A case of altruistic suicide by severe carbon monoxide poisoning

Abstract

Carbon monoxide poisoning (CO) is a lethal form of suicide. We present a case of a 52-year-old otherwise healthy male who attempted suicide by CO poisoning due to altruistic intentions. The patient survived and was doing well on follow-up over 2 months after discharge. The aims of this case report are to discuss the psychiatric and medical sequelae of CO poisoning and to revisit the sociological concept of suicide, focusing on altruistic suicides.

Introduction

In 2019, the World Health Organization reported more than 700,000 people died by suicide. ¹ According to the American Journal of Preventive Medicine, inhalation of gases accounted for 5%–15% of suicides internationally. ² The National Violent Death Reporting System documented that most suicides committed via inhalation of gases were due to carbon monoxide (CO) poisoning. ³ While inhalation of CO via motor vehicles is declining due to the addition of catalytic converters, charcoal-related CO poisoning has increased dramatically, especially in Asia.^{4, 5} CO is often indicated as the “silent killer” because of its tasteless and odorless nature which turns lethal very quickly. ⁶ Once a patient is impacted by CO, nervous system deterioration leads to neuropsychiatric manifestations, often resulting in changes in mental status and behaviors. ⁷

We present a case where the patient displayed bilateral globus pallidus infarcts as a result of CO toxicity in a suicide attempt.

Case

A 52-year-old male was brought to the hospital for an intentional suicide attempt. He was found by his wife in the garage with a generator running and a car engine on. It is not clear how long he was in the garage. He had left a suicide note. He had agonal respirations and was intubated for airway protection by EMS before being brought to the hospital. He was initially admitted to the intensive care unit. Initial lab work revealed arterial blood co-oximetry gas analysis with a pH of 7.2 (normal range 7.350–7.450), partial pressure of oxygen (pO2) 190.4 mm Hg, pCO2 42.6 mm Hg, and carboxyhemoglobin level of 20.7% (normal ⩽3%). Complete blood count (CBC) revealed an elevated white blood cell count of 18.47 × 1000 per µL (4.80–10.80 × 1000/µL), predominantly neutrophils (84%). Complete metabolic panel (CMP) was significant for acute kidney injury with creatinine of 2.26 mg/dL ( 0.60–1.20 mg/dL), and transaminitis with AST 54 U/L (5–40 U/L) and ALT 85 (10–45 U/L). Blood alcohol levels were 59 mg/dL and urine toxicology screen was negative. Brain MRI without contrast revealed the presence of an acute infarct of the left globus pallidus and an acute punctate infarct of the right globus pallidus, consistent with CO poisoning/hypoxic-ischemic injury (see Figure 1). Serial carboxyhemoglobin levels on co-oximetry while intubated were measured and dropped to 1.8% within 12 hours. Abnormalities on CBC and CMP resolved within 2 days. He developed paroxysmal atrial fibrillation and required initiation of intravenous diltiazem to control his heart rate. Sedation was slowly weaned off as was ventilatory support, with close monitoring of vitals and ability to follow commands and participate in spontaneous breathing trials. Eventually, he was extubated after 6 days, transitioned to oral diltiazem 30 mg twice daily, and once medically cleared was transferred to the inpatient psychiatric unit.

Figure 1.

Fast spin echo T2 MRI brain. Arrows showing globus pallidus infarcts, left worse than right.

During the psychiatric assessment, he reported his wife was diagnosed with cancer of the intestine around 3 years ago. Lately, her condition worsened, and he got overwhelmed. He reported poor sleep for the last few nights and anxiety, and that he thought of ending his life because he felt that with his life insurance money, his wife would be financially comfortable and perhaps be able to receive better medical care. He reported that when he woke up, he found himself surrounded by his family and people who cared for him. This made him realize that his life was worth living and he regretted attempting suicide. He was thankful to be saved and stated that he would like to live and looked forward to spending time with his wife. He was started on mirtazapine 15 mg at night to help with sleep and anxiety and received supportive therapy while on the unit. During his hospital stay, he reported improvement in sleep and anxiety, and he was able to engage in safety planning. His wife indicated that she felt comfortable and safe taking care of him at home. As a part of his aftercare plan, the patient was connected with outpatient psychiatry and therapy services. The patient and his wife were contacted every 2 weeks over the next 2 months, and they reported that he was doing well. He denied having suicidal ideations or any depression. Furthermore, he conveyed his interest in connecting with local suicide prevention advocacy programs in hopes of using his experience to help others.

Discussion

The patient had anxiety and poor sleep and made a serious suicide attempt of high lethality and strong intent. However, the reason for suicide was not because he was feeling depressed and wanted to end his problems. It was for his wife: he thought that if he ended his life, his wife could get the life insurance money. The patient had an altruistic intention as he cared more deeply for his wife rather than his own life.

Sociologic concepts of suicide

Conventionally, altruistic suicide is conceptualized in terms of cultural context. Suicides were categorized as altruistic by Savage in England in 1892 and the elaboration of the term was by Emile Durkheim in France in 1897. ⁸ Durkheim proposed that the imbalance between social interaction and moral regulation is what leads to suicide. He classified suicide into four types—Altruistic, Anomic, Egoistic, and Fatalistic suicide. According to Durkheim, altruistic suicide occurs when an individual is deeply integrated into society and chooses to sacrifice his own life to benefit other members of society. ⁹

Traditionally the concept of altruistic suicide involves several key features. First, it occurs within a context of abnormally excessive societal integration, where individuals are deeply tied to the rituals and cultural beliefs of a group, leading to a loss of individuality. In other words, they die by suicide for something they value more than their own lives. Second, unlike other types of suicide, it is typically accompanied by public support and approval. Third, altruistic suicide is believed to bring material or cultural benefits to society. Lastly, altruistic suicide is pursued with a psychological state of enthusiasm, in contrast to the melancholic psychological state often associated with egoistic suicides. ¹⁰

Durkheim’s framework of the sociologic concept of suicide differentiated egoistic suicide as the opposite end of the spectrum of societal integration compared to altruistic. He envisioned a U-shaped curve where minimal integration led to a lack of belonging and apathy, increasing the risk of egoistic suicide; a moderate level of integration being protective; and excessive integration led to a lack of value of individual life compared to societal needs, which would be setting for altruistic suicides. He categorized anomic and fatalistic suicide based on levels of societal regulation. Low levels of societal guidance regarding the upper and lower limits of aspirations (a situation that could occur in either an overall downswing or upswing in the resources available to the community) led to an increase in anomic suicides, whereas excessive limitations of the same aspirations (e.g. among prisoners) or significant oppression of a specific group led to what he termed as fatalistic suicides. ¹¹

The key difference between altruistic suicides and non-altruistic suicides rests more in their cultural context: that of high integration where there is little value placed on the life of an individual. ¹⁰

Much of the data underlying the development of these subtypes of suicide came from observation of historical data (for the time) from subsets of populations around the world. For instance, observation of rates of suicide in Vienna in 1870s, in the setting of a financial crash, and in Prussia during 1840s–1850s despite relative affluence led to the theory about anomic suicides; concepts about altruistic suicide were based on descriptions ranging from ancient Danish warriors to Japanese customs. ¹¹ Since then, further research into these concepts has been limited. ¹² In more recent times, there have been cases of patients with COVID-19 who tragically ended their lives to protect their loved ones. ¹³ The cases mentioned occurred during the early stages of the pandemic, at a time when there was no specific treatment or vaccine available. While societal approval of suicide was not the main feature in these cases, it is apparent that those people with COVID-19 sacrificed their lives for the greater benefits or interests of others, their behavior stemming from an excessive state of social integration. ¹³ A similar picture is present in our case, where the patient attempted altruistic suicide, as he valued his wife’s life over him.

Although sociological concepts of suicide in modern societies are not well studied, they can still provide some guidance on suicide prevention strategies. Prevention requires a multifaceted approach as suggested by the Centers for Disease Control. ¹⁴ Some strategies that can help reduce the risk at a community level include promoting a healthy level of social connectedness, reducing the stigma connected to mental health disorders, promoting seeking help for the same, and interventions into economic safety nets such as improving minimum wage levels. ¹²

Clinical aspects of CO poisoning

Clinically, CO poisoning can affect the body in various ways (Table 1).^15–23 As the amount of carboxyhemoglobin increases in our bodies, the physical manifestations of confusion, headaches, weakness, nausea, and shortness of breath manifest. With ongoing exposure without treatment, more severe cardiac and neurologic damage occurs, eventually leading to death. ²⁴ Long-term sequelae of nonfatal CO exposure are the result of damage done at the cellular level. The two main molecular targets that explain the effects of CO toxicity are hemoglobin and the heme a₃ site of cytochrome c oxidase in mitochondria. Formation of carboxyhemoglobin leads to tissue hypoxia via the dual mechanisms of occupation of oxygen-binding sites by CO, and reduced ability of oxyhemoglobin to dissociate to deliver oxygen to tissues. Meanwhile, disruption of the mitochondrial cytochrome system leads to a decreased capacity for energy generation as well as the creation of free radicals, that cause further cellular damage. ²⁵ CO poisoning causes short-term and long-term effects, most readily apparent in the heart and the brain. Cardiac impacts of CO are vast with one out of three poisoned patients experiencing myocardial infarctions, arrhythmias, and/or left ventricular systolic dysfunction. These findings are seen largely in the patients who have had moderate-to-severe exposure to CO. ²⁶ Acute neurologic effects include confusion, stroke-like symptoms, seizures, and in severe cases, coma. Delayed neurologic effects can appear between 2 and 40 days after initial apparent recovery. This happens in about 15%–40% of patients. ²⁶ For example, in a study conducted 33 years after a CO mining accident, MRI scans showed that 72% of the participants had cerebral atrophy, 52.7% of the participants had lacunar infarcts and 37.9% of the participants had pallidum lesions. ²⁷ A vast array of neurologic and/or psychiatric symptoms can develop, including cognitive dysfunction, vestibular dysfunction, mutism, cortical blindness, movement disorders, depression, and anxiety.^25,28,29 Risk factors for increased cognitive impairment include being exposed to CO for a longer period and being over the age of 35. ³⁰

Table 1.

Clinical manifestations of CO poisoning.

System	Potential Clinical Manifestations
Cardiovascular	- Acute and long-term development of myocardial infarction 15 - Reduced left ventricular function 16 - Increased coronary vasoconstriction (due to increase in free radical production) 17 - Stunned myocardium-like syndrome. 18 - Arrhythmias (most common is prolonged QT interval) 19
Neurocognitive	- Vestibular deficits 20 - Motor deficits 20 - Cognitive deficits 20 - Delayed post hypoxic leukoencephalopathy 21
Psychiatric	- Depression 22 - Anxiety 22 - Post-traumatic stress disorder 23 - Impaired memory 22

Fortunately, our patient did not have any major sequelae and reported feeling well upon telephone follow-up 2 months after the exposure.

Conclusion

Suicide attempt by CO poisoning is a highly lethal means to end life, and the benevolent nature of this attempt strongly represents altruistic intentions being the driving force behind such a serious suicide attempt.

In modern times, as families are becoming more nuclear and society places more importance on individual and sense of self-identity, rather than as a part of a bigger community, it is likely that altruistic suicides may not meet all the traditional criteria. More research is needed to redefine sociological theories of suicides keeping in mind societal changes.