Ma zui xue za zhi = Anaesthesiologica Sinica最新文献

Infraclavicular approach to the brachial plexus provides adequate anesthesia of the entire arm. Local anesthetics can be deposited over cords and branches of brachial plexus above the formation of musculocutaneous and axillary nerves. The approach can also easily block ulnar segment of medial cord and intercostobrachial nerve, which helps preventing tourniquet pain. However, distance to the plexus is deeper than the other approaches so that current blind method using anatomical landmarks requires anesthesiologists' delicate manipulation and experience. Through ultrasonography, the location of subclavian artery, as an anatomical landmark, can be easily identified. It is then very easy and safe to perform infraclavicular brachial plexus block. Our new method showed 89% (n = 9) successful rate. The time for the block was 4.2 +/- 1.5 min and there was an average of 3.2 +/- 0.6 needle penetrations. Thirty three percent (n = 3) had subclavian artery been punctured without formation of hematoma clinically. No patient had clinical postoperative pneumothorax.

Although suppression of thermoregulatory mechanisms during anaesthesia is generally assumed, the extent to which thermoregulation may be inactive is unknown. Twenty unpremedicated, ASA physical status class I patients (17 men and 3 women) scheduled for retinal detachment surgery were studied to evaluate the different changes of core and two skin-surface temperatures during halothane or isoflurane anaesthesia. Anaesthesia was induced by mask inhalation of halothane or isoflurane in nitrous oxide 70% and oxygen and was maintained by mechanical ventilation during surgery with halothane or isoflurane in nitrous oxide 50% and oxygen only. Core temperature (rectus) and skin-surface temperatures (forearm and fingertip) were measured during surgery using three separate thermometers (Y.S.I.: Yellow springs instrument Co., Inc. G541-211-Y01-33A0). Operating room temperatures were recorded in every case. Significant vasoconstriction was prospectively defined by a skin-surface temperature gradient between two sampling sites > or = 4 degrees C. The result indicated that there was no significant difference between core temperatures and skin-surface temperature gradients during halothane anaesthesia and isoflurane anaesthesia. However, three of the ten patients had their skin-surface temperature gradients > or = 4 degrees C in the halothane group. None of the ten patients had their skin-surface temperature gradients > or = 4 degrees C in the isoflurane group.

The effects of intravenous clonidine, a central adrenergic alpha-2 agonist, on the incidence of shivering and hemodynamic changes after epidural anesthesia were assessed in patients undergoing extracorporeal shock wave lithotripsy (ESWL). Forty ASA class I or II patients were randomly assigned in a double-blind manner to one of two groups. Twenty patients received intravenous clonidine 150 micrograms/10 ml (clonidine group) and twenty patients received normal saline (control group) at 20 min before epidural administration of 1.5% lidocaine. Shivering was determined objectively by observing involuntary muscle activity. Arterial blood pressure, heart rate, respiratory rate and oxygen saturation were measured at 5-min intervals during the first 50 minutes following IV pretreatment. There was significant difference between clonidine and control groups in the incidence of shivering (5% vs. 55%, p = 0.002). Shivering began at an average of 16.8 +/- 9 min (range: 5-30 min) in control group and only one patient shivered at 18 min in clonidine group. The mean sensory level was T7 in both groups. There were no differences between the two groups in mean arterial pressure and respiratory rate, though there was a trend in reduction of MAP in clonidine group. Heart rate and oxygen saturation decreased slightly in clonidine group. The main adverse effect of clonidine pretreatment was drowsiness. In conclusion, intravenous clonidine 150 micrograms was effective in preventing shivering with minor hemodynamic changes in patients receiving epidural anesthesia.

From December, 1990 to December, 1991, we studied the influence of PEEP and positional change to arterial blood gas in 60 ASA class II or III, aged 20 to 65 years, non-obese patients. The patients were assigned randomly into six groups. Group 1: head down position without PEEP. Group 2: head down position with PEEP 5 cmH2O. Group 3: lithotomy position without PEEP. Group 4: lithotomy position with PEEP 5 cmH2O. Group 5: supine position without PEEP. Group 6: supine position with PEEP 5 cmH2O. Blood gas analysis were performed at 5, 15, 30, 60, 120, and 180 minutes after positional change in group 1-4 and after anesthesia in group 5 and 6. The ventilator settings were: tidal volume -10 ml x 25 x (height in meters)2, rate 8/min. The results of significant difference inter-grouply were: PaO2 at 15 minutes; PaCO2 at 5 minutes; pH at 60, 120, and 180 minutes; base excess (BE) at 120 and 180 minutes. As the time progressed, PaO2 decreased in group 1, 2, and 3; PaCO2 decreased in group 3 and 5; pH decreased in group 3; BE decreased in all groups. PaCO2 were between 30-40 mmHg and no hypocarbia produced in all groups. In conclusion, ventilation of the non-obese patient based on 10 ml x 25 x (height in meters)2 x 8/min produce normocarbia and PaO2 more than 80 mmHg with 50% oxygen. No significant difference of PaO2 were found whether there were position change or PEEP 5 cmH2O.

To investigate the effects of different types of anticholinesterase on the incidence of the postoperative nausea and vomiting, 100 ASA class I-II adult premenopausal female patients undergoing elective lower abdominal surgery were randomized into two groups. In both groups, anesthesia was induced with thiopental and fentanyl and 50% nitrous oxide and 0.5-1.5% of isoflurane were used for anesthetic maintenance with succinylcholine 1 approximately 1.5 mg/kg for intubation and atracurium 0.3 mg/kg/hr for maintenance of muscle relaxation. Patients received reversal agents for neuromuscular blockade after operation when the evoked train-of-four (TOF) count returned to four visual responses. A mixture of atropine 8 micrograms/kg and edrophonium 0.75 mg/kg was given to the first group of patients while atropine 15 micrograms/kg and neostigmine 40 micrograms/kg was given to another group of patients. All the patients were observed for the occurrence of nausea or vomiting for 2 hours after the operation in the recovery room. The incidence of nausea was not statistically significantly different in both groups (20% in neostigmine group and 26% in edrophonium group). The occurrence of vomiting was also similar in both groups (8% in neostigmine group and 6% in edrophonium group). We concluded that there were no difference in the incidence of postoperative nausea or vomiting with the use of either neostigmine or edrophonium with atropine for antagonizing neuromuscular blockade after the lower abdominal surgery.

The supraclavicular brachial plexus blockade performed by palpation of the first rib as the primary landmark has been done in 60 patients in the past two years. Forty of the patients had undergone orthopedic surgery and 20 patients had soft tissue operations. Effective analgesia was achieved in 57 cases. Duration of the operations ranged from 15 to 490 min with a mean time of 130.6 min. The pain relief was long lasting that only 23 patients required additional analgesia in the post-operative period. The mean interval between completion of the operation and analgesia requirement was 11.3 h. Only 9 out of these 23 patients needed more than one doses. No complication pertaining to the technique was encountered.

Though spinal reflexes have been described in experimental brain-death animals, no documentation has been previously provided for human. The hemodynamic responses to surgical stimuli have been investigated here in eight brain-death organ donors. Baseline systolic blood pressure, diastolic blood pressure, and heart rate in observed patients were 99 +/- 15 mmHg, 61 +/- 13 mmHg, and 105 +/- 22 beats/min respectively. After skin incision, these parameters elevated maximally to 130 +/- 23 mmHg, 74 +/- 17 mmHg, and 119 +/- 18 beats/min (p < 0.05). Either spinal reflex arcs or adrenal medullary stimulation, or both, have been speculated to possibly play the role in these hemodynamic responses. However, the existence of such responses should not invalidate the diagnosis of brain death.