Orbital exenteration under trigeminal block: An innovative method of regional anesthesia
A 68-year-old male patient was admitted with complaints of pain in the left eye associated with redness for 3 days, nasal block with discharge for 5 days, breathlessness for 10 days, and cough with expectoration for 10 days. He was diagnosed to have fungal rhino sinusitis (mucormycosis), orbital cellulitis (mucormycosis), uncontrolled diabetes mellitus, ischemic heart disease, dilated cardiomyopathy with severe left ventricular systolic dysfunction with severe pulmonary artery hypertension, and nephropathy. He was on treatment with insulin for diabetes, tablet ecospirin for ischemic heart disease, and injection amphotericin for fungal rhino sinusitis. He was proposed for left orbital exenteration surgery. On examination, the patient was drowsy. His pulse rate was 86/min, irregular in rhythm, and blood pressure measured in right arm in supine position was 100/60 mm Hg. There was swelling of left eye with discharge. Cardiovascular system examination showed split in second heart sound. Respiratory system examination showed bilateral extensive rhonchi and rales. Oxygen saturation on room air was 91-92%. Airway examination showed modified Mallampati score of 3. His fasting blood glucose was 409 mg/dl and random glucose level was 329 mg/dl. His hemoglobin was 10.7 gm/dl, blood urea was 92 mg/dl, and serum creatinine was 2.0 mg/dl. Serum sodium level was 133 mEq/L and potassium level was 3.5 mEq/L. ECG showed right bundle branch block pattern and Q wave in leads V1–V3. Echocardiography showed global hypokinesia of left ventricle with left ventricular ejection fraction of 25%, severe pulmonary arterial hypertension, dilated cardiac chambers with apical clot in the right ventricle, and sclerosed aortic valve. Chest radiography showed features of cardiomegaly and congestive cardiac failure. Computed tomography (CT) scan of paranasal sinuses with orbit showed pan sinusitis and left orbital cellulitis with no intracranial extension. Considering the risk factors like congestive cardiac failure, sepsis, inadequate control of blood sugar, renal failure, and ischemic heart disease with poor left ventricular ejection fraction, grave risk consent was taken. All standard monitors like pulse oximetry, non-invasive blood pressure (NIBP) and ECG, were connected. Intravenous access was obtained with 18 G cannula. Oxygen was administered through nasal prongs.\nThe patient was placed in supine position with the head in neutral position and the eyes staring straight ahead. The anatomic landmark was marked at a point 3 cm lateral to the angle of the mouth on the left side. The skin over the cheek on the involved site was prepared with povidone-iodine and draped. A skin wheal was raised with a local anesthetic. A 22G, 10 cm-long spinal needle was inserted here [] and advanced upward toward the mandibular condyle in a plane lining with the patient's pupil as the patient's eyes stared ahead, and the trajectory was cephalad toward the external auditory meatus. At a depth of 5 cm, the greater wing of the sphenoid at the base of the skull was contacted. The needle was withdrawn and redirected more posteriorly to enter the foramen ovale. It was then advanced 1.5 cm. Paresthesia at the mandible was elicited, followed by paresthesia in the maxilla and orbit. Before injecting the local anesthetic, the needle was carefully aspirated to check for cerebrospinal fluid (CSF) and 2 ml of lignocaine 2% with 5 ml of bupivacaine 0.5% was given. Supraorbital and supratrochlear block was given with 0.5% bupivacaine 3 ml each. Intravenous sedation was given with midazolam 1 mg and morphine 3 mg. Patient was monitored all the time during surgery. Oxygen saturation was between 97% and 98%, blood pressure was ranging from 100/60 to 110/60 mm Hg, and heart rate was between 90/min and 106/min. The patient was specifically monitored for signs of an oculo-cardiac reflex. A standard exenteration was performed and the patient tolerated the procedure well with no episodes of hypoxia or bradycardia. The patient was comfortable during surgery. Blood sugar was controlled with insulin 5 U bolus and at an infusion rate of 2U/h. Blood sugar was between 170 and 220 mg/dl. Postoperatively pain was controlled with injection tramadol 50 mg tid.