Perioperative Management of Patients With Hereditary Angioedema With Special Considerations for Cardiopulmonary Bypass.

Hereditary angioedema (HAE) is a rare autosomal dominant disorder mostly due to the deficiency of C1-esterase inhibitor (C1-INH). Reduced C1-INH activity below ~38% disrupts homeostasis of bradykinin (BK) formation by increasing kallikrein activation and causes recurrent angioedema attacks affecting the face, extremities, genitals, bowels, oropharynx, and larynx. HAE symptoms can be debilitating and potentially life-threatening. The recent clinical developments of biological and pharmacological agents have immensely improved acute and long-term care of patients with moderate-to-severe HAE. The therapies are given as on-demand and/or prophylaxis, and self-administration is highly recommended and performed with some agents via intravenous or subcutaneous route. Perioperative clinicians need to be familiar with the symptoms and diagnosis of HAE as well as available therapies because of the potential need for airway management, sedation, or anesthesia for various medical and surgical procedures and postoperative care. Cardiovascular surgery using cardiopulmonary bypass is a unique condition in which heparinized blood comes into direct contact with an artificial surface while pulmonary circulation, a major reserve of angiotensin-converting enzyme (ACE), becomes excluded. These changes result in systemic kallikrein activation and BK formation even in non-HAE patients. The objectives of this review are (1) to review pathophysiology of HAE and laboratory testing, (2) to summarize pertinent pharmacological data on the prophylactic and on-demand treatment strategies, and (3) to discuss available clinical data for perioperative management in cardiovascular surgery.

Management of patients with hereditary angio-oedema in dental, oral, and maxillofacial surgery: a review.

Hereditary angio-oedema (HEA) is an autosomal dominant, life-threatening genetic disorder that is caused by insufficiency or dysfunction of the C1 esterase inhibitor that develops coincidentally with recurrent oedema in the skin, internal organs, and upper respiratory tract. Increased production of bradykinin secondary to increased plasma kallikrein activity is the primary cause of attacks. Dental procedures cause emotional stress and mechanical trauma and may also initiate attacks. The most feared complication is asphyxiation as a result of laryngeal oedema. Cases that resulted in death after tooth extraction have been reported, so dentists and oral and maxillofacial surgeons should take maximum care in the treatment of patients with HAO, consult with the patient's doctor, and ensure that prophylaxis is given before the procedure. They should work as atraumatically as possible and use procedures to minimise stress. In the event of an attack of HAO, despite all the correct measures having been taken, the procedure should be terminated immediately and treatment of the attack started as soon as possible. The first drugs for the treatment of acute attacks are C1-INH (C1 inhibitor), ecallantide, or icatibant.

C1-esterase inhibitor for short-term prophylaxis in a patient with hereditary angioedema with normal C1 inhibitor function.

Hereditary angioedema with normal C1-esterase inhibitor (HAE-nC1INH) perioperative is a rare condition which could have potential disastrous ramifications for the anesthesiologist in the perioperative period. However, there is limited evidence and/or guidelines on the optimal way to manage these patients. We present the case of a patient with HAE-nC1INH who was successfully managed in the perioperative period with plasma derived C1-esterase inhibitor (pdC1INH). A 29-year-old woman with a diagnosis of HAE-nC1INH presented to the preoperative consultation in preparation for an upcoming total thyroidectomy. She had a 14-year history of ongoing lip and facial edema sometimes necessitating emergency department visitation. Close consultation with her immunologist, transfusion medicine specialists, and anesthesia care providers allowed for a preoperative plan to provide the patient adequate prophylaxis. Both pdC1INH and tranexamic acid were given preoperatively. The patient underwent surgery with no complications. A multidisciplinary team of clinical immunologists, transfusion medicine specialists, and anesthesiologists facilitated the successful perioperative management of a patient with HAE-nC1INH; pdC1INH may a suitable prophylactic perioperative therapy for this rare patient population.

Perioperative management of tooth extractions for a patient with hereditary angioedema.

Hereditary angioedema (HAE) is a rare genetic disorder that causes a deficiency in or dysfunction of C1 esterase inhibitor (C1-INH) and is clinically characterized by sudden and recurrent attacks of angioedema. Although almost any part of the body can be affected, HAE is of greatest concern and can be life-threatening when the upper airway is involved, particularly the larynx (laryngeal attack). HAE attacks can be triggered by physical or psychological stress or can arise spontaneously without any apparent trigger. Dental treatments and routine oral surgical procedures, such as tooth extraction, abound with factors that can trigger an attack of HAE. Indeed, several cases of death resulting from HAE attacks have been reported after such procedures. Therefore, patients with HAE are of special concern in dentistry and require precautionary preparations before treatment. This report describes the successful management of tooth extractions in a patient with HAE who was at high risk of an HAE-induced laryngeal attack.

Managing hereditary angioedema patients undergoing otolaryngeal procedures.

BACKGROUND: Hereditary angioedema (HAE), a rare autosomal dominant disorder, is characterized by repeated attacks of swelling of the skin, gastrointestinal tract, face, larynx, and other organs. In most cases it is caused by low levels of functional C1 esterase inhibitor (C1-INH), a serine protease inhibitor that plays important regulatory roles in the complement, contact, and fibrinolytic pathways. METHODS: Lack of functional C1-INH results in excessive release of bradykinin, which triggers vasodilation, vascular permeability, and edema. Most attacks are mild and self-limiting, but untreated laryngeal attacks may cause rapid asphyxiation and death. Potential triggers of laryngeal attacks include trauma to or manipulation of the face, mouth, or upper airway. Therefore, before performing such a procedure in a patient with HAE, the otolaryngologist should consult with the patient, the physician managing the HAE, and the anesthesiologist and make appropriate preparations for prevention and/or treatment of an attack. RESULTS: Current World Allergy Organization and European guidelines recommend the use of i.v. plasma-derived C1-INH replacement for short-term prophylaxis of angioedema attacks. Other effective options include danazol given for several days before and after the procedure and fresh-frozen plasma, but these may not be as effective as C1-INH and may be associated with a high rate of adverse events. CONCLUSION: Acute attacks, which may occur many hours after a procedure, may be treated with C1-INH; icatibant, a bradykinin B2-receptor antagonist; or ecallantide, a kallikrein inhibitor, all of which have been shown to reduce the duration and severity of HAE attacks.

Perioperative management of a patient with hereditary angioedema during off-pump coronary artery bypass graft surgery.

The case of a patient with hereditary angioedema (HAE), a rare, life-threatening disorder caused by reduced activity of the C1 esterase inhibitor, and requiring off-pump coronary artery bypass graft (OP-CABG) surgery, is presented. Perioperative management of patients with HAE who undergo complex cardiac surgical procedures are discussed, including an OP-CABG surgical approach to decrease complement activation, fresh-frozen plasma administration to increase C1 esterase inhibitor activity, and administration of reduced doses of heparin and protamine to minimize heparin-protamine complex formation.

Modern preoperative and intraoperative management of hereditary angioedema.

Hereditary angioedema (HAE), deficiency of C1 esterase inhibitor, poses a risk of airway compromise during trauma, including surgery, due to activation of the complement cascade. Classical surgical management includes emergent/slash tracheostomy and cricothyrotomy, associated with high complication rates. We provide here an evidence-based review of available medical literature to construct guidelines for managing patients with HAE pre- and intra-operatively. We also describe our experience with a patient for whom we cared using these guidelines. Our objective was to explain new preventive measures to prevent airway compromise in HAE and their level of evidence for averting potential therapeutic misadventure. We analyzed PUBMED literature regarding airway management and etiology of angioedema and its prevention, followed by application of guidelines based on these data in a patient with HAE undergoing inguinal hernia repair. An analysis of contemporary literature yielded key points: (1) using a Cook Exchange catheter to facilitate re-intubation, (2) measuring cuff leak pressure to verify whether airway pressure had increased during surgery, (3) visualizing the airway directly using a fiberoptic laryngoscope connected to a digital flat-screen monitor for real-time assessment, (4) following conventional dictum to double stanozolol dosages 2 weeks before admission, (5) administering fresh frozen plasma pre- and intraoperatively, and (6) preparing recombinant C1 esterase inhibitor for instantaneous intraoperative use; and using FDA-approved human-derived C1-esterase inhibitor prophylactically. Biotechnology in the form of novel but currently available and in-practice medical devices, as well as new therapeutic agents, have expanded the armamentarium for safely managing patients with HAE pre- and intraoperatively.

Management of hereditary angioedema during off-pump coronary arterial surgery.

A 62-year-old man presented with coronary artery disease complicated by a history of hereditary angioedema. In preparation, extensive consultation and literature review were completed. Close cooperation between immunology, anesthesiology, and cardiac surgery teams, as well as an off-pump technique led to a favorable outcome.