小儿大面积烧伤后急救复苏十倍法补液公式的创建与应用

目的探讨研究小儿大面积烧伤后急救复苏十倍法补液公式的科学性和可行性。方法采用回顾性观察性研究方法。收集2014年1月1日—12月31日国内72家三级甲等医院烧伤科收治的符合入选标准的433例大面积烧伤患儿(男250例、女183例, 年龄3个月龄～14岁)的烧伤总面积[30%～100%体表总面积(TBSA)]和体重(6～50 kg)。将6～50 kg中的每一体重(编程步长为0.5 kg)与烧伤总面积为30%～100%TBSA中的每一面积(编程步长为1%TBSA)配对后的6 319对模拟数据, 代入3个公认小儿补液公式——国内常用的小儿烧伤补液公式(以下简称国内补液公式)、加尔维斯顿公式和辛辛那提公式与2个小儿急救补液公式——世界卫生组织烧伤技术工作小组(TWGB)提出的大面积烧伤患者急救简化复苏方案(以下简称TWGB公式)和该文作者提出的小儿十倍法补液公式:补液速度(mL/h)=体重(kg)×10(mL·kg-1·h-1), 计算伤后8 h内补液速度(以下简称补液速度)。以3个公认小儿补液公式的计算结果±20%的范围为合理补液速度, 计算并比较采用2个小儿急救补液公式计算的补液速度的准确...     

改善早期补液方式减轻烧伤后早期内脏损害

20世纪50年代初Evans创立了补充胶体与电解质溶液的Evans公式，奠立了烧伤补液公式的基本原则。如：(1)烧伤体液丧失量与烧伤面积、体重成正比。(2)烧伤丧失的液体类似血浆，应补充血浆与电解质，同时要补充必需水分。(3)烧伤后体液立即丧失，6-8h至高峰，故伤后第1个8h应补充24h补液量的一半。(4)主要依靠尿量进行监护。随后有许多补液公式问世。但自应用有创监护以来，虽然用传统公式复苏能使患度过休克期，     

口服补液复苏对严重烧伤家兔心肌力学指标的改善作用

目的 了解口服补液复苏对严重烧伤家兔心脏功能的保护作用. 方法 150只家兔随机分为正常对照组(6只)、烧伤组(42只)、立即补液组(42只)、延迟补液组(30只)和延迟快速补液组(30只).正常对照组不致伤不补液.其余4组家兔均造成40%TBSAⅢ度烧伤,烧伤组不补液,余下3组伤后用灌胃的方式进行口服补液复苏.经家兔颈动脉左心室内置管,测量正常对照组及4组致伤家兔伤后2、6、8、12、24、36、48 h的平均动脉压(MAP)、左心室收缩压(LVSP)、左心室舒张末期压(LVEDP)以及左心室压力最大上升/下降速率(LV±dp/dt max),另检测休克期尿量. 结果烧伤组家兔LVSP、LV±dp/dt max较正常对照组显著下降.立即补液组和延迟快速补液组上述指标在伤后24 h内高于烧伤组,其中立即补液组LV+dp/dt max在伤后8 h达峰值[(892±116)kPa/s,1 kPa=7.5 mm Hg],LV-dp/dt max在伤后6 h达峰值[(724±149)kPa/s];伤后8 h,延迟快速补液组LV±dp/dt max均达峰值.延迟补液组伤后各时相点LVSP、LV±dp/dt max与烧伤组接近.各组家兔MAP、伤后第1个24 h尿量的比较情况大致与以上指标相似.烧伤组与其余4组比较,各时相点LVEDP差异无统计学意义(P>0.05). 结论严重烧伤家兔伤后24 h内给予有效的口服补液,可改善心肌力学指标;延迟复苏的家兔按照延迟复苏补液公式预估补液量,才能进行有效复苏.     

延迟快速复苏对烧伤休克循环影响的临床研究

目的探讨在烧伤延迟复苏情况下,如何迅速纠正休克.方法通过对20例烧伤面积大于40%TBSA、因延迟复苏导致休克的患者,进行延迟快速复苏.观察休克期液体出入量、动咏压(BP)、肺动脉压(PAP)、肺动脉楔状压(PAWP)、中心静脉压(CVP)、心输出量(CO)、肺血管阻力(PVR)、外周血管阻力(SVR)、氧供应(DO2)、氧消耗(VO2)、氧摄取率(O2ext)、乳酸(LA)及碱缺失(BD)等血流动力学和氧代谢指标的变化.结果快速补液后2h内输入液体占“第一个24h公式计算量”的(38.8±6.1)%,如果加上院外补液量则占“第一个24h公式计算量”的(48.3±5.0)%.第一个24h实际补入量占“第一个24h公式计算量”的(131.4±14.3)%;第二个24h实际补入量占“第二个24h公式计算量”的(103.2±7.2)%.快速补液后,尿量大幅增加,CO显著升高,DO2增强,SVR、LA、BD大幅下降,PVR虽大幅升高,但PAWP、PAP和CVP并未超过正常.结论在严密血流动力学监护下,烧伤后延迟复苏初期加快补液速度是可行且有益的,烧伤休克的延迟复苏需要显著增加补液量.指导休克延迟快速复苏应以监护心输出量及PAP、PAWP、CVP等血流动力学指标为主,辅以血中LA、BD水平及尿量变化等临床指标的监测.     

早期口服补液对犬50%总体表面积烧伤休克期血流动力学和组织灌流的影响

目的 研究早期口服补液对犬50%总体表面积(TBSA)烧伤休克期血流动力学和组织灌流的影响.方法 成年雄性Beagle犬18只,先期无菌手术行颈总动脉、颈外静脉、胃、空肠及膀胱置管,24 h后用凝固汽油燃烧法造成其颈、背和胸、腹部约50%TBSA Ⅲ.烧伤.随机分为不补液(NR)、口服补液(OR)和静脉补液(IR)三组,每组6只.伤后第1个24 h NR组无治疗,OR和IR组于伤后30 min开始按Parkland公式分别从胃管和静脉输注葡萄糖.电解质溶液,伤后24 h起各组犬均实施静脉补液.测定犬伤前(0 h)和伤后2、4、8、24、48和72 h非麻醉状态下的平均动脉压(MAP)、全身血管阻力(SVR)、心输出量(CO)、左室内压最大变化速率(dp/dtmax)、尿量以及胃黏膜CO2分压(PgCO2)和小肠黏膜血流量(IMBF),并记录伤后72 h死亡率.结果 与伤前相比,各组犬MAP、CO、dp/dtmax,、IMBF和尿量在伤后2 h均大幅降低(P<0.01),而SVR和PgCO2显著升高.两补液组上述指标伤后8 h开始恢复,72 h IR组除IMBF外均恢复至伤前水平,但OR组CO、SVR及胃肠组织灌流指标仍差于伤前水平(P<0.01).NR组上述指标持续恶化,伤后24 h内无尿并全部死亡.OR组血液动力学和内脏组织灌流指标显著优于NR组,但差于IR组.伤后72 h死亡率NR组为6/6、OR组3/6,而IR组为0/6.结论 50%TBSA烧伤后早期口服葡萄糖-电解质溶液复苏效果虽差于静脉补液,但相比不补液,能显著改善血流动力学指标和内脏组织灌流,减少早期死亡,有潜力成为战争或灾害时静脉液体复苏的替代方法.     

重度烧伤患者早期液体复苏与血钠变化观察

目的 了解重度烧伤患者早期电解质与胶体混合液体复苏量、电解质与胶体比值及血钠的改变. 方法 选择2004年3月-2009年3月笔者单位收治的烧伤总面积大于或等于70%,且Ⅲ度面积大于或等于50%TBSA的67例行液体复苏患者.回顾性总结患者伤后24、48、72 h电解质、胶体和水分的输入量及尿量,同时记录患者不同时间段血钠变化与补液情况.数据用SPSS 13.0软件行统计学分析. 结果 67例患者中,9例早期出现低钠血症、5例出现高钠血症、53例血钠正常.患者伤后72 h内尿量均在70 mL/h以上.患者实际补充的电解质和胶体总量(mL)=烧伤总面积(%TBSA)×体质量(kg)×K,上述公式中的K值在伤后第1个24 h约为1.7,电解质与胶体比值约为1.4;伤后第2个24 h的K值为1.3,电解质与胶体比值为1.6;伤后第3个24 h的K值为0.9,比值为2.0. 结论 重度烧伤患者早期实际液体复苏量略大于传统公式计算量(K值为1.5).早期液体复苏过程中电解质量以及电解质与胶体比值会影响患者血钠水平.     

肠内输入高渗盐糖溶液对严重烧伤犬肠黏膜屏障及脏器功能的影响

目的 了解烧伤犬休克期经肠道补充高渗盐糖溶液(HEGS)进行复苏后,肠道屏障及脏器功能的变化. 方法 将24只35%TBSAⅢ度烧伤犬按随机数字表法分为不补液(NF)组、静脉等渗补液(Ⅱ)组、肠内等渗补液(EI)组和肠内高渗补液(EH)组,每组6只.2个等渗补液组于伤后30 min分别通过静脉或肠道给予含50 g/L葡萄糖的生理盐水,24 h补液量为4 mL·kg~(-1)·%TBSA~(-1)(前8 h匀速输入总量的一半,后16 h匀速输入另一半);EH组经肠道输入HEGS(含18 g/L氯化钠、50 g/L葡萄糖),伤后24 h内补液量为2 mL·kg~(-1)·%TBSA~(-1),补液方式同前.测定各组犬肝肾功能指标[血清ALT、心肌型肌酸激酶同工酶(CK-MB)活性及肌酐、尿素氮水平]、血清二胺氧化酶(DAO)活性以及伤后24 h肠黏膜Na~+-K~+·ATP酶活性. 结果 各组犬血清ALT活性相近.3个补液组血肌酐、尿素氮水平普遍低于NF组;伤后2 h CK-MB活性均明显升高,EH组伤后2～8 h低于NF、Ⅱ组.Ⅱ、EI、EH组血清DAO活性于伤后4 h或6 h起逐渐降低,分别为(3.9±0.6)～(3.6±0.5)U/L、(4.8±0.4)～(2.8±0.8)U/L和(6.4±1.8)～(3.5±0.8)U/L,均显著低于NF组(12.5±0.4)～(9.7±1.1)U/L(EH组与NF组比较,伤后4、6、8、24 h t值分别为10.25、12.44、17.99、16.21,P值均小于0.05).伤后24 h各组肠黏膜Na~+-K~+-ATP酶活性从高到低依次为Ⅱ组、EH组、EI组、NF组(前3组与NF组比较,t值分别为10.09、8.32、4.96,F值为26.79,P值均小于0.05). 结论 HEGS对烧伤休克犬的肠黏膜屏障无明显不良影响.与NF比较,HEGS能显著改善伤犬心、肝、肾功能;减少1/2补液量,能达到与肠内或静脉输入等渗盐糖溶液相似的复苏效果.     

卡巴胆碱对犬烧伤休克早期口服补液效果的影响

目的 观察卡巴胆碱对50%总体表面积(TBSA)Ⅲ度烧伤早期口服补液效果的影响.方法 Beagle犬17条,先期行颈动、静脉、胃及膀胱置管,24 h后用凝固汽油燃烧造成50%TBSAⅢ度烧伤.随机分为不补液组、胃内补液组和胃内补液+卡巴胆碱组.伤后第1个24 h不补液组无治疗,其余2组于伤后30 min开始经胃内输注葡萄糖-电解质液或葡萄糖-电解质液复合卡巴胆碱(20 μg/kg).第1个24 h补液量为4 ml·kg~(-1)·%TBSA~(-1);伤后24 h起各组动物均实施静脉补液,至72 h处死动物.测定两胃内补液组伤后8 h内胃排空率,各组72 h内平均动脉压(MAP)、心输出量(CO)、尿量、血浆肿瘤坏死因子(TNF)-α含量以及伤后72 h脏器组织一氧化氮合酶(NOS)活性变化.结果 伤后3组MAP、CO、尿量及胃排空率均显著降低,血浆TNF-α含量显著增高.两胃内补液组MAP和CO高于不补液组;胃内补液+CAR组CO和胃排空率伤后4 h起显著高于胃内补液组(P<0.01),伤后24 h尿量也显著多于胃内补液组,伤后2、4和8 h血浆TNF-α含量以及伤后72h心、肝和空肠组织NOS活性显著低于胃内补液组(P<0.01或P<0.05).结论 卡巴胆碱能提高50%TBSA烧伤早期口服补液的复苏效果,其作用机制可能与促进胃排空和减轻炎症反应有关.     

口服补液对烧伤休克犬肺组织含水量和血管通透性的影响

目的 了解口服补液对烧伤休克犬肺组织含水量和血管通透性的影响.方法 雄性Beagle犬18只,行颈动、静脉置管后24 h造成50%TBSAⅢ度烧伤.伤后随机分为不补液组、口服补液组和静脉补液组,每组6只.伤后第1个24 h不补液组不作任何治疗,口服补液组和静脉补液组分别经胃管或静脉输注葡萄糖-电解质溶液;伤后24 h起3组犬均给予静脉补液.统计各组犬伤后72 h内的死亡率.测定3组犬伤前、伤后30 min和4、8、24、48、72 h非麻孵状态下的平均动脉压(MAP)、呼吸频率(RR)、PaO2、血管外肺水指数(ELWI)和肺血管通透性指数(PVPI),于伤后72 h或犬濒死前测定肺组织含水率.结果 不补液组6只犬均在伤后9～22 h死亡,口服补液组中3只犬伤后25～47 h死亡,静脉补液组犬无一死亡.不补液组伤后8 h RR为(44.0±5.0)次/min、ELWI(10.3±0.6)mL/kg、PVPI 6.6±0.6,比伤前大幅增加;PaO2和MAP均明显低于伤前(P<0.05).口服补液组伤后8 h RR为(33.0±4.0)次/min、ELWI(8.9±0.3)mL/kg、PVPI 5.7±0.4,显著低于不补液组(P<0.05),但高于静脉补液组[(26.0±3.0)次/min、(8.2±0.3)mL/kg、4.2±0.4,P<0.05];口服补液组PaO2和MAP均高于不补液组(P<0.05).两补液组肺组织含水率相近(P>0.05),均低于不补液组(P<0.05).结论 早期口服补液对烧伤犬肺的保护作用虽不如静脉补液,但与不补液相比能显著改善休克期肺血管通透性,减轻肺水肿,减少肺脏并发症.     

烧伤患者创面水分丢失量实用计算法

目的探讨更为简便、实用的烧伤创面水分丢失量计算方法。方法85例成年烧伤患者,烧伤面积均在50%TBSA以上,测算休克期后(伤后3d)患者24hWWL(ml·%TBSA-1·kg-1)=[入量(ml/24h)-尿量(ml/24h)-500ml]÷实际创面面积(%TBSA)÷体重(kg),同时与其他公式(Davies、S.M.S.P、Lamke)及手掌测量法进行比较。结果烧伤患者休克期后每日WWL为(0.9±0.1)ml·%TBSA-1·kg-1,几种计算公式结果相近。体重60kg左右患者的WWL计算方法可以进一步简化为手掌法。结论利用推荐公式及手掌法进行WWL计算,方法简单便于记忆,适合在临床应用。     

Fluid resuscitation for major burn patients with the TMMU protocol

Background

Fluid resuscitation is one of the critical treatments for the major burn patient in the early phases after injury. We evaluated the practice of fluid resuscitation for severely burned patients with the Third Military Medical University (TMMU) protocol, which is most widely used in many regions of China.

Methods

Patients with major burns (>30% total body surface area (TBSA)) presenting to Southwest Hospital, Third Military Medical University, between January 2005 and October 2007, were included in this study. Fluid resuscitation was initiated by the TMMU protocol.

Results

A total of 71 patients were (46 adults and 25 children) included in this study. All patients survived the first 48 h after injury smoothly and none developed abdominal compartment syndrome or other recognised complications associated with fluid resuscitation. The average quantity of fluid infused was 3.3–61.33% more than that calculated based on the TMMU protocol in both adult and paediatric groups. The average urine output during the first 24 h after injury was about 1.2 ml per kg body weight per hour in the two groups, but reached 1.2 ml and 1.7 ml during the second 24 h in adult and pediatric groups, respectively.

Conclusion

This study indicates that the TMMU protocol for fluid resuscitation is a feasible option for burn patients. Individualised resuscitation – guided by the physiological response to fluid administration – is still important as in other protocols.     

犬烧伤休克延迟复苏的实验研究

目的探讨应用林格液进行烧伤休克延迟复苏的效果.方法12只犬随机分为对照组(S组,6只)和治疗组(LR组,6只).LR组采用35%TBSAⅢ度烧伤模型,伤后6h以乳酸林格液进行复苏,并以尿量为1.0ml@kg-1@h-1及心输出量为伤前值的70%～80%来调整输液速度及输入量,观察其在伤后第一个24h复苏中的容量负荷、平均动脉压(MAP)、左心室收缩压(LVSP)、左室内压最大上升/下降速率(±dp/dtmax)、心脏排血指数(CI)、氧供给(DO2)及氧消耗(VO2)等的变化.结果乳酸林格液在烧伤休克延迟复苏后第一个24h的复苏中,每1%烧伤面积的输液量为(887±1.02)ml/kg,比采用Parkland公式复苏多1.2倍,其中在复苏后4h内的输液量为(3.63±0.99)ml/kg,为总入量的41%;MAP、LVSP、±dp/dtmax、CI、DO2及VO2等指标在复苏后2h即达到或接近对照组水平.结论乳酸林格液在烧伤休克延迟复苏中,比早期复苏需要更多的液体量才能满足需求,而血流动力学、心肌功能及氧动力学等在复苏后2h即有明显改善.     

Current status of burn resuscitation

Rapid assessment and management of airway and breathing problems are required in the patient with severe burns complicated by significant facial burns and inhalation injury. A policy that results in intubation of all patients at potential risk for airway compromise can be both foolish and dangerous. At the same time, it is recognized that intubation of patients who are likely to develop unstable airways is necessary if transport times to burn centers are long and if i.v. resuscitation is initiated during transport. The ideal burn resuscitation formula does not exist. Whichever formula is used, patients must be monitored closely and the fluid resuscitation individualized according to their responses. Patients with delay in resuscitation, associated trauma, inhalation injury, or alcohol abuse may require fluid resuscitations greater than those predicted. The goal is to maintain urine outputs in the range of 0.5 to 1 mL/kg/hr for adults and 1 to 1.5 mL/kg/hr in children. In patients with fluid requirements greater than 150% of that predicted by formula, the addition of colloid at 12 hours can reduce total fluid requirements and burn edema. Early placement of pulmonary artery catheters can be useful in patients with known myocardial dysfunction, age greater than 65 years, severe inhalation injury, or fluid requirements greater than 150% of that predicted by formula.     

Hypertonic lactated saline resuscitation reduces the risk of abdominal compartment syndrome in severely burned patients

BACKGROUND: Secondary abdominal compartment syndrome is a lethal complication after resuscitation from burn shock. Hypertonic lactated saline (HLS) infusion reduces early fluid requirements in burn shock, but the effects of HLS on intraabdominal pressure have not been clarified. METHODS: Patients admitted to our burn unit between 2002 and 2004 with burns > or =40% of the total body surface area without severe inhalation injury were entered into a fluid resuscitation protocol using HLS (n = 14) or lactated Ringer's solution (n = 22). Urine output was monitored hourly with a goal of 0.5 to 1.0 mL/kg per hour. Hemodynamic parameters, blood gas analysis, intrabladder pressure as an indicator of intraabdominal pressure (IAP), and the peak inspiratory pressure were recorded. Pulmonary compliance and the abdominal perfusion pressure were also calculated. RESULTS: In the HLS group, the amount of intravenous fluid volume needed to maintain adequate urine output was less at 3.1 +/- 0.9 versus 5.2 +/- 1.2 mL/24 h per kg per percentage of total body surface area, and the peak IAP and peak inspiratory pressure at 24 hours after injury were significantly lower than those in the lactated Ringer's group. Two of 14 patients (14%) in the HLS group and 11 of 22 patients (50%) developed IAH within 20.8 +/- 7.2 hours after injury. CONCLUSION: In patients with severe burn injury, a large intravenous fluid volume decreases abdominal perfusion during the resuscitative period because of increased IAP. Our data suggest that HLS resuscitation could reduce the risk of secondary abdominal compartment syndrome with lower fluid load in burn shock patients.     

Hypertonic saline dextran resuscitation fails to improve cardiac function in neonatal and senescent burned guinea pigs.

Our previous studies suggested that the greater diminution in burn-induced cardiac contractile function which occurs in young and elderly subjects compared with adult subjects is related to differences in intracellular calcium availability to the myofilaments. We recently showed that improved cardiac function after hypertonic saline dextran (HSD) resuscitation from burn injury in adults was related to enhanced intracellular calcium content. In the study presented here, 126 hearts isolated from neonatal, adult, and senescent guinea pigs were used to evaluate age-related differences in cardiac contractile response to HSD resuscitation from burn injury. Scald burn was induced in 30 adult, 18 neonatal, and 30 senescent guinea pigs; within each age group, half of the burned animals were resuscitated with lactated Ringer's (Parkland formula, 4 mL/kg/% burn for 24 hours); half received an initial bolus of HSD (4 mL/kg, IV) plus lactated Ringer's (1 mL/kg/% burn for 24 hours). An additional 16 animals from each age group served as sham burn controls.(ABSTRACT TRUNCATED AT 250 WORDS)     

A practical formula for fluid resuscitation in acute paediatric burns in a low resource setting: A pilot study

BackgroundAppropriate fluid resuscitation of acute burn injury is critical and there are recognized challenges with fluid resuscitation, including those with relevance to low resource settings. We developed a practical protocol that guides burn resuscitation and sought to evaluate the safety of our modified resuscitation formula through a small pilot study that particularly addresses the problems we have experienced in a low resource setting.MethodsChildren with burns more than 15% total body surface area admitted within 24 h of injury to Edendale Hospital between 1 June 2021 and 31 August 2021 were included. The resuscitation formula used was 2 mls of Ringers Lactate per bodyweight in kilograms per% total body surface area (TBSA) given over 24 h and adjusted according to urine output. Data analysed included age, weight, mechanism, TBSA, hours post burn at presentation to hospital, total fluid given in the first 24 h of admission, total urine output in the first 24 h of admission, number of fluid adjustments made during the first 24 h and complications related to fluid resuscitation.ResultsTen children were included. The median age was 3 (IQR 2–5) years old, with a mean weight of 14.9 (SD 5.07) kilograms, a median TBSA of 17.4 (IQR 16–26)%, presenting at a median of 12 (6.5–18) hours post burn injury. Mechanism of burn was scald in all cases, with 9 being hot water and hot food in one. In the first 24 h a mean of 2.05 (SD 0.58) mls/kg of fluid was received with a mean urine output of 1.66 (SD 0.57) mls/kg/hr.ConclusionThe results of this pilot study to evaluate the safety of our protocol seem reasonable. It is limited by the lack of larger injuries as well as adult patients and a larger prospective study is pertinent.     

Predicting increased fluid requirements during the resuscitation of thermally injured patients

BACKGROUND: We determined whether factors present soon after burn predict which patients will receive more than 4 mL/kg/% burn during the first 24 hours, and whether total fluid intake during the first 24 hours (VOL) contributes to in-hospital mortality (MORT). METHODS: We reviewed the records of patients admitted during 1987-97. The modified Brooke resuscitation formula was used. One hundred four patients met inclusion criteria: total body surface area burned (TBSA) > or = 20%; admission directly from the field; weight > 30 kg; no electric injury, mechanical trauma, or blood transfusions; and survival > or = 24 hours postburn. Eighty-nine records were complete. RESULTS: Mean TBSA was 43%, mean full-thickness burn size was 21%, mean age was 41 years, mean VOL was 4.9 mL/kg/% burn, and mean lactated Ringer's volume was 4.4 mL/kg/% burn; 53% had inhalation injury. MORT was 25.8%. Mean urine output was 0.77 mL/kg/h. By linear regression, VOL was associated with weight (negatively) and full-thickness burn size (r2 = 0.151). By logistic regression, receipt of over 4 mL/kg/% burn was predicted at admission by weight (negatively) and TBSA; by 24 hours postburn, mechanical ventilation replaced TBSA. With respect to MORT, logistic regression of admission factors yielded a model incorporating TBSA and an age function; by 24 hours postburn, the worst base deficit was added. CONCLUSION: Burn size and weight (negatively) were associated with greater VOL. However, a close linear relationship between burn size and VOL was not observed. Mechanical ventilation supplanted TBSA by 24 hours as a predictor of high VOL. Worst base deficit, TBSA, and an age function, but not VOL, were predictors of MORT.     

Reduction of resuscitation fluid volumes in severely burned patients using ascorbic acid administration: a randomized, prospective study

HYPOTHESIS: High-dose ascorbic acid (vitamin C) therapy (66 mg/kg per hour) attenuates postburn lipid peroxidation, resuscitation fluid volume requirements, and edema generation in severely burned patients. STUDY DESIGN AND SETTING: A prospective, randomized study at a university trauma and critical care center in Japan. SUBJECTS AND METHODS: Thirty-seven patients with burns over more than 30% of their total body surface area (TBSA) hospitalized within 2 hours after injury were randomly divided into ascorbic acid and control groups. Fluid resuscitation was performed using Ringer lactate solution to maintain stable hemodynamic measurements and adequate urine output (0.5-1.0 ml/kg per hour). In the ascorbic acid group (n = 19; mean burn size, 63% +/- 26% TBSA; mean burn index, 57 +/- 26; inhalation injury, 15/ 19), ascorbic acid was infused during the initial 24-hour study period. In the control group (n = 18; mean burn size, 53% +/- 17% TBSA; mean burn index, 47 +/- 13; inhalation injury, 12/18), no ascorbic acid was infused. We compared hemodynamic and respiratory measurements, lipid peroxidation, and fluid balance for 96 hours after injury. Two-way analysis of variance and Tukey test were used to analyze the data. RESULTS: Heart rate, mean arterial pressure, central venous pressure, arterial pH, base deficit, and urine outputs were equivalent in both groups. The 24-hour total fluid infusion volumes in the control and ascorbic acid groups were 5.5 +/- 3.1 and 3.0 +/- 1.7 mL/kg per percentage of burn area, respectively (P<.01). In the first 24 hours, the ascorbic acid group gained 9.2% +/- 8.2% of pretreatment weight; controls, 17.8% +/- 6.9%. Burned tissue water content was 6.1 +/- 1.8 vs 2.6 +/- 1.7 mL/g of dry weight in the control and ascorbic acid groups, respectively (P<.01). Fluid retention in the second 24 hours was also significantly reduced in the ascorbic acid group. In the control group, the ratio of PaO2 to fraction of inspired oxygen at 18, 24, 36, 48, and 72 hours after injury was less than that of the ascorbic acid group (P<.01). The length of mechanical ventilation in the control and ascorbic acid groups was 21.3 +/- 15.6 and 12.1 +/- 8.8 days, respectively (P<.05). Serum malondialdehyde levels were lower in the ascorbic acid group at 18, 24, and 36 hours after injury (P<.05). CONCLUSIONS: Adjuvant administration of high-dose ascorbic acid during the first 24 hours after thermal injury significantly reduces resuscitation fluid volume requirements, body weight gain, and wound edema. A reduction in the severity of respiratory dysfunction was also apparent in these patients.     

PNU282987对烧伤休克犬复苏时脂质过氧化损伤和组织含水率的影响

目的：研究α7烟碱型乙酰胆碱受体（α7nAChR）激动剂PNU282987对致死性烧伤休克犬脂质过氧化损伤和组织含水率的影响.方法：成年雄性Beagle犬12只,按完全随机数字表法分为烧伤补液组和烧伤PNU282987组,每组6只.采用凝固汽油燃烧法造成50%总体表面积Ⅲ度烧伤.于伤后0.5 h分别通过颈静脉补液,烧伤补液组给予林格液,烧伤PNU282987组给予等量含有PNU282987 （0.38 mg/kg）的林格液.补液量和速率均根据Parkland公式确定.于伤前和伤后2、4、8、12和24 h颈静脉取血,测定丙二醛（MDA）含量和超氧化物歧化酶（SOD）活性,并于伤后24 h处死动物,留取心、肝、脾、肺、肾和回肠组织,测定组织含水率.结果：两组犬伤后SOD水平显著降低;伤后4 h起烧伤PNU282987组SOD水平显著高于烧伤补液组（P＜0.05）,而单纯烧伤组SOD水平持续降低.两组犬伤后MDA水平均上升,伤后4h起烧伤PNU282987组血浆MDA水平均显著低于烧伤补液组（P＜0.05）.烧伤PNU282987组脏器含水率显著低于烧伤补液组[心：（68.6±1.1）% vs.（78.3±1.8）%;肝：（70.0±1.4）% vs.（ 79.8±0.7）%;脾：（67.2±1.2）% vs.（78.8±0.8）%;肺：（74.3±0.5）% vs.（ 80.2±1.6）%;肾：（71.2±0.8）% vs.（ 80.1±0.9）%;回肠：（68.9±1.1）% vs.（ 78.7±0.8）%],差异均有统计学意义（P＜0.05）.结论：PNU282987能抑制烧伤休克犬复苏时引起的脏器氧自由基生成,减轻组织水肿,具有潜在临床应用价值.     

Effectiveness of Parkland formula in the estimation of resuscitation fluid volume in adult thermal burns

Purpose: Acute burn resuscitation in initial 24 h remains a challenge to plastic surgeons. Though various formulae for fluid infusion are available but consensus is still lacking, resulting in under resuscitation or over resuscitation. Parkland formula is widely used but recently its adequacy is questioned in studies. This study was conducted to see how closely the actual volume of fluid given in our center matches with that of calculated volume by Parkland formula. Methods: All patients admitted with more than 20% flame burn injury and within 8 h of incident were included in this study. Crystalloid solution for infusion was calculated as per Parkland formula; however, it was titrated according to the urine output. Data on fluid infusion were collected from patient''s inpatient records and analyzed. Results: The study included a total of 90 patients, about 86.7% (n ¼ 78) of the patients received fluid less than the calculated Parkland formula. Rate of fluid administered over 24 h in our study was 3.149 mL/kg/h. Mean hourly urine output was found to be 0.993 mL/kg/h. The mean difference between fluid administered and fluid calculated by Parkland formula was 3431.825 mL which was significant (p < 0.001). Conclusion: The study showed a significant difference in the fluid infused based on urine output and the fluid calculated by Parkland formula. This probably is because fluid infused based on end point of resuscitation was more physiological than fluid calculated based on formulae.