Anesthesia and analgesia
-
Anesthesia and analgesia · May 1997
Duration of intrathecal labor analgesia: early versus advanced labor.
Early first-stage labor pain is primarily visceral in origin. Increasing pain intensity and transition to somatic nociceptive input characterizes late first- and second-stage labor pain. The effect of this change in nociceptive input on the duration of intrathecal labor analgesia has not been well studied. ⋯ Duration of analgesia was defined as the lesser of time until the pain score exceeded 5 or until a request for supplemental epidural analgesia was made. The duration of spinal analgesia was significantly less when intrathecal injection was made in advanced labor (120 +/- 26 min) compared with early labor (163 +/- 57 min, P < 0.01). We conclude that cervical dilation and stage of labor significantly impact the effective duration of intrathecal sufentanil/ bupivacaine labor analgesia.
-
Anesthesia and analgesia · May 1997
Neurologic complications of 603 consecutive continuous spinal anesthetics using macrocatheter and microcatheter techniques. Perioperative Outcomes Group.
Recent case reports of cauda equina syndrome after continuous spinal anesthesia have led to a reevaluation of the indications and applications of this regional anesthetic technique. However, few large studies have formally investigated the frequency of neurologic complications using macro- and microcatheter (smaller than 24 gauge) techniques. This retrospective review examines 603 continuous spinal anesthetics, including 127 administered through a 28-gauge microcatheter, performed between June 1987 and May 1992. ⋯ An epidural blood patch was performed in 41 (6.8%) patients. The frequency of neurologic complications, excluding PDPH, is similar to those in published reviews. However, PDPH in microcatheter patients is more frequent than previously reported.
-
Anesthesia and analgesia · May 1997
Respiratory mechanics, gastric insufflation pressure, and air leakage of the laryngeal mask airway.
A potential risk of the laryngeal mask airway (LMA) is incomplete mask seal, which causes air leakage or insufflation of air into the stomach. The objective of the present study was to assess respiratory mechanics, quantify air leakage, and measure gastric air insufflation in patients ventilated via the LMA. Thirty patients were studied after induction of anesthesia but prior to any surgical manipulations. ⋯ The end point of 40 cm H2O airway pressure was reached in only three patients. We conclude that the LMA is not better in preventing airway pressure transmission to the esophagus than a conventional face mask. However, a high FL is associated with reduced gastric air insufflation.
-
Anesthesia and analgesia · May 1997
Prevention of fetal and maternal cyanide toxicity from nitroprusside with coinfusion of sodium thiosulfate in gravid ewes.
Coadministration of sodium thiosulfate with sodium nitroprusside (SNP) to children and adults prevents increases in cyanide concentrations during anesthesia or long-term SNP infusions. We wondered whether maternally administered sodium thiosulfate would prevent increases in fetal red cell cyanide concentrations in gravid ewes receiving SNP infusions. Under anesthesia, the fetal head was delivered through a lateral hysterotomy for catheterization of the jugular vein; the fetus was left in utero. ⋯ An additional control ewe and fetus died from apparent cyanide poisoning late during the course of the experiment. While control ewes and fetuses suffered progressive increases in red cell cyanide concentrations into the toxic range, experimental ewes and fetuses never developed toxic red cell cyanide levels (ewes P < .003, fetuses P < .004). These data, if applicable to humans, suggest that coadministration of sodium thiosulfate with SNP to pregnant women at doses currently in use for nonpregnant patients will prevent fetal, as well as maternal, cyanide toxicity.
-
Anesthesia and analgesia · May 1997
ONO-5046, an elastase inhibitor, attenuates endotoxin-induced acute lung injury in rabbits.
Endotoxin causes acute lung injury resembling acute respiratory distress syndrome. Elastase, as well as reactive oxygen species released from activated neutrophils, are thought to play pivotal roles in the pathogenesis of this lung injury. This study investigated whether ONO-5046, a specific elastase inhibitor, can attenuate acute lung injury induced by endotoxin in rabbits. ⋯ Endotoxin caused extensive morphologic lung damage, which was lessened by ONO-5046. In conclusion, intravenous ONO-5046 pretreatment attenuated endotoxin-induced lung injury in rabbits. This beneficial effect of ONO-5046 may be due, in part, to a reduction in the levels of mediators that activate neutrophils, in addition to the direct inhibitory effect on elastase.