Successful management of spontaneous pneumothorax during general anaesthesia in a patient with eosinophilia.KA Shah, A Shetty, LS Chaudhari
Department of Anaesthesia, Seth G. S. Medical College, Mumbai.
A 10-year-old male patient posted for left elbow arthrolysis developed pneumothorax during general anaesthesia. He had history of upper respiratory tract infection and high eosinophil count, which remained high in spite of treatment. In such patients, it is advisable to use steroid pre-operatively & intraoperatively to produce transient eosinopenia so that complications of eosinophilia are avoided.
Keywords: Anesthesia, General, adverse effects,methods,Case Report, Child, Eosinophilia, complications,drug therapy,Human, Hydrocortisone, therapeutic use,Male, Pneumothorax, etiology,prevention &control,therapy,
Many patients with eosinophilia are encountered in anaesthesia practice. Despite treatment, many patients show high eosinophil count and are taken up for anaesthesia.
Eosinophils can cause release of mediators, which can cause bronchoconstriction.
During anaesthesia with positive pressure ventilation, when associated with bronchospasm, can precipitate into pneumothorax, especially when positive pressure is high.
A 10-year-old male patient, weighing 25kg, ASA grade II risk was posted for left elbow arthrolysis. Patient had history of mild upper respiratory tract infections. Physical examination revealed pulse rate of 98 per minute, regular rhythm, blood pressure of 110/80 mm of Hg and respiratory rate of 18 per minute. On auscultation, chest was clear and without any foreign sounds. Laboratory examination showed total leucocyte count of 10,000/cu.mm with mild eosinophilia (14%). The absolute eosinophil count was of 1400.The X-ray chest was within normal limits. It was decided to treat eosinophilia with tablet Mebendazole for three days and tablet Diethylcarbamazine for 21days before taking up the patient for surgery.
After treatment, repeat total leucocyte count again, was of 10,000/cu.mm with mild eosinophilia (12%). The absolute eosinophil count was of 1200. As the patient was asymptomatic and clinically chest was clear, it was decided to take him up for surgery.
Glycopyrrolate was injected as a pre-medication. On table, cardioscope and pulse oximeter probes were connected to the patient. Pre-operative pulse rate was 108 per minute and pulse oximeter showed oxygen saturation of 98%. Diazepam (2mg) and Pentazocine (12mg) were given intravenously. The patient was induced with 2.5% Thiopentone sodium (l00mg) and intubation was facilitated with intravenous succinylcholine (50mg). He was intubated with well lubricated 5.5mm cuffed Rusch endotracheal tube after spraying the cords with 4% Xylocaine. Air entry was bilaterally equal. Anaesthesia was maintained with N2O:O2 (60:40) and non depolarising muscle relaxant pancuronium.
Surgery commenced in right lateral position. Intraoperatively patient maintained pulse rate between 100-120 per minute, blood pressure between 120-130 mm of Hg systolic and saturation between 98-100%. After one and half hour of induction there was sudden fall in oxygen saturation from 100% to 90% and to 50% in another few seconds, associated with resistance to ventilation. However, pulse rate and blood pressure were maintained. N2O was switched off and patient was ventilated with 100% oxygen. On auscultation of chest there was decreased air entry on right side. Position of endotracheal tube was rechecked and endotracheal suction was done to rule out blockage of tube. After all these measures saturation improved to 80%, however resistance to ventilation persisted. Since patient was haemodynamically stable, surgery was continued with patient maintains on oxygen, halothane (0.5-1.0%) and pancuronium. After completion of surgery, patient was made supine and x-ray chest was taken which revealed pneumothorax on right side. After intercostal drain, air entry improved remarkably and saturation improved to 98%. Neuromuscular blockade was reversed with intravenous atropine (0.6mg) and neostigmine (1.25mg). Patient was extubated after all vital parameters including oxygen saturation were maintained for half an hour. He was shifted to intensive care ward with oxygen mask for observation. He maintained oxygen saturation between 97-99%. No untoward events occurred after this. Intercostal drain was removed on third post-operative day after confirming that x-ray chest revealed normal lung expansion. He was discharged on the seventh postoperative day.
Eosinophils are produced by bone marrow and are chiefly present in the blood before they enter the tissues. In the peripheral blood they remain for an average of 13-18 hours in normal patients and longer in some disease states.2 Normal blood generally contains between 50-250 eosinophils/ul. In this regards absolute blood eosinophil count is preferred to blood eosinophil percentage.
Eosinophils cause release of mediators, cationic proteins and eosinophilic cationic proteins from mast cells and basophils. This facilitates the entry of inflammatory mediators to afferent nerve endings, leading to bronchoconstriction through axon reflex pathways.
Severe airway obstruction may cause pneumothorax when airtrapping has caused overpressurisation of alveoli.
Eosinophilic lung disease or Loeffler's syndrome has peripheral eosinophils with transient migratory pulmonary shadows. Some are asymptomatic but some have cough with yellowish sputum. It is most often parasitic and treatment is that of causative agent.
Eosinophilia seen in tropics with dry cough especially at night has the aetiology as microfilaria, most often Wucheria bancrofti and treatment is with diethylcarbamazine.
Many parasites can cause pulmonary infiltrates with blood and/or pulmonary eosinophilia, Ascaris lumbricoides, round worm is the most common Although pulmonary symptoms resolve spontaneously over seven to ten days, it should be treated with oral mebendazole l00mg b.i.d. for 3days especially for the intestinal infection.
The predominant features of pneumothorax are tachycardia, hypotension, hypoxemia, unequal air entry, bronchospasm, surgical emphysema and mediastinal shift. The degree of functional derangement with pneumothorax depends upon the degree of collapse. In normal individuals pneumothorax involving 50% of collapse may be well tolerated.
Mechanical ventilation is associated with 3.5% incidence of pneumothorax, which varies with the underlying lung disease, endobronchial intubation or eosinophilia leading to bronchospasm. Erroneous intubation of right main stem bronchus for mechanical ventilation carries high-risk pf pneumothorax.
Corticosteroids remain the mainstay of treatment for Eosinophilia. The mechanism is complex. It leads to rapid, reversible sequestration of eosinophils be bone marrow. Eosinophil adherence as well as chemotaxis can also be inhibited by steroids. It also reduces eosinophil survival by inhibiting cytokines.
Post-operatively this case was discussed with the chest physician from our institute. His advice was that such patients can be taken up for anaesthesia under steroid cover. Intravenous hydrocortisone 2mg/kg tid should be given previous day of surgery and on the morning of surgery.
Patients who have significant eosinophil count inspite of treatment should be administered steroids prior to surgery to prevent life threatening complications like bronchospasm leading to pneumothorax.