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H Breivik

Publications and source records attributed to H Breivik.

At least 37 records · Page 2Linked to original sources
PubMed1999

The safety and effectiveness of remifentanil as an adjunct sedative for regional anesthesia.

UNLABELLED: We assessed the sedative potential of continuous infusions of remifentanil with a validated composite alertness scale in 160 patients (ASA physical status I or II) undergoing hip replacement surgery with spinal block (n = 61) or hand surgery using brachial plexus block (n = 93). They were randomized to receive one of the following initial dose regimens in double-blinded fashion: placebo or 0.04, 0.07, or 0.1 microg x kg(-1) x min(-1) remifentanil subsequently titrated to effect. Additional midazolam IV was allowed for adequate sedation as required. The combined analysis of both surgery groups revealed a dose-related increase in achievement of sedation level > or =2 within 15 min of the start of the study drug infusion; all remifentanil dose comparisons with placebo reached significance (P < 0.001). The remifentanil 50% effective dose for a composite sedation level > or =2 within 15 min of the start of drug infusion was estimated as 0.043 microg x kg(-1) x min(-1) (95% confidence interval 0.01, 0.059). The requirement for midazolam decreased with increasing remifentanil dose compared with placebo (P < 0.001). The median time to return to alertness after the end of infusion was 10-12 min in the remifentanil groups and 5 min in the placebo group. Significant incidences of nausea, pruritus, sweating, and respiratory depression were reported during remifentanil infusions compared with placebo. The data suggest that remifentanil may be useful for supplementation of regional anesthesia, provided that ventilation is carefully monitored. IMPLICATIONS: In this dose-finding, placebo-controlled study, remifentanil infusions were used to provide sedation during spinal and brachial plexus regional anesthesia. The 50% effective dose for achievement of sedation was 0.043 microg x kg(-1) x min(-1). Return to alertness occurred after 10-12 min (median time). Remifentanil infusions can be used to supplement regional anesthesia, but this requires careful monitoring of ventilation.

Adjuvants, Anesthesia↗
PubMed1999

Magnetic resonance imaging demonstrates lack of precision in needle placement by the infraclavicular brachial plexus block described by Raj et al.

UNLABELLED: The infraclavicular brachial plexus block first described by Raj et al. was supposed to anesthetize all the main peripheral nerves of the brachial plexus without the risk of pneumothorax. However, in performing the block, we have had difficulties finding the nerves at the cord level. Therefore, we questioned whether the recommended needle direction (the "Raj line") guides the needle close enough to the cords. We therefore designed an anatomic study to answer this question and to assess the risks of entering the pleura and axillary vein. Ten volunteers were examined noninvasively in an open model magnetic resonance scanner. The Raj line deviated greatly from a defined location on the cords by a mean of 26 (range 14-39) mm, always caudad, and posterior to the target in nine cases. Further, the needle trajectory's shortest distance to the pleura was only 10 (0-27) mm, and in one case, it hit the pleura. Finally, the Raj line's distance to the axillary vein was also short, 11 (0-18) mm. We conclude that a modification of the method is necessary to guide the needle closer to the cords and further away from the pleura and the axillary vein. A more lateral needle insertion seems beneficial. IMPLICATIONS: Using a magnetic resonance scanner, the anatomical basis of Raj's infraclavicular method for brachial plexus blockade was examined in volunteers. The results show that the method should be modified to make it more precise and to provide less risk of complications.

Adult↗
PubMed1999

Infectious complications of epidural anaesthesia and analgesia.

Clinically overt infections of the epidural catheter skin entry site occur in approximately 5% of patients after a few days; deep catheter tract infections occur in approximately 5% of patients after more prolonged epidural analgesia. This indicates that potentially serious epidural infectious complications are ever-present risks of epidural anaesthesia and analgesia. This review focuses on risk factors and guidelines for routine epidural analgesia that may minimize the risks of serious infectious complications.

Journal Article↗
PubMed1999

Epidural and spinal anaesthesia and the use of anticoagulants.

Neurological injuries after epidural/spinal analgesia are a serious but uncommon problem. Spinal haematoma cause a proportion of these complications, and can be minimized by avoiding central nervous blockade in high-risk patients, especially those receiving anticoagulant therapy. Early recognition of spinal haematoma by basic neurological monitoring allows early intervention and improves outcome.

Anesthesia, Epidural↗
PubMed1998

[Complications during and after surgery and childbirth where spinal or epidural analgesia is used. Guidelines for safe practice].

When complications and neurological sequelae occur during a spinal or epidural anaesthetic the causes are clearly related to the procedures in the following cases: severe haemodynamic or respiratory derangement, documented needle trauma of nerve fibres, intraspinal haematoma in anticoagulated or heparinized patients, and epidural infection where an infected epidural catheter entry site is documented. A number of well documented cases have been published in which surgery or patient-related pathology were primary causes of "typical" spinal or epidural neurological complications. These emphasize the importance of searching for other risk factors of neurological sequelae after surgery or child birth in cases where there is no obvious deviation from the normal epidural or spinal procedures. Increased focus on the infrequent, but serious complications of these essentially very safe techniques for surgical anaesthesia and pain relief should serve to increase our vigilance, but should not reduce the application of spinal and epidural analgesia. Guidelines are offered for the effective and safe practice of spinal and epidural anaesthesia and pain relief: adequate supervision of trainee anaesthetists, vigilant monitoring for early detection and handling of complications, and trained nurses on surgical wards to monitor and handle patients during epidural analgesia are important. Sufficient readiness for urgent handling of the very rare, but devastating complications of intraspinal bleeding or infection is an absolute necessity.

Analgesia, Epidural↗
PubMed1998

Postoperative pain management: why is it difficult to show that it improves outcome?

Intuitively it seems obvious that unrelieved, severe acute pain after surgery may have a number of undesirable effects [1]. Many experienced clinicians maintain that the immediate postoperative course as well as long-term outcome may be influenced by the quality of pain relief after surgery or trauma [1, 2]. However, there are conflicting data from published clinical studies concerning the beneficial effects of postoperative pain management on short-term and long-term outcome of surgery [3].

Acute Disease↗
PubMed1998

Adrenaline markedly improves thoracic epidural analgesia produced by a low-dose infusion of bupivacaine, fentanyl and adrenaline after major surgery. A randomised, double-blind, cross-over study with and without adrenaline.

BACKGROUND: Basic pharmacological research indicates that there are synergistic antinociceptive effects at the spinal cord level between adrenaline, fentanyl and bupivacaine. Our clinical experience with such a mixture in a thoracic epidural infusion after major surgery confirms this. The objectives of the present study were to evaluate the effects on postoperative pain intensity, pain relief and side effects when removing adrenaline from this triple epidural mixture. METHODS: A prospective, randomised, double-blind, cross-over study was carried out in 24 patients after major thoracic or abdominal surgery. Patients with only mild pain when coughing during a titrated thoracic epidural infusion of about 10 ml.h-1 of bupivacaine 1 mg.ml-1, fentanyl 2 micrograms.ml-1, and adrenaline 2 micrograms.ml-1 were included. On the 1st and 2nd postoperative days each patient was given a double-blind epidural infusion, at the same rate, with or without adrenaline. The effect was observed for 4 h or until pain when coughing became unacceptable in spite of a rescue analgesic procedure. Rescue analgesia consisted of up to two epidural bolus injections per hour and i.v. morphine if necessary. All patients received rectal paracetamol 1 g, every 8 h. Fentanyl serum concentrations were measured with a radioimmunoassay technique at the start and end of each study period. Main outcome measures were extent of sensory blockade and pain intensity at rest and when coughing, evaluated by a visual analogue scale, a verbal categorical rating scale, the Prince Henry Hospital pain score, and an overall quality of pain relief score. RESULTS: The number of hypaesthetic dermatomal segments decreased (P < 0.001) and pain intensity at rest and when coughing increased (P < 0.001) when adrenaline was omitted from the triple epidural mixture. This change started within the first hour after removing adrenaline. After 3 h pain intensity when coughing had increased to unacceptable levels in spite of rescue analgesia (epidural bolus injections and i.v. morphine). Within 15-20 min after restarting the triple epidural mixture with adrenaline, pain intensity was again reduced to mild pain when coughing. Serum concentration of fentanyl doubled from 0.22 to 0.45 ng.ml-1 (P < 0.01), and there was more sedation during the period without adrenaline. CONCLUSIONS: Adrenaline increases sensory block and improves the pain-relieving effect of a mixture of bupivacaine and fentanyl infused epidurally at a thoracic level after major thoracic or abdominal surgery. Serum fentanyl concentrations doubled and sedation increased when adrenaline was removed from the epidural infusion, indicating more rapid vascular absorption and systemic effects of fentanyl.

Adrenergic alpha-Agonists↗
PubMed1998

Remifentanil.

Explore the source record for details and available documents.

Analgesics, Opioid↗
PubMed1997

A comparison of remifentanil and alfentanil in patients undergoing major abdominal surgery.

The efficacy and safety of remifentanil and alfentanil for patients undergoing major abdominal surgery were compared. Premedicated patients received a loading dose of remifentanil (1.0 microgram.kg-1; n = 116) and a continuous infusion of 0.5 microgram.kg-1.min-1, or a loading dose of alfentanil (25 micrograms.kg-1; n = 118) and a continuous infusion of 1.0 microgram.kg-1.min-1. Propofol was administered (10 mg every 10 s) until loss of consciousness. Patients' lungs were ventilated with 66% nitrous oxide and 0.5% (end-tidal) isoflurane in oxygen. The study drug infusion rate was reduced by 50% 5 min after intubation. Alfentanil was discontinued 15 min before the end of surgery, whereas remifentanil was continued in the immediate postoperative period at a reduced dose. Responses to intubation (28%) and skin incision (17%) occurred approximately twice as often in the alfentanil group (15% and 8%; p = 0.014 and p = 0.037, respectively). More patients receiving alfentanil had one or more responses to surgery (72% vs. 57%; p = 0.016). The time to spontaneous respiration, adequate respiration, response to verbal command and time to recovery room discharge were similar. However, owing to decreased variability, the time to extubation was shorter with remifentanil than with alfentanil (p = 0.048). There was a similar overall incidence of adverse events in both groups, 82% and 75% of patients, respectively. Adverse events associated with remifentanil were rapidly controlled by dose reductions. The incidence of intra-operative hypotension and bradycardia was higher in the remifentanil group (p < or = 0.033). An initial remifentanil infusion rate of 0.1 microgram.kg-1.min-1 titrated to individual need provided postoperative pain relief in the presence of adequate respiration in 71% of patients. When using remifentanil in the immediate postoperative setting, rapid administration of bolus doses and infusion rate increases resulted in a relatively high incidence of muscle rigidity, respiratory depression and apnoea. Changing the postoperative regimen to avoid rapid changes in remifentanil blood concentration resulted in more effective analgesia and dramatically reduced the incidence of adverse events during this period. In patients undergoing major abdominal surgery, remifentanil appears to offer superior intra-operative haemodynamic stability during stressful surgical events compared with alfentanil without compromising recovery from anaesthesia. Remifentanil can be administered as a postoperative analgesic agent at a starting dose of 0.1 microgram-.kg-1.min-1; however, it should only be used in the presence of adequate supervision and monitoring of the patient. Administration of bolus doses is not recommended in this setting.

Abdomen↗
PubMed1997

Mapping of punctuate hyperalgesia around a surgical incision demonstrates that ketamine is a powerful suppressor of central sensitization to pain following surgery.

BACKGROUND: Tissue injury induces central sensitization in the spinal cord dorsal horn neurons via mechanisms involving N-methyl-D-aspartate (NMDA) receptors, leading to secondary hyperalgesia. Using punctuate mechanical hyperalgesia as a measure of central sensitization, we examined whether induction and maintenance of central sensitization after surgery could be prevented by a low-dose infusion of the NMDA-receptor antagonist ketamine. METHODS: Twenty living kidney donors were included in a randomized, double-blind, parallel, two-group study. Before start of surgery 10 patients received an i.v. bolus of racemic ketamine 0.5 mg.kg-1, followed by a continuous i.v. infusion of ketamine 2 micrograms.kg-1.min-1 for 24 h, thereafter 1 microgram.kg-1.min-1 for another 48 h. The control group received placebo bolus and infusion. A standard general anaesthesia including fentanyl was used. Patient-controlled (PCA) i.v. morphine was used for postoperative analgesia. Punctuate mechanical hyperalgesia and temporal summation of mechanical stimuli causing "wind-up pain" were measured using von Frey filaments. RESULTS: The area of punctuate mechanical hyperalgesia was significantly reduced in the ketamine group 1, 3 and 7 d after the operation (P < 0.01-0.001). "Wind-up pain" was also reduced by ketamine (P < 0.05). PCA morphine consumption and pain intensity (visual analogue scale) differed between groups only during the first hours after surgery, in favour of ketamine. The ketamine patients scored significantly higher on a global satisfaction score. Side-effects were most frequent in the placebo group. CONCLUSION: Low-dose i.v. infusion of ketamine during and after surgery reduces mechanical punctuate hyperalgesia surrounding the surgical incision. These results indicate that blockade of NMDA receptors prevents the central sensitization caused by nociceptive input during and after surgery.

Adult↗
PubMed1996

Additive analgesic effect of codeine and paracetamol can be detected in strong, but not moderate, pain after Caesarean section. Baseline pain-intensity is a determinant of assay-sensitivity in a postoperative analgesic trial.

BACKGROUND: A randomized, double-blind, placebo-controlled single oral dose study was done in order to examine whether codeine has an additive analgesic effect to that of paracetamol for moderate and strong postoperative pain after abdominal surgery. The maximum recommended single dose of paracetamol 1000 mg (Paracet) was compared with a combination of a submaximal dose of paracetamol 800 mg plus codeine 60 mg (Paralgin forte) and placebo for pain relief after Caesarean section in 125 patients. METHODS: Visual analogue pain intensity score (VAS 0-100 mm) and categorical pain relief score were recorded for 6 hours after the study drug intake. The main efficacy variables analyzed were: pain intensity difference and summed pain intensity differences during the first 3 and 6 h after study drug intake, total pain relief during the first 3 and 6 h, global evaluation score at the end of the observation period, and time to rescue analgesic. RESULTS: Because of protocol violations, 17 patients were excluded from the analysis of effects. Among the 108 patients included in the analysis of analgesic effect, 49 patients had moderate baseline pain (VAS between 40 and 60 mm on a 100 mm scale), and 59 patients had strong baseline pain (VAS more than 60 mm). In patients with strong baseline pain, statistically highly significant differences were documented in efficacy variables between the active drugs and placebo and between the two active drugs. However, in patients with moderate baseline pain, no differences were found between the study drugs in any of the analgesic efficacy variables. CONCLUSION: This study thus confirms that codeine has additive analgesic effect to paracetamol in pain after surgery. Our results show the importance of initial pain intensity in postoperative assessment of analgesic drugs. Assay-sensitivity and test power are increased by selecting patients with sufficiently high initial pain intensity and by comparing groups of patients with identical surgery and similar demographic variables.

Acetaminophen↗
PubMed1996

Perianaesthetic management of patients with endocrine disease.

Hyper- or hypofunctioning endocrine organs present a number of perianaesthetic challenges. This review covers some of the issues of perianaesthetic management of patients with primary or coexisting pathology of the following endocrine organs: The pancreas with diabetes mellitus as the most common endocrine cause of primary and secondary organ dysfunctions affecting anaesthetic care. Adrenal cortical pathology with excess or deficiency of adrenocortical hormones. Pheochromocytoma of the adrenal medulla with infrequent but challenging perianaesthetic problems. Thyroid gland diseases with hyper- or hypothyroidism. Parathyroid gland pathology with hypercalcaemia or hypocalcaemia. Disorders of the anterior and posterior pituitary gland. The carcinoid syndrome and more uncommon endocrinopathies such as adenomas from the gastroenteropancreatic endocrine tissues and the ovarian hyperstimulation syndrome are also reviewed briefly.

Anesthesia↗