Value of skin tests for the choice of a neuromuscular blocking agent after an anaphylactic reaction

We report a grade III allergic hypersensitivity reaction occurring in a 72-year-old patient immediately after anaesthesia induction. Anaphylaxis to cisatracurium was diagnosed on clinical symptoms, biological tests and positivity of the cutaneous tests to this neuromuscular blocking agent. Five days after this allergological assessment, rocuronium, a muscle relaxant for which skin tests appeared negative was used during surgery without adverse effects. The authors underline the value of a detailed allergological assessment to identify the pathophysiologic mechanism, the culprit drug and to propose a safer alternate drug that might be used.     

The neuromuscular blocking properties of AH 8165 during halothane anaesthesia

The time to onset, duration, time for reversal, and dose required to abolish twitch response for AH 8165 have been investigated. The drug is shown to be a rapidly acting agent, with a duration of action similar to pancuronium.     

Pulseless electrical activity during caesarean delivery under spinal anaesthesia: a case report of severe anaphylactic reaction to Syntocinon

Anaphylactoid reaction to Syntocinon is rare, but has been described in the literature. The reactions described include patchy erythema, hypotension, bronchospasm and oxygen desaturation, but pulseless electrical activity following Syntocinon has not been reported. We present the case of a 34-year-old primigravida with essential hypertension, gestational diabetes and hypothyroidism with a twin pregnancy following in vitro fertilization. During elective caesarean delivery she developed a severe anaphylactic reaction to Syntocinon leading to pulseless electrical activity.     

Severe anaphylactic reaction to metamizol during subarachnoid anesthesia

A 59-year-old man with no relevant medical history underwent a right saphenectomy under subarachnoid anesthesia with mepivacaine. Administration of intravenous metamizol for postoperative analgesia was followed by severe anaphylactic reaction with respiratory failure and ventricular fibrillation. The patient recovered after orotracheal intubation and defibrillation. High serum tryptase levels 2 and 6 hours after the episode and positive skin prick tests confirmed the diagnosis of anaphylactic reaction mediated by immunoglobulin-E antibodies. Anaphylactic reactions to metamizol may be more common than would appear based on reports in the literature. When signs present suddenly with cardiovascular or respiratory involvement, symptomatic treatment should be started even in the absence of cutaneous or mucosal signs and allergy tests should be carried out immediately.     

Rocuronium anaphylaxis and multiple neuromuscular blocking drug sensitivities

PURPOSE: To report a case of anaphylaxis to rocuronium and the sensitivities to multiple neuromuscular blocking drugs in a patient with no previous exposure to this group of drugs. We describe the current recommendations for both intraoperative and postoperative testing of these patients. CLINICAL FEATURES: A 36-yr-old man was admitted for repair of a ruptured Achilles tendon. Following induction of general anesthesia with fentanyl and propofol, 60 mg of rocuronium were given to facilitate tracheal intubation. He immediately became profoundly hypotensive with impalpable pulses, and blood pressure could not be recorded. Airway pressure increased markedly, and hand ventilation of the lungs became very difficult. His airway was secured and he was successfully resuscitated with 3 mg epinephrine and three litres crystalloid and colloid intravenous fluid therapy. His recovery in the intensive care unit was uneventful and the operation was performed four days later under spinal anesthesia. Subsequent skin prick testing, performed six weeks later, demonstrated strong positive weal and flare reactions to rocuronium, vecuronium and pancuronium, and some cross-reactivity with the benzylisoquinolinium group of muscle relaxants. CONCLUSION: Muscle relaxants are responsible for 61.6% of cases of anaphylaxis during general anesthesia. Cross-reactivity is common, as this group of drugs share a quaternary ammonium group. It is mandatory that patients be tested for both the agent responsible and cross-reactivity following an anaphylactic response. We suggest a protocol for investigation of suspected anaphylaxis.     

Anaphylaxis during anesthesia--especially from neuromuscular blocking agents

Among all drugs used for general anesthesia, neuromuscular blocking agents (NMBAs) seem to play a predominant role in the incidence of severe adverse reactions. The overall incidence of perioperative anaphylaxis is estimated at 1 in 10,000-20,000 anesthetic procedures, whereas it is estimated at 1 in 6,500 administrations of NMBAs. After anaphylaxis, allergologic assessment is essential to identify the offending agent and to prevent recurrences. The estimated sensitivity of skin tests for muscle relaxants is approximately 94% to 97%. Prick testing is advised for the diagnosis of the NMBAs responsible for an anaphylactic reaction, and intradermal testing is preferred when investing cross-reaction. The choice of the safest possible anesthetic agents should be based on the result of a rigorously performed allergologic assessment.     

Subsequent general anaesthesia in patients with a history of previous anaphylactoid/anaphylactic reaction to muscle relaxant

Of 151 patients with a possible anaphylactoid/anaphylactic reaction to a muscle relaxant investigated over a 20-year period, follow-up for any subsequent general anaesthesia was complete in 145 (96%). One hundred and twenty-two anaesthetics in 72 patients were documented. There were no anaesthetic-related deaths. No subsequent reactions were seen if muscle relaxants were not used in the subsequent anaesthetic, nor were they in patients with severe reactions if the original intradermal test had been equivocal or negative. In the patients with a severe reaction and a positive intradermal test to one or more muscle relaxants, six out of 40 later anaesthetics using muscle relaxants were associated with clinical problems, three being probable anaphylactic reactions, whilst three were minor. Intradermal testing should be performed prior to surgery in this group of patients for the muscle relaxant(s) planned, or an anaesthetic technique which avoids relaxants should be used. This review should encourage other centres to undertake similar follow-up.     

Unintentional neuromuscular blocking agent injection during an axillary brachial plexus nerve block

OBJECTIVE: We describe the consequences of an unintentional injection of atracurium instead of ropivacaine during an axillary brachial plexus nerve block. CASE REPORT: A 79-year-old woman was scheduled for wrist fracture repair. An axillary brachial plexus block was performed by use of a nerve stimulator. Twenty milliliters of 0.5% ropivacaine with 1:200,000 epinephrine was injected on the radial and then on the median nerves. Two minutes later, the patient became dyspneic and was unable to elevate her head from the pillow. A check of the syringes revealed that one contained 50 mg of atracurium instead of 0.5% ropivacaine. After IV propofol was administered, the trachea was intubated and controlled ventilation started. At the end of surgery (more than 2 hours later), reversal of residual neuromuscular block was performed. The motor and sensory brachial plexus block completely recovered 12 hours after the initial bolus injection. No clinical neurological deficit was reported afterward by the patient. CONCLUSIONS: Unintentional injection of atracurium mixed with ropivacaine during axillary brachial plexus block leads to complete body paralysis that requires general anesthesia and mechanical ventilation. Recovery was complete without any neurological sequela. An analysis of the chain of events that led to the error suggests some recommendations to improve our daily practice.     

Why should I change my practice of anaesthesia: neuromuscular blocking agents

BACKGROUND: Recently, four neuromuscular blocking agents have been introduced into clinical practice. The drug companies claim that these new drugs offer several important advantages. But is this true? Do the new neuromuscular blocking agents add anything to our clinical practice, and will their introduction really benefit our patients? Or will it only benefit the economy of the companies? PURPOSE OF THE LECTURE: In this lecture I shall try to update you on these new drugs and give you my personal bias on when to use the different (new and old) neuromuscular blocking agents.     

Failure to influence hypotension during spinal anaesthesia with a limb tourniquet

Fourty patients undergoing total hip replacement under spinal anaesthesia were allocated randomly to have a thigh tourniquet inflated after exanguination of the leg not being operated on or to act as controls. Significant hypotension (systolic arterial pressure < 70 mm Hg) was treated with i.v. ephedrine in 6 mg boluses. There was no significant difference between the two groups with respect to systolic blood pressure or requirement of ephedrine, during the hour that the tourniquet was applied or the period immediately after the removal of the tourniquet.