Psychiatric Symptoms and Cognitive Appraisal following the Near Sinking of a Research Submarine

Military Medicine, Jan 2005 by Berg, Jennifer S, Grieger, Thomas A, Spira, James L

Objective: This study assessed the stress reactions of a submarine crew forced to abandon their vessel in high seas after flooding and fire damaged their ship. Methods: The remaining crew members (n = 22) were surveyed 7 months after the incident regarding exposures, initial emotional responses, peritraumatic dissociation, subsequent life events, current safety appraisal, and current symptoms of posttraumatic stress disorder (PTSD) and depression. Results: At 7 months, 9.1% met criteria for PTSD and none met criteria for depression. Higher levels of depressive symptoms were associated with previous traumatic exposures, subsequent life events, and higher levels of PTSD symptoms; higher levels of PTSD symptoms were associated with greater peritraumatic dissociation and initial emotional response. Conclusion: Acute exposures of highly trained professionals to potentially fatal events may not result in high levels of posttraumatic symptoms. Previous and subsequent life events may play a more significant role in the level of postdisaster symptoms.

Introduction

Relatively few studies examine psychological reactions to severe traumatic events in individuals trained to respond to potential disasters associated with their occupation.1,2 Multiple studies have assessed rates of posttraumatic stress disorder (PTSD) after prolonged combat.3 However, studies of stress reactions in military members exposed to single, but potentially fatal, accidents during peacetime are limited. The role of previous and subsequent life events on the degree of psychological response to a single accident is also not frequently studied.

U.S. Navy personnel assigned to ships routinely receive specialized disaster response training, such as fire fighting and damage control. Those who work in high-risk environments such as the submarine service are rigorously screened for potential emotional difficulties, are extensively trained in the operating systems of their ships, and routinely practice responses to potential disasters specific to their shipboard environment. Research with this population is very limited, despite the dangers inherent in their operational responsibilities and the potentially hazardous nature of submarine escape procedures.4

Studies of Norwegian, U.S., and South African submarine personnel have indicated that personality traits and/or habitual coping styles may explain how submarine crew members are able to cope with chronic stress inherent to their occupation.5-7 A Norwegian study of three submarine crews exposed to different peacetime maneuver accidents reported more posttraumatic stress symptoms in exposed subjects as compared with nonexposed crew members. The accidents involved collisions while submerged, but the crews did not have to abandon ship.8

Our study focuses on the crew of a U.S. Navy research submarine forced to abandon ship in heavy seas following flooding and shipboard fires. In May 2002, the USS Dolphin was surfaced during training exercises 100 miles off the California coast. The ship was traveling in 11-foot ocean swells when an equipment failure allowed approximately 80 tons of 57°F seawater to enter the crew spaces. Water shorted out electrical equipment, created electrical fires, and caused smoke and toxic fumes to spread throughout the ship. Electrical failures caused pumps to fail. Unable to breathe in the toxic air, the crew was forced to abandoned ship. Some members were swept overboard by high seas and some were in the water for extended periods of time. All members were rescued and medically assessed upon transport to shore. Some suffered from hypothermia and others from minor injuries and were treated acutely. No member required hospitalization and none was noted to have overt psychological symptoms requiring immediate treatment, based upon examination by the medical officer. A group critical incident (CI) debriefing of the crew was held 3 days after the incident, and all crew members attended. The debriefing was typical of what is offered to victims of civilian or medical disasters. No other CI services were performed.

To better understand the effects of this potentially fatal event at sea, we examined history of previous trauma, exposure at the time of the event, peritraumatic dissociation, initial emotional response, subsequent life events, and demographic factors as possible risk factors for PTSD, depression, and attitudes 7 months after the event.

Methods

Subjects

The USS Dolphin had a crew of 44 at the time of the incident. When the ship was returned to port for an extended period of repair, one-half of the crew were reassigned elsewhere based on overall U.S. Navy needs. These reassignments were not based on medical reasons or requests to transfer before the end of a tour. At 7 months following the event, 22 of the original crew remained. After review and approval by the Institutional Review Board, we contacted the remaining crew and offered them the opportunity to participate in the study. To preserve anonymity, the Institutional Review Board waived the requirement for written informed consent. Participants were informed that they might experience emotional difficulties recalling the events of the accident. They were provided several potential referral sources in the event they experienced significant distress. Participants completed the study anonymously on a computer in their work area. Data were collected via Internet transfer and entered into a database for analysis. We received 22 responses, all males. The average age was 29.95 years (SD = 8.13 years), the average length of assignment to the ship was 23.64 (SD = 15.13) months, and duration of active naval service was 10.50 (SD = 7.94) years. Ten (45.5%) individuals were married. The group was predominately Caucasian (n = 16, 72.7%). Most had a high school education or some college credits (n = 20, 90.9%); only one (4.5%) had a college degree, suggesting that approximately 95% were enlisted personnel.