The clinical significance of cervical tears' anatomical location - A retrospective study

OBJECTIVE

Up to 4.8% of all vaginal deliveries are complicated by significant cervical tears related to maternal compromise, yet the location of the cervical tear and its impact on the attributed risk have not been studied to date. This study aimed to determine the associations between the location and characteristics of cervical tears with short-term maternal complications and outcomes.

METHODS

This is a retrospective cohort study. Included were all patients that delivered vaginally at our institute between the years 2009-2020 and were diagnosed with a cervical tear. Maternal complications were compared between cases with posterior cervical tears and cases with anterior or lateral cervical tears. Exclusion criteria included patients who delivered by cesarean delivery and preterm labor below 37.0 weeks of gestation.

RESULTS

Overall, 96 patients were diagnosed with posterior cervical tears, while 117 patients were diagnosed with anterior or lateral tears. Maternal demographics and pregnancy characteristics were similar between the groups. There were also no differences in delivery outcomes between the groups. Patients with posterior cervical tears had a higher rate of disseminated intravascular coagulation (DIC) (6.25 % vs. 0.9 %, p = 0.04) and prolonged hospitalization (35.4 % vs. 23.1 %, p = 0.05), as compared to patients with anterior or lateral tears. There were no differences in other maternal complications.

CONCLUSIONS

Cases of posterior cervical tears are at higher risk for maternal adverse outcomes (DIC and prolonged hospitalization), as compared to cases of anterior or lateral tears.

Improved neonatal outcomes in pregnancies with coexisting gestational diabetes and preeclampsia in normal birthweight neonates- insights from a retrospective cohort study

INTRODUCTION

We aimed to assess neonatal and maternal outcomes in appropriate-for-gestational-weight (AGA) neonates of mothers with both gestational diabetes mellitus (GDM) and preeclampsia (PET).

METHODS

Medical records of women diagnosed with GDM or PET were reviewed. Women with AGA neonates were divided into three groups- GDM, PET, and GDM + PET and maternal neonatal and placental outcomes were compared. The primary outcome was a composite of adverse neonatal outcomes, including intensive care unit admission (NICU), neurological morbidity, hypoglycemia, ventilation, respiratory distress syndrome (RDS), phototherapy, sepsis, blood transfusion, and neonatal death. Post-hoc analysis was performed to determine between-group significance.

RESULTS

Composite adverse neonatal outcomes are significantly lower in women with multiple morbidities compared to women with confined PET (p = 0.015), and a similar trend is observed when comparing neonatal outcomes between women with GDM to those with GDM + PET, yet these results are underpowered (18.9 % vs. 12.8 % respectively, p = 0.243). Placentas of women with GDM + PET were larger, with a lower rate of placentas below the 10th percentile as compared to placentas of women with isolated PET (p < 0.001), but with similar rates of MVM lesions.

DISCUSSION

While maternal and placental outcomes in patients of the GDM + PET group resemble the characteristics of the PET group, surprisingly, the neonatal outcomes in this group are significantly better compared to isolated morbidities. The paradoxical benefit attributed to the coexistence of GDM + PET may be explained by a balance of the opposing trends characterizing these morbidities-the reduced blood and nutrient supply characterizing PET vs. chronic overflow and abundance typical of GDM.

CLINICAL TRIAL REGISTRATION

approval of local ethics committee WOMC-19-0152.

Does the combination of four OGTT values enhance the prediction of adverse pregnancy outcomes? Insights from a retrospective cohort study

AIM

To explore the correlation between a singular value of additive OGTT scores and adverse maternal and neonatal outcomes. We postulated that a higher additive OGTT score would predict poorer maternal and neonatal outcomes.

METHODS

In this retrospective cohort study, data were collected from all women with a documented complete OGTT result and subsequent diagnosis of GDM. The additive OGTT score was calculated by adding each individual hourly glucose measurement. Maternal demographics, pregnancy and labor characteristics, and neonatal outcomes were compared between the lower-sum and higher-sum OGTT groups. A multivariate regression analysis was performed to identify confounders associated with adverse outcomes.

RESULTS

In this study, a total of 1497 patients were assessed. The group with higher-sum OGTT scores was characterized by increased rates of GDMA2 (p = 0.008), higher insulin doses (p = 0.009), and higher rates of composite maternal and neonatal adverse outcomes (p = 0.021 and p = 0.030, respectively) compared to the lower-sum OGTT group.

CONCLUSION

The additive OGTT score may aid in predicting the need for insulin treatment, labor course, and neonatal outcomes in GDM patients.

The use of virtual reality during extra-amniotic balloon insertion for pain and anxiety relief-a randomized controlled trial

BACKGROUND

Induction of labor with an extra-amniotic balloon catheter is a procedure commonly associated with maternal discomfort, pain, and anxiety.

OBJECTIVE

We aimed to investigate the distractive effect of virtual reality technology on pain and anxiety among pregnant patients who underwent induction of labor with an extra-amniotic balloon catheter.

STUDY DESIGN

In this randomized controlled trial, pregnant patients who were undergoing planned induction of labor using an extra-amniotic balloon catheter at term for various obstetrical indications were recruited and randomized in a 1:1 ratio into 2 groups. Patients in the virtual reality group were exposed to a virtual reality technology clip (using SootheVR All-In-One virtual reality care system for pain and anxiety) during the entire extra-amniotic balloon catheter insertion, whereas patients in the control group received the institutional standard care for extra-amniotic balloon catheter insertion. Pain scores, expressed as visual analog scale scores, and maternal hemodynamic parameters were obtained before, during, and after extra-amniotic balloon catheter insertion. Anxiety was evaluated using the validated State-Trait Anxiety Inventory Scale before and after the procedure. Maternal satisfaction with the virtual reality technology was also recorded. The primary outcome was the change in visual analog scale score before and during extra-amniotic balloon catheter insertion. Among the secondary outcomes was the change in anxiety levels before and after extra-amniotic balloon catheter insertion. The study was powered to detect a 25% decrease in the primary outcome.

RESULTS

A total of 132 pregnant patients were recruited (66 in each group). There were no differences between groups in terms of age, body mass index, gestational age at enrollment, indication for induction of labor, and preprocedural visual analog scale score and anxiety levels. The change in visual analog scale score (maximal visual analog scale score during the procedure minus the initial visual analog scale score before the procedure, ie, the primary outcome) was significantly lower in the virtual reality group than in the control group (2.78±3.0 vs 4.09±2.99; P=.01). In addition, the virtual reality group experienced a higher rate of anxiety relief, expressed as the difference between the preprocedure and postprocedure State-Trait Anxiety Inventory Scale scores (-6.46±9.6 vs -2.01±9.11; P=.007). Patients in the virtual reality group reported a very high overall (94%) satisfaction score.

CONCLUSION

In this randomized controlled trial, we demonstrated that the use of virtual reality technology among patients who underwent induction of labor using an extra-amniotic balloon catheter was associated with lower visual analog scale scores during the procedure and a significant reduction in anxiety than patients who received standard care. There was also a very high satisfaction rate with the use of virtual reality technology.

The effect of watching an informational video prior amniocentesis on maternal anxiety: a randomized controlled trail

PURPOSE

This randomized controlled trial aimed to ascertain the effect of a pre-procedure informational video on anxiety, pain perception, and satisfaction levels in patients undergoing amniocentesis.

METHODS

Patients were randomized into two groups: a video group who watched an informational video prior to the procedure, and a control group who received standard care. Anxiety was gauged both pre- and post-procedure via the State-Trait Anxiety Inventory (STAI) score. Post-procedure, patients' perceived pain, anxiety, and satisfaction levels were evaluated using the Visual Analog Scale questionnaire (VAS).

RESULTS

Of 110 randomized patients, 100 completed the study and were included in the final analysis. No significant difference was noted in overall anxiety levels between the study and control groups. However, in-procedure anxiety was significantly lower in the video group compared to the control group (p = 0.04). Among patients undergoing amniocentesis for the first time, the subgroup analysis revealed reduced levels of anxiety during the procedure and diminished pain 10 min after the procedure in the video group compared to the control group. (p = 0.041 and p = 0.025, respectively).

CONCLUSION

A pre-procedural informational video could help in alleviating anxiety and mitigating pain during amniocentesis.

CLINICAL TRIAL REGISTRATION

The study was registered at 27.3.2022 in clinical-trials.gov (identifier NCT05463549).

Pregnancy and placental outcomes according to maternal BMI in women with preeclampsia: a retrospective cohort study

PURPOSE

Obesity and preeclampsia share similar patho-mechanisms and can both affect placental pathology. We aimed to investigate pregnancy outcomes in correlation with placental pathology among pregnancies complicated by preeclampsia in three different maternal body mass index (BMI, kg/m²) groups.

METHODS

In this retrospective cohort study, medical and pathological records of patients with preeclampsia and a singleton pregnancy delivered between 2008 and 2021 at a single tertiary medical center were reviewed. Study population was divided into three BMI groups: BMI < 22.6 kg/m² (low BMI group), 22.7 ≤ BMI ≤ 28.0 kg/m² (middle-range BMI group), and BMI > 28.0 kg/m² (high BMI group). Data regarding maternal characteristics, neonatal outcomes, and placental histopathological lesions were compared.

RESULTS

The study groups included a total of 295 patients diagnosed with preeclampsia-98, 99, and 98 in the low, middle-range, and high BMI groups respectively. Neonatal birth weight was significantly decreased in the low maternal BMI group compared to both middle and high BMI groups (p = 0.04) with a similar trend seen in placental weight (p = 0.03). Villous changes related to maternal malperfusion were more prevalent in the low and high BMI groups compared to middle-range BMI group (p < 0.01) and composite maternal vascular malperfusion lesions were also more prevalent in the groups of BMI extremities compared to the middle-range BMI group (p < 0.01).

CONCLUSION

Maternal BMI might influence neonatal outcomes and placental pathology in pregnancies complicated by preeclampsia. Both extremes of BMI were associated with higher rates of placental maternal vascular malperfusion. Balanced BMI in women at risk for preeclampsia may reduce the incidence of placental lesions.

Placental pathology in pregnancies with late fetal growth restriction and abnormal cerebroplacental ratio

INTRODUCTION

Late fetal growth restriction (FGR) is associated with mild growth restriction and normal or mild abnormal doppler flows. The cerebroplacental ratio (CPR) has been demonstrated as more sensitive to hypoxia than its individual components in these fetuses. We hypothesized that abnormal CPR in late FGR is reflected in specific placental vascular malperfusion lesions.

METHODS

Retrospective cohort study of late FGR newborns between 2012 and 2022 in a tertiary hospital. Overall, 361 cases were included: 104 with pathological CPR (study group), and 257 with normal doppler flows (control group). The primary outcome was a composite of maternal vascular malperfusion lesions (MVM) and fetal vascular malperfusion lesions (FVM). Secondary outcomes were macroscopic placental characteristics and various obstetrical and neonatal outcomes.

RESULTS

The study group had lower birthweight compared with the normal CPR group (2063.5 ± 470.5 vs. 2351.6 ± 387.4 g. P < 0.0001), higher rates of composite adverse neonatal outcomes (34.2% vs. 22.5%, p < 0.0001), lower mean placental weight (318 ± 71.6 vs. 356.6 ± 76.5 g, p < 0.0001), as well as a higher prevalence of Vascular lesions of MVM (15.3% vs. 5.0%, p = 0.002), villous lesions of FVM (37.5% vs. 24.9%, p = 0.02), and composite FVM lesions (36.5% vs. 25.6%, p = 0.04). On multivariate regression analysis for MVM lesions and composite FVM lesions, abnormal CPR was found as an independent risk factor (aOR 2.17, 95% CI 1.63-4.19, and aOR 1.31, 95% CI 1.09-3.97, respectively).

DISCUSSIONS

Abnormal CPR in late FGR is reflected in placental histopathologic vascular malperfusion lesions, and the incidence of these lesions is higher than in FGR placentas with normal CPR.

MiRNA-124a: a Potential Biomarker for Neurological Deficits Following Cardiac Surgery in Pediatric Patients

Brain injury is a major source of patient morbidity after cardiac surgery in children. New early accurate biomarkers are needed for the diagnosis of patients at risk for cerebral postoperative damage. Specific circulating miRNAs have been found as suitable biomarkers for many diseases. We tested whether miRNA-124a reflects neurological injury in pediatric patients following heart surgery. Serum samples were obtained from 34 patients before and six hours after heart surgery. MiRNAs-124a was quantified by RQ-PCR. MiRNA-124a levels six hours after heart surgery correlated with the neurological outcome of the patients. In children with neurological deficits, miRNA-124a levels increased while in those with no neurological deficits the levels decreased. MiRNA-124a was able, at six hours after the operation, to identify patients who are at risk for the appearance of neurological deficits. Circulating miRNA-124a is a potential biomarker for the appearance of neurological deficits in pediatric patients following heart surgery. Graphical Abstract.

Diastolic function as an early marker for systolic dysfunction and all-cause mortality among cancer patients

BACKGROUND

Increased survival among active cancer patients exposes a wide range of side effects, including cardiotoxicity, manifested by systolic dysfunction and associated with morbidity and mortality. Early diagnosis of subclinical function changes and cardiac damage is essential in the management of these patients. Diastolic dysfunction is considered common among cancer patients; however, its effect on systolic dysfunction or mortality is still unknown.

METHODS

Data were collected as part of the Israel Cardio-Oncology Registry, enrolling and prospectively following all patients evaluated in the cardio-oncology clinic in the Tel Aviv Sourasky Medical Center. All patients underwent echocardiographic examinations including evaluation of diastolic parameters and global longitudinal strain (GLS). Systolic dysfunction was defined as either an absolute reduction >10% in left ventricular ejection fraction to a value below 53% or GLS relative reduction >10% between the 1st and 3rd echocardiography examinations.

RESULTS

Overall, 190 active cancer patients were included, with a mean age of 58 ± 15 years and a female predominance (78%). During a median follow-up of 243 days (interquartile ranges [IQR]: 164-401 days), 62 (33%) patients developed systolic dysfunction. Over a median follow-up of 789 days (IQR: 521-968 days), 29 (15%) patients died. There were no significant differences in baseline cardiac risk factors between the groups. Using multivariate analysis, E/e' lateral and e' lateral emerged as significantly associated with systolic dysfunction development and all-cause mortality (P = .015).

CONCLUSION

Among active cancer patients, evaluation of diastolic function may provide an early marker for the development of systolic dysfunction, as well as all-cause mortality.

Cancer Therapeutics-Related Cardiac Dysfunction among Patients with Active Breast Cancer: A Cardio-Oncology Registry

BACKGROUND

Progress in the treatment of breast cancer has led to substantial improvement in survival, but at the cost of increased side effects, with cardiotoxicity being the most significant one. The commonly used definition is cancer therapeutics-related cardiac dysfunction (CTRCD), defined as a left ventricular ejection fraction reduction of > 10%, to a value below 53%. Recent studies have implied that the incidence of CTRCD among patients with breast cancer is decreasing due to lower doses of anthracyclines and low association to trastuzumab and pertuzumab treatment.

OBJECTIVES

To evaluate the prevalence of CTRCD among patients with active breast cancer and to identify significant associates for its development.

METHODS

Data were collected as part of the Israel Cardio-Oncology Registry, which enrolls all patients who are evaluated at the cardio-oncology clinic at our institution. Patients were divided to two groups: CTRCD and no-CTRCD.

RESULTS

Among 103 consecutive patients, five (5%) developed CTRCD. There were no significant differences in the baseline cardiac risk factors between the groups. Significant correlations of CTRCD included treatment with trastuzumab (P = 0.001) or pertuzumab (P < 0.001), lower baseline global longitudinal strain (GLS) (P = 0.016), increased left ventricular end systolic diameter (P < 0.001), and lower e' septal (P < 0.001).

CONCLUSIONS

CTRCD is an important concern among patients with active breast cancer, regardless of baseline risk factors, and is associated with trastuzumab and pertuzumab treatment. Early GLS evaluation may contribute to risk stratification and allow deployment of cardioprotective treatment.

Diastolic strain time as predictor for systolic dysfunction among patients with active breast cancer

BACKGROUND

Although diastolic dysfunction is common among patients treated with cancer therapy, no clear evidence has been shown that it predicts systolic dysfunction. This study evaluated the correlation of diastolic strain time (Dst) with the routine echocardiography diastolic parameters and estimated its role in the early detection of cardiotoxicity among patients with active breast cancer.

METHODS

Data were collected as part of the Israel Cardio-Oncology Registry (ICOR), a prospective registry enrolling all adult patients referred to the cardio-oncology clinic. All patients with breast cancer, planned for Doxorubicin therapy, were included. Echocardiography, including global longitudinal systolic strain (GLS) and Dst, was assessed at baseline before chemotherapy (T1), during Doxorubicin therapy (T2) and after the completion of Doxorubicin therapy (T3). Cardiotoxicity was determined by GLS relative reduction of ≥15%. Dst was assessed as the time measured (ms) of the myocardium lengthening during diastole.

RESULTS

Among 69 patients, 67 (97.1%) were females with a mean age of 52 ± 13 years. Dst was significantly associated with the routine diastolic parameters. Significant GLS reduction was observed in 10 (20%) patients at T3. Both in a univariate and a multivariate analyses, the change in Ds basal time from T1 to T2 emerged to be significantly associated with GLS reduction at T3 (P < .04).

CONCLUSIONS

Among breast cancer patients, Dst showed high correlation to the routine diastolic echocardiography parameters. Change in Ds basal time emerged associated with clinically significant systolic dysfunction as measured by GLS reduction.

The association of reduced global longitudinal strain with cancer therapy-related cardiac dysfunction among patients receiving cancer therapy

BACKGROUND

Cardiotoxicity is a leading cause of morbidity and mortality among patients receiving cancer therapy. The most commonly used definition is cancer therapy-related cardiac dysfunction (CTRCD) defined by a left ventricular ejection fraction reduction. Global longitudinal strain (GLS) has been implied to be superior in detecting early subclinical dysfunction.

OBJECTIVES

Evaluate the prevalence of reduced GLS and whether it is associated with CTRCD development among patients receiving cancer therapy.

METHODS

Data were collected as part of the Israel Cardio-Oncology Registry (ICOR), a prospective registry enrolling all adult patients receiving different types of cancer therapy, who were referred to the cardio-oncology clinic. Patients were divided into two groups-reduced GLS (> - 17%) vs. preserved GLS (≤ - 17%). Multivariable analyses were adjusted for a propensity score for baseline characteristics.

RESULTS

Among 291 consecutive patients, 48 (16%) patients were included in the reduced GLS group. Overall, 11 (5%) patients developed CTRCD at following echocardiogram evaluation. Patients with preserved GLS had a significantly lower risk for CTRCD development [odds ratio (OR) 0.11, 95% confidence interval (CI) 0.03-0.41, p = 0.001], with every 1-unit improvement of GLS the risk of CTRCD decreased by 16% (OR 0.84, 95%CI 0.73-0.95, p = 0.007). After adjustment for baseline characteristics, including cardiovascular risk factors and systolic function, preserved GLS remained significantly associated with a lower risk for CTRCD development (OR 0.11, 95%CI 0.02-0.64, p = 0.014), with every 1-unit improvement lowering the risk by 19% (OR 0.81, 95%CI 0.67-0.98, p = 0.032).

CONCLUSIONS

Reduced GLS is common among patients receiving cancer therapy and may identify patients at increased risk for CTRCD development.

Bilirubin Removal from an Hepatic Failure Patient by Resin Hemoperfusion

An hemoperfusion (HP) column, packed with beads of a macroreticular MR ion exchange resin which were made biocompatible by coating with a fine layer of cross-linked human albumin, was applied to the removal of bilirubin (BIL) from a jaundiced 69-year old man with hepatic failure.

The column was found most suitable for BIL removal. However, the high volumetric mass transfer coefficient of the unconjugated (UC) BIL indicates that this column could best be used for BIL removal from babies suffering from unconjugated hyperbilirubinemia.

Resin hemoperfusion for unconjugated bilirubin removal

The application of an anionic macroreticular ion exchange resin, coated with a thin cross-linked albumin layer, as a hemoperfusion device for the removal of unconjugated bilirubin from the blood of hyperbilirubinemic newborn babies is reviewed. In vivo hemoperfusion runs with hyperbilirubinemic animal models - either by a choledocho-suprarenal vein shunt or by direct infusion of bilirubin into the vein - showed that a 40-ml resin column can remove some 20 mg bilirubin in 3 h. Hemoperfusion of female 8-14 kg baboons showed no significant effect of the column on blood chemistry and coagulation factors and repeated runs had no ill effects.

Pulmonary angiotensin converting enzyme activity in elastase induced emphysema

Pulmonary emphysema would be expected to reduce angiotensin converting enzyme (ACE) activity due to diminished capillary bed. However, transpulmonary angiotensin conversion has been found to be unaffected or marginally reduced in emphysema. In the present study we examined the activity of ACE in an experimental model of emphysema. Vmax and Km of ACE were determined in lung homogenates of six hamsters with elastase-induced emphysema and seven control hamsters. In the emphysematous lungs, ACE activity was significantly elevated due to marked increase in Vmax (19.2 +/- 1.7 vs. 4.9 +/- 1.6 nmol/min/mg protein for emphysematous and control lungs, P < 0.01). The Km of ACE was unaffected by emphysema. We suggest that the increase in ACE activity may be an adaptive change to enable adequate metabolic activity in the face of progressive reduction in pulmonary capillary surface area in emphysema.

Transplacental transfer of ritodrine and its effect on placental glucose and oxygen consumption in an in vitro human placental cotyledon perfusion

Maternofetal transfer of ritodrine and its effect on placental glucose and oxygen consumption were studied using a recycling perfusion of maternal and fetal circulations of an isolated cotyledon of a term human placenta. 3H-labeled ritodrine was introduced into the maternal side of the perfusion system. Transfer was calculated from the linear rise of ritodrine concentrations on the fetal side and was found to be 7.31 +/- 1.02 ng/g placental wet weight/min (SEM) when 1.4 micrograms/ml of ritodrine was used (n = 3) and 14.7 +/- 1.06 ng/g placental wet weight/min when the concentration was 2.8 micrograms/ml (n = 5). The antipyrine transfer rate, 4.1 +/- 0.51 mg/kg/min (n = 8), was used to demonstrate perfusion adequacy and served as an internal standard. Upon computing the mass balance of ritodrine and antipyrine at the end of the experiment, it was found that 17% of ritodrine disappeared from the perfusion system compared to 0.7% of antipyrine (p less than 0.01). The introduction of ritodrine into the perfusion system did not affect placental glucose and oxygen consumption rates of 0.35 +/- 0.01 mumol/g/min (n = 7) and 0.19 +/- 0.013 mumol/g/min (n = 5), respectively.

Angiotensin-converting enzyme activity in the isolated perfused guinea pig lung

We have developed a pressure-dependent isolated lung perfusion system that can be used for the determination of pulmonary enzyme activity and kinetics under physiologic conditions. This development was done using two different artificial radiolabeled substrates, glycine-1-hippuryl-L-histidyl-L-leucine and phenyl-4(n)-hippuryl-glycyl-glycine, for the pulmonary enzyme, angiotensin-converting enzyme. With this system, we assessed the effects of different perfusate types upon the stability of the perfusion as well as the independent effects of pressure, flow, and substrate concentration on the activity of this enzyme. We concluded that this system enables the operator to determine the kinetics and activities of pulmonary enzymes independently of the effects of pressure and flow in a perfusion system that is stable for at least 3 h under physiologic conditions.

Does insulin affect placental glucose metabolism and transfer?

An in vitro recycled perfusion of the human placenta was used to investigate the effect of insulin on placental metabolism and transfer of glucose. Human insulin, 1000 microU/ml, was introduced into either maternal or maternal and fetal compartments. In one series of experiments placentas were used as either a control group or study group, whereas in the other series each placenta served as its own control. Metabolic effects were determined by measuring placental glucose and oxygen consumption and lactate production rate. The effect of insulin on transfer was studied by the use of 3-O-methylglucose labeled with tritium; this effect was expressed as the slope of maternal minus fetal concentrations on a natural logarithmic scale and compared with the antipyrine tagged with carbon 14. The stability of perfusate volume was used as an index for placental integrity, whereas absence of tissue edema demonstrated adequacy of perfusion. Neither of the metabolic parameters studied was significantly affected by insulin, and insulin did not have an effect on 3-O-methylglucose transfer rate. It was concluded that, in contrast to other tissues in the body, placental glucose metabolism and transfer are not sensitive to the action of insulin.

Renal bilirubin excretion in canine models of jaundice

Renal handling of bilirubin and its relationship to blood bilirubin level were investigated for up to 2 weeks in two models of jaundiced dogs, namely, chronic bile duct ligation (CBDL), which are mildly icteric, and choledococaval anastomosis (CDCA), which develop deep jaundice. The mean (+/- SD) urinary bilirubin excretion in CBDL plateaued at 30.3 +/- 9.3 mg/24 hr whereas in CDCA it continued to increase above the normal bilirubin production rate (56-84 mg/24 hr) up to 130-150 mg/24 hr. The renal clearance of bilirubin in both models was inversely proportional to serum bilirubin concentration. It was approximately twice as high in the CDCA model, which induced also a moderate diuresis. It is suggested that higher serum bilirubin levels in CDCA dogs is due to the increased production of bilirubin which is not compensated by the renal clearance of bilirubin.

Bilirubin removal from a jaundiced premature infant by resin hemoperfusion

To summarize the results: Bilirubin removal by hemoperfusion was successfully performed for the first time on a premature infant. The hemoperfusion caused no adverse effects on the clinical state of the infant. The bilirubin removed in 90 min--13 mg--indicates the existence of a large extravascular pool. Hemoperfusion is suggested for bilirubin removal from newborn babies, reducing the need for blood exchange with bank blood.

Serum bilirubin constituents in different experimental models of conjugated hyperbilirubinemia

The object of the study was to explain the differences in bilirubin level in various experimental jaundice models. The Bil constituents in conjugated hyperbilirubinemic dog models were identified. Total Bil was measured using the Jendrassik and Grof method and direct spectrophotometry. Conjugated and unconjugated Bil were measured using the Weber-Schalm extraction method. Bilirubin covalently bound to albumin was measured indirectly from the total Bil and the non-CBBA fraction. The non-CBBA was estimated either as the sum of the CB and UCB concentrations determined by the W-S method or as the nonprecipitated fraction after deproteinization with ammonium sulfate-saturated ethanol when using DS. The TB, CB, UCB, and CBBA levels were compared in two hyperbilirubinemic dog models: chronic bile duct ligation (CBDL) and internal choledochocaval anastomosis (CDCA). The mean TB in internal CDCA (16.5 +/- 3.67 mg%) was significantly higher than in CBDL (3.4 +/- 1.75 mg%). Most of the serum Bil in these two models was conjugated, 13.4 +/- 2.24 and 3.2 +/- 1.7 mg%, respectively. No CBBA was found in the CBDL or in the partially obstructed internal-CDCA dogs. The TB in an external-CDCA model was essentially similar to the internal-CDCA model. The indirect Bil level in the external-CDCA model was six to seven times higher than the UCB level, and the CBBA level varied between 30 and 80% of the TB. Up to 50% CBBA was found also in patients with intra- or extrahepatic cholestasis. The findings indicate that, unlike the commonly assumed hypothesis, the serum TB level in the CDCA models, which was higher than in the CBCL one, is not due to high UCB levels. Rather, hyperbilirubinemia in the external-CDCA model is due to increased levels of CBBA or, perhaps, to variations in the amount and/or composition of CB entering the blood and cleared by the kidney.

Tailor-made agarose-based reactive beads for hemoperfusion and plasma perfusion

Composite beads of approximately 1 mm diameter, made of crosslinked agarose and containing Fuller's Earth or zirconium oxide powders, were prepared and used in extracorporeal systems for blood detoxification. The former was used for the removal of Paraquat, while the latter was used to remove inorganic phosphate from hyperphosphatemic animals with or without acute renal failure. The high surface area of the powder, combined with the low resistance to diffusion in the crosslinked agarose matrix, are highly advantageous. The crosslinking provides high mechanical strength, heat stability, prolonged shelf life, good blood flow characteristics, and prevents the release of fine particles into the blood. Crosslinked agarose beads of 1 mm diameter, containing chemically-bound heparin were also prepared, and used as a model for direct contact removal of LDL-cholesterol from the blood of familial hypercholesterolemic patients by hemoperfusion. The high capacity of these beads (over 5 mg LDL/mL beads) indicates that this clinical modality can replace the highly expensive plasmapheresis procedure presently used.

Controlling anticoagulation in extracorporeal blood circuits (hemoperfusion)

The study demonstrates that different individuals (monkeys) need different heparin doses so as to avoid either clotting or bleeding when an extracorporeal blood system is involved. The linear correlation between PT and WBPTT values enables to utilize the latter for monitoring the heparin level in the blood. One procedure is based on the application of the Gotch and Keen intravenous heparinization model in its steady state limit by utilizing the pre-treatment evaluation of k/S, the ratio of the elimination rate constant to the individual's sensitivity to heparin. A second procedure involves the direct heparinization of the extracorporeal system. The heparin infusion rate is monitored through the arterial WBPTT values after relating the individual's PT or WBPTT values to the in vitro heparin concentration in the blood. In vitro and in vivo study of the effect of hemoperfusion through a column containing anion exchange particles on the amount and rate of heparin administration indicates that only the in vivo results are meaningful. The sharp response of WBPTT to relatively small changes of citrate concentration in the blood precludes individual monitoring by WBPTT. Work on the advantage of utilizing heparin together with citrate is required.

Controlling Anticoagulation in Extracorporeal Blood Circuits (hemoperfusion)

The study demonstrates that different individuals (monkeys) need different heparin doses so as to avoid either clotting or bleeding when an extracorporeal blood system is involved. The linear correlation between PT and WBPTT values enables to utilize the latter for monitoring the heparin level in the blood. One procedure is based on the application of the Gotch and Keen intravenous heparinization model in its steady state limit by utilizing the pre-treatment evaluation of k/S, the ratio of the elimination rate constant to the individual's sensitivity to heparin. A second procedure involves the direct heparinization of the extracorporeal system. The heparin infusion rate is monitored through the arterial WBPTT values after relating the individual's PT or WBPTT values to the in vitro heparin concentration in the blood.

In vitro and in vivo study of the effect of hemoperfusion through a column containing anion exchange particles on the amount and rate of heparin administration indicates that only the in vivo results are meaningful. The sharp response of WBPTT to relatively small changes of citrate concentration in the blood precludes individual monitoring by WBPTT. Work on the advantage of utilizing heparin together with citrate is required.

Preparation of a biocompatible albumin-coated ion exchange resin for bilirubin removal from the blood of jaundiced newborns

Removal of bilirubin by hemoperfusion with ion exchange resin particles is suggested to replace exchange transfusion of blood of jaundiced infants in some cases of unconjugated hyperbilirubinemia. The hemoperfusion system developed here consists of a packed bed of a macroreticular resin which is made biocompatible by a coating of a monomolecular layer of albumin. The choice of the appropriate ionic form of the resin and the proper albumin coating and crosslinking procedure assures a high bilirubin adsorption capacity and excellent blood compatibility of the resin. The albumin coated resin removes in vitro 80-90% of the bilirubin initially present in the plasma. The results encourage in vivo clinical studies.

Bilirubin removal from an hepatic failure patient by resin hemoperfusion

An hemoperfusion (HP) column, packed with beads of a macroreticular MR ion exchange resin which were made biocompatible by coating with a fine layer of cross-linked human albumin, was applied to the removal of bilirubin (BIL) from a jaundiced 69-year old man with hepatic failure. The column was found most suitable for BIL removal. However, the high volumetric mass transfer coefficient of the unconjugated (UC) BIL indicates that this column could best be used for BIL removal from babies suffering from unconjugated hyperbilirubinemia.