Sub-anesthetic Intravenous Ketamine Infusion on Behavior, Biomarkers, and Fear Memory in Male Sprague-Dawley Rats

THE PROBLEM

Ketamine is a multimodal dissociative anesthetic and potent analgesic administered to the combat wounded service members following traumatic injury. Since ketamine induces transient psychosis effects, there are concerns regarding its impact on the development of stress related disorders.

A limited number of pre-clinical rodent investigations have looked at the effects of post-fear conditioning of ketamine on fear memory and PTSD-like behaviors, and no pre-clinical investigations have administered post-fear conditioning ketamine intravenously (i.v.), a more clinically relevant route of administration, to rodents to measure outcomes on fear memory behavior and brain activity.

OUR APPROACH

We conducted a series of prospective, randomized pre-clinical investigations to explore effects of sub anesthetic ketamine infusions on dissociative behavior, fear memory, stress biomarkers, and brain region activation. First, we administered varying dosages of i.v. ketamine infusions and measured peak serum ketamine concentrations and effects on dissociative behaviors to determine effective i.v. dosages. Using these dosages, we administered i.v. ketamine infusions to male rats following a fear conditioning paradigm and measured effects on fear memory behaviors and serum biomarkers of stress. Lastly, we administered an i.v. ketamine infusion following fear conditioning and measured effects on brain region activation.

 

Graduate School of Nursing

 

Graduate School of Nursing

 

RESULTS

Our results suggest that a sub-anesthetic ketamine i.v. infusion administered immediately following trauma enhances fear memory and activates brain regions associated with fear and stress.

We found that when sub anesthetic i.v. ketamine was administered by infusion to male rats, there are dose-dependent enhancements to fear behavior, corticosterone biomarkers, and increased brain activity in regions associated with fear and stress. These results suggest that sub-anesthetic ketamine following traumatic injury may enhance fear memory and contribute to symptoms of acute stress disorder.

FUNDING

Tri-Service Nursing Research Program, Jonas Foundation, and Uniformed Services University Intramural Support.

 

 

“The PhD program of study emphasizes science, leadership, and research focused on advancing the science of military and federal health care.”

MARY B. ENGLER, PHD, RN, MS, FAHA
PROFESSOR & CHAIR/DIRECTOR, PHD PROGRAM IN NURSING SCIENCE

A Network Analysis of Perioperative Communication Patterns in a Military Medical Setting

THE PROBLEM

The quality of interpersonal and team communication is widely recognized as a factor that affects overall safety, performance, and degree of innovation. This study used social network analysis to characterize the typical operating room communication patterns of clinicians at a military hospital and determine how their interdependent relationships influenced communication.

OUR APPROACH

A multilevel approach was used to examine clinician communication on the personal, dyadic, and whole network levels. A sociometric survey consisting of six networks (advice-giving, advice-seeking, interaction, socialization, close working relationship, and voice) was compared with communication effectiveness ratings to determine the structural aspects of the OR communication network.

Graduate School of Nursing

 

Graduate School of Nursing

 

RESULTS

Communication effectiveness increased in networks in which OR team members reported interacting frequently, having close working relationships, socializing, and seeking/giving advice.

The findings of this study highlight the complexity of human interaction. High network communication effectiveness was associated with increased network density and anesthesia providers and perioperative nurses had the (first and second) highest communication effectiveness ratings among all OR team members.

Interaction frequency, team familiarity, and team performance are measures that administrators should consider when assigning surgical team members to cases.

FUNDING

Tri-Service Nursing Research Program (TSNRP) and the Jonas Foundation