Peritoneal Dialysis in Dengue Shock Syndrome May Be Detrimental

Dengue shock syndrome is the most severe form of Dengue that can be fatal. Nonresponders to standard therapy need intensive care. This paper outlines the clinical features, complications, and outcomes of Dengue Shock Syndrome not responding to standard therapies and needing supportive care in a tertiary referral intensive care unit of a developing country. Nearly one-third die within 3 days of admission to ICU. Peritoneal dialysis predicts the worst outcomes

Oxygen Delivery and Oxygen Consumption in Pediatric Fluid Refractory Septic Shock During the First 42 h of Therapy and Their Relationship to 28-Day Outcome

Background: In septic shock, both oxygen delivery (DO2) and oxygen consumption (VO2) are dysfunctional. The current therapeutic regimens are geared to normalize global oxygen delivery (DO2) to tissues via goal directed therapies but mortality remains high at 10–20%.Methods: We studied cardiac index (CI), systemic vascular resistance index (SVRI), central venous oxygen saturation (ScvO2), central venous pressure (CVP), peripheral oxygen saturation (SpO2), mean blood pressure (MBP), body temperature, blood lactate, base excess and hemoglobin concentration (Hb) in a cohort of children admitted in “fluid-refractory” severe septic shock to pediatric intensive care, over 4.5-years. We calculated their 6 h global oxygen delivery (DO2) and global oxygen consumption (VO2) over the first 42 h and looked at factors associated with VO2/DO2 ratio (i.e., global oxygen extraction, gO2ER) and 28-day mortality.Results: Sixty-two children mean age (SD) 7.19 (5.44) years were studied. Fifty-seven (93%) children were sedated and mechanically ventilated and all received adrenaline or noradrenaline or both and added milrinone in 6 (9.6%). At 28 days, 9 (14.5%) were dead. The global oxygen extraction ratio (gO2ER) was consistently lower amongst the survivors and independently predicted mortality (ROC AUC = 0.75). A lactate level of 4 mmol/l or above, when associated with a concurrent metabolic acidosis predicted mortality with a sensitivity of 100% (95% CI 90.5–100) and a specificity of 67.7% (95% CI 62.2–72.9). A gO2ER of 0.48 or above on admission to the PICU was associated with death with a 66.7% sensitivity (95%CI 29.9–92.5) and 90.5% specificity (95%CI 79.3–96.8). A global O2ER of >0.48 combined with a concurrent blood lactate >4.0 mmol/l at any time within the first 42 h of therapy predicted death with a sensitivity of 63.9% (95% CI, 46.2–79.1) and specificity of 97.8% (95% CI, 95.7–99.0). A radar plot identified MBP-CVP difference, and CI as additional goals of therapy that may offer a survival benefit.Conclusions: Global O2ER of >0.48 with a concurrent blood lactate >4.0 mmol/l in children with metabolic acidosis was an independent factor associated with death in fluid resistant septic shock. Trends of gO2ER seem useful to recognize survivors and non-survivors early in the illness

Clinical Study Peritoneal Dialysis in Dengue Shock Syndrome May Be Detrimental

Dengue shock syndrome is the most severe form of Dengue that can be fatal. Nonresponders to standard therapy need intensive care. This paper outlines the clinical features, complications, and outcomes of Dengue Shock Syndrome not responding to standard therapies and needing supportive care in a tertiary referral intensive care unit of a developing country. Nearly one-third die within 3 days of admission to ICU. Peritoneal dialysis predicts the worst outcomes

The role of nitric oxide in childhood hypertension and a critical analysis of the measurement and interpretation of blood pressure

Nitric oxide, synthesised continuously from the amino acid L-arginine by the constitutive nitric oxide synthase enzyme of the vascular endothelium maintains a constant vasodilator tone. This basal release of nitric oxide, that help maintains blood pressure at normal level, was believed to be diminished in adults with essential (primary) hypertension but no data was available on its role in childhood hypertension. Raised plasma levels of naturally occurring nitric oxide synthase inhibitors (arginine analogues) had been identified in some cases of pregnancy induced hypertension and in renal failure but their physiological importance was uncertain. Experimentally, however, oral administration of nitric oxide inhibitors was known to produce hypertension. The initial investigations described in Part A of this thesis demonstrate raised plasma levels of arginine analogues, particularly asymmetric dimethyl arginine (ADMA) in children with hypertension. Subsequent experiments in vitro on mice aortic rings confirm that the concentrations of ADMA detected in human plasma may be sufficient to cause an alteration in vascular tone, hence blood pressure. Although a concomitant reduction in nitric oxide generation was expected in these subjects, its assessment indirectly by estimating plasma levels of nitrate appear to suggest otherwise. Additionally higher levels of plasma ADMA was associated with a lower plasma renin activity in these subjects, a possible but hitherto unknown negative feed back mechanism for renin dependent blood pressure control. Furthermore, raised levels of ADMA were shown to be associated with raised plasma levels of the adhesion molecule VCAM-1, a known intermediary in the development of atheroma. This may have wider implications in terms of the development of atheroma in other conditions with raised plasma arginine analogues. Despite the known influence of these plasma agents on blood pressure, none correlated with blood pressure itself in these subjects. On investigation of this observation, a second theme evolved; i.e. factors causing errors in interpretation of blood pressure and its measurement. This is described in Part B that includes a critical analysis of current approved methods of blood pressure measurement and clinical validation of new blood pressure monitors for use in children. This thesis therefore provides the first insight into the role of nitric oxide, in particular its inhibitor ADMA in childhood hypertension especially in the presence of renal impairment. This molecule is at least likely to be involved in modulation of renin angiotensin system and endothelium mediated complications such as atheroma in hypertensive children, besides its prominent role in altering vascular tone and natriuresis. Demonstration of a link between ADMA and blood pressure itself in vivo, however, is difficult due to the complexity of the cardiovascular regulation and covert errors in blood pressure measurement and interpretation

Arterial and end tidal carbon dioxide difference in pediatric intensive care

BACKGROUND AND AIM: Arterial carbon dioxide tension (PaCO(2)) is considered the gold standard for scrupulous monitoring in pediatric intensive care unit (PICU), but it is invasive, laborious, expensive, and intermittent. The study aims to explore when we can use end-tidal carbon dioxide tension (P(ET)CO(2)) as a reliable, continuous, and noninvasive monitor of arterial CO(2) MATERIALS AND METHODS: Concurrent P(ET)CO(2), fraction of inspired oxygen, PaCO(2), and arterial oxygen tension values of clinically stable children on mechanical ventilation were recorded. Children with extra-pulmonary ventriculoatrial shunts were excluded. The P(ET)CO(2) and PaCO(2) difference and its variability and reproducibility were studied. RESULTS: A total of 624 concurrent readings were obtained from 105 children (mean age [SD] 5.53 [5.43] years) requiring invasive bi-level positive airway pressure ventilation in the PICU. All had continuous P(ET)CO(2) monitoring and an arterial line for blood gas measurement. The mean (SD) number of concurrent readings obtained from each child, 4-6 h apart was 6.0 (4.05). The P(ET)CO(2) values were higher than PaCO(2) in 142 observations (22.7%). The PaCO(2)–P(ET)CO(2) difference was individual admission specific (ANOVA, P < 0.001). The PaCO(2)–P(ET)CO(2) difference correlated positively with the alveolar-arterial oxygen tension [P(A-a)O(2)] difference (ρ = 0.381 P < 0.0001). There was a fixed bias between the P(ET)CO(2) and PaCO(2) measuring methods, difference +0.66 KPa (95% confidence interval: +0.57 to +0.76). CONCLUSIONS: The PaCO(2)–P(ET)CO(2) difference was individual specific. It was not affected by the primary disorder leading to the ventilation