Bilateral brachial plexus blocks in a patient of hypertrophic obstructive cardiomyopathy with hypertensive crisis
A 50-year-old man, weighing 80 kg, who was 1.58 m tall (body mass index = 32 kg/m2) was admitted to the emergency room with a traumatic amputation of the right upper limb up to about 5 cm distal to the elbow joint and a contused lacerated wound (CLW) extending circumferentially around the left distal forearm. Both the wounds were badly contaminated and the amputated limb was bleeding. He was on Tab. Amlodipine 5 mg once daily for hypertension and, Glipizide 5 mg once daily and Metformin 500 mg twice daily for type-2 diabetes mellitus since 2 years. He was also a known case of HOCM and had undergone alcohol ablation of the interventricular septum one year ago.\nHe was conscious and oriented. His pulse rate was 120/m and the blood pressure (BP) in his left lower limb was 210/120 mmHg (mean arterial pressure (MAP) = 150 mmHg). A systolic murmur was heard over the left parasternal area. The respiratory system examination was normal. The mouth opening was one-and-a-half fingers breadth, he had Mallampati airway class-3 and the upper two incisors were loose and broken. Neck extension was restricted and the thyromental distance was three fingers breadth.\nHis haemoglobin was 11 g/dl, blood sugar was 173 mg/dl, blood urea was 26 mg/dl, serum creatinine was 1.3 mg/dl and serum electrolytes were normal. An electrocardiogram revealed a left bundle branch block with left ventricular hypertrophy []. Echocardiography showed a thickened interventricular septum, systolic anterior motion of the anterior mitral leaflet, left ventricular outflow tract gradient of 60 mmHg, left ventricular ejection fraction of 45%, good right ventricular function and no mitral regurgitation. A chest X-ray showed cardiomegaly with no signs of congestive cardiac failure. The cervical spine X-ray revealed spondylotic changes at C5-C7.\nAn intravenous access was secured on the left foot. The right dorsalis pedis artery was cannulated and continuous BP monitoring was initiated. Intravenous fentanyl 150 μg and labetalol 10 mg, followed by an infusion of 2 mg/min, were administered. After 20 min, his heart rate decreased to 106/min and BP to 196/114 mmHg (MAP 140 mmHg). He was scheduled for emergency hemostasis and debridement of the amputated limb and contused lacerated wound. The patient was nil-by-mouth for 2 h.\nIn the operation theater, after applying the standard monitors, the right subclavian vein was cannulated and central venous pressure (CVP) monitoring was initiated. The initial CVP was 4 mmHg. The BP had decreased to 180/110 mmHg (MAP = 133 mmHg) and pulse rate to 90-100/min. It was decided to achieve the hemostasis and debride the amputated limb first, and follow it up with debridement of the CLW.\nRight brachial plexus block was performed via a supraclavicular approach using a 23 G needle. After eliciting paraesthesia, a mixture of 6 ml 2% lignocaine and 18 ml 0.5% bupivacaine was injected slowly with frequent aspirations. He was sedated with intravenous midazolam 2 mg following initiation of the block. The debridement and revision amputation were completed in 120 min. Following this, left axillary block was performed with a mixture of 8 ml 2% lignocaine and 30 ml 0.25% bupivacaine using a multiple injections technique. Both the blocks worked adequately. Intraoperatively, the pulse rate and MAP were maintained at 80-90/min and 110-120 mmHg, respectively. The total blood loss was 500-550 ml. The blood sugar was monitored hourly, and it was maintained between 100 and 200 mg/dl with insulin infusion. The surgeries were uneventful and the patient was shifted to the intensive care unit. Analgesia lasted for 6 h post-operatively, which was managed further with fentanyl infusion.