The clinical and biological signs of histamine release during induction of anaesthesia and preparation of the surgical patient: A farewell party for the classical manifestations of anaphylaxis

Incidence and clinical importance of perioperative histamine release: randomised study of volume loading and antihistamines after induction of anaesthesia. Trial Group Mainz/Marburg

Although histamine release is recognised as a common event during anaesthesia and surgery, few clinicians judge the resultant cardiorespiratory disturbances serious enough to warrant prophylaxis with antihistamines. We have assessed the incidence and importance of histamine release in a randomised 2 x 2 factorial study. 240 patients representing a routine throughput of major general surgery were studied during a standardised induction of anaesthesia and preoperative loading of the circulation with either Ringer solution or Haemaccel-35, with or without antihistamine prophylaxis with dimetindene (H1) plus cimetidine (H2). Cardiorespiratory disturbances were graded as detectable, clinically relevant, or life-threatening from observers' records of the anaesthesia and the actions taken by the anaesthetists. Disturbances that were accompanied by significant rises in plasma histamine were further designated histamine-related, and those that were not were designated histamine-unrelated. Anaesthetists, observers, and designators were blinded to whether or not the patients had received antihistamines and to which solution was used for circulatory volume loading. Clinically relevant or life-threatening histamine-related disturbances occurred in 8% of the patients who after induction of anaesthesia received Ringer without antihistamines, in 26% of those who received Haemaccel without antihistamines, and in 2% or less of those who received antihistamines (p < or = 0.0001). There were 4 life-threatening histamine-related disturbances, all in patients who received Haemaccel without antihistamines (p < 0.01). Histamine-unrelated disturbances occurred in 16% overall, with no obvious effect of Haemaccel or antihistamines. The histamine-related disturbances under anaesthesia were remarkable for their severity (even with small rises in histamine concentrations), for the prevalence of bradycardia, and for the absence of skin signs. Their likelihood and severity were increased in patients with tumours. The results of the trial make a case for routine prophylaxis with antihistamines as part of anaesthetic management.

The Australian Incident Monitoring Study. Clinical anaphylaxis: an analysis of 2000 incident reports

There were 57 reports of possible allergic reactions in the perioperative period in the first 2000 incidents reported to the Australian Incident Monitoring Study. These were examined and classified with respect to presentation, clinical course, agents implicated and management strategies employed. Reactions were graded as to probability of allergic aetiology and severity of systemic disturbance. Two deaths were reported. A method of determining an "allergy score" was devised as an indication of which reactions may be most deserving of further investigation.

Perioperative nonspecific histamine release: a new classification by aetiological mechanisms and evaluation of their clinical relevance

As a consequence of the performance of a randomized controlled clinical trial on perioperative histamine release and cardiovascular and respiratory disturbances, several types of increases in plasma histamine had to be distinguished instead of only two which existed at the beginning of the study: drug-induced allergic and pseudoallergic reactions. First of all, the new classification by aetiology (clinical epidemiology) was derived from a meta-analysis (secondary analysis) of the most recent literature. According to that histamine release in the perioperative period has several, different causes and is involved in several, different disease manifestations. A clear distinction (classification), however, is necessary if histamine release as an unwanted (adverse) effect has to be recognized, value judged according to its clinical relevance and therefore also prevented by histamine antagonists. Histamine release by neuro-endocrine and neuro-inflammatory mechanisms, cytotoxic histamine release and local, cytokine induced histamine release have been distinguished from pseudoallergic histamine release, but its functions are not yet clear. It has been analysed in prospective trials which used special clinical situations as models: patients on a normal ward or before and during upper GI endoscopy without premedication, but also in specific phases of laparoscopic cholecystectomy (trocar phase and dissection phase). Their existence in the clinical reality is now very likely, but new trials must investigate the pathophysiological effects such as in metabolism, coagulation, pulmonary haemodynamics (shunt volume) and gastric acid secretion. Histamine release by pseudoallergic mechanisms, however, was identified in the very vulnerable post-induction phase of anaesthesia up to skin incision. Its incidence was much higher than ever expected and its clinical relevance was demonstrated by the severity of reactions and the intervention strategies of the anaesthetists who were blinded concerning the type of the plasma substitute given and the prophylaxis with antihistamines. Pseudoallergic histamine release was clearly unwanted (adverse). Its occurrence in the other phases of anaesthesia has to be further evaluated in the tedious procedure of data analysis of the Mainz-Marburg-trial. The overall incidence of histamine release in the trial was so incredible high (72% of all patients, some of them with up to 4 episodes of histamine release) that a distinction between pseudoallergic (unwanted) and other types of histamine release (possibly less unwanted or even beneficial) is urgently needed. In the phase of steady state (maintenance) of anaesthesia the H1-(+)H2-prophylaxis was highly effective. Further analysis must show whether this is also the case during the phases of induction of anesthesia.(ABSTRACT TRUNCATED AT 400 WORDS)