Comparison of peripheral and central infusions of 7.5% NaCl/6% dextran 70

Although it had been known for several years that central venous injections of hypertonic salt solutions with added dextran could effectively resuscitate animals from hemorrhagic shock, it was not known whether peripheral injections could result in the same beneficial effects. Chronically instrumented, unrestrained, and unanesthetized sheep were subjected to a moderate degree of hemorrhagic shock and then resuscitated with a 2-minute infusion of 7.5% NaCl/6% dextran 70 in a volume of 5 ml/kg body weight. Infusions were made into the cephalic vein, the femoral artery, or, centrally, the superior vena cava. All three routes of injection promptly reestablished arterial pressure and cardiac output. All gave equivalently good restoration of plasma volume. None of the injections damaged the vessels, as determined either by gross inspection or by histologic examination. Thus the solution was safe and effective when given peripherally. It might be useful in the field resuscitation of hypovolemic patients.     

The effects of 7.5% NaCl/6% dextran 70 on coagulation and platelet aggregation in humans.

The combination solution of 7.5% NaCl/6% dextran 70 (HSD) administered IV gives hemodynamic improvement in the treatment of hemorrhagic hypotension. Since earlier dextran solutions were reported to interfere with blood coagulation, the effects of HSD on the prothrombin time (PT), the activated partial thromboplastin time (APTT), platelet aggregation, and platelet concentration were studied. The HSD mixed with human plasma (1:5 and 1:10) slightly prolonged PT, but had no effect on the APTT, compared with saline controls. The HSD also decreased human platelet aggregation at the 1:5 dilution. In separate mixing studies, the hypertonic saline component of HSD was associated with the prolongation of PT and decreased platelet aggregation. The data from these studies indicate that at its proposed therapeutic dose, HSD is expected to have minimal effect on blood coagulation.     

Microcirculatory flow changes after initial resuscitation of hemorrhagic shock with 7.5% hypertonic saline/6% dextran 70.

In rabbits, laser Doppler flow probes were placed in the jejunum and on the renal cortex. Pulsed Doppler probes were implanted on the abdominal aorta and superior mesenteric and femoral arteries for measuring blood flow velocity. Cardiac output was measured by thermal dilution. Either 30% or 40% of the calculated blood volume was withdrawn through a carotid catheter. After 30 or 60 minutes, an initial bolus of either lactated Ringer's (LR, 16 ml/kg) or 7.5% hypertonic saline/6% dextran 70 (HSD; 4 ml/kg) IV was followed by unlimited IV LR (administered as rapidly as possible) to restore systemic arterial blood pressure to the prehemorrhage levels. With HSD, arterial pressure corrected more rapidly (p less than 0.05), and the initial hemodilution was greater (p less than 0.05), but there were no differences by two hours. With HSD, cardiac output (90%-100% vs. 130%-160% of control; p less than 0.05), plasma Na+ (139-140 mM vs. 146-148 mM; p less than 0.05) and plasma osmolarity (292-295 mOsm vs. 308-310 mOsm; p less than 0.05) were all significantly higher than the values with LR, but there was no effect on blood flow velocities through the infrarenal aorta, femoral artery, or superior mesenteric artery. Renal cortical perfusion (56% vs. 97% of control; p less than 0.05) and jejunal mucosal perfusion (83% vs. 162% of control; p less than 0.05) were significantly higher with HSD. HSD had no detectable effect on bacterial translocation at 24 hours. Thus: 1) HSD restores blood flow more rapidly to the gut mucosal and kidney microcirculations than initial resuscitation with LR; 2) the mechanism could be associated with a transient hemodilution and persistent increases in plasma Na and osmolarity, which reduce hemorrhage-induced cell swelling and blood viscosity changes; and 3) laser Doppler analysis could aid in the diagnosis of reperfusion injury after shock.     

7.5% sodium chloride/dextran for resuscitation of trauma patients undergoing helicopter transport.

To evaluate the use of hypertonic saline/dextran solutions in the prehospital resuscitation of severely injured patients, we administered 250 mL of either 7.5% sodium chloride/dextran 70 (HSD) (n = 83) or lactated Ringer's solution (n = 83), followed by conventional isotonic fluids, to 166 trauma patients with systolic blood pressures less than or equal to 100 mm Hg, in a prospective, randomized, double-blinded clinical trial. Patients in the sodium chloride/dextran 70 group required less fluid before hospitalization and arrived in the emergency department with higher systolic blood pressures than patients in the lactated Ringer's solution group. The rate of survival to hospital discharge for the entire cohort was 64% for patients in the sodium chloride/dextran 70 group vs 59% for patients in the lactated Ringer's solution group. The rate of survival to hospital discharge for the patients with severe head injuries was 32% for the sodium chloride/dextran 70 group vs 16% for the lactated Ringer's solution group. Actuarial survival for patients with severe head injuries in the sodium chloride/dextran 70 group compared with patients with severe head injuries in the lactated Ringer's solution group did not quite reach statistical significance. There were no adverse side effects associated with sodium chloride/dextran 70 administration. Administration of small volumes of sodium chloride/dextran 70 before hospitalization increased the blood pressure of severely injured patients more effectively than did lactated Ringer's solution and showed tendencies toward improving survival in the patients with severe head injuries.     

Influence of rate and volume of infusion on the kinetics of 0.9% saline and 7.5% saline/6.0% dextran 70 in sheep

We examined whether volume kinetic variables obtained during infusion of a short bolus of 0.9% saline (NS) or 7.5% saline/6.0% dextran 70 (HSD) predict the dilution-time curve resulting from a 20-min infusion of the same fluid. Each of six conscious, splenectomized sheep (mean body weight, 36 +/- 3 kg), on 4 different days, in a random order, received each of 4 IV boluses: NS at a rate of 1.2 mL. kg(-1). min(-1) over 5 min or 20 min or 4.0 mL/kg of HSD over 2 min or 20 min. One, 2, and 3-volume kinetic models were fitted to the dilution of the arterial hemoglobin concentration and the urinary excretion as sampled during 180 min. The maximum dilution of arterial plasma at the end of the 5-min and 20-min infusions of NS was approximately 10% and 22%, respectively, and after the 2-min and 20-min infusions of HSD, maximum dilution was 24% and 21%, respectively. The median absolute performance error was virtually identical when the mean variable estimates from the 5-min infusion of NS were used to predict the individual dilution-time curves of the 5-min (mean, 0.027 dilution units) and 20-min (mean, 0.027) infusions and when the 2-min infusion of HSD was used to predict the dilution during the individual 2-min (mean, 0.050) and 20-min infusions (mean, 0.047). Computer simulations indicated that the difference at the end of infusion between the volume effects of NS and HSD is larger after longer infusions. We concluded that the volume kinetic variables obtained during a short infusion can be used to predict the outcome of a longer one, even if the longer infusion also delivers a larger volume. IMPLICATIONS: Kinetic analysis of a short infusion of 7.5% saline/6% dextran or 0.9% saline accurately predicts the effects of a longer infusion of the same volume (7.5% saline/6% dextran) or of a larger volume (0.9% saline).     

高张盐溶液与中分子右旋糖酐复苏烧伤休克对犬心肌功能的影响

采用含Ｎａ~＋２５０ｍｍｏｌ／Ｌ的乳酸钠高张盐溶液与６％中分子右旋糖酐（ＨＬＤ）复苏烧伤休克，与乳酸钠林格氏液（ＬＲ）比较，综合评价其复苏效果并探讨其部分机制。结果表明ＨＬＤ组心脏指数（ＣＩ）在伤后４、８、１２、２４ｈ均明显高于ＬＲ组（Ｐ＜０．０５）。ＨＬＤ组心肌收缩功能（ｄｐ／ｄｔｍａｘ），心肌舒张功能（－ｄｐ／ｄｔｍａｘ）在伤后１２、２４ｈ也高于ＬＲ组（Ｐ＜０．０５）。ＨＬＤ组在伤后２４ｈ的心肌ＭＤＡ含量（１．７４±０．２８×１０~（－２）ｍｏｌ／ｇ组织）明显低于ＬＲ组（３．２３±０．５６×１０~（－２）ｍｏｌ／ｇ组织，Ｐ＜０．０５）。而其心肌ＳＯＤ活力（１５７．４９±３２．２３ｕ／ｍｇ组织）明显高于ＬＲ组（４６．８８±１６．２８ｕ／ｍｇ，Ｐ＜０．０１）。提示：与ＬＲ复苏相比，ＨＬＤ复苏烧伤休克能明显改善心肌功能，并可持续到伤后２４ｈ。ＨＬＤ可能通过提高心肌组织ＳＯＤ活力从而降低心肌组织脂质过氧化物含量，减轻脂质过氧化物对细胞膜的损伤，进而起到保护心肌、改善心肌功能的作用。     

高张盐溶液与中分子右旋糖酐复苏烧伤休克对犬心肌功能的影响

采用含 Na~ 250mmol/L 的乳酸钠高张盐溶液与6%中分子右旋糖酐(HLD)复苏烧伤休克,与乳酸钠林格氐液(LR)比较,综合评价其复苏效果并探讨其部分机制。结果表明 HLD 组心脏指数(CI) 在伤后4、8、12、24h 均明显高于 LR 组(P<0.05)。HLD 组心肌收缩功能(dp/dtmax),心肌舒张功能(—dp/dt max)在伤后12、24h 也高于 LR 组(P<0.05)。HLD 组在伤后24h 的心肌 MDA 含量(1.74±0.28×10~(-2)mol/g 组织)明显低于 LR 组(3.23±0.56×10~(-2)mol/g 组织,P<0.05)。而其心肌 SOD 活力(157.49±32·23u/mg 组织)明显高于 LR 组(46.88±16.28u/mg,P<0.01)。提示:与 LR 复苏相比,HLD 复苏烧伤休克能明显改善心肌功能,并可持续到伤后24h。HLD 可能通过提高心肌组织 SOD 活力从而降低心肌组织脂质过氧化物含量,减轻脂质过氧化物对细胞膜的损伤,进而起到保护心肌、改善心肌功能的作用。     

Hypertonic saline resuscitation: efficacy may require early treatment in severely injured patients

BACKGROUND: Activation of polymorphonuclear neutrophils (PMN) is a critical event leading to host tissue injury and organ damage after trauma. Hypertonic saline (HS) resuscitation prevents PMN activation in vitro and in animal models. Here, we studied how clinical parameters and timing requirements influence the efficacy of HS in suppressing PMN activation. MATERIALS AND METHODS: Twenty-six injured patients and 16 healthy volunteers were included as study subjects. To study how clinical parameters affect the efficacy of HS, whole blood samples from patients were collected 24 hours after admission, treated with HS and N-formyl-methionyl-leucyl-phenylalanine (fMLP), and PMN oxidative burst and degranulation were measured using flow cytometry. We studied the effect of timing on the ability of HS to inhibit PMN function by exposing blood of healthy volunteers to plasma samples from trauma patients before or after the addition of fMLP and HS. RESULTS: Age and gender did not significantly influence the effect of HS on PMN function. The suppressive effect of clinically relevant HS concentrations (20 mmol/L) on PMN oxidative burst correlated weakly with Sepsis Severity Score (SSS) and Acute Physiology and Chronic Health Evaluation II (APACHE II) score but not with the Injury Severity Score (ISS) or Multiple Organ Failure score (MOF). There was no correlation between any of these clinical scores and degranulation. HS was significantly less effective in suppressing oxidative burst of PMN from patients with ISS >10, APACHE II >5, MOF >0, or SSS >1 compared with patients with ISS < or =10, APACHE II < or =5, MOF = 0, or SSS < or =1. HS more effectively suppressed PMN activation when PMN were pretreatment with HS, whereas it was less effective on PMN previously primed in vivo or in vitro by adding trauma plasma. HS was ineffective on PMN previously stimulated in vitro with fMLP. CONCLUSIONS: Our data suggest that HS resuscitation may prevent PMN activation most effectively when patients are treated with HS early in the field.     

The resuscitation of the severely injured in the accident and emergency department--a medical audit

An audit of the medical care of the severely injured was conducted in the Accident and Emergency Department of the Royal Victoria Hospital, Belfast. Over a 6-month period the management of all patients admitted with an Injury Severity Score of 16 or over was critically assessed. Errors of management which occurred in 21 of the 36 patients are discussed. They were mainly related to the fact that 78 per cent of the patients arrived outside normal office hours when only inexperienced junior doctors staffed the department. The findings have drawn our attention to the need for both altering staffing arrangements and improving training in our department.     

Nitrogen requirements in severely injured patients

The study was designed to evaluate nitrogen needs in severely injured patients during the first week after trauma. Thirty-nine patients aged from 18 to 65 years with a burn or fractures of more than two long bones were studied. Energy requirements were given parenterally as fat and glucose in isocaloric amounts. The patients were randomized into five groups receiving different amounts of nitrogen from zero to 0.3 g kg body-weight-1 24 h-1. Daily and cumulative nitrogen balance, urinary 3-methylhistidine excretion and nitrogen retention were calculated on days 2-8 after trauma. With no nitrogen, the mean(s.e.m.) daily nitrogen balance after the trauma was -13.8(0.5) gN. The balance improved markedly in groups with a nitrogen intake of up to 0.2 g kg body-weight-1 (P less than 0.001) compared with the no-nitrogen group. The 3-methylhistidine excretion increased because of the trauma in all groups with no statistically significant difference between the groups. Nitrogen retention decreased with increase in nitrogen supply and with time after injury. It is suggested that a nitrogen supply of 0.20 kg bodyweight-1 24 h-1 is optimal for severely injured patients during the first week after trauma.     

Factors influencing the outcome of coma in severely injured patients.

From this analysis we may conclude that the most important factors influencing the outcome of coma due to injury are age, vegetative state, level of coma, decerebration, and hypocapnia. In all cases where a combination of four or more of any of the above-mentioned factors was present the patient died. EEG seems less predictive in the early period, but may give some information for late prognosis.     

Surgery in the resuscitation of critically injured patients

Immediate surgery is essential to resuscitate and save 5% to 10% of those suffering life-threatening trauma. Recently, emergency room surgery has been proposed as the procedure to follow in stabilizing such patients. Over a 3-year period, 41 moribund patients were treated by the trauma service at the Health Sciences Centre in Winnipeg. All were managed in the main operating theatre following a "crash protocol" for immediate surgery. Twenty-three patients arrived in cardiac arrest or with an unrecordable blood pressure; of these, 4 (17%) survived. Eighteen patients had a blood pressure of 70 mm Hg systolic or less and failed to respond to massive O positive blood transfusion; of these, 14 (77%) survived. The mix of mode of injury and injury severity scoring is important to compare results from within and between centres. The author's experience indicates that the use of a high-priority crash protocol for managing moribund patients with life-threatening traumatic injury in the main operating room provides a standard of care equal to or better than that reported for emergency room surgery.     

Coagulation disorders in severely and critically injured patients

Forty-five patients with multiple injuries treated at an intensive care unit were studied prospectively. The patients were divided into two groups: the severely injured (no mortality) and critically injured (56% mortality). Treatment was started within two hours from the accident in all cases. The following coagulation parameters were measured for eight days: euglobulin lysis time (ELT), thromboelastography (TEG), vecalcification time (RECA), partial thromboplastin time (PTT), factor V, factor VIII, Normotest, Thrombotest, thrombin time, fibrinogen and platelets. Severe coagulation disorders were observed in one-third of the patients 12-48 hours after trauma. The abnormalities were more pronounced in patients who had sustained very severe injuries and arrived in a state of shock. The ELT was shortened 0-6 hours after the accident and accelerated coagulation was indicated simultaneously by decreased PTT, RECA, and r-values as well as by elevated Thrombotest and factor VIII values. The factor V and fibrinogen levels were initially lowered. Low platelet values at 2-4 days, prolonged thrombin and r-times, secondary decrease of fibrinogen FV, FVIII, and low Thrombotest values suggested disseminated intravascular coagulation associated with complications, such as fat embolism and "shock lung" syndromes. General bleeding tendency with high mortality was observed in 16% of the patients.     

Altered thyroid function in severely injured patients

BackgroundHemorrhagic shock profoundly affects the neuroendocrine profile of trauma patients, and we hypothesized that massive resuscitation would negatively impact thyroid function.MethodsA prospective, observational study investigating thyroid function in hypotensive trauma patients (systolic blood pressure <90 mm Hg × 2) who survived >48 h was conducted at a Level I center over a 6-mo period. Blood samples for thyroid function were collected at time of presentation to the trauma bay and serially for 48 h. Collected data included demographics, injury data, vital signs, transfusion needs, crystalloid use, and vasopressor requirements. Patients receiving >5 units packed red blood cells (PRBC) within 12 h were compared with those receiving ≤5 units.ResultsPatients who required >5 units of PRBC/12 h had significantly lower total and free T4 levels on initial presentation, and levels remained significantly depressed over the next 48 h when compared with patients who required a less aggressive resuscitative effort. T3 values were markedly suppressed during the initial 48 h post trauma in all patients, but were significantly lower in patients requiring >5 units PRBC. TSH levels remained within the normal range for all time points. Lower trauma admission T4 levels were associated with the need for greater crystalloid resuscitation within the first 24 h.ConclusionMeasurements of thyroid function are significantly altered in severely injured patients on initial presentation, and low T4 levels predict the need for large resuscitation. Further research investigating the profile and impact of thyroid function in trauma patients during resuscitation and recovery is warranted.     

Blood platelets in severely injured burned patients

Unbelievable decrease of blood-platelet in the severely burned patients during the treatment of skingrafting caused two patients to unexpected death. From the records of changes of platelet number, a certain ‘platelet curve’ was made. By observing the curve, our treatments of skingrafting were carried out during the stable period and from then on we had no death cases.     

Algorithms in the early management of severely injured patients

Summary A well-controlled, meticulous process has a far higher probability of resulting in a high quality of medical care than improvisation and unstructured creativity. Algorithms display decision-making treatment processes and problem-solving strategies by giving clearly defined and formalized guidelines. The flow chart for decision-making follows the yes/no dichotomy of binary logic. The systematic ordering of decision points and consequent actions is guided by medical priority and thus regulates the time-frame and sequence of each single step in a logical manner. With the help of clinical algorithms highly complex processes such as the management of the severely injured patient can be translated into a clearly structured, logical pathway. Clinical algorithms represent scientifically recognized treatment rules, indicate a solution for solving problems and help users to organize ideas and recognize connections. They delineate a consistent and valid guideline, while allowing deviations in proven exceptions. The use of algorithms allows a systematic search for errors in the process of quality management. In emergency situations they suggest a structured means of problem solving for the less experienced user. Algorithms are useful instruments in the teaching of medical decision-making.