Estimated reading time: 7 minutes
Subedited by Dr Phil Tucak
A five-month-old male labrador was referred from another emergency hospital following unsuccessful attempted endoscopic removal of a fishhook from his oesophagus. On the initial endoscopic examination, it was believed that the hook perforated the oesophageal wall. The patient was subdued on presentation, but all other physical examination findings were within normal limits.
Radiographs showed the position of the hook as located approximately between the 5th to 7th ribs, and lying transversely across the cardiac silhouette.. No pleural fluid or gas was identified. Contrast agent Iohexol (Omnipaque) was instilled down the oesophagus to assess for the presence of significant oesophageal wall tear.
There was no contrast visible outside of the oesophagus. Blood gas analysis was performed prior to general anaesthetic, the only significant findings being mild hyperglycaemia, presumedly stress-related, and mild hypercalcaemia (ionised), presumedly age-related. A fentanyl constant rate infusion (2-10ug/kg/hr IV) was commenced, and endoscopic examination performed to confirm the degree to which the hook had perforated the oesophagus and confirm the requirement for exploratory thoracotomy.
Endoscopic examination revealed only the eyelet and approximately one centimetre of the shaft of the hook was visible within the oesophageal lumen, meaning close to two-thirds of the hook was external to the oesophagus. The patient was prepared for thoracotomy and perioperative cephalothin (25mg/kg IV q90 minutes) was commenced.
The patient was placed in right lateral recumbency, intercostal nerve blocks were performed with bupivacaine (2mg/kg evenly distributed over all sites) at the caudal aspect of ribs six to nine, and a lateral approach was made, at intercostal space seven. Mechanical ventilation commenced once the thoracic cavity was breached.
Examination of the major thoracic structures was somewhat hampered by the presence of a mediastinal haematoma. The hook was visible exiting the oesophagus, and the point of the hook was identified to be penetrating into the cranial vena cava. The entire point and barb were embedded within the vena cava.
The shaft of the hook was transected with pin cutters and the eyelet end of the hook allowed to remain within the oesophagus to pass through the gastrointestinal tract, as the risk of further damage was assessed as being lesser than the risk of complications associated with surgically opening the oesophagus. The puncture through the oesophageal wall was closed with a simple cruciate suture of 4-0 PDM.
Prior to attempting to remove the barb from the vena cava, the patient was blood typed as DEA-1.1 negative and whole blood was on hand if required. The barb and point end of the hook was removed from the vena cava and resulted in significant blood loss. Visualisation was particularly hampered by already present haematoma, as well as surgical bleeding.
Attempts to effectively manually occlude the vena cava to allow surgical repair of the wall deficit were unsuccessful. The patient became hypotensive and whole blood transfusion commenced (total of two units of whole blood administered). Topical haemostatic agents were applied (Lyostypt and BleedSolv) with manual pressure, and eventually, the vessel was able to be occluded manually with digital pressure from a surgical assistant to stem bleeding.
The thoracic cavity was suctioned of blood and while the vena cava was occluded, the deficit in the wall was oversewn with simple continuous suture of 4-0 PDM. Tranexamic acid (15mg/kg slow IV) was administered in an attempt to prevent clot lysis. Manual pressure was maintained for 10 minutes, and then slowly released to assess for ongoing haemorrhage. Adequate haemostasis was achieved.
The thoracic cavity was lavaged with warm saline and suctioned, then reassessed for any ongoing haemorrhage; none was found. A chest drain (14Ga Mila chest drain) was placed via the Seldinger method and the thoracic cavity was closed routinely. Negative pressure was obtained via evacuation of the pleural space through the chest drain. Mechanical ventilation was continued until the patient commenced spontaneous ventilation maintaining adequate oxygenation parameters.
Post-operatively coagulation profile was within normal limits, haematocrit was 34%, total solids 44g/L, blood gas analysis showed a respiratory acidaemia with hyperglycaemia and hyperlactataemia. An oesophageal tube was placed to ensure the ability to maintain adequate protein intake while bypassing the surgical site and minimising leakage from the trauma site.
Due to periods of hypotension during surgery, a biochemistry profile was performed postoperatively and monitored in hospital over the following days. Respiratory acidaemia resolved over the hours following anaesthetic recovery. Antibiotics (cephalothin), analgesia, antiemetics, parenteral nutrition and fluid support were continued post-operatively and the patient was discharged three days after presentation without requiring further transfusions, or experiencing any significant complications.
Our team examined the case in mortality and morbidity rounds following discharge, and identified multiple areas of potential improvement if faced with a similar case. Ideally, a computed tomography scan would be performed prior to surgery to identify the structures involved and would have allowed for complete pre-surgical planning. This facility was not available to us at the time.
With the surgical approach to the cranial vena cava, pre-placement of sutures and an alternate approach to occlusion of the vena cava may have resulted in less intra-operative haemorrhage. Dissection around the vessel, and placement of a Rumel tourniquet may have resulted in improved visualisation and haemostasis when removing the hook.
Preplacement of suture within the wall of the vena cava, prior to incision and removal of the hook, may have allowed the surgeons to close the vessel more rapidly, as well as enabling improved suture placement as not compromised by haemorrhage reducing visibility.
One study of 125 cases of oesophageal perforation secondary to foreign bodies found that fishhooks were the second most common foreign body identified (bones were the first) and were associated with a 27% incidence of perforation (Sterman et al., 2018).
Our hospital routinely manages fishhook injuries, including cutaneous injuries as well as ingestions. The majority of our oesophageal and gastric foreign bodies are managed via successful endoscopic retrieval, and fishhooks are the single most frequent of these. However, this is the first case the authors have had of an oesophageal perforation resulting in major vessel trauma.
Dr Danielle Huston BVSc (Hons) MVS (Small Animal Practice) MANZCVS (Emergency and Critical Care) Animal Emergency Service Tanawha
Dr Danielle Huston graduated from the University of Queensland in 2010. She was already working for Animal Emergency Service as a vet nurse while at university, and stayed on as a new graduate veterinarian.
Dr Huston worked in Brisbane until transferring to the Sunshine Coast Animal Emergency Service in 2014. Since then, she has gained her Masters in Small Animal Clinical Practice from Murdoch University (2017) and obtained her Membership in Emergency and Critical Care from the Australian and New Zealand College of Veterinary Scientists.
Dr Huston went from associate veterinarian to veterinary manager to now hospital director.
Dr Harrison Mackenzie BVMSci (Hons) FCert (ECC) MRCVS Animal Emergency Service Tanawha
Dr Harrison Mackenzie graduated from the University of Surrey, in the UK, in 2020 with an interest in small animals. He spent two years in a RCVS Tier 3 hospital with general practice and referral services.
After developing an interest in surgery and ECC, Dr Mackenzie moved to AES Tanawha to develop his skills in the emergency field completing the Improve International Accelerated Program to obtain a Foundation Certificate in Emergency and Critical Care.
Since then, he has taken on the role of managing the blood bank and aims to pursue further study in the field of surgery, with a view to using these skills in an emergency and critical care context.
