Pharmacokinetics of glycopyrronium in uraemic patients

Palliative care for children and young people with stage 5 chronic kidney disease

Death from stage 5 chronic kidney disease (CKD 5) in childhood or adolescence is rare, but something that all paediatric renal physicians and most paediatricians will encounter. In this paper, we present the literature on three key areas of palliative care practice essential to good clinical management: shared decision-making, advance care planning, and symptom management, with particular reference to CKD 5 where kidney transplant is not an option and where a decision has been made to withdraw or withhold dialysis. Some areas of care, particularly with regard to symptom management, have not been well-studied in children and young people (CYP) with CKD 5 and recommendations with regard to drug choice and dose modification are based on adult literature, known pharmacokinetics, and clinical experience.

The Role of Opioids in Pain Management in Elderly Patients with Chronic Kidney Disease: A Review Article

Chronic kidney disease (CKD) is a global public health problem. Pain is one of the most generally experienced symptoms by CKD patients. Pain management is a key clinical activity; nonetheless, insufficient pain management by health professionals keeps it up. Opioids as pain relievers are a class of naturally-derived and synthetic medications. They act through interactions with receptors in peripheral nerves. Numerous pharmacokinetic alterations happen with aging that influence drug disposition, metabolism, and quality of life. Acetaminophen alone, or combined with low-potency opioid dose is regarded as the safest pain-relieving choice for CKD. Morphine and codeine are probably eluded in renal impairment patients and used with excessive carefulness. Tramadol, oxycodone, and hydromorphone can be used by patient monitoring, while methadone, transdermal fentanyl, and buprenorphine seem to be safe to use in older non-dialysis patients with renal impairment. Consistent with the available literature, the main aim of this review was to explore the occurrence of chronic pain and its opioid treatment in CKD patients. According to this review, more and well-made randomized controlled trials are necessary to find appropriate opioid doses and explore the occurrence of side effects.

Physiologically Based Pharmacokinetic Modelling of Glycopyrronium in Patients With Renal Impairment

Glycopyrronium bromide, a synthetic anticholinergic agent used to treat patients with chronic obstructive pulmonary disease (COPD), is eliminated from the body by renal excretion and therefore systemic exposure is expected to be increased in patients with decreasing renal function. Despite enrollment of patients with decreasing renal function to evaluate the impact of renal impairment on the pharmacokinetics of glycopyrronium in clinical studies, no patients with severe renal impairment were included. A physiologically based pharmacokinetic (PBPK) model was developed in patients with COPD with normal renal function and used to predict systemic exposure of glycopyrronium in patients with severe renal impairment. The model accurately predicted plasma concentration-time profiles in patients with normal renal function, and mild and moderate renal impairment; the predicted and observed AUC and C_max in these populations were similar. Compared to patients with normal renal function, a 1.20-, 1.45-, and 1.59-fold increase AUC was predicted in patients with mild, moderate, and severe renal impairment, respectively, suggesting dose adjustment is not necessary in patients with renal impairment. In conclusion, PBPK models, verified with clinical study data from patients with normal renal function, can potentially be used to predict the pharmacokinetics and recommended dose adjustment for patients with renal impairment.

Pharmacology, toxicology and clinical safety of glycopyrrolate

The clinical use of the anticholinergic glycopyrrolate dates back to the early 1960s when it was first approved in the U.S. Since then, oral and inhalation formulations have been developed as therapeutic agents inhibiting the muscarinic acetylcholine receptor in various indications including chronic obstructive pulmonary disease (COPD), excessive salivation, and peptic ulcers. More recently, topical formulations of glycopyrrolate (GPB, also known as glycopyrronium bromide) have gained interest as a treatment option for excessive sweating (hyperhidrosis). The U.S. Food and Drug Administration (FDA) approved the first topical glycopyrronium product for the treatment of hyperhidrosis in 2018. Glycopyrrolate, as a quaternary amine, shows minimal penetration of the blood brain barrier which limits CNS side effects. In addition, lack of phototoxicity, genotoxicity and carcinogenicity makes it suitable for chronic indications. The information on the nonclinical and clinical safety profile of glycopyrronium supporting various therapeutically approved uses has been obtained from published literature, our own data as well as summary documents issued by regulatory bodies. Collectively, these data support the conclusion that the benefits of glycopyrronium generally outweigh the risks in chronic use indications that require muscarinic receptor antagonism to provide therapeutic effects.

Anticholinergics in palliative medicine: an update

Anticholinergics, or antimuscarinic drugs, are drugs that competitively inhibit the action of acetylcholine at muscarinic receptors, leading to a blockade of the actions of the parasympathetic nervous system at sites where overactivity can lead to increased symptom burden. Successful blockade of the parasympathetic nervous system ultimately leads to decreased production of secretions in the salivary, bronchial, and gastrointestinal tracts. These effects are often used for several symptoms that originate due to parasympathetic nervous system overactivity, such as the "death rattle" and malignant bowel obstruction. Anticholinergic agents are divided into either tertiary amines or quaternary ammonium compounds, which differ in their ability to cross into the central nervous system. Quaternary compounds do not cross into the central nervous system and have a different adverse effect profile than the tertiary amines. The purpose of this review is to highlight anticholinergic agents, their pharmacology, and an evidence-based assessment of their role in palliative care.

Dialysability of sugammadex and its complex with rocuronium in intensive care patients with severe renal impairment

BACKGROUND

Renal excretion is the primary route for the elimination of sugammadex. We evaluated the dialysability of sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment in the intensive care unit (ICU).

METHODS

Six patients in the ICU with acute severe renal impairment received general anaesthesia for transoesophageal echocardiography, to replace their tracheal tubes, or for bronchoscopy. Five of the six patients were in the ICU after cardiac/vascular surgery and one for pneumonia-induced respiratory failure. They all received rocuronium 0.6 mg kg(-1), followed 15 min later by sugammadex 4.0 mg kg(-1). Two patients were studied for two dialysis episodes and four patients for four episodes. Rocuronium and sugammadex concentrations were measured in plasma and dialysate at several time points before, during, and after high-flux dialysis. Dialysis clearance in plasma and dialysate, and reduction ratio (RR) (the extent of the plasma concentration reduction at the end of a dialysis episode when compared with before dialysis) were calculated for each dialysis episode.

RESULTS

Dialysis episodes lasted on average 6 h. Observed RRs indicated mean reductions of 69% and 75% in the plasma concentrations of sugammadex and rocuronium, respectively, during the first dialysis episode. Reductions were around 50% during sequential dialysis episodes. On average, dialysis clearance of sugammadex and rocuronium in blood was 78 and 89 ml min(-1), respectively.

CONCLUSIONS

Haemodialysis using a high-flux dialysis method is effective in removing sugammadex and the sugammadex-rocuronium complex in patients with severe renal impairment.

Synthesis and pharmacological effects of new, N-substituted soft anticholinergics based on glycopyrrolate

To reduce the possibility of systemic side-effects in locally administered anticholinergics, two new N-substituted glycopyrrolate analogues designed using soft drug design approaches have been synthesized and evaluated in vitro and in vivo. Because stereospecificity is known to be important at muscarinic receptors, the new compounds SGM and SGE also have been prepared as their pure 2R isomers, 2R-SGM and 2R-SGE, by starting from optically pure (-)-cyclopentylmandelic acid, and the corresponding isomers were indeed found to be more active. The new soft glycopyrrolates were chemically more stable under acidic conditions, and the ethyl esters SGE were more stable than the methyl esters SGM. The new compounds were also found to be quite susceptible to extrahepatic metabolism, having half-lives of 20–30 min in rat plasma (in vitro), consistent with their soft nature. Binding studies at human muscarinic receptors (M1−M4) and guinea-pig ileum assays found 2R-SGM and 2R-SGE to have potencies somewhat less than, but close to, those of glycopyrrolate and N-methylscopolamine. They caused pupil dilation in rabbit eyes, but their mydriatic effects lasted for considerably less time than that of glycopyrrolate, and they did not induce dilation of the pupil in the contralateral, water-treated eyes, indicating that, in agreement with their soft nature, they are locally active, but safe and with a low potential to cause systemic side-effects.

Symptom management for the adult patient dying with advanced chronic kidney disease: a review of the literature and development of evidence-based guidelines by a United Kingdom Expert Consensus Group

Improvement in end-of-life-care is required for patients dying with chronic kidney disease (CKD). The UK government now recommends that tools such as the Liverpool Care Pathway for the Dying Patient (LCP) be used to enhance the care of those patients dying with CKD. The LCP was originally developed for patients dying with terminal cancer, however has been shown to be transferable to patients dying with heart failure or stroke. On this background, in 2005 a UK National Renal LCP Steering Group was formed. The aim was to determine whether or not the generic LCP was transferable to patients dying with CKD. An Expert Consensus sub-group was established to produce evidence-based prescribing guidelines to allow safe and effective symptom control for patients dying with renal failure. These guidelines were finalised by the Expert Consensus group in August 2007 and endorsed by the Department of Health in March 2008. A literature search on symptom control and end-of-life care in renal failure was performed. A summary of the evidence was presented at a National Steering Group meeting. Opinions were given and provisional guidelines discussed. A first draft was produced and individually reviewed by all members of the Expert Group. Following review, amendments were made and a second draft written. This was presented to the entire National Steering Group and again individual comments were taken into consideration. A third and fourth draft were written and individually reviewed, before the guidelines were finalised by the Expert Consensus group. Patients dying with advanced CKD suffer symptoms similar to patients dying of cancer. The Renal LCP prescribing guidelines aim to control the same symptoms as the generic LCP: pain, dyspnoea, terminal restlessness and agitation, nausea and respiratory tract secretions. The evidence for the production of the guidelines is discussed and how a consensus was reached. A summary of the guidelines is given and the complete guidelines document is available via the Marie Curie Palliative Care Institute, Liverpool website.

Anaesthesia for renal transplant surgery

Renal transplantation is the preferred therapeutic option for patients with end-stage renal disease. Survival rates are much higher in patients who receive a transplant. Patients with renal failure have significant concomitant medical conditions, such as cardiovascular disease. This article provides an overview of the important issues to be considered in patients undergoing renal transplant, and discusses the anaesthetic management of these patients.

Pharmacokinetic and Pharmacodynamic Evaluations of the Zwitterionic Metabolite of a New Series of N-Substituted Soft Anticholinergics

PURPOSE

This study was conducted to evaluate the zwitterionic common metabolite of a novel series of N-substituted soft analogs of glycopyrrolate both as racemates and as 2R isomers.

METHODS

Activities were assessed using both in vitro (receptor binding assay, guinea pig ileum pA2 assay) and in vivo techniques (rabbit mydriatic response, rat cardiac effects). Pharmacokinetic characterizations in rats were also performed.

RESULTS

The metabolite was highly water-soluble and very stable in buffer solutions as well as in rat biological media. Following i.v. administration in rats, it was very rapidly eliminated, mainly through renal excretion with a half-life of about 10 min. Receptor binding and guinea pig ileum assays indicated this metabolite as more than 1 order of magnitude less active than its parent soft drugs or glycopyrrolate. Moderate M3/M2 muscarinic receptor subtype selectivity was observed, further reducing the likelihood of cardiac side effects. The metabolite showed to some extent mydriatic effect and protective effect against carbachol-induced bradycardia, but of much shorter durations than glycopyrrolate; it had, however, no effect on resting heart rate.

CONCLUSIONS

N-Substituted zwitterionic metabolites retain some, but only considerably reduced activity of their parent quaternary ammonium ester soft anticholinergic drugs, and they are very rapidly eliminated from the systemic circulation. They are suitable for their assigned role within the framework of inactive metabolite-based soft anticholinergic design.

Pharmacokinetics and oral bioavailability of glycopyrrolate in children

Based on plasma levels determined with a radioreceptor assay and following a single oral (50 micrograms/kg) and intravenous (5 micrograms/kg) administration of glycopyrrolate in six healthy children operated twice during a several weeks period, a negligible and variable oral bioavailability was found (3.3; 1.3-13.3%) (median;range). No significant changes in heart rate after oral or intravenous administration of the drug could be seen. Oral glycopyrrolate appears to have no place in paediatric premedication.

Heart rate variability in diabetic and non-diabetic renal transplant patients

BACKGROUND

Heart rate variability (HRV) has been used to investigate the autonomic modulation of heart rate. Diminished HRV has been observed in diabetic autonomic neuropathy, a condition associated with increased mortality. Uraemia is associated with impaired autonomic function, but reports on the effects of uraemia on HRV are scarce.

METHODS

HRV and its circadian variation were studied in 12 diabetic and 11 non-diabetic renal transplantation and in 12 control patients. HRV in time and frequency domains was determined from 24-hour ECG recordings.

RESULTS

In the diabetic group, all time domain and frequency domain measures of HRV were markedly reduced (P < 0.05), when compared with the control group, and the circadian variation of HRV was absent. The mean (SD) amplitudes (ms) in the frequency bands were: high frequency: 3 (1), 6 (3) and 15 (3); low frequency: 9 (7), 16 (10) and 25 (8); very low frequency: 14 (8), 23 (12) and 30 (11) in the diabetic and non-diabetic uraemic and in the control patients, respectively. In non-diabetic uraemic patients, a tendency to reduced HRV was observed, but no statistical differences in HRV measures were found when compared with the control group.

CONCLUSION

The severe impairment of HRV in patients with end-stage diabetic nephropathy is probably due to autonomic neuropathy and partly also to the co-existing heart diseases. It may be a contributing risk factor for ventricular arrhythmias and sudden death in these patients. Uraemia alone causes similar but less severe changes in HRV.

Pharmacokinetics of glycopyrrolate in children

STUDY OBJECTIVE

To investigate the pharmacokinetics of glycopyrrolate in children.

DESIGN

Open study with three parallel groups.

SETTING

Pediatric surgery department at a university hospital.

PATIENTS

26 healthy ASA physical status I children undergoing minor surgery.

INTERVENTIONS

Patients were assigned to 1 of 3 groups: under 1 year of age (Group 1, n = 8), between 1 and 3 years of age (Group 2, n = 7), and over 3 years of age (Group 3, n = 11). Glycopyrrolate 5 micrograms/kg was given as a single intravenous (i.v.) injection before induction of general anesthesia. Blood samples (for determination of drug concentrations in plasma) were collected via venous cannula inserted into the contralateral antecubital vein.

MEASUREMENTS AND MAIN RESULTS

ECG was observed continuously, blood pressure was measured with an automatic noninvasive device, and blood samples were taken just before and at 2, 4, 6, 10, 15, 30, 60, 120, 180, 240, 360, and 480 minutes after injection of glycopyrrolate. Glycopyrrolate concentrations in plasma were determined with a radioreceptor assay. The only significant difference in the pharmacokinetic parameters was the shortened elimination half-life in patients between 1 and 3 years of age. Glycopyrrolate 5 micrograms/kg i.v. did not cause any significant alterations in heart rate.

CONCLUSIONS

There were no significant changes in the distribution volume or clearance of glycopyrrolate in children of different ages. The shortened elimination half-life in children between 1 and 3 years of age is of minor clinical importance.