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J A Stirt

Publications and source records attributed to J A Stirt.

10 recordsLinked to original sources

Intraocular pressure during rapid sequence induction: use of moderate-dose sufentanil or fentanyl and vecuronium or atracurium.

We studied the effect of rapid sequence induction of anaesthesia on intraocular pressure in physically fit, ASA class I or II patients using combinations of sufentanil (1 microgram/kg), or fentanyl (5 micrograms/kg) and vecuronium (0.2 mg/kg) or atracurium (1.0 mg/kg). All patients received thiopentone (5 mg/kg), following which those in group 1 received sufentanil and vecuronium, group 2 sufentanil and atracurium, group 3 fentanyl and vecuronium, and group 4 fentanyl and atracurium. Laryngoscopy and intubation were performed 60 seconds after induction. Intraocular pressure was measured prior to induction, 30 and 60 seconds after induction, immediately after intubation, and postintubation for 5 minutes. Postinduction and postintubation intraocular pressure values in all four groups did not exceed baseline values. We conclude that in fit patients, the combination of thiopentone, moderate dose narcotics, and an appropriate dose of vecuronium or atracurium produces satisfactory conditions for intubation following rapid sequence induction without increases in intraocular pressure. This technique should not, however, be employed when multiple other injuries are present, along with an open eye.

Adult

Accelerated recovery from combined atracurium-vecuronium neuromuscular block.

Patients given combinations of non-depolarizing neuromuscular blocking drugs have been reported to recover from neuromuscular block more rapidly than patients given a single drug. This study was designed to assess if this phenomenon occurred with the combination of atracurium and vecuronium. During nitrous oxide-fentanyl anaesthesia, 30 adult patients were allocated randomly to receive atracurium 0.5 mg kg-1, vecuronium 0.1 mg kg-1, or a combination of atracurium 0.125 mg kg-1 + vecuronium 0.025 mg kg-1. All patients had 100% neuromuscular block, and times to block onset did not differ significantly between the three groups. Recovery to 10, 25, 50 and 90% of control twitch height was significantly faster in the group receiving the combination of drugs.

Adult

Increases in intracranial pressure from succinylcholine: prevention by prior nondepolarizing blockade.

Whether succinylcholine causes an increase in intracranial pressure (ICP) in patients with brain lesions is uncertain and, if increased ICP does occur, its pathophysiology remains unknown. The authors investigated both the effect of succinylcholine on ICP and its modification with prior neuromuscular blockade by measuring ICP (subarachnoid bolt) in 13 consecutive patients with brain tumors who received succinylcholine both before and after complete neuromuscular blockade with vecuronium. Anesthesia was induced with thiopental, 6 mg X kg-1 iv, and nitrous oxide, 70% in oxygen, while ventilation was controlled (PaCO2 = 37.2 mmHg +/- 1.7 SE). Succinylcholine, 1 mg X kg-1 iv, was administered and ICP, heart rate (HR), and blood pressure (BP) were recorded until normal twitch tension was restored. Complete neuromuscular blockade was then established with vecuronium, 0.14 mg X kg-1 iv; 3 min later, succinylcholine, 1 mg X kg-1 iv, was repeated. The resulting changes in ICP, HR, and BP were recorded for 3 min. Following the first dose of succinylcholine, mean ICP increased from 15.2 mmHg +/- 1.3 SE to 20.1 mmHg +/- 2.0 SE (P less than 0.05), with five of the patients sustaining increases in ICP of 9 mmHg or greater. In contrast, when succinylcholine was given after vecuronium-induced paralysis, no patient developed an increase in ICP greater than 3 mmHg (P less than 0.05 compared with the incidence of ICP greater than or equal to 9 mmHg observed after the first dose of succinylcholine). A second group of six patients received two doses of succinylcholine according to the same protocol but without an intervening dose of vecuronium.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Atracurium, vecuronium, and intraocular pressure in humans.

We studied 60 nonophthalmologic patients, allocated to six treatment groups, to assess the effects of atracurium and vecuronium on intraocular pressure (IOP). All patients had IOP measured while awake, using pneumotonometry. In group 1, anesthesia was induced with thiopental, 5 mg/kg, and maintained with N2O, 70% in O2, using controlled mask ventilation, for 5 min. These patients then received atracurium, 0.5 mg/kg. After 5 additional minutes of ventilation, the trachea was intubated. From 1 min after thiopental administration until 1 min after intubation, IOP was recorded every minute. Patients in groups 2, 3, and 4 were treated identically to those in group 1, except the muscle relaxant given was atracurium, 1.0 mg/kg, vecuronium, 0.1 mg/kg, or vecuronium, 0.2 mg/kg, respectively. Patients in groups 5 and 6 underwent rapid sequence induction with thiopental, 5 mg/kg, and atracurium, 1.0 mg/kg, or vecuronium, 0.2 mg/kg, respectively. IOP was measured 1 min later, followed by intubation and IOP measurements for the next 3 min. Intraocular pressure decreased significantly in groups 1, 2, 4, and 6 after thiopental and remained stable in all groups during ventilation with N2O. Neither atracurium nor vecuronium affected IOP, nor was there any correlation between IOP and degree of neuromuscular blockade. However, IOP increased significantly after intubation in all six groups. We conclude that atracurium or vecuronium alone has no adverse effects on IOP.

Adult

Intracranial pressure after atracurium in neurosurgical patients.

In order to investigate the usefulness of atracurium for neurosurgical anesthesia, we studied its impact on intracranial pressure (subarachnoid bolt) mean arterial pressure (radial artery catheter) and cerebral perfusion pressure (mean arterial pressure-intracranial pressure) in 20 patients undergoing elective craniotomy for brain tumor excision. General anesthesia was induced with thiopental, 4 mg/kg intravenously, and maintained with 70 percent nitrous oxide in oxygen. Ventilation was controlled by face mask, with end-tidal CO2 held constant. Once intracranial pressure and mean arterial pressure had stabilized, the response to atracurium, 0.5 mg/kg intravenously, was continuously recorded for 5 min in 10 patients. An additional 10 patients received no atracurium and served as matched controls. Thiopental caused reductions in ICP in both groups of patients. Comparing the responses of the patients who received atracurium with those who did not, we found that atracurium had no significant effect on intracranial pressure, mean arterial pressure or cerebral perfusion pressure. Based on these data we conclude that atracurium appears to be preferable to the other available neuromuscular blocking agents that have been evaluated for neurosurgical anesthesia.

Adult