUCTION

Cataract surgery is most commonly performed under regional anaesthesia, which provides reliable analgesia and akinesia and is well tolerated by the majority of patients.[1] The procedure is typically carried out in the supine position and, in many standalone eye centres, is safely performed without the routine presence of an anaesthesiologist.

While this approach works well for the majority, specific patient populations pose positioning challenges that require creative solutions. Conditions such as severe kyphoscoliosis, ankylosing spondylitis, and post-radiation cervical fibrosis can prevent patients from assuming the standard supine position.[2,3]

Several innovative surgical adaptations for such patients have been described, including face-to-face phacoemulsification and standing phacoemulsification.[4,5,6] However, anaesthetic considerations receive comparatively little attention, despite anaesthesiologists’ intervention being required in 21–37% of cases.[7]

A particularly challenging scenario arises when a difficult positioning coexists with a difficult airway. In routine cataract surgery under peribulbar block, even though general anaesthesia is never the primary plan, the anaesthesiologist operates with an implicit reassurance: Should a complication arise, such as the oculocardiac reflex, local anaesthetic systemic toxicity (LAST), or uncontrollable surgical pain, the airway can be secured to manage the situation. When airway rescue is anticipated to be difficult or impossible, this safety margin is lost. The stakes of every decision are amplified, vigilance must be heightened, and emergency preparedness must be comprehensive.

We present two cases in which patients with different positioning challenges shared the compounding problem of a coexisting difficult airway. Both cases were managed at a tertiary standalone ophthalmic institute with a state-of-the-art modular operating theatre and full emergency backup. We aim to highlight the anaesthesiologist’s perspective, particularly the concept of a “lost safety net” and practical strategies for managing such complex scenarios.

CASE REPORTS

Case 1: A 55-year-old male presented for right eye cataract surgery. He had been treated for carcinoma of the lower alveolar ridge one year earlier and had completed 12 cycles of chemotherapy. Pre-anaesthetic evaluation revealed severe post-radiation fibrosis with restricted mouth opening limited to one fingerbreadth, excessive oral secretions, and a Ryle’s tube in situ for nutritional support [Figure 1a and b]. The patient could not lie flat and tolerated only a 30–45° propped-up position.

Figure 1.

Case 1 – Post-radiation trismus patient. (a) Patient demonstrating restricted mouth opening secondary to post-radiation fibrosis; (b) Mouth opening limited to one finger breadth with Ryle’s tube in situ; (c) Peribulbar block administered in 45° propped-up position; (d) Surgery performed with the operating table elevated at 45°, with the surgeon using a footstep for optimal microscope alignment

The patient’s vital signs were stable [blood pressure (BP) 100/60 mmHg, pulse 84/min, peripheral oxygen saturation (SpO₂) 100% on room air]. Echocardiography showed preserved left ventricular function; chest radiography was unremarkable.

From an anaesthetic standpoint, the patient posed two major concerns: inability to assume the supine position and an anticipated difficult airway. Although peribulbar block was the preferred anaesthetic technique, the restricted mouth opening severely limited options for emergency airway management. Sedation was avoided entirely as even minimal respiratory depression could precipitate airway obstruction with limited rescue options.

Comprehensive emergency preparedness was ensured. A difficult airway cart, video laryngoscope, fibreoptic bronchoscope, and emergency tracheostomy equipment were kept ready. Emergency drugs, including atropine, adrenaline, and succinylcholine, were readily available. The surgical team was briefed regarding the possibility of aborting the procedure if airway compromise occurred.

Standard monitoring was instituted, and a 22-G intravenous cannula was secured. A peribulbar block was administered via an inferotemporal approach with the patient’s head elevated at 45° [Figure 1c] using a mixture of 2% lignocaine and 0.5% ropivacaine (total volume 6 mL). A suction apparatus was kept available.

Given the dense cataract, small-incision cataract surgery with intraocular lens implantation was planned. Surgery was performed with the operating table maintained at 45-degree head elevation while the surgeon utilised a footstep to achieve adequate positioning relative to the operating microscope [Figure 1d]. The 45-degree head elevation necessitated significant adaptations: The irrigation bottle had to be elevated to maintain anterior chamber depth, and microscope adjustments were required for optimal visualisation. Vitals remained stable throughout, and surgery was completed uneventfully.

Case 2: A 59-year-old wheelchair-bound male with a hard cataract was scheduled for left eye cataract surgery. He had suffered a cerebrovascular accident 6 years earlier and had residual hemiplegia and controlled hypertension on telmisartan 40 mg daily. He was on aspirin 75 mg daily, which was continued perioperatively.[8]

Examination revealed severe kyphoscoliosis, precluding supine positioning [Figure 2a]. The spinal deformity also raised concerns regarding mask ventilation, laryngoscopy, and intubation in an emergency. Pre-operative vitals were stable (BP 140/80 mmHg, pulse 78/min, SpO₂ 100% on room air). Echocardiography showed preserved ventricular function with mild valvular regurgitation and pulmonary hypertension; chest radiography revealed hyperinflated lungs.

Figure 2.

Case 2 – Kyphoscoliosis with the hemiplegia patient. (a) Patient unable to lie flat due to severe kyphoscoliosis; (b) Positioning achieved with folded bed sheets overhead ring and pillow support; (c) Face-to-face peribulbar block technique with the anaesthesiologist facing the patient; (d) Surgery performed with a tilted operating microscope and the surgeon in the lateral position using a superotemporal approach

Medical fitness for surgery under local anaesthesia was obtained. Multiple positioning strategies were trialled. Folded bed sheets over the head ring and lateral pillows for support achieved a tolerable near-supine position [Figure 2b], guided by the patient’s habitual sleeping posture documented preoperatively.

Standard monitoring was instituted, and a 22-G intravenous cannula was secured. A peribulbar block was administered using a face-to-face approach, with the anaesthesiologist positioned in front of the patient rather than at the head end [Figure 2c]. The head was stabilised using strapping to maintain alignment. The same anaesthetic mixture as in Case 1 was used.

Surgical modifications included tilting of the operating microscope, and the surgeon adopted a lateral sitting position using a superotemporal approach [Figure 2d]. Emergency airway equipment and drugs were kept available. The procedure was completed uneventfully, with stable intraoperative haemodynamics.

DISCUSSION

These cases illustrate a clinically significant but underreported scenario: the convergence of positioning challenges with a coexisting difficult airway during cataract surgery under regional anaesthesia. While peribulbar block remains the standard technique for cataract surgery, the anaesthesiologist’s confidence during regional anaesthesia rests partly on the assumption that airway rescue is feasible if required. When this assumption no longer holds, the anaesthesiologist operates without a safety margin, a situation we describe as a “lost safety net”. This concept has important implications. Sedation becomes contraindicated, monitoring must be meticulous, emergency preparedness exhaustive, and the threshold for aborting surgery lower.[9]

Although the literature describing surgical adaptations for non-supine cataract surgery is expanding,[2,3,4,5,6] anaesthetic perspectives remain limited. In Case 1, post-radiation trismus was not a positioning issue per se, but it critically altered anaesthetic risk as up to 55% of such patients present with difficult intubation.[10] Severe mouth opening restriction necessitated avoidance of sedation and heightened emergency readiness.

In Case 2, kyphoscoliosis caused both positioning difficulty and compromised airway access. The combination of positioning aids with a face-to-face block technique enabled safe block administration without specialised equipment.

Administering a peribulbar block in non-supine positions introduces technical challenges. In face-to-face approaches, altered globe-orbit relationships and gravitational sag may increase the risk of globe perforation, reported at 1 in 2000 to 1 in 5000 cases.[11,12] Such blocks should be performed only by experienced practitioners capable of adapting needle trajectory to altered anatomy.

Several practical lessons emerge. A detailed history of habitual sleeping positions can guide intraoperative positioning. Trial positioning and draping during pre-anaesthetic evaluation help assess tolerance and reduce anxiety. Infrastructure, including adjustable operating tables and adequate ceiling height for irrigation bottle elevation, is crucial. Above all, clear communication between surgeons and anaesthesiologists is essential for coordinated planning and real-time decision-making.

CONCLUSION

Peribulbar block remains the standard anaesthetic technique for cataract surgery. However, when positioning challenges coexist with a difficult airway, the anaesthesiologist must recognise that the implicit safety net of emergency airway rescue is compromised. With meticulous pre-operative assessment, avoidance of sedation in high-risk airways, comprehensive emergency preparedness, and close collaboration between anaesthesiologists and surgeons, even patients with complex positioning and airway challenges can undergo cataract surgery safely and successfully.

Declaration of patient consent

Written informed consent was obtained from both patients for publication of these case reports and accompanying images.

Study data availability

All data relevant to this clinical communication are included within the article. No additional datasets were generated or analysed.

Disclosure of use of artificial intelligence (AI)-assistive or generative tools

AI-assistive tools were used only for literature search. The manuscript was conceptualised, drafted, and revised entirely by the authors, who take full responsibility for its content.

Author contributions

SR: Conceptualisation and manuscript design, data acquisition, anaesthesia management, literature review, manuscript drafting, critical revision for intellectual content, and final approval of the version to be published. JVV: Conceptual guidance, supervision, critical revision of the manuscript for academic and clinical relevance, and final approval. M Nicholson: Surgical management of cases, contribution to clinical details, critical revision of the manuscript from the surgical perspective, and final approval. M Naik: Surgical management of cases, contribution to operative details, and final approval.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.