[Physiopathology of anaphylactic and anaphylactoid shock. A cooperative retrospective study]

The pathophysiology of anaphylactic and anaphylactoid shock states suggests that the rapidly initiated, intensive therapeutic measures to be taken must involve: breathing (ventilation) of (with) 100% oxygen, continuous or semi-continuous sympathicomimetic therapy (epinephrine, isoprenalin, orciprenalin) avoiding excessive single doses, rapid intensive volume substitution, control of metabolic acidosis, bronchospasmolytic therapy, in case of laryngospasm intubation, if not possible coniotomy or transtracheal punction. In case of circulatory arrest possibly also cardiac massage, defibrillation, lidocain, cardioversion. In a retrospective study 91 cases of anaphylactic and anaphylactoid shock were analyzed. Cutaneous vascular changes. Vasodilation was reported in 30 cases, vasoconstriction in 15 cases. Hypovolemia. CVP as measured in 23 cases was less than or equal to 2 cmH2O in 12 cases; in 4 of these cases the early finding and in 2 a rather low hematocrit are in favour of venous blood sequestration. In 2 cases the increase of the hematocrit suggests an extravasation of as much as 1,2 and 1,81 of plasma, respectively. Increase of pulmonary arterial pressure. CVP increased in 2 out of 9 cases suggesting a high pulmonary arterial pressure. Decreased cardiac output (CO). In 3 cases CO as determined in a late shock phase diminished by 37--55%. Blood gas changes. PaO2 was as low as 47--61 mmHg in 4 out of 8 cases, PaCO2 being 29--34 mmHg in 2 of them. It suggests an insufficient oxygen transport. Myocardial involvement. Arrhythmias (non sinus-) were found in 38 cases, of which 14 ventricular arrhythmia and 13 asystole. Serious wave deformation concerned QRS (3), AV-block (2), intraventricular blocks (4). 5 times the reaction resulted in myocardial infarction. A localized coronary spasm in anayphylactic shock was observed during a coronary angiography. Respiratory impairment. Severe respiratory impairment was associated with anaphylactic and anaphylactoid shock in 31 cases (26 bronchospasm, 4 apnea, 1 laryngospasm).