Anesthetic challenges in the simultaneous management of pulmonary and hepatic hydatid cyst.

Hydatidosis is a parasitic infection caused by the encysted larvae of Echinococcus granulosus, commonly called as hydatid cyst. Almost all organs can be involved, but most commonly it affects liver (55%-70%) followed by the lungs (18%-35%). The surgery and anesthetic management become very challenging if these cysts are in or near the vicinity of vital organs, such as heart. Pulmonary hydatid cysts may rupture into the bronchial tree or pleural cavity and produce cough, chest pain, or hemoptysis and there are chances of injury to heart if the cyst is in close proximity to it. We are describing the successful management of such a case of pulmonary and hepatic hydatid cyst in a young female patient.

INTRODUCTION

Hydatidosis is a parasitic infection caused by the encysted larvae of Echinococcus granulosus, commonly called as hydatid cyst. Almost all organs can be involved, but most commonly it affects liver (55%–70%) followed by lungs (18%–35%). Thoracic complications of hepatic hydatid cyst are seen in approximately 0.6%–16% cases.[12] The surgery and anesthetic management becomes very challenging if these cysts are in or near the vicinity of vital organs, such as heart. We are reporting a case of pulmonary and hepatic hydatid cyst that was operated endoscopically and successfully managed from anesthesia perspective as the thoracic cyst was in close proximity with the cardiac tissue.

CASE REPORT

A 45-year-old woman from a semiurban area came to the surgery outpatient department of our hospital with a history of intermittent pain abdomen since 3 months, loss of appetite since 1 week and sudden onset of mild breathlessness since 3 days. There was no history of jaundice, hematemesis, malena, nausea and vomiting, chest pain, or any systemic medical disease. History of previous exposure to general anesthesia for fixation of fracture humerus was uneventful but was associated with delayed emergence from anesthesia as per the history elicited from the patient but the detailed documents were not available.

During preanesthetic evaluation, her heart rate was found to be 86/min with occasional missed beats; blood pressure was 118/72 mmHg and on auscultation of chest there was decreased air entry over left lower zones. Cardiovascular examinations, including echocardiography were normal except for electrocardiogram (ECG), which revealed a few abnormal ventricular complexes (<5–6/min). On palpation of abdomen, tenderness was present over left hypochondrium and epigastric region but with no associated organomegalies. Airway examination revealed normal parameters with Mallampatti Score grade II. Chest X-ray (postero-anterior view) revealed a cystic lesion with air and fluid level at left lower zones [Figure 1]. Contrast-enhanced computed tomography showed a 6.1×5.4×5.0 cm well-defined cystic lesion in segment III, VI, and Va of hepatic tissue [Figure 2]. Immunohemagglutination test for echinococcosis was found to be positive. The patient was diagnosed as a case of hydatid cyst of liver and lower lobe of left lung and the cyst was in close proximity to the heart [Figure 3]. Thoracoscopic drainage/excision of lung cyst and laparoscopic drainage/excision of liver cyst was planned as the surgical intervention. Tab albendazole 400 mg twice daily was started 2 weeks prior to surgery. All routine investigations, including hemogram, renal function tests, hepatic function tests, blood glucose, viral markers, and urine routine examination were within the normal limit except for mild increase in serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic-pyruvic transaminase (SGPT) levels. The patient was taught about the merits of incentive spirometry and was instructed to practice it regularly both pre- and post-operatively.

Figure 1

Wholebody scanned image showing the hydatid cyst in the left lung and liver

Figure 2

Scanned image showing the hepatic location of the hydatid cyst

Figure 3

Scanned image showing the pulmonary hydatid cyst in the left lower lung in proximity to the heart

Before the surgical operation, written informed consent from the patient was taken after explaining to her the various surgical and anesthetic implications of the procedure. Preoperatively, tab. ranitidine 150 mg, tab. metoclopramide, and tab. alprazolam 0.25 mg were administered a night before and on the morning of surgery as premedication. General anesthesia and double lumen tube intubation was planned for isolation of lungs during surgical procedure.Thoracic epidural analgesia was also planned for intra- and postoperative pain relief and possibly to decrease the anesthetic dose requirement during the surgery.

After shifting the patient to operation theater, monitors were attached for ECG, noninvasive blood pressure (NIBP), end-tidal carbon dioxide (ETCO2), and pulse oximetry (SpO2). Intravenous access (IV) was secured with two large bore cannulae in both the upper limbs. Inj. hydrocortisone 100 mg IV and Inj. chlorpheniramine 25 mg IV were injected before induction of anesthesia in anticipation of anaphylaxis to possible spillage of contents of the cysts during surgery. Inj. adrenaline and Inj. theophylline were kept ready for the same purpose. Under all aseptic conditions, epidural catheter was inserted at T9–T10 space and fixed at 5 cm into the epidural space. After negative aspiration for blood and cerebrospinal fluid, 3 mL of 2% lignocaine with 15 μg adrenaline was injected as test dose. Five minutes after the test dose, 8 mL of 0.75% ropivacaine was injected into epidural space. As part of pretreatment before induction of anesthesia, Inj. midazolam 1 mg IV, Inj. glycopyrollate 0.2 mg IV and Inj. fentanyl 50 μg IV were administered. Induction of anesthesia was carried out with Inj. thiopentone sodium 250 mg, and complete muscle relaxation was achieved with Inj. suxamethonium 100 mg and then trachea was intubated with 35 Fr left-sided double lumen tube (Bronchocath). Bilateral equal air entry was checked and confirmed while ventilation for each lung was checked individually after blocking bronchial and tracheal lumen alternatively. Finally, the position of double lumen tube (DLT) was checked and confirmed by fiberoptic bronchoscopy. Anesthesia was maintained with O2, N2O, and isoflurane. Muscle relaxation was maintained with Inj. vecuronium bromide as and when required. We avoided administration of atracurium in lieu of its potential to release histamine and a possible accentuation of anaphylactic reaction.

Thoracoscopy was done in right lateral decubitus position after clamping bronchial lumen and ventilating only the right lung. After every 30 min, surgical procedure was stopped and both lungs were ventilated for 5 min. After about 40 min of initiation of surgery, during thoracoscopic handling of lung cyst, bradyarrhythmias were observed on ECG monitor that subsided spontaneously when surgeon was asked to stop surgery at that moment. Two similar episodes of arrhythmias occurred again on initiation of surgery, which subsided spontaneously again on stoppage of surgery. But when it occurred for the fourth time, Inj. lignocaine 60 mg was given stat IV to terminate it. After about another 5 min, the abnormal ventricular complexes appeared again for which Inj. amidarone 150 mg was administered as bolus and followed by its infusion. Thereafter, the surgical procedure was accomplished uneventfully. After drainage and excision of lung cyst, the patient was made supine and laparoscopic drainage and excision of liver cyst was carried out. During this phase of surgery, ventilation of both the lungs was carried out simultaneously. Throughout surgery, continuous monitoring of HR, ECG, NIBP, SPO2, and ETCO2 was done. Intermittently, ABG was also done to know about the metabolic profile and oxygenation status. All the parameters, including fluid intake and urine output remained within normal limits throughout the surgical procedure. At the end of surgery, residual neuromuscular blockade was reversed with Inj. neostigmine 2.5 mg and Inj. glycopyrrolate 0.05 mg. Trachea was extubated when the patient became fully conscious and started obeying verbal commands. Thereafter, the patient was shifted to intensive care unit (ICU) for further observation and management. In the ICU, pain relief was managed by epidural top-up of 8 mL of 0.25% ropivacaine as and when required. Postoperative ECG and echocardiography were carried out, which were within the normal limit. Overall, the recovery was uneventful and the patient was shifted to the surgical ICU next day.

DISCUSSION

Hydatid disease or Echinococcosis is an infection of humans caused by the larval stage of Echinococcus granulosus, Echinococcus multilocularis, or Echinococcus vogeli E. granulosus, which produces unilocular cysts, is prevalent in areas where livestock is raised in association with dogs. The definitive hosts are dogs that pass eggs in their faeces. Human infestation occurs after ingestion of the eggs as embryos escape from the eggs, penetrate the intestinal mucosa, enter the portal circulation and are carried to various organs, most commonly to the liver and the lungs. The echinococcal cyst expands slowly over a period of time but usually remain asymptomatic until their expanding size elicits symptoms due to the mass effect. Hepatic hydatid cyst manifests as abdominal pain or a palpable mass in the right upper quadrant. Rupture of a hydatid cyst may produce fever, pruritis, urticaria, eosinophilia, or anaphylaxis. Pulmonary hydatid cysts may rupture into the bronchial tree or pleural cavity and produce cough, chest pain, or hemoptysis.[3] Traditionally, surgery has been the mainstay method of treatment but the risks involved during surgery includes dissemination of infectious scolices from leakage of fluid as well as anaphylaxis. Medical management for this disease entity include oral albendazole alone for 12 weeks to 6 months and the success rate of this method is approximately 30%.[3]

Anesthetic implications of a case of hydatid cyst of the lungs is a challenge for anesthesiologist, which include the problems associated with one lung ventilation (OLV) and rupture of the cyst and dissemination. Bronchi opening into the pericyst cavity also allows for discharge of hydatid liquid directly into its lumen. Even operative manipulations can also force fragments of laminated membrane or small daughter cysts into the bronchial tree. These extruded solid fragments lodge in bronchi of the same or opposite lung, resulting in acute obstruction of the airways. Inadvertent spillage of cyst contents may cause secondary pleural or bronchogenic hydatidosis. Such complications can be avoided by isolation of lungs by OLV technique. Intentional collapse of the lung on the operative side facilitates most of the thoracic procedures but performing these maneuvers can make it all the more challenging. The most frequent complication during OLV is due to ventilation-perfusion mismatch, resulting from the combination of position, OLV, and lung disease. Moreover, malpositioning of DLT results in failure to collapse the operative lung; difficulty in ventilating one or both the lungs; and air trapping and unsatisfactory deflation of the lung. Confirmation by fiberoptic bronchoscopy can significantly reduce such malpositioning. Our problem became multidimensional as the patient had arrhythmias during surgery. Tracheobronchial trauma and hemorrhage are the other associated complications associated with DLT.[4]

A hydatid cyst of lung warrants double-lumen tube intubation of the trachea during surgery not only to control ventilation but also to prevent flooding of the contralateral healthy lung[56] and double-lumen tube intubation should also be considered in some hydatid cysts of the liver with concomitant thoracic involvement.[79]

The magnitude of allergic reactions ranges from mild hypersensitivity to fatal anaphylactic shock.[8-10] Anesthetic implications in our case included high chances of hemodynamic instability due to the close proximity of the cyst to heart, difficulty in ventilation due to atelectasis of left lower lung, and surgery over the anatomical site possibly causing rupture of cysts and leading to anaphylaxis. In our patient, there was a history of delayed emergence from previous exposure to anesthesia; so we avoided the drugs that are likely to produce respiratory depression and anesthesia was supplemented with intermittent epidural top-up. The episodes of ventricular arrhythmias during surgery could possibly be explained on the basis of close proximity of the pulmonary surgical site to the heart, which could have resulted in the direct stimulation of cardiac tissue.

To conclude that management of a case of hydatid disease of the lungs and liver for endoscopic surgery include thorough understanding of the respiratory physiology of the OLV and the proper positioning of the double-lumen endobronchial tube and continuous monitoring of the saturation, ventilation, and the blood gases to prevent any associated complications.