Pharmacological Interventions for Sialorrhoea in People with Parkinson's Disease: A Systematic Review and Meta-Analysis

Background/objectives

Sialorrhoea is a common non motor complication experienced by people with Parkinson's disease (PD). Despite its prevalence there is conflicting evidence on how to effectively treat it. Our aim was to establish the efficacy and safety outcomes of pharmacological interventions used to treat sialorrhoea in people with idiopathic PD.

Methods

We registered and conducted a systematic review and meta-analysis (PROSPERO: CRD42016042470). We searched seven electronic databases from inception until July 2022. Quantitative synthesis was performed where data allowed using random effects models.

Results

From 1374 records we included 13 studies (n = 405 participants). Studies were conducted in Europe, North America and China. There was marked heterogeneity in the interventions used, follow up times and outcome measures investigated. The main source of risk of bias identified was reporting bias. Five studies were included in the quantitative synthesis. Summary estimates showed administration of botulinum toxin significantly reduced saliva production, improved patient reported functional outcomes and was associated with an increase in adverse events.

Conclusion

Sialorrhoea in PD is an important condition, but current data does not allow for strong recommendations on optimal pharmacological treatments. There is significant heterogeneity in outcomes measures used to evaluate the burden of sialorrhoea with lack of consensus on what constitutes clinically meaningful change. More research is required to better understand the underlying mechanism and potential treatments of sialorrhoea in idiopathic PD.

Vasovagal Reactions during Interventional Pain Management Procedures—A Review of Pathophysiology, Incidence, Risk Factors, Prevention, and Management

Vasovagal reactions are a benign but common outcome of interventional pain management procedures that can negatively impact patient care, including aborted procedures and fear of future procedures that would otherwise help the patient. Research has been done on the incidence, risk factors, and management of vasovagal reactions resulting from such procedures, but less is known about how to prevent these reactions from occurring. In this paper, we present a literature review of the pathophysiology, incidence, risk factors, prevention, and management of vasovagal reactions during interventional pain management procedures, with an emphasis on the relative lack of research and conflicting advice on preventive measures. We found that moderate sedation and anxiolytics have been used prophylactically to prevent vasovagal reactions, but their side-effect profiles prevent them from being used commonly. Less studied is the prophylactic administration of antimuscarinics and IV fluids, despite the potential benefit of these measures and relatively low side-effect profile. We explore these topics here and offer advice for future research to fill the gaps in our knowledge.

Sialorrhea in Parkinson's Disease

Sialorrhea, or excessive saliva beyond the margin of the lip, is a common problem in many neurological diseases. Previously, sialorrhea has been underrecognized in Parkinson’s disease (PD) patients. Despite this, many patients rank sialorrhea as one of the most debilitating complaints of Parkinson’s disease. Previous treatment for sialorrhea has been suboptimal and has been plagued by significant side effects that are bothersome and can be dangerous in patients with a concurrent neurodegenerative disease. This review sought to review the anatomy, function, and etiology of sialorrhea in PD. It then sought to examine the evidence for the different treatments of sialorrhea in PD, and further examined newer evidence for safety and efficacy in minimally invasive treatment such as botulinum toxin.

Prevalence, risk factors, and optimized management of moderate-to-severe thirst in the post-anesthesia care unit

Post-operative thirst is common and may cause intense patient discomfort. The aims of this retrospective study conducted in a high-volume post-anesthesia care unit (PACU) were as follows: (1) to examine the prevalence of moderate-to-severe post-operative thirst—defined as a numerical rating scale (NRS) score of 4 or higher, (2) to identify the main risk factors for moderate-to-severe post-operative thirst, and (3) to maximize the efficacy and safety of thirst management through a quality improvement program. During a 1-month quality improvement program conducted in August 2018, a total of 1211 adult patients admitted to our PACU were examined. Moderate-to-severe thirst was identified in 675 cases (55.8%). The use of glycopyrrolate during anesthesia was associated with moderate-to-severe thirst (71.7% versus 66.4%, respectively, p = 0.047; adjusted odds ratio: 1.46, p = 0.013). Following a safety assessment, ice cubes, room temperature water, or an oral moisturizer were offered to patients. A generalized estimating equation model revealed that ice cubes were the most effective means for thirst management—resulting in an estimated thirst intensity reduction of 0.93 NRS points at each 15-min interval assessment (p < 0.001)—followed by room temperature water (− 0.92/time-point, p < 0.001) and the oral moisturizer (− 0.60/time-point; p < 0.001). Patient satisfaction (rated from 1 [definitely dissatisfied] to 5 [very satisfied]) followed a similar pattern (ice cubes: 4.22 ± 0.58; room temperature water: 4.08 ± 0.55; oral moisturizer: 3.90 ± 0.55, p < 0.001). The use of glycopyrrolate—an anticholinergic agent that reduces salivary secretion—was the main independent risk factor for moderate-to-severe post-operative thirst. Our findings may provide clues towards an optimized management of thirst in the immediate post-operative period.

Electro convulsive therapy: Modification of its effect on the autonomic nervous system using anti-cholinergic drugs

The antidepressant efficacy of electroconvulsive therapy (ECT) is correlated to the quality of the seizure as measured by EEG but has also been linked to the magnitude of changes in hemodynamic variables. Muscarinic receptor antagonists are frequently used in the treatment, and are known to affect the hemodynamic response. We hypothesized that atropine and glycopyrrolate alter the hemodynamic and autonomic hormonal response to ECT. In a randomized, cross-over study design 23 patients received either atropine, glycopyrrolate or placebo before ECT. Hemodynamic variable, EEG and EMG, and blood adrenaline, noradrenaline and pancreatic polypeptide was determined. No geriatric patients were included. Hemodynamic changes with ECT can be divided into three phases: Drop in blood pressure and pulse rate in 1st post-stimulus phase was less when using 1 mg atropine. In 2nd post-stimulus phase atropine gave a higher systolic blood pressure. No differences were seen in hormone levels after ECT in the three interventions. A significant longer tonic clonic seizure was seen in the glycopyrrolate group and a tendency of the same was seen with atropine. The study found that the changes in hemodynamic variables induced by ECT can be altered by concomitant administration of muscarinic receptor antagonist.

A multicentre evaluation of oropharyngeal secretion management practices in amyotrophic lateral sclerosis

Failure to clear oral secretions can be debilitating for patients with amyotrophic lateral sclerosis (ALS), but the treatment of this symptom is poorly defined and there is no consensus on best practice. The objective of this study was to identify the treatments that are commonly prescribed, and to describe how experienced clinicians manage a patient with treatment resistant symptoms. Twenty-three clinicians were approached, of which 19 from 16 centres across the UK provided case report forms for a total of 119 ALS patients identified as having problematic oral secretions. The use of five anticholinergics, salivary gland botulinum toxin injections, conservative management approaches and carbocisteine were reported. Of the 72 patients who were evaluated following the initiation of a first anticholinergic, 61% had symptomatic improvement. Only 19% of patients achieved symptomatic improvement with the use of an alternative anticholinergic when an initial anticholinergic achieved no symptomatic improvement. Problems with thick and thin secretions often coexisted, with 37% of patients receiving treatment for both types of problem. In conclusion, a variety of treatment options are employed by expert clinicians for problematic oral secretions in ALS patients. The variation in management highlights the need for further prospective research in this area.

Effects of intramuscular injection of glycopyrrolate on Schirmer tear test I results in dogs

OBJECTIVE To determine effects of glycopyrrolate administered IM on Schirmer tear test I (STT I) measurements in dogs. DESIGN Prospective clinical study. ANIMALS 13 client- and staff-owned dogs. PROCEDURES For both eyes of each dog, STT I measurements were recorded twice 20 minutes apart (at T1 and T2) and 2 to 4 hours later (at T3). Glycopyrrolate (0.01 mg/kg [0.005 mg/lb]) was administered IM to all dogs (3 dogs received an injection of saline [0.9% NaCl] solution on an earlier occasion), and final STT I measurements were recorded 20 minutes later (at T4). Intraocular pressures, heart rate, and respiratory rate were also recorded at each time point. RESULTS Ophthalmic variables did not differ between right and left eyes. In all dogs, variables at T1, T2, or T3 (measurements before glycopyrrolate administration) did not differ; baseline values were therefore defined at T3. At T4, STT I measurements were significantly decreased (mean ± SD decrease, 67.4 ± 15.4% [mean actual decrease, 15.8 mm/min]). During the same period, mean heart rate increased by 26.5 ± 12.0% (mean actual increase, 30.2 beats/min). Glycopyrrolate had no effect on intraocular pressure or respiratory rate. In 5 dogs at 24 hours after glycopyrrolate treatment, STT I measurement in each eye had returned to baseline value. Saline solution treatment (3 dogs) had no effect on any variables. CONCLUSIONS AND CLINICAL RELEVANCE In dogs, IM injection of glycopyrrolate resulted in a clinically relevant transient decrease in aqueous tear production. Application of lacrimomimetics beginning at the time of or within 20 minutes after glycopyrrolate premedication is recommended until STT I measurements return to baseline.

Equine piroplasmosis treatment protocols: specific effect on orocaecal transit time as measured by the lactose 13C-ureide breath test

REASONS FOR PERFORMING STUDY

Imidocarb dipropionate is the drug of choice for equine piroplasmosis but its administration causes severe colic and diarrhoea. An imidocarb protocol that reduces these effects is needed.

OBJECTIVES

1) Quantification of the effects of imidocarb dipropionate on equine orocaecal transit time (OCTT), with and without atropine or glycopyrrolate premedication and 2) investigation of an improved pretreatment regimen for imidocarb administration.

HYPOTHESIS

Treatment with imidocarb dipropionate will result in colic and reduced OCTT as demonstrated by the lactose 13C-ureide breath test which will be ameliorated by premedication with either atropine or glycopyrrolate.

METHODS

The effects of 3 drug therapies on OCTT were compared in 6 healthy horses in a randomised double-blind study vs. a saline control: 1) imidocarb dipropionate 2.4 mg/kg bwt administered intramuscularly (i.m.) with saline administered intravenously (i.v.; imidocarb/saline); 2) imidocarb dipropionate 2.4 mg/kg bwt administered i.m. with atropine 0.035 mg/kg bwt administered i.v. (imidocarb/atropine) and 3) imidocarb dipropionate 2.4 mg/kg bwt administered i.m. with glycopyrrolate 0.0025 mg/kg bwt administered i.v. (imidocarb/glycopyrrolate). The lactose 13C-ureide breath test was used to measure OCTT in each case and significance of treatment effect determined by a linear model analysis of variance.

RESULTS

Imidocarb/atropine treatment caused an increase in OCTT (P < 0.05) whereas imidocarb/saline produced a nonsignificant decrease in OCTT. Imidocarb/saline caused colic and diarrhoea in 4 of 6 horses, which were not seen in any of the horses treated with imidocarb/atropine or imidocarb/glycopyrrolate or administered the saline control. Intestinal borborygmi were increased in imidocarb/saline and decreased in imidocarb/atropine treated horses, respectively.

CONCLUSIONS

Imidocarb/saline treatment induced colic signs and a potential reduction in OCTT while imidocarb/atropine treatment increased OCTT significantly when compared with imidocarb/saline. Both atropine and glycopyrrolate premedication ameliorated the clinical gastrointestinal effects of imidocarb but atropine produced significant inhibition of gastric and/or small intestinal motility not detected with glycopyrrolate. Premedication with glycopyrrolate is recommended when using imidocarb for treatment of equine piroplasmosis.

Glycopyrrolate oral solution: for chronic, severe drooling in pediatric patients with neurologic conditions

Chronic drooling (sialorrhea) is a common dysfunction in children with neurologic disorders such as cerebral palsy. Glycopyrrolate oral solution, an anticholinergic agent, is the first drug treatment approved in the US for drooling in children with neurologic conditions. This article reviews the clinical efficacy and tolerability of glycopyrrolate oral solution in pediatric patients with neurologic conditions and provides an overview of the pharmacological properties of the drug. In a phase III, randomized, double-blind, multicenter trial, children (aged 3-16 years; n = 36) with problem drooling associated with neurologic conditions and receiving glycopyrrolate oral solution had a significantly (p < 0.01) greater modified Teacher's Drooling Scale (mTDS) response rate at 8 weeks (primary endpoint) than those receiving placebo (73.7% vs 17.6%). At 24 weeks in an additional, noncomparative, phase III study, 52.3% of glycopyrrolate oral solution recipients (aged 3-18 years; n = 137) had an mTDS response (primary endpoint); the response rate was consistently above 50% at all 4-weekly timepoints, aside from the first assessment at week 4 (40.3%). In general, glycopyrrolate oral solution was well tolerated in clinical trials. The majority of adverse events were within expectations as characteristic anticholinergic outcomes.

Glycopyrrolate for chronic drooling in children

BACKGROUND

Sialorrhea, or drooling, is seen in the pediatric population, especially in patients with cerebral palsy and other neurodevelopmental disabilities. If medication use is warranted, anticholinergic agents are the drug of choice; however, adverse effects limit their use. Glycopyrrolate, a synthetic anticholinergic that acts at peripheral muscarinic receptors, has been used off-label for excessive drooling in children with neurodevelopmental disabilities for years. Product formulations restricted the use of glycopyrrolate. However, an oral solution was approved by the US Food and Drug Administration for children ages 3 to 16 years with neurologic disorders for chronic severe drooling in 2010; it became available for use in 2011.

OBJECTIVE

This article provides an overview of the pharmacology, clinical efficacy, and tolerability of glycopyrrolate when used for sialorrhea in children.

METHODS

To evaluate the efficacy and safety profile of glycopyrrolate for the treatment of sialorrhea in children, a comprehensive search was performed of the MEDLINE database (1966-February 25, 2012) and International Pharmaceutical Abstracts as well as references from additional review articles identified. Searches were conducted using the terms glycopyrrolate, sialorrhea, drooling, secretion, and pediatrics. The terms drug-induced and Parkinson disease-associated sialorrhea were excluded from the search. The pharmaceutical manufacturer of the oral solution was contacted for medical and study information.

RESULTS

Oral bioavailability of glycopyrrolate varies widely, with a median of 3.3%. Mean C(max) in children was determined to be 0.37 μg/mL, and mean T(max) was 3.1 hours. The clearance in children ranges from 0.6 to 1.43 L/kg/h. The t(½) ranges from 22 to 130 minutes and 19 to 99 minutes in infants and children, respectively. Six studies describing the use of glycopyrrolate for drooling in children were identified. A double-blind, crossover trial of 27 patients (age range, 4-19 years) demonstrated a reduced mean drooling score (modified Teacher's Drooling Scale [1 = never drools to 9 = clothing, hands, and objects frequently become wet]) for glycopyrrolate (mean highest tolerated dose, 0.11 mg/kg) compared with placebo of 1.85 versus 6.33 (P < 0.001). In a parallel study of 36 patients (age range, 3-16 years), 14 of 20 patients randomized to receive glycopyrrolate solution showed improvement in the mean modified Teacher's Drooling Scale score compared with only 3 patients receiving placebo (-3.5 vs -0.1, respectively). Glycopyrrolate was initiated at 0.02 mg/kg per dose orally TID (Max dose: 3 mg) and titrated over a 4-week period. Adverse effects identified in studies include dry mouth (9%-41%), constipation (9%-39%), and behavioral changes (18%-36%).

CONCLUSIONS

Glycopyrrolate is effective in decreasing sialorrhea in children with cerebral palsy or other neurodevelopmental disabilities. Adverse effects did occur, more frequently at higher doses, and should be monitored.

The use of subcutaneous glycopyrrolate in the management of sialorrhoea and facilitating the use of non-invasive ventilation in amyotrophic lateral sclerosis

Sialorrhoea is a recognized complication of bulbar amyotrophic lateral sclerosis (ALS) that leads to an increased risk of potentially harmful aspiration and often prevents patients from tolerating non-invasive ventilation (NIV). A case of treatment-resistant sialorrhoea in bulbar ALS is described where subcutaneous glycopyrrolate was effective without significant side-effects. The patient went on to markedly increase the length of time she could tolerate NIV each night.

Sublingual atropine drops for the treatment of pediatric sialorrhea

Excess oral secretions or sialorrhea is a common problem affecting children and adults with neurological disorders, as well as those approaching the end of life because of a variety of underlying illnesses. Systemic anticholinergic medications are often prescribed in an attempt to improve quality of life and reduce complications; yet, response rates are variable, and a sizable proportion of patients discontinue these drugs as a result of intolerable side effects. This report describes the successful use of a local treatment, sublingually delivered ophthalmic atropine drops, to reduce sialorrhea in a child receiving palliative care. In addition, medical evidence for the safety and efficacy of traditionally prescribed systemic medications for the treatment of pediatric sialorrhea is reviewed.

Atropine, hyoscine butylbromide, or scopolamine are equally effective for the treatment of death rattle in terminal care

Death rattle is a frequent symptom (25%-50%) in the terminal stage of life, but there is neither standardized treatment nor prospective investigation performed on the effectiveness of anticholinergic drugs. The aim of the present study was to investigate the effectiveness of three different anticholinergic drugs in the treatment of death rattle in the terminal stage of life. Terminal patients who developed death rattle were randomly assigned 0.5mg atropine, 20mg hyoscine butylbromide, or 0.25mg scopolamine. Each treatment was initiated with a subcutaneous bolus, which was followed by continuous administration of the same drug. The intensity of death rattle and side effects were prospectively scored at different time points. Three hundred and thirty-three eligible patients were randomized to atropine, hyoscine butylbromide, or scopolamine after informed consent from the patient or the appointed representative. For the three drugs, death rattle decreased to a nondisturbing intensity or disappeared after one hour in 42%, 42%, and 37% of cases, respectively (P=0.72). Further, effectiveness improved over time without significant differences among the treatment groups (effectiveness at 24 hours was 76%, 60%, and 68%, respectively). In an analysis on the three groups together, treatment was more effective when started at a lower initial rattle intensity; median survival after start of therapy was 23.9 hours. These data suggest that there are no significant differences in effectiveness or survival time among atropine, hyoscine butylbromide, and scopolamine in the treatment of death rattle.

Using anti-muscarinic drugs in the management of death rattle: evidence-based guidelines for palliative care

The management of 'death rattle' was reviewed by a task group on behalf of the Association for Palliative Medicine's Science Committee. Evidence was searched for the effectiveness of various anti-muscarinic drugs in drying oropharyngeal and bronchial secretions in dying patients. Clinical guidelines were constructed based on evidence from volunteer and clinical studies. Death rattle occurs in half of all dying patients and some response occurs in around 80% of treated patients. Clinical studies demonstrate that subcutaneous hyoscine hydrobromide 400 microg is more effective at improving symptoms at 30 min than glycopyrronium 200 microg by the same route. Volunteer studies demonstrate that intramuscular glycopyrronium 400 microg is as effective in drying secretions at 30 min as a dose of 200 microg given intravenously. Duration of response is shortest for hyoscine butylbromide (1 h) and longest for glycopyrronium (more than 6 h). There is insufficient evidence to support the use of one drug over another in a continuous infusion and prescribers should base decisions on different characteristics of each anti-muscarinic drug.

A study comparing hyoscine hydrobromide and glycopyrrolate in the treatment of death rattle

This study looked at the efficacy of drug treatment in managing death rattle in a 30-bedded specialist palliative care unit. The study was conducted in two phases. In the first, patients received hyoscine hydrobromide as the antimuscarinic; glycopyrrolate was used in the second phase. The patients in the two phases were well matched for diagnosis, age, sex and duration of death rattle. A noise score scale of 0-3 was used, which was separately validated using a verbal rating scale and noise-meter readings. Noise scores were taken at the start; 30 min after an antimuscarinic drug was administered; an hour after the initial injection if a repeat dose was given at 30 min; and 4-hourly thereafter. Drug charts of all patients with death rattle were analysed to ascertain the amount of each drug given and the cost. The incidence of death rattle was 44% in phase I, and 36% in phase II. The percentage of patients with reduced noise scores 30 min after one injection of hyoscine was significantly greater than after one dose of glycopyrrolate (56% vs 27%, P = 0.002). The need for a second injection after 30 min was less using hyoscine (33% vs 50%, P = 0.03). There was no statistically significant difference in improvement at 1 h, or at the last recorded score before death. A comparison of the cost of drug treatment using hyoscine or glycopyrrolate was made, and the potential reduction in cost per patient in the glycopyrrolate group was largely offset by increased expenditure on other drugs, especially diamorphine, midazolam and levomepromazine. The results of this study suggest that: (1) glycopyrrolate 0.2 mg is less effective at reducing death rattle than hyoscine hydrobromide 0.4 mg when assessed at 30 min, (2) the use of glycopyrrolate may lead to an increased need for other sedative or anti-emetic medication such as diamorphine, midazolam or levomepromazine, and (3) the cost benefit of using glycopyrrolate over hyoscine hydrobromide is a small part of the total drug budget, and may be less than anticipated due to the increased need of these other drugs.

The effects of glycopyrrolate on oral mucous host defenses in healthy volunteers

We studied the effects of glycopyrrolate on oral mucous host defenses. Single IV doses of glycopyrrolate (4 microg/kg) or placebo were administered to 12 healthy volunteers in a randomized, double-blinded, cross-over study. Salivary flow rates and the concentrations/activities of total protein, amylase, and nonimmunologic (lysozyme, lactoferrin, myeloperoxidase, total salivary peroxidase, and thiocyanate) and immunologic (total immunoglobulin A, immunoglobulin G, and immunoglobulin M) mucous host defense factors were determined for paraffin-stimulated whole saliva before and 1, 3, 6, 12, 24, and 48 h after drug administration. Glycopyrrolate serum concentrations were determined before and 2, 4, 6, 10, 15, and 30 min and 1, 2, 3, 6, 12, and 24 h after IV drug injection. Salivary flow rates were decreased significantly for 12 h after glycopyrrolate injection, compared with saline injection. The concentrations of immunologic and nonimmunologic defense factors were increased in the glycopyrrolate group, and differences between the groups were found for all factors (P < 0.05-0.001) except lysozyme and total salivary peroxidase. In contrast, because of the reduced flow rate, the output of all defense factors into the saliva was decreased after glycopyrrolate injection, compared with saline injection. Glycopyrrolate thus decreases the output of salivary host defense factors into the oral cavity.

IMPLICATIONS

Glycopyrrolate induces long-lasting hyposalivation and decreases the secretion of salivary immunologic and nonimmunologic defense factors in healthy volunteers.

Oral glycopyrrolate alleviates drooling in a patient with tongue cancer

Although sialorrhea and drooling are uncommon symptoms in cancer patients, they can cause considerable discomfort, inconvenience and social embarrassment. In this article we describe a patient with tongue cancer who was successfully treated with oral glycopyrrolate 0.4 mg 3 times daily. Glycopyrrolate is a quaternary ammonium compound. In contrast to the recommended treatment with scopolamine, glycopyrrolate is virtually without side effects to the central nervous system because it penetrates the blood-brain barrier poorly. Glycopyrrolate has a slow and erratic absorption from the gastrointestinal system, but even low plasma levels are associated with a distinct and long-lasting antisialogic effect.

Preliminary study of glycopyrrolate in the management of drooling

OBJECTIVE

A study was undertaken to assess the efficacy of an oral anticholinergic drug, glycopyrrolate, in the management of drooling in children and young adults with disabilities.

METHODOLOGY

Glycopyrrolate was used by 24 children and young adults for up to 28 months. Parents/carers were asked to complete a questionnaire on the effects of the drug on severity and frequency of drooling and to report any side-effects.

RESULTS

Twenty-two questionnaires were returned. There was a statistically significant decrease in both severity and frequency of drooling with minimal side-effects reported.

CONCLUSION

In this preliminary study, glycopyrrolate was found to be an effective and well-tolerated addition to the management of drooling in children with disabilities.

Anticholinergics improve fibreoptic intubating conditions during general anaesthesia

PURPOSE

To determine if anticholinergic agents improve fibreoptic intubating conditions and to compare the efficacy and side effects of glycopyrrolate and hyoscine.

METHODS

Eighty ASA I adults undergoing elective wisdom tooth extraction were randomly allocated to receive 0.4 mg hyoscine hydrobromide po, 0.4 mg hyoscine hydrobromide im, 0.4 mg glycopyrrolate im or no anticholinergic, one hour pre-operatively. All underwent nasal fibreoptic intubation under general anaesthesia. The time taken to pass the fibreoptic scope was noted and visual analogue scores (VAS) were recorded for clarity of visual field and post-operative sore throat, dry mouth and nausea.

RESULTS

The time to intubation was not different among the four groups (Kruschal-Wallis P = 0.07). The clarity of visual field was improved in all three anticholinergic groups (Kruschal-Wallis P = 0.006), but there was no difference among the three groups (median VAS control 6.4, glycopyrrolate 8.0, oral hyoscine 7.9, im hyoscine 7.7). There was no difference in post-operative side effects among any of the groups at both 30 min and four hours.

CONCLUSION

The addition of an anticholinergic produced better visual conditions for intubation but had no effect on the incidence of post-operative sore throat, dry mouth and nausea.

Death rattle: an audit of hyoscine (scopolamine) use and review of management

This study investigated the pattern and determinants of hyoscine (scopolamine) use for death rattle by a retrospective analysis of 100 consecutive deaths in a 22-bed hospice. Patient diagnoses, duration of stay, and doses and route of administration of hyoscine used in the final 48 hr before death were recorded. One-half of the patients received hyoscine in some form during the final 24 hr before death. Patients who were in the hospice for longer than 9 days and those with cerebral malignancy were given the highest doses of hyoscine in the final 24 hr (z = -2.558, P = 0.011, and z = -1.968, P = 0.048, respectively). Response to hyoscine appears to be variable, and a distinction is proposed between death while due to salivary secretions (type 1) and that due to bronchial secretions (type 2) to explain the observed patterns of use. It is likely that hyoscine is more efficacious in treating type 1 death rattle than it is in treating type 2 death rattle.

The mydriatic effect of topical glycopyrrolate

BACKGROUND

Glycopyrrolate, an anticholinergic agent that does not cross the blood-brain barrier, has several indications, but its mydriatic effect has never been tested. This study was carried out in order to compare the mydriatic effect of glycopyrrolate 0.5% to that of atropine sulfate 1%.

METHODS

Glycopyrrolate 0.5% and atropine 1.0% were instilled separately in the eyes of albino rabbits. Pupil diameter and intra-ocular pressure were monitored.

RESULTS

Mydriasis was noted within 5 min of glycopyrrolate instillation, reached near-maximal level at 15 min and persisted for 1 week. Glycopyrrolate 0.5% showed a faster, stronger and more persistent mydriatic effect than atropine 1.0%. Administration of glycopyrrolate 0.5% solution b.i.d. for 1 week did not affect intra-ocular pressure or produce any adverse reaction.

CONCLUSION

Glycopyrrolate solution has the potential to deliver an ocular anticholinergic effect without causing associated central anticholinergic hazards.

Glycopyrrolate vs. atropine during anaesthesia for laryngoscopy and bronchoscopy

As glycopyrrolate has been reported superior to atropine with respect to reduction of salivation, stability of cardiac rate and rhythm, and recovery, a comparison of these properties of the two drugs and placebo was made in 45 patients undergoing direct laryngoscopy and 45 patients undergoing bronchoscopy, in most cases followed by mediastinoscopy. When given i.m. 30 min before anesthesia (midazolam, alfentanil, thiopentone, and suxamethonium), the two test drugs were found to be equally potent regarding the antisialogogic effect. The same increase in heart rate after the test drugs was seen before induction, and during anaesthesia heart rate rose to the same level in the placebo group as the test groups. During anaesthesia, blood pressure was lowest in the atropine group. No differences could be demonstrated with respect to cardiac arrhythmias, possibly due to the small size of the material. The present study gives no reason for preferring either drug, and only the efficacy of both test drugs in controlling airway secretions provides an argument for using any anticholinergic drug when laryngoscopy or bronchoscopy is performed under the conditions of the present study.

Twelve-hour bronchodilation in asthma with a single aerosol dose of the anticholinergic compound glycopyrrolate

Anticholinergic aerosols provide effective bronchodilation in some patients with obstructive lung disease. Glycopyrrolate is a quaternary ammonium anticholinergic compound that is poorly absorbed from mucus membranes, thus reducing anticholinergic side effects. In 20 adult patients with asthma, we evaluated bronchodilation to a single administration of metered-dose glycopyrrolate aerosol (GA) to ascertain its onset and duration of action along with evaluation of safety. In this randomized, double-blind, placebo-controlled, single-dose, crossover trial, bronchodilation was evaluated on five separate occasions to either placebo or a GA dose of 80, 240, 480, or 960 micrograms. Baseline spirometry for each patient on each visit was similar (mean FEV1 +/- SD of 62.2 +/- 13.6% predicted). After aerosol dosing, spirometry was measured at 30 minutes and then at hourly intervals up to 12 hours. Compared to placebo, metered-dose aerosols of 240, 480 and 960 micrograms elicited significantly greater bronchodilation at each test time. Furthermore, significant bronchodilation was noted within 30 minutes of dosing and was sustained for at least 12 hours. Bronchodilation with the 480 and 960 micrograms dose was equal, and both were greater than 240 micrograms. A subset of four asthma patients with baseline FEV1 values less than 50% predicted did not have a bronchodilating response with GA. No notable side effects occurred. Thus, a single aerosol dose of GA provides clinically significant, safe 12-hour bronchodilation in patients with asthma without severe airway obstruction (i.e., FEV1 greater than 50% predicted).

Oral scopolamine hydrobromide solution as an antisialagogic agent in dentistry

Antisialagogue, cardiac, and subjective effects of oral scopolamine hydrobromide solution (ScHBr), 0.02 mg/kg total body weight, were studied in a double-blind, randomized, placebo-controlled manner with ten healthy volunteers. ScHBr was rinsed in the mouth for 5 minutes before swallowing. ScHBr reduced nonstimulated and paraffin-stimulated salivation at 40 minutes by 52% and 62%, and at 60 minutes by 81% to 80%, respectively. The heart rate decreased significantly (p less than 0.01) when compared with placebo. With the same drug dosing method, the effects of ScHBr also were tested in clinical dental examination procedures in two dental student groups. In the ScHBr group, salivation decreased by 70%, and in the placebo group, it increased by 22% as a result of mechanical stimulus. Subjective sedation and relaxation were experienced by most of the volunteers.

Effect of glycopyrrolate and atropine on thermoregulation after exercise

The effects of two anticholinergic drugs on heat production (derived from oxygen consumption), sweating and core and skin temperature were compared with saline placebo in five healthy volunteers, before and after exercise. There were no significant differences between the groups in resting and peak heat production after exercise. Sweat evaporation rate increased after exercise in all cases, but there was individual variation in response to the drugs. Sweat evaporation was greater after saline placebo compared with atropine, but not after glycopyrrolate compared with saline placebo or atropine. In the saline placebo group, increased sweat evaporation following exercise was reflected by an initial fall, in skin temperature. Following anticholinergic drugs, skin temperature increased after exercise without an initial decrease. Core temperature increased following exercise, but there were no significant differences between the anticholinergic drugs and saline placebo. Although clinical doses of anticholinergic drugs, when compared with saline placebo, inhibited sweating after exercise, core temperature was not significantly increased. Therefore it is suggested that non-evaporative heat loss compensated for the reduction in sweating due to anticholinergic drugs.

Glycopyrrolate during ketamine/diazepam anaesthesia. A double-blind comparison with atropine

In a double-blind study, the effects of atropine and glycopyrrolate (dosage ratio 2:1) following i.m. and i.v. administration were compared with respect to salivation, heart rate, and blood pressure before, during and after i.v. infusion anaesthesia with ketamine and diazepam for alloplastic hip or knee surgery in 30 patients above the age of 50 years. Given with the premedicant, the two drugs were equally effective in reducing salivation. A slight increase in heart rate was seen after atropine only (P less than 0.005). Increases in heart rate and blood pressure during induction of anaesthesia were similar in the two groups. A second dose of the test drug was given with neostigmine for reversal of neuromuscular blockade. Again, there were no statistically significant differences with respect to salivation, blood pressure, heart rate, nausea and/or vomiting, unpleasant dreams and arousal time.

Atropine or glycopyrrolate with neostigmine 5 mg: a comparative dose-response study

One hundred and fifteen patients, separated into 4 groups, received neostigmine 5 mg with either atropine 1.2 mg or 1.8 mg, or glycopyrrolate 0.6 mg or 0.9 mg. Those receiving 0.9 mg glycopyrrolate had insignificant changes in heart rate in the immediate postreversal period. It is recommended that when glycopyrrolate is used with 5 mg neostigmine, the optimum dose is 0.9 mg.

The effects of atropine and glycopyrrolate on intra-ocular pressure in anaesthetised elderly patients

The effects of glycopyrrolate 0.2 mg and atropine 0.6 mg, given intravenously, were studied in 40 elderly patients undergoing intra-ocular surgery. Twenty patients had normal intra-ocular pressure (IOP) and 20 had raised IOP. The effects of each of the drugs on IOP, heart rate, prevention of the oculocardiac reflex and incidence of dysrhythmias were assessed. Anaesthesia with thiopentone, suxamethonium, nitrous oxide/oxygen, and halothane, using a semiclosed circle system resulted in a decrease in mean IOP in both the atropine and glycopyrrolate groups. Patients who had pre-existing raised IOP showed a significantly greater decrease in IOP than those with normal IOP. Patients with raised IOP who had received atropine experienced a greater decrease in IOP than those who had received glycopyrrolate. Both atropine and glycopyrrolate were effective in preventing the oculocardiac reflex. The increase in heart rate was greater in those patients who had received atropine. The incidence of dysrhythmias was low.

Effect of inhaled glycopyrrolate and atropine in asthma. Precipitated by exercise and cold air inhalation

We compared the effects of inhaled glycopyrrolate (G), 1.3 mg, and atropine (A), 2.6 mg, and placebo on FEV1 and specific conductance (sGaw) before and after exercise in six men with exercise-induced asthma. Subjects exercised with cold air (-2 degrees C) 30 and 120 minutes after each aerosol treatment. Spirometry was performed and sGaw determined before aerosol treatment (baseline) and before and after exercise. Decreased airway tone was noted before exercising with A and G but not with placebo. The decreases in FEV1 and sGaw resulting from exercise were not significantly different among the three treatment groups at either exercise session. Postexercise FEV1 and sGaw were significantly higher after A and G compared to P. Dry mouth, flushing, and resting tachycardia were prominent with group A. Symptoms in G did not differ from those in P. This study suggests that A and G do not prevent bronchoconstriction induced by exercise and cold air but improve postexercise pulmonary function by achieving preexercise bronchodilation. Systemic side effects were minimal with G compared to A.

Glycopyrrolate: pharmacology and clinical use

This is a review of glycopyrrolate whose function in clinical practice is compared with that of atropine.