Practice of sedation and analgesia in German intensive care units: results of a national survey. (65/224)

INTRODUCTION: Sedation and analgesia are provided by using different agents and techniques in different countries. The goal is to achieve early spontaneous breathing and to obtain an awake and cooperative pain-free patient. It was the aim of this study to conduct a survey of the agents and techniques used for analgesia and sedation in intensive care units in Germany. METHODS: A survey was sent by mail to 261 hospitals in Germany. The anesthesiologists running the intensive care unit were asked to fill in the structured questionnaire about their use of sedation and analgesia. RESULTS: A total of 220 (84%) questionnaires were completed and returned. The RAMSAY sedation scale was used in 8% of the hospitals. A written policy was available in 21% of hospitals. For short-term sedation in most hospitals, propofol was used in combination with sufentanil or fentanyl. For long-term sedation, midazolam/fentanyl was preferred. Clonidine was a common part of up to two-thirds of the regimens. Epidural analgesia was used in up to 68%. Neuromuscular blocking agents were no longer used. CONCLUSION: In contrast to the US 'Clinical practice guidelines for the sustained use of sedatives and analgesics in the critically ill adult', our survey showed that in Germany different agents, and frequently neuroaxial techniques, were used.  (+info)

Magnitude of acute tolerance to opioids is not related to their potency. (66/224)

It was suggested that for a given analgesic effect, more potent opioids may produce smaller degrees of tolerance than those with lower analgesic potency. The use of opioids with high analgesic potency to reduce the rate of tolerance development would be an important therapeutic consideration. This study tested the hypothesis that the degree of acute tolerance to the analgesic effect of opioids is inversely related to their potency. In the experiments on rats, the analgesic effects of morphine, alfentanil, and sufentanil given by a continuous 8-h infusion at a constant rate, were determined by measuring the threshold of motor response to noxious pressure on the tail. The comparative degree of acute tolerance was determined on the basis of the decline in the level of analgesia at the end of the infusion period. Morphine 4 mg.kg-1.h-1, alfentanil 0.45 mg.kg-1.h-1, and sufentanil 0.0085 mg.kg-1.h-1 caused approximately similar increases in the pain threshold. The peak of analgesia could not be maintained; it declined by 74 +/- 6% (P less than 0.0001) with morphine, 86 +/- 6% (P less than 0.0001) with alfentanil, and 92 +/- 2% (P less than 0.0001) with sufentanil. The results indicate that the infusion of alfentanil and sufentanil, which differ from morphine by higher analgesic potency (by 10-fold and more than 100-fold, respectively), results in a decline in the degree of analgesia during infusion similar to that of morphine. These data reject the hypothesis that the magnitude of acute tolerance to the analgesic action of opioid drugs following their systemic administration is inversely related to their potency.  (+info)

Electroencephalographic quantitation of opioid effect: comparative pharmacodynamics of fentanyl and sufentanil. (67/224)

The authors compared the pharmacodynamics of sufentanil with those of fentanyl using the electroencephalogram (EEG) as a measure of opioid drug effect. Sixteen patients were given a rapid infusion of sufentanil (18.75 micrograms/min) during EEG recording. To quantitate the opioid-induced slowing of the EEG, the authors analyzed its power spectrum and calculated the spectral edge. An inhibitory sigmoid Emax model of the maximal decrease in spectral edge produced by the opioid related spectral edge values to serum concentrations of sufentanil. The resulting data for the pharmacodynamic parameters of sufentanil were compared with fentanyl parameters that were obtained by reanalysis from an identically conducted, previously published study. The half-time of blood-brain equilibration (T1/2Keo) was not statistically different between sufentanil and fentanyl (6.2 +/- 2.8 vs. 6.6 +/- 1.7 min, mean +/- SD, respectively). The intrinsic potency of sufentanil, as measured by the serum concentration needed to cause half the maximal EEG slowing (IC50), was 12-fold greater (0.68 +/- 0.31 ng/ml) than that of fentanyl (8.1 +/- 2.2 ng/ml). The second part of the study verified the hypothesis that administration of equipotent bolus doses would produce equal onset times. Bolus injections of either 125 micrograms of sufentanil or 1,250 micrograms of fentanyl were given during EEG recording. The time from injection to 50% maximal EEG slowing (T50) was calculated for each patient. The values for T50 for the two groups did not differ. The authors conclude that fentanyl and sufentanil have similar pharmacodynamic profiles, the former being 12 times more potent than the latter.  (+info)

The CSF and plasma pharmacokinetics of sufentanil after intrathecal administration. (68/224)

Eight patients (7 men and 1 woman, 45-68 yr old) scheduled to undergo thoracotomy were given, preoperatively, 15 micrograms sufentanil in the lumbar intrathecal space for a study of cerebrospinal fluid (CSF) and plasma kinetics of sufentanil. Multiple samples of plasma and CSF from the lumbar region were obtained through indwelling catheters for 12 h and analyzed for sufentanil by radioimmunoassay. Pharmacokinetic parameters were derived by noncompartmental analysis. In plasma, the maximal concentration of sufentanil appeared after 0.65 +/- 0.17 h (mean +/- SEM). No equilibrium was reached between the sufentanil concentration in CSF and plasma, but the CSF/plasma concentration ratio declined from approximately 140 at 2 h to about 15 at 10 h. Extrapolation indicates that another 10 h would be required before the concentration in CSF would equal that in plasma. The mean residence time (MRT) of sufentanil in CSF was 0.92 +/- 0.08 h and in plasma was 6.8 +/- 0.6 h. The volume of distribution at steady state (Vss) in the subarachnoid compartment was 1.54 +/- 0.39 ml/kg, and the clearance from the CSF was 27 +/- 5 microliters.kg-1.min-1. The intrathecal administration of 15 micrograms sufentanil at the beginning of the operation did not produce analgesia that lasted into the postoperative period. Most patients had urinary retention, but none experienced any serious complications. This study demonstrates that the lipophilic opioid sufentanil undergoes rapid clearance from CSF and absorption to plasma after intrathecal administration. These pharmacokinetic characteristics are slower for the less lipophilic opioids meperidine and morphine. The rapid pharmacokinetics of sufentanil explain its rapid onset of action and short-lasting effects.  (+info)

The effect of epidural sufentanil in ropivacaine on urinary retention in patients undergoing gastrectomy. (69/224)

BACKGROUND: Although epidural opioids have excellent analgesic property, their side-effects limit its use in patient-controlled epidural analgesia (PCEA). This study was designed to compare side-effects of epidural sufentanil in ropivacaine with that of morphine in ropivacaine focusing on lower urinary tract function after major abdominal surgery. METHODS: In total 60 patients undergoing gastrectomy were randomly allocated to receive either sufentanil in ropivacaine (Group S, n=30) or morphine in ropivacaine (Group M, n=30) for their PCEA. Epidural catheter was inserted between the 7th and 8th thoracic spine. Visual analogue pain score and side-effects such as nausea, vomiting, pruritus, hypotension and urinary retention were evaluated during postoperative days (PODs) 1 and 2 in the postanaesthetic care unit. RESULTS: The incidence of serious to major micturition problem in Group S was lower than that in Group M (P<0.001). The incidence of pruritus, nausea and vomiting was also lower in Group S than in Group M on POD 1. CONCLUSIONS: The lower incidence of major/serious micturition problem in patients receiving sufentanil in ropivacaine thoracic epidural analgesia suggests that continuation of urinary drainage may not be necessary from POD 1 onwards.  (+info)

Microcirculatory alterations induced by sedation in intensive care patients. Effects of midazolam alone and in association with sufentanil. (70/224)

INTRODUCTION: Sedation is widely used in intensive care unit (ICU) patients to limit the risk of pulmonary barotrauma and to decrease oxygen needs. However, adverse effects of cc5128sedation have not been fully evaluated; in particular, effects of benzodiazepine and opiates on microcirculation have not been extensively studied. The aim of this study was to evaluate the microcirculatory effects of a sedation protocol commonly prescribed in the ICU. METHODS: Ten non-septic patients under controlled ventilation requiring sedation for therapeutic purposes were enrolled in a prospective observational study conducted in an ICU of a university hospital. Sedation was conducted in two successive steps: first, each patient received midazolam (0.1 mg/kg per hour after a bolus of 0.05 mg/kg, then adapted to reach a Ramsay score of between 3 and 5). Second, after one hour, sufentanil was added (0.1 microg/kg per hour after a bolus of 0.1 microg/kg). Arterial pressure, heart rate, cardiac output determined by transthoracic impedance, transcutaneous oxygen (tcPO2) and carbon dioxide (tcPCO2) pressures, and microcirculatory blood flow determined by laser Doppler flowmetry at rest and during a reactive hyperaemia challenge were measured before sedation (NS period), one hour after midazolam infusion (H period), and one hour after midazolam-sufentanil infusion (HS period). RESULTS: Arterial pressure decreased in both sedation periods, but heart rate, cardiac output, tcPO2, and tcPCO2 remained unchanged. In both sedation periods, microcirculatory changes occurred with an increase in cutaneous blood flow at rest (H period: 207 +/- 25 perfusion units [PU] and HS period: 205 +/- 25 PU versus NS period: 150 +/- 22 PU, p < 0.05), decreased response to ischaemia (variation of blood flow to peak: H period: 97 +/- 16 PU and HS period: 73 +/- 9 PU versus NS period: 141 +/- 14 PU, p < 0.05), and attenuation of vasomotion. CONCLUSION: Sedation with midazolam or a combination of midazolam and sufentanil induces a deterioration of vasomotion and microvascular response to ischaemia, raising the question of whether this effect may further alter tissue perfusion when already compromised, as in septic patients.  (+info)

Intravenous lidocaine infusion facilitates acute rehabilitation after laparoscopic colectomy. (71/224)

BACKGROUND: Intravenous infusion of lidocaine decreases postoperative pain and speeds the return of bowel function. The authors therefore tested the hypothesis that perioperative lidocaine infusion facilitates acute rehabilitation protocol in patients undergoing laparoscopic colectomy. METHODS: Forty patients scheduled to undergo laparoscopic colectomy were randomly allocated to receive intravenous lidocaine (bolus injection of 1.5 mg/kg lidocaine at induction of anesthesia, then a continuous infusion of 2 mg.kg.h intraoperatively and 1.33 mg.kg.h for 24 h postoperatively) or an equal volume of saline. All patients received similar intensive postoperative rehabilitation. Postoperative pain scores, opioid consumption, and fatigue scores were measured. Times to first flatus, defecation, and hospital discharge were recorded. Postoperative endocrine (cortisol and catecholamines) and metabolic (leukocytes, C-reactive protein, and glucose) responses were measured for 48 h. Data (presented as median [25-75% interquartile range], lidocaine vs. saline groups) were analyzed using Mann-Whitney tests. P<0.05 was considered statistically significant. RESULTS: Patient demographics were similar in the two groups. Times to first flatus (17 [11-24] vs. 28 [25-33] h; P<0.001), defecation (28 [24-37] vs. 51 [41-70] h; P=0.001), and hospital discharge (2 [2-3] vs. 3 [3-4] days; P=0.001) were significantly shorter in patients who received lidocaine. Lidocaine significantly reduced opioid consumption (8 [5-18] vs. 22 [14-36] mg; P=0.005) and postoperative pain and fatigue scores. In contrast, endocrine and metabolic responses were similar in the two groups. CONCLUSIONS: Intravenous lidocaine improves postoperative analgesia, fatigue, and bowel function after laparoscopic colectomy. These benefits are associated with a significant reduction in hospital stay.  (+info)

Determination of the full dose-response relation of intrathecal bupivacaine, levobupivacaine, and ropivacaine, combined with sufentanil, for labor analgesia. (72/224)

BACKGROUND: Ropivacaine and levobupivacaine are local anesthetics that produce less motor block and greater sensory-motor separation when compared with equal milligram doses of bupivacaine. Although minimum local analgesic concentration studies suggested that they are less potent than bupivacaine, full dose-response studies have not been performed. The current trial describes the dose-response relation of levobupivacaine, ropivacaine, and bupivacaine, combined with sufentanil, when used for intrathecal labor analgesia. METHODS: Four hundred fifty term parturients in active labor were included in this double-blind, randomized trial. Combined spinal-epidural anesthesia was performed, and ropivacaine, levobupivacaine, or bupivacaine was intrathecally administered in a dose of 1.0, 1.5, 2.0, 2.5, 3.0, or 3.5 mg, always combined with 1.5 microg sufentanil. Patients were considered responders to spinal analgesia if the visual analog scale score for pain was less than 25 mm within 15 min and the visual analog scale score remained less than 25 mm for 45 min. Patient demographics, obstetric data, maternal side effects, and fetal and neonatal well-being were noted. Group-specific dose-response curves were constructed using a probit regression model. RESULTS: The ED95 of bupivacaine was 3.3 mg (95% confidence interval, 2.9-4.1). The ED95s of ropivacaine and levobupivacaine were 4.8 mg (95% confidence interval, 4.0-6.7) and 5.0 mg (95% confidence interval, 4.1-7.0), respectively. Racemic bupivacaine was significantly more potent than ropivacaine (P=0.0027) and levobupivacaine (P=0.0006). Ropivacaine and levobupivacaine were of similar potency (P=0.91). CONCLUSIONS: This full dose-response study suggests that ropivacaine and levobupivacaine are of similar potency, whereas bupivacaine is more potent than both other drugs.  (+info)