Approximately 6% of the adult population in the United States suffers from posttraumatic stress disorder (PTSD), and nearly 15 million new cases are reported each year.1 Posttraumatic stress disorder is a complex clinical condition that can severely impair a patient’s recovery from acute or critical illness and involves poor physical function and quality of life after hospitalization. Because of the complexity of its clinical presentation and its multiple etiologic and risk factors, PTSD is often unrecognized by health care professionals—including nurses and advanced practice registered nurses (APRNs)—without a formal educational and training background in the diagnosis and management of patients with PTSD. In acute and critical care units, patients are typically admitted for nonpsychiatric diagnoses; therefore nurses and APRNs may be unaware that the illness and hospitalization experience per se are forms of traumatic events and risk factors for developing PTSD.2 This article aims to increase awareness about PTSD in the acute and intensive care unit (ICU) settings by offering APRNs foundational and updated knowledge about PTSD, as well as exploring PTSD’s implications for practice.PTSD was described in the United States after the First World War as “shell shock,” as “nostalgia” by the Swiss, and even more nondescriptively, as “not yet diagnosed, nervous” or mental defect by the British.3 As a defined condition, PTSD came about largely in response to the need to classify large numbers of Vietnam War veterans who had complex presentations of psychiatric symptoms; the term first appeared the Diagnostic and Statistical Manual, Third Edition (DSM-III), published in 1980.4 Diagnostic criteria for PTSD were first presented in the DSM-III and were refined in later editions to a more specific identification of symptomology. Despite these advancements in defining PTSD, much remains unknown including the best assessment techniques.Among the fears that health care professionals have about addressing mental health issues in patients are “not knowing the right thing to say,” saying the wrong thing, or making an incorrect diagnosis. For the treatment of PTSD, recognizing symptoms and screening for referral is the first critical step in the process of recovery. An emerging approach is to use symptom science, which provides a coherent guide for health care professionals, including nonpsychiatric nurses, to strategically approach the condition in the absence of an accurate diagnosis.Because of the complexity of PTSD, it is best to understand it from a symptom science perspective. Symptom science focuses on symptom experiences and their biological underpinnings, rather than on diseases and illnesses, with the understanding that many symptoms are shared across ailments.5 Symptom science is increasingly important as people are living longer with multiple chronic illnesses. This approach is particularly helpful for the diagnosis and treatment of PTSD. Because there currently are no definitive interventions or medications approved by the US Food and Drug Administration (FDA) to treat PTSD, a symptom science approach can provide a framework aimed at addressing symptoms that that can provide relief for people diagnosed with PTSD. Additionally, many individuals who have experienced trauma do not meet diagnostic criteria for PTSD but suffer debilitating effects of clustered and related symptoms as outlined in the Table.6 Notably, patients in ICUs can suffer from acute biologic crises—including but not limited to brain injuries, cardiac arrests, and multiple postoperative complications—and can manifest psychiatric symptoms but not meet the diagnostic criteria summarized in the Table.To receive a diagnosis of PTSD, individuals must report symptoms identified within 4 defined “symptom clusters” (Table), with at least 1 symptom from the intrusive thoughts and avoidance clusters and at least 2 symptoms each from negative thoughts and feelings and arousal and reactive symptoms. Symptoms are experienced for more than 1 month resulting in distress or functional impairment and are not the result of medication, substance use, or physical illness.7 The criterion standard for diagnosing PTSD is a structured clinical interview such as the Clinician Administered PTSD Scale (CAPS).8 This is conducted by a trained mental health provider to make a formal assessment of and possible diagnosis for PTSD. The CAPS was updated to reflect the corresponding changes made to the DSM-5 for diagnosis of PTSD and is referred to as CAPS-5.The DSM-5 provided further clarification in its 2013 update; most significant was the removal of the subjective component to the definition of trauma. Research has guided this process by exploring the biological basis of PTSD. There is emerging evidence to support both the structural and functional changes in the brain following exposure to a traumatic event. These changes present as both physical as well as mental health symptoms (Table).9 It is this guidance that APRNs can use to provide clarity and understanding to patients in order to facilitate accurate and timely diagnosis, particularly for individuals with a history of traumatic exposure, such as being defibrillated and/or cardioverted while awake.Understanding the symptoms associated with a PTSD diagnosis can also help the APRN develop a differential diagnosis. An important part of the assessment is understanding the patient’s experience and interpretation of the traumatic event, which is a part of the criterion for PTSD diagnosis. For example, if a patient is too unstable to receive sedation prior to receiving cardioversion, it is important to consider the patient’s experience. There are likely several health care team members surrounding the patient, and actions such as giving verbal orders can be misinterpreted. Furthermore, the pain of the shock delivered could be perceived by the patient as a serious injury or exposure to death, when in fact it is a lifesaving procedure. Providing sedation after the shock can provide retrograde amnesia, which is also similar to the criteria of not being able to remember important aspects of the event. Interventions such as these may not meet the level of severity or type of stressor required for a diagnosis of PTSD, and the patient may only meet a few of the diagnostic criteria.In other cases, a patient may meet criteria for PTSD, but the symptoms are time-limited to 3 days to 1 month following exposure. There are several other symptom presentations that are similar to a PTSD diagnosis and should be considered when determining a differential. Other symptoms to be aware of include anxiety, depression, interpersonal difficulties, and perceptual disturbances. The APRN should refer to the Figure for best practices when caring for a patient who has recently experienced a traumatizing medical procedure. It is important to not only identify patients with symptoms (positive screen) but to be able to educate them about the symptoms they are experiencing. An appropriate referral to a mental health specialist will allow for the differentiation between a positive screen and a PTSD diagnosis.A patient’s symptom profile is unique and does not always meet the criteria of PTSD at a given moment in care. However, the acute and critical care environment can contribute to the stress response of the patient; patient behaviors in this environment that could raise the possibility of a PTSD diagnosis can include startling in response to loud noises or hyper-vigilance in the busy milieu. Another indication of PTSD is a response of aggression or anger in situations in which a patient may feel that they are being treated unfairly or where they are stressed. This can strain the relationship between the patient and health care team, impacting the care being provided and potentially leading to poor outcomes. Care received in the acute care setting can leave a lasting impact on a patient. Restraints or sedation can leave a patient feeling trapped, and procedures, such as urinary catheterizations, can be perceived as a sexual assault.Timing is important when considering a patient who has had an ICU admission. Research is beginning to show that this group of patients are at an increased risk for PTSD. Multiple experiences while in the ICU, such as confronting one’s mortality, delirium and psychosis, and the possibility of witnessing the death of others on the unit, are just a few examples of potentially traumatic experiences.10 Ongoing focus on the physical and/or physiological needs of a patient post-ICU admission can further delay a screen and accurate diagnosis of PTSD. An APRN can advocate for timely intervention by understanding not only the impact of such an admission but also that a preexisting anxiety disorder can place a patient at increased risk.10During the hospitalization period, symptom screening can and should be done by a health care provider (eg, APRNs, physicians) as a part of routine care. The burden of identifying an accurate correlation of symptom presentation to a diagnosis should not be left to an individual’s ability to identify and disclose symptoms posthospitalization. Although a minimum of 1 month after exposure to a traumatic experience must pass before the clinical diagnosis of PTSD can be made,7 the recommended approach of routine screening can lead to earlier identification of symptoms and referral to mental health providers. This represents health promotion in the purest sense and the practice of appropriate preventive care after hospitalization.Treatment for PTSD has been traced as far back as the fifteenth century, when it was theorized that a “stone of madness” in a patient’s head could cause madness, idiocy, or dementia. Surgical removal of this stone, a crude procedure indeed, foreshadowed the philosophical and neurobiological underpinnings of the disorder and the advancement of treatment interventions.11 Understanding that there is a neurobiological basis for PTSD helps to make logical sense of symptom presentation and allows for the ability to practice precision medicine and the selection of treatment tailored to an individual’s symptom profile. There is still much to be understood about PTSD, however similar evidence of a neurobiological basis exists in the other mental health disorders, including depression12 and schizophrenia,13 where selected classes of medications are proven efficacious to alleviate a chemical imbalance. A targeted symptom-management prescribing approach is something APRNs can offer, allowing for patient input to address symptoms that are most bothersome.The goal with a preventative health approach is to minimize the number of people progressing to needing aggressive treatment. One example of a preventative approach is a 5-week rehabilitation program developed for discharged ICU patients called InS:PIRE (Intensive Care Syndrome: Promoting Independence and Return to Employment).14 Posttraumatic stress disorder after an ICU admission is common because of altered memories developed during their stay. This program helps patients recreate the narrative by incorporating ICU diaries that are completed by providers and family members, allowing patients to understand that disturbing memories are not real.14 Outcomes show significant improvements after ICU discharge. Health utility scores improved more after 1 year versus those of a historical control group. This cohort had more than 88% of patients return to work or volunteer roles compared with only 46% in the historical control group.14APRNs should be aware of the options available to help patients make informed decisions about the risks and benefits of certain treatments. In the absence of FDA-approved medications for the treatment of PTSD, symptom science allows treatment of symptoms related to PTSD; the most successful interventions involve therapeutic modalities. Current pharmacological interventions include the off-label use of prazosin for nightmares and the antidepressants sertraline, paroxetine, fluoxetine, and venlafaxine.15 Medications can reduce the symptoms of PTSD and improve functioning, but they do not eliminate symptoms entirely. Eye movement desensitization and reprocessing (EMDR) is a psychotherapy centered around working on traumatic memories and the associated stress symptoms. Another psychotherapy commonly used is cognitive behavioral therapy (CBT), which is short-term, problem-focused, and readily manualized for teaching and dissemination. The goal of CBT would be to help with cognitive distortions that may arise from traumatic experiences. The inclusion of an interdisciplinary team to guide the discharge process is critical to establish referrals including appropriate psychotherapy services.As is the case with treatments for other mental and physical chronic illnesses, PTSD treatments are expanding, including pharmacological and nonpharmacological interventions. Stellate ganglion block (SGB) may have short-term benefit for some individuals with PTSD. However, it is not an established treatment at this time because the evidence is not conclusive, although researchers reported improvement of 10 or more points on mean CAPS-5 total symptom severity scores from baseline to 8 weeks.16 Best practice guidelines recommend use of psychotherapeutic approaches for the management of PTSD.17 However, for some patients, chronic PTSD and comorbid mental and physical illnesses become debilitating. In these patients, timely consideration of novel treatment approaches for the management of PTSD can be beneficial.One avenue of novel treatment for PTSD is the use of psychedelics, a growing and rapidly evolving field of treatment for mental illness.18 Psychedelics used include 3,4-methylene dioxymethamphetamine (MDMA), ketamine, lysergic acid diethylamide (LSD), and psilocybin. Although the mechanism of action for each is different, and there are few well-designed clinical studies, the results for treatment of PTSD are promising.18 These substances are given during sessions of psychedelic-assisted psychotherapy (PAP). Patients receiving a psychedelic are guided through the process with a trained mental health professional. Listening to music during the sessions, recipients are encouraged to remain introspective and open to thoughts, feelings, or memories that may arise. Psychedelic-assisted psychotherapy is starting to show promising results in the treatment of PTSD.19The acute or critical care APRN will have an important role in recognizing, screening, and referring patients for an early diagnosis that may lead to prevention and appropriate management.Posttraumatic stress disorder is complex, with diagnostic criteria that have evolved over time as we have developed better understanding of predisposing risk factors, symptom clusters, and targeted interventions. Its complexity has often made it difficult for APRNs outside the mental health field to diagnose and treat it effectively. Lending to this difficulty are the many symptoms of PTSD that may mimic medical complications, such as delirium, or that may go unrecognized. In addition, certain interventions in the acute care setting may constitute a traumatic event for a patient and predispose them to PTSD. The goal is to increase awareness about PTSD in the acute ICU settings, including offering APRNs foundational and updated knowledge about PTSD. With this knowledge, providers will be able to identify patients who may be at risk for developing PTSD, intervene and refer early, and reverse the negative effects of PTSD on health and quality of life.