Anaesthetic Management of Post COVID-19 Mucormycosis of the eye with Cerebral Abscess

Introduction

A 57-year-old male suffering from invasive rhinocerebral mucormycosis with right orbital extension and right temporal lobe abscess was electively posted for surgical management. There was history of swelling of right temporal region for 15 days and swelling and redness of right eye for four months with pain and gradual diminution of vision. There was no history of trauma, fever, headache, cough or vomiting. He was a known case of ischemic heart disease (on aspirin, 75mg), hypertension (on amlodipine, 5mg OD) and type 2 diabetes mellitus (on metformin 500mg and glimepiride 1mg, both once per day).

It was revealed that the patient was admitted for COVID-19 infection three months ago for 15 days with right eye cellulitis and lateral rectus palsy. Before admission, he was under ophthalmologic care for diminished vision, redness and pain in right eye for a week and tested positive for SARS-CoV-2 by reverse transcriptase polymerase chain reaction (rTPCR). Bilateral acute maxillary and ethmoidal sinusitis was diagnosed based on computerized tomography. Potassium hydroxide (KOH) mount of the eye by the ophthalmologist was negative for fungal elements. The patient received antibiotics (topical and IV), oral linidazole, fluconazole, metronidazole, acetazolamide, oxygen, inj. dexamethasone - 4mg twice daily, enoxaparin, and soluble insulin. On discharge, patient was advised antibiotics, bio nutrients and rivaroxaban.

Four days after discharge from COVID-19 hospital, he had visited another hospital on his own for persistent eye symptoms and was diagnosed to be suffering from invasive rhinocerebral mucormycosis with involvement of right eye. He underwent endoscopic debridement, right optic nerve decompression and excision of fungal mass under general anaesthesia. He was advised inj. amphotericin B for a period of 14 days post operatively. After two months of apparent improvement, he developed increasing vision disturbances and presented to our hospital. Patient was conscious, well oriented with pulse oximetric oxygen saturation of 98% on room air. The pulse rate, blood pressure and airway assessment were normal. Fine crepitations were heard in lower zones of both lungs.

Patient had hemoglobin (Hb) of 7.7 gm/dl and he received transfusion of two units of packed red blood cells three days prior to surgery. The Hb improved to 11.8 gm% on preoperative day. The r-TPCR for COVID-19 was negative; the total leucocyte count was 8000 cells/ mm3 . Platelet count, prothrombin time, activated partial thromboplastin time, sugar profile, renal and liver function tests were within normal limits. Electrocardiogram showed old ischemic changes in anterior leads. Chest X ray showed increased broncho vesicular markings. 2D echocardiogram revealed residual wall motion abnormalities (WMAs) (akinesia of anterior segments), moderately dilated left ventricle with left ventricular ejection fraction (EF) of 40%. Magnetic Resonance Imaging (MRI) revealed (Figure 1) altered shape of right globe, proptosis, ill-defined, thickened optic nerve & extraocular muscles, temporal lobe involvement and midline shift.

Patient was put on intravenous phenytoin sodium for four days preoperatively. Aspirin was stopped three days before surgery. Patient’s blood glucose levels were stabilized with soluble insulin two days before surgery; fluconazole and amlodipine were continued. Nebulization with bronchodilators was advised. Written informed consent was obtained and general anaesthesia with endotracheal intubation was planned. Routine pre-anaesthesia check-up drill was performed and basal parameters were noted. After pre-oxygenation, inj. fentanyl and preservative free lignocaine was administered; anaesthesia was induced with inj. etomidate and vecuronium. Right eye appeared bulged with cellulitis (Figure 2) and adequate padding was ensured. Trachea was intubated with no.9 mm cuffed disposable oral endotracheal tube and confirmed with square wave capnographic tracing. Patient was maintained on nitrous oxide, oxygen and propofol infusion with controlled ventilation and positive end expiratory pressure of 5mm Hg. Surgical procedure included abscess drainage by cranial burr hole, evisceration of the eye and lasted for 90 minutes. Intraoperatively, 600ml of Ringer’s lactate was infused. Trachea was extubated after neuromuscular block reversal with neostigmine and glycopyrrolate. Recovery was satisfactory and patient was shifted to post anaesthesia care unit. He spent an uneventful five days in the wards and was discharged.

Discussion

Majority of COVID-19 patients are symptom free but others may suffer from mild to severe disease.¹ The morbidity and mortality are likely to be more in those with reduced immunity, including elderly patients and those with co-morbid conditions such as diabetes mellitus.² The patients receive steroids to prevent or mitigate the severe inflammatory response that may precipitate lung or other organ injury.³

Co-infections at the time of diagnosis and development of superinfections can be expected in some patients.⁴ The patient described here had symptoms involving eye for one week and was detected to be positive for COVID-19 during investigations. The factors that may have contributed to the development of fungal infection could be the diabetic state, use of steroids and broadspectrum antibiotics after admission. COVID-19 is also associated with worsening of dysglycemia and diabetes mellitus.⁵ The patient here had not received tocilizumab, a monoclonal antibody known to increase risk of infections and neither he received any steroids post COVID-19. The sinusitis and cellulitis of the eye improved after antibiotic and antifungal treatment. However due to persistence of eye symptoms post discharge, he was diagnosed to have invasive rhinocerebral mucormycosis at a different hospital where he underwent surgical procedure. After being asymptomatic for two months, the symptoms reappeared and this led to current admission and surgical treatment again.

Post COVID-19 patients with comorbid conditions need long term monitoring for risk of developing numerous manifestations.⁶ Opportunistic infections including fungal infections can also manifest because of diabetes mellitus.^7,8 Mucormycosis is associated with a poor prognosis and early detection and management is required as it is a fungal emergency with a highly aggressive tendency for contiguous spread. Early diagnosis may be missed in COVID-19 as the focus is on retrieving the patient. The mycosis was probably a coinfection in our case which became full blown later on. Mucormycosis involving the nose, paranasal air sinuses, eyes, lungs and brain in association with COVID-19 have been reported.^9-11

In the present case, patient’s pulmonary, liver, renal and coagulation parameters were found to be normal. Diabetic state was controlled with soluble insulin preoperatively. Post COVID-19 lung fibrosis is a risk, which may be self-limiting or progressive.¹² Anaemia was diagnosed to be of nutritional origin and along with supplements of iron, packed cells were infused carefully based on the considerations of bleeding and risk of fluid overload. Patient had significant WMAs of anterior wall of left ventricle, with EF of 40%. Measures to prevent cardiovascular lability were taken during intubation with use of lignocaine IV and etomidate and during maintenance with the use of propofol infusion as the background anaesthetic. Elective surgeries post SARSCoV-2 infection are recommended to be performed after minimum of 7 weeks as mortality rates may be higher if performed early. In the presence of symptoms, this duration may need to be extended further.¹³ Our patient was in 11th week post COVID-19 and adequate precautions were taken in preoperative assessment, preparation and anaesthetic management.

Conclusion

SARS-CoV-2 infection can cause relentless pathological insults with high mortality and morbidity. No organ is spared; secondary bacterial and fungal infections may be precipitated during the disease stage. Diabetes mellitus may also contribute to invasive infections such as mucormycosis with significant morbidity in post COVID-19 period. Adequate work up can help in successful surgical and anaesthetic management of such invasive infections.

Conflict of Interest

None.