Carcinoid crisis or carcinoid syndrome – Carcinoid tumors can cause both of these, which lead to wide variability in blood pressures. Carcinoid crisis is life-threatening and manifests as severe flushing, and dramatic changes in blood pressure, cardiac arrhythmias, and bronchoconstriction. The primary goal is to avoid the release of vasoactive substances from the tumor.

Pretreat with octreotide – The typical dose is 50-150 mcg SQ. Infusion of Octreotide is recommended to be infused perioperatively at 100 mcg/hr. Octeotide inhibits the release of vasoactive agents from carcinoid tumors

Hypotension – Treat with phenylephrine, vasopressin and/or calcium chloride. These drugs avoid beta activation. Refractory hypotension unresponsive to Octreotide may be treated with Aprotinin (a kallikrin inhibitor)

Hypertension – Treat with beta blockers (eg. esmolol, labetolol), alpha antagonists, and consider deepening anesthesia where possible.

GI symptoms – treat with 20 mg IV Pepcid preoperatively and use and NG tube intraoperatively

Anesthesia type – General anesthesia is preferred over neuraxial anesthesia to avoid sympathectomy.

Avoid histamine release – common drugs that lead to the release of histamine are morphine, atracurium, mivacurium, thiopental, and pancuronium.

Warm the patient – hypothermia can cause catecholamine-induced vasoactive mediator release

Avoid sympathetic release – anxiety (treat with Versed), hypoxia, hypercarbia, light anesthesia, pain, and hypothermia. Common drugs that lead to the release of catecholamines are Ketamine, Ephedrine, and Succinylcholine.

Induction of anesthesia – has been known to precipitate a carcinoid crisis. Ensure adequate depth of anesthesia prior to intubation.

Foley catheter, A-line, CVP, 2 Large-bore IV’s – should all be strongly considered to closely monitor and maintain fluid output and hemodynamics. Ideally preoperatively optimize electrolytes and fluid status – 80% of patients with carcinoid tumors will have diarrhea.

Patient is typically kept dry – usually 2 liters max administration. Consider using albumin.

Extubate awake – anticipate excessive drowsiness on emergence due to high serotonin levels.

Closely control pain – this is, like most of the implications above, to control the wide fluctuations in hemodynamics.

ICU transfer – Patient will be transferred postoperatively to the ICU and weaned off of octreotide (usually over the first week)

These tumors most often originate in the GI tract (66%), pancreas, thymus, liver, and lungs. The small intestine is the most common site of origin in the GI tract.

Enterochromaffin cells within the tumor are capable of releasing bioactive humoral agents (hormones). The 3 most common are serotonin, histamine, and kinin peptides.

The liver is normally responsible for filtering these agents. However, carcinoid syndrome may occur when these agents are released from tumors that do not drain into the portal system and thereby bypass inactivation by the liver. About 10% of patients with carcinoid tumors develop carcinoid syndrome

Serotonin excess may cause vasoconstriction OR vasodilation, increase gut motility, vomiting, bronchospasm, hyperglycemia, and prolonged emergence from anesthesia.

Histamine excess may cause bronchospasm and flushing. This hormone is most commonly released from carcinoids found in the foregut.

Kinin (bradykinin) excess produces vasomotor relaxation which leads to profound hypotension, flushing, and bronchospasm.

Collectively, the most common signs and symptoms in order of most frequent to least frequent are these: Flushing, diarrhea, cardiac valvular lesions, cramping, telangiectasia, wheezing, peripheral edema, cyanosis, pellagra, and arthritis

These tumors may metastasize to other parts of the body. The most common site of metastasis is the liver.

Diagnosis: 24-hour urinary sample demonstrating 5-HIAA measurement > 30 mg. Flushing and diarrhea is very common. Diarrhea is found in 80% of patients with this condition.

Patients are most often diagnosed in their early 60’s. More common amongst African Americans and females. 8000 new cases each year