Intra-operative carcinoid crisis: Revised anaesthesia management

Shifting Paradigms in the Pathophysiology and Treatment of Carcinoid Crisis

Carcinoid crisis is a potentially fatal condition characterized by various symptoms, including hemodynamic instability, flushing, and diarrhea. The incidence of carcinoid crisis is unknown, in part due to inconsistency in definitions across studies. Triggers of carcinoid crisis include general anesthesia and surgical procedures, but drug-induced and spontaneous cases have also been reported. Patients with neuroendocrine tumors (NETs) and carcinoid syndrome are at risk for carcinoid crisis. The pathophysiology of carcinoid crisis has been attributed to secretion of bioactive substances, such as serotonin, histamine, bradykinin, and kallikrein by NETs. The somatostatin analog octreotide has been considered the standard of care for carcinoid crisis due to its inhibitory effect on hormone release and relatively fast resolution of carcinoid crisis symptoms in several case studies. However, octreotide's efficacy in the treatment of carcinoid crisis has been questioned. This is due to a lack of a common definition for carcinoid crisis, the heterogeneity in clinical presentation, the paucity of prospective studies assessing octreotide efficacy in carcinoid crisis, and the lack of understanding of the pathophysiology of carcinoid crisis. These issues challenge the classical physiologic model of carcinoid crisis and its common etiology with carcinoid syndrome and raise questions regarding the utility of somatostatin analogs in its treatment. As surgical procedures and invasive liver-directed therapies remain important treatment modalities in patients with NETs, the pathophysiology of carcinoid crisis, potential benefits of octreotide, and efficacy of alternative treatment modalities must be studied prospectively to develop an effective evidence-based treatment strategy for carcinoid crisis.

Carcinoid Crisis: A Misunderstood and Unrecognized Oncological Emergency

Carcinoid Crisis represents a rare and extremely dangerous manifestation that can occur in patients with Neuroendocrine Tumors (NETs). It is characterized by a sudden onset of hemodynamic instability, sometimes associated with the classical symptoms of carcinoid syndrome, such as bronchospasm and flushing. Carcinoid Crisis seems to be caused by a massive release of vasoactive substances, typically produced by neuroendocrine cells, and can emerge after abdominal procedures, but also spontaneously in rare instances. To date, there are no empirically derived guidelines for the management of this cancer-related medical emergency, and the available evidence essentially comes from single-case reports or dated small retrospective series. A transfer to the Intensive Care Unit may be necessary during the acute setting, when the severe hypotension becomes unresponsive to standard practices, such as volemic filling and the infusion of vasopressor therapy. The only effective strategy is represented by prevention. The administration of octreotide, anxiolytic and antihistaminic agents represents the current treatment approach to avoid hormone release and prevent major complications. However, no standard protocols are available, resulting in great variability in terms of schedules, doses, ways of administration and timing of prophylactic treatments.

Incidental Diagnosis of Carcinoid Disease by Intraoperative Transesophageal Echocardiography and Subsequent Discovery of a Neuroendocrine Tumor during Cardiac Surgery

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Carcinoid heart disease typically involves the right-sided valves of the heart.

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Carcinoid valves are fixed and retracted with limited mobility.

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Pathognomonic appearance of valves increases carcinoid likelihood.

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Carcinoid diagnosis has intraoperative implications.

Carcinoid Syndrome: A Review

Carcinoid syndrome (CS) is a paraneoplastic syndrome caused by the release of serotonin and other substances from well-differentiated neuroendocrine tumors (NETs). The hallmark symptoms of carcinoid syndrome are flushing and diarrhea; atypical signs and symptoms can include wheezing, abdominal pain, valvular heart disease, telangiectasias, pellagra, and the complications of mesenteric fibrosis, including ureteral obstruction, bowel obstruction, and bowel ischemia. These symptoms are mediated by the release of serotonin (5-HT), histamine, kallikrein, prostaglandins, and tachykinins. The diagnosis of CS requires these symptoms and corresponding elevations in lab tests. Treatment options include surgery and medical management with somatostatin analogs.