Esophageal echo-Doppler monitoring in burn shock resuscitation: are hemodynamic variables the critical standard guiding fluid therapy?

Volume Resuscitation in Patients With High-Voltage Electrical Injuries

Volume resuscitation of patients with high-voltage electrical injuries (>1000 V) is a more complex challenge than standard burn resuscitation. High voltages penetrate deep tissues. These deep injuries are not accounted for in resuscitation formulae dependent on percentage of cutaneous burn. Myonecrosis occurring from direct electrical injury and secondary compartment syndromes can result in rhabdomyolysis, compromising renal function and urine output. Urine output is the primary end point, with a goal of 1 mL/kg/h for adult patients with high-voltage electrical injuries. As such, secondary resuscitation end points of laboratory values, such as lactate, base deficit, hemoglobin, and creatinine, as well as hemodynamic monitoring, such as mean arterial pressure and thermodilution techniques, can become crucial in guiding optimum administration of resuscitation fluids. Mannitol and bicarbonates are available but have limited support in the literature. High-voltage electrical injury patients often develop acute kidney injury requiring dialysis and have increased risks of chronic kidney disease and mortality. Continuous venovenous hemofiltration is a well-supported adjunct to clear the myoglobin load that hemodialysis cannot from circulation.

The Variation of Hemodynamic Parameters Through PiCCO in the Early Stage After Severe Burns

To investigate early hemodynamics of severely burned patients via PiCCO and to discuss clinical significance of hemodynamic monitoring for burn shock resuscitation, 55 extensive burn patients were enrolled in this retrospective study. The fluid resuscitation was guided according to Chinese General Formula and adjusted with urinary output of 0.5-1.0 ml/h/kg as a resuscitation goal. All patients were diagnosed within a relatively stable condition during burn shock stage, and they received PiCCO monitoring within 6 hours after burn. The preload parameter intrathoracic blood volume index was low at first, then returned to normal. The flow parameter cardiac index and myocardial contractility parameter dPmax were gradually changed from low level in the early stage to high level in the fluid reabsorption stage. The afterload parameter systemic vascular resistance index had completely opposite tendency. The lung-related parameters extravascular lung water index and pulmonary vascular permeability index were roughly in the normal range. The change of cardiac index had a linear regression relationship with dPmax and systemic vascular resistance index but had no significant relationship with intrathoracic blood volume index. Under effective fluid resuscitation, the early hemodynamics after burn is still in dynamically changing status, characterized as transition from low cardiac output (CO)-high vascular resistance in early shock stage to high CO-low vascular resistance in fluid reabsorption stage. CO mainly depends on the myocardial contractility and vascular resistance, but not on the blood volume. Excessive fluid resuscitation cannot get normal CO. The normal value of hemodynamics cannot be used as end point of burn shock resuscitation. Dynamic observation of hemodynamics is of great importance.

Fluid resuscitation management in patients with burns: update

Since 1968, when Baxter and Shires developed the Parkland formula, little progress has been made in the field of fluid therapy for burn resuscitation, despite advances in haemodynamic monitoring, establishment of the 'goal-directed therapy' concept, and the development of new colloid and crystalloid solutions. Burn patients receive a larger amount of fluids in the first hours than any other trauma patients. Initial resuscitation is based on crystalloids because of the increased capillary permeability occurring during the first 24 h. After that time, some colloids, but not all, are accepted. Since the emergence of the Pharmacovigilance Risk Assessment Committee alert from the European Medicines Agency concerning hydroxyethyl starches, solutions containing this component are not recommended for burns. But the question is: what do we really know about fluid resuscitation in burns? To provide an answer, we carried out a non-systematic review to clarify how to quantify the amount of fluids needed, what the current evidence says about the available solutions, and which solution is the most appropriate for burn patients based on the available knowledge.

Effects of fluid resuscitation methods on the pro- and anti-inflammatory cytokines and expression of adhesion molecules after burn injury

Fluid resuscitation management can influence inflammatory response after burn injury. The aim of this study was to analyze the effects of two fluid resuscitation methods on the cytokine production and on the expression of the leukocyte surface markers. Thirty patients were included in this prospective randomized study with burn injury affecting more than 20% of the body surface area. Fluid resuscitation was guided by hourly urine output (HUO, n = 15) or by intrathoracic blood volume index (ITBVI, n = 15). Blood samples were taken on admission and on the next five consecutive mornings. Concentrations of interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12p70, and tumor necrosis factor-alpha were measured in phorbol myristate acetate-stimulated and -nonstimulated samples. Leukocyte surface marker expressions (CD11a, CD11b, CD14, CD18, CD49d, and CD97) were also determined. In the ITBVI group, IL-6 levels on days 2 to 3 and IL-6/IL-10 ratios on days 2 to 3, and the IL-8/IL-10 ratios on days 3 to 5 were significantly higher than those in HUO group (P < .05). In the HUO group, IL-10 levels were significantly higher (P < .05) on days 4 and 5. Granulocyte CD11a levels on day 2, CD11b levels on days 4 to 6, lymphocyte CD11a on days 5 to 6, CD11b on days 3 to 6, CD49d on days 2 to 6, CD97 on day 6, monocyte CD11a, CD11b, CD18 levels on days 4 to 6, and CD14 levels on days 3 to 5 were significantly higher in the HUO group (P < .05). Our study suggests that ITBVI-guided fluid resuscitation of burned patients suppresses the shift toward anti-inflammatory imbalance and the expression of leukocyte surface markers more than HUO-guided resuscitation.

Effect of N-acetylcysteine treatment on the expression of leukocyte surface markers after burn injury

Oxidative stress and inflammatory processes generate edema in burns. Treatment of consequent hypovolemia is a challenge. The aim of study was to assess if glutathione pro-drug N-acetylcysteine (NAC) can influence inflammation and fluid requirement. We also aimed to compare organ functions scores and vasoactive drug requirement. This prospective randomised study involved 28 patients with burn injury affecting more than 20% of body surface area. Fourteen patients were on standard therapy, whereas for other 14 patients NAC was supplemented. Blood samples were taken on admission and on the next five consecutive mornings. Leukocyte surface marker expressions were determined, multiple organ function scores, use of vasopressor agents and fluid requirements were recorded daily. Expression of CD11a (p < 0.05), CD18 (p < 0.05) and CD97 (p < 0.01) on the granulocytes were significantly lower in the NAC treated group, similarly to lymphocyte CD 49d (p < 0.05) and monocyte CD 49d (p < 0.01) and CD 97 (p < 0.05) expression. No significant difference was found in the fluid requirement between groups but patients the NAC group required less vasopressor and inotropic drugs from day 4. NAC treatment is associated with a less pronounced inflammation reflected in lower CD marker expression and vasopressor requirement.

Use of transesophageal echocardiography in burns:a retrospective review

Transesophageal echocardiography (TEE) is a useful tool in the evaluation and management of critically ill patients. However, it has not been studied in the burn population. The purpose of this review is to describe the safety and utility of TEE in the management of acute burns. This retrospective review included all acute burn inpatients who underwent TEE during a 5-year period at our regional burn center. TEE board-certified anesthesiologists performed all studies. We reviewed the chart of patients who underwent TEE, the indication for TEE, the effect of TEE on clinical management, and complications resulting from TEE. Seventeen burn patients underwent TEE during the review period. The median age was 45.4 years. Fourteen of 17 patients were men (82%). Median TBSA burn was 43.4%. Seven patients (41%) were on vasopressors or inotropic agents at the time of TEE. The main indications for TEE were hypotension and bacteremia. Findings included hypovolemia, mitral valve vegetation, pulmonary hypertension, pericardial effusion, fluid overload, right heart failure, and normal TEE. Therapeutic changes occurred after TEE in two patients; these included initiation of inotropic support and antibiotics. There were no complications identified in association with TEE. TEE is a safe procedure that serves multiple diagnostic purposes. TEE is being used to better understand the fluid status and cardiac physiology of the critically ill burn patient.

The year in burns 2008

For 2008, approximately 1200 original burn research articles were published in scientific journals using the English language. This article reviews those with the most impact on burn treatment according to the Editor of one of the major journals (Burns). As in the previous year's review, articles were divided into the following topic areas: epidemiology, wound characterisation, critical care physiology, inhalation injury, infection, metabolism and nutrition, psychological considerations, pain management, rehabilitation, and burn reconstruction. Each selected article is mentioned briefly with editorial comment.