Massive hemothorax: A rare complication after supraclavicular brachial plexus block.

Plexus block is the preferred anesthesia plan for upper limb surgeries. Among the known complications, hematoma formation following the vascular trauma is often occur but this complication is frequently underreported. We present a case where a massive hemothorax developed post operatively in a patient who underwent resection of giant cell tumor of the right hand radius bone followed by arthroplasty under brachial plexus block using supraclavicular approach. This case report attempts to highlight the essence of remaining vigilant postoperatively for first initial days after brachial plexus block, especially after failed or multiple attempts. Ultrasound guided technique in combination with nerve stimulator has proven to be more reliable and safer than traditional techniques.

INTRODUCTION

Pneumothorax is the most common complication of brachial plexus block using supraclavicular approach. Other less frequent complications of this technique are injury to nerves, phrenic nerve block, Horner's syndrome etc.[12] Although hematoma formation is a known complication after this block but delayed massive hemothorax is a rare complication. Massive hemothorax is commonly caused by a penetrating trauma and less frequently in central venous cannulation, especially in those with coagulopathy.[34] Recent advances in techniques like ultrasonography with or without a nerve stimulator has significantly reduced the overall complications of these regional blocks. Strict vigilance in the postoperative phase over several hours is the key to minimize morbidity and mortality.

CASE REPORT

A 35-year-old female, weighing 56 kg scheduled for resection of giant cell tumor of the right hand radius bone and later to be followed by arthroplasty. All preoperative routine investigations including coagulation profile were within the normal limits. All standard monitors were attached and patient was monitored for heart rate (HR), electrocardiography (ECG), noninvasive blood pressure (BP) and pulse oximetry (SpO2). Peripheral intravenous (IV) access was secured with 18G cannula. After proper positioning of arm, under all aseptic precautions right supraclavicular brachial plexus block was performed with paresthesia technique using anatomical landmarks. However, it was only in the third attempt that paresthesia could be elicited. Combination of both 0.5% bupivacaine and 2% lignocaine with adrenaline (1:200,000 concentration) was used as per recommended dosages. At the end of the procedure, patient complained of slight chest pain in ipsilateral infraclavicular region. On examination, chest expansion and air entry was bilaterally equal. X-ray chest performed showed no pneumothorax or fluid collection. Patient was sedated with 1 mg of injection midazolam. Patient finally got settled and surgery was allowed to commence after achieving adequate sensory and motor blockade. Her vitals remain stable throughout the procedure. Surgery lasted about one and half hours and was largely uneventful; patient was shifted to the recovery room. In the recovery room patient remained symptom free except for slight chest discomfort at the same site stated above. Evan at that point of time, her vitals were stable (HR - 94/min and regular, respiratory rate [RR] - 16 breaths/min, BP - 119/68 mmHg, SpO2 -99%). On examination, her chest expansion and air entry was still bilaterally equal. ECG showed normal sinus rhythm. Repeat supine X-ray chest was again insignificant. Patient was supplemented with oxygen and adequate sedation and analgesia was ensured. Later on, she was shifted from postanesthesia care unit to her ward. Patient remained symptom free for another 12–14 h. After that, she started complaining chest pain and palpitation of increasing severity. On examination, there was a significant reduction in chest expansion on the right side. On auscultation, air entry was almost absent on the right side except a little portion of right upper lobe. X-ray chest was immediately ordered, which showed a massive fluid collection on the right side with partial collapse of the right lung [Figure 1]. Patient was immediately shifted to operation theater. Her vitals were: HR - 119/min, RR - 30/min, BP - 94/56 mmHg, SpO2 -96%. After adequate oxygenation and aggressive fluid resuscitation with large-bore IV access, intercostal tube drainage was inserted in right fifth intercostal space anterior to midaxillary line. Approximately, 1300 ml of collected blood was drained out. Blood samples were immediately sent for cross matching and emergency investigations (complete blood count with platelets, serum electrolytes and coagulation profiles). Arterial gas analysis showed a mixed picture, that is, compensated metabolic acidosis with respiratory alkalosis. After the evacuation of hemothorax, patient symptoms improved significantly. She was administered 4 units of fresh whole blood. She was immediately shifted to intensive care unit (ICU) and nursed in propped up position. Oxygen, analgesic, and antibiotics cover was also given. Patient finally settled with stable vitals after her stay of 5 days in ICU. Her X-ray chest reveled almost complete expansion of the right lung except for a small portion of the lower lobe [Figure 2]. As this retained part of hemothorax should be cleared early (before fibrosis or infection sets up), patient was sent for computed tomography (CT) guided thoracoscopic evacuation. Later on patient was discharged on tenth postoperative day in satisfactory condition.

Figure 1

Left sided massive pleural collection

Figure 2

Resolving hemothorax with intercostal drain in situ (indicated with white arrows)

DISCUSSION

Massive hemothorax is defined as a collection of more than 1000 ml of blood in the pleural space. Although some text[1] do mention hemothorax as one of the complications, but despite searching major databases including Medline, Embase, Cochrane etc., We could not found case reports of massive hemothorax after this block except, a case reported by Mani et al. that too was attributed to heparin therapy following surgical repair done under brachial plexus block.[2] Most reported hemothoraces are the result of rib fractures, lung parenchymal, spontaneous hemothorax following pneumothorax. Delayed pneumothorax formation after this block has been reported.[3] Small to moderate hemothorax is not detectable by physical examination and can be detected only radiographically. In our patient, rate of blood accumulation in the pleural cavity was quite low and it took around 24 h to become clinically significant. A major vessel might have been injured during the procedure of plexus block to form such a big hemothorax. A self-limited subclavian artery bleed could be the reason as chances of a pleural vessel puncture forming such a massive collection are less. Case reports of such massive hemothorax following central venous catheterization involving subclavian artery damage have been reported.[4] The classic signs of a hemothorax are decreased chest expansion, dullness to percussion and reduced breath sounds in the affected hemithorax. There is no mediastinal or tracheal deviation unless there is a massive hemothorax. Initially these clinical signs may be subtle or absent in the supine patient as it happened with our case. In radiographical signs for hemothorax, Gavelli et al.[5] have reported that in upright position hemorrhage presents as opaque meniscus that dull the costopherinic and cardiophrenic angles. In their study Tocino and Miller[6] found that in supine position as blood collect posteriorly; the only radiological sign may be increased density of the hemothorax with persistent visualization of parenchymal markers. While Lomoschitz et al.[7] reported that in both upright and supine, hemorrhage collects laterally along the wall and at the apex of lung (apical cap sign). Ma and Mateer[8] suggested bedside sonography for evaluation of extent, composition and possible guide for paracentasis. Rivas et al.[9] found CT superior to radiography in such cases. In ECG nonspecific S-T and T-wave changes are often present. Kong and Wood[10] proposed vagal compression can cause profound bradycardia after hemothorax. In our patient, sinus tachycardia was the only ECG finding that too appeared in late stages. Multiple attempts for eliciting paresthesia increases the risk of such complication as it happened in our case. Masoud et al.[11] reported that rate of hematoma formation was directly related to the number of needle punctures and it was 14 times more common in multiple puncture than in single puncture. Most of hemothorax resolve after proper intercostal tube drainage and thoracotomy. Failure to adequately drain a hemothorax can results in residual and clotted hemothorax, which will not drain via a chest tube. If left untreated can lead to empyema formation. Velmahos and Demetriades[12] suggested early thoracoscopy should be done following injury to remove the retained clot. Hence, it is advisable that whenever pleural puncture is suspected, one should not rely only on X-ray chest that too in supine position. Portal ultrasound should be used to guide needle placement for nerve block and it may also be a useful adjunct in diagnosing even a small intrapleural collection.[13] Serial chest X-ray for first few days may be done, especially in the upright position if there is any suspicion of pleural breach. As an alternative to classic approach, “lateral” approach as advised by some workers can be used to decrease overall complications.[14] Continuous vigilance in the postoperative phase is the best strategy.