Building artificial intelligence and machine learning models : a primer for emergency physicians.

There has been a rise in the number of studies relating to the role of artificial intelligence (AI) in healthcare. Its potential in Emergency Medicine (EM) has been explored in recent years with operational, predictive, diagnostic and prognostic emergency department (ED) implementations being developed. For EM researchers building models de novo, collaborative working with data scientists is invaluable throughout the process. Synergism and understanding between domain (EM) and data experts increases the likelihood of realising a successful real-world model. Our linked manuscript provided a conceptual framework (including a glossary of AI terms) to support clinicians in interpreting AI research. The aim of this paper is to supplement that framework by exploring the key issues for clinicians and researchers to consider in the process of developing an AI model.

The Pushing Sign for Early Skin Tethering in Breast Cancer.

Skin tethering (ST) is regarded as a classical clinical feature of breast cancer. In many cases, ST is not evident on inspection, with the arm raised and skin pinching over the lump. We have observed that pushing the lump in one or another direction may elicit skin dimpling that was not otherwise evident. In these cases, there is normal fat, grossly and histologically, between the tumor and the skin. Thus, the dimpling is not due to cutaneous infiltration. We believe that it is caused by tumor involvement of the ligaments of Cooper and present suggestions as to why it might be so. It may be that this is very early involvement of these ligaments, long before ST becomes very obvious. We report our experience with six such cases.

Minilaparotomy cholecystectomy--an appropriate alternative to laparoscopic cholecystectomy in developing nations.

BACKGROUND: This study reports the experience of performing minilaparotomy cholecystectomy (MC) and assesses the peri-operative outcome of this surgery in the setting of a developing country. METHODS: Data of all patients who underwent minilaparotomy cholecystectomy by a single surgical unit were collected and reviewed. These included demographics, surgical technique used, peri-operative complications and length of hospital stay. Descriptive analyses were done. RESULTS: 476 patients who underwent elective minilaparotomy cholecystectomy in a single surgical unit over a 15 year period were studied. Of these, 84.8% were female. The mean age was 47 years. The most common indication for surgery was symptomatic cholelithiasis with chronic cholecystitis (66%). Mean length of the surgical incision was 4.8 cm and mean operating time was 31 min. Rate of conversion to conventional open cholecystectomy was 4%. Median hospital length of stay was 22 hours. Minor wound infection was the only surgical post-operative complication recorded in 7 patients. Nine patients in the converted group and 3 in the minilaparotomy cholecystectomy group had significant vomiting. There was no mortality. CONCLUSION: The study reinforces the view that minilaparotomy cholecystectomy can be safely and effectively performed with minimal peri-operative complications, and is ideal for developing country settings.

Minimally invasive oesophagectomy: The first case report of a thoracolaparoscopic oesophagectomy done in the Caribbean.

INTRODUCTION: Minimally invasive oesophagectomy is one of the options in the armamentarium of a modern surgeon when faced with treating oesophageal cancer. Trinidad and Tobago has successfully treated a patient using this method. This case report adds to the rich surgical history in the Caribbean. CASE PRESENTATION: Our patient presented with progressive dysphagia, and after being worked up was diagnosed with oesophageal cancer. He underwent neoadjuvant chemotherapy and had a minimally invasive McKeown oesophagectomy done by a fellowship trained, advanced laparoscopic oesophageal and gastric surgeon. CONCLUSION: The patient had an uneventful recovery and was tumor free with excellent quality of life at 4 years, showing that the Caribbean is keeping up with the rest of the surgical world.

The caged bird sign of achalasia: A case series describing a new radiologic sign that can be reliably used in a resource-poor setting to diagnose achalasia.

INTRODUCTION: Achalasia is an uncommon oesophageal motility disorder caused by failed relaxation of a hypertensive lower oesophageal sphincter in response to swallowing. It often manifests clinically with symptoms such as dysphagia, regurgitation, and weight loss. Manometry is considered the gold standard diagnostic test in diagnosing this condition. However, it is not always accessible, especially in the resource-limited setting. Other radiological adjuncts, such as barium oesophagram, often show features that are highly suggestive of achalasia: the bird-beak appearance of the distal oesophagus, and a dilated oesophagus (megaoesophagus) containing food residue, which may then progress to become tortuous (sigmoid) or aperistaltic. Thus, the use of these tests play a significant role in the identification of this condition. CASE PRESENTATION: Three patients were diagnosed with achalasia at the San Fernando General Hospital, Trinidad and Tobago. Together with characteristic symptoms, barium oesophagrams demonstrated features of achalasia, bearing a close resemblance to those of a caged bird. The barium oesophagrams were scrutinized by a fellowship trained, upper GI advanced laparoscopic surgeon, and the consistent features described were noted. CONCLUSION: In the setting where manometry is not accessible, barium oesophagram plays an important role. We propose that recognition of easily identifiable features such as the "caged bird sign of achalasia" on this imaging modality can assist in the diagnosis of this entity.

A Giant Gallstone: The Largest Gallstone Removed Laparoscopically in the World.

Trinidad and Tobago, a small twin island republic off the coast of Venezuela, is leading the Caribbean in laparoscopic surgery. While giant gallbladders are usually difficult to operate on and have a high conversion rate from laparoscopic to open procedure, in Trinidad and Tobago a laparoscopic cholecystectomy involving a giant gallbladder and the largest gallstone ever removed laparoscopically was performed uneventfully.

Totally Laparoscopic Whipple's Operation: Initial Report from the Caribbean.

Oncologic surgery in the Caribbean has evolved over the past decade, with increasing reports of advanced minimally invasive operations being performed. However, the minimally invasive approach has not been used for peri-ampullary lesions. This is because a laparoscopic Whipple's operation is a technically demanding and time-consuming operation. We report the first case of a totally laparoscopic Whipple's operation to be performed in the Caribbean.

A case report of blunt cardiac rupture.

INTRODUCTION: Cardiac rupture is a full thickness laceration of the myocardium that occurs after blunt chest trauma. They are notoriously fatal, with only a handful of patients documented to have survived. These injuries are not commonly associated with low energy chest trauma and may be overlooked as a differential in trauma cases if health care providers are not aware of their possibility. We now report the case of a patient who survived this injury. We believe this is the 16th reported survivor of blunt cardiac rupture. PRESENTATION OF CASE: A 46-year-old construction worker was brought to the emergency department following blunt chest trauma. On arrival he was hypotensive and tachycardic. There was a transient response to intravenous fluid resuscitation. He was found to have a contusion to the left anterior chest wall and left haemothorax on imaging with normal mediastinum. Emergency left anterolateral thoracotomy revealed a pericardial and left ventricular laceration which was repaired. He was weaned off ventilatory support on day 4 post exploration and had an uneventful recovery. DISCUSSION: Survival after blunt cardiac rupture is extremely low. In the past 60 years, only 15 cases have been described where patients survived this injury. They are usually immediately fatal and are caused by high velocity injuries. Our case was interesting because, this injury was due to a low velocity injury resulting in ventricular laceration due to a displaced rib fracture. We believe this is the 16th reported survivor of blunt cardiac rupture. CONCLUSION: It is important, therefore, for first responders to recognize that blunt cardiac rupture can also result from seemingly innocuous, low velocity injuries so that the diagnosis can at least be entertained early. Survival depends on early diagnosis and prompt thoracotomy.

Laparoscopic Completion Cholecystectomy: An Audit from the Americas Hepato-Pancreato-Biliary Association (AHPBA) Caribbean Chapter.

Objective Removal of a gallbladder remnant occasionally becomes necessary when retained stones become symptomatic. Although the laparoscopic approach has been described, it is not yet considered the standard of care. We sought to determine the outcomes after completion cholecystectomies in the resource-poor setting within the Caribbean.  Methods We carried out an audit of the databases from all hepatobiliary surgeons in the Anglophone Caribbean. We identified all patients who had completion cholecystectomy over the five-year period from July 1, 2012 to June 30, 2018. Retrospective chart review was performed to extract the following data: patient demographics, diagnoses, presenting complaints, operative details, morbidity, mortality, and clinical outcomes. Descriptive statistics were generated using Statistical Packaging for Social Sciences (SPSS), version 12.0 (SPSS Inc., Chicago IL) Results There were 12 patients who were subjected to laparoscopic completion cholecystectomy for acute cholecystitis (7), severe biliary pancreatitis (3), and chronic cholecystitis (2) secondary to stones in a gallbladder remnant. There were 10 women and two men at a mean age of 47.4 years (range 32-60; standard deviation (SD) +/-7.81; median 48; mode 52) and a mean body mass index (BMI) of 30.8 Kg/M2 (SD +/-3.81; range 26-38; median 29.5). The mean interval between the index operation and the completion operation was 14.8 months (SD +/- 12.3; range 1-48; median 13; mode 18). Five (42%) patients had their original cholecystectomy using the open approach. Five (42%) index operations were done on an emergent basis and the gallbladder remnant was deliberately left behind in three (25%) index operations. The completion cholecystectomies were all completed laparoscopically in 130.5 minutes (SD +/- 30.5; range 90-180, median 125; mode 125) without any conversions or mortality. There were two minor bile leaks that resolved without intervention through an indwelling drain.  Discussion Completions cholecystectomy can be completed via the laparoscopic approach with good outcomes and acceptable morbidity and mortality rates. The patients derive the same advantages as elective cholecystectomies. Therefore, the laparoscopic approach, when performed by hepatobiliary surgeons with advanced laparoscopic expertise in specialized centers, should be the new standard of care.

Laparoscopic cholecystectomy: analysis of 619 consecutive cases in a Caribbean setting.

INTRODUCTION: Laparoscopic cholecystectomy has become the gold standard in the definitive treatment of symptomatic gall bladder disease. It boasts superior morbidity and mortality and lower complication rates than open approaches. AIM: This study outlines the experiences associated with 619 laparoscopic cholecystectomies performed in Trinidad. METHODS: The records of 619 consecutive patients who underwent the procedure were reviewed. All cases were either performed or supervised by the senior author. The population comprised 511 females and 108 males. The average age was 48.5 years. RESULTS: The commonest indications for surgery were symptomatic cholelithiasis (380 cases) and acute cholecystitis (111 cases). The mean operating time was 34 minutes. The mean length of stay on the ward was 17.45 hours. Mortality was zero. Only 4 cases were converted to open procedures. The commonest postoperative complication was wound-infection. CONCLUSION: In summary, this study demonstrates that laparoscopic cholecystectomy can be performed safely in a Third World setting with results comparable to those internationally.

Single incision laparoscopic surgery from a caribbean perspective.

Conventional laparoscopy with multiple ports has recently gained a strong foothold in the Caribbean, but single incision laparoscopic surgery (SILS) has lagged behind. In this paper, we compare the data on SILS and conventional multi-port laparoscopy in the English-speaking Caribbean.

Mature Cystic Teratoma Hiding in the Retroperitoneum of an Adult.

We report a rare case of a mature cystic teratoma found in the retroperitoneum of a 28-year-old woman with vague symptomatology. We review the radiologic and pathologic features of this rare lesion.

Retrograde Thyroidectomy for preservation of the External Branch of the Superior Laryngeal Nerve: A case series.

BACKGROUND: The external branch of the Superior Laryngeal nerve (EBSLN) is at high risk of injury in surgery for large multinodular goitre (MNG) since the upper pole is high in the neck, well cephalad to the EBSLN. We present a technique of drawing the lobe caudally by retrograde thyroidectomy in order to minimize nerve injury. DESIGN & METHOD: All patients having surgery for benign MNG were included. Cases with previous thyroid surgery, malignant and toxic disease were excluded. The thyroid lobe was mobilized from its inferior aspect and capsular dissection performed cephalad with bipolar or ligasure cautery, lifting the gland off the trachea while separating it from the parathyroids and branches of the inferior thyroid vessels. The ligament of Berry is divided and the entire lobe freed, attached only by the superior pedicle which is drawn caudally well below the EBSLN prior to ligation. Patients were followed for voice change at 24 hours, 7 days and 3 months. RESULTS: Ninety-one consecutive lobectomies were done in 60 patients, 31 bilateral. Forty-four (73%) patients had voice change at 24h, 10 (11%) at 7days and 1 at 3 months. The patient with persistent voice change complained of change in tone but not volume; vocal cords were normal on indirect laryngoscopy. CONCLUSION: Retrograde thyroidectomy is recommended for large MNG where the EBSLN lies well below the upper pole; it minimizes risk to the nerve.

Rare liver tumor: symptomatic giant von Meyenburg complex.

von Meyenburg complexes are hamartomas that arise from intra-hepatic bile ducts. Symptomatic lesions are uncommon and giant lesions are exceedingly rare. When encountered, they should be excised because there are reports of malignant change in large, symptomatic lesions. We report a case of a symptomatic giant von Meyenburg complex.

The steel pan sign of sigmoid volvulus-A case series.

INTRODUCTION: Signs in radiology are usually based on many common objects or patterns that are easily recognizable in everyday life. The objective behind this association is to aid in the understanding and diagnosis of the disease process. These signs can be seen in different imaging modalities such as plain radiograph and computed tomography. PRESENTATION OF CASE: 4 consecutive cases of sigmoid volvulus presented at our tertiary hospital between January 2016 and June 2017. 2 of these cases were managed surgically and others were managed conservatively. The CT scan and abdominal radiographs in these patients were reviewed with consultant radiologist, which bear resemblance to the percussion instrument known as the steel pan. DISCUSSION: The literature has described few radiological signs of sigmoid volvulus in the past. In the following case series, we would like to introduce the "Steel pan Sign", a novel radiological pattern which bears a close resemblance to the percussion instrument known as the steel pan. The Steel pan sign is easier to recognize on CT scan of the abdomen. However, in some cases it can be seen on plain X-Rays. CONCLUSION: The appearance of sigmoid volvulus on CT scans as well as on plain abdominal X-rays bears a significant resemblance to the pattern observed on the face of the Trinidadian steel pan, the recognition of which can aid in the diagnosis of this disease.

Endoscopic thyroid surgery in the Caribbean: A case report of the first clinical experience.

Minimally invasive surgery is rapidly expanding its role in almost all of the surgical sub-specialties. There is also a growing demand of this service as patients became more and more concerned about cosmesis in addition to their original surgery. Although its role in thyroid surgery has already been proven earlier; but it is not yet accepted as a routine approach amongst many thyroid surgeons. There is no reported case of laparoscopic thyroid surgery in the English literature from the Caribbean. We are reporting our first clinical experience in performing laparoscopic thyroid surgery in the Caribbean with a successful outcome.

CT guided appendicectomy incision: A prospective case series.

OBJECTIVE: Several radiological studies have suggested that the base of the Appendix often does not correspond with Mc Burney's point. The aim of our study is to assess the value of using CT localization of the appendicocaecal junction to guide placement of the appendicectomy incision. DESIGN & METHOD: 32 consecutive patients, booked for open appendicectomy were prospectively included in this study. Coronal and axial CT scans with IV contrast were studied to assess site of the appendicocaecal junction. This information was used to guide placement of the incision. RESULTS: 28 out of 32 patients studied, the appendicocaecal junctions were accurately identified. It was noted that the final incision sites were cephalad to Mc Burney's point in 8, at the point in 3 and caudal in 17. In 1 patient, it was necessary to extend the incision medially by 2cm to retrieve the distal Appendix which had been detached through the site of rupture. CONCLUSION: Mc Burney's point often does not correspond to the base of the appendix. We propose that using CT imaging to guide the appendicectomy incision is safe, facilitates locating the Appendix at surgery, minimizes incision size and decreases the need to extend it.

Pancreatic pseudocyst: combined single incision laparoscopic cystogastrostomy and cholecystectomy in a resource poor setting.

Laparoscopic cystogastrostomy is a well-accepted minimally invasive modality to treat pancreatic pseudocysts. There has been one prior report of cystogastrostomy via single incision laparoscopic surgery (SILS) in which specialized instrumentation and access platforms were used.We report the challenges encountered in a low resource setting with the SILS approach to drainage using only standard laparoscopic instruments. To the best of our knowledge this is the second report of SILS cystogastrostomy and the first to be performed in a resource poor setting without specialized instruments or platforms.

Delayed splenic abscess after laparoscopic sleeve gastrectomy.

Splenic abscesses complicating sleeve gastrectomies are extremely rare. We report the fourth recorded case of a splenic abscess; in our case it occurred 10 weeks after sleeve gastrectomy in a 44-year-old man. The clinical presentation was vague but included the triad of fever, left upper quadrant tenderness and leucocytosis. The presence of this triad after sleeve gastrectomy should prompt investigation with contrast CT scans to exclude a splenic abscess.