The Case for the Case

The popular television series Downton Abbey recently concluded after six seasons of being viewed in the UK, United States and other parts of the world. This award-winning series told a story of a fictional aristocratic British family and their domestic servants in the post-Edwardian era in Yorkshire. The series was set in the early twentieth century and follows the trials and tribulations of the family as the world emerges from World War I and into the 1920s. Over the six seasons, the story line has had its share of love, lust, violence, justice and, most important of all, controversy and the challenges related to change. Although fictitious, Downtown Abbey tells a “story”. In scientific endeavors, non-fictional events are also described in many forms, one being the case report. A case study identifies a person, a problem, a setting, a treatment or intervention and some form of finality; if a similar case has been previously published, the current one being reported can easily be put in context. In some situations, the ending is rewarding, happy and positive; in other situations, it is sad, disappointing or unsuccessful. Often, a case study identifies a unique clinical problem or challenge which, in some forms, may be a rare event. Often, the clinical problem is a mystery. The problem may even be undiagnosed pathophysiology and the treatment may be vague or inconclusive. However, these individual case studies typically identify the need for further research and investigation on the clinical problem or issue. Research purists might argue that case studies are not overly valid because it is difficult to make a generalized conclusion in a single setting. Controlled, randomized, blinded studies might be the best form to study any scientific hypothesis, yet these studies are often difficult to control and involve many patients, thus, are expensive to conduct and analyze; because of these constraints, they cannot be reported as quickly as a case report. Prospective studies with designated experimental cohorts with measureable variables and statically comparable groups are often used to test a hypothesis in a controlled setting. However, these studies often fall short of proving their hypothesis for they often require a large study population number to suggest a conclusion or advantage. Small pilot studies are just that: small. Pilot studies can be used to show proof of concept, but it can be a stretch to make any widespread clinical conclusion on an n=5. The question arises if a single case study or even a small cohort study has any validity. The single case report does identify a unique problem, a method of interaction and a result. Often, the most meaningful case studies are those that are unsuccessful, but raise questions that usually lead to even more challenges. In this issue of Perfusion, in addition to the regular collection of scientific publications, there are three case studies that cover three unique topics. The first by Benetis et al. describes the ECMO course of an 18-yearold woman who developed sepsis, respiratory distress and disseminated intravascular coagulation postpartum after an urgent C-section. Swol et al. report on the use of ECMO support after trauma with an associated finding of open tuberculosis. The third case study by Tran et al. describes the operative management of a HeartMate II (HMII) left ventricular assist device in a patient with a non-compliant left ventricle and a reduced right ventricular end-diastolic volume. As a result of the surgical procedure, the right and left ventricular stroke volumes were different, resulting in an inaccuracy in the HMII flow rate display. Certainly, in each of these cases, the problem or occurrence is rare, yet each report gives clinician readers an insight on optional treatments and raises questions that may be grounds for further study. In summary, case reports are a time-honored tradition in medicine aimed at better patient care and, as such, they constitute an important part of the published literature embodied in our journal.