Cardiomediastinal tamponade and shock following three-stage transthoracic oesophagectomy.V Cherian, JV Divatia, A Kulkarni, D Dasgupta
Department of Anaesthesia, Critical Care and Pain, Tata Memorial Hospital, Parel, Mumbai - 400 012, India., India
Correspondence Address: Source of Support: None, Conflict of Interest: None PMID: 11832620
Source of Support: None, Conflict of Interest: None
Massive gastric tube dilatation causing cardiomediastinal tamponade is an unusual cause of obstructive shock after transthoracic oesophagectomy. A 55-year-old female was operated for total transthoracic oesophagectomy. Twelve hours after the surgery, she developed hypotension and raised central venous pressure unresponsive to fluid infusion and ionotropes. X-ray chest showed a massively dilated stomach, which was causing intrathoracic tamponade. Suction applied to the nasogastric tube led to aspiration of 150-200 ml of fluid and a large volume of air, which led to resolution of the haemodynamic instability. A simple manoeuvre like nasogastric suction in postoperative case of oesophagectomy can serve as a diagnostic as well as therapeutic tool. It must be performed before resorting to invasive and expensive examination or intervention.
Keywords: Blood Pressure, Carcinoma, Squamous Cell, surgery,Cardiac Tamponade, diagnosis,etiology,Case Report, Diagnosis, Differential, Esophageal Neoplasms, surgery,Esophagectomy, Female, Human, Hypotension, etiology,Middle Age, Postoperative Complications, Suction,
Transthoracic total oesophagectomy is a surgical technique for carcinoma of middle third of oesophagus. The oesophagus is mobilised by a right thoracotomy approach and a laparotomy is performed to create the stomach tube, which is anastomosed to the oesophageal remnant in the neck. Several intraoperative and postoperative complications have been reported, including arrhythmia and anastomotic dehiscence causing mediastinitis and septic shock. A case with postoperative obstructive shock of an unusual aetiology is reported here.
A 55-year-old female patient with squamous cell carcinoma of oesophagus was scheduled for a transthoracic total oesophagectomy. The patient had a history of hypertension and was treated with enalapril. She had no other significant medical problems. Her biochemical and haematological values, ECG and pulmonary functions tests revealed no significant abnormality.
The patient received enalapril on the morning of surgery and diazepam 30 minutes before surgery. Her blood pressure was 140/80 mm of Hg and pulse rate 94/min. Anaesthesia was induced with thiopentone sodium and suxamethonium chloride was given and the trachea was intubated with a cuffed endotracheal tube. Anaesthesia was maintained with buprenorphine, nitrous oxide, oxygen and isoflurane. Pancuronium was used to facilitate intermittent positive pressure ventilation. Prior to completion of the oesophago-gastric anastomosis, a 14G nasogastric tube was positioned in the stomach. Surgery lasted for six hours.
Postoperatively she was ventilated electively. She was haemodynamically stable, her haemogram, renal and liver function tests were within normal limits. The chest X- ray showed well-expanded lungs, without pleural air or fluid collections. The nasogastric tube was seen within a slightly dilated stomach tube in the right hemithorax. The nasogastric tube was placed on continuous gravity assisted drainage.
On the next postoperative day the nasogastric tube aspirate was 15 ml. She was maintaining satisfactory arterial blood gas values on spontaneous ventilation with a pressure support of 15 cm H2O, CPAP 5 cm H2O, and FiO2 of 0.4. However she became tachypnoeic during a T-piece spontaneous ventilation trial and mechanical ventilation was continued.
Her blood pressure was 120/70 mm of Hg, pulse rate 80/ min; however the central venous pressure (CVP) was 15-16 cm of H2O. Over the next half an hour, she developed hypotension with a systolic blood pressure of 80 mm of Hg and a pulse rate of 120/min. The CVP rose to 16-17 cm H2O. All the peripheral pulses were felt very feebly. Percussion of the chest revealed a hyperresonant note over the right hemithorax. Breath sounds were heard clearly on both sides of the chest. Tracheal shift was not evident. The heart sounds were well heard in the mitral area, without murmur, gallop or a pericardial rub. The central venous catheter was connected to a pressure transducer and direct continuous monitoring was commenced. Femoral artery cannulation was attempted. A chest X-ray was performed and a transthoracic echocardiogram was requisitioned, but was not immediately available. 500 ml of polygeline was given rapidly. The CVP rose to 20 mm of Hg. A dopamine infusion was instituted at 8 mcg/kg/min, without any improvement in blood pressure.
On auscultation over the right midaxillary line, a loud tinkling sound with a prominent succusion splash was heard. Continuous suction was attached to the nasogastric tube. Deflation of the stomach tube was accompanied by an improvement in the haemodynamic status of the patient. The systolic blood pressure rose to 110 mm of Hg as the CVP fell to 10-12 mm of Hg. About 150 - 200 ml of fluid and a large immeasurable volume of air were aspirated.
The chest X-ray revealed a hyperluscency with absence of lung markings in the right hemithorax, with a shift of mediastinum to the left, suggestive of a right-sided pneumothorax. However the nasogastric tube could be seen along the lateral edge of the hyperluscent area confirming the diagnosis of a dilated stomach tube [Figure - 1]. Following deflation of the stomach contents, the nasogastric tube was placed on continuous suction. The patient remained haemodynamically stable. A subsequent chest X- ray showed well-expanded lungs with a central mediastinum, and stomach tube in its usual position.
She was ventilated for another 24 hours and extubated the next day. The patient was haemodynamically stable during her course in the ICU. She was discharged from the ICU on the eighth postoperative day.
In our patient, hypotension occurred on the first post-operative day. The presentation was that of shock associated with high cardiac filling pressures. Infusion of colloids and dopamine resulted in further increase in the CVP with no improvement in the blood pressure. The differential diagnosis included tension pneumothorax, cardiac tamponade due to pericardial effusion, acute congestive cardiac failure or pulmonary embolism.
Pneumothorax is a common occurrence after oesophageal surgery. The presence of a hyperresonant percussion note over the right hemithorax did suggest the possibility of a right pneumothorax. However breath sounds were clearly heard, and there was no tracheal shift at the first assessment. The absence of muffling of heart sounds did not support the possibility of a pericardial effusion. However an echocardiogram was requisitioned because it was important to definitively exclude the diagnosis of cardiac tamponade.
The high CVP and low blood pressure also could have been due to cardiac failure. Our patient had a history of hypertension, and myocardial ischemia has been reported after retrosternal reconstruction of the oesophagus. ST-T electrocardiographic changes, due to an increase in the air space between the heart and the sternum, were reported after retrosternal reconstructive surgery for oesophageal cancer. These changes disappeared after expulsion of a large amount of air that had been retained in the reconstructed oesophagus posterior to the sternum. However in our case the reconstruction was in the posterior mediastinum. In our patient there was no gallop rhythm, and no clinical evidence of left ventricular failure. At this stage, the ECG had not been obtained because priority was given to the chest X-ray, in order to confirm or exclude the diagnosis of pneumothorax, and give some clue regarding the presence of a pericardial effusion and pulmonary congestion. Pulmonary embolism could also present in a similar fashion.
Further clinical evaluation of the patient revealed a succusion splash over the right hemithorax, which led us to believe that a hydropneumothorax or a massively dilated stomach tube was present with air and fluid within it. Aspiration of the nasogastric tube resulted in large volume of air and fluid being drained with resultant improvement in the haemodynamics. The chest X-ray, which had been taken earlier, showed a hyperluscency in the right hemithorax. This could have been misread as a large pneumothorax. However close inspection revealed the presence of the nasogastric tube along the lateral edge of the hyperluscency. This confirmed the diagnosis of a massively dilated stomach tube in the right hemithorax, which had presented with haemodynamic instability.
There has been a case report of obstructive shock due to labour related diaphragmatic hernia, where the initial signs and symptoms were similar to those seen in our case. The herniated loops of bowel led to mediastinal shift leading to hypotension and elevated central venous pressure. A similar presentation has been described during gastrointestinal endoscopy. The stomach had herniated through a diaphragmatic hernia into the left hemithorax. Insufflation of the stomach during endoscopy resulted in cardiovascular collapse due to cardiomediastinal tamponade by the gas-filled stomach.
Thus cardiomediastinal tamponade is an uncommon but readily treatable cause of obstructive shock. It can be diagnosed by simple clinical examination, and easily treated by nasogastric aspiration. This manoeuvre should be performed before any further diagnostic tests or invasive monitoring is undertaken.
[Figure - 1]