Counteraction of early circulatory derangement by administration of low dose steroid treatment at the onset of established endotoxemic shock is not directly mediated by TNF-α and IL-6

ACETAMINOPHEN ATTENUATES PULMONARY VASCULAR RESISTANCE AND PULMONARY ARTERIAL PRESSURE AND INHIBITS CARDIOVASCULAR COLLAPSE IN A PORCINE MODEL OF ENDOTOXEMIA

ABSTRACT

Acetaminophen (paracetamol) is often used in critically ill patients with fever and pain; however, little is known about the effects of acetaminophen on cardiovascular function during systemic inflammation. Here, we investigated the effect of acetaminophen on changes in the systemic and pulmonary circulation induced by endotoxin (0.5 μg/kg per hour) in anesthetized pigs. Endotoxin infusion led to a rapid increase in pulmonary artery pressure and pulmonary vascular resistance index. Acetaminophen delayed and attenuated this increase. Furthermore, acetaminophen reduced tachycardia and decreased stroke volume, accompanied by systemic inflammation, without affecting inflammatory parameters such as white blood cell count and TNF-α in blood. As a proof of concept, we injected a high dose of endotoxin (100 μg), which induced rapid cardiovascular collapse in pigs. Pigs treated with acetaminophen survived with no obvious hemodynamic instability during the 50-min observation period. In conclusion, acetaminophen attenuates the effects of endotoxin on pulmonary circulation in anesthetized pigs. This may play a role in severe systemic inflammation.

Postarrest Steroid Use May Improve Outcomes of Cardiac Arrest Survivors

OBJECTIVES

To evaluate the ramifications of steroid use during postarrest care.

DESIGN

Retrospective observational population-based study enrolled patients during years 2004-2011 with 1-year follow-up.

SETTING

Taiwan National Health Insurance Research Database.

PATIENTS

Adult nontraumatic cardiac arrest patients in the emergency department, who survived to admission.

INTERVENTIONS

These patients were classified into the steroid and nonsteroid groups based on whether steroid was used or not during hospitalization. A propensity score was used to match patient underlying characteristics, steroid use prior to cardiac arrest, the vasopressors, and shockable rhythm during cardiopulmonary resuscitation, hospital level, and socioeconomic status.

MEASUREMENTS AND MAIN RESULTS

There were 5,445 patients in each group after propensity score matching. A total of 4,119 patients (75.65%) in the steroid group died during hospitalization, as compared with 4,403 patients (80.86%) in the nonsteroid group (adjusted hazard ratio, 0.74; 95% CI, 0.70-0.77; p < 0.0001). The mortality rate at 1 year was significantly lower in the steroid group than in the nonsteroid group (83.54% vs 87.77%; adjusted hazard ratio, 0.73; 95% CI, 0.70-0.76; p < 0.0001). Steroid use during hospitalization was associated with survival to discharge, regardless of age, gender, underlying diseases (diabetes mellitus, chronic obstructive pulmonary disease, asthma), shockable rhythm, and steroid use prior to cardiac arrest.

CONCLUSIONS

In this retrospective observational study, postarrest steroid use was associated with better survival to hospital discharge and 1-year survival.

The impact of hydrocortisone treatment on neutrophil gelatinase-associated lipocalin release in porcine endotoxemic shock

Background

A key feature of sepsis is systemic inflammatory activation that could be counteracted by steroids. In this experimental model of systemic inflammation, we sought to investigate whether septic neutrophil activation, evaluated by the plasma levels of neutrophil gelatinase-associated protein (NGAL), is modulated by the timing of hydrocortisone treatment.

Methods

Sixteen anesthetized pigs were allocated to one of four equally sized groups. Three of these groups received endotoxin at 2 μg × kg⁻¹ × h⁻¹ for 6 h so as to induce endotoxemic shock. Hydrocortisone (5 mg × kg⁻¹) was administered intravenously before endotoxemic challenge, or at the onset of endotoxemic shock. Endotoxemic pigs not receiving hydrocortisone and non-endotoxemic pigs served as control groups. Physiologic variables, hematology, and biochemistry, including plasma NGAL, were measured repeatedly.

Results

Hydrocortisone treatment prior to endotoxemia attenuated some inflammatory, hematological, circulatory, and metabolic manifestations of shock (i.e., higher white blood cell count, higher mean arterial pressure, lower heart rate and mean pulmonary arterial pressure, higher left ventricular stroke work index, higher base excess). Endotoxemic shock increased plasma NGAL (p < 0.001). In pigs given hydrocortisone before the endotoxin infusion, plasma NGAL was lower as compared to those given hydrocortisone at endotoxemic shock (p < 0.05). Plasma NGAL levels correlated inversely to neutrophil granulocyte counts (rho = −0.65) but not to urine output (rho = −0.10) at the end of the experiment.

Conclusions

The increase in plasma NGAL is counteracted by hydrocortisone administration prior to endotoxemia; concomitantly, this treatment was associated with less expressed circulatory derangement. Urine NGAL did not differ between the groups, suggesting that the NGAL response was not primarily related to kidney injury.

Low-Dose Steroid Therapy Is Associated with Decreased IL-12 Production in PBMCs of Severe Septic Patients

Background. Sepsis-induced immunosuppression may result in higher mortality rates in patients. Methods. We examined the relationship of cytokine responses from stimulated peripheral blood mononuclear cells (PBMCs) and monocyte human leukocyte antigen-DR (HLA-DR) expression (days 1 and 7) with low-dose steroid therapy in 29 septic patients. Patients were treated according to the guidelines. Thirty healthy controls were enrolled for validation. Results. Eighteen patients were prescribed low-dose steroids and 11 were not. Interleukin- (IL-) 12 responses in patients without low-dose steroid therapy on days 1 and 7 were higher than those with low-dose steroid therapy. Compared to day 1, IL-12 responses significantly increased on day 7 in patients without low-dose steroid therapy. After regression analysis, the change in the IL-12 response from day 7 to day 1 was found to be independently associated with the low-dose steroid therapy. There was no difference in monocyte HLA-DR expression between patients treated with and without low-dose steroid on day 1 or 7. No change in monocyte HLA-DR expression from day 7 to day 1 was observed in patients with or without low-dose steroid therapy. Conclusion. Decreased IL-12 response was associated with the low-dose steroid therapy in PBMCs of septic patients.