Performance Evaluation of Geometrically Different Pediatric Arterial Cannulae in a Pediatric Cardiopulmonary Bypass Model

ABSTRACT Objective: To define a reference chart comparing pressure drop vs. flow generated by a set of arterial cannulae currently utilized in cardiopulmonary bypass conditions in pediatric surgery. Methods: Cannulae from two manufacturers were selected considering their design and outer and inner diameters. Cannula performance was evaluated in terms of pressure drop vs. flow during simulated cardiopulmonary bypass conditions. The experimental circuits consisted of a Jostra HL-20 roller pump, a Quadrox-i pediatric oxygenator (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set. The circuit was primed with lactated Ringer's solution only (first condition) and with human packed red blood cells added (second condition) to achieve a hematocrit of 30%. Cannula sizes 8 to 16 Fr were inserted into the cardiopulmonary bypass circuit with a "Y" connector. The flow was adjusted in 100 ml/min increments within typical flow ranges for each cannula. Pre-cannula and post-cannula pressures were measured to calculate the pressure drop. Results: Utilizing a pressure drop limit of 100 mmHg, our results suggest a recommended flow limit of 500, 900, 1400, 2600, and 3100 mL/min for Braile arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, respectively. For Medtronic DLP arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, the recommended flow limit is 600, 1100, 1700, 2700, and 3300 mL/min, respectively. Conclusion: This study reinforces discrepancies in pressure drop between cannulae of the same diameter supplied by different manufacturers and the importance of independent translational research to evaluate components' performance.

Avaliação de soluções eletrolíticas e vias da administração sobre o teor de umidade das fezes de equinos desidratados experimentalmente / Evaluation of electrolyte solutions and administration routes on the moisture content of feces of experimentally dehydrated horses

A ocorrência de processos fisiopatológicos que cursam com desidratação da ingesta no trato gastrointestinal dos equinos é comum na rotina clínica. Fatores como diminuição da motilidade intestinal e sobrecarga intraluminal de conteúdo desidratado podem levar a compactação em segmentos como estômago, ceco e cólons. Este estudo objetivou realizar a comparação entre soluções eletrolíticas enterais hipotônica (SeHIPO) e isotônica (SeISO) e a solução Ringer com lactato de sódio (RL IV) sobre o teor de umidade das fezes de equinos submetidos a um período de desidratação experimental (PD). Foram utilizados seis equinos adultos, todas fêmeas com idades entre 10 e 15 anos, média de 440 kg de peso corpóreo. O PD constou de 36 horas de jejum hídrico e alimentar associadas a duas administrações intravenosas de furosemida, sendo a primeira imediatamente no início (T-36) e a segunda 12 horas após o início do PD. Os tratamentos utilizados foram: SeHIPO e SeISO, ambas administradas por via nasogástrica em fluxo contínuo (HETfc), e RL IV administrada pela via intravenosa. Todos os tratamentos foram administrados a uma taxa de infusão contínua de 15mL kg-1 h-1 durante 8 horas consecutivas. O delineamento experimental utilizado foi o crossover6x3, onde cada animal foi submetido, em sistema de rodízio, aos três tratamentos em momentos distintos. As soluções eletrolíticas enterais demonstraram maior eficácia na recomposição do teor de umidade das fezes quando comparadas à terapia RL IV. A hidratação enteral com soluções isotônicas e hipotônicas administrada em fluxo contínuo são eficazes em restaurar o teor de umidade das fezes, podendo ofertar uma opção econômica, segura e eficiente na reidratação de pacientes e nas afecções que cursam como obstruções intraluminais simples.

The occurrence of pathophysiological processes that curse with digesta dryness in the gastrointestinal tract of horses is common in clinical routine, factors such as decreased intestinal motility and intraluminal overload of dry content can lead to compaction in segments such as cecum and colon. This study aimed to compare a hypotonic enteral solution (SeHIPO), an isotonic enteral solution (SeISO) and a Ringer with sodium lactate solution (RL IV) over the moisture content of equine feces submitted to an experimental dehydration protocol. Six adult horses were used, all females aged between 10 and 15 years, average body weight of 440 kg. The PD consisted of a 36 hours period of water and food fasting associated with two intravenous administrations of furosemide, the first immediately at the beginning (T-36) and the second 12 hours after the beginning of the PD. The treatments used were: SeHIPO (hypotonic enteral solution administered via nasogastric), SeISO (enteral isotonic solution administered via nasogastric) and RL IV (Ringer's solution with sodium lactate administered intravenously), all treatments were administered by continuous infusion at a rate of 15mL kg-1 h-1 for 8 consecutive hours. The experimental design used was the 6x3 crossover, where each animal is submitted, in a rotation system, to the three treatments at different times. Enteral fluid therapy with isotonic and hypotonic solutions administered in continuous flow are effective in restoring the moisture content of feces, and may offer an economical, safe, and efficient option for rehydrating patients and in conditions that progress as simple intraluminal obstructions.

New Ringer's lactate gel formulation on nasal comfort and humidification / Nova formulação de Ringer lactato gel no conforto e umidificação nasal

Abstract Introduction: The use of saline irrigation for nasal washes is a well established procedure in the treatment of sinonasal inflammation and infection. In addition to saline solutions, Ringer's lactate is also an efficient option for nasal washes and humidification. Objective: To assess the comfort, humidification and tolerance regarding stinging sensation, provided by sodium chloride nasal gel at the concentrations of 4.5 mg/g and 6.0 mg/g through questionnaires answered by the patients. Methods: A total of 60 patients, 56 females, aged between 22 and 66 years old (mean age of 47) and 4 males, aged between 36 and 66 years (mean age of 49), were included in the study for a period of 17 days (±2 days) treatment. The patients were monitored by a general practitioner throughout the study period. They were instructed to apply each product in both nostrils twice a day during a 7-day period (±2 days). The patients were evaluated prior to the use of the first product at visit 0 (V0), after 7 days of treatment (±2 days) at visit 1 (V1), after 3 days of product discontinuation at visit 2 (V2) and after 7 days (±2 days) of treatment with the second product, in visit 3 (V3). Results: A significant difference (5% significance) was observed regarding comfort and stinging sensation between the two different concentrations; comfort was higher and stinging was lower with the 6.0 mg/g concentration gel. No difference in humidification was observed between the two treatments. Conclusion: Ringer's lactate at the concentration of 6.0 mg/g was superior to that at 4.5 mg/g for parameters comfort and stinging sensation. No statistical difference was observed between the two products regarding nasal humidification.

Resumo Introdução: O uso de soluções salinas para lavagem nasal está consagrado no tratamento de quadros inflamatórios e infecciosos nasossinusais. Além das soluções salinas, o ringer lactato é uma importante opção tanto para lavagem quanto para a hidratação nasal. Objetivo: Avaliar a tolerabilidade (ardência e conforto) e umidificação do produto gel nasal cloreto de sódio 4,5 mg/g em relação ao ringer lactato 6,0 mg/g, por meio de questionários respondidos pelos pacientes. Método: Foram incluídos 60 pacientes, 56 mulheres (22-66 anos; média: 47 anos) e quatro homens (36-66 anos; média: 49 anos) foram incluídos no estudo de 17 dias (± 2 dias) de tratamento. Os pacientes foram supervisionados por um clínico geral durante todo o período do estudo. Os pacientes usaram os produtos com uma borrifada em cada narina duas vezes ao dia, durante sete dias (± 2 dias). As formulações foram avaliadas antes do uso do primeiro produto na visita 0 (V0), após sete dias (± 2 dias) de tratamento na visita 1 (V1), após três dias de interrupção do primeiro tratamento na visita 2 (V2) e após sete dias (± 2 dias) de uso do segundo produto na visita 3 (V3). Resultados: Foi observada diferença significante para o conforto das vias nasais, (significância de 5%), na comparação entre os tratamentos nos atributos de conforto e ardência. O conforto das vias nasais foi superior e a ardência inferior para o gel nasal ringer lactato 6,0 mg/g em comparação ao gel cloreto de sódio 4,5 mg/g. Não foi observada diferença significante para a umidificação entre os tratamentos. Conclusão: O gel ringer lactato 6,0 mg/g foi superior ao produto gel cloreto de sódio 4,5 mg/g nos quesitos conforto e ardência. Não foi observada diferença estatisticamente significante entre os tratamentos em relação à umidificação das vias nasais.

Comparison of endothelial cell changes by specular microscopy between Ringer's and Ringer's lactate during phacoemulsification / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To compare the difference between using Ringer's and Ringer's lactate(RL)solutions as irrigating solutions during phacoemulsification and investigate their effect on corneal endothelium.<p>METHODS: This was a prospective interventional double blinded clinical study that included 100 eyes of 100 patients aged between 50 to 65 years suffering from a visually significant age-related cataract and scheduled for routine uncomplicated phacoemulsification. The included eyes were randomly divided into two equal groups(each group included 50 eyes). Group 1 received Ringer's solution and group 2 received Ringer's lactate as an irrigating solution.<p>RESULTS: The first group with Ringer's solution had a mean age of 57.5±8 years and the second group with RL solution had a mean age of 58.6±9 years. After 3mo, endothelial cell density decreased in group 1 by a mean of 8.5%, and in group 2 by a mean of 3.6%(<i>P</i>=0.013). Additionally, central corneal thickness increased in group 1 by a mean of 6.9% and in group 2 by a mean of 1.5%(<i>P</i>=0.006). By correlating the percentage of change in pachymetry and specular microscopic parameters with volume of irrigation solution used, there was no significant correlation.<p>CONCLUSION: The use of Ringer's lactate as an irrigating solution is associated with less endothelial cell loss postoperatively in comparison to Ringer's solution and also associated with decreased postoperative edema.

Density and morphology of corneal endothelial cell after phacoemulsification using Ringer lactate versus balanced salt solution as irrigating solutions / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the difference in corneal endothelial cell density and morphology after phacoemulsification using Ringer lactate ( RL ) and balanced salt solution ( BSS) irrigating solutions.?METHODS: The prospective randomized controlled trial study was conducted between February 2017 and April 2017 in Dr. YAP Eye Hospital, Yogyakarta, Indonesia. There were a total of 52 subjects ( 52 eyes ) who were senile cataract patients further grouped into two, 26 patients undergoing the phacoemulsification procedure using RL irrigating solution and the other 26 patients with BSS irrigating solution, both conducted by one operator. On the 1, 7, and 28d post operative, an evaluation was done to measure the density and corneal endothelial cell morphology, as well as the variable of inflammation in the two groups.? RESULTS: Fifty - two eyes had undergone phacoemulsification with posterior intraocular lens implantation. Both groups were evaluated for the endothelial cell reduction and corneal endothelial cell morphology change, along with post - operative inflammation. On the 28d post-operative, endothelial cell reduction in the BSS group ( 173. 96 cell/mm2 , 8. 12％) was lower than the RL group (253.20 cell/mm2, 10.25％), percentage of corneal endothelial cell variation coefficient increase in the BSS group ( 2. 92％, 8. 36％) was lower compared to the RL group (3. 42％, 9. 96％), decrease of hexagonal cells of corneal endothelium cells presentation percentage in the BSS group (4. 30％, 8. 17％) was lower compared to the RL group (4. 84％, 8. 97％), and the percentage increase of central corneal thickness in the BSS group (4. 69 μm, 0. 89％) was almost equal to the RL group (4. 53 μm, 0. 90％). All of the results regarding difference in density and corneal cell endothelium morphology between the two groups did not reveal any statistically significant difference (P>0. 05). Inflammatory variable in the two groups were even.? CONCLUSION: BSS and RL were equal in their capability of maintaining endothelial cell loss and endothelial cell morphologic change in senile cataract patients after phacoemulsification.

Comparative study of preloading with ringer lactate v/s 6% hexa starch solutions to prevent hypotension following spinal anaesthesia in elective surgery.

Background: Hemodynamic variations are commonly encountered following subarchnoid block and can attribute to significant mortality and morbidity. To counteract the hypotension, fluid adminstration before spinal anaesthesia is recommended (preloading). Crystalloids and colloids are recommended as preloading fluids but both have their own merits and demerits. Objective: This comparative study was done to compare the effectiveness of ringer lactate versus 6% hydroxyl ethyl starch for preventing spinal anesthesia induced hypotension. Material and Methods: In this prospective study, we compare the effectiveness of ringer lactate versus 6% hydroxy ethyl starch at 10ml/kg over a period of 20 minutes before spinal anaesthesia in preventing hypotension. After administration of spinal anaestheisa mean arterial pressure were recorded at 1, 5, 10, 15, 30, 45, 60, 90 minutes and 3 hours after spinal anaesthesia. Number of patient, recieving injection Mephentermine sulphate for persistent hypotension was also recorded. Results: We found that hydroxy ethyl starch is more effective than ringer lactate solution as a preloading fluid in prevention of hypotension following spinal anaesthesia. Conclusion: Hydroxy ethyl starch is superior to ringer lactate in preventing hypotension in patients undergoing elective lower abdominal surgeries under spinal anaesthesia but the incidence of hypotension is not completely eliminated.

The influence of hydroxyethyl starch on exogenous coagulation and active protein C in patients with septic shock / 中华危重病急救医学

Objective To investigate the influence of hydroxyethyl starch solution on exogenous coagulation and active protein C (APC) in the patients with septic shock.Methods A single-center prospective study was conducted.Eighty-four consecutive patients with septic shock admitted to intensive care unit (ICU) of Peking University People's Hospital from November 2009 to October 2014 were enrolled.The patients were randomized into two study groups by random digits table:Ringer lactate solution group (RL group,n =40) and hydroxyethyl starch group (HES group,n =44),and Ringer lactate solution or hydroxyethl starch 130/0.4 was used for resuscitation respectively.Peripheral blood was collected at four time points:before resuscitation,6,12,and 24 hours after resuscitation.The prothrombin time (PT),tissue factor (TF),tissue factor pathway inhibitor (TFPI) and APC were determined,and the length of ICU stay and the mortality were recorded.Results There were no significant differences in PT,TF,TFPI,and APC before and after resuscitation in RL group.No change in PT was found after resuscitation in HES group,and no significant difference was found as compared with RL group.TF after resuscitation in HES group was decreased gradually,and the level at the 24 hours after resuscitation was significantly lower than that before resuscitation (U/L:15.80±7.32 vs.31.40±2.75,P ＜ 0.05); but there was no significant difference at all time points when compared with that of RL group (all P ＞ 0.05).TFPI at 12 hours and 24 hours after resuscitation in HES group was increased when compared with before resuscitation (μg/L:1.32±0.22,1.14±0.09 vs.0.63±0.54).TFPI in HES group was significantly higher than that in RL group (μg/L:0.84 ± 0.69,0.95 ± 0.30),but there was no significant differences between two groups (both P ＞ 0.05).APC after resuscitation in HES group was decreased gradually,which was significantly lower than that in RL group at 6,12,24 hours after resuscitation (mg/L:3.38±3.00 vs.5.98±4.12,3.31 ± 1.94 vs.5.33 ± 3.71,3.42 ± 2.64 vs.7.53 ± 4.67,P ＜ 0.05 or P ＜ 0.01).The length of ICU stay in HES group was significantly shorter than that in RL group (days:12.50 ± 8.83 vs.17.10± 16.60,t =9.037,P ＜ 0.001),but there was no significant difference in mortality between HES group and RL group [40.9％ (18/44) vs.60.0％ (24/40),x 2=2.339,P =0.126].Conclusions Both RL and hydroxyethyl starch fluid resuscitation did not affect the PT of the patients.The use of hydroxyethyl starch probably inhibits excessive activation of the exogenous coagulation and hyper-coagulation in the early stage of sepsis,and inhibits activation of protein C as well.

Efeito da ressuscitação volêmica precoce na resposta inflamatória e no estresse oxidativo cardiovascular do choque séptico experimental / SvO2 guided resuscitation for experimental septic shock: effects of fluid infusion and dobutamine on hemodynamics, inflammatory response and cardiovascular oxidative stress

Os mecanismos fisiopatológicos associados aos efeitos benéficos da reanimação guiada pela saturação venosa mista de oxigênio (SvO2) durante a sepse não são claros. Nosso objetivo foi avaliar os efeitos de um algoritmo de reanimação guiado pela SvO2 incluindo fluidos, noradrenalina e dobutamina na hemodinâmica, resposta inflamatória e estresse oxidativo cardiovascular durante um modelo experimental que se assemelha clinicamente ao choque séptico. Dezoito porcos anestesiados e cateterizados (35-45 kg) foram submetidos à peritonite por inoculação fecal (0,75 g/Kg). Depois de permanecerem hipotensos, antibióticos foram administrados e os animais foram randomizados em dois grupos: controle (n=9), com suporte hemodinâmico visando pressão venosa central de 8-12 mmHg, débito urinário de 0,5 ml/kg por hora, e pressão arterial média acima de 65 mmHg; e grupo SvO2 (n=9), com os objetivos acima referidos, além de SvO2 acima de 65%. As intervenções duraram 12 hs e incluíram Ringer Lactato e norepinefrina (ambos os grupos) e dobutamina (grupo SvO2). A resposta inflamatória foi avaliada pela concentração plasmática de citocinas, expressão de CD14 de neutrófilos, geração de espécies reativas de oxigênio e apoptose. O estresse oxidativo foi avaliado pelas concentrações de nitratos no miocárdio e no plasma, a atividade miocárdica e vascular de NAD(P)H oxidase, conteúdo de glutationa do miocárdio e expressão de nitrotirosina. A reanimação guiada por SvO2 foi associada com melhor índice sistólico, oferta de oxigênio e diurese. A sepse induziu em ambos os grupos um aumento significativo na concentração de IL-6, nas concentrações de nitrato de plasma e diminuição persistente na expressão de CD14 em neutrófilos. A apoptose e a geração de espécies reativas de oxigênio por neutrófilos não foram diferentes entre os grupos. As estratégias de tratamento não alteraram significativamente os parâmetros de estresse oxidativo. Assim, uma abordagem destinada a otimizar a SvO2...

The pathogenetic mechanisms associated to the beneficial effects of mixed venous oxygen saturation (SvO2)-guided resuscitation during sepsis are unclear. Our purpose was to evaluate the effects of an algorithm of SvO2-driven resuscitation including fluids, norepinephrine and dobutamine on hemodynamics, inflammatory response and cardiovascular oxidative stress during a clinically resembling experimental model of septic shock. Eighteen anesthetized and catheterized pigs (35-45 Kg) were submitted to peritonitis by fecal inoculation (0.75 g/Kg). After hypotension, antibiotics were administered, and the animals were randomized to two groups: control (n=9), with hemodynamic support aiming central venous pressure 8 to 12 mmHg, urinary output 0.5 ml/Kg per hour, and mean arterial pressure greater than 65 mmHg; and group SvO2 (n =9), with the goals above, plus SvO2 greater than 65%. The interventions lasted 12 h, and lactated Ringer's and norepinephrine (both groups) and dobutamine (SvO2 group) were administered. Inflammatory response was evaluated by plasma concentration of cytokines, neutrophil CD14 expression, oxidant generation, and apoptosis. Oxidative stress was evaluated by plasma and myocardial nitrate concentrations, myocardial and vascular NAD(P)H oxidase activity, myocardial glutathione content, and nitrotyrosine expression. Mixed venous oxygen saturation-driven resuscitation was associated with improved systolic index, oxygen delivery, and diuresis. Sepsis induced in both groups a significant increase on IL-6 concentrations and plasma nitrate concentrations and persistent decrease in neutrophil CD14 expression. Apoptosis rate and neutrophil oxidant generation were not different between groups. Treatment strategies did not significantly modify oxidative stress parameters. Thus, an approach aiming SvO2 during sepsis improves hemoynamics, without any significant effect on inflammatory response and oxidative stress. The beneficial effects...

Evaluation of hemostatic changes using n thromboelastography after crystalloid or colloid fluid administration during major orthopedic surgery

The effects of Ringer lactate, 6% hydroxyethyl starch (HES) (130/0.4) or 4% succinylated gelatin solutions on perioperative coagulability were measured by thromboelastography (TEG). Seventy-five patients (ASA I-III) who were to undergo major orthopedic procedures performed under epidural anesthesia were included in the study. Patients were randomly divided into three groups of 25 each for the administration of maintenance fluids: group RL (Ringer lactate), group HES (6% HES 130/0.4), and group JEL (4% gelofusine solution). Blood samples were obtained during the perioperative period before epidural anesthesia (t1, baseline), at the end of the surgery (t2), and 24 h after the operation (t3). TEG data, reaction time (R), coagulation time (K), angle value (α), and maximum amplitude (MA) were recorded. TEG parameters changed from normal values in all patients. In group RL, R and K times decreased compared to perioperative values while the α angle and MA increased (P < 0.05). In group HES, R and K times increased, however, the α angle and MA decreased (P < 0.05). In group JEL, R time increased (P < 0.05), but K time, α angle and MA did not change significantly. In the present study, RL, 6% HES (130/0.4) and 4% JEL solutions caused changes in the coagulation system of all patients as measured by TEG, but these changes remained within normal limits.

NGAL como marcador precoce de lesão renal em ratos submetidos à isquemia renal sob anestesia geral balanceada / NGAL as an early marker of renal injury in rats submitted to renal ischemia under general balanced anesthesia

A lesão renal aguda (LRA) caracterizada como redução abrupta da função renal tem incidência variável, dependendo dos critérios utilizados para sua definição. Atualmente, o mais empregado para avaliação de função renal é a dosagem de creatinina plasmática, porém, por sofrer interferência de vários fatores faz com que a mesma não seja o marcador ideal. Um novo biomarcador da função renal, a lipocalina associada à gelatinase dos neutrófilos (NGAL), tem sido estudado como um dos mais precoces e sensíveis marcadores de lesão de rins após isquemia/reperfusão ou lesão nefrotóxica, sendo facilmente identificada no sangue e na urina. A classificação RIFLE para LRA com a validação da NGAL é uma nova perspectiva para o diagnóstico precoce da LRA e instituição de medidas preventivas e protetoras em situações de risco. O objetivo dessa pesquisa foi avaliar a LRA por meio da dosagem plasmática da NGAL em ratos submetidos à isquemia renal sob anestesia geral balanceada e hidratados com Ringer lactato ou com hidroxietilamido e correlacionar a dosagem da NGAL plasmática com a lesão histológica renal. Em trinta ratos Wistar machos (>350g) distribuídos aleatoriamente em três grupos de dez animais, induzidos com isoflurano a 4%, foi realizada intubação orotraqueal e colocados sob ventilação mecânica. Foram cateterizadas a artéria carótida esquerda e a veia jugular direita para monitorização e coletas sanguíneas. ETCO2, PAMI, T foram continuamente monitorizados (Datex, AS3)...

Acute renal injury (ARI), characterized by abrupt renal function decline, has variable incidence, depending on the criteria used for its definition. Presently, the criterion most often used for kidney function evaluation is plasma creatinine dosing; however, because it suffers interference, it is not an ideal marker. A new renal function biomarker, neutrophil gelatinase-associated lipocalin (NGAL) has been studied as one of the earliest and most sensitive kidney injury marker following ischemia/reperfusion or nephrotoxic injury, and it is easily identified in blood and urine. The RIFLE classification for ARI with NGAL validation is a new perspective for early ARI diagnosis and institution of preventive and protective measures in risk situations. This study aimed at evaluating ARI by means of NGAL plasma dosing in rats submitted to renal ischemia under general balanced anesthesia and hydrated with ringer lactate or hydroxyethylamide and at correlating plasma NGAL dosing with histological renal injury. Thirty male Wistar rats (>350g) were used. They were randomly distributed into three groups with ten animals each and induced by 4% isoflurane. Orotracheal intubation was performed and the animals were placed under mechanical ventilation. The left carotid artery and the right jugular vein were catheterized for monitorization and blood collection. ETCO2, PAMI, T were continuously monitorized (Datex, AS3)...

Post-operative endophthalmitis: Antibiogram & genetic relatedness between Pseudomonas aeruginosa isolates from patients & phacoemulsifiers.

Background & objectives: Though not frequently but there are reports showing phacoemulsifiers as a potent source of infection in post-operative cases of endophthalmitis. This study was carried out to find antibiogram and genetic relatedness between Pseudomonas aeruginosa isolates from a post-cataract surgery endophthalmitis outbreak (3 patients) and internal tubings of 5 phacoemulsifiers. Methods: In vitro antimicrobial sensitivity patterns of the 8 bacterial isolates were observed. Genetic analysis of the bacterial isolates was done using random amplification of polymorphic DNA (RAPD) assay and PCR ribotyping. The resulting DNA band patterns were examined visually and by computer assisted analysis using unweighted pair group method. Results: The three P. aeruginosa patient isolates were found to be different from the five phacoemulsifier isolates in sensitivity towards 3 antibiotics and by genetic analysis (33 and 44% homology by RAPD assay and PCR ribotyping). Two of the patient isolates shared 100 per cent genetic homology by RAPD assay and another pair shared 100 per cent homology by PCR ribotyping. The five isolates from phacoemulsifiers did not share significant genetic homology. There was significant genetic variation between bacterial isolates from patients and phaco emulsifiers. Interpretation & conclusion: Though the three P. aeruginosa isolates obtained from the patients were phenotypically similar and genetically close, they differed from the phaco-machine isolates both genetically, and in their antibiogram profile. However, the five phacoemulsifier isolates were genetically diverse though they shared the same antibiogram profile. Therefore the Ringer’s lactate from phacomachines could not be conclusively proven to be the source of infection.

Preload with Ringer's Lactate Solution for Elective Cesarean Section : Effect on the Epidural Anesthesia Induced Hypotension / 대한마취과학회지

BACKGROUND: Hypotension associated with epidural anesthesia for cesarean section is common and serious, despite the use of uterine displacement and volume preload. This study evaluated the role of crystalloid volume preload for prevention of hypotension during epidural anesthesia. METHODS: Forty parturients undergoing elective cesarean section were allocated randomly to receive either no preload (Group II, n=20) or preload with Ringer's lactate solution 1000 ml over 10-15 minutes (Group I, n=20) before epidural anesthesia. Hypotension was defined as a decrease of systolic blood pressure to less than 90 mmHg and to less than 80% of baseline value. Systolic blood pressure and heart rate were measured 2 minutes interval during first 20 minutes after epidural injection. Apgar score, umbilical venous, arterial and maternal arterial blood gas analysis were done. RESULTS: Significant hypotension occured in seven of the twenty parturients in no preload group (Group II) and seven of twenty parturients in Ringer's lactate preload group (Group I). There were no statistical differences in systolic blood pressure, heart rate, amount of used ephedrine, Apgar score, umbilical venous, arterial and maternal arterial blood gas analysis. CONCLUSIONS: Ringer's lactate preload (1000 ml) before epidural anesthesia in the supine tilted parturients did not decrease the incidence or severity of hypotension.

The Effect of Preanesthetic Administration of Crystalloid for Prevention of Spinal Anesthesia-Induced Hypotension / 대한마취과학회지

BACKGREOUND: Despite many advantages of spinal anesthesia, hypotension after spinal anesthesia is a common complication. The practice of routine preemptive infusion of crystalloid before spinal anesthesia has been widespread acceptance. But the value of this practice has recently been questioned. This study was designed to determine whether preoperative administration of crystalloid decrease the incidence of hypotension after spinal anesthesia. METHODS: Thirty ASA I and II patients for elective lower extremities operations under spinal anesthesia were randomized to receive either 500 ml Ringer's lactate solution prior to induction of spinal anesthesia (group I) or no prehydration (group II). Hypotension was defined as a 30% decrease from baseline systolic blood pressure or systolic 70% of baseline, systolic blood pressure and heart rate were not significantly different between both groups. CONCLUSIONS: We conclude that, in normovolemic adult patients undergoing elective lower extremities surgery, an intravenous infusion of 500 ml of Ringer's lactate solution is ineffective in preventing hypotension during spinal anesthesia.

The Effect of Crystalduringloid Administration on Blood Pressure and Heart Rate Change during Epidural Anesthesia in Cesarean Section / 대한마취과학회지

BACKGROUND: Recently, epidural anesthesia for elective and emergency cesarean section is increasing in popularity and graudally replacing general anesthesia. However, the complications from the epidural anesthesia such as hypotension, dyspnea, nausea and vomiting have often been reported. This study was designed to estimate the efficacy of crystalloid administration on blood pressure and heart rate change during epidural anesthesia in cesarean section. METHODS: Forty ASAI and II patients scheduled for cesarean section under epidural anesthesia were randomly allocated to receive either only maintained fluid administration(group I) or 15 ml/kg crystalloid solution over 15 minutes(group II). Epidural anesthesia was performed in a lateral decubitus position. According to the patient's height, 20~23 ml of 2% lidocaine was injected through epidural catheter at the L3~4 interspace. RESULTS: Cardiovascular responses and complications after induction of epidural anesthesia were compared and results were as follows. The incidence of hypotension was 14/20 (70%) in the groupI and 4/20(25%) in the group II(p<0.05). Systolic blood pressure after induction of epidural anesthesia in the group I significantly decreased from 6 min to 12 min as compared to the group II. The mean heart rate after induction of epidural anesthesia in the both group was no significant difference to baseline heart rate. CONCLUSIONS: Considering above results, we conclude that a prophylactic crystalloid solution infusion is effective for minimizing and managing hypotension associated with epidural anesthesia in cesarean section.

Intravenous oxygenation with lactated Ringer's solution

This experimental work was performed on 4 rabbits to demonstrate that administrations of oxygenated Ringer's lactate through the central venous infusion could be used as a means of oxygenation. The oxygen tensions of Ringer's lactate were determined upon changing the amount of oxygen being bubbled and the solutions with the mean PO2 and pH of 575.5 mmHg and 6.34 were used in this study. We did not use the solutions having the values below 416.6 mmHg PO2 and pH 6.08. After the infusion of the oxygenated solution through central vein, PaO2 values throughout the 1 hour experimental procedure were significantly increased above the control value. Other parameters such as pH, PaCOs, HCO3-, BE, O2 saturation did not show any statistically significant changes. Some degree of oxygenation could be obtained by infusing the oxygenated Ringer's solution. This suggested that oxygenation by infusion through the central venous line could used clinically in the treatment of some forms of hypoxia with hypovolemia.

Transperitoneal Oxygenation with Lactated Ringer's Solution

This experimental study was performed on 5 rabbits to ascertain if oxygenated Ringer's lactate Could be used in place of fluorocarbons through peritoneal administration. Oxygen was bubbled through solutions of Ringer's lactate at two different rates and the oxygen tension of each solution was determined. The solution used in vivo had oxygen delivered at a rate of 5 L/min; the mean PO2 and pH were 575.5 mmHg and 6.34 respectively, while the rate of oxygenation of the in vitro solution was 3 L/min. with a mean PO2 and pH of 416.6 mmHg and 6.08. After peritoneal administration of the oxygenated solution the PaO2 values were significantly increased from the control value. Other parameters such as pH, PaCO2, HCO3, BE, SO2 (oxygen saturation), Na and K were not shown to be statistically significant. Some degree of oxygenation could be obtained by the introduction of oxygenated Ringer's solution. This result suggested that this solution can be used for oxygenation via the transperitoneal administration, and that this method of oxygenation may possibly be used to treat some forms of respiratory failure.