Intravenous Atropine Research Articles

A case of anaphylactic reaction to oxytocin in a parturient undergoing emergency caesarean section

Anaphylaxis to oxytocin is a rare but critical complication that can arise during labor and delivery [1], necessitating rapid recognition and management. We describe the case of a 20-year-old term primigravida with gestational hypertension who underwent an emergency lower segment caesarean section (LSCS) due to fetal distress. After successful spinal anesthesia with 0.5% bupivacaine, an infusion of 10 U oxytocin was initiated immediately following the delivery of the infant. Shortly thereafter, the patient developed acute respiratory distress, hypotension, and swelling of the lips and tongue, which progressed to bradycardia and a drop in oxygen saturation. Emergency intubation was performed due to significant airway edema, and resuscitation included intravenous adrenaline, atropine, hydrocortisone, pheniramine, and deriphylline. The surgical procedure concluded uneventfully, and the patient was transferred to the ICU for mechanical ventilation. She was extubated the following day and discharged five days later without complications. This case underscores the rare occurrence of anaphylaxis due to oxytocin administration. It highlights the need for vigilance and preparedness for allergic reactions in obstetric settings, as well as the importance of having alternative uterotonics available.

Comprehensive Clinical Assessment of Patients With Acute Organophosphorus Poisoning in a Tertiary Care Hospital.

Background The use of organophosphorus (OP) compounds as pesticides is widespread, particularly in developing nations such as India. These substances are easily accessible and often linked to suicide poisoning incidents, especially among distressed farmers. In India, OP poisoning remains a significant cause of emergency hospital admissions. This study aims to analyze the clinical profile of patients admitted with OP poisoning, focusing on the various clinically significant characteristics and aspects associated with these cases. Methods Throughout the course of two years (from June 2022 to May 2024), five hospitals with critical care units participated in this prospective observational study. These hospitals referred patients to the Prathima Institute of Medical Sciences, which served as the central facility for the study. The study focused on individuals who arrived at the emergency room within 24 hours of acute exposure to organophosphate pesticides. A total of 150 patients meeting the inclusion criteria were enrolled. Data collection included a comprehensive clinical examination, detailed patient history, and monitoring of the response to intravenous atropine. The severity of the poisoning was evaluated using the Peradeniya Organophosphorus Poisoning (POP) scale, adapted for this study. Statistical analysis was performed using IBM SPSS Statistics for Windows, Version 23 (Released 2015; IBM Corp., Armonk, New York), with descriptive statistics used to summarize the categorical and continuous variables. Results The results of the study demonstrated a notable relationship between the arrival time at the health facility and mortality rates among patients with OPpoisoning. Patients who arrived within three hours had a mortality rate of 13.2% (five out of 38 cases), while those arriving between three and six hours had a slightly higher rate of 14.3% (10 out of 70 cases). The mortality rate sharply increased to 28.6% (12 out of 42 cases) for patients who arrived after six hours. Among the OP compounds, monocrotophos showed the highest mortality rate at 80% (eight out of 10 cases), followed by dimethoate with 42.9% (12 out of 28 cases) and dichlorvos with 62.5% (five out of eight cases). The overall mortality rate in the study was 22.7% (34 out of 150 cases). Conclusions Poisoning with OP has primarily impacted young, productive men. Considerable mortality results from a disease condition that is more severe at presentation. It is advised to selectively outlaw the riskier substances that account for a larger percentage of fatalities.

Mad honey (wild honey) poisoning: clinical case series from Nepal.

Mad honey is commonly used for hypertension, and coronary artery disease, and as a sexual stimulant. Patients with mad honey poisoning present with dizziness, nausea, syncope, blurred vision, bradycardia, and hypotension with ECG findings of sinus bradycardia, complete AV block, and ST elevation. Here, the authors report five cases admitted to our tertiary care center following the consumption of mad honey. The amount of ingestion of honey varies from 1 to 2 teaspoons (~10-20ml). Most of the cases presented with chief complaints of nausea, dizziness, and vomiting, and all the cases had hypotension and bradycardia. Two cases were admitted to the ward and three of them were admitted to the ICU for further management. They were managed with intravenous fluid, injection atropine along with adjunctive vasopressor and oxygen whenever necessary. Mad honey contains grayanotoxin extracted from the nectar of Rhododendron species. This honey contains grayanotoxin, which binds to sodium channels in its open state causing hyperpolarization of the sodium channel predominantly causing gastrointestinal, neurological, and respiratory symptoms. Intravenous fluids and injection atropine are the mainstays of management in an ICU setup. Some also may require vasopressors. Mad honey poisoning is rare, and limited cases have been reported in Nepal. Physicians should consider mad honey poisoning in cases with ingestion history and clinical symptoms, as it may be a clinical diagnosis due to limited lab tests for grayanotoxin intoxication. Supportive management still forms the cornerstone for its management after diagnosis.

Bradycardic peri-arrest after electrical cardioversion for atrial fibrillation: a case report

Electrical cardioversion can precipitate prolonged bradycardia and cardiac arrest when the sinoatrial node is dysfunctional, and the escape rhythms from the atrioventricular node and ventricles fail to take over. We report the case of an elderly male who rapidly progressed into bradycardic peri-arrest after electrical cardioversion for persistent atrial fibrillation. Despite the immediate initiation of intravenous atropine and transcutaneous pacing, 2 minutes of cardiopulmonary resuscitation with further boluses of atropine and adrenaline were required before the return of spontaneous circulation. The patient was transferred to the intensive care unit, and a permanent pacemaker was implanted before discharge. Advanced age, long duration of atrial fibrillation, previous aortic valve replacement, use of anti-arrhythmic drugs, and intravenous propofol bolus were all contributing factors to this event. We summarise the relevant clinical features, risk factors, and management considerations, in the hope of promoting awareness of this rare complication of a common procedure.

Atropine sulfate may be effective to recover the unstable hemodynamics in coronary artery spasms related to atrial fibrillation ablation procedures.

Coronary artery spasms related to atrial fibrillation ablation procedures could cause lethal ventricular fibrillation or cardiopulmonary arrest. It may be useful to try intravenous atropine sulfate while preparing urgent coronary artery angiography in hemodynamically unstable coronary artery spasms cases to prevent development of the lethal arrhythmias.

Zuclopenthixol decanoate toxicity in an 8‐month‐old colt causing extrapyramidal neurological signs

SummaryZuclopenthixol decanoate is a dopamine antagonist licensed for human use to manage schizophrenia and paranoid psychosis. It is in the same drug class (thioxanthene) as fluphenazine decanoate, a drug whose use in horses is reported anecdotally for providing long‐acting sedation. This case study describes severe extrapyramidal signs seen in a Thoroughbred colt after zuclopenthixol decanoate administration. The colt was presented to a referral hospital for an unusual manifestation of colic signs. On admission, the colt began to show clear extrapyramidal neurological signs. The initial suspicion was of fluphenazine decanoate toxicity, which in the limited published literature is treated with intravenous formulations of diphenhydramine hydrochloride and benztropine mesylate. At the time of writing both were unavailable in the United Kingdom without an import license. The closest alternative option, oral diphenhydramine was administered alongside intravenous atropine and pergolide. Improvements in the colt's demeanour and neurological status was noted within 24 h. The colt was hospitalised for a total of 26 days and at time of discharge was clinically normal. Follow‐up communication 3 months after discharge confirmed that the colt had remained neurologically normal. Crucially, toxicology testing submitted to Cornell University was negative for common toxins, including fluphenazine decanoate. Specific secondary testing was performed after suspicion the administration of zuclopenthixol decanoate was raised, which was positive for this compound. Routine drug testing would, therefore, not identify the use of this behaviour modifying drug. Clinical data regarding the use of zuclopenthixol in animals is limited to its use in the translocation of wildlife to relieve stress and aid acclimatisation. To our knowledge, there is no available literature describing the administration of zuclopenthixol decanoate in equine patients.

Vago-splenic signal transduction of cardioprotection in humans.

The spleen serves as an important relay organ that releases cardioprotective factor(s) upon vagal activation during remote ischaemic conditioning (RIC) in rats and pigs. The translation of these findings to humans was attempted. Remote ischaemic conditioning or electrical auricular tragus stimulation (ATS) were performed in 10 healthy young volunteers, 10 volunteers with splenectomy, and 20 matched controls. Venous blood samples were taken before and after RIC/ATS or placebo, and a plasma dialysate was infused into isolated perfused rat hearts subjected to global ischaemia/reperfusion. Neither left nor right RIC or ATS altered heart rate and heart rate variability in the study cohorts. With the plasma dialysate prepared before RIC or ATS, respectively, infarct size (% ventricular mass) in the recipient rat heart was 36 ± 6% (left RIC), 34 ± 3% (right RIC) or 31 ± 5% (left ATS), 35 ± 5% (right ATS), and decreased with the plasma dialysate from healthy volunteers after RIC or ATS to 20 ± 4% (left RIC), 23 ± 6% (right RIC) or to 19 ± 4% (left ATS), 26 ± 9% (right ATS); infarct size was still reduced with plasma dialysate 4 days after ATS and 9 days after RIC. In a subgroup of six healthy volunteers, such infarct size reduction was abrogated by intravenous atropine. Infarct size reduction by RIC or ATS was also abrogated in 10 volunteers with splenectomy, but not in their 20 matched controls. In humans, vagal innervation and the spleen as a relay organ are decisive for the cardioprotective signal transduction of RIC and ATS.

Cardiovascular effects of poisoning following ingestion of dried Rhododendron flower in a middle-aged woman: a case report

Rhododendron toxicity can be life-threatening or fatal when manifested with cardiovascular and neurological adverse effects. A 56-year-old woman presented with dizziness, chest tightness, shortness of breath, and a tingling sensation in her face and limbs after ingestion of dried flowers of Rhododendron. On examination, she had sinus bradycardia and hypotension. She was admitted for monitoring and observation. She was managed with intravenous crystalloids, noradrenaline infusion, and atropine. Her vital parameters were normalised and was discharged after 24 hours. These symptoms were most likely due to grayanotoxin found in the Rhododendron species. This case highlights the need to raise awareness on the risks of plant poisoning due to rhododendrons and to seek timely medical care in case of symptoms. Clinicians are recommended to take context-specific history to identify potential aetiologies of poisoning.

Intensive care management of organophosphate insecticide (sniper) poisoning: a Preventable death—a case series

Background Organophosphate poisoning is the commonest accidental and suicidal poisoning in developing countries like Nigeria. Respiratory distress, unconsciousness, and acute cholinergic crisis are reasons for critical care. Objective We determined the clinical presentation and outcome following sniper poisoning in critically ill patients. Methods This was a retrospective case series of 13 patients managed for sniper poisoning in a six-bed private intensive care unit in Lagos, Nigeria, from June 2016 to June 2022. The diagnosis of sniper poisoning was made based on a positive history of ingestion of sniper before presentation, and clinical signs of cholinergic hyperactivity. Results A total of 13 patients were reviewed, 3 females and 10 males with median age and APACHE II score of 23.5 years (IQR, 5.75, 27.75) and 26 (IQR, 24, 27.5), respectively. Deliberate ingestion of sniper occurred in 10 patients. Respiratory insufficiency/unconsciousness, and bradycardia/hypoxia occurred in 11 and 10 patients, respectively. The median duration of ICU admission was 6.5 days, (IQR: 4, 8). Intravenous atropine and glycopyrrolate were administered in 10 and 2 patients, respectively. The median dose of atropine on days 1, 2, and 3 were 38.9 mg, 27.6 mg and 18.5 mg, respectively. Mechanical ventilation was initiated in 10 patients, 8 of whom were discharged home. Out of 13 patients, 10 survived, while 3 died. Conclusion This case series showed that sniper poisoning is a life-threatening condition that requires immediate diagnosis and treatment. Early referral for critical care, initiation of atropine, and supportive mechanical ventilation can save lives.

Comparing Effectiveness and Safety of Intravenous Atropine with Topical Tetracaine in Preventing and Relieving Oculocardiac Reflex in Patients Undergoing Strabismus Surgery: A Randomized Clinical Trial

Abstract Background: Oculocardiac reflex (OCR) is one of the serious complications following surgical therapeutic procedures for strabismus. Various medications have been tested to prevent or mitigate this complication. We aimed to compare the effect of intravenous atropine and topical tetracaine on the incidence and severity of OCR in strabismus surgery. Materials and Methods: In this triple-blind randomized clinical trial study, 120 patients who were candidates for strabismus surgery were randomly assigned to receive intravenous atropine, topical tetracaine, or artificial tears as the control. The incidence of OCR and its severity along with the changes in hemodynamic conditions were compared across the groups. Results: The incidence rate of OCR in the groups receiving atropine, tetracaine, and the control was found to be 17.5%, 25.0%, and 32.5% in the releasing phase without any difference, respectively (P = 0.303); however, it was 2.5%, 7.5%, and 25.0%, respectively, in the cutting phase, indicating a lower rate in the group receiving tetracaine (P = 0.004). Similarly, there was no difference in the severity of OCR across the three study groups in the releasing phase (P = 0.666); however, in the cutting phase, OCR was revealed to be milder in the group receiving atropine as compared to other groups (P = 0.033). Prescribing atropine led to higher mean systolic blood pressure and mean arterial pressure during surgery. Conclusion: The injection of atropine can effectively reduce the incidence of OCR during strabismus surgery and reduce its severity if this reflex occurs.

Nasocardiac Reflex: A Unique Clinical Phenomenon during Augmentation Rhinoplasty – Role of Sphenopalatine Ganglion Block

Abstract Nasocardiac reflex is a trigeminovagal reflex that occurs during procedures in and around the nasal mucosa. It is characterized by a chain of events similar to vasovagal syncope. A case of nasocardiac reflex developed intraoperatively during augmentation rhinoplasty in a young female being operated on for saddle nose deformity. The occurrence of transient vagal response during surgical dissection of the nasal septum was evident in the form of severe bradycardia and hemodynamic instability. To complete the surgery without undue consequences, the situation was managed with transient stoppage of surgery, followed by intravenous atropine and topical infiltration of the involved nasal mucosa with 10 ml of 2% lignocaine.

Acute white-out lung in mechanically ventilated patient

ABSTRACT A 64-year-old male with a history of chronic kidney disease-5, type 2 diabetes mellitus (T2DM), and hypertension presented with syncope and weakness. Initial examination revealed a heart rate (HR) of 18/min and blood pressure (BP) of 140/90 mmHg. Intravenous (iv) atropine was administered, increasing HR to 85/min. Subsequently, the patient became pulseless, unconscious, and unresponsive, necessitating cardiopulmonary resuscitation (CPR) as per Advanced Cardiovascular Life Support (ACLS) protocol. Return of spontaneous circulation (ROSC) was achieved after three CPR cycles, and the patient regained consciousness. He was intubated and transferred to the intensive care unit. The patient, a smoker with a 4.5 pack-year history, experienced increased positive end-expiratory pressure (PEEP), elevated plateau pressure, and inadequate tidal volume generation a day later. Auscultation revealed significantly reduced air entry on the right side. Arterial blood gas (ABG) analysis indicated CO2 retention. Chest X-ray showed a white-out right lung, intercostal narrowing, and mediastinal shift toward the ipsilateral side.

A Systemic Review of Organophosphorus Poisoning by Analyzing the Case Report

Introduction: Poison is any substance that obstructs with ordinary body functions and is capable of affecting adverse effects in living organisms. Self-poisoning from organophosphorus [OP] pesticides is a significant clinical issue in rural areas of developing countries and is responsible for an estimated 2,00,000 fatalities annually. Suspicion recognizable clinical symptoms the odour of pesticides or solvents and decreased butyrylcholinesterase activity in the blood are used for diagnosis. Case Study: A 30 years old female patient was admitted in a Tertiary Care Hospital, with an alleged history of dimethoate compound poisoning. On arrival the patient was drowsy responds to painful stimuli and afebrile. The treatment was begin with Gastric lavage with normal saline Inj.Pralidoxime in an intravenous route and Atropine was also administered intravenously and repeated every 5 minutes until the pupil dilated and Ranitidine was given to prevent ulceration. Discussion: The initial method to treat organophosphorus poisoning is to decontaminate the patient by removing and destroying all clothing and using drying agent such as flour sand or bentonite. The patient's irrational usage of medication therapy causes a worsening of the condition and a 10- to 15-day hospitalization. Conclusion: As per the standard treatment guidelines, atropine should be given as first-line therapy because muscarinic effects are reversed by atropine. By providing this to the patient, you will minimise the severity of their illness minimise down on their stay in the hospital and ultimately save their lives.

Study of Organophosphorus Poisoning at a Tertiary Care Teaching Hospital

Introduction: Organophosphate (OP) insecticides inhibit both cholinesterase and pseudo-cholinesterase activities. The inhibition of acetylcholinesterase causes accumulation of acetylcholine at synapses, and overstimulation of neurotransmission occurs as a result of this accumulation. The mortality rate of OP poisoning is high. Early diagnosis and appropriate treatment is often life saving. Treatment of OP poisoning consists of intravenous atropine and oximes. The clinical course of OP poisoning may be quite severe and may need intensive care management. Methods: A retrospective study was performed on the patients with OP poisoning. Fifty patients were included. Diagnosis was performed from the history taken either from the patient or from the patient's relatives about the agent involved in the exposure. Diagnosis could was confirmed with serum and red blood cell anticholinesterase levels. Intravenous atropine and pralidoxime was administered as soon as possible. Other measures for the treatment were gastric lavage and administration of activated charcoal via nasogastric tube, and cleansing the patient's body with soap and water. The patients were intubated and mechanically ventilated if the patients had respiratory failure, a depressed level of consciousness, which causes an inability to protect the airway, and hemodynamic instability. Mechanical ventilation was performed as synchronized intermittent mandatory ventilation + pressure support mode, either as volume or pressure control. Positive end expiratory pressure was titrated to keep SaO2 above 94% with 40% FIO2. Weaning was performed using either T-tube trials or pressure support weaning. The chi-square test was used for statistical analysis. Data are presented as mean ± standard deviation. Results: There were 26 female and 24 male patients. Thirty-five were suicide attempts and 15 were accidental exposure. The gastrointestinal route was the main route in 44 patients. The most frequent signs were meiosis, change in mental status, hypersalivation and fasciculations. Ten patients (20.0%) required mechanical ventilation. Complications were observed in 35 patients. These complications were respiratory failure (14 patients), aspiration pneumonia (10 patients), urinary system infection (6 patients), convulsion (4 patients) and septic shock (1 patient). The duration of the intensive care stay was 5.2 ± 3.0 days. Discussion: Ingestion of OP compounds for suicidal purposes is a major problem, especially in developing countries. Thirty-five of our patients used the OP insecticide for suicide. The average respiratory rate of these patients increased from 22 to 38 breaths/min, which is an important sign of respiratory distress. The nurse to patient ratio was increased after these events. Early recognition of respiratory failure resulting in intubation and mechanical ventilation is a life-saving intervention for patients with OP poisoning. Respiratory failure is the most troublesome complication, which was observed in 35 patients. Patients with OP poisoning may have respiratory failure for many reasons, including aspiration of the gastric content, excessive secretions, pneumonia and septicemia complicating acute respiratory distress syndrome. Conclusions: OP insecticide poisoning is a serious condition that needs rapid diagnosis and treatment. Since respiratory failure is the major reason for mortality, careful monitoring, appropriate management and early recognition of this complication may decrease the mortality rate among these patients.

Reação de hipersensibilidade após administração intravenosa de meloxicam em cães - relato de casos

ABSTRACT Although rarely reported in veterinary medicine, this article shows three cases of dogs that presented anaphylactic reactions after intravenous administration of meloxicam at therapeutic doses. Three dogs of different breeds and ages were submitted to anesthesia for surgical procedures of ovariohysterectomy and repair of patellar luxation. The animals were classified as ASA I and did not present changes in clinical and laboratory tests. All dogs were anesthetized and monitored by anesthesiologists, with careful multiparametric evaluation. Near the end of the procedures, meloxicam was administered intravenously in all dogs, and the drug used had the same commercial presentation and concentration, but with different lot numbers and with different months. For less than a minute, the animals showed significant hypotension, with pressure values close to 30 mmHg or inaudible by Doppler. The animals had no skin signs, only hypotension and a decrease in heart rate in one of them. All dogs were immediately treated with intravenous ephedrine and atropine in the bradycardic patient. After the emergency treatment, the dogs showed stabilized vital signs, with no complications or need for additional intervention. After the event, the three dogs showed no signs of clinical, behavioral or laboratory changes.

Mad honey poisoning presenting with syncopal attack: a case report.

The authors report a case of 62 years old male with mad honey poisoning who was presented to the emergency department with loss of consciousness and had bradycardia and hypotension on arrival. The patient received intravenous fluids, atropine, and vasopressor support and was closely monitored in the coronary care unit for 48h. Grayanotoxin I and II are believed to be primarily responsible for mad honey intoxication and act by persistent activation of voltage-gated sodium channels. Hypotension, dizziness, nausea, vomiting, and impaired consciousness are the common presentation of mad honey intoxication. Toxic effects are usually mild and close monitoring for 24-48h is sufficient but life-threatening complications like cardiac asystole, convulsions, and myocardial infarction have also been reported. Most cases of mad honey intoxication only need symptomatic treatment and close observation but the potential for deterioration and life-threatening complications must also be considered.

Management of mad honey intoxication with suspected anaphylaxis in Nepal: a case report.

The authors reported the case of a middle-aged male patient who presented with blurring of vision, passage of loose stools, vomiting, and profuse sweating after ingestion of honey. He also had a history of loss of consciousness. On presentation, he was hypotensive and tachypneic with cold, clammy extremities. His ECG showed sinus bradycardia. The authors made a diagnosis of mad honey intoxication with suspected anaphylaxis. The authors treated him with intravenous normal saline, epinephrine, and atropine. He again developed hypotension and bradycardia in a few hours, for which hydrocortisone was administered, following which his heart rate was normalized in 2h. Overall, the recovery time in our patient was 8h. The patient was counseled to avoid consuming mad honey and did well on his monthly follow-up. Our patient had signs and symptoms suggesting intoxication following ingestion of mad honey with suspicion of anaphylaxis. Similar to other reported cases, the patient had sinus bradycardia and hypotension. Epinephrine and atropine were administered to treat hypotension and bradycardia, respectively. Also, refractory hypotension was managed by intravenous hydrocortisone. Usually, atropine and saline infusion are sufficient to manage these cases, and simultaneous use of epinephrine and atropine should be avoided unless indicated. Our case highlighted the approach to diagnosing and treating mad honey intoxication with suspected anaphylaxis.

Comparison Between Prophylactic use of Atropine and Glycopyrolate in Prevention of Spinal Induced Hypotension in Patients Undergoing C-Section

Objective: The purpose of this study is to compare the efficacy of atropine and glycopyrrolate in reducing the risk of hypotension caused by spinal anesthesia in patients undergoing caesarean sections. Methods: After ethical approval from institution review board, this randomized control was carried out at Liaqat national hospital and medical college. 332 pregnant women in a row who had chosen to have a caesarean section were enlisted through non-probability consecutive sampling technique. Subjects were randomly assigned to one of two groups of 166 using computer-generated randomization tables. Group A Patients received intravenous atropine in dose of 0.01mg/kg before inducing spinal anesthesia. Group B Patients received intravenous glycopyrrolate in dose of 0.01mg/kg before inducing spinal anesthesia. Pre-surgical, operational, and post-operative treatment for all patients was adhered to the same established protocols. Results: The mean age of the participants in both study groups were 26.28±4.03 and 26.07±3.78 years. The mean weight of the participants in both study groups were 75.24±7.6 and 74.17±7.54 Kg. The mean gestation age of the participants in both study groups were 38.82±1.17 and 38.70±1.19 months. The heart rate (HR) 15-minutes after the administration of atropine in group A was 94.89±11.8, and in Group B after administration of glycopyrrolate was 98.18±11.5. A significant difference (P=0.045) in the mean HR of the participants in both study groups was observed. The Mean Arterial Pressure (MAP) 15-minutes after the administration of atropine in group A was 76.63±7.9, and in Group B after administration of glycopyrrolate was 79.6±10.5. A significant difference (P=0. 0.029) in the mean MAP of the participants in both study groups was observed. Conclusion: Glycopylorate, atropine, spinal anesthesia, hypotension, heart rate

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

Transient asystole associated with vasovagal reflex in an oral surgery patient: A case report

The perioperative cardiac events may be brought about by a relative imbalance of autonomic activities due to excessive psychological and physical stress. The present case study focuses on the asystole that can occur as a serious cardiac adverse event associated with vasovagal reflex likely to be triggered by venipuncture for securing an intravenous line during dental care. In addition, we describe and discuss herein the management of intravenous sedation for a dental phobic patient who experienced the vasovagal reflex involved in an unexpected transient asystole. The patient with vasovagal reflex episodes in daily life, who had no past medical history relevant to cardiovascular disorders, was scheduled for dental extraction under intravenous sedation. Immediately after peripheral intravenous catheterization, she complained of discomfort and nausea, and a II-lead electrocardiogram revealed asystole following bradycardia associated with vasovagal reflex. Oxygenation and intravenous fluid loading in the supine position with elevation of the lower extremities restored sinus rhythm and normal hemodynamics without the intervention of cardiopulmonary resuscitation. With administration of intravenous atropine and betamethasone as premedication, she was uneventfully treated in stress-free psychosomatic conditions under optimal sedation with midazolam without any signs of cardiovascular disorders. After administration of flumazenil, the patient satisfactorily recovered from sedation without re-sedation. The present case suggests that an asystole associated with vasovagal reflex can be triggered by venipuncture for intravenous catheterization during dental anxiety likely to affect the imbalance between sympathetic and parasympathetic activities.