Atropine and hyoscine

Antispasmodics for Chronic Abdominal Pain: Analysis of North American Treatment Options

Chronic abdominal pain is a common gastrointestinal (GI) symptom that characterizes many functional GI disorders/disorders of gut-brain interaction, including irritable bowel syndrome, functional dyspepsia, and centrally mediated abdominal pain syndrome. The symptoms of abdominal pain in these highly prevalent disorders are often treated with antispasmodic agents. Antispasmodic treatment includes a broad range of therapeutic classes with different mechanisms of action, including anticholinergic/antimuscarinic agents (inhibition of GI smooth muscle contraction), calcium channel inhibitors (inhibition of calcium transport into GI smooth muscle), and direct smooth muscle relaxants (inhibition of sodium and calcium transport). The aim of this review article was to examine the efficacy and safety of antispasmodics available in North America (e.g., alverine, dicyclomine, hyoscine, hyoscyamine, mebeverine, otilonium, pinaverium, and trimebutine) for the treatment of chronic abdominal pain in patients with common disorders of gut-brain interaction. For the agents examined, comparisons of studies are limited by inconsistencies in treatment dosing and duration, patient profiles, and diagnostic criteria employed. Furthermore, variability in study end points limits comparisons. Risk of selection, performance, detection, attrition, and reporting bias also differed among studies, and in many cases, risks were considered "unclear." The antispasmodics evaluated in this review, which differ in geographic availability, were found to vary dramatically in efficacy and safety. Given these caveats, each agent should be considered on an individual basis, rather than prescribed based on information across the broad class of agents.

Rigid Scaffolds: Synthesis of 2,6-Bridged Piperazines with Functional Groups in all three Bridges

The activity of pharmacologically active compounds can be increased by presenting a drug in a defined conformation, which fits exactly into the binding pocket of its target. Herein, the piperazine scaffold was conformationally restricted by substituted C2- or C3-bridges across the 2- and 6-position. At first, a three-step, one-pot procedure was developed to obtain reproducibly piperazine-2,6-diones with various substituents at the N-atoms in high yields. Three strategies for bridging of piperazine-2,6-diones were pursued: 1. The bicyclic mixed ketals 8-benzyl-6-ethoxy-3-(4-methoxybenzyl)-6-(trimethylsilyloxy)-3,8-diazabicyclo[3.2.1]octane-2,4-diones were prepared by Dieckmann analogous cyclization of 2-(3,5-dioxopiperazin-2-yl)acetates. 2. Stepwise allylation, hydroboration and oxidation of piperazine-2,6-diones led to 3-(3,5-dioxopiperazin-2-yl)propionaldehydes. Whereas reaction of such an aldehyde with base provided the bicyclic alcohol 9-benzyl-6-hydroxy-3-(4-methoxybenzyl)-3,9-diazabicyclo[3.3.1]nonane-2,4-dione in only 10 % yield, the corresponding sulfinylimines reacted with base to give N-(2,4-dioxo-3,9-diazabicyclo[3.3.1]nonan-6-yl)-2-methylpropane-2-sulfinamides in >66 % yield. 3. Transformation of a piperazine-2,6-dione with 1,4-dibromobut-2-ene and 3-halo-2-halomethylprop-1-enes provided 3,8-diazabicyclo[3.2.1]octane-2,4-dione and 3,9-diazabicyclo[3.3.1]nonane-2,4-dione with a vinyl group at the C2- or a methylene group at the C3-bridge, respectively. Since bridging via sulfinylimines and the one-pot bridging with 3-bromo-2-bromomethylprop-1-ene gave promising yields, these strategies will be exploited for the synthesis of novel receptor ligands bearing various substituents in a defined orientation at the carbon bridge.

Use of Natural Products in Asthma Treatment

Asthma, a disease classified as a chronic inflammatory disorder induced by airway inflammation, is triggered by a genetic predisposition or antigen sensitization. Drugs currently used as therapies present disadvantages such as high cost and side effects, which compromise the treatment compliance. Alternatively, traditional medicine has reported the use of natural products as alternative or complementary treatment. The aim of this review was to summarize the knowledge reported in the literature about the use of natural products for asthma treatment. The search strategy included scientific studies published between January 2006 and December 2017, using the keywords "asthma," "treatment," and "natural products." The inclusion criteria were as follows: (i) studies that aimed at elucidating the antiasthmatic activity of natural-based compounds or extracts using laboratory experiments (in vitro and/or in vivo); and (ii) studies that suggested the use of natural products in asthma treatment by elucidation of its chemical composition. Studies that (i) did not report experimental data and (ii) manuscripts in languages other than English were excluded. Based on the findings from the literature search, aspects related to asthma physiopathology, epidemiology, and conventional treatment were discussed. Then, several studies reporting the effectiveness of natural products in the asthma treatment were presented, highlighting plants as the main source. Moreover, natural products from animals and microorganisms were also discussed and their high potential in the antiasthmatic therapy was emphasized. This review highlighted the importance of natural products as an alternative and/or complementary treatment source for asthma treatment, since they present reduced side effects and comparable effectiveness as the drugs currently used on treatment protocols.

Toxicity and median effective doses of oxime therapies against percutaneous organophosphorus pesticide and nerve agent challenges in the Hartley guinea pig

Anticholinesterases, such as organophosphorus pesticides and warfare nerve agents, present a significant health threat. Onset of symptoms after exposure can be rapid, requiring quick-acting, efficacious therapy to mitigate the effects. The goal of the current study was to identify the safest antidote with the highest therapeutic index (TI = oxime 24-hr LD50/oxime ED50) from a panel of four oximes deemed most efficacious in a previous study. The oximes tested were pralidoxime chloride (2-PAM Cl), MMB4 DMS, HLö-7 DMS, and obidoxime Cl2. The 24-hr median lethal dose (LD50) for the four by intramuscular (IM) injection and the median effective dose (ED50) were determined. In the ED50 study, male guinea pigs clipped of hair received 2x LD50 topical challenges of undiluted Russian VX (VR), VX, or phorate oxon (PHO) and, at the onset of cholinergic signs, IM therapy of atropine (0.4 mg/kg) and varying levels of oxime. Survival was assessed at 3 hr after onset clinical signs. The 3-hr 90th percentile dose (ED90) for each oxime was compared to the guinea pig pre-hospital human-equivalent dose of 2-PAM Cl, 149 µmol/kg. The TI was calculated for each OP/oxime combination. Against VR, MMB4 DMS had a higher TI than HLö-7 DMS, whereas 2-PAM Cl and obidoxime Cl2 were ineffective. Against VX, MMB4 DMS > HLö-7 DMS > 2-PAM Cl > obidoxime Cl2. Against PHO, all performed better than 2-PAM Cl. MMB4 DMS was the most effective oxime as it was the only oxime with ED90 < 149 µmol/kg against all three topical OPs tested.

Analysis of spatiotemporal pattern and quantification of gastrointestinal slow waves caused by anticholinergic drugs

Anticholinergic drugs are well-known to cause adverse effects, such as constipation, but their effects on baseline contractile activity in the gut driven by slow waves is not well established. In a video-based gastrointestinal motility monitoring (GIMM) system, a mouse's small intestine was placed in Krebs solution and recorded using a high definition camera. Untreated controls were recorded for each specimen, then treated with a therapeutic concentration of the drug, and finally, treated with a supratherapeutic dose of the drug. Next, the video clips showing gastrointestinal motility were processed, giving us the segmentation motions of the intestine, which were then converted via Fast Fourier Transform (FFT) into their respective frequency spectrums. These contraction quantifications were analyzed from the video recordings under standardised conditions to evaluate the effect of drugs. Six experimental trials were included with benztropine and promethazine treatments. Only the supratherapeutic dose of benztropine was shown to significantly decrease the amplitude of contractions; at therapeutic doses of both drugs, neither frequency nor amplitude was significantly affected. We have demonstrated that intestinal slow waves can be analyzed based on the colonic frequency or amplitude at a supratherapeutic dose of the anticholinergic medications. More research is required on the effects of anticholinergic drugs on these slow waves to ascertain the true role of ICC in neurologic control of gastrointestinal motility.

Assessing the therapeutic efficacy of oxime therapies against percutaneous organophosphorus pesticide and nerve agent challenges in the Hartley guinea pig

Given the rapid onset of symptoms from intoxication by organophosphate (OP) compounds, a quick-acting, efficacious therapeutic regimen is needed. A primary component of anti-OP therapy is an oxime reactivator to rescue OP-inhibited acetylcholinesterases. Male guinea pigs, clipped of hair, received neat applications of either VR, VX, parathion, or phorate oxon (PHO) at the 85(th) percentile lethal dose, and, beginning with presentation of toxicosis, received the human equivalent dose therapy by intramuscular injection with two additional follow-on treatments at 3-hr intervals. Each therapy consisted of atropine free base at 0.4 mg/kg followed by one of eight candidate oximes. Lethality rates were obtained at 24 hr after VR, VX and PHO challenges, and at 48 hr after challenge with parathion. Lethality rates among symptomatic, oxime-treated groups were compared with that of positive control (OP-challenged and atropine-only treated) guinea pigs composited across the test days. Significant (p ≤ 0.05) protective therapy was afforded by 1,1-methylene bis(4(hydroxyimino- methyl)pyridinium) dimethanesulfonate (MMB4 DMS) against challenges of VR (p ≤ 0.001) and VX (p ≤ 0.05). Lethal effects of VX were also significantly (p ≤ 0.05) mitigated by treatments with oxo-[[1-[[4-(oxoazaniumylmethylidene)pyridin-1-yl]methoxymethyl]pyridin-4-ylidene]methyl]azanium dichloride (obidoxime Cl2) and 1-(((4-(aminocarbonyl) pyridinio)methoxy)methyl)-2,4-bis((hydroxyimino)methyl)pyridinium dimethanesulfonate (HLö-7 DMS). Against parathion, significant protective therapy was afforded by obidoxime dichloride (p ≤ 0.001) and 1,1'-propane-1,3-diylbis{4-[(E)-(hydroxyimino)methyl]pyridinium} dibromide (TMB-4, p ≤ 0.01). None of the oximes evaluated was therapeutically effective against PHO. Across the spectrum of OP chemicals tested, the oximes that offered the highest level of therapy were MMB4 DMS and obidoxime dichloride.

The therapeutic value of atropine for critical care intubation

Recent studies of atropine during critical care intubation (CCI) have revealed that neonates frequently experience bradycardia, are infrequently affected by ventricular arrhythmias and conduction disturbances and deaths have not been reported in a series of studies. The indiscriminate use of atropine is unlikely to alter the outcome during neonatal CCI other than reducing the frequency of sinus tachycardia. In contrast, older children experience a similar frequency of bradycardia to neonates and are more frequently affected by ventricular arrhythmias and conduction disturbances. Mortality during CCI is in the order of 0.5%. Atropine has a beneficial effect on arrhythmias and conduction disturbances and may reduce paediatric intensive care unit mortality. The use of atropine for children >1 month of age may positively influence outcomes beyond a reduction in the frequency of sinus bradycardia. There is indirect evidence that atropine should be used for intubation during sepsis. Atropine should be considered when using suxamethonium. The reliance on heart rate as the sole measure of haemodynamic function during CCI is no longer justifiable. Randomised trials of atropine for mortality during CCI in general intensive care unit populations are unlikely to happen. As such, future research should be focused on establishing of a gold standard for haemodynamic decompensation for CCI. Cardiac output or blood pressure are the most likely candidates. The 'lost beat score' requires development but has the potential to be developed to provide an estimation of risk of haemodynamic decompensation from ECG data in real time during CCI.

Administration of hyoscine- n-butylbromide during colonoscopy: a survey of current UK practice

OBJECTIVE

Current British Society of Gastroenterology (BSG) guidelines suggest that hyoscine-n-butylbromide (Buscopan) should be avoided during colonoscopy in patients with a history of angle-closure glaucoma. Angle-closure glaucoma, however, is not very common, is asymptomatic before onset and is treated definitively by a single laser treatment (if spotted early). Open-angle glaucoma is not affected by hyoscine. The aim of this study was to assess the use of hyoscine among colonoscopists, with particular reference to glaucoma.

DESIGN AND SETTING

Following BSG endoscopy subcommittee approval, a short questionnaire was electronically administered to members of the BSG and the Association of Coloproctology of Great Britain and Ireland.

MAIN OUTCOME MEASURES

Hyoscine use among colonoscopists, and effect of glaucoma history upon prescribing practice.

RESULTS

188 colonoscopists responded to some or all of the questions. 123/183 (67.2%) of respondents claimed they were aware of the BSG guidelines. 160/187 (85.6%) sometimes or always use hyoscine, while 27/187 (14.4%) never do. 137/177 (77.4%) always enquire about glaucoma history prior to administration, although 147/176 (83.0%) make no differentiation between open-angle or angle-closure forms. 126/178 (70.8%) would (incorrectly) withhold hyoscine if the patient declares a history of any form of glaucoma. 140/179 (78.2%) do not substitute glucagon as an antispasmodic. 4/180 (2.2%) had encountered ophthalmic complications post-administration.

CONCLUSIONS

Current BSG guidelines pertaining to hyoscine use and glaucoma are inappropriate; the authors recommend revision. Patients undergoing colonoscopy who have received hyoscine should, instead, be advised to seek urgent medical advice if they develop ophthalmic symptoms.

Secrets of safe laparoscopic surgery: Anaesthetic and surgical considerations

In recent years, laparoscopic surgery has gained popularity in clinical practice. The key element in laparoscopic surgery is creation of pneumoperitoneum and carbon dioxide is commonly used for insufflation. This pneumoperitoneum perils the normal cardiopulmonary system to a considerable extent. Every laparoscopic surgeon should understand the consequences of pneumoperitoneum; so that its untoward effects can be averted. Pneumoperitoneum increases pressure on diaphragm, leading to its cephalic displacement and thereby decreasing venous return, which can be aggravated by the position of patient during surgery. There is no absolute contraindication of laparoscopic surgery, though we can anticipate some problems in conditions like obesity, pregnancy and previous abdominal surgery. This review discusses some aspects of the pathophysiology of carbon dioxide induced pneumoperitoneum, its consequences as well as strategies to counteract them. Also, we propose certain guidelines for safe laparoscopic surgery.

Determination of scopolamine in human serum and microdialysis samples by liquid chromatography-tandem mass spectrometry

A liquid chromatographic-tandem mass spectrometric (LC-MS-MS) method with a rapid and simple sample preparation was developed for the determination of scopolamine in biological fluids. Scopolamine and the internal standard atropine in serum samples were extracted and cleaned up by using an automated solid phase extraction method. Microdialysis samples were directly injected into the LC-MS system. The mass spectrometer was operated in the multi reaction monitoring mode. A good linear response over the range of 20 pg/ml to 5 ng/ml was demonstrated. The accuracy for added scopolamine ranged from 95.0 to 104.0%. The lower limit of quantification was 20 pg/ml. This method is suitable for pharmacokinetic studies.

Routine suxamethonium in children. A regional survey of current usage

This survey aimed to assess the extent and pattern of use of suxamethonium for elective tracheal intubation in children and the occurrence of major complications. A postal questionnaire was sent to 280 consultant anaesthetists and senior registrars in the West Midlands Region. Of the 180 replies received, 84% of respondents use suxamethonium routinely. Usage was more common amongst those more recently trained (all anaesthetists with less than 10 years experience reported using suxamethonium for routine intubation compared with 81% of those with over 20 years experience). Reported side effects directly attributable to suxamethonium were common, the most frequent being cardiac arrhythmias (especially bradycardia) following the first dose (24% respondents) or the second dose (43%), and prolonged apnoea (36% of respondents). There were 13 reported cardiac arrests (requiring external cardiac massage), three of which were associated with repeat dosing and one with undiagnosed Duchenne muscular dystrophy. Three cases of documented hyperkalaemia did not lead to cardiac arrest. There were two deaths, neither of which could be solely attributed to the use of suxamethonium. We conclude that suxamethonium remains popular in paediatric practice and that minor side effects are common and usually preventable. Life-threatening reactions are rare and until a truly comparable alternative is produced this drug will continue to be used in children.

Determination of scopolamine in human serum by gas chromatography-ion trap tandem mass spectrometry

The objective of this study was to develop a very sensitive and selective method for the determination of scopolamine in serum with a rapid and simple sample preparation. A capillary column gas chromatographic-ion trap tandem mass spectrometric technique has been applied. Scopolamine and the internal standard mexiletine were extracted from serum samples and cleaned up by using a single step liquid-liquid extraction. Derivatization was carried out using 2,2,2-trifluoro-N-methyl-N-trimethylsilylacetamide. The mass spectrometer was operated with positive ions in the selected reaction mode with chemical ionisation using methane. The sum of peak height of two daughter ions was used for quantification. The detection limit was 50 pg/ml in serum.

A placebo-controlled trial using intravenous atropine as an adjunct to conscious sedation in pediatric esophagogastroduodenoscopy

BACKGROUND

The usefulness of intravenous atropine as an adjunct to conscious sedation in pediatric esophagogastroduodenoscopy remains an unresolved issue.

METHODS

This prospective, double-blind, randomized study examined 101 patients, who were randomized to receive either intravenous atropine 0.02 mg/kg (maximum 0.4 mg) or a placebo of normal saline solution prior to the procedure.

RESULTS

The mean maximum heart rate during the procedure and the percentage of time that the heart rate was more than 1 standard deviation above mean for age was significantly greater in the atropine group as compared to the placebo group (p < 0.0005). There was no significant difference between groups in the amount of secretions noted, gastric motility, retching or vomiting, facial flushing, or dysphoria. There were no causes of significant bradycardia or hypotension in either group. There was a significant number of patients greater than 5 years of age and receiving meperidine and atropine (as compared with meperidine and placebo) whose arterial oxygen saturation dropped below 90% during the procedure (p = 0.0485).

CONCLUSIONS

We found that the use of atropine when used as an adjunct to conscious sedation in children undergoing upper endoscopy did not increase the safety of the procedure or provide significant benefits. We do not recommend the routine use of atropine for upper endoscopy in pediatric patients.

Paralytic ileus as a complication of atropine therapy following severe organophosphate poisoning

A 32-year-old man presented with symptoms of severe organophosphate poisoning and required an atropine infusion for 5 weeks. We believe the development of a paralytic ileus occurred as a rare feature of atropine toxicity when other signs were masked by the underlying condition. The onset of a paralytic ileus coincided with a spontaneous increase in red cell cholinesterase levels and may be an early sign of recovery from organophosphate poisoning.

Pharmacokinetics and related pharmacodynamics of anticholinergic drugs

The pharmacokinetics and some pharmacodynamic properties of atropine, glycopyrrolate and scopolamine are reviewed. With the development of new analytical methods for drug determination, it is now possible to measure relatively low concentrations of these drugs in biological fluids and, consequently, some new kinetic data have been collected. Following intravenous administration, a fast disappearance from the circulation is observed and due to a high total clearance value their elimination phase half-lives vary from 1 to 4 h. All these agents are nonselective muscarinic receptor antagonists, but their actions on various organ systems with cholinergic innervation show considerable diversity. The cardiovascular effects are of short duration; other peripheral muscarinic effects and CNS effects can last up to 8 h or even longer. Differing from atropine and scopolamine, glycopyrrolate as a quaternary amine penetrates the biological membranes (blood-CNS, placental barriers) slowly and incompletely, making it the drug of choice for elderly patients with coexisting diseases and for obstetric use. Similarly, its oral absorption is slow and erratic, and hence it cannot be used as an oral premedicant. Atropine, scopolamine and glycopyrrolate have a definitely faster absorption rate, when injected into the deltoid muscle compared with administration into the gluteal or vastus lateralis muscles. There appear to be significant differences in the metabolism and renal excretion of these agents. Scopolamine is apparently excreted into the urine mainly as inactive metabolites, nearly half of the atropine dose administered is recovered in the urine as the parent drug or as active metabolites and about 80% of glycopyrrolate is excreted as unchanged drug or active metabolites.(ABSTRACT TRUNCATED AT 250 WORDS)

Anaesthesia for laparoscopic general surgery

Laparoscopic surgery minimises postoperative morbidity. Patient benefits include reduction in postoperative pain, better cosmetic result and quicker return to normal activities. Hospital stay is shortened resulting in a reduction in overall medical cost. The intraoperative requirements of laparoscopic surgery however can lead to serious physiological changes and complications. While there is a low but definite perioperative mortality rate associated with minor gynaecologic laparoscopic procedures, laparoscopic general surgical procedures are performed on older patients and patients with acute surgical conditions and are likely to be associated with a higher incidence of perioperative complications. The major problems during laparoscopic surgery are related to the cardiopulmonary effects of pneumoperitoneum, systemic carbon dioxide absorption, extraperitoneal gas insufflation, venous gas embolism and unintentional injuries to intra-abdominal structures. An appraisal of the potential problems is essential for optimal anaesthetic care of patients undergoing laparoscopic surgery. Appropriate anaesthetic techniques and monitoring facilitate surgery and allow early detection and reduction of complications. The need for rapid recovery and short hospital stay impose additional demands on the anaesthetist for skillful practice.

Clinical and metabolic responses to different kinds of premedication in ASA III patients

Clinical and metabolic responses to atropine plus pethidine and to scopolamine plus morphine premedication were studied in 45 ASA physical status III patients undergoing gynaecological procedures. Atropine 0.5 mg plus pethidine 50 mg intramuscularly (Group 1), scopolamine 0.24 mg plus morphine 8 mg (Group 2), or intramuscular placebo (Group 3) premedication were given in random, double-blind fashion. Scopolamine-morphine premedication caused a significant decrease in energy expenditure (EE) and oxygen consumption (VO2) (from 1229 +/- 193 to 1184 +/- 221 kcal/24 h, P = 0.004 and from 105 +/- 11 to 102 +/- 12 ml/min/m2, P = 0.006, respectively) simultaneously with a decrease in rate-pressure product (RPP) (P = 0.0001) and an increase in pressure-rate quotient (PRQ) (P = 0.034). Atropine-pethidine premedication induced a decrease in RPP but not in EE or VO2. In the placebo group both RPP and VO2 first increased and then slowly returned to the levels measured prior to premedication. The RPP was significantly lower in Group 2 than in Groups 1 and 3 at both 30 and 60 min. The degrees of subjective tiredness and anxiolysis were significantly greater in Groups 1 and 2 (showing good sedative and anxiolytic effect) than in Group 3. These results show that in ASA III patients, atropine-pethidine premedication does not decrease the sympathoadrenal reaction to the degree its anxiolytic and sedative effect would suggest. This may indicate neuroendocrine stress induced by atropine-pethidine.

Effects of glycopyrrolate and atropine on heart rate variability

Analysis of heart rate variability, combined with physiological tests (deep breathing and tilt tests) was used to characterise the effects of atropine and glycopyrrolate on the parasympathetic nervous tone of the heart in healthy male volunteers. The low dose of atropine (120 micrograms) administered as a continuous infusion in 15 min was associated with parasympatomimetic effects estimated by the slowing of the heart rate and an increase of the mean and beat-to-beat heart rate variability. The bradycardia and increase of heart rate variability following infusion of glycopyrrolate (50 micrograms) was less marked and did not differ significantly from that of placebo. The higher doses of atropine (720 micrograms) and glycopyrrolate (300 micrograms) administered as a continuous infusion in 15 min produced an equal vagal cardiac blockade characterised by significant tachycardia and a decrease in overall and beat-to-beat heart rate variability. It is concluded that at low doses the parasympatomimetic action of glycopyrrolate is less marked than that of atropine; and at higher doses only small differences exist between these two muscarinic antagonists in their effects on cardiac vagal outflow, assessed by heart rate and heart rate variability.

Anticholinergic premedication in Finland 1988

In order to investigate the present use of anticholinergic drugs in premedication, a questionnaire was sent to Finnish anaesthesiologists. The results indicate that there is significant variation between different parts of the country regarding the usage of these drugs. A decrease in routine use has taken place over the past 5 years. Half of the anaesthesiologists now routinely use anticholinergic drugs in premedication, while 69% were using them 5 years ago. Glycopyrrolate has gained popularity and was the most used drug. Most anaesthesiologists gave the anticholinergic premedication intravenously, briefly before induction.

Pharmacokinetics of scopolamine during caesarean section: relationship between serum concentration and effect

The pharmacokinetics (radioreceptor assay, RRA) and some of the clinical effects of the anticholinergic agent, scopolamine, were studied in 16 parturients during caesarean section. Following a single 0.005 mg/kg intramuscular injection (deltoid muscle), a very fast rate of absorption was found with mean peak serum concentrations occurring after only 10 min (n = 6). Due to severe bradycardia, 0.5 mg of atropine i.v. had to be given in addition to the i.m. scopolamine treatment to one parturient. The RRA measured the total concentration produced by the two anticholinergic agents in both serum and urine. There was a fundamental difference in the diffusion of scopolamine through the placenta and the blood-lumbar (CSF-barrier (n = 15). There was significant drug penetration in the foeto-placental unit, indicating an efficient drug transfer to the child, but there were measurable levels of the drug in the lumbar CSF in only three cases. The apparent elimination phase half-life of scopolamine in serum was only around 1 h. The urinary excretion of scopolamine and/or its antimuscarinic metabolites lasted only for 6 h (2.63 +/- 1.14% of the dose). The onset of the clinical effects of scopolamine appeared to be delayed, but long-lasting in contrast to the rapid absorption and quick disappearance from the serum. Both the heart rate changes, sedative and antisialogogue effects and serum concentrations did not show any correlation. There appears to be a surprisingly great difference between the pharmacokinetic parameters and the clinical effects of scopolamine.

Intramuscular atropine in elderly people: pharmacokinetic studies using the radioreceptor assay and some pharmacodynamic responses

The pharmacokinetics (radioreceptor assay, RRA) and some clinical effects of atropine were studied in 7 elderly gynaecological surgery patients. The RRA measures only the pharmacologically active isomer of atropine, 1-hyoscyamine. Following a single 0.01 mg/kg intramuscular (M. deltoideus) injection, a very fast rate of absorption was found with mean peak serum concentration occurring after only 13 min. The reason for this could be either a preferential tissue uptake of the 1-form or the injection site or both. The elimination half-life was 2.27 hr. Only 23.1% of the given drug was excreted in urine in 24 hr as a pharmacologically active form. The clinical effects (heart rate rise, subjective sedation and antisialogogue effect) were seen after only 30 min. This somewhat faster appearance of clinical effects than in previous studies can be due to the injection site. The sedative effect of the drug is clear and long lasting in elderly people.

Reduction of ventricular arrhythmias by atropine during coronary arteriography

Sustained ventricular arrhythmia is a well-recognized complication of cardiac catheterization, often occurring after selective coronary artery injection of contrast medium. The role of autonomic reflexes in the pathogenesis of this phenomenon is unclear. Although the muscarinic antagonist atropine is often administered prophylactically before coronary angiography to reduce the likelihood of sinus bradycardia and vasovagal reactions, its influence on ventricular arrhythmias in this setting has not been established. This case-control trial studied 648 patients undergoing coronary arteriography to investigate this issue. Eleven case subjects (those with ventricular tachyarrhythmia) were identified. Control subjects (those without ventricular tachyarrhythmia) were matched for baseline heart rate (+/- 6 beats/min), age (+/- 10 years), sex and calendar year of procedure using a 1:3 sampling ratio. All 26 potential clinical, anatomic and hemodynamic covariates were statistically similar between groups. Ventricular tachyarrhythmias were more likely to occur after selective right coronary injection (odds ratio 15.1, p = 0.0008) but not after multiple contrast injections (odds ratio 0.918, difference not significant). Most importantly, atropine sulfate was administered prophylactically to 18 of 33 control subjects (55 +/- 9%) but only 1 of 11 cases (9 +/- 9%), generating a significant odds ratio of 12.0 (p = 0.02). Thus, the odds of experiencing sustained ventricular tachyarrhythmias during coronary arteriography may potentially be reduced 12-fold by prior administration of atropine, even in patients with normal baseline heart rates.

Pharmacokinetic implications for the clinical use of atropine, scopolamine and glycopyrrolate

Several specific and sensitive new methods for determining atropine and its metabolites in biological fluids have increased the possibility to characterise the pharmacokinetic properties of this antimuscarinic agent. Following i.v. injection, atropine disappears very quickly from the circulation, resembling its fast onset of action. Age, but not sex, appears to have a clear effect on its kinetics, explaining at least partly the higher sensitivity of very young and very old patients to this anticholinergic agent. Following i.m. or oral atropine administration, typical anticholinergic effects coincide quite well with the absorption rate of the drug, indicating that the premedication should be given about 1 and 2 h before induction of anaesthesia. A sufficient absorption after rectal administration offers an alternative treatment, especially in children. Differing from its placental transfer, atropine has a delayed and incomplete lumbar cerebrospinal fluid penetration, indicating a fundamental difference between these two biological membranes. Oropharyngeally administered atropine has a very variable absorption, but inhaled or intratracheally given drug has produced interesting new results, e.g. pulmonary atropine administration appears to have clinical significance in special situations, such as cardiac arrest and organophosphate poisoning (military personnel). Depending on the method used, different data on the metabolism and excretion for atropine have been reported and therefore further studies are needed in this respect. The pharmacokinetics of scopolamine and glycopyrrolate and their relation to clinical response are poorly understood.

Elimination of and heart rate response to atropine in the elderly are independent of sex

Sex-related changes in the pharmacokinetics and pharmacodynamics (heart rate) of atropine were studied in female (n = 9) and male (n = 9) elderly patients after a single 0.02 mg/kg i.v. injection of the drug at the beginning of a combination anaesthesia. No significant differences were found between the sexes, which indicates that there are no sex-related alterations in the response to this anticholinergic agent.

The use of oral benzodiazepines as premedications: the usefulness of temazepam

The primary aim of premedication is to relieve the patient's anxiety/restlessness before anaesthesia and to ensure optimum quantity and quality of sleep on the night preceding surgery. With these objectives in mind, oral benzodiazepines offer a good alternative to traditional parenteral premedicants, especially as the clear anxiolytic and sedative effects of the former are of great clinical value. Oral temazepam has proven to be a valuable premedicant given on the evening before operation and/or the following morning, before surgery. Administered as a sedative in a single 20 mg oral dose the night before surgery, temazepam provided a good night's sleep in 77 percent of gynaecological surgical patients; patients slept for 7.6 hours and had no significant residual effects. As a premedicant, temazepam was as effective as parenteral diazepam or papaveretum. Temazepam's short duration of action facilitates rapid postoperative recovery in children, adults, and in the elderly. Thus, it is indicated especially for short operative procedures when rapid recovery and swift return to fitness are essential.

Pharmacokinetics and clinical effects of scopolamine in caesarean section patients

A new method (ELISA) was used to evaluate the pharmacokinetics of scopolamine following intravenous (0.005 mg/kg), intramuscular (0.01 mg/kg), and oropharyngeal (0.035 mg/kg) administration of the drug to pregnant patients anaesthetized for caesarean section. After intravenous (N = 4) the drug fast disappeared from the circulation with a half-life of about 5 min., and the serum levels generally were measurable up to 3 hours, mean elimination half-life was 1.85 hours. A fast absorption was found after intramuscular injection, tmax = 10 min. (N = 4), and the drug had a clinically significant oropharyngeal absorption as well, tmax was around 1 hour (N = 6). The intramuscular and oropharyngeal, but not the intravenous, administrations produced a marked postoperative sedative and amnesic effects. All three administration ways caused a significant antisecretory action.

The effects of transdermal scopolamine and four dose levels of oral scopolamine (0.15, 0.3, 0.6, and 1.2 mg) upon psychological performance

Four dose levels of oral scopolamine (0.15 mg, 0.3 mg, 0.6 mg, 1,2 mg), transdermal scopolamine, and placebo, were investigated for their effects upon a battery of psychological performance measures in normal subjects. Oral scopolamine produced significant linear dose-related decrements on tasks involving continuous attention, continuous performance, memory storage for new information, and on self-rated feelings of alertness and sociability. Transdermal scopolamine produced significant performance impairments on these same assessment measures. Resting heart rate levels were significantly reduced by all scopolamine conditions. Side effects (dry mouth, dizziness) were frequent following transdermal scopolamine and the higher oral dose conditions. The overall effects of the transdermal scopolamine patch were broadly equivalent to the effects of 0.8 mg oral scopolamine. This oral dose equivalence for transdermal scopolamine is higher than expected, and possible reasons for this are discussed.

The influence of body weight on plasma concentration of atropine after rectal administration in children

To avoid an unpleasant injection, the rectal administration of drugs to children is often to be preferred. Very little has been published on plasma concentrations of atropine given rectally. To determine whether body weight has any influence on the plasma concentrations of atropine, 18 children weighing 7.5-55.0 kg were given 0.02 mg atropine sulphate per kg rectally, and the plasma levels of atropine were determined. The mean peak plasma concentration of atropine was 1.17 ng/ml and it was reached after 33 min. In the group of smaller children (b.w. less than 15 kg) the peak plasma concentration was (0.83 ng/ml) lower than that observed in older children (1.26-1.36 ng/ml), but this difference was not statistically significant. Plasma concentrations in the group of smaller children declined significantly faster than in the other weight groups.

Failure of IV atropine to abolish nasal irritation caused by chlormethiazole infusion in elderly patients undergoing spinal anaesthesia

The efficacy of intravenous atropine in abolishing the nasal irritation of chlormethiazole was assessed. Forty elderly patients undergoing transurethral resection of prostate under spinal anaesthesia were studied. One ml of either atropine sulphate (0.6 mg) or normal saline was administered intravenously in a double-blind fashion 10 minutes prior to infusion of 0.8% chlormethiazole edisylate. A loading infusion of 5 ml X min-1 of the chlormethiazole solution was followed by a variable rate of infusion in order to maintain a predetermined state of sedation--i.e. where the patient lapsed into sleep but was easily awakened to obey commands. Sneezing was the commonest side-effect occurring in 45% and 70% of patients in atropine and saline groups respectively. This was not effectively abolished by IV atropine in incremental doses of 0.6 mg up to 1.8 mg. Because of the sneezing and restlessness, four patients in the atropine group required general anaesthesia to improve operating conditions. These side-effects of chlormethiazole may limit its use as a sedative for surgery in this elderly age group.

Midazolam versus atropine plus pethidine as premedication in children

The effects of oral midazolam or intramuscular atropine and pethidine used as premedication in two groups of 35 children over 5 years of age were studied. There was some evidence that the anxiolytic effect of midazolam was rather better than that of atropine plus pethidine, but, in other respects, subjective assessments in the two patient groups were similar. Intramuscular atropine caused tachycardia and subjective side-effects, nevertheless children appear to require anticholinergics during premedication because of excessive salivary secretion, especially during extubation. Oral midazolam is a new anxiolytic drug which can be used as an alternative to existing premedicant drugs, but, in children, it should still be combined with an anticholinergic agent. No correlation between serum levels of midazolam or atropine and their clinical effects was found.

Scopolamine intoxications

Pure scopolamine intoxications are extremely rare. We treated a series of severe intoxications exclusively caused by scopolamine and due to the intentional mixing of pure scopolamine into drinks. The clinical course and therapy are reported. On the basis of our experience and a survey of literature, we found physostigmine to be an excellent antidote. The symptomatology of the patients confirms that scopolamine has a dose-related stimulant effect on the central nervous system.

Psychomotor, physiological and cognitive effects of scopolamine and ephedrine in healthy man

Three placebo-controlled double-blind studies in healthy volunteers were performed to reveal the psychophysiological effects of scopolamine, ephedrine and their combination. Single intravenous dose of scopolamine 6 micrograms/kg (scopolamine hydrobromide 7.4 micrograms/kg) impaired various psychomotor functions both subjectively and objectively. It caused sedation, impairment of coordinative and reactive skills, visual disturbances and impairment of shortterm memory. Oral scopolamine hydrobromide in single doses of 0.3 mg and 0.9 mg, or 0.9 mg b.d. for 3 days, had few effects. A slight impairment of shortterm memory and a decrease in the flicker fusion threshold were seen. The visual nearpoint and pupil diameter were increased and some subjects reported blurred vision and dizziness during treatment with scopolamine 0.9 mg b.d. Scopolamine showed clear cardiovascular effects in all studies: it decreased heart rate and systolic blood pressure. Ephedrine alone and in combination with scopolamine had no deleterious effects. On the contrary, it antagonized the scopolamine-induced impairment in the flicker fusion test and the decrease in blood pressure and heart rate. In sufficient doses scopolamine impairs various psychomotor and cognitive skills. An oral dose of scopolamine hydrobromide 0.9 mg on average has few effects, although they may be very striking in certain individuals. To avoid unwanted effects and diminution in performance by scopolamine, doses less than 0.9 mg should be used.

Pharmacokinetic studies on atropine with special reference to age

Pharmacokinetic studies on atropine were performed in 52 patients under general or spinal anaesthesia. Age had a clinically significant effect on the kinetics of this alkaloid: in children under 2 years of age and in the elderly a prolonged elimination was found. This might explain, partly at least, the higher sensitivity of these age groups to the effects of atropine. Age had no effect on the serum protein binding of this alkaloid. Atropine was found in human CSF after a single i.m. administration, but not after a single i.v. administration. During anaesthesia after i.v. atropine administration, a diminished cardiovascular response was found in the elderly in comparison with healthy adult patients. This indicates changes also at the cholinergic receptor sites in the elderly.

Corked up: clinical hyoscine poisoning with alkaloids of the native corkwood, Duboisia

Australian native trees of the genus Duboisia contain high concentrations of atropine-like alkaloids, especially hyoscine. Occupational exposure to the dried plant material results in two clinical syndromes: "cork-eye", and being "corked up". Plant abuse, as an intoxicant and hallucinogen, also results in the "corked up" syndrome. This paper presents four cases of the Duboisia syndrome. Central effects and peripheral anticholinergic effects are encountered in both occupational and accidental field exposure. The particular susceptibility of children, and management of the Duboisia poisoning syndrome are discussed.

Atropine--a safe drug

Three children received 1000 times the prescribed dose of atropine sulphate and recovered from the main effects of excitatory behaviour and hallucinations in 48 hours. Diazepam was effective in the control of this behaviour. It is suggested that physostigmine should be available where atropine and hyoscine are used or where overdoses are managed.

Radioimmunoassay for atropine and l-hyoscyamine

A simple, specific and sensitive radioimmunoassay is described for atropine (dl-hyoscyamine) and l-hyoscyamine. Antiserum was obtained from rabbits immunized with an immunogen prepared by coupling l-hyoscyamine to human serum albumin. By using 3H-atropine as tracer, the assay can detect atropine and l-hyoscyamine concentratins down to 9 nmol/l(2.5 ng/ml) in a 0.1 ml serum or plasma sample. The recovery of atropine was near 100% when the drug was added at different concentrations to normal, pooled human plasma. Atropine and l-hyoscyamine are recognized equally well by the antibodies, but some other structurally related drugs (homatropine scopolamine) and atropine hydrolysis products (tropine, tropic acid) do not interfere. The usefulness of the method in pharmacokinetic studies was shown by assaying atropine concentrations in serial serum samples from two patients, who were given 1.3 mg atropine on connection with anaesthesia. A biexponential serum decay curve was demonstrated in both cases with a very rapid distribution phase (t 1/2 0.63 and 1.38 min.) and a much slower elimination phase (t 1/2 1.86 and 2.09 hrs.).