ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Patients undergoing peripheral surgical procedures were studied before and after induction of halothane anesthesia to determine the interrelationship of functional residual capacity (FRC), closing volume (CV) and alveolar-arterial oxygen difference (A-aDo2). Measurements of FRC, CV, and A-aDo2, (Fto2, = 1.0) were made preoperatively. During anesthesia all patients were ventilated at normal Paco2, with tidal volumes (Vτ) of 5 and 10 ml/kg, the order determined randomly. FRC and A-aDo2were measured 30 and 60 minutes after institution of each tidal volume. FRC during anesthesia was unchanged from preoperative values at either tidal volume. Examining the relationship between preoperative CV and inspiratory lung volume (FRC + Vτ) at the two tidal volumes administered revealed that when FRC exceeded CV, A-aDo2, did not change with anesthesia and was not affected by tidal volume. When CV exceeded inspiratory lung volume, A-aDo2, increased significantly with anesthesia. During anesthesia, changing from a small to a large tidal volume decreased A-aDo2when this increased inspiratory lung volume from below to above CV.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Effects of continuous postoperative pain relief produced by peridural block with bupivacaine on effectiveness of postoperative pulmonary therapy, incidence of pulmonary complications, and duration of convalescence were evaluated. Patients receiving morphine for postoperative analgesia served as controls. Forty patients scheduled for upper abdominal or hip-fracture operations were studied for 72 hours. They were divided into four equal groups: postoperative peridural analgesia with pulmonary therapy, peridural analgesia without pulmonary therapy, morphine analgesia with pulmonary therapy, and morphine analgesia without pulmonary therapy. Preoperative and postoperative variables compared were: chest x-rays, arterial blood gases, calculated alveolar-arterial Po2differences (A-aDo2), vital capacity (VC), peak expiratory Bow rate (PEFR), and duration of convalescence. Patients receiving pulmonary therapy combined with either morphine or peridural analgesia postoperatively did not have a decreased incidence of atelectasis, improvement in blood-gas values, or shorter convalescence times compared with control values (no pulmonary therapy). Twelve of 20 patients in the morphine group and seven of 20 patients in the peridural analgesia group showed x-ray evidence of atelectasis 72 hours after operation. Twenty-four hours postoperatively, the morphine group had decreased arterial blood gases (Pao2Paco2), vital capacity, and peak expiratory flow rate, and an increase in A-aDo2compared with preoperative levels. Corresponding values in the peridural analgesia group did not reveal a significant improvement over the morphine group. The mean convalescence time of peridural analgesia patients was three days shorter than that of the patients receiving morphine (4.8 ± 0.2 vs. 7.8 ± 0.6,P< 0.005).

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

The effects of methoxyflurane on catecholamine secretion by the adrenal medulla and on the pressor effect induced by stimulation of the splanchnic nerve were investigated in cats which had received pentobarbital as a basal anesthetic agent. Inhalation of a methoxyflurane-air mixture (0.3–0.6 per cent methoxyflurane) inhibited both spontaneous catecholamine release and the secretion evoked by splanchnic-nerve stimulation. During inhalation of 0.4 per cent methoxyflurane spontaneous releases of epinephrine and norepinephrine amounted to 17 and 6 per cent of the initial rates, respectively, and releases evoked by neural stimulation were reduced to 30 and 14 per cent of the initial rates. Under these conditions, the pressor effect induced by splanchnic-nerve stimulation was decreased by 42 per cent and, during inhalation of 0.6 per cent methoxyflurane, it was reduced by 79 per cent. These results indicate that the inhibition of catecholamine release by methoxyflurane is at least partially due to a direct effect on the chromaffin cell: the secretion-stimulating effect of acetylcholine, released from the splanchnic nerves, is inhibited. A comparison of these results with those previously obtained for halothane3indicates that both anesthetics act in the same manner on spontaneous catecholamine secretion and on the catecholamine output during splanchnic-nerve stimulation.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

In 30 patients anesthetized with halothane and 60 per cent nitrous oxide, and in 12 cats anesthetized with chloralose and urethane,d-tobo-curarine (dTc) was continuously infused to produce constant 90 per cent depression of twitch height prior to injection of neostigmine or pyridostigmine. Mean times from neostigmine, 0.6, 1.2, or 1.8 mg/m2, or pyridostigmine, 3, 6, or 9 mg/m2administration to peak antagonism (onset time) of dTc were 11.1, 8.5, and 7.1 minutes with neo-stigmine and 15.8, 16.9, and 12.2 minutes with pyridostigmine in man. Mean times from administration of the same doses of neostigmine and pyridostigmine to 50 per cent return to the dTc-depressed twitch (duration of action) were 37.8, 41.0, and 57.2 minutes with neostigmine and 51.4, 78.8, and 83.6 minutes with pyridostigmine in man. The onset and duration of action times also were longer with pyridostigmine than with neostigmine in the cat. The doses of pyridostigmine and neostigmine needed for 50 per cent antagonism of the dTc-induced depression of twitch height were 4.0 mg/m2and 0.92 mg/m2for man and 120 μg/kg and 13 μg/kg for the cat, respectively. Thus, the potency ratio of pyridostigmine to neostigmine is 4.35 (4.0/0.92) in man and 9.3 (120/13) in the cat. We conclude that pyridostigmine has a slower onset and longer duration of action than neostigmine.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

Anesthetic doses of morphine (1–4 mg/kg) were compared with 0.1–1.5 per cent halothane plus 30 per cent nitrous oxide to determine their effects on blood requirements and urinary output in 61 patients during and after open-heart operations. Patients receiving morphine needed significantly more blood during bypass, during the entire operative procedure, and for the first 24 hours postoperatively than did patients anesthetized with halothane-nitrous oxide. Urinary outputs were similar with both anesthetic techniques during all of these periods. The data suggest that morphine may increase total vascular capacitance more than halothane-nitrous oxide does.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

The effects of morphine sulfate on single-unit activities of various dorsal-horn Rexed laminae were studied using an extracellular microelectrode recording technique in decerebrate spinal cats. Morphine sulfate, 0.5, 1, and 2 mg/kg, iv, suppressed in a dose-related manner spontaneous single-unit activities in Rexed laminae I and V, known to respond principally to noxious stimuli, but did not affect spontaneous activities in laminae IV and VI, known to respond to non-noxious stimuli. Morphine sulfate, I mg/kg, iv, also suppressed unit activities of laminae I and V evoked by noxious cutaneous stimuli by 35.5 ± 7.1 and 48.2 ± 4.0 (&OV0335; ± 1 SE) per cent, respectively. The selective action of morphine on dorsal horn nociceptors may partially explain the analgesic action of morphine at the spinal level.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID

摘要:

To elucidate the mechanism of cardiac stimulation during ketamine anesthesia, myocardial forcevelocity relationships were determined in six subjects whose heart rates were controlled by atrial pacing. Contractility changes were seen in three patients and preloading effects in the other three. It is not possible to predict which effect will predominate in the surgical population. However, marked preloading would be detrimental to the patient already utilizing that mechanism to maintain cardiac compensation.

ISSN:0003-3022    

出版商:OVID    

年代:1974

数据来源: OVID