Antidepressant Overdose Research Articles

Use of Sodium Bicarbonate in Cardiac Arrest: Current Guidelines and Literature Review.

The aim of the review was to summarize the literature over the last 25 years regarding bicarbonate administration in out-of-hospital cardiac arrest. A PubMed search was conducted using the terms “bicarbonates” and “cardiac arrest”, limited to human studies and reviews published in English (or at least with a meaningful abstract in English) in the last 25 years. Clinical and experimental data raised questions regarding the safety and effectiveness of sodium bicarbonate (SB) administration during cardiac arrest. Earlier advanced cardiac life support (ACLS) guidelines recommended routine bicarbonate administration as part of the ACLS algorithm, but recent guidelines no longer recommend its use. The debate in the literature is ongoing, but at the present time, SB administration is only recommended for cardiac arrest related to hypokalemia or overdose of tricyclic antidepressants. Several studies challenge the assumption that bicarbonate administration is beneficial for treatment of acidosis in cardiac arrest. At the present time, there is a trend against using bicarbonates in cardiac arrest, and this trend is supported by guidelines published by professional societies and organizations.

Tricyclic Antidepressant Intoxication; Several Complications after an Acute Poisoning by Amitriptyline and Clomipramine

Tricyclic antidepressant (TCA) toxicity is common among children and adults due to widespread use. Tricyclic ant depressive drugs are widely used in suicide attempts and present a variety of deleterious effects. In this case report we present a patient with severe poisoning by ingestion of amitriptyline and clomipramine in which many complications were observed.

Medication Overdoses at a Public Emergency Department in Santiago, Chile.

IntroductionWhile a nationwide poison control registry exists in Chile, reporting to the center is sporadic and happens at the discretion of the treating physician or by patients’ self-report. Moreover, individual hospitals do not monitor accidental or intentional poisoning in a systematic manner. The goal of this study was to identify all cases of intentional medication overdose (MO) that occurred over two years at a large public hospital in Santiago, Chile, and examine its epidemiologic profile.MethodsThis study is a retrospective, explicit chart review conducted at Hospital Sótero del Rio from July 2008 until June 2010. We included all cases of identified intentional MO. Alcohol and recreational drugs were included only when they were ingested with other medications.ResultsWe identified 1,557 cases of intentional MO and analyzed a total of 1,197 cases, corresponding to 0.51% of all emergency department (ED) presentations between July 2008 and June 2010. The median patient age was 25 years. The majority was female (67.6%). Two peaks were identified, corresponding to the spring of each year sampled. The rate of hospital admission was 22.2%. Benzodiazepines, selective serotonin reuptake inhibitors, and tricyclic antidepressants (TCA) were the causative agents most commonly found, comprising 1,044 (87.2%) of all analyzed cases. Acetaminophen was involved in 81 (6.8%) cases. More than one active substance was involved in 35% of cases. In 7.3% there was ethanol co-ingestion and in 1.0% co-ingestion of some other recreational drug (primarily cocaine). Of 1,557 cases, six (0.39%) patients died. TCA were involved in two of these deaths.ConclusionSimilar to other developed and developing nations, intentional MO accounts for a significant number of ED presentations in Chile. Chile is unique in the region, however, in that its spectrum of intentional overdoses includes an excess burden of tricyclic antidepressant and benzodiazepine overdoses, a relatively low rate of alcohol and recreational drug co-ingestion, and a relatively low rate of acetaminophen ingestion.

Ciddi Amitriptilin Zehirlenmesinde İntravenöz Lipit İnfüzyon Tedavisi Uygulaması

Ciddi Amitriptilin Zehirlenmesinde İntravenöz Lipit İnfüzyon Tedavisi Uygulaması

Toxic Ingestion/Acute Tricyclic Antidepressant (TCA) Ingestion

Abstract Introduction Acute tricyclic antidepressant (TCA) overdose is an uncommon but life threatening ingestion. The purpose of this simulation is to present an acute TCA overdose case that allow...

A Literature Review of the Use of Sodium Bicarbonate for the Treatment of QRS Widening.

Sodium bicarbonate is a well-known antidote for tricyclic antidepressant (TCA) poisoning. It has been used for over half a century to treat toxin-induced sodium channel blockade as evidenced by QRS widening on the electrocardiogram (ECG). The purpose of this review is to describe the literature regarding electrophysiological mechanisms and clinical use of this antidote after poisoning by tricyclic antidepressants and other agents. This article will also address the literature supporting an increased serum sodium concentration, alkalemia, or the combination of both as the responsible mechanism(s) for sodium bicarbonate's antidotal properties. While sodium bicarbonate has been used as a treatment for cardiac sodium channel blockade for multiple other agents including citalopram, cocaine, flecainide, diphenhydramine, propoxyphene, and lamotrigine, it has uncertain efficacy with bupropion, propranolol, and taxine-containing plants.

Survival following massive amitriptyline overdose: The use of intravenous lipid emulsion therapy and the occurrence of acute respiratory distress

While survival has been reported after ingestion of 4.25 g amitriptyline, for which intravenous lipid emulsion (ILE) therapy was administered, we recently managed a patient who made a full recovery after a 4.8 g amitriptyline overdose. Interesting features of the case were a marked response to ILE and the subsequent development of acute respiratory distress syndrome (ARDS). Our patient had taken 96 amitriptyline 50mg tablets (total 4.8 g or 80mg/kg), an uncertain amount of zopiclone, alcohol and venlafaxine. In the emergency department the patient was hypotensive and unresponsive (GCS 3), with a prolonged QTc identified on ECG. Rapid sequence induction was performed followed by transfer to the intensive care unit for full supportive therapy. Further management and key parameters are illustrated in Figure 1. Hypotension was unresponsive to fluid therapy, and noradrenaline therapy was required. Intravenous bicarbonate therapy and mild hyperventilation (with tidal volumes 6ml/kg) were utilised, aiming to achieve a pH of 7.55. Three grand mal seizures occurred which were treated with a midazolam bolus followed by an infusion. Approximately 12 h after the drug ingestion, with escalating noradrenaline requirements, ILE was administered. The subsequent improvement in blood pressure and reduction in noradrenaline can be seen in Figure 1. Case reports detailing the successful use of ILE for the treatment of toxicity of lipophilic drugs including tricyclic antidepressants are well documented. A recent prospective, randomised, controlled trial found no benefit of ILE compared to bicarbonate in a pig model of amitriptyline toxicity. A rabbit model found conflicting results. Various mechanisms have been suggested for the mechanism of action of ILE, but the lipid sink hypothesis describes how ILE may provide a large binding site for the drug, removing it from effective circulation. Given the pKa of amitriptyline of 9.4, prior alkalinisation, as was undertaken in this case, might be expected to augment the effect of ILE by decreasing the ionised portion of the drug. On day 3 of their care, our patient developed criteria of ARDS with a PaO2/FiO2 ratio of 70mmHg by day 5. Proning was required, tracheostomy was performed and a prolonged respiratory wean ensued with 40 days of invasive ventilation. There was no evidence of pulmonary aspiration at the scene of the overdose, during intubation or on the initial chest radiograph, though micro-aspiration cannot be excluded. Ultimately, Streptococcus pneumonia and mixed coliforms were grown from bronchoalveolar lavage of the patient’s lungs; however, concern was raised that ILE could have been linked to the ARDS. The patients subsequently made a full physical recovery. Acute respiratory distress syndrome has been reported in three patients in a case series of nine patients treated with ILE but, as the authors acknowledge, critically ill patients are at risk of ARDS. Furthermore, ARDS has been reported as a complication of tricyclic overdose. Nonetheless, case series into the use of lipid infusion in ARDS and septicaemia have linked it to worsening oxygenation. We believe this to be one of the highest reported overdoses of amitriptyline that has been survived and that the use of ILE contributed to this outcome. Our experience demonstrates the potential use of ILE outside the setting of cardiac arrest or cardiovascular collapse but highlights concerns regarding its potential association with ARDS.

Image diagnosis: aVR, the forgotten lead.

The 12-lead electrocardiogram has been referred to as an “11-lead study” on the basis of the false assumption that lead aVR yields only limited information. As this area is already covered by other leads (I, aVL, V5, V6), aVR was only used to confirm correct arm lead placement and was assumed to reflect only reciprocal changes from the lateral portion of the heart. As a result, the unpaired lead aVR has been largely ignored and has been coined the “forgotten lead.”1 In reality, aVR is an informative lead that also reflects the right ventricular outflow tract and the basal portion of the interventricular septum. Analysis of aVR’s individual waveforms should be performed in concert with all other leads because it can provide critical information in the management of a number of medical conditions. The ST segment in lead aVR is used in the assessment of narrow complex tachyarrhythmia. Ho et al2 reported the presence of ST elevation in aVR has a 71% sensitivity and a 70% specificity of distinguishing atrial ventricular reciprocating tachycardia (such as Wolff-Parkinson-White) from atrial ventricular nodal reentrant tachycardia. In addition, aVR morphology can also be used to distinguish wide complex supraventricular tachycardia from ventricular tachycardia. For example, in 2008 Vereckei et al3 reported a 98% sensitivity in differentiating wide complex supraventricular tachycardia from ventricular tachycardia based solely on the analysis of aVR morphology (Figure 1). Figure 1. aVR criteria from Vereckei et al1 suggestive of ventricular tacychardia: 1) presence of R wave; 2) presence of R wave or Q wave > 40 msec; 3) presence of a notch on the descending limb of the negative QRS complex; 4) voltage change in the first ... The presence of a prominent R wave in aVR is a critical finding in sodium channel blocker poisonings, such as with tricyclic antidepressants.4 Liebelt et al4 concluded that an R wave amplitude > 3.0 mm is more sensitive than QRS interval as a predictor of seizures and ventricular dysrhythmias (Figure 2). Figure 2. 12-lead electrocardiogram with a sinus rhythm characterized by a widened QRS complex, deep S wave in lead I, and prominent R wave in lead aVR. These findings are consistent with cardiotoxicity resulting from tricyclic antidepressant poisoning. Patient ... Finally, aVR is a valuable lead in the management of acute coronary ischemia. Although aVR ST-segment elevation may be an abnormal variant in supraventricular tachycardia, bundle branch blocks, left ventricular hypertrophy, or right ventricular hypertrophy, in the presence of other ischemic changes aVR ST-segment elevation is a sensitive indicator of left main, left anterior descending, or triple vessel disease.5–9 Barrabes et al6 and Kosuge et al7 have reported aVR ST-segment elevation to be an independent risk factor for increased morbidity and mortality. Therefore, the presence of aVR ST-segment elevation, in conjunction with other ischemic changes, should be considered an ST-segment elevation myocardial infarction equivalent and warrants immediate interventional reperfusion6,7,10 (Figure 3). Figure 3. 12-lead electrocardiogram from a 33-year-old man with history of hypercholesterolemia, who presented to the Emergency Department with 5 hours of anterior chest pressure associated with diaphoresis and shortness of breath. Electrocardiogram demonstrates ...

The effects of diltiazem and metoprolol in QTc prolongation due to amitriptyline intoxication.

Amitriptyline, a frequently used tricyclic antidepressant agent, has powerful cardiotoxic effects especially in high doses. Serum and urine levels of amitriptyline dosages are not correlated with severity of toxicity; therefore, it increases the importance of electrocardiography (ECG) abnormalities. The prolongation of QTc can be a predictive marker for cardiotoxicity. Hence, in this study, it is aimed to evaluate possible effects of metoprolol and diltiazem in amitriptyline toxicity. The rats were separated into four groups. First one was control group, the second was the amitriptyline + saline group, third one was the amitriptyline + metoprolol group, and forth one was the amitriptyline + diltiazem group. ECG were recorded on rats under anesthesia. In amitriptyline group, QTc duration was prolonged compared with all other groups. The prolongation of QTc was shorter in amitriptyline + metoprolol group and amitriptyline + diltiazem group than amitriptyline group (p < 0.01 and p < 0.01, respectively). According to the results, it is possible to report ameliorating effects of both metoprolol and diltiazem on QTc prolongation related with amitriptyline intoxication. With further studies, these agents may be used for amitriptyline toxicity and besides, they may be used for patients in cardiovascular risk groups who take amitriptyline treatment regularly.

Swiss Prison Suicides Between 2000 and 2010.

Background: Suicide is the leading cause of death in Swiss prisons. The Federal Statistics Office provides numbers but no further details. Previous studies worldwide have focused on identifying suicide risk factors in prisoners, but very few have looked at the methods used in relation to prevention strategies. Aims: To obtain details of Swiss prison suicides, determine new findings in an international context, and establish prevention strategies based on the information acquired. Method: Retrospective data analysis of prison suicides extracted from the database of all suicides investigated by Swiss institutes of legal medicine between 2000 and 2010, using a standardized assessment sheet. Results: Out of 4,885 suicides investigated in the institutes of legal medicine in Switzerland, we identified 50 (1.02%) inmate suicides. Most were unmarried Swiss men, with a median age of 32 years. The two most common methods used were hanging and tricyclic antidepressant overdose. Two died due to self-immolation. Conclusion: Swiss prison suicides do not differ from those in other countries regarding sociodemographic details and the most common method of hanging. Anchoring devices, even low ones, should be avoided to prevent hanging and medication intake should be monitored. As prisoners use tricyclic antidepressants to die by suicide, we recommend the general monitoring of intake.

Arterial blood gas analysis and the outcome of treatment in tricyclic antidepressants poisoned patients with benzodiazepine coingestion.

Background. Poisoning with tricyclic antidepressants (TCAs) is still a major concern for emergency physicians and intensivists. Concomitant ingestion of other psychoactive drugs especially benzodiazepines with TCAs may make this clinical situation more complex. This study aimed to compare the arterial blood gas (ABG) values and the outcome of treatment in patients with coingestion of TCA and benzodiazepine (TCA + BZD) poisoning and TCA poisoning alone. Methods. In this cross-sectional study which was carried out in a tertiary care university hospital in Iran, clinical and paraclinical characteristics of one hundred forty TCA only or TCA + BZD poisoned patients (aged 18–40 years) were evaluated. ABG analysis was done on admission in both groups. Outcomes were considered as survival with or without complication (e.g., intubation) and the frequency of TCA poisoning complications. Results. Arterial pH was significantly lower in TCA + BZD poisoning group compared with TCA only poisoning group (7.34 ± 0.08 and 7.38 ± 0.08, resp.; P = 0.02). However, other complications such as seizure, and the need for the endotracheal intubation were not significantly different. All patients in both groups survived. Conclusions. Concomitant TCA plus BZD poisoning may make the poisoned patients prone to a lower arterial pH level on hospital admission which may potentially increases the risk of cardiovascular complications in TCA poisoning.

Memory Impairment following Acute Tricyclic Antidepressants Overdose.

Background. Psychiatric consultation is necessary for all patients with intentional poisoning and its reliability depends on the proper function of patients' memory performance. This study aimed to determine the possible memory impairment following acute TCAs' poisoning. Materials and Methods. In this cross-sectional study, patients with acute TCAs poisoning were allocated to two groups of severe poisoning (with coma, seizures, cardiac arrhythmias, hypotension, and a wide QRS complex) and mild-to-moderate poisoning according to their clinical presentation at the time of hospital admission. All patients underwent memory performance test both immediately and 24 hours after their initial consciousness after admission, using Wechsler Memory Scale (WMS-IV). Results. During the study period, 67 TCA-poisoned patients (aged, 20–64 years) were evaluated, of which 67.2% were female. The mean memory scores of patients immediately and 24 hours after the initial consciousness were 31.43 ± 9.02 and 50.62 ± 9.12, respectively (P < 0.001). Twenty-four hours after the initial consciousness, memory score was statistically correlated with the amount of ingested drug and the intoxication severity. Conclusion. Following the recovery from somatic symptoms of acute TCA poisoning, patients may still suffer from memory impairment and it seems that this time is not suitable for performing a reliable psychiatric consultation.

Right bundle branch block and bradycardia in amitriptyline toxicity

Cardiovascular events are the leading cause of fatal outcome from tricyclic antidepressant (TCA) overdose; cardiotoxicity as dysrhythmias and hypotension. Electrocardiogram (ECG) abnormalities usually precede the development of significant, clinically evident cardiovascular disease, and so the ECG has manifests clinically emerged as a valuable tool in the assessment of TCA toxicity. Cardiac toxicity secondary to TCAs is due mainly to sodium-channel blockade and slowing of phase 0 depolarization of the action potential resulting in slowing of conduction through the His-Punkinje system and myocardium. Sinus tachycardia is the most common manifestation seen, other ECG changes, which are seen are premature ventricular contractions, ventricular tachycardia and fibrillation, supraventricular tachycardia with aberrancy, sinus arrest, idioventricular rhythm, pulseless electrical activity, QRS/QT/PR prolongation, rightward terminal QRS axis, increased amplitude of R aVR , atrioventricular blocks, and uncommonly as bundle branch block. Here, we discuss the ECG alterations as a right bundle branch block in a patient who was intoxicated with amitriptyline.

Self-harm in Oxford, England: epidemiological and clinical trends, 1996-2010.

Self-harm is a major healthcare problem and changes in its prevalence and characteristics can have important implications for clinical services, treatment and prevention. We analysed data on all self-harm presentations to the general hospital in Oxford between 1996 and 2010 using the Oxford Monitoring System for Self-harm. We investigated trends in prevalence, methods and repetition of self-harm, and receipt of psychosocial assessment. For patients receiving a psychosocial assessment, we investigated trends in alcohol use and misuse, prior psychiatric treatment and self-harm, problems, and suicidal intent. Rates of self-harm rose in both genders between 1996 and 2002/2003, after which they declined. There was evidence of a possible cohort effect, whereby higher rates in younger males in earlier years transferred over time to older age groups. Self-cutting, hanging and jumping became more common. Paracetamol was involved in 44.9 % of all self-poisoning episodes. Overdoses of antidepressants (particularly selective serotonin reuptake inhibitors) increased, as did those of mood stabilisers, non-opiate analgesics excluding paracetamol (e.g. non-steroidal anti-inflammatory drugs), and non-ingestible poisons. Alcohol use in relation to self-harm and alcohol-related problems became more common, as did history of prior psychiatric treatment and, especially, of self-harm, and employment problems from 2008. Despite national guidance, the proportion of patients undergoing psychosocial assessment declined. Major changes in the extent and nature of self-harm occurred over the study period, some suggestive of increased psychopathology and others reflecting prescribing practices and changes in drinking patterns. The findings emphasise the need for psychosocial assessment following self-harm, to identify treatment needs and reduce repetition.

Risk factors for QT prolongation associated with acute psychotropic drug overdose

BackgroundAntipsychotic/Antidepressant use is a risk factor for QT interval (QT) prolongation and sudden cardiac death. However, it is unclear which drugs are risk factors for QT prolongation and torsades de pointes in cases of psychotropic drug overdose. MethodsAfter correction of QT data by Bazett formula (QTc), QTc was classified into 3 categories (QTc < 440 milliseconds, 440 milliseconds ≤ QTc < 500 milliseconds, and QTc ≥ 500 milliseconds), and the blood concentration of each drug was classified as not detected, therapeutic range, or toxic range. The association of the blood concentration of each drug with QTc was analyzed using the ordinal logistic regression model. Drugs that induced QT–heart rate pairs higher than the at-risk line of Isbister's QT–heart rate nomogram (QT nomogram) were further analyzed using the binomial logistic regression model. ResultsA total of 649 patients were enrolled in the study. The independent risk factors for QTc prolongation were therapeutic and toxic range of phenotiazine antipsychotic drug (therapeutic range: odds ratio [OR], 1.56 [P = .039]; toxic range: OR, 3.85 [P < .001]), and toxic range of cyclic antidepressants (OR, 2.39; P = .018). In addition, toxic range of phenotiazine antipsychotic drug (OR, 3.87; P = .012) and tricyclic antidepressants (OR, 4.94; P < .001) were risk factors for QT higher than the at-risk line of the QT nomogram. ConclusionsThe possibility of QT prolongation and torsades de pointes due to overdose of phenotiazine antipsychotic drug or tricyclic antidepressants requires particular consideration.

Extracorporeal Treatment for Tricyclic Antidepressant Poisoning: Recommendations from the EXTRIP Workgroup

The Extracorporeal Treatments In Poisoning (EXTRIP) workgroup was formed to provide recommendations on the use of extracorporeal treatments (ECTR) in poisoning. Here, the workgroup presents its results for tricyclic antidepressants (TCAs). After an extensive literature search, using a predefined methodology, the subgroup responsible for this poison reviewed the articles, extracted the data, summarized findings, and proposed structured voting statements following a predetermined format. A two-round modified Delphi method was chosen to reach a consensus on voting statements and RAND/UCLA Appropriateness Method to quantify disagreement. Blinded votes were compiled, returned, and discussed in person at a meeting. A second vote determined the final recommendations. Seventy-seven articles met inclusion criteria. Only case reports, case series, and one poor-quality observational study were identified yielding a very low quality of evidence for all recommendations. Data on 108 patients, including 12 fatalities, were abstracted. The workgroup concluded that TCAs are not dialyzable and made the following recommendation: ECTR is not recommended in severe TCA poisoning (1D). The workgroup considers that poisoned patients with TCAs are not likely to have a clinical benefit from extracorporeal removal and recommends it NOT to be used in TCA poisoning.

Varicella zoster virus (VZV) in cerebral arteries of subjects at high risk for VZV reactivation

With a decline in varicella zoster virus (VZV)-specific cell-mediated immunity, VZV can reactivate, infect cerebral arteries and cause stroke. Previous studies of cerebral arteries from subjects without a history of transient ischemic attacks or stroke revealed no VZV DNA or VZV antigen; however, VZV DNA and VZV antigen were found in the cerebral arteries of a subject with diabetes, a known risk factor for VZV reactivation and zoster. The present study analyzed an additional 55 cerebral arteries from 18 subjects with co-morbidities that may increase risk of VZV reactivation: a history of alcohol abuse, tricyclic antidepressant intoxication, cocaine abuse, HIV or being over age 70years. VZV antigen was detected in 24 (44%) cerebral arteries from 14 (78%) subjects.

Amitriptyline, clomipramine, and doxepin adsorption onto sodium polystyrene sulfonate

Purpose of the studyComparative in vitro studies were carried out to determine the adsorption characteristics of 3 drugs on activated charcoal (AC) and sodium polystyrene sulfonate (SPS). Activated charcoal (AC) has been long used as gastric decontamination agent for tricyclic antidepressants (TCA).MethodsSolutions containing drugs (amitriptyline, clomipramine, or doxepin) and variable amount of AC or SPS were incubated for 30 minutes.ResultsAt pH 1.2 the adsorbent: drug mass ratio varied from 2 : 1 to 40 : 1 for AC, and from 0.4 : 1 to 8 : 1 for SPS. UV–VIS spectrophotometer was used for the determination of free drug concentrations. The qmax of amitriptyline was 0.055 mg/mg AC and 0.574 mg/mg SPS, qmax of clomipramine was 0.053 mg/mg AC and 0.572 mg/mg SPS, and qmax of doxepin was 0.045 mg/mg AC and 0.556 mg/mg SPS. The results of adsorption experiments with SPS revealed higher values for the qmax parameters in comparison with AC.ConclusionIn vitro gastric decontamination experiments for antidepressant amitriptyline, clomipramine, and doxepin showed that SPS has higher qmax values than the corresponding experiments with AC. Therefore, we suggest SPS is a better gastric decontaminating agent for the management of acute TCA intoxication.

Serotonin toxicity from antidepressant overdose and its association with the T102C polymorphism of the 5-HT2A receptor

Serotonin toxicity results from serotonin excess in the central nervous system from serotonergic drugs. Previous studies suggest an association between T102C polymorphism of the serotonin 2A (5-hydroxytryptamine 2A) receptor gene and serotonergic adverse effects with serotonergic drugs. We aimed to determine whether there is an association between the T102C polymorphism and serotonin toxicity in patients taking serotonergic drug overdoses. Ninety-five patients presenting with serotonergic drug overdoses were examined for serotonin toxicity and had blood collected for DNA analysis. A diagnosis of serotonin toxicity was made in 14 patients (15%) based on the Hunter Serotonin Toxicology Criteria. Four of the 14 patients (29%) with serotonin toxicity had the C/C genotype compared with 20/81 (25%) without serotonin toxicity. There were no differences in age or sex, but the median defined daily dose taken by patients with serotonin toxicity was 27 (14-84) compared with 18 (2-136) in patients without serotonin toxicity (P=0.06). There was no association between serotonin toxicity and the T102C polymorphism in patients taking a serotonergic drug overdose.

Clinical study of poisoned cases by some drugs admitted to the menoufia poisoning control center over 1 year (2011), with a focus on ECG changes

ObjectiveThe aim of this work was to study ECG changes in cases of poisoning by digoxin, theophylline, and antidepressant overdose that were admitted to Menoufia Poisoning Control Center (MPCC) in 2011, with a focus on evaluation of ECG changes in correlation with both arterial blood gases and electrolyte changes, together with clinical manifestations.BackgroundNumerous drugs can cause ECG changes and lead to cardiac dysrhythmias, and the diagnoses and subsequent management of patients with ECG changes following poisonings can be a challenge for even the most experienced physician. Digoxin toxicity often presents with gastrointestinal side effects, cardiac dysrhythmias, and neurological effects. Overdoses of antidepressants are common and deadly, and sudden cardiovascular deterioration is the hallmark of toxicity. Theophylline overdose can lead to neurotoxicity and cardiac toxicity associated with life-threatening dysrhythmias.Patients and methodsIn this study, patients who had overdosed on digitalis, theophylline, and antidepressants admitted to MPCC in 2011 were included. Clinical data, serum electrolytes, arterial blood gas changes, and ECG changes were assessed.ResultsA total of 77 patients were studied. Most patients in the study were females in the age group of 20 to less than 40 years, and they outnumbered males in both suicidal and accidental modes. Theophylline overdose cases were the most common, followed by antidepressants and then digoxin overdose. A significant relation was found between the type of drug overdose and clinical manifestations, wherein vomiting occurred most frequently with digoxin overdose. Convulsions occurred only in cases of overdose with antidepressants. Hypokalemia was more evident in cases of overdose with antidepressants. In terms of ECG changes, sinus bradycardia and ST segment depression were found only in digoxin overdose cases. Sinus tachycardia occurred most frequently in theophylline overdose cases. A highly significant relation was found between potassium (K + ) blood-level and ECG changes such as sinus tachycardia and ST segment depression. A significant relation was found between metabolic acidosis and a wide QRS complex. No case fatality was recorded in this study.ConclusionDrug overdose is a major and longstanding source of morbidity worldwide. Digitalis overdose manifested as sinus bradycardia and ST segment depression. Theophylline overdose manifested as sinus tachycardia and antidepressant overdose cases were characterized by sinus tachycardia and a wide QRS complex.