Anesthesia and analgesia
-
Anesthesia and analgesia · Jun 1997
Clinical TrialDisplacement of the double-lumen endobronchial tube can be detected by bronchial cuff pressure change.
We measured the bronchial cuff pressure of left-sided double-lumen endobronchial tubes (DLTs) in 54 patients to confirm the effect of DLT displacement on cuff pressure. After positioning the cephalad surface of the bronchial cuff of the DLT 2.5 cm distal to the carina (23 patients in the first part of the study) or just below the carina (23 patients in the second part), the cuff was withdrawn in 0.5-cm steps during right-sided, one-lung ventilation. The bronchial cuff pressure was measured, and the capnogram and pressure-volume loop, displayed by a side-stream spirometer, was evaluated. ⋯ The bronchial cuff pressure decreased significantly by 28.4 cm H2O (P < 0.01) and 21.3 cm H2O (P < 0.01) in the first and second parts, respectively, before the pressure-volume loop or the capnogram changed. The bronchial cuff pressure in the third part showed no significant change. We conclude that bronchial cuff pressure monitoring was very helpful in detecting displacement of the DLT during right-sided, one-lung ventilation.
-
Anesthesia and analgesia · Jun 1997
Cerebral hemoglobin and optical pathlength influence near-infrared spectroscopy measurement of cerebral oxygen saturation.
Near-infrared spectroscopy (NIRS) is a noninvasive optical technique to monitor cerebral oxygen saturation at the bedside. Despite its applicability, NIRS has had limited clinical use because of concerns about accuracy, noted by intersubject variability in slope and intercept of the line between NIRS- and weighted-average arterial-cerebrovenous saturation (SMO2). This study evaluated transcranial optical pathlength and cerebral hemoglobin concentration as sources for this intersubject variability. ⋯ By adjusting the NIRS algorithm with the cerebral hemoglobin measurements, slope and intercept remained unchanged by hemodilution. These data indicate that intersubject variability in NIRS originates, in part, from biologic variations in transcranial optical pathlength and cerebral hemoglobin concentration. Instruments to account for these factors may improve NIRS cerebral oxygen saturation measurements.
-
Anesthesia and analgesia · Jun 1997
Randomized Controlled Trial Comparative Study Clinical TrialThe effect of skull-pin insertion on cerebrospinal fluid pressure and cerebral perfusion pressure: influence of sufentanil and fentanyl.
This randomized prospective study measured the effects of an intravenous opioid bolus on cerebrospinal fluid pressure (CSFP), mean arterial pressure (MAP), and cerebral perfusion pressure (CPP) during skull-pin insertion. Twenty-two adult patients scheduled for elective craniotomy for supratentorial lesions were studied. Outcome variables were MAP, heart rate (HR), and lumbar CSFP. ⋯ In the sufentanil group, HR decreased approximately 10 bpm after opioid injection and remained decreased throughout the study. In fentanyl-treated patients, HR decreased 8 bpm after opioid injection but returned to preopioid rates after skull-pin insertion. In conclusion, in anesthetized patients, an intravenous bolus of fentanyl or sufentanil prior to skull-pin insertion results in stable values of CSFP, CPP, BP, and HR when the hemodynamic effects of the opioid are modified with phenylephrine and atropine.
-
Anesthesia and analgesia · Jun 1997
Randomized Controlled Trial Clinical TrialIntraarticular morphine analgesia in chronic pain patients with osteoarthritis.
Controlled clinical studies have shown that local administration of morphine can significantly relieve acute postoperative pain. This analgesic effect is long-lasting (up to 48 h) and is mediated by peripheral opioid receptors. Experimental evidence shows that analgesic effects of peripheral opioids and the density of opioid receptors on peripheral sensory nerves increase with the duration of painful inflammatory processes. ⋯ The analgesic effect was surprisingly long-lasting and extended into Phase II, a carry-over effect that prevented the analysis of Phase II. No side effects were reported. The treatment of arthritic pain by peripherally acting opioids may be a promising alternative to currently available medications that have serious side effects.
-
Anesthesia and analgesia · Jun 1997
Randomized Controlled Trial Clinical TrialDetermination of the dose-response relationship for intrathecal sufentanil in laboring patients.
Multiple studies have investigated the efficacy of intrathecal opioids, particularly sufentanil, in laboring parturients. However, until the important pharmacological indices of the 50% and 95% effective doses (ED50 and ED95, respectively) are defined, reliable comparative studies among drugs at equipotent doses cannot be performed. This study was performed to establish the dose-response relationship of intrathecal sufentanil analgesia in labor. ⋯ Assisted delivery and cesarean section rates were similar for all groups. Intrathecal sufentanil provides rapid onset of analgesia for labor. The ED50 and ED95 values established in this study should help to provide benchmarks both for the safe clinical use of intrathecal sufentanil for labor and for future comparison studies with other intrathecal analgesic techniques.