Chromatographic study of sitagliptin and ertugliflozin under quality-by-design paradigm

Abstract The present study entails the systematic development and validation of a stability-indicating RP-HPLC method for the analysis of sitagliptin and ertugliflozin in a fixed-dose combination. Analytical quality by design (AQbD) concepts were used to define critical method variables, employing Pareto risk assessment and a Placket-Burman screening design, preceded by a Box-Behnken design with response surface analysis to optimise critical method parameters such as % acetonitrile (X1), buffer pH (X2) and column oven temperature (X3). Multiple response optimisation (Derringer's desirability) of variables was accomplished by studying critical analytical attributes, such as resolution, retention time and theoretical plates. The title analytes were separated effectively on a PRONTOSIL C18 column at 37 °C using a mobile phase of acetonitrile:acetate buffer, pH 4.4 (36:64 percent v/v), pumped at a flow rate of 1 mL/min, and UV detection at 225 nm. Linearity was observed over a concentration range of 25-150 µg/mL and 3.75-22.5 µg/mL at retention times of 2.82 and 3.92 min for sitagliptin and ertugliflozin, respectively. The method obeyed all validation parameters of the ICH Q2(R1) guidelines. The proposed robust method allows the study of the selected drugs in pharmaceutical dosage forms as well as in drug stability studies under various stress conditions.

Preparation and evaluation of 2-methoxyestradiol-loaded pH-sensitive liposomes

The development and clinical application of 2-methoxyestradiol (2-ME) as a new type of antitumor drug are limited due to its poor solubility, rapid metabolism in vivo, and large oral dosage. 2-ME-loaded pH-sensitive liposomes (2-ME-PSLs) was prepared containing the lipids, Lipoid E-80 (E-80), cholesteryl hemisuccinate (CHEMS), and cholesterol (CHOL) via thin-film ultrasonic dispersion. First, preparation conditions of 2-ME-PSLs were optimized by orthogonal test. Then 2-ME-PSL was characterized, and the release behavior and stability of 2-ME-PSL in vitro were evaluated. The optimal preparation conditions for 2-ME-PSLs were as follows: 2-ME : E-80+CHEMS 1:15; CHOL : E-80+CHEMS 1:5; ultrasonication time 20 minutes. The mean particle size, PDI, zeta potential, and entrapment efficiency (EE) of 2-ME-PSLs were 116 ± 9 nm, 0.161 ± 0.025, −22.4 ± 1.7 mV, and 98.6 ± 0.5%, respectively. As viewed under a transmission electron microscope, 2-ME-PSLs were well dispersed and almost spherical. They exhibited significant pH-sensitive properties and were fairly stable when diluted with a physiological solution. In conclusion, 2-ME-PSLs were successfully prepared and possessed a favorable pH sensitivity and good dissolution stability with a normal solution

Effect of pH on weakly acidic and basic model drugs and determination of their ex vivo transdermal permeation routes

ABSTRACT The aim of the present study was to investigate the effect of donor pH on the transdermal permeability of the model drugs across rat skin and also to determine the major route of transport of the drugs. Weakly acidic drugs (partition coefficient) ibuprofen (3.6), aceclofenac (3.9), glipizide (1.9) and weakly basic drugs olanzapine (3.6), telmisartan (6.0), and sildenafil citrate (1.9) were selected for the study. The ex vivo permeation studies of these drugs at different donor pH (pH - 1.2, 4, 5, 6.8, 7.4, and 8) using Franz diffusion cell (area, 7.54 cm2) has shown a pH-dependent permeability. Among these drugs the weakly acidic drugs has shown higher permeation rates compared to the weakly basic drugs. The permeability coefficient and the distribution coefficient of the weakly basic drugs increased on increasing the pH whereas the weakly acidic drugs showed an inverse relation. The weakly basic drugs also showed an increase in permeation with increase in the fraction of unionized species indicating dominance of transcellular route of permeation. With an exception of sildenafil citrate, a weakly basic salt form of the drug which showed a high permeation value at pH 7.4 where 57% of the drug was unionized, indicating the involvement of both paracellular and transcellular route in its permeation.

Influence of 2% chlorhexidine on pH, calcium release and setting time of a resinous MTA-based root-end filling material

The addition of chlorhexidine (CHX) to a resinous experimental Mineral Trioxide Aggregate (E-MTA) based root-end filling material is an alternative to boost its antimicrobial activity. However, the influence of chlorhexidine on the properties of this material is unclear. The aim of this study was to evaluate the influence of 2% chlorhexidine on the pH, calcium ion release and setting time of a Bisphenol A Ethoxylate Dimethacrylate/Mineral Trioxide Aggregate (Bis-EMA/MTA) based dual-cure experimental root-end filling material (E-MTA), in comparison with E-MTA without the addition of CHX and with conventional white MTA (W-MTA). The materials were placed in polyethylene tubes, and immersed in deionized water to determine pH (digital pH meter) and calcium ion release (atomic absorption spectrometry technique). The setting time of each material was analyzed using Gilmore needles. The data were statistically analyzed at a significance level of 5%. E-MTA + CHX showed an alkaline pH in the 3 h period of evaluation, the alkalinity of which decreased but remained as such for 15 days. The pH of E-MTA + CHX was higher than the other two materials after 7 days, and lower after 30 days (p < 0.05). All of the materials were found to release calcium ions throughout the 30 days of the study. The addition of CHX increased the calcium ion release of E-MTA to levels statistically similar to W-MTA. E-MTA showed shorter initial and final setting time, compared with W-MTA (p < 0.05). The addition of 2% CHX to MTA prevented setting of the material. The addition of CHX to E-MTA increased its pH and calcium ion release. However, it also prevented setting of the material.

Análise da variação do pH de três pastas à base de hidróxido de cálcio, quando associadas ao PMCC, clorexidina e aloe vera / Analysis of the pH variation of three calcium hydroxide-based pastes, when associated with CMCP, chlorhexidine and aloe vera

O objetivo deste estudo, in vitro, foi analisar a variação do pH de três pastas à base de Ca(OH)2 e de cada um de seus componentes. Foram formados quatro grupos teste: GI: Ca(OH)2 + propilenoglicol (PG) + Aloe vera; GII: Ca(OH)2 + PG + paramonoclorofenol canforado (PMCC); GIII: Ca(OH)2 + PG + clorexidina 2% e grupo controle (água destilada). As pastas foram depositadas em frascos contendo 15 ml de água destilada e estes armazenados em estufa a 37° C. A mensuração do pH foi realizada em 7 intervalos de tempo. Os grupos testados apresentaram crescimento exponencial dos valores de pH registrados até 24 h e estabilização em 14 dias. Os controles apresentaram valores de pH inferiores em relação aos demais grupos (p<0,05 ­ ANOVA). A partir de t = 24 h, GII e GIII apresentaram maiores valores de pH em relação a GI (p<0,05 ­ Bonferroni). Numa segunda etapa, foram formados cinco grupos com os componentes individuais de cada pasta: GIc ­ clorexidina líquida 2%; GIIc ­ PG; GIIIc ­ PMCC; GIVc ­ hidróxido de cálcio P.A.; GVc ­ Aloe vera. GIVc e GVc apresentaram, respectivamente, os maiores e menores valores de pH registrados até o final do experimento (12,63 e 5,54). Conclui-se que o pH das pastas de Ca(OH)2 pode variar em função da sua composição, porém sempre se mantendo alcalino, mesmo quando associada à Aloe vera, cujo pH ácido foi registrado no presente estudo. No entanto, uma maior alcalinidade foi apresentada pelas pastas contendo clorexidina ou PMCC em sua composição.

The objective of this study, in vitro, was to analyze the variation of the pH of threeCa(OH)2 - based pastes and each of its components. There were four groups test: GI: Ca(OH)2 + propylene glycol (PG) + Aloe vera; GII: Ca(OH)2 + PG + camphorated paramonochlorophenol (CMCP); GIII: Ca(OH)2 + PG + 2% chlorhexidine and control group (distilled water). The pastes were deposited in vials containing 15 ml of distilled water and stored in a 37° C incubator. The measurement of pH was performed in 7 time intervals.The groups tested showed exponential growth of pH values recorded up to 24 h and stabilization in 14 days. The controls showed pH values lower than the other groups (p<0.05 ­ ANOVA). From t = 24 h, GII and GIII had higher levels of pH compared to GI (p<0.05 - Bonferroni). Subsequently, five groups were formed with the individual components of each paste: GIc - 2% chlorhexidine liquid; GIIc - PG; GIIIc - CMCP; GIVc - calcium hydroxide; GVc - Aloe vera. GIVc and GVc showed, respectively, the highest and lowest pH values recorded by the end of the experiment (12.63 and 5.54). It was concluded that the pH of Ca(OH)2 pastes may change depending on their composition, but always remained alkaline, even when associated with Aloe vera, whose acidic pH was recorded in this study. However, a higher alkalinity was presented by pastes containing chlorhexidine or CMCP in its composition.

Saliva and tongue coating pH before and after use of mouthwashes and relationship with parameters of halitosis

OBJECTIVES: The aim of this work was to evaluate saliva and tongue coating pH in oral healthy patients with morning bad breath before and after use of different oral mouthrinses. MATERIAL AND METHODS: Saliva and tongue coating pH of 50 patients allocated in 5 groups were measured respectively by a digital pHmeter and color pH indicators, before, immediately after and 30 min after rinsing 5 different mouthrinses: cetilpiridine chloride associated with sodium chloride, triclosan, enzymatic solution, essential oil and distilled water. RESULTS: Only triclosan and essential oil increased salivary pH immediately after rising. The enzymatic solution decreased salivary and tongue coating pH immediately after rinsing. CONCLUSIONS: Salivary pH tended to be acidic while tongue coating pH tended to be alkaline, even after rising. Triclosan and essential oil mouthrinses increased salivary pH immediately after rinsing. Enzymatic solution decreased saliva and tongue coating pH immediately after rising.

The effect of epidural and general anesthesia on newborn rectal temperature at elective cesarean section

Both epidural and general anesthesia can impair thermoregulatory mechanisms during surgery. However, there is lack of information about the effects of different methods of anesthesia on newborn temperature. The purpose of this study was to determine whether there are differences in newborn rectal temperature related to type of anesthesia. Sixty-three pregnant women were randomly assigned to receive general or epidural anesthesia. Maternal core temperature was measured three times with a rectal probe just before anesthesia, at the beginning of surgery and at delivery. In addition, umbilical vein blood was sampled for pH. The rectal temperatures of the babies were recorded immediately after delivery, and Apgar scores were determined 1, 5, and 10 min after birth. The duration of anesthesia and the volume of intravenous fluid given during the procedure (833 ± 144 vs 420 ± 215 mL) were significantly higher in the epidural group than in the general anesthesia group (P < 0.0001). Maternal rectal temperatures were not different in both groups at all measurements. In contrast, newborn rectal temperatures were lower in the epidural anesthesia group than in the general anesthesia group (37.4 ± 0.3 vs 37.6 ± 0.3°C; P < 0.05) immediately after birth. Furthermore, the umbilical vein pH value (7.31 ± 0.05 vs 7.33 ± 0.01; P < 0.05) and Apgar scores at the 1st-min measurement (8.0 ± 0.9 vs 8.5 ± 0.7; P < 0.05) were lower in the epidural anesthesia group than in the general anesthesia group. Since epidural anesthesia requires more iv fluid infusion and a longer time for cesarean section, it involves a risk of a mild temperature reduction for the baby which, however, did not reach the limits of hypothermia.

Strawberry (Fragaria X ananassa Duch. ) yiel das affected by the soil pH

Two-year trials (20062007) suggested that the use of calcium oxide (CaO) on acid soils increased soil pH and yields in strawberry cultivars Marmolada, Selena and Senga Sengana, under the environmental conditions of Cacak (Western Serbia). The highest yield was obtained when CaO was applied at 750 kg ha-1 rate. Further increase in rate up to 1,500 kg ha-1 did not show corresponding increase in yield; the result was a slight yield drop compared to the peak yield shown at 750 kg ha¹ rate. Overall, yields at rates above 750 kg ha¹ were still higher than control and in the treatment employing lowest CaO application rate of 250 kg ha-1.

Dois anos de ensaios (2006-2007) sugeriram que o uso deóxido cálcio (CaO) em solos ácidos aumentou o pH do soloe o rendimento das cultivares de morango, Marmolada, Selena e Senga Sengana, sob as condições ambientais de Cacak (oeste da Sérvia). O rendimento mais elevado foi obtido quando CaO foi aplicado na quantidade de 750 kg ha-1. O aumento da quantidade para nível até 1500 kg ha-1 não mostrouaumento correspondente do rendimento; o resultado foi umaligeira queda em comparação com o rendimento máximo obtidoa 750 kg ha¹. Globalmente, os resultados a taxas superiores a 750 kg ha¹ foram ainda mais elevados do que no controle e no tratamento empregando quantidade mais baixa de 250 kg ha-1 de CaO.

Antiretroviral agents and acid-base balance at delivery of the neonate

Limited evidence is available regarding antiretroviral (ARV) safety for uninfected infants exposed to these drugs in utero. Our objective was to determine if ARV administered to pregnant women is associated with decreasing umbilical arterial pH and base excess in uninfected infants. A prospective study was conducted on 57 neonates divided into three groups: ZDV group, born to mothers taking zidovudine (N = 20), triple therapy (TT) group, born to mothers taking zidovudine + lamivudine + nelfinavir (N = 25), and control group (N = 12), born to uninfected mothers. Umbilical cord blood was used to determine umbilical artery gases. A test was performed to calculate the sample by comparing means by the unpaired one-tailed t-test, with a = 0.05 and ß = 20 percent, indicating the need for a sample of 18 newborn infants for the study groups to detect differences higher than 20 percent. The control and ARV groups were similar in gestational age, birth weight, and Apgar scores. Values of pH, pCO2, bicarbonate, and base excess in cord arterial blood obtained at delivery from the newborns exposed to TT were 7.23, 43.2 mmHg, 19.5 mEq/L, and -8.5 nmol/L, respectively, with no significant difference compared to the control and ZDV groups. We conclude that intrauterine exposure to ARV is not associated with a pathological decrease in umbilical arterial pH or base excess. While our data are reassuring, follow-up is still limited and needs to be continued into adulthood because of the possible potential for adverse effects of triple antiretroviral agents.

Effect of habitual arecanut chewing on resting whole mouth salivary flow rate and pH.

BACKGROUND: Resting whole mouth salivary flow rate (SFR) and pH play a significant role in pathogenesis of various oral diseases and conditions. AIM: To observe the effect of habitual use of arecanut and various arecanut containing products (AN) on SFR and pH. DESIGN: Cross sectional. SETTING: Outpatient Department of Dental College. PARTICIPANTS: AN chewers and non-chewers attending Dental college. MEASUREMENTS: SFR and pH. VARIABLES: Type, frequency, duration and exposure time of AN, Smoking and Alcohol habit. MATERIALS AND METHODS: Subjects study was divided into chewers (n=110) and non- chewers (n=50). The SFR (expressed in mL/10min) and pH measured. RESULTS: The difference between the mean SFR for chewers and non-chewers was not statistically significant. The difference between mean pH of chewers and non-chewers was statistically significant. (P=0.02). Difference in pH was statistically significant among the different types of AN chewers (P=0.024). With chewing raw AN, an increase in frequency and exposure time increased SFR and pH respectively. In processed AN chewers, increase in duration and frequency of consumption increased SFR and decreased pH respectively. For chewers with betel quid with tobacco, increase in duration was significantly associated with decrease in salivary pH. CONCLUSION: SFR and pH are altered in AN chewers, rendering the oral mucosa vulnerable to the toxic effects of AN.

Estudo comparativo do pH e do volume salivar em indivíduos com laringofaringite crônica por doença do refluxo gastroesofágica antes e após o tratamento / Comparative study of salivary pH and volume in adults with chronic laryngopharyngitis by gastroesophageal reflux disease before and after treatment

INTRODUÇÃO: A Doença do Refluxo Gastroesofágico (DRGE) é a doença digestiva mais prevalente da atualidade e, recentemente, tem sido implicada em uma gama de alterações do seguimento laringofaríngeo (RLF). No entanto, pouco se sabe dos mecanismos fisiopatológicos destas manifestações supraesofágicas da DRGE. Os achados clínicos contraditórios e recentes pesquisas sugerem haver deficiências na capacidade de defesa deste seguimento. Uma das principais responsáveis pela homeostase da mucosa oral e do trato digestivo é a saliva com seu conteúdo orgânico e inorgânico. Tanto alterações do pH quanto do volume salivar já foram correlacionados com os sintomas e sinais sugestivos da DRGE e RLF. Estudo recente de nossa autoria demonstra diminuição estatisticamente significante do pH salivar de indivíduos com RLF quando comparado a controles sem a doença. Outro estudo constatou correlação entre a redução do volume X pH da saliva em indivíduos com DRGE, estando esta redução diretamente relacionada aos níveis de pH esofágico constatados durante pH-metria esofágica de 24 horas. OBJETIVOS: Avaliar como se comportam o pH e volume da saliva em um mesmo indivíduo com DRGE e RLF antes e após o tratamento clínico. MATERIAL E MÉTODO: Vinte e três pacientes com RLF tiveram o pH e volume da saliva total testados antes e após receberem tratamento com droga bloqueadora de bomba de prótons durante 12 semanas. RESULTADOS: Houve uma diferença estatisticamente significante (p<0,001) entre o pH da saliva antes e após o tratamento, estando este maior após o controle clínico da doença. O volume de saliva no paciente tratado foi significativamente maior do que no paciente pré-tratamento (p=0.009). DISCUSSÃO: Os achados sugerem que o pH salivar é influenciado pela presença de refluxo gastroduodenal à região laringofaríngea. Caso estudos futuros com populações maiores realmente comprovem esta correlação, poderemos cogitar a possibilidade de usar a mensuração do pH salivar, que é feita de forma rápida e não invasiva, como um meio de diagnosticar e avaliar o comportamento e controle do Refluxo Laringofaríngeo.

INTRODUCTION: Gastroesophageal Reflux Disease (GERD) is the most prevalent digestive disease of the modern society and has been associated with abnormalities in the larynx and pharynx (LPR). Nonetheless, little is known about the mechanisms involved in this atypical form of the disease. Contradictory clinical data suggest a defense deficit at this segment. Saliva with its organic and inorganic components is responsible for the homeostasis of the oral mucosa and the digestive tract. Salivary pH and volume abnormalities have been linked to laryngopharyngeal symptoms of GERD and LPR. In a recent study we demonstrated significant salivary pH reduction in patients with LPR. Another study found correlation between reduced salivary pH and volume directly related to esophageal pH-metry results. AIM: To evaluate salivary pH and volume before and after clinical treatment of LPR. MATERIAL AND METHOD: Twenty-three adults with LPR had total fasting saliva tested before and after a 12-week course of oral proton pump inhibitor. RESULTS: A statistically significant difference was found in salivary pH before and after treatment with increase of pH values after control of the disease (p<0.001). Salivary volumes of treated patients were also significantly higher than in pre-treated patients (p=0.009). DISCUSSION: These findings suggest that salivary pH and volume are influenced by the presence of gastroesophageal contents and that salivary pH monitoring can potentially become a cost-effective method for diagnosing and controlling LPR.

Catecholamine-induced vasoconstriction is sensitive to carbonic anhydrase I activation

We studied the relationship between alpha- and beta-adrenergic agonists and the activity of carbonic anhydrase I and II in erythrocyte, clinical and vessel studies. Kinetic studies were performed. Adrenergic agonists increased erythrocyte carbonic anhydrase as follows: adrenaline by 75 percent, noradrenaline by 68 percent, isoprenaline by 55 percent, and orciprenaline by 62 percent. The kinetic data indicated a non-competitive mechanism of action. In clinical studies carbonic anhydrase I from erythrocytes increased by 87 percent after noradrenaline administration, by 71 percent after orciprenaline and by 82 percent after isoprenaline. The increase in carbonic anhydrase I paralleled the increase in blood pressure. Similar results were obtained in vessel studies on piglet vascular smooth muscle. We believe that adrenergic agonists may have a dual mechanism of action: the first one consists of a catecholamine action on its receptor with the formation of a stimulus-receptor complex. The second mechanism proposed completes the first one. By this second component of the mechanism, the same stimulus directly acts on the carbonic anhydrase I isozyme (that might be functionally coupled with adrenergic receptors), so that its activation ensures an adequate pH for stimulus-receptor coupling for signal transduction into the cell, resulting in vasoconstriction

A randomized clinical trial comparing the efficacy of ranitidine and famotidine on intragastric acidity in critically ill pediatric patients.

We examined the efficacy of intravenous ranitidine and famotidine on raising intragastric pH in each of 10 critically ill pediatric patients. The severity of illness was assessed by using the modified zinner index score. The study had 3 phases and each phase took 24 hours. Intragastric pH was measured by continuous pH monitoring digitrapper for 72 hours. In phase 1 and 3, the patients did not receive any H2 blockers. In phase 2, they were randomized to receive intravenous ranitidine or famotidine. The majority of cases had intragastric pH < 4 in day 1 (base line). Ranitidine and famotidine increased total time of intragastric pH > or = 4 from the base line during day 2, 38.2 +/- 16.9 per cent and 60.3 +/- 24.8 per cent respectively (P0.004), but there was no statistical difference between the 2 medications in both Zinner index score 1 and score greater than 1 group (P 0.08, 0.45). Three cases in the famotidine group had successful prophylaxis with total time pH > or = 4 more than 80 per cent. Famotidine appeared to have a trend toward increasing intragastric pH in critically ill pediatric patients.

Calcium and phosphate solubility curves for parenteral nutrient solutions containing Vaminolact.

Calcium and phosphate incompatibility in the total parenteral nutrient (TPN) solutions is a common problem especially in neonates. Their combinations in TPN admixture must be tested before use. We here investigated the compatibility of calcium and phosphate in TPN solutions containing a newborn amino acid product, Vaminolact. The TPN test-solutions contained 10 per cent dextrose, 1, 2, or 3 per cent Vaminolact, 4 mmole/L of magnesium sulphate and various combinations of calcium gluconate and dipotassium phosphate. Precipitations and crystallizations were inspected visually and microscopically after 24 hours standing at room temperature. Solubility curves were made by plotting the maximum concentrations of calcium and phosphate at which both were still compatible in the solution. Such curves are extremely helpful for clinicians and pharmacists to administer maximum calcium and phosphate dose for individual patient requirement.

Effects of chronic treatments with adrenal steroids on acid-base homeostasis in the rat

Urinary parameters related to acid base homeostasis were studied in adrenalectomized rats (ADX) as well as in ADX treated with physiological doses of corticosterone (B), aldosterone (aldo) or 18-Hydroxycorticosterone (l8HOB) during 1,3 or 5 days, under basal conditions and after gravage with 200 mM HCI. The results showed: a) a persistent effect of B and l8HOB increasing titratable acidity principally in response to acidosis; b) an increased phosphate elimination in acidotic B treated ADX on the first day, and in 18 HOB treated ADX on days 3 and 5; c) pronounced increases in blood pH and blood bicarbonate levels provoked by the three steroids on day 1; d) increments of ammonium elimination in response to acidosis by aldo treatmets on the first day, while B and l8HOB increase ammonium elimination under almost all conditions during the whole experiment; e) the effects of B and 18 HOB would be independent of an increase in sodium retention as well as glomerular filtration rate.

Effects of tunicamycin on the pH-activity pattern of acid phosphatase in Pseudomonas pseudomallei.

The liquid culture of Pseudomonas pseudomallei shows a complex feature in in the pH-activity pattern of acid phosphatase, not a single peak curve. There was an evident tendency that the higher activity shifted to the higher pH range with the growth of culture. The culture in the presence of tunicamycin (20 micrograms/ml) showed a decreased activity selectively in the higher pH range, while the activity in the lower pH was more heat-labile. The bacterial cells grown on agar plates containing tunicamycin were more heat-labile than the untreated control cells. The glucosidase-treatment reduced the enzymatic activity (of the phosphatase-active fractions from the living cells) with the shift of the optimum pH to lower pH. These observations together with some collateral findings suggest that the pH-activity pattern of acid phosphatase in P. pseudomallei is associated with the development of precursor enzyme proteins to mature glycoproteins.

Valoración de la microperfusión esplánica en el postoperatorio inmediato de pacientes críticos / Splanchnic microperfusion evaluation in the postoperative of surgical ill patients

En la presente comunicación se analiza la relación existente entre el estado de la microperfusión esplánica y la incidencia de fallas orgánicas, sepsis y mortalidad, en el postoperatorio de pacientes quirúrgicos críticos. El flujo esplánico fue evaluado directamente a través de la medición del pH intracelular de la mucosa gástrica (pHi). Se estudiaron en forma prospectiva 125 pacientes críticos, operados por patología abdominal. El pHi se midió durante las primeras 24 horas del postoperatorio mediante un tonómetro ubicado en la cavidad gástrica. Se diferenciaron dos grupos de enfermos, Grupo I: con todas las mediciones de pHi superiores a 7.40 y Grupo II: con una o más determinaciones iguales o inferiores a 7.40. La sumatoria de puntos Apache II y el promedio de falls orgánicas fueron significativamente inferiores en el Grupo I (12.6 y 0.4 respectivamente vs. 16.1 y 1.1 respectivamente en el Grupo II) con una p<0.01. Fallecieron 39 pacientes (31.2//). El pHi fue significativamente superior en los sobrevivientes, a partir de las 6 horas del postoperatorio. Otros parámetros habitualmente utilizados para evaluar la gravedad, no mostraron diferencias significativas en ese momento de la evolución. La incidencia de fallas orgánicas y sepsis fue mayor en los fallecidos. La medición del pHi en las primeras 24 horas del postoperatorio fue útil para predecir la evolución de los pacientes

Estudio en doble ciego con famotidina: pH y volumen gástrico / Study in double blind with famotidine: pH and gastric volume

Estudio prospectivo, aleatorio y en doble ciego. Noventa pacientes sometidos a cirugía abdominal recibieron preoperatoriamente 20 mg de famotidina intravenosa o un placebo. Se midió el pH y volumen gástrico postintubación traqueal (T1), al momento del vaciamiento total del estómago (T2) y antes de la extubación (T3). El pH gástrico fue significativamente superior en el grupo de pacientes que recibió famotidina en los tres tiempos de medición. El volumen gástrico fue significativamente inferior en el grupo con famotidina en el tiempo 1, no habiendo diferencia entre los dos grupos en los tiempos 2 y 3. La población "en riesgo" (pH < 3 y volumen > 25 ml) fue significativamente inferior en el grupo que recibió famotidina en los tres tiempos de medición