Re-evaluation of the efficacy of tranexamic acid in reducing blood loss in percutaneous nephrolithotomy: a randomized clinical trial

Tranexamic acid for percutaneous nephrolithotomy: an abridged Cochrane review

OBJECTIVE

To assess the effects of tranexamic acid (TXA) in individuals with kidney stones undergoing percutaneous nephrolithotomy (PCNL).

PATIENTS AND METHODS

We performed a literature search of Cochrane Library, PubMed (including MEDLINE), Embase, Scopus, Global Index Medicus, trials registries, grey literature, and conference proceedings. We included randomised controlled trials (RCTs) that compared treatment with PCNL with administration of TXA to placebo (or no TXA) for patients aged ≥18 years. Two review authors independently classified studies and abstracted data. Primary outcomes were blood transfusion, stone-free rate (SFR), thromboembolic events (TEE). We rated the certainty of evidence (CoE) according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach using a minimally contextualised approach with pre-defined thresholds for minimally clinically important differences (MCID).

RESULTS

We included 10 RCTs assessing the effect of systemic TXA in PCNL vs placebo (or no TXA). Eight studies were published as full text. Based on an adjusted baseline risk of blood transfusion of 5.7%, systemic TXA may reduce blood transfusions (risk ratio [RR] 0.45, 95% confidence interval [CI] 0.27-0.76). Based on an adjusted baseline SFR of 75.7%, systemic TXA may increase SFR (RR 1.11, 95% CI 0.98-1.27). There is probably no difference in TEEs (risk difference 0.001, 95% CI -0.01 to 0.01). Systemic TXA may increase adverse events (AEs) (RR 5.22, 95% CI 0.52-52.72). Systemic TXA may have little to no effect on secondary interventions (RR 1.15, 95% CI 0.84-1.57). The CoE for most outcomes was assessed as low or very low.

CONCLUSIONS

Based on a body of evidence of 10 RCTs, we found that systemic TXA in PCNL may reduce blood transfusions, major surgical complications, and hospital length of stay, as well as improve the SFR; however, it may increase AEs. These findings should inform urologists and their patients in making informed decisions about the use of TXA in the setting of PCNL.

2022 Recommendations of the AFU Lithiasis Committee: Percutaneous nephrolithotomy

Percutaneous nephrolithotomy (Labate et al.) is the standard procedure for the treatment of large (≥2cm) kidney stones. The patient can be in prone or modified supine position. The puncture is performed under fluoroscopy and/or ultrasound guidance. The stone-free rate seems to be comparable between miniaturized and standard PCNL. Procedures performed with smaller diameter instruments tend to be associated with significant lower blood loss, but longer procedure times. The limitation of the number of percutaneous tracts results in better preservation of the kidney function and lowers the risk of complications. The use of tranexamic acid during PCNL may be interesting for reducing the bleeding risk, the transfusion rate, and possibly the intervention duration. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendation (CPR) method and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis [EAU 2022]) and their adaptability to the French context.

Tranexamic acid for percutaneous nephrolithotomy

BACKGROUND

Percutaneous nephrolithotomy (PCNL) is the gold standard for the treatment of large kidney stones but comes with an increased risk of bleeding compared to other treatments, such as ureteroscopy and shock wave lithotripsy. Tranexamic acid (TXA) is an antifibrinolytic agent that has been used to reduce bleeding complications in other settings.

OBJECTIVES

To assess the effects of TXA in individuals with kidney stones undergoing PCNL.

SEARCH METHODS

We performed a comprehensive literature search of the Cochrane Library, PubMed (including MEDLINE), Embase, Scopus, Global Index Medicus, trials registries, other sources of the grey literature, and conference proceedings. We applied no restrictions on the language of publication nor publication status. The latest search date was 11 May 2023.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that compared treatment with PCNL with administration of TXA to placebo (or no TXA) for patients ≥ 18 years old.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data. Primary outcomes were: blood transfusion, stone-free rate (SFR), and thromboembolic events (TEEs). Secondary outcomes were: adverse events (AEs), secondary interventions, major surgical complications, minor surgical complications, unplanned hospitalizations or readmissions, and hospital length of stay (LOS). We performed statistical analyzes using a random-effects model. We rated the certainty of evidence (CoE) according to the GRADE approach using a minimally contextualized approach with predefined thresholds for minimally clinically important differences (MCIDs).

MAIN RESULTS

We analyzed 10 RCTs assessing the effect of systemic TXA in PCNL versus placebo (or no TXA) with 1883 randomized participants. Eight studies were published as full text. One was published in abstract proceedings, but it was separated into two separate studies for the purpose of our analyzes. Average stone surface area ranged 3.45 to 6.62 cm2. We also found a single RCT published in full text assessing the effects of topical TXA in PCNL versus placebo (or no TXA) with 400 randomized participants, the results of which are further described in the review. Here we focus only on the results of TXA used systemically. Blood transfusion - Based on a representative baseline risk of 5.7% for blood transfusions taken from a large presentative observational studies, systemic TXA may reduce blood transfusions (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.27 to 0.76; I2 = 28%; 9 studies, 1353 participants; low CoE). We assumed an MCID of ≥ 2%. Based on 57 participants per 1000 with placebo (or no TXA) being transfused, this corresponds to 31 fewer (from 42 fewer to 14 fewer) participants being transfused per 1000. Stone-free rate - Based on a representative baseline risk of 75.7% for SFR, systemic TXA may increase SFRs (RR 1.11, 95% CI 0.98 to 1.27; I2 = 62%; 4 studies, 603 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 757 participants per 1000 being stone free with placebo (or no TXA), this corresponds to 83 more (from 15 fewer to 204 more) stone-free participants per 1000. Thromboembolic events - There is probably no difference in TEEs (risk difference (RD) 0.00, 95% CI -0.01 to 0.01; I2 = 0%; 6 studies, 841 participants; moderate CoE). We assumed an MCID of ≥ 2%. Since there were no thromboembolic events in intervention and/or control groups in 5 out of6 studies, we opted to assess a risk difference with systemic TXA for this outcome. Adverse events - Systemic TXA may increase AEs (RR 5.22, 95% CI 0.52 to 52.72; I2 = 75%; 4 studies, 602 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 23 participants per 1000 with placebo (or no TXA) having an adverse event, this corresponds to 98 more (from 11 fewer to 1000 more) participants with adverse events per 1000. Secondary interventions - Systemic TXA may have little to no effect on secondary interventions (RR 1.15, 95% CI 0.84 to 1.57; I2 = 0%; 2 studies, 319 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 278 participants per 1000 with placebo (or no TXA) having a secondary intervention, this corresponds to 42 more (from 44 fewer to 158 more) participants with secondary interventions per 1000. Major surgical complications - Based on a representative baseline risk for major surgical complications of 4.1%, systemic TXA may reduce major surgical complications (RR 0.36, 95% CI 0.21 to 0.62; I2 = 0%; 5 studies, 733 participants; moderate CoE). We assumed an MCID of ≥ 2%. Based on 41 participants per 1000 with placebo (or no TXA) having a major surgical complication, this corresponds to 26 fewer (from 32 fewer to 16 fewer) participants with major surgical complications per 1000. Minor surgical complications - Systemic TXA may reduce minor surgical complications (RR 0.71, 95% CI 0.45 to 1.10; I2 = 76%; 5 studies, 733 participants; low CoE). We assumed an MCID of ≥ 5%. Based on 396 participants per 1000 with placebo (or no TXA) having a minor surgical complication, this corresponds to 115 fewer (from 218 fewer to 40 more) participants with minor surgical complications per 1000. Unplanned hospitalizations or readmissions - We are very uncertain how unplanned hospitalizations or readmissions are affected (RR 1.55, 95% CI 0.45 to 5.31; I2 = not applicable; 1 study, 189 participants; very low CoE). We assumed an MCID of ≥ 2%. Hospital length of stay - Systemic TXA may reduce hospital LOS (mean difference 0.52 days lower, 95% CI 0.93 lower to 0.11 lower; I2 = 98%; 7 studies, 1151 participants; low CoE). We assumed an MCID of ≥ 0.5 days.

AUTHORS' CONCLUSIONS

Based on 10 RCTs with substantial methodological limitations that lowered all CoE of effect, we found that systemic TXA in PCNL may reduce blood transfusions, major and minor surgical complications, and hospital LOS, as well as improve SFRs; however, it may increase AEs. We are uncertain about the effects of systemic TXA on other outcomes. Findings of this review should assist urologists and their patients in making informed decisions about the use of TXA in the setting of PCNL.

Systematic review of hematuria and acute renal failure with tranexamic acid

OBJECTIVES

To conduct a systematic review of tranexamic acid (TXA) and the risk of renal failure from urinary clots in adult patients with hematuria.

METHODS

A systematic review of Medline, Embase, CENTRAL, www.

CLINICALTRIALS

gov, and Google Scholar were searched. Randomized control trials (RCTs) and observational studies that assessed the risk of renal failure with use of TXA among adults with hematuria were included. The primary outcome was renal failure due to urinary tract clots with TXA compared to no TXA (or placebo) or comparator.

RESULTS

We identified three RCTs (N = 466 patients) and three retrospective cohort studies (N=220 patients), and a total of 342 patients that had hematuria and received TXA. The patient population of the six studies included medical and surgical patients, with two of the three RCTs comprised patients undergoing percutaneous nephrolithotomy, and the third RCT comprised patients undergoing transurethral resection of the prostate. Documentation of renal function before and after TXA administration was documented in only two studies (N = 28 patients), and neither identified worsening renal function in those exposed to TXA.

CONCLUSIONS

There are limited studies evaluating the risk of renal failure in patients with hematuria who were exposed to TXA, and the available data does not suggest an increased risk.

Effect of Tranexamic Acid on Bleeding Outcomes After Percutaneous Nephrolithotomy: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Purpose: We performed a systematic review and meta-analysis of the literature to evaluate the efficacy of the routine use of tranexamic acid (TXA) during percutaneous nephrolithotomy (PCNL). Methods: This systematic review was conducted following the updated reporting guidelines from PRISMA 2020. Results: In total, 275 titles and abstracts were reviewed, of which 20 were screened to be eligible for full text review. Of these 20 articles, 11 were selected for inclusion after full article evaluations. Seven of these 11 studies were seen as having a low risk of bias with a Jadad score of ≥3. These studies were included for data extraction. Once data were extracted, 964 patients were included. The primary outcome, blood transfusion rate, showed significant reduction with a ratio for transfusion rate of 0.34 [95% confidence interval (CI) (0.19 to 0.61), z = 3.61, p = 0.0003]. Mean hemoglobin (Hgb) drop and operative time were both shown to be reduced with the use of TXA. The mean difference for Hgb drop was -0.86 [95% CI (-1.26 to -0.46), z = 4.23, p < 0.0001]. Reduction in operative time showed a mean difference of -8.45 minutes [95% CI (-15.04 to -1.86), z = 2.51, p = 0.01]. Stone clearance was not shown to differ significantly between experimental and control groups, with a risk ratio of 1.28 [95% CI (0.89 to 1.84), z = 1.31, p = 0.19]. Conclusions: This meta-analysis revealed that the routine use of TXA at time of PCNL reduces the rates of blood transfusion, mean Hgb drop, and operative time. With the low cost of TXA and strong safety profile, stronger consideration should be given to the routine use of TXA during PCNL by endoscopic surgeons.

Is There Any Clinical Benefit for Peri-operative Administration of Tranexamic Acid for Patients Undergoing Percutaneous Nephrolithotomy? A Systematic Review and Meta-analysis

PURPOSE OF REVIEW

The purpose of current systematic review and meta-analysis is to determine the efficacy and safety of the administration of tranexamic acid in patients undergoing PCNL. The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. This systematic review and meta-analysis includes randomized comparative prospective studies.

RECENT FINDINGS

The primary endpoints were the hemoglobin drop, the bleeding complications, and the transfusion rate. Secondary endpoints included the operative time, the stone-free rate, the hospital stay, and the overall complications. Two-thousand five-hundred six publications were screened for this study. Six RCTs (1262 patients) were included in the meta-analysis. As for our primary endpoints, the hemoglobin drop was lower in the tranexamic group than in the control group, with mean difference (MD) of - 0.65 (p < 0.0001); the bleeding complications were rarer in the tranexamic group than in the control group, with an odds ratio (OR) of 0.32 (p < 0.00001); and the transfusion rate was lower in the tranexamic group with an OR of 0.34 (p = 0.0007). Concerning the secondary endpoints, the operative time was less in the tranexamic group with an MD of - 10.39 (p < 0.0001), the meta-analysis of the stone-free status data showed no statistical significance between the two groups with an OR of 1.58 (p = 0.09), the hospital stay was significantly less in the tranexamic group with an MD of - 1.38 (p = 0.005), and the overall complications were rarer in the tranexamic group than in the control group with an OR of 0.34 (p = 0.12). The peri-operative use of TA contributes to the reduction of blood loss, bleeding complications, mean operative time, and hospital stay. The use of TA seemed to be safe and well tolerated in patients undergoing PCNL. PROSPERO protocol (Registration number: CRD42019122818).

The Efficacy and Safety of Tranexamic Acid in the Management of Perioperative Bleeding After Percutaneous Nephrolithotomy: A Systematic Review and Meta-Analysis of Comparative Studies

Introduction: We performed a systematic review and meta-analysis of the current literature to assess the efficacy and safety of tranexamic acid (TXA) in the management of postoperative bleeding after percutaneous nephrolithotomy (PCNL). Methods: A systematic literature review was performed in March 2021. Two reviewers independently screened, identified, and evaluated comparative studies assessing the effectiveness of TXA in preventing bleeding after PCNL when compared with placebo or no intervention. The incidence of transfusion, complete stone clearance, and complications were extracted among TXA and control groups to generate the risk ratio (RR) and corresponding 95% confidence interval (CI). Blood loss, hemoglobin (Hb) drop, length of hospital stays, and operative (OR) time were analyzed using standard mean difference (SMD) with corresponding 95% CI. Effect estimates were pooled using the inverse-variance approach with a random-effect model. Results: A total of 11 studies (8 randomized controlled trial, 1 prospective cohort, and 2 retrospective cohort studies; total 1842 patients) of low-to-moderate-quality were included in the meta-analysis. Overall pooled effect estimates demonstrated a decreased transfusion rate (RR 0.36; 95% CI 0.25 to 0.51), blood loss (SMD -0.74; 95% CI -1.14 to -0.34), and Hb drop (SMD -0.95; 95% CI -1.51 to -0.39) among patients in the TXA group when compared with those in the control. The number needed to treat was 11 to prevent one transfusion. Patients who received TXA also had improved stone clearance (RR 1.08; 95% CI 1.02 to 1.14), lower minor (RR 0.72; 95% CI 0.58 to 0.89) and major (RR 0.38; 95% CI 0.21 to 0.69) complications, shorter hospital stays (SMD -0.52; 95% CI -1.01 to -0.04) and decreased OR time (SMD -0.89; 95% CI -1.46 to -0.31). Conclusions: TXA can effectively reduce postoperative bleeding after PCNL. Future studies should identify a subset of patients who may benefit from preoperative TXA administration for PCNL.

Association of Intravenous Tranexamic Acid With Thromboembolic Events and Mortality: A Systematic Review, Meta-analysis, and Meta-regression

IMPORTANCE

Tranexamic acid (TXA) is an efficient antifibrinolytic agent; however, concerns remain about the potential adverse effects, particularly vascular occlusive events, that may be associated with its use.

OBJECTIVE

To examine the association between intravenous TXA and total thromboembolic events (TEs) and mortality in patients of all ages and of any medical disciplines.

DATA SOURCE

Cochrane Central Register of Controlled Trials and MEDLINE were searched for eligible studies investigating intravenous TXA and postinterventional outcome published between 1976 and 2020.

STUDY SELECTION

Randomized clinical trials comparing intravenous TXA with placebo/no treatment. The electronic database search yielded a total of 782 studies, and 381 were considered for full-text review. Included studies were published in English, German, French, and Spanish. Studies with only oral or topical tranexamic administration were excluded.

DATA EXTRACTION AND SYNTHESIS

Meta-analysis, subgroup and sensitivity analysis, and meta-regression were performed. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

MAIN OUTCOMES AND MEASURES

Vascular occlusive events and mortality.

RESULTS

A total of 216 eligible trials including 125 550 patients were analyzed. Total TEs were found in 1020 (2.1%) in the group receiving TXA and 900 (2.0%) in the control group. This study found no association between TXA and risk for total TEs (risk difference = 0.001; 95% CI, -0.001 to 0.002; P = .49) for venous thrombosis, pulmonary embolism, venous TEs, myocardial infarction or ischemia, and cerebral infarction or ischemia. Sensitivity analysis using the risk ratio as an effect measure with (risk ratio = 1.02; 95% CI, 0.94-1.11; P = .56) and without (risk ratio = 1.03; 95% CI, 0.95-1.12; P = .52) studies with double-zero events revealed robust effect size estimates. Sensitivity analysis with studies judged at low risk for selection bias showed similar results. Administration of TXA was associated with a significant reduction in overall mortality and bleeding mortality but not with nonbleeding mortality. In addition, an increased risk for vascular occlusive events was not found in studies including patients with a history of thromboembolism. Comparison of studies with sample sizes of less than or equal to 99 (risk difference = 0.004; 95% CI, -0.006 to 0.014; P = .40), 100 to 999 (risk difference = 0.004; 95% CI, -0.003 to 0.011; P = .26), and greater than or equal to 1000 (risk difference = -0.001; 95% CI, -0.003 to 0.001; P = .44) showed no association between TXA and incidence of total TEs. Meta-regression of 143 intervention groups showed no association between TXA dosing and risk for venous TEs (risk difference, -0.005; 95% CI, -0.021 to 0.011; P = .53).

CONCLUSIONS AND RELEVANCE

Findings from this systematic review and meta-analysis of 216 studies suggested that intravenous TXA, irrespective of dosing, is not associated with increased risk of any TE. These results help clarify the incidence of adverse events associated with administration of intravenous TXA and suggest that TXA is safe for use with undetermined utility for patients receiving neurological care.

Safety and efficacy of tranexamic acid in minimizing perioperative bleeding in extrahepatic abdominal surgery: meta-analysis

BACKGROUND

Perioperative bleeding is associated with increased morbidity and mortality in patients undergoing elective abdominal surgery. The antifibrinolytic agent tranexamic acid (TXA) has been shown to reduce perioperative bleeding and mortality risk in patients with traumatic injuries, but there is a lack of evidence for its use in elective abdominal and pelvic surgery. This meta-analysis of RCTs evaluated the effectiveness and safety of TXA in elective extrahepatic abdominopelvic surgery.

METHODS

PubMed, Embase, and ClinicalTrial.gov databases were searched to identify relevant RCTs from January 1947 to May 2020. The primary outcome, intraoperative blood loss, and secondary outcomes, need for perioperative blood transfusion, units of blood transfused, thromboembolic events, and mortality, were extracted from included studies. Quantitative pooling of data was based on a random-effects model.

RESULTS

Some 19 studies reporting on 2205 patients who underwent abdominal, pelvic, gynaecological or urological surgery were included. TXA reduced intraoperative blood loss (mean difference -188.35 (95 per cent c.i. -254.98 to -121.72) ml) and the need for perioperative blood transfusion (odds ratio (OR) 0.43, 95 per cent c.i. 0.28 to 0.65). TXA had no impact on the incidence of thromboembolic events (OR 0.49, 0.18 to 1.35). No adverse drug reactions or in-hospital deaths were reported.

CONCLUSION

TXA reduces intraoperative blood loss during elective extrahepatic abdominal and pelvic surgery without an increase in complications.

Comparison of safety and efficacy between single-tract and multiple-tract percutaneous nephrolithotomy treatment of complex renal calculi: a systematic review and meta-analysis

BACKGROUND

A systematic review and meta-analysis was conducted to explore the safety and efficacy of single-tract and multiple-tract percutaneous nephrolithotomy (PCNL) in complex renal calculi treatment.

METHODS

PubMed, Web of Science, Embase, EBSCO, and Cochrane library databases (updated November 2020) were searched for studies assessing the effect of different numbers of tracts on cases that underwent PCNL. The search strategy and study selection process were managed according to the PRISMA statement.

RESULTS

Five comparative studies were included in the meta-analysis. The multiple-tract PCNL group had a significantly increased total complications rate than the single-tract group (OR = 2.35, 95% CI = 1.71, 3.25; P < 0.00001) with insignificant heterogeneity (I2 = 0%, P = 0.52). Subgroup analysis showed there were different incidence of complications, mainly because the multiple-tract PCNL group was significantly associated with a higher rate of blood transfusion (OR = 2.99, 95% CI = 1.95, 4.57; P < 0.00001) with insignificant heterogeneity (I2 = 9%, P = 0.35). There were no differences in operation time (MD = 12.04, 95% CI = 6.36, 17.72; P < 0.0001) or hospitalization (MD = 0.54, 95% CI = 0.14, 0.95, p = 0.008). However, the singletract group had a higher stone-free rate (OR = 0.37, 95% CI = 0.19, 0.74; P = 0.005) with heterogeneity (I2 = 51%, P = 0.08), as stones in the single-tract group were smaller than those in the multiple-tract group.

CONCLUSIONS

The current research did not find that the multiple-tract group had a higher stone-free rate. Additionally, multiple-tract PCNL was associated with a higher incidence of blood transfusion and negative impact on renal function.

Tranexamic acid in patients with complex stones undergoing percutaneous nephrolithotomy: a randomised, double-blinded, placebo-controlled trial

OBJECTIVES

To assess the efficacy and safety of single-dose tranexamic acid on the blood transfusion rate and outcomes of patients with complex kidney stones undergoing percutaneous nephrolithotomy (PCNL).

PATIENTS AND METHODS

In a randomised, double-blinded, placebo-controlled trial, 192 patients with complex kidney stone (Guy's Stone Scores III-IV) were prospectively enrolled and randomised (1:1 ratio) to receive either one dose of tranexamic acid (1 g) or a placebo at the time of anaesthetic induction for PCNL. The primary outcome measure was the occurrence rate of perioperative blood transfusion. The secondary outcome measures included blood loss, operative time, stone-free rate (SFR), and complications. ClinicalTrials.gov identifier: NCT02966236.

RESULTS

The overall risk of receiving a blood transfusion was reduced in the tranexamic acid group (2.2% vs 10.4%; relative risk, 0.21, 95% confidence interval [CI] 0.03-0.76, P = 0.033; number-needed-to-treat: 12). Patients randomised to the tranexamic acid group had a higher immediate and 3-month SFR compared with those in the placebo group (29% vs 14.7%, odds ratio [OR] 2.37, 95% CI 1.15-4.87, P = 0.019, and 46.2% vs 28.1%, OR 2.20, 95% CI 1.20-4.02, P = 0.011, respectively). Faster haemoglobin recovery occurred in patients in the tranexamic acid group (mean, 21.3 days; P = 0.001). No statistical differences were found in operative time and complications between groups.

CONCLUSIONS

Tranexamic acid administration is safe and reduces the need for blood transfusion by five-times in patients with complex kidney stones undergoing PCNL. Moreover, tranexamic acid may contribute to better stone clearance rate and faster haemoglobin recovery without increasing complications. A single dose of tranexamic acid at the time of anaesthetic induction could be considered standard clinical practice for patients with complex kidney stones undergoing PCNL.

The impact of anterior calyceal stones on the outcomes of percutaneous nephrolithotomy for complex kidney stones: a comparative study

BACKGROUND

This study aimed to evaluate the possible effect of anterior calyceal stones on the surgical outcomes of percutaneous nephrolithotomy.

METHODS

Consecutive patients with complex kidney stones from 2012 to 2020 were evaluated retrospectively. In total, 219 patients were divided into 2 groups based on the presence of anterior calyceal stones (group 1; N.=89) or not (group 2; N.=130). The groups were compared in terms of surgical outcomes (i.e., stone-free rate [SFR], operation time, and hemoglobin drop) and complications.

RESULTS

The patient demographics and stone characteristics were similar between the groups. Multiple access was more frequently done in group 1 than it was in group 2 (47.2% vs. 30.8%; P=0.014), and the SFR was lower in group 1 (51.7%) than it was in group 2 (67.7%; P=0.017). Of the anterior calyceal stones in group 1, 42.6% could not be cleaned. However, when excluding patients who have only anterior residual stones from the statistical analysis, the groups had similar SFRs (68.5% vs. 67.7% for group 1 and group 2, respectively).

CONCLUSIONS

The presence of complex kidney stones with anterior calyceal extension are associated with higher residual stones rates in the anterior calyx. Also, it increases multiple access, the operation time, and level of hemoglobin drop.

Can tranexamic acid reduce the blood transfusion rate in patients undergoing percutaneous nephrolithotomy? A systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis was conducted to explore the efficacy of tranexamic acid (TXA) in reducing transfusion events in patients undergoing percutaneous nephrolithotomy (PCNL).

METHODS

PubMed, Web of Science, Embase, EBSCO, and Cochrane library databases from January 1980 to October 2019 were searched for randomized controlled trials (RCTs) that assessed TXA efficacy in reducing transfusion events during PCNL. Intervention treatments include using TXA compared with placebo (or no intervention) for patients who underwent PCNL. The search strategy and study selection process were managed in accordance with the PRISMA statement.

RESULTS

Six RCTs are included in the meta-analysis. Overall, TXA intervention groups showed a significant reduction in blood transfusion events (RR = 0.34; 95% confidence interval [CI] = 0.19 to 0.62), hemoglobin decrease (MD = -0.80; 95% CI = -1.32 to -0.28), operative time (MD = -12.62; 95% CI = -15.62 to -9.61), and length of hospital stay (MD = -0.73; 95% CI = -1.36 to -0.10) compared with control groups after PCNL. However, TXA had no substantial impact on the rate of stone clearance (RR = 1.10; 95% CI = 1.00 to 1.21).

CONCLUSIONS

TXA can effectively reduce the transfusion rate and blood loss during PCNL.