Effects of intravenous administration of glycopyrrolate and atropine in anaesthetised patients

A Rare Case of Drug Interaction Presenting as Perioperative Hyperthermia in a Patient Presenting for Neurosurgery

Perioperative hyperthermia has many differential diagnoses. This case report describes the rare causation of perioperative hyperthermia in a patient presenting for epilepsy surgery. The patient had two episodes of hyperthermia, initially post-anesthetic induction and later in the immediate post-operative period. The quest for the etiology sheds light on a rare drug interaction between topiramate, an antiepileptic drug, and glycopyrrolate causing intraoperative hyperthermia. However, the literature has not reported drug interaction between topiramate and glycopyrrolate resulting in perioperative hyperthermia. The combination of a glycopyrrolate-induced rise in temperature and oligohidrosis could have resulted in hyperthermia in our patient. Thus, it is prudent to avoid glycopyrrolate in the perioperative period when patients are on topiramate.

Atropine use may lead to post-operative respiratory acidosis in neonates receiving ductal ligation: A retrospective cohort study

BACKGROUND

Patent ductus arteriosus (PDA) is one of the most common cardiac conditions in preterm infants. Closure of the PDA in symptomatic patients can be achieved medically or surgically. Atropine is commonly administered in general anesthesia as a premedication in this age group but with limited evidence addressing the effect of its use. Our study examined the association of the use of atropine as a premedication in PDA ligation and the risk of post-operative respiratory complications.

METHODS

This retrospective cohort study included 150 newborns who have failed medical treatment for PDA and received PDA ligation during 2008-2012 in a single tertiary medical center. Ninety-two of them (61.3%) received atropine as premedication for general anesthesia while 58 (38.7%) did not. Post-operative respiratory condition, the need of cardiopulmonary resuscitation and the presence of bradycardia were measured.

RESULTS

Patients with atropine use were associated with increased odds of respiratory acidosis in both univariate analysis (22.9% vs 7.3%; OR = 3.785, 95% CI = 1.211-11.826, p = 0.022) and multivariate analysis (OR = 4.030, 95% CI = 1.230-13.202, p = 0.021), with an even higher odds of respiratory acidosis in patients receiving both atropine and ketamine.

CONCLUSION

The use of atropine as premedication in general anesthesia for neonatal PDA ligation is associated with higher risk of respiratory acidosis, which worsens with the combined use of ketamine.

Intravenous Glycopyrrolate and Atropine at Induction of Anaesthesia: A Comparison1

In unpremedicated patients presenting for general anaesthesia for electroconvulsive therapy (ECT), the use of atropine combined with methohexitone as an intravenous induction agent was found to produce a significantly greater increase in heart rate than glycopyrrolate in similar combination. There was no difference in the antisialogogue effect of the two drugs at the doses used, and both drugs provided similar protection against the effects of suxamethonium and ECT on heart rate.

Reversal of rocuronium-induced neuromuscular blockade with sugammadex compared with neostigmine during sevoflurane anaesthesia: results of a randomised, controlled trial

BACKGROUND AND OBJECTIVE

Sugammadex, a modified gamma-cyclodextrin, is a selective relaxant-binding agent designed to reverse the effects of the steroidal neuromuscular blocking agents rocuronium or vecuronium. This study compared the efficacy of sugammadex and neostigmine for reversal of neuromuscular blockade induced by rocuronium for facilitating elective surgery.

METHODS

This randomised, multicentre, parallel-group trial included 98 adult patients. Patients received intravenous propofol for induction followed by sevoflurane maintenance anaesthesia. Neuromuscular blockade was monitored using acceleromyography and a train-of-four (TOF) mode of stimulation. Patients were randomly allocated to receive sugammadex 2.0 mg kg(-1) or neostigmine 50 microg kg (-1) (with glycopyrrolate 10 microg kg(-1)) at reappearance of the second response of the TOF (mean 16% twitch height of first response) after the last dose of rocuronium. Safety was evaluated by assessing adverse events, laboratory variables and vital signs.

RESULTS

Time to recovery of the TOF ratio of 0.9 after sugammadex compared with neostigmine was significantly shorter (P < 0.0001), being 1.5 versus 18.6 min (geometric means). Predictability of response was greater with sugammadex than neostigmine: with 98% of sugammadex patients versus 11% of neostigmine patients recovering to a TOF ratio of 0.9 within 5 min. There were no clinical events related to residual neuromuscular blockade or reoccurrence of blockade. Serious adverse events were observed in two sugammadex-treated patients and in three neostigmine-treated patients, respectively, but none were considered related to study drugs.

CONCLUSION

Sugammadex achieved significantly faster recovery of neuromuscular function after rocuronium to a TOF ratio of 0.9 compared with neostigmine (Clinicaltrials.gov identifier: NCT00451217).

Local heating of human skin causes hyperemia without mediation by muscarinic cholinergic receptors or prostanoids

Local changes in surface temperature have a powerful influence on the perfusion of human skin. Heating increases local skin blood flow, but the mechanisms and mediators of this response (thermal hyperemia response) are incompletely elucidated. In the present study, we examined the possible dependence of the thermal hyperemia response on stimulation of muscarinic cholinergic receptors and on production of vasodilator prostanoids. In 13 male healthy subjects aged 20–30 yr, a temperature-controlled chamber was positioned on the volar face of one forearm and used to raise surface temperature from 34 to 41°C. The time course of the resulting thermal hyperemia response was recorded with a laser-Doppler imager. In one experiment, each of eight subjects received an intravenous bolus of the antimuscarinic agent glycopyrrolate (4 μg/kg) on one visit and saline on the other. The thermal hyperemia response was determined within the hour after the injections. Glycopyrrolate effectively inhibited the skin vasodilation induced by iontophoresis of acetylcholine but did not influence the thermal hyperemia response. In a second experiment, conducted in five other subjects, 1 g of the cyclooxygenase inhibitor aspirin administered orally totally abolished the vasodilation induced in the skin by anodal current but also failed to modify the thermal hyperemia response. The present study excludes the stimulation of muscarinic receptors and the production of vasodilator prostaglandins as essential and nonredundant mechanisms for the vasodilation induced by local heating in human forearm skin.

Heart rate response to atropine in humans anaesthetized with five different techniques

Atropine, 0.01 mg.kg-1, was given intravenously before the start of surgery to 169 patients who were anaesthetized with one of five different techniques; halothane, enflurane, cervical epidural, lumbar epidural or narcotic anaesthesia in addition to nitrous oxide and oxygen. Atropine produced a significant increase in heart rate (HR) within 1 min in all patients studied; the HR increases in patients anaesthetized with halothane (37 +/- 11 beats.min-1, n = 37) or narcotic (34 +/- 12 beats.min-1, n = 30) were significantly greater than in those anaesthetized with enflurane (25 +/- 10 beats.min-1, n = 35; P less than 0.01) or epidural anaesthesia. Because of the presence of an acute cardiac sympathectomy, the patients who received cervical epidural anaesthesia were expected to have different responses to the atropine. However, there was no significant difference in the HR increases between the patient groups with cervical (19 +/- 12 beats.min-1, n = 32) and lumbar (22 +/- 8 beats.min-1, n = 35) epidural anaesthesia. Atropine also produced a small but significant increase in arterial pressure in all five groups of patients. These results suggest that the cardiac responses to atropine may differ depending on the individual anaesthetic agent used, and are likely dependent upon the agent's effect on autonomic nervous system activity.

Reversal of pancuronium. Neuromuscular and cardiovascular effects of a mixture of neostigmine and glycopyrronium

Moderate to deep (67-99% single twitch depression) pancuronium-induced neuromuscular blockade was antagonised with neostigmine (30 micrograms/kg, 60 micrograms/kg, or 80 micrograms/kg) in combination with glycopyrronium. Twenty-seven patients were reversed from 91%-99% twitch depression. Recovery of the first twitch of a train-of-four to 95% of control twitch took at least 20 minutes with neostigmine 30 micrograms/kg. The higher doses were significantly faster (60 micrograms/kg p less than 0.05, 80 micrograms/kg p less than 0.01) and took 15.8 and 14.8 minutes respectively. Reversal to a train of four ratio of 0.75 was not consistently achieved in under 30 minutes with any dose of neostigmine. Nineteen patients were antagonised from a 67%-80% depression of first twitch and in all but two recovery to 95% of control took under 10 minutes. To achieve a train of four ratio of 0.75 took less than 12.5 minutes except in three patients, two of whom, both given neostigmine 30 micrograms/kg, took longer than 20 minutes. Neostigmine 60 micrograms/kg produced as rapid a degree of antagonism as 80 micrograms/kg. Heart rates after reversal decreased gradually in all groups, although the decrease was initially greater in the low dose neostigmine (30 micrograms/kg) group. A fixed 5:1 ratio of neostigmine and glycopyrronium will usually antagonise a moderate (70%-80%) pancuronium block to a train of four of greater than 75% within 12.5 minutes if at least 60 micrograms/kg of neostigmine is administered. More than 30 minutes may be required for reversal whatever the dose of neostigmine, for antagonism from greater than 90% twitch depression.

Bradycardia during intra-abdominal surgery. Modification by pre-operative anticholinergic agents

The aim of the present study was to examine, in a double-blind, randomised manner, the effects of glycopyrronium 0.005 mg/kg, atropine 0.01 mg/kg or a placebo (normal saline) on the frequency of bradycardia in 92 patients scheduled for major abdominal or gynaecological surgery. All patients received fentanyl, halothane and vecuronium. The frequency of bradycardia in the group that received saline was 18%. No cases occurred in either anticholinergic group. Mean heart rates intra-operatively were not significantly different between the atropine and glycopyrronium groups. It is suggested that the routine use of pre-operative anticholinergic agents should be considered when a similar anaesthetic technique is employed.

Comparison of atropine and glycopyrronium in patients with pre-existing cardiac disease

The effects of atropine and glycopyrronium, when given intravenously with neostigmine during the reversal of neuromuscular blockade in patients with cardiovascular disease, were compared in a double blind trial. Atropine was associated with a significantly greater elevation of heart rate and rate-pressure product than glycopyrronium. This elevation was also more sustained with atropine. The entire atropine population also showed a significantly greater incidence of ST-segment depression on the electrocardiogram than that observed in those who had received glycopyrronium. Furthermore, patients with ischaemic heart disease and previous myocardial infarction who received atropine showed a significantly greater incidence of dysrhythmias than those given glycopyrronium. It is suggested that at the time of reversal of neuromuscular blockade in patients with cardiovascular disease, glycopyrronium is a more suitable agent than atropine.

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.

Atropine vs glycopyrrolate during reversal of pancuronium block in patients anaesthetized with halothane

Atropine 0.015 mg kg-1 and glycopyrrolate 0.0075 mg kg-1 were compared as antimuscarinic agents during reversal of pancuronium block with neostigmine 0.03 mg kg-1 in 30 patients anaesthetized with thiopental-N2O-halothane and undergoing minor surgery. In patients treated with atropine-neostigmine, the frequencies of bradycardia and junctional rhythm were relatively high and about the same as those reported by us previously in patients anaesthetized with thiopental-N2O-fentanyl. As in our previous study, glycopyrrolate seemed to have advantages over atropine during reversal of pancuronium block: the incidences of bradycardia and junctional rhythm were significantly less in patients treated with glycopyrrolate. Recovery from anaesthesia, as assessed by the awakening after discontinuation of N2O and halothane administration, and the incidence of postoperative nausea and vomiting, were not significantly different between the atropine and glycopyrrolate groups.

Cardiac dysrhythmias and heart rate changes at induction of anaesthesia: a comparison of two intravenous anticholinergics

Glycopyrrolate, 0.2 mg, or atropine, 0.6 mg, was administered intravenously together with methohexitone for the induction of anaesthesia in unpremedicated patients. The use of atropine, compared with glycopyrrolate, was associated with a greater rise in heart rate, a greater number of patients whose heart rates doubled, and a higher incidence of dysrhythmias. Glycopyrrolate is recommended for use as an intravenous anticholinergic agent, particularly in patients with cardiovascular impairment.

Comparison of some postanaesthetic effects of atropine and glycopyrrolate with particular emphasis on urinary problems

Two hundred and two patients undergoing elective surgery were given either atropine (98 patients) or glycopyrrolate (104 patients) for intravenous premedication and as an adjunct to reversal of neuromuscular block by neostigmine in a double-blind study. The dose ratio of atropine and glycopyrrolate was 2.5:1. After reversal, both drugs induced an initial increase and a subsequent decrease in heart rate. The mean values in % heart rate were statistically significantly higher in the glycopyrrolate group than in the atropine group. Semiquantitative measurement of salivation showed glycopyrrolate to be more potent as an antisialogogue drug. Nausea and vomiting were equally common after both drugs. There were no differences between the drugs in the occurrence of postoperative micturition difficulties, the total rate of this complication being 18%. It is concluded that factors other than the choice of anticholinergic drug may be blamed for postoperative micturition difficulties.

Glycopyrrolate: pharmacology and clinical use

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

Dose-response studies on glycopyrrolate and atropine in conscious cardiac patients

The dose-heart rate response relationship for the two anticholinergics, atropine and glycopyrrolate, were studied in non-anaesthetised patients about to undergo coronary artery surgery. Two methods were used, the administration of increasing doses to different groups of patients, and an incremental dose technique in the same patient. Both drugs increased heart rate in a dose-related manner with glycopyrrolate being approximately twice as potent as atropine. Glycopyrrolate is as effective as atropine in correcting bradycardia prior to open heart surgery.

Atropine and glycopyrrolate: changes in cardiac rate and rhythm in conscious and anaesthetised children

Heart rate and rhythm were studied in conscious children and children under nitrous oxide and halothane anaesthesia following intravenous administration of atropine or glycopyrrolate. Both drugs produced a similar increase in heart rate when the potency of glycopyrrolate is considered twice that of atropine. There is no difference in the response of anaesthetised and awake children. Junctional rhythm is the main dysrhythmia observed which appears to occur more frequently in anaesthetised children. The administration of both drugs is safe in paediatric patients.

Advantages of glycopyrrolate over atropine during reversal of pancuronium block

Atropine 0.015 mg kg-1 and glycopyrrolate 0.0075 mg kg-1 were compared as antimuscarinic agents during reversal of pancuronium block with neostigmine 0.03 mg kg-1 in 30 patients anaesthetized with thiopental - N2O- fentanyl and undergoing minor surgery. The decrease of heart rate was more pronounced in patients who received atropine-neostigmine. The mean of the lowest heart rate was 44.3 beats min-1 in the atropine group compared with 54.3 beats min-1 in the glycopyrrolate group. Five patients with atropine-neostigmine developed a transient nodal rhythm as compared with two of those receiving glycopyrrole-neostigmine (non-significant difference). Recovery from anaesthesia, as assessed by the awakening after the discontinuation of N2O administration, was more rapid in patients given glycopyrrolate. In conclusion, glycopyrrolate seems to have advantages over atropine when used during reversal of pancuronium block with neostigmine.