LAUSR

We read with interest the article by Mortensen et al. [1] according to infections in out-of-hospital and in-hospital post-cardiac arrest patients. In this single-center study, the authors reported the microbial profile of infections in postcardiac arrest patients. Here, we would like to share our bacterial profile of infections in the out-of-hospital post-cardiac arrest (OHCA) in our center and discuss the importance of the results. Thammasat University Hospital (TUH) is a 700-bed hospital in Thailand with a 100-bed intensive care facility. We reviewed medical records of the OHCA patients, who were at least 15 years old, admitted to TUH between October 2016 to September 2018. Seventy-five OHCA patients were collected. Three and twenty-seven of them were excluded due to pre-existing infection and admission less than 24-h, respectively. Forty-five remained for analysis, and twentynine of them were treated with TTM. The mean age of the patients in the TTM group was 56.48 ± 15 years, with 75% male. The most common initial rhythm of cardiac arrest was the shockable subtype (47%). The most common cause of arrest was cardiac origin (83%). Seventeen patients in the TTM group developed a nosocomial infection (60%). The most common infection was pneumonia (50%), as shown in Fig. 1b. The most common organisms included Klebsiella pneumonia (56%), Pseudomonas aeruginosa (11%), Escherichia coli (11%), Acinetobacter baumannii (11%), and Staphylococcus aureus (5.5%), respectively (Fig. 1a). The most common antibiotics prescribed for the treatment were piperacillin/tazobactam (43%), ceftriaxone (25%) and ceftazidime (11%), respectively. The Cerebral Performance Category Scale (CPC) of the patients in the TTM group at discharge from the intensive care unit were CPC 5 at 41%, CPC 4 at 28%, CPC 3 at 7%, CPC 2 at 7% and CPC 1 at 17%, respectively. Our data and which reported by Mortensen et al. [1] support the findings from the previous study that pneumonia remains the most common source of infection in post-cardiac arrest patients [2, 3]. Treatment with TTM is an independent risk factor for the occurrence of pneumonia after restored of spontaneous circulation (ROSC) [3]. Pneumonia is also common when TTM is applied for the treatment in other indications outside cardiac arrest [4]. The bacterial profiles reported in our study are contrasted from which of Mortensen et al. [1]. The gram-negative bacteria are the most common pathogens in our study, while, in the study of Mortensen et al. [1], Staphylococcus aureus becomes the most common one. This phenomenon may reflect the geographic effect on the nature of the bacterial infection. The microbial profile of infection in post-cardiac arrest should be individually unique for each center. The bacterial profile is essential for appropriate choices of the antibiotic treatment. The antibiotic prophylaxis may lower the incidence of pneumonia in post-cardiac arrest [5]. The antibiotic used for the prophylactic treatment must cover the potential pathogens. The best choice of antibiotic prophylaxis should depend on the bacterial profiles in each center. We suggest that each center should collect individual bacterial profile to use as the data for the most appropriate choice of antibiotic prophylaxis in post-cardiac arrest.