Pharmacokinetics of propofol in severely obese surgical patients.

Background: Existing PK models of propofol include sparse data from very obese patients. The aim of this study was to develop a PK model based on standardised surgical conditions and spanning from normal-weight up to, and including, a high number of very obese patients.

Methods: Adult patients scheduled for laparoscopic cholecystectomy or bariatric surgery were studied.

Dose requirements of alfentanil to eliminate autonomic responses during rapid-sequence induction with thiopental 4 mg/kg and rocuronium 0.6 mg/kg.

Study Objective: Opioids are integral part of anesthesia induction, but information on optimal dosing is limited. We aimed to determine doses of alfentanil needed to eliminate increases in 5 autonomic response variables (plasma concentrations of epinephrine, norepinephrine and vasopressin, arterial blood pressure [ABP], and heart rate) during rapid-sequence induction of anesthesia with thiopental 4 mg/kg and rocuronium 0.6 mg/kg.

Alfentanil during rapid sequence induction with thiopental 4 mg/kg and rocuronium 0.6 mg/kg: tracheal intubation conditions.

Background: Opioids have become an integral part of anaesthesia induction. We aimed to determine the dose of alfentanil needed to obtain perfect tracheal intubation conditions during rapid sequence induction with standard doses of thiopental and rocuronium, where laryngoscopy was initiated 55 s after commencement of drug administration. The influence of covariates (sex, body weight, age, alfentanil plasma concentration at laryngoscopy) was tested.

Reversal of experimental paralysis in a human by intranasal neostigmine aerosol suggests a novel approach to the early treatment of neurotoxic envenomation.

Neurotoxic snake envenomation can result in respiratory failure and death. Early treatment is considered important to survival. Inexpensive, heat-stable, needle-free, antiparalytics could facilitate early treatment of snakebite and save lives, but none have been developed.

Sex-related differences in the relationship between acceleromyographic adductor pollicis train-of-four ratio and clinical manifestations of residual neuromuscular block: a study in healthy volunteers during near steady-state infusion of mivacurium.

Background: Studies in volunteers suggest that train-of-four (TOF) ratios >0.9 are needed to retain normal function of muscles involved in upper airway patency, swallowing, and vital capacity breathing. We determined if sex-related differences exist in the relationship between adductor pollicis (AP) TOF ratio and measures of neuromuscular function commonly used to assess recovery from neuromuscular block.

Measurement of early bone loss around an uncemented femoral stem.

Background And Purpose: Dual-energy X-ray absorptiometry (DXA) is a precise method to study changes in bone mineral density (BMD), including the pattern of bone remodeling around an implant. Results from implant studies are usually presented as changes in BMD as a function of time. The baseline and reference value for such calculations is the first measurement after the operation.

A prospective randomized study comparing electrochemically deposited hydroxyapatite and plasma-sprayed hydroxyapatite on titanium stems.

Background And Purpose: Plasma-sprayed hydroxyapatite (HA) is a successful coating for fixation of uncemented femoral stems. There may be alternative coatings with advantages in bone remodeling and transport of bone-active substances. We investigated whether an electrochemically deposited hydroxyapatite, Bonemaster (BM), might be a safe alternative in total hip arthroplasty.

Relationship between normalized adductor pollicis train-of-four ratio and manifestations of residual neuromuscular block: a study using acceleromyography during near steady-state concentrations of mivacurium.

Background: Baseline acceleromyographic adductor pollicis train-of-four (TOF) ratio varies significantly between individuals and is often greater than unity. Thus, normalization of acceleromyography data is necessary. The relationship between normalized acceleromyographic TOF ratio, lung volumes, and clinical signs of residual neuromuscular block was studied.

[Muscle relaxants].

Background: Muscle relaxants were introduced into clinical anaesthesia for the first time in 1942. The purpose of this article is to provide an overview of the history of muscle relaxants, their mode of action and their role in current anaesthetic practice.

Material And Method: The review is based on clinical experience, own research and a non-systematic literature search using PubMed.

Safety and efficacy of sugammadex for the reversal of rocuronium-induced neuromuscular blockade in cardiac patients undergoing noncardiac surgery.

Background And Objective: The present randomized, safety-assessor blinded, placebo-controlled trial was designed to assess safety and efficacy of sugammadex, a novel selective relaxant-binding agent, in patients with underlying cardiovascular disease undergoing noncardiac surgery.

Methods: Overall, 116 patients (New York Heart Association class II-III) were randomized and received sugammadex 2.0 mg kg (n = 38), sugammadex 4.

Dose of alfentanil needed to obtain optimal intubation conditions during rapid-sequence induction of anaesthesia with thiopentone and rocuronium.

Background: The primary aim of the present study was to determine the dose of alfentanil that must be added to a rapid-sequence induction (RSI) regimen using thiopentone and rocuronium to obtain optimal intubation conditions in >95% of the individuals.

Methods: A total of 60 ASA I patients were randomly allocated to five different alfentanil dose groups (0, 15, 30, 45, or 60 microg kg-1). A blinded dose of alfentanil followed by thiopentone 4 mg kg-1 and rocuronium 1 mg kg-1 was administered in rapid succession, and tracheal intubation was attempted 40 s thereafter.

Impact of hypothermia on the response to neuromuscular blocking drugs.

Muscle strength is reduced during hypothermia, both in the presence and in the absence of neuromuscular blocking drugs. A 2 degrees C reduction in body temperature may double the duration of neuromuscular blockade. Central body and muscle temperatures decline in parallel, as long as peripheral vasoconstriction does not occur.

The endophytic fungus Piriformospora indica reprograms barley to salt-stress tolerance, disease resistance, and higher yield.

Disease resistance strategies are powerful approaches to sustainable agriculture because they reduce chemical input into the environment. Recently, Piriformospora indica, a plant-root-colonizing basidiomycete fungus, has been discovered in the Indian Thar desert and was shown to provide strong growth-promoting activity during its symbiosis with a broad spectrum of plants. Here, we report on the potential of P.

Rocuronium and cisatracurium-positive skin tests in non-allergic volunteers: determination of drug concentration thresholds using a dilution titration technique.

Background: Muscle relaxants are believed to be responsible for 2/3 of the cases of anaphylactic reactions during anesthesia. This assumption is based mainly on positive skin tests obtained in individuals that have experienced anesthesia-related anaphylaxis. A positive skin test is supposed to be associated with mast cell degranulation of vasoactive amines.

The influence of mild hypothermia on the pharmacokinetics and time course of action of neostigmine in anesthetized volunteers.

Background: The pharmacokinetics, maximum effect, and time course of action of neostigmine were studied in seven human volunteers.

Methods: Each volunteer was studied twice, during both normothermia and hypothermia. Anesthesia was induced with 30 microg/kg alfentanil and 3 mg/kg propofol, and was maintained with 60-70% nitrous oxide and 0.

Double-blind comparison of the variability in spontaneous recovery of cisatracurium- and vecuronium-induced neuromuscular block in adult and elderly patients.

Background: This study was designed to compare variability in the offset of two neuromuscular blocking agents with different elimination pathways.

Methods: The spontaneous recovery profiles of cisatracurium and vecuronium were compared in adult (18-64 years) and elderly (> or =65 years) patients receiving N2O/O2/fentanyl/propofol anaesthesia. Patients were randomised to receive an initial bolus dose and maintenance doses of 3xED95, respectively, 0.

Efficacy of tactile-guided reversal from cisatracurium-induced neuromuscular block.

Background: Because tactile evaluation is the most common form of clinical neuromuscular monitoring, this study examines the relative efficacy of antagonizing residual block at different levels of recovery of the tactile train-of-four (TOF) response.

Methods: Anesthesia was induced in 64 adults with 2-5 microg/kg fentanyl and 1-3 mg/kg propofol and maintained with fentanyl, propofol, and nitrous oxide. The tactile response of the adductor pollicis to TOF stimulation was evaluated at one arm, and the mechanomyographic response was recorded at the other.

Hemoglobin desaturation after succinylcholine-induced apnea: a study of the recovery of spontaneous ventilation in healthy volunteers.

Background: Because of the rapid recovery of neuromuscular function after succinylcholine administration, there is a belief that patients will start breathing sufficiently rapidly to prevent significant oxygen desaturation. The authors tested whether this belief was valid.

Methods: Twelve healthy volunteers aged 18-45 yr participated in the study.

Does discontinuation of desflurane at the time of neostigmine administration speed recovery from cisatracurium block compared to that with a propofol-based technique?

Background: Volatile anaesthetics are known to influence the effect of neostigmine as an antagonist of neuromuscular block. The aim of the present study was to investigate whether discontinuation of desflurane at the time of neostigmine administration shortens reversal time from cisatracurium block, compared to that with a propofol-based anaesthesia.

Methods: Ten volunteers were studied twice.

The effects of clonidine on human digital vasculature.

Large concentrations of alpha(2) agonists cause vasoconstriction. However, the threshold of the vasoconstrictive effect in humans is not known. We studied seven volunteers to determine the lower limit of the vasoconstrictive effect of clonidine.

Anaphylactic reactions during induction of anaesthesia using rocuronium for muscle relaxation: a report including 3 cases.

Anaphylaxis during induction of anaesthesia is a dreaded complication with a mortality rate of 3-6%, most frequently associated with the use of muscle relaxants. Current knowledge on this matter is reviewed in relation to the presentation of 3 cases of anaphylaxis and bronchospasm associated with the use of the recently released nondepolarizing muscle relaxant rocuronium. Bronchospasm may be the sole sign of a serious drug reaction, triggered by precipitation of insoluble thiopental crystals when mixed with a muscle relaxant in the intravenous (iv) line.

Temperature-dependent pharmacokinetics and pharmacodynamics of vecuronium.

Background: The authors evaluated the influence of temperature on the pharmacokinetics and pharmacodynamics of vecuronium because mild core hypothermia doubles its duration of action.

Methods: Anesthesia was induced with alfentanil and propofol and maintained with nitrous oxide and isoflurane in 12 healthy volunteers. Train-of-four stimuli were applied to the ulnar nerve, and the mechanical response of the adductor pollicis was measured.

Rapid tracheal intubation with large-dose rocuronium: a probability-based approach.

Unlabelled: There are situations in anesthesia in which it may be desirable to achieve rapid tracheal intubation with perfect conditions, i.e., no coughing or straining.

A comparison of train-of-four monitoring: mechanomyography at the thumb vs acceleromyography at the big toe.

Background: It is not known if the information on neuromuscular function obtained from the hand is interchangeable with that of the foot. In the present study the agreement of thumb mechanomyography with acceleromyography of the big toe was studied.

Methods: Ten healthy patients scheduled for oral surgery were studied.

1 MAC-incision sevoflurane prevents explicit awareness during surgical skin incision and tracheal intubation.

Background: This study tested the hypothesis that 1 MAC-incision anesthesia secures unconsciousness during surgical skin incision and tracheal intubation.

Methods: Twenty patients scheduled for gynecological laparotomy were anesthetized with sevoflurane as the sole agent. At 1 MAC-incision steady-state conditions, the patients were observed for autonomic/movement responses and wakefulness (response to verbal commands) in the 1-min period following surgical skin incision and tracheal intubation.