高渗盐水支气管激发试验预测运动性哮喘的临床价值

目的探讨高渗盐水支气管激发试验预测运动性哮喘（EIA）的临床价值。方法对在本院就诊的36例年轻男性哮喘患者进行支气管激发试验,依次进行高渗盐水激发试验（吸人4．5％高渗盐水）、运动激发试验（间隔24h）及乙酰甲胆碱（MCh）激发试验,并对3者间的相关性进行评价。结果对高渗盐水有高反应性（HS—AHR）的哮喘患者运动后1秒用力呼气量（FEV。）下降的最大值显著高于无HS—AHR患者,运动与高渗盐水所诱发的AHR严重程度具有显著相关性。在预测EIA的价值上,高渗盐水激发试验比MCh激发试验具有更高的特异性（71．4％：42．9％）。当临界值MCh—PC20≤1ms／mL（中度～重度AHR）时,二者对于判断EIA的特异性具有可比性（71．4％：71．4％）,但高渗盐水激发试验对于判断EIA的敏感性低于MCh试验,同时,MCh试验阳性似然比高于HS激发试验,而阴性似然比却更低。结论在预测EIA的价值上,高渗盐水激发试验比MCh激发试验具有更高的特异性,但敏感性较低,而在中度AHR的临界值方面,MCh激发试验能更好地预测EIA。     

Comparison of normal saline, hypertonic saline and hypertonic saline colloid resuscitation fluids in an infant animal model of hypovolemic shock

PurposeIncorrect resuscitation after hypovolemic shock is a major contributor to preventable pediatric death. Several studies have demonstrated that small volumes of hypertonic or hypertonic–hyperoncotic saline can be an effective initial resuscitation solution. However, there are no pediatric studies to recommend their use. The aim of this study is to determine if in an infant animal model of hemorrhagic shock, the use of hypertonic fluids, as opposed to isotonic crystalloids, would improve global hemodynamic and perfusion parameters.MethodsExperimental, randomized animal study including thirty-four 2-to-3-month-old piglets. 30 min after controlled 30 mL kg^?1 bleed, pigs were randomized to receive either normal saline (NS) 30 mL kg^?1 (n = 11), 3% hypertonic saline (HS) 15 mL kg^?1 (n = 12), or 5% albumin plus 3% hypertonic saline (AHS) 15 mL kg^?1 (n = 11).ResultsHigh baseline heart rate (HR) and low mean arterial pressure (MAP), cardiac index (CI), brain tissue oxygenation index (bTOI), and lactate were recorded 30 min after volume withdrawal, with no significant differences between groups. Thirty minutes after volume replacement there were no significant differences between groups for HR (NS, 188 ± 14; HS, 184 ± 14; AHS, 151 ± 14 bpm); MAP (NS, 80 ± 7; HS, 86 ± 7; AHS, 87 ± 7 mmHg); CI (NS, 4.1 ± 0.4; HS, 3.9 ± 0.4; AHS, 5.1 ± 0.4 mL min^?1 m^?2); lactate (NS, 2.8 ± 0.7; HS, 2.3 ± 0.6; AHS, 2.4 ± 0.6 mmol L^?1); bTOI (NS, 43.9 ± 2.2; HS, 40.1 ± 2.5; AHS, 46.1 ± 2.3%).ConclusionsIn this model of hypovolemic shock, hypertonic fluids achieved similar end-points as twice the volume of NS. Animals treated with albumin plus hypertonic saline presented prolonged increase in blood volume parameters and recovery of the oxygen debt.     

Effect of mannitol plus hypertonic saline combination versus hypertonic saline monotherapy on acute kidney injury after traumatic brain injury

PurposeTo compare the effect of mannitol plus hypertonic saline combination (MHS) versus hypertonic saline monotherapy (HS) on renal function in patients with traumatic brain injury (TBI).Materials and methodsThis was a secondary analysis of data from the Resuscitation Outcomes Consortium Hypertonic Saline Trial Shock Study and Traumatic Brain Injury Study. The study cohort included a propensity matched subset of patients with TBI who received MHS or HS. The primary outcome measure was the maximum serum creatinine value during critical illness.ResultsThe cohort consisted of 163 patients in the MHS group and 163 patients in the HS group (n = 326). The maximum serum creatinine value during hospitalization was 82 ± 47 μmol/L (0.86 ± 0.26 mg/dL) in the MHS group and 76 ± 23 μmol/L (0.92 ± 0.53 mg/dL) in the HS group (difference −6 μmol/L, 95% CI −14 to 2 μmol/L, p = .151). The lowest eGFR during hospitalization was 108 ± 25 mL/min in the MHS group and 112 ± 24 mL/min in the HS group (difference −4 mL/min, 95% CI −1 to 9 mLmin, p = .150).ConclusionsThe addition of mannitol to HS did not increase the risk of renal dysfunction compared to HS alone in patients with TBI.     

Effects of hypertonic saline solution on mesenteric microcirculation

We evaluated systemic and microvascular effects of hypertonic NaCl solution on normovolemic and hemorrhaged animals. Forty-three Wistar rats (186 +/- 4 g, mean +/- SEM) were anesthetized with pentobarbital and cannulated for mean arterial pressure (MAP), heart rate (HR), and mean pulse pressure (MPP) monitoring and blood withdrawal. Diameters of 126 arterioles and 88 venules of the exteriorized mesentery were studied by using intravital microscopy. Microvascular blood flow was calculated from diameter and red blood cell velocity measurements. The protocol consisted of 15 min control, 30 min hypotension (MAP = 52.9 +/- 0.9 mmHg, hemorrhaged vol. = 17.1 +/- 0.7 mL/kg) and 60 min post-infusion of either normal (0.9%) or hypertonic saline (7.5%, 4 mL/kg). Normovolemic animals showed no systemic or microvascular effects of hypertonic saline. Hemorrhagic hypotension resulted in HR fall that was not changed after infusions. Hypertonic infusion reversed MPP decrease during hypotension but only partially restored MAP and microvascular blood flow. Venules did not change diameter during protocols. During hypotension, 24% of arterioles displayed vasomotion (38% of the rats) with low- and high-frequency components present in 74% and 87% of arterioles, respectively. Arterioles with vasomotion during hypotension had larger control diameters (28.9 +/- 2.0 microm) and contracted more (30.8 +/- 4.1%) than arterioles without vasomotion (18.7 +/- 1.2 microm and 8.1 +/- 1.5%, respectively). Mean arteriolar diameter did not change after infusions. After hypertonic solution, the number of vessels showing vasomotion increased 80%, frequency of vasomotion was unchanged, and amplitude increased. These findings may help to explain some of the mechanisms underlying resuscitation effects of hypertonic infusions during hemorrhagic hypotension.     

高渗盐水在颅内高压治疗中的应用

目的　以甘露醇作对比 ,探讨用 2 3 4 %高渗盐水治疗颅内高压的效果和副作用。方法　对 15名昏迷的、有侧脑室引流指征的脑出血患者进行共 5 2例次降颅内压治疗。随机决定静脉推注 2 3 4 %高渗盐水 30ml,或静滴 2 0 %甘露醇 2 5 0ml。用药前至用药后 6h内 ,持续监测颅内压 (ICP)、平均动脉压 (MAP)、中心静脉压 (CVP)、脑灌注压 (CPP)、血生化和渗透压。结果　用药后 (2 8± 2 0 )min ,高渗盐水使ICP下降 (2 5± 1 1)kPa (P <0 0 1) ,可持续 3h有效降颅压 ,并可使MAP下降 ;甘露醇在用药后 (4 9± 2 5 )min内 ,使ICP下降 (2 0± 1 3)kPa (P <0 0 1) ,可持续 1h有效降颅压 ,并明显利尿。 6h内两组的CVP、血生化以及渗透压无明显变化 (P >0 0 5 )。结论　 2 3 4 %高渗盐水可有效治疗颅内高压 ,比 2 0 %甘露醇起效更快、更持久 ,效力相当 ,可考虑作为一线降颅内压药物。     

Variable change in renal function by hypertonic saline

AIM: To investigate the effects of hypertonic saline in the neurocritical care population.METHODS: We retrospectively reviewed our hospital’s use of hypertonic saline (HS) since March of 2005, and prospectively since October 2010. Comparisons were made between admission diagnoses, creatinine change (Cr), and HS formulation (3% NaCl, 3% NaCl/sodium acetate mix, and 23.4% NaCl) to patients receiving normal saline or lactated ringers. The patients (n = 1329) of the retrospective portion were identified. The data presented represents the first 230 patients with data.RESULTS: Significant differences in Acute Physiology and Chronic Health Evaluation II scores and Glasgow Coma Scale scores occurred between different saline formulations. No significant correlation of Cl^- or Na⁺ with Cr, nor with saline types, occurred. When dichotomized by diagnosis, significant correlations appear. Traumatic brain injury (TBI) patients demonstrated moderate correlation between Na⁺ and Cr of 0.45. Stroke patients demonstrated weak correlations between Na⁺ and Cr, and Cl^- and Cr (0.19 for both). Patients receiving HS and not diagnosed with intracerebral hemorrhage, stroke, subarachnoid hemorrhage, or TBI demonstrated a weak but significant correlation between Cl^- and Cr at 0.29.CONCLUSION: Cr directly correlates with Na⁺ or Cl^- in stroke, Na⁺ in TBI, and Cl^- in other populations. Prospective comparison of HS and renal function is needed.     

高渗盐水液体复苏对脓毒症患者免疫功能的调节作用

目的 探讨高渗盐水液体复苏对脓毒症患者免疫功能的调节作用.方法 回顾性选择2009年1月到2010年9月在外科重症监护病房( SICU)接受5％高渗盐水液体复苏的24例脓毒症患者,于输注前15 min及输注15 min、6h、12h和24 h抽取全血,用流式细胞仪检测中性粒细胞呼吸爆发能力和表面CD11b、L-选择素,同时留取血浆测定可溶性细胞间黏附分子-1(sICAM-1)、可溶性L-选择素(sL-选择素)、肿瘤坏死因子-α(TN F-α)、白细胞介素(IL-6、IL-1β)水平.结果 设定患者输注高渗盐水前的基础值为100.脓毒症患者输注高渗盐水6h的呼吸爆发能力明显升高[(160.0±19.6)％],与基础值相比有显著差异(P＜0.05),此后逐渐恢复到基础水平.中性粒细胞表面CD11b、L-选择素表达在输注后15 min立刻下调,此作用维持到12h达最低点[(70.4±5.7)％、( 70.6±8.1)％],而后作用逐渐消失,L-选择素在24 h恢复到基础水平.高渗盐水输注短期内,血浆炎症因子TN F-α水平明显下降,此作用维持到12h,并逐渐回升;IL-1β无明显改变;IL-6、sICAM-1逐渐上调,分别在24 h和12h达峰值,并维持在较高水平;sL-选择素于输注15 min即明显高于基础值,并维持至12h,24 h时回落到基础值水平.结论 延迟性高渗盐水复苏对脓毒症患者能发挥显著的免疫调节作用,可抑制中性粒细胞的活化.     

Aminophylline inhibits renal vasoconstriction produced by intrarenal hypertonic saline

An intrarenal infusion of hypertonic saline to sodium-depleted dogs causes an acute reduction in renal blood flow (RBF) which has been postulated to be due to tubuloglomerular feedback (TGF). Adenosine has been suggested as a mediator of TGF, as adenosine receptor blockade with methylxanthines inhibits TGF. In order to test further the hypothesis that the renal response to hypertonic saline is mediated by TGF, the RBF response to intrarenal hypertonic saline infusions have been investigated in sodium-depleted dogs before and after either an infusion of vehicle or an intrarenal infusion of aminophylline. Aminophylline (2.5 mg/min), at a dose which did not change basal RBF or responses to bolus doses of angiotensin II, inhibited the responses to intrarenal bolus doses of adenosine. In control dogs (n = 5), a 10-min intrarenal infusion of hypertonic saline significantly (P less than .05) reduced RBF both before (-27 +/- 4%) and during (-16 +/- 9%) an infusion with aminophylline vehicle. In a second group of animals (n = 5), an intrarenal hypertonic saline infusion reduced RBF before (-33 +/- 8%; P less than .05), but not during an intrarenal aminophylline infusion (2.5 mg/min). We conclude that aminophylline inhibits the renal vascular response to hypertonic saline and that the renal response to hypertonic saline might be mediated by intrarenal adenosine release.     

高渗盐水雾化吸入辅助治疗婴儿毛细支气管炎疗效观察

目的探讨雾化吸入高渗盐水辅助治疗婴儿毛细支气管炎的临床疗效。方法将84例毛细支气管炎患儿分为两组,对照组采用常规治疗,加用生理盐水雾化吸入;治疗组在常规治疗的同时,加用高渗盐水（0.9%氯化钠液2.5 ml和10%浓氯化钠1.5 ml）雾化吸入。结果治疗后两组临床症状、体征均明显改善,治疗组咳嗽、喘息、呼吸急促、三凹征、肺部喘鸣音消失时间及住院天数与对照组比较均明显缩短,总有效率高于对照组,差异均有统计学意义（P〈0.05）。结论在常规治疗婴儿毛细毛细支气管炎同时加用高渗盐水雾化能较快缓解症状,增强疗效,缩短病程,并且安全、有效、简便。     

高渗氯化钠溶液复苏失血性休克的研究进展

<正>创伤患者的死亡绝大多数发生在创伤后1h内,即所谓的"黑色时间"内,致死的主要原因是严重创伤后失血性休克。研究表明,通过创伤后早期的正确处理,可明显减少创伤的死亡率,其中失血性休克的复苏是救治的关键环节。自1980年Velasco等[1]首次报道用小剂量高渗氯     

Superiority of hypertonic saline/dextran over hypertonic saline during the first 30 min of resuscitation following hemorrhagic hypotension in conscious swine.

We compared the effectiveness of intravenously administering hypertonic saline/dextran (HSD; 7.5% NaCl in 6% Dextran-70, n = 6) to hypertonic saline (HS) alone (7.5% NaCl, n = 8) in rectifying detrimental effects of hemorrhage on cardiovascular function. Chronically instrumented conscious swine were hemorrhaged 37.5 ml/kg over 60 min. If untreated, this model is 100% lethal within 60 min. Swine received HSD or HS at 4 ml/kg. Functional variables were measured before and at 5, 15, and 30 min following treatment. HSD produced a significantly greater plasma volume expansion than HS alone (13.6 compared to 9.9 ml/kg). Over 30 min expansion was sustained in pigs receiving HSD but pigs receiving HS regressed. Cardiac index (CI) increased for both treatments, being greater with HSD, 104 ml/kg/min, compared to HS alone, 46 ml/kg/min. Neither group fully sustained these elevated values post-treatment, but remained consistently greater than values after hemorrhage; however, the difference in CI between treatments was maintained. Oxygen delivery showed a trend similar to that of CI. We conclude that resuscitation with HSD is superior to HS in improving cardiovascular function over the first 30 min after hemorrhage.     

高渗盐水联合羟乙基淀粉治疗严重脓毒症的研究

目的 评价7.5%高渗盐水(HS)联合6%羟乙基淀粉(HES)130/0.4对严重脓毒症患者早期液体复苏的效果.方法 采用前瞻性随机对照研究.选取江汉大学附属医院重症监护病房(ICU)135例严重脓毒症患者,入ICU时随机分成3组,每组45例.HS+HES组输注7.5%HS后输注6%HES 130/0.4 500 ml,再输注平衡液HES组输注6%HES 130/0.4后输注平衡液;平衡液组(RL组)仅输注平衡液.比较3组患者入ICU后6 h、24 h平均动脉压(MAP)、氧合指数(PaO2/FiO2)、动脉血乳酸、乳酸清除率、急性生理学与慢性健康状况评分系统Ⅱ(APACHE Ⅱ)评分、输液量、尿量以及多器官功能障碍综合征(MODS)发生率和住院病死率.结果 入ICU后6 h,HS+HES组MAP[mm Hg(1 mm Hg=0.133 kPa):68.7±3.0]、PaO2/FiO2(mm Hg:262.2±17.4)、乳酸清除率[(21±4)%]较HES组[MAP:63.8±3.5,PaO2/FiO2:252.0±21.2,乳酸清除率:(11±2)%]和RL组[MAP:62.6±3.6,PaO2/FiO2:248.4±17.0,乳酸清除率:(9±1)%]显著增高(均P＜0.01),动脉血乳酸(mmol/L:3.5±0.7)较HES组(4.1±0.7)和RL组(4.0±0.7)显著下降(均P＜0.01);APACHE Ⅱ评分(分:13.2±1.9)与HES组(14.0±1.6)无明显差异,但显著低于RL组(15.2±1.7,P＜0.01).入ICU后24 h,HS+HES组PaO2/FiO2(mm Hg:303.3±17.3)显著高于HES组(282.9±21.1)和RL组(268.9±15.2,均P＜0.01),但3组间MAP、动脉血乳酸、乳酸清除率和APACHE Ⅱ评分均无差异.人ICU后6 h、24 h,HS+HES组输液量(ml,6 h:1 877.8±215.2,24 h:5 475.6±208.8)显著低于HES组(6 h:2 505.6±276.2,24 h:6 383.3±287.4)和RL组(6 h:3 496.7±325.5,24 h:7 439.6±229.6);尿量(ml,6 h:294.2±36.9,24 h:2 793.8±37.1)显著高于HES组(6 h:248.9±25.3,24 h:2 248.9±25.3)和RL组(6 h:178.9±14.8,24 h:2 000.4±147.0,均P＜0.01).HS+HES组MODS发生率(6.7%)远低于RL组(28.9%,P＜0.05),与HES组(17.8%)无差异(P＞0.05);3组间病死率无显著差异(HS+HES组2.2%,HES组4.4%,RL组8.9%,均P＞0.05).结论 7.5%HS联合6%HES 130/0.4能提高严重脓毒症患者早期液体复苏的效果,降低MODS发生率.

Abstract：

Objective To evaluate the effect of 7. 5% hypertonic saline(HS)and 6% hydroxyethyl starch (HES)130/0.4 on early fluid resuscitation for severe sepsis. Methods Prospective randomized control trial was carried out in intensive care unit(ICU)of the Affiliated Hospital of Jianghan University. One hundred and thirty-five patients with severe sepsis were randomly divided into three groups, each group consisted of 45 patients. Patients in HS+HES group received lactated Ringer solution following 4 ml/kg of 7. 5%HS and 6%HES 130/0. 4 500 ml, those in HES group received lactated Ringer solution following 6%HES 130/0.4500 ml, and those in the lactated Ringer group(RL group)received lactated Ringer solution only. Mean arterial pressure(MAP), oxygenation index(PaO2/FiO2), arterial lactate(Lac), lactate clearance rate,acute physiology and chronic health evaluation Ⅱ(APACHE Ⅱ)score, fluid infusion volume, urine output as well as incidence of multiple organ dysfunction syndrome(MODS), and mortality were compared among three groups at 6 hours and 24 hours after ICU admission. Results At 6 hours after ICU admission, MAP [mm Hg(1 mm Hg=0. 133 kPa): 68. 7±3. 0], PaO2/FiO2(mm Hg: 262.2±17.4), lactate clearance rate [(21±4)%]in HS+HES group were significantly higher than those in HES group[MAP: 63. 8±3.5,PaO2/FiO2: 252.0 ± 21.2, lactate clearance rate:(11± 2)%]and RL group[MAP: 62.6 ± 3. 6, PaO2/FiO2 :248. 4±17.0, lactate clearance rate:(9± 1)%, all P＜0. 01]. Arterial Lac in HS+HES group(mmol/L:3. 5±0. 7)was significantly lower than that in HES group(4. 1±0. 7)and RL group(4. 0±0. 7, both P＜0. 01). There was no significant difference in APACHE Ⅱ score between HS+HES group(13. 2±1.9)and HES group(14.0±1.6), and the APACHE Ⅱ score in HS+HES group was significantly lower than that in RL group(15. 2 ± 1.7, P＜ 0. 01). At 24 hours after ICU admission, PaO2/FiO2(mm Hg: 303.3 ± 17.3)was significantly higher in HS+HES group than that in HES group(282.9 ± 21.1)and RL group(268. 9 ±15.2,both P＜ 0.01). There was no significant difference in MAP, arterial Lac, lactate clearance rate and APACHE Ⅱ score among three groups. At 6 hours and 24 hours after ICU admission, fluid infusion volume in HS+HES group(ml, 6 hours: 1 877. 8±215. 2, 24 hours: 5 475.6±208.8)was markedly less than that in HES group(6 hours: 2 505.6±276.2, 24 hours: 6 383. 3±287.4)and RL group(6 hours: 3 496. 7±325.5, 24 hours: 7 439.6±229.6), yet urine output in HS+HES group(ml, 6 hours: 294.2±36.9,24 hours: 2 793.8 ±37.1)was significantly higher than that in HES group(6 hours: 248.9 ± 25. 3,24 hours: 2 248. 9±25. 3)and RL group(6 hours: 178. 9±14.8, 24 hours: 2 000. 4±147.0, all P＜0. 01).The incidence of MODS in HS+HES group(6.7%)was statistically lower than that in RL group(28. 9%,P＜0. 05), while no obvious difference was found between HS+HES group and HES group(17.8%, P＞0. 05). There was no significant difference in mortality among three groups(HS+HES group: 2.2%, HES group: 4.4%, RL group: 8.9%, all P＞0. 05). Conclusion 7.5%HS and 6%HES 130/0. 4 could improve the effect of early fluid resuscitation on severe sepsis, and it could lower the incidence of MODS.     

Resuscitation from hemorrhagic shock: experimental model comparing normal saline,dextran, and hypertonic saline solutions

OBJECTIVE: To compare the effectiveness of normal saline, dextran, hypertonic, and hypertonic-hyperoncotic solutions in hemorrhagic shock. DESIGN: Laboratory investigation. SETTING: University hospital, Emergency Surgery and Intensive Care staff. SUBJECTS: Thirty-two large white female pigs. INTERVENTIONS: Routine care included: anesthesia and sedation (ketamine 10 mg/kg, droperidol 0.25 mg/kg, diazepam 0.7 mg/kg, fentanyl 0.006 mg/kg, 2% enflurane, 20% nitrous oxide, pancuronium bromide 0.13 mg/kg); volume-controlled ventilation (Paco(2) 35-40 torr; 4.7-5.4 kPa); cannulation of right carotid artery and pulmonary artery. Three flow probes (subdiaphragmatic aorta, superior mesenteric artery, right renal artery) and regional venous catheters (superior mesenteric vein, right renal vein) were positioned. Animals were bled to 45 mm Hg for 1 hr and resuscitated with four different fluids and blood to normal aortic blood flow and hemoglobin. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure and blood flow through abdominal aorta ([OV0312](aor)), mesenteric artery ([OV0312](mes)), and renal artery ([OV0312](ren)) were continuously monitored. Cardiac output, systemic and regional oxygen delivery ([U1E0A]o(2), [U1E0A]o(2mes), [U1E0A]o(2ren)), and consumption ([OV0312]o(2), [OV0312]o(2mes), [OV0312]o(2ren)) were recorded every 30 mins. Baseline [OV0312](aor) was restored with different amounts of fluids in the four groups: normal saline (91.35 +/- 22.18 mL/kg); dextran (16.24 +/- 4.42 mL/kg); hypertonic (13.70 +/- 1.44 mL/kg); and hypertonic-hyperoncotic (9.11 +/- 1.20 mL/kg). The amount of sodium load was less using dextran and hypertonic-hyperoncotic and sodium levels were only transiently increased after hypertonic infusion. Mean arterial pressure and cardiac output were normalized in all groups. Animals resuscitated with normal saline and dextran showed increased pulmonary artery pressures. [U1E0A]o(2) was significantly higher after hypertonic-hyperoncotic infusion, because of reduced hemodilution. Hypertonic and hypertonic-hyperoncotic normalized [OV0312](mes), [U1E0A]o(2mes), [OV0312]o(2mes), [OV0312](ren), and [U1E0A]o(2ren), whereas normal saline and dextran did not achieve this result. At the end of the experiment, hypertonic-hyperoncotic maintained mean arterial pressure, cardiac output, and [U1E0A]o(2) until the end of observation in contrast to normal saline, dextran, and hypertonic. CONCLUSIONS: Resuscitation with a small volume of hypertonic-hyperoncotic solution allows systemic and splanchnic hemodynamic and oxygen transport recovery, without an increase in pulmonary artery pressure. It only transiently increased sodium concentration.     

The effect of hypertonic saline dextran on whole blood coagulation

Hypertonic saline dextran (RescueFlow) is being promoted for resuscitation from hypovolaemia following injury. We studied the in vitro effect on coagulation of serial dilutions of blood with this fluid. There was a mild procoagulant effect up to a dilution of 11% and an anticoagulant effect above this level, which rapidly increased so that coagulation was grossly deranged at a 15% dilution. Although the clinical significance of these findings is not yet known, it may suggest that for hypertonic saline dextran there is little to separate the top of the therapeutic window from the threshold of potentially serious adverse effects.     

Effect of sputum induction by hypertonic saline on specimen quality

Microbiologic work-up of expectorated material is routinely used to search for the etiology of pulmonary infections, but sputum is often contaminated by saliva. Inhalation of hypertonic saline induces bronchial secretions and theoretically may improve specimen quality. We compared in a laboratory-blinded, randomized study the quality of sputum obtained either with induction by saline or without induction in patients with respiratory tract infection and a history of productive cough. The quality of sputum was considered good if the polymorphonuclear neutrophils (PMNs)/squamous epithelial cells (SECs) ratio was > or = 2 or the Q (quality) score was > or = +1 on Gram stain. Forty-nine and 50 patients were able to expectorate in the induced and spontaneous sputum groups, respectively. PMNs/SECs ratio was > or = 2 in 65% and 74% of the patients in the induced and spontaneous sputum groups (p = 0.47); for the Q score, a value > or = +1 was found in 55% and 66% of the patients of each group (p = 0.37). In conclusion, sputum induction by hypertonic saline inhalation does not improve specimen quality as judged by the PMNs/SECs ratio on Gram stain.     

Iatrogenic compartment syndrome from hypertonic saline injection in bier block

A case study of an iatrogenic forearm compartment syndrome is presented. The patient underwent intravenous regional anesthesia (Bier's block) for an attempted closed reduction of a Bennett's fracture. Hypertonic saline (23.4%) was inadvertently used as a lidocaine diluent for the Bier's block, and after tourniquet release, the patient developed signs and symptoms of an acute compartment syndrome. An emergent fasciotomy was required. A review the theoretical pathogenesis of compartment syndrome resulting from intravenous injection of hypertonic saline is presented. While vein sclerosis from IV hypertonic saline may play a role in the development of a compartment syndrome, we speculate that the major factor was an increase in the extracellular tissue fluid volume resulting from osmotic equilibrium after the tourniquet was released. The need for meticulous attention to details when performing this technique is emphasized.