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Antihypertensive drugs interfere with hemodynamic adjustments and can cause profound cardiovascular collapse when a patient is subjected to the stress of anesthesia and surgery. They constitute an insidious hazard to surgical patients. In patients who have received antihypertensive medication the primary problem is to determine the availability of the intrinsic catechol amines and the patient's ability to respond to them. This problem is solved by using the ephedrine response test (ERT). The test consists of 2 intravenous injections of ephedrine; the first injection of 10 mg. is followed promptly by additional 5 mg. If the ERT does not elicit a rise of at least 20 mm. Hg in blood pressure, the patient is believed to be unprepared for the cardiovascular stress of general, spinal, or spidural anesthesia.

Eleven consecutive cases of pheochromocytoma were successfully diagnosed and surgically cured. The rational anesthetic management of a patient with pheochromocytoma should be based on a firm foundation of applied pharmacology. Cardiovascular control is best maintained symptomatically using phentolamine (Regitine) hydrochloride to control excessive hypertension, and with appropriate vasopressors, whole blood or plasma and possible cortisone acetate, to combat hypotension after the tumor is removed. The advantages associated with the transabdominal surgical approach are stressed. The patient with pheochromocytoma can tolerate anesthesia and the associated surgical procedure well through the combined efforts of the anesthesiologist and surgeon in executing their specific responsibilities.

To arrest the progress of tetanus in a patient two main objectives must be attained, namely, the neutralization of circulating toxin and the elimination of its source. Meanwhile the neuromuscular manifestations must be controlled. Drugs used for this purpose are generally depressants of the central nervous system. If they hamper cardiovascular and respiratory function their use is illogical. The regimen advised by the authors employs a sedative (either secobarbital or pentobarbital) and a muscle relaxant (methocarbamol) together with chlorpromazine, which is believed to potentiate the sedative-relaxant effects of the other two drugs. Strict attention to pulmonary ventilation is essential. Tracheotomy should be performed early in severe cases. The aspiration of tracheobronchial secretions must be prevented, and it may be necessary to assist respiration by mechanical means. In the prevention of asphyxia the anesthesiologist can play a vital role.

During actual and simulated spinal anesthesia in 21 term gravid ewes, induced maternal hypotension was associated with a proportionate decrease in uterine blood flow (UBF). Under these circumstances, vasopressor drugs administered intravenously restored maternal blood pressure (MBP) to normal without improving uterine blood flow. However, rapid infusions of 5% dextrose or dextran solution significantly improved both MBP and UBF proportionately. These results indicate that the prophylactic or therapeutic use of vasopressor agents in conjunction with spinal or caudal anesthesia during pregnancy is contraindicated. Rather, therapy designed to increase effective circulating blood volume should be initiated. This includes a rapid intravenous infusion of dextrose solution, elevation of the legs, and displacement of the uterus to the left to reduce vena caval obstruction and increase venous return to the heart.

NEUROLEPTANALGESIA is based upon the use of a tranquilizer and a narcotic administered intravenously to produce a state of psychic withdrawal and profound analgesia.1 Several series of tranquilizers and narcotics have been investigated in Europe; those currently available for investigation in the United States, droperidol2 and fentanyl citrate,3 represent the most evolved of these so far.Droperidol, a butyrophenone, is a potent tranquilizer which produces in the patient a state of calm, disinclination to move, and "disconnection" from the surroundings. It has an α-adrenergic blocking effect, which offers some protection against shock, leads to good peripheral perfusion, and "unmasks" hypovolemia. It also protects against epinephrine-induced arrhythmias, and has an antiemetic effect.Droperidol may cause hypotension by virtue of its α-adrenergic blocking effect and peripheral vasodilatation, particularly when the drug is administered rapidly and in the presence of hypovolemia. The hypotension is usually transitory in the former case,