Fall In Hematocrit Research Articles

Invited Commentary

Does the likeness in means and ranges of hemoglobin (Hgb) from birds to mammals suggest that this physiological equilibrium has emerged more than once by natural selection? Is it by chance that the “ideal hematocrit” across the animal kingdom, when plotted against viscosity, usually follows a similar concave curve, peaking around a value of 40? Are events that evolved to maximize survival and reproductive fitness hundreds of millions of years ago relevant to perioperative management of patients? And should the anemia of a child with a moderately sized ventricular septal defect be corrected to avoid surgery? Cholette and colleagues [1Cholette J.M. Swartz M.F. Rubenstein J. et al.Outcomes using a conservative versus liberal red blood cell transfusion strategy in infants requiring cardiac operation.Ann Thorac Surg. 2017; 103: 206-215Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar] do not address these questions. I congratulate them, however, for their perseverance (this is a follow-up study) and for completing likely a difficult study. Further, they clearly show that one can avoid red blood cell (RBC) transfusion in most children after biventricular repair and in a reasonable fraction of those palliated with cavopulmonary or systemic-to-pulmonary artery shunting. They randomized 134 patients after biventricular and 57 patients after palliative surgery (including 12 s/p Norwood), to either a “restrictive” (Hgb of 7.0) or “liberal” (Hgb of 9.0 g/dL) threshold for transfusion. They report similar lactate, avO2 differences, and clinical results between the two groups and, therefore, infer that clinical judgment should guide transfusion decisions. But whose judgment? Once a critical care colleague said that just because you can stand in a canoe in the middle of the lake, it does not mean you should. Therefore, without specific guidelines, one is left with the judgment of one clinician versus another. Most would agree that RBC transfusions are not without risk; for example, many have shown the associated increased risk of infection. The typical reason (tachycardia, low blood pressure, low urine output, low mixed venous saturations) for treating anemia are practical starting points, but some patients have much less reserve than others do, and clinical circumstances may mask or decrease the potential for applicability of such features. The baby with pulmonary atresia/intact ventricular septum and RV dependent coronary circulation and coronary atresia may not tolerate heart rates in the 150s or 160s, let alone the 170s or 180s. Lactate, as used by the authors, is a late marker of tissue hypoxia, only to rise with anaerobic glycolysis. Other notable findings from the study include the difference in transfusion rates between the two groups: one transfusion. Authors provide no information on number of laboratory tests, which is perhaps the primary driving force for blood loss after surgery (all patients started with same baseline Hgb). It is tempting to speculate that the restrictive approach perhaps influenced the perioperative management. If true, adopting a restrictive strategy would be a laudable goal in lessening the number of such tests. It is also notable that 4 of the 6 babies for whom the restrictive strategy was violated were newborns who had undergone one form or another of arch reconstruction. Over 80 years ago, Robin Fahraeus remarked on the fall of hematocrit in blood flowing through smaller-caliber tubes. Future observations confirmed the differential segregation of RBCs and plasma in divisions of microvasculature, whether by default or because of vasoactive agents. These observations and other experiments of nature (e.g., the Antarctic Icefish compensates for no Hgb by having a much larger heart, high stroke volume, and dense capillary network) highlight that while an arbitrary Hgb value is not a signal for transfusion, great caution should be exercised when deciding whether a patient should or should not receive a transfusion. The decision not to transfuse could be just as dangerous as the one to transfuse. Outcomes Using a Conservative Versus Liberal Red Blood Cell Transfusion Strategy in Infants Requiring Cardiac OperationThe Annals of Thoracic SurgeryVol. 103Issue 1PreviewThe optimal hemoglobin for infants after cardiac operation is unknown. Red blood cells (RBCs) are commonly transfused to maintain high hemoglobin concentrations in the absence of a clinical indication. We hypothesized that infants can be managed with a postoperative conservative RBC transfusion strategy, resulting in lower daily hemoglobin concentrations, without evidence of impaired oxygen delivery (ie, lactate, arteriovenous oxygen difference [avO2diff]), or adverse clinical outcomes. Full-Text PDF

Therapeutic efficacy and effects of artesunate-amodiaquine and artemether-lumefantrine on malaria-associated anaemia in Nigerian children aged two years and under.

BackgroundArtemisinin-based combination therapies are recommended as first-line treatments for uncomplicated falciparum malaria, but there is little evaluation of their efficacy and effects on uncomplicated malaria-associated anaemia in children aged 2 years and under.MethodsParasitological efficacy and effects on malaria-associated anaemia were evaluated in 250 malarious children aged 2 years and under, and efficacy was evaluated in 603 malarious children older than two but younger than 5 years of age following treatment with artesunate-amodiaquine (AA) or artemether-lumefantrine (AL). Kinetics of the disposition of parasitaemia following treatment were evaluated using a non-compartment model. Late-appearing anaemia (LAA) was diagnosed using the following criteria: clearance of parasitaemia, fever and other symptoms occurring within 7 days of starting treatment, adequate clinical and parasitological response on days 28–42, haematocrit (HCT) ≥ 30 % at 1 and/or 2 weeks, a fall in HCT to < 30 % occurring at 3–6 weeks, absence of concomitant illness at 1–6 weeks, and absence of asexual parasitaemia detected using both microscopy and polymerase chain reaction (PCR) at 1–6 weeks.ResultsOverall, in children aged 2 years and under, the PCR-corrected parasitological efficacy was 97.2 % (95 % CI 92.8–101.6), which was similar for both treatments. In children older than 2 years, parasitological efficacy was also similar for both treatments, but parasite prevalence 1 day after treatment began was significantly higher, and fever and parasite clearance times were significantly faster in the AA-treated children compared with the AL-treated children. Declines in parasitaemia were monoexponential with an estimated elimination half-time of 1 h. Elimination half-times were similar for both treatments. In children aged 2 years and under who were anaemic at presentation, the mean anaemia recovery time was 12.1 days (95 % CI 10.6–13.6, n = 127), which was similar for both treatments. Relatively asymptomatic LAA occurred in 11 children (4.4 %) aged 2 years and under, the recovery from which was uneventful.ConclusionThis study showed that AA and AL are efficacious treatments for uncomplicated falciparum malaria in Nigerian children aged 2 years and under, and that AA clears parasitaemia and fever significantly faster than AL in children older than 2 years. Both treatments may cause a relatively asymptomatic LAA with uneventful recovery in a small proportion of children aged 2 years and under.Trials registrationPan African Clinical Trial Registry PACTR201508001188143, 3 July 2015; PACTR201510001189370, 3 July 2015; PACTR201508001191898, 7 July 2015 and PACTR201508001193368, 8 July 2015 http://www.pactr.org.Electronic supplementary materialThe online version of this article (doi:10.1186/s40249-016-0165-2) contains supplementary material, which is available to authorized users.

Tranexamic Acid Administration in Total Knee Arthroplasty Without Tourniquet

Objective:There are multiple documented advantages of undertaking total knee arthroplasty (TKA) without tourniquet, however, increased rates of blood loss and transfusion are often cited as contraindications to this approach. The aim of this study was to examine the effect of intra-operative TA administration on blood loss and transfusion rates in TKA without pneumatic tourniquet, using Rivaroxaban as thrombo-embolic prophylaxis.Method:120 patients split into two continuous data sets, (A+B), underwent TKA without application of above knee tourniquet, receiving a post-operative dose of oral Rivaroxaban within 8 hours. Group B patients received an intra-operative dose of 1 gram of Tranexamic Acid intravenously before the first cut, whilst those in group A did not. Haemoglobin and Haematocrit levels were recorded peri-operatively. A revised Gross formula was used to calculate blood loss. Four patients were excluded from the study for incomplete data.Result:58 patients (M34F24) in Group A, average age 6, had a mean Haemoglobin drop of 33gram/litre, Haematocrit drop of 0.097litre/litre (9.7%), with an average calculated blood loss of 1393 ml. 58 (M34, F24) patients in group B, average age 67, had a Haemoglobin drop of 25.2gram/litre, Haematocrit drop of 0.076litre/litre (7.6%) with an average calculated blood loss of1079 ml. Thus Group A patients were seen to sustain significantly more blood loss without TA administration, with a 29.1% larger calculated blood loss, a 25.5% larger drop in Haemoglobin and a 27.6% larger fall in Haematocrit. Transfusion rate was 5.2%(3 patients) per group.Conclusion:TA was shown to be effective in reducing blood loss in TKA without tourniquet using Rivaroxaban. Transfusion rates of 5.2% across both groups is close to 1/10th of the transfusion rate reported for major studies of TKA using Rivaroxaban with tourniquet application, and 1/8th of the transfusion rate in studies of TKA with administration of TA and use of tourniquet.

Iatrogenic iliac arteriovenous fistula with aortic pseudoaneurysm formation post lumbar (L4-L5) laminectomy and pedicular screw fixation.

Nowadays lumbar laminectomy is a common surgery in daily practice and a very safe procedure, but it can result in sudden life threatening though infrequent vascular complications with greater than 50% mortality [1]. Such events usually require immediate intervention, so it is essential that anesthesiologists and surgeons be aware of this potential complication, its manifestation and treatment. The incidence of iatrogenic vascular complications in lumbar spine surgery is reported to be 0.01%-0.17% [1]. Although reported cases are few, unrecognised events are more than expected. However when one such event does occur, it can cause fatality in an otherwise healthy patient. We present a case of a 55-years-old male, American Society of Anesthesiologists physical status I with low backache since 10 years, underwent laminectomy and screw fixation for the same. On the ninth postoperative day he started developing right lower limb swelling associated with pain. Deep vein thrombosis was ruled out on venous doppler. On postoperative day 15, he started developing dyspnea, and generalized edema. Abdominal bruit was present and neck veins were engorged. On postoperative day 16, facial edema increased and hypotension developed. CT angiogram of chest and abdomen revealed distal right common iliac artery fistulous communication with common iliac vein with prominent inferior vena cava and hepatic vein, pseudo-aneurysm arising from site of fistula (4.2 × 3.8 × 3.1 cc), neck of aneurysm measuring 18.5 mm (Fig. 1). CT chest showed bilateral pleural effusion with ground glass opacities. Emergency aneurysm repair was done on the same day. Postoperatively he was shifted to the surgical intensive care unit for elective ventilation and monitoring due to massive fluid shifts intra-operatively and massive hemorrhage. He was later hemodynamically stable and kept in intensive care unit for 3 more days and subsequently shifted to ward on postoperative day 4. Further course in ward was uneventful and the patient was discharged on postoperative day 7. Fig. 1 (A) Three dimensional computerized tomography reconstruction shows right common iliac arteriovenous fistula with pseudoaneurysm (Arrow). (B) Computerized tomography Angiogram shows a right common iliac arteriovenous fistula with pseudo-aneurysm (Arrow). ... The L4-5 disc space is the most common site for a herniation of intervertebral disc [2]. Bifurcation of the aorta and inferior vena cava lies just anterior to this disc space, separated from it only by the anterior spinal ligament. The pathogenesis of iatrogenic vascular injury after spinal injury relates to the anatomical complexity of the aortic bifurcation and inferior vena cava confluence occurring at or below L4. They may present immediately in the intraoperative period or remain subclinical for days to years [3]. Bleeding from the wound is not a reliable sign as the self-sealing effect of the anterior annulus fibrosus and anterior longitudinal ligament may prevent any bleeding to be seen posteriorly. These tissues are tough and elastic, leading to blood leakage in the retroperitoneal space rather than the operating field. Signs and symptoms are equally wide ranging and include intra-operative and postoperative hypotension, associated fall in hematocrit, acute ischemia, distal pulse deficit, bruit, thrill, pulsatile abdominal mass, abdominal pain, expanding hematoma, limb edema and non-healing wounds. As the arterial injury drain directly into the low pressure venous system, hemorrhage is an uncommon presentation with arteriovenous fistula and hence it becomes very difficult to identify such injuries. An arteriovenous fistula should be suspected in a patient with a history of lower lumbar disc surgery followed by progressive swelling of a lower limb and associated bruit [4]. Thus, a high index of suspicion is needed amongst anesthesiologists given the rarity of complications and wide range of presentations.

Assessment of Blood Loss in Abdominal Myomectomy by Intramyometrial Vasopressin Administration Versus Conventional Tourniquet Application.

Myomectomy is an invasive surgical procedure. It can be associated with intraoperative and postoperative complications like excessive haemorrhage. There are various methods to control haemorrhage like pharmacological and as well as mechanical methods. This study was taken to compare intraoperative blood loss following abdominal myomectomy after receiving intramyometrial vasopressin or tourniquet application and to estimate postoperative reduction in haemoglobin & haematocrit values. The study was a randomised single blinded parallel group study. Total 48 patients were included in this study according to inclusion and exclusion criteria. All patients were divided into two groups i.e. 'T' and 'V' group, 24 in each group. 'T' group received conventional tourniquet application and 'V' group received intramyometrial vasopressin administration. The analyses in this study were both sided and p<0.05 was considered significant statistically. The Software used were Statistica version 6 (Tulsa, Oklahoma: Stat Soft Inc., 2001) and Graph Pad Prism version 5 (San Diego, California: Graph Pad Software Inc., 2007). The blood loss in the tourniquet group was significantly higher (p=<0.001). Postoperative haemoglobin and haematocrit were lower in tourniquet group than vasopressin group. There was significant fall in haemoglobin and haematocrit in postoperative period in both group (p=<0.001) but it was more in tourniquet group. Total five patients (three in tourniquet group and two in vasopressin group) had received one unit whole blood transfusion. Intramyometrial vasopressin injection during myomectomy operation more effectively decreases the blood loss, need for blood transfusion and it causes less reduction in haemoglobin and haematocrit. Thereby it seems to be an effective method without having any risk of ischemic damage to the uterus.

Temporal changes in haematocrit following artemisinin-based combination treatments of uncomplicated falciparum malaria in children.

BackgroundArtemisinin-based combination treatments (ACTs) or intravenous artesunate are used in over 100 countries for uncomplicated or severe falciparum malaria. Although intravenous artesunate may cause delayed haemolytic anaemia, there is little evaluation of the temporal changes in haematocrit following ACTs.MethodsClinical and parasitological parameters were measured before and following treatment of uncomplicated falciparum malaria in children with artesunate-amodiaquine (AA) or artemether-lumefantrine (AL) over 6-weeks. Changes in haematocrit were characterized in individual patients based on a haematocrit <30 % or ≥30 % before and following treatment. Kinetics of the deficit in haematocrit from <30 % until attainment of ≥30 % were estimated by a non-compartment model.ResultsIn 248 of 1180 children eligible for evaluation, common temporal patterns were: no change or increase in haematocrit from ≥ 30 % [50 % of patients], haematocrit >30 % at presentation declining to <30 % within 2 weeks (early monophasic fall) [19 % of patients], and haematocrit <30 % at presentation increasing to ≥ 30 % [23 % of patients]. Haematocrit >30 % at presentation declining to <30 %, 3–5 weeks later (late monophasic fall) occurred in 7 children (3 %). Fall in haematocrit ≥5 units following treatment occurred in 57 children [23 %] between 14 and 28 days after treatment began. Baseline parasitaemia and proportion with > 100,000μL-1 asexual forms were significantly higher in children with ≥5 units compared to <5 units fall in haematocrit 21 or 28 days after treatment began. Irrespective of pattern, declines in haematocrit deficit from <30 % were mono-exponential, with similar half-times for AA- and AL-treated children (1.32 d versus 1.14 d). Anaemia half-time correlated significantly positively with anaemia recovery time in the same patients (r = 0.55, P < 0.0001). Bland-Altman analysis of 9 or 10 multiples of anaemia half-time and anaemia recovery times showed narrow limit of agreement with insignificant biases (P = 0.19 or 0.63, respectively).ConclusionsIn uncomplicated falciparum malaria, increases or falls in haematocrit are common following ACTs. Falls in haematocrit ≥ 5 units are common and may or may not result in early or late anaemia. In children who recovered from acute falciparum malaria-associated anaemia following ACTs, decline in haematocrit deficit is mono-exponential.Trials registrationPan African Clinical Trial Registry PACTR201508001188143, 3 July 2015; PACTR201508001191898, 7 July 2015 http://www.pactr.org.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-1219-y) contains supplementary material, which is available to authorized users.

Suppression of erythropoiesis by dietary nitrate.

In mammals, hypoxia-triggered erythropoietin release increases red blood cell mass to meet tissue oxygen demands. Using male Wistar rats, we unmask a previously unrecognized regulatory pathway of erythropoiesis involving suppressor control by the NO metabolite and ubiquitous dietary component nitrate. We find that circulating hemoglobin levels are modulated by nitrate at concentrations achievable by dietary intervention under normoxic and hypoxic conditions; a moderate dose of nitrate administered via the drinking water (7 mg NaNO3/kg body weight/d) lowered hemoglobin concentration and hematocrit after 6 d compared with nonsupplemented/NaCl-supplemented controls. The underlying mechanism is suppression of hepatic erythropoietin expression associated with the downregulation of tissue hypoxia markers, suggesting increased pO2. At higher nitrate doses, however, a partial reversal of this effect occurred; this was accompanied by increased renal erythropoietin expression and stabilization of hypoxia-inducible factors, likely brought about by the relative anemia. Thus, hepatic and renal hypoxia-sensing pathways act in concert to modulate hemoglobin in response to nitrate, converging at an optimal minimal hemoglobin concentration appropriate to the environmental/physiologic situation. Suppression of hepatic erythropoietin expression by nitrate may thus act to decrease blood viscosity while matching oxygen supply to demand, whereas renal oxygen sensing could act as a brake, averting a potentially detrimental fall in hematocrit.—Ashmore, T., Fernandez, B. O., Evans, C. E., Huang, Y., Branco-Price, C., Griffin, J. L., Johnson, R. S., Feelisch, M., Murray, A. J. Suppression of erythropoiesis by dietary nitrate.

Fall in Hematocrit per 1000 Parasites Cleared From Peripheral Blood

A simple method to estimate antimalarial drug-related fall in hematocrit (FIH) after treatment of Plasmodium falciparum infections in the field is described. The method involves numeric estimation of the relative difference in hematocrit at baseline (pretreatment) and the first 1 or 2 days after treatment begun as numerator and the corresponding relative difference in parasitemia as the denominator, and expressing it per 1000 parasites cleared from peripheral blood. Using the method showed that FIH/1000 parasites cleared from peripheral blood (cpb) at 24 or 48 hours were similar in artemether-lumefantrine and artesunate-amodiaquine-treated children (0.09; 95% confidence interval, 0.052-0.138 vs 0.10; 95% confidence interval, 0.069-0.139%; P = 0.75) FIH/1000 parasites cpb in patients with higher parasitemias were significantly (P < 0.0001) and five- to 10-fold lower than in patients with lower parasitemias suggesting conservation of hematocrit or red cells in patients with higher parasitemias treated with artesunate-amodiaquine or artemether-lumefantrine. FIH/1000 parasites cpb were similar in anemic and nonanemic children. Estimation of FIH/1000 parasites cpb is simple, allows estimation of relatively conserved hematocrit during treatment, and can be used in both observational studies and clinical trials involving antimalarial drugs.

Localized pericardial tamponade: Does it always need exploration?

A 48-year-old female patient underwent coronary artery bypass surgery. One-hour after surgery, the patient developed hemodynamic instability. Transthoracic echocardiography (TTE) was inconclusive. Transesophageal echocardiography (TEE) was performed and it revealed localised collection around right atrium. In spite of the evidence of localized tamponade, wait and watch policy was employed rather than re-exploring the patient emergently. The patient recovered uneventfully. If hemodynamics remain stable and there is no fall in hematocrit and no increase in effusion on TEE/TTE examination, then localized tamponade can be managed conservatively without reexploring the patient.

Direct Fetal Intravenous Immunoglobulin Infusion as an Adjunct to Intrauterine Fetal Blood Transfusion in Rhesus-Allommunized Pregnancies: A Pilot Study

Objectives: To study the usefulness of direct fetal intravenous immunoglobulin (IVIG) infusion along with intrauterine transfusion (IUT) in the management of severe fetal anemia in rhesus (Rh) alloimmunized pregnancies. Methods: Thirty-four consecutive Rh-isoimmunized pregnant women who required serial IUTs received either blood alone (control group, n = 16) or IVIG and blood (study group, n = 18). Pregnancies were followed up to delivery, and fetal outcome was recorded. The rate of fall of hematocrit was measured and compared between the two groups. Results: There was a slower rate of fall of hematocrit in the study group (IUT and IVIG) compared to the control group (only IUT). The mean rate of fall was 0.72 ± 0.54% per day in the study group while it was 1.29 ± 0.95% per day in the control group (p = 0.005). Conclusion: Fall of fetal hematocrit was reduced in the study group. The results of this pilot study can be used to time the next transfusion in patients receiving IVIG along with IUT (taking the rate of fall as 0.70%). This may eventually result in decreasing the number of transfusions per fetus.

Antegrade rapid prime displacement in elective coronary artery surgery is associated with lower perioperative blood transfusions and a shorter hospital stay

Haemodilution during cardiopulmonary bypass is associated with increased perioperative blood transfusions and is thought to reduce intraoperative oxygen delivery to the brain. We sought to evaluate our method of rapid antegrade prime displacement in the context of the perioperative blood transfusion rate, intraoperative cerebral saturations and postoperative hospital stay. Retrospective analysis of 160 propensity-matched patients undergoing elective coronary artery bypass grafting was performed comparing different perfusion strategies on perioperative blood transfusion and length of postoperative stay. Eighty patients who had rapid antegrade prime displacement and vacuum-assisted venous drainage (RAD-VAD) were compared with 80 patients who had conventional cardiopulmonary bypass with gravity drainage (CB). RAD-VAD involved displacing all or most of the prime in the circuit with the patient's own blood prior to the initiation of cardiopulmonary bypass within a 15-20 s window. Within each group, 10 patients had intraoperative cerebral saturation measurements. There were no differences in the baseline characteristics between the groups. Both groups had a significant fall (P < 0.05) in haematocrit during cardiopulmonary bypass from preoperative values, however, the fall in haematocrit was significantly less in the RAD-VAD group (P < 0.05). There was significantly (P < 0.05) less intraoperative and postoperative homologous blood transfusions in the RAD-VAD group (47.892 ml ± 8.14 and 76.58 ml ± 21.58) compared with the CB group (229.06 ml ± 105.03 and 199.91 ml ± 47.13). There was a significant fall in cerebral saturations within both groups (P < 0.05) but it was not significant between the groups. The postoperative stay was significantly (P < 0.05) shorter in the RAD-VAD group compared with the conventional group (7.74 days ± 0.51 vs 10.13 days ± 0.95). RAD-VAD is associated with a significantly lower blood transfusion rate perioperatively and shorter hospital stays compared with CB.

Excessive Fluoride Consumption Leads to Accelerated Death of Erythrocytes and Anemia in Rats

The present study was performed to evaluate an overall effect of long-term consumption of excessive fluoride (F) amounts by rats on their erythrocytes. The animals were administered regular drinking water (0.4ppm F) or the same water supplemented with 2, 10, and 20ppm F (as NaF) for 12months. Chronic exposure of the rats to increasing F doses induced a progressive rise of the plasma F concentration accompanied by a dose-dependent fall of hematocrit and decrease in the mean erythrocyte volume. Consumption of 10 and 20ppm F resulted in appearance of morphologically abnormal cells (stomatocytes and echinocytes) in the peripheral blood. Rise of the water F concentration to 20ppm F led to significant increase in the number of phosphatidylserine-exposing erythrocytes, although suppression of cell viability was revealed in all three groups of F-poisoned rats. A compensatory enhanced release of reticulocytes was not sufficient to compensate for erythrocyte loss. Dose-dependent accumulation of free cytosolic Ca(2+) appears to be a major pathophysiological process underlying the development of F-induced death processes in rat erythrocytes. In addition, 10 and 20ppm F induced ATP depletion and generation of peroxides in erythrocytes, whereas superoxide and glutathione levels were not altered. Thus, long-term intoxication of the rats with F triggers premature death of their erythrocytes due to intrinsic death-associated biochemical defects and development of anemia.

Misoprostol to reduce intraoperative and postoperative hemorrhage during cesarean delivery: a systematic review and metaanalysis

To evaluate the efficacy and safety of prophylactic misoprostol use at cesarean delivery for reducing intraoperative and postoperative hemorrhage. Systematic review and metaanalysis of randomized controlled trials. Seventeen studies (3174 women) were included of which 7 evaluated misoprostol vs oxytocin and 8 evaluated misoprostol plus oxytocin vs oxytocin alone. Overall, there were no significant differences in intraoperative and postoperative hemorrhage between sublingual or oral misoprostol and oxytocin. Rectal misoprostol, compared with oxytocin, was associated with a significant reduction in intraoperative and postoperative hemorrhage. The combined use of sublingual misoprostol and oxytocin, compared with the use of oxytocin alone, was associated with a significant reduction in the mean decrease in hematocrit (mean difference, -2.1%; 95% confidence interval, -3.4 to -0.8) and use of additional uterotonic agents (relative risk, 0.33; 95% confidence interval, 0.18-0.62). Compared with oxytocin alone, buccal misoprostol plus oxytocin reduced the use of additional uterotonic agents; rectal misoprostol plus oxytocin decreased intraoperative and postoperative blood loss, mean fall in hematocrit, and use of additional uterotonic agents; and intrauterine misoprostol plus oxytocin reduced the mean fall in hemoglobin and hematocrit. Women receiving misoprostol, alone or combined with oxytocin, had a higher risk of shivering and pyrexia. Misoprostol combined with oxytocin appears to be more effective than oxytocin alone in reducing intraoperative and postoperative hemorrhage during cesarean section. There were no significant differences in intraoperative and postoperative hemorrhage when misoprostol was compared to oxytocin. However, these findings were based on a few trials with methodological limitations.

Disruption of the endothelin A receptor in the nephron causes mild fluid volume expansion

BackgroundEndothelin, via endothelin A receptors (ETA), exerts multiple pathologic effects that contribute to disease pathogenesis throughout the body. ETA antagonists ameliorate many experimental diseases and have been extensively utilized in clinical trials. The utility of ETA blockers has been greatly limited, however, by fluid retention, sometimes leading to heart failure or death. To begin to examine this issue, the effect of genetic disruption of ETA in the nephron on blood pressure and salt handling was determined.MethodsMice were generated with doxycycline-inducible nephron-specific ETA deletion using Pax8-rtTA and LC-1 transgenes on the background of homozygous loxP-flanked ETA alleles. Arterial pressure, Na metabolism and measures of body fluid volume status (hematocrit and impedance plethysmography) were assessed.ResultsAbsence of nephron ETA did not alter arterial pressure whether mice were ingesting a normal or high Na diet. Nephron ETA disruption did not detectably affect 24 hr Na excretion or urine volume regardless of Na intake. However, mice with nephron ETA knockout that were fed a high Na diet had mild fluid retention as evidenced by an increase in body weight and a fall in hematocrit.ConclusionsGenetic deletion of nephron ETA causes very modest fluid retention that does not alter arterial pressure. Nephron ETA, under normal conditions, likely do not play a major role in regulation of Na excretion or systemic hemodynamics.

Experience of open renal trauma in a urology service

IntroductionOpened renal trauma in urban areas reaches 15–20% of all renal traumas. It is mainly caused by gunshot wounds or knives. Gunshot wounds are classified as high energy trauma and are usually associated with other organ injuries. We present our experience in opened renal trauma in the last 24 months. Material and methodsRetrospective study: patients with thoracic, abdominal and thoracoabdominal trauma admitted to the emergency room between July 2009 and June 2011 were studied. Fourteen patients were identified with opened renal trauma, with diagnostic confirmation by imaging study or during surgery. ResultsAge ranged from 16 to 37 years, with a mean age of 24.5 years. Thirteen patients were male. The mechanism of injury was produced by gunshot in 71% (10/14) and by knife in 29% (4/14). The opened renal traumas were classified according to the American Association for the Surgery of Trauma. Of these, 3/14 (21%) belonged to grade II, 4/14 (29%) to grade III, 4/14 (29%) to grade IV and 3/14 to grade V (21%). Fall in hematocrit ranged from 1% to 27%, with an average of 13.9%. Expectant management was done in six patients, however, this management did not take into account those surgeries performed due to non-urologic organ injuries. Six patients (42%) required nephrectomy. Thoraco-abdominal injuries were associated in 11 patients (79%). ConclusionsDespite the low incidence of opened renal trauma, many patients are observed when other national reports are considered, probably due to the socio-cultural characteristics of this hospital.

Oral tranexamic acid reduces blood loss in total knee replacement arthroplasty

Background Tranexamic acid is a potent antifibrinolytic, which has shown efficacy in reducing blood loss in total knee arthroplasty when administered intravenously. We performed a double-blind randomized controlled trial of oral tranexamic acid in total knee arthroplasty to assess the blood sparing effect of this preparation. We asked whether the oral formulation of tranexamic acid had significant benefit in the prevention of blood loss in total knee replacement arthroplasty. Methods Forty-six patients undergoing unilateral total knee replacement arthroplasty for osteoarthritis were randomized to a treatment or control group (26 active tranexamic acid and 20 placebo). The treatment arm received three doses of 1500 mg encapsulated oral tranexamic acid at 8-hour intervals preoperatively, with the third dose occurring within 2 hours of surgery, and a fourth dose 6 hours postoperatively. The control arm received an identically encapsulated nonactive formulation at the same dosing intervals. Outcome measures were hemoglobin and hematocrit taken 24 hours postoperatively and total blood loss in wound drains at 24 hours. A record was made of any transfusion events occurring in either group as well as any thromboembolic complications. A follow-up phone call at 3 months was made to identify any late thromboembolic events. Results There was a significant reduction in blood drained at 24 hours (248 mL; P=0.34) as well as a significant decrease in the fall of both hemoglobin (P=0.02) and hematocrit (P=0.03) within the tranexamic acid group. No significant difference in transfusion events was found. Only one case of deep venous thrombosis occurred, and this was in the placebo group. Conclusions Our study showed that oral tranexamic acid is efficacious as a blood sparing medication in total knee replacement arthroplasty and appears to be safe in a selected population. Level of Evidence Therapeutic level 1.

Experiencia de traumatismo renal abierto en un Servicio de Urología

IntroductionOpened renal trauma in urban areas reaches 15 to 20% of all renal traumas. It is mainly caused by gunshot wounds or knifes. Gunshot wounds are classified as high energy trauma and are usually associated to other organ injuries. We present our experience in opened renal trauma in the last 24 months. Material and methodsRetrospective study: patients with thoracic, abdominal and thoraco-abdominal trauma admitted to the emergency room between July 2009 and June 2011 were studied. Fourteen patients were identified with opened renal trauma, with diagnostic confirmation by imaging study or during surgery. ResultsAges ranged from 16 to 37 years, with a mean age of 24.5 years. Thirteen patients were males. The mechanism of injury was produced by gunshot in 71% (10/14) and by knife in 29% (4/14). The opened renal traumas were classified according to the American Association for the Surgery of Trauma. Of these, 3/14 (21%) belonged to grade II, 4/14 (29%) to grade III, 4/14 (29%) to grade IV and 3/14 to grade V (21%). Fall in hematocrit ranged from 1% to 27%, with an average of 13.9%. Expectant management was done in six patients, however, this management did not take into account those surgeries performed due to non-urologic organ injuries. Six patients (42%) required nephrectomy. Thoraco-abdominal injuries were associated in 11 patients (79%). ConclusionsDespite the low incidence of opened renal trauma, many patients are observed when other national reports are considered, probably due to the socio-cultural characteristics of this hospital.

Haematoma Caused by Bone Marrow Aspiration and Trephine Biopsy

We report a case of a bone marrow aspiration and trephine biopsy (BMATB) associated haematoma in an 85-years old male without any predisposing risk factors. Six days after BMATB, he suffered from a massive thigh and buttock haematoma and a fall in haematocrit. It is important to know that BMATB can have complications aiding early recognition and therapy.

A Simple Dose Regimen of Artesunate and Amodiaquine Based on Arm Span- or Age Range for Childhood Falciparum Malaria: A Preliminary Evaluation

A dose regimen of artesunate and amodiaquine based on arm span- or age range (DRAAAS), derived from a study of 1674 children, was compared with standard dose regimen of the same drugs calculated according to body weight (SDRAA) in 68 malarious children. Children on DRAAAS received 0.8-1.0 of artesunate/kg and 0.9-1.2 times amodiaquine/kg compared with those receiving SDRAA. Parasite and fever clearance and fall in hematocrit in the first 3 days were similar; both regimens were well tolerated. DRAAAS is simple and is efficacious.

Therapeutic efficacy and effects of artemether-lumefantrine and artesunate-amodiaquine coformulated or copackaged on malaria-associated anemia in children with uncomplicated Plasmodium falciparum malaria in Southwest Nigeria.

The therapeutic efficacy and effects of artemether-lumefantrine (AL) and artesunate-amodiaquine co-formulated (AAcf) or co-packaged (AAcp) on malaria-associated anemia (MAA) were evaluated in 285 children < 12 years of age with uncomplicated Plasmodium falciparum malaria randomized to receive one of the three drug combinations. Fever and parasite clearance times were similar in all treatment groups. Mean drug-attributable fall in hematocrit (DAFH), defined as difference between hematocrit values pre- and 3 d post-initiation of treatment, was low (< 4.5%) and rates of recovery from MAA were similar with all treatments. Mean areas under curve (AUCs) of the plot of deficit in hematocrit levels from 30% versus time in anemic children were similar in all groups. All regimens were well tolerated. AL, AAcf and AAcp cleared fever and parasitemia rapidly and had similar rates of resolution of MAA after treatment in malarious Nigerian children.