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ORIGINAL ARTICLE
Year : 2020  |  Volume : 7  |  Issue : 2  |  Page : 41-46

Hemodynamic assessment and study of bleeding complications following percutaneous renal biopsy in a tertiary care hospital


1 Department of Nephrology, Vijayanagar Institute of Medical Sciences, Bellary, Karnataka, India
2 Department of Community Medicine, Vijayanagar Institute of Medical Sciences, Bellary, Karnataka, India

Date of Submission19-May-2020
Date of Decision04-Jan-2021
Date of Acceptance27-Feb-2021
Date of Web Publication25-Aug-2021

Correspondence Address:
Dr. Maniyar Iqbal Anvar
Department of Nephrology, Vijaynagar Institute of Medical Sciences, Bellary, Karnataka
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jina.jina_6_20

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  Abstract 


Background: Percutaneous kidney biopsy is the primary diagnostic tool used in kidney diseases. In general, it is a low-risk procedure in a majority of the patients, however, complications do occur and the most common complications are pain abdomen and bleeding which may be microscopic or macroscopic hematuria or perirenal hematoma. We aim to assess all the biopsies performed by following the patients postprocedure. Materials and Methods: All patients were evaluated before renal biopsy with prebiopsy investigations like Hemoglobin percentage, platelet count, and other test for coagulation. Following which patients underwent ultrasound guided renal biopsy. post renal biopsy they were followed clinically for pulse rate , blood pressure and laboratory monitoring by repeat hemoglobin levels, and by ultrasound scan for any hematoma and visible hematuria. The results were compared to prebiopsy values and tabulated and difference in values were assessed. Results: We enrolled 88 patients in our study done over 3 years; out of 88 patients enrolled, we found that 58% of the patients were male and 42% were female; following biopsy, pain abdomen was the most common symptom reported in 50% of the patients, followed by hematuria in 33% of the patients. Out of 88 patients, 57 patients (64%) had a decrease in Hb from their prebiopsy levels, but the range was 0.1g/dl-3.4g/dl drop with a mean value of 0.932 ± 0.819 g%. Seventeen patients (19.3%) developed hematoma on day 1 following biopsy with a size ranging from 1 cc to 25 cc hematoma with a mean size of 3 cc, which decreased in size on follow-up scans to 3 (3.4%) patients on day 3 having persistent hematoma with a Median size of 4cc on day 3. The odds ratio (O.R) for developing hematoma following kidney biopsy was assessed in different groups. It was found that those patients who had their baseline serum creatinine >3mg/dl had O R of 1.66 95% C.I, [0.53-5.07]. And those patients whose systolic blood pressure was >160 mm of Hg had an Odds Ratio of developing hematoma of O.R 2.77 95% C.I [0.43-11.08]. Conclusion: Renal biopsy is a relatively safe procedure with some morbidity and occasional mortality if performed by screening of patients thoroughly for bleeding parameters, and patients may require monitoring postprocedure by repeated ultrasound scans if needed. Moreover, bleeding in many patients is clinically insignificant rarely requiring any transfusion postprocedure. Moreover, patients with high prebiopsy creatinine have some risk of bleeding than other patients with normal kidney function.

Keywords: Bleeding, hematoma, hematuria, kidney biopsy


How to cite this article:
Anvar MI, Raghavendra B. Hemodynamic assessment and study of bleeding complications following percutaneous renal biopsy in a tertiary care hospital. J Integr Nephrol Androl 2020;7:41-6

How to cite this URL:
Anvar MI, Raghavendra B. Hemodynamic assessment and study of bleeding complications following percutaneous renal biopsy in a tertiary care hospital. J Integr Nephrol Androl [serial online] 2020 [cited 2022 Aug 14];7:41-6. Available from: http://www.journal-ina.com/text.asp?2020/7/2/41/324508




  Introduction Top


Percutaneous biopsy of native kidneys is an important tool as a diagnostic modality for clinicians seeking tissue diagnosis of kidney diseases and also for prognosticating the kidney diseases. Its use following renal transplant to diagnose rejection, calcineurin inhibitor toxicity, recurrence of original disease, and infections is a different subject altogether. The primary risk of percutaneous kidney biopsy range from mild complications such as postbiopsy pain, mild hematuria to gross hematuria, and major complications such as large hematomas requiring blood transfusion, uncontrolled bleeding requiring embolization or surgical nephrectomy, and rarely death.[1] The technique for obtaining tissue has evolved with the emergence of direct ultrasound guidance as a standard of care, dramatically improving procedural safety and diagnostic yield.[2]

Percutaneous renal biopsy is generally performed as an out patient procedure or Day care Procedure and safety of the procedure has been confirmed in many studies in patients who are at low risk group for bleeding.[3],[4],[5],[6]


  Materials and Methods Top


Study design

This is a single center, where a prospective, observational case series study was conducted from August 2015 to August 2018 over a period of 3 years at the department of nephrology with the help of the radiology department of a tertiary care hospital of South India.

Inclusion criteria

All patients who were admitted and had a clinical indication for establishing diagnosis of renal disease with native kidneys and who were more than 18 years were enrolled in the study. These patients were assessed for hemoglobin percentage , platelet count, bleeding time, clotting time , prothrombin time(PT) , activated partial thromboplastin time (APTT) , International Normalized Ratio(INR) . If all Parameters were within permissible limits we proceeded for biopsy.

Exclusion criteria

Patients who had congenital malformation of kidneys, polycystic kidneys, children below 18 years , patients with transplanted kidneys , patients with prolonged bleeding time, clotting time, prolonged prothrombin time(PT), Prolonged Activated partial thromboplastin time(APTT), Prolonged International Normalized ratio(INR) were excluded from study.

Procedure

Biopsy was performed by a team led by a nephrologist and guided by a radiologist with real-time ultrasound machine of Philips company model HD 11 and HD 5 machines. Biopsy was performed with spring-loaded biopsy device.[7] We performed our biopsies with Bard kidney biopsy gun of 18G (internal diameter: 300–400 μm) which is bigger than the adult glomerulus (200–250 μm). The length of the device is 20 cm. We have taken two shoots of sample for majority of the patients: one for light microscopy and one for immunofluorescence microscopy. For some patients, we took three shoots if we could not get adequate tissue in two shoots.

Follow-up

Post renal biopsy all patients were closely monitored for any immediate and delayed complication. They were monitored on an hourly basis initially for there pulse rate, blood pressure, abdominal girth, assessment of pain and providing analgesia for approximately 6 hours or until they stabilize clinically. All patients were subjected to follow up ultrasound scans for detecting perinephric hematoma and for any visible ureteric or bladder clots. They were also assessed for any visible hematuria. Patients were also assessed for repeat Hb concentration and compared with prebiopsy Hb concentration. Furthermore, if patients had hematoma, they were followed up for further ultrasound scans till hematomas resolved.

Written informed consent was obtained from all patients or caregivers. The study protocol was approved by the institutional ethics committee.

Sample size

Since this was an observational study, we were able to enroll 88 patients who underwent renal biopsy for different reasons over a period of 3 years.

Statistical methods

The collected data were enrolled in Excel Sheet. After data filtration, the datasheet was transferred and analyzed using the SPSS software version 20.0 (SPSS South Asia, NO.2353/1-4, “Dolphin,” Bangalore, Karnataka, India). Descriptive statistics were used to describe the data variables, and the difference in the rates of outcomes among the different groups was tested using the Chi-square test. P < 0.05 was considered statistically significant.

Outcomes

Patients who underwent renal biopsy were monitored and post biopsy their clinical parameters like pulse rate, blood pressure, abdominal girth were recorded in case record form. Post biopsy investigations like hemoglobin percentage, hematuria assessment, and post biopsy hematomas were assessed and documented in case record form. And then into excel sheet. The clinical and laboratory parameters of patients who developed hematoma post renal biopsy were compared with those patients who did not developed hematomas. Then any statistical significant differences sin clinical or laboratory parameters in between two groups of patients was also assessed.Duration of hospital stay was assessed in all patients.


  Results Top


General information

A total of 88 patients were included in the study. The mean age of our study population was 36.57±(S.D 15.12) Years. Out of these 88 patients 55 patients(59.1%) were in age group of 25-55 years. Moreover, nine patients (10.2%) were more than 56 years. Nearly, 51 patients (59%) were male and 37 patients (41%) were female.

On eliciting symptoms at presentation, the most common symptoms were pedal edema in 83 patients (94.3%), puffiness of the face in 82 patients (93.2%), abdominal distension in 63 patients (71.6%), oliguria in 64 patients (72.7%), hematuria in 34 patients (38.6%), and dyspnea in 48 patients (54.5%).

Out of 88 patients pedal edema was present in 82 (93,2%) patients, puffiness of face was seen in 76(86.4%) patients and pallor was present in 46(52.3%) patients. The biochemical analysis revealed serum creatinine <1.5mg/dl in 36(40.9%) patients, more than > 3mg/dl in 24 patients(27.3%) and between 1.5-3mg/dl in 28 patients (31.8%). Regarding INR, it was mildly deranged in 60 patients (68.2%) and it was normal in 28 patients (31.8%).

Out of 88 patients in our study kidney size was more than 9 cm in length (considered as normal) in 79 patients(89.5%) and it is less than 9 cm in 9 (11%) patients. Regarding the number of attempts for biopsies, 73 patients (83%) underwent 2 attempts, 11 patients (12.5%) required 3 attempts, and 4 patients (4.5%) required one attempt for biopsy.

Following renal biopsy, we have assessed the symptoms which patient developed and found that pain at the lumbar region was seen in 44 patients (50%) out of 88 patients and hematuria was seen in 29 (33%) patients following renal biopsy.

Postbiopsy Hb levels of patients were compared to prebiopsy values to assess the impact of blood loss, and we got the following values: 57 patients (64.8%) had a decrease in Hb% values compared to prebiopsy Hb% levels and 31 patients (35.2%) had an increase in Hb% values from prebiopsy values; this increase in values could be explained by the reason that they were on diuretic usage which could have resulted in hemoconcentration. The mean decrease in Hb% was 0.932±0.819 g/dl with a range of Hb% change ranging from 0.1 to 3.4 g/dl.

Of the total 88 patients who underwent renal biopsy, 17 (19.32%) patients developed hematoma following biopsy with a range of 1 cc to 25 cc in size measured by ultrasound guidance on day 1 following biopsy with a median of 3 cc, which decreased over a period of 3 days, and on day 3, only 3 patients (3.41%) had hematoma persisting with a median size of 4 cc. At discharge, only 2 patients had hematoma persisting with a median of 2 cc size [Table 1].
Table 1: Postbiopsy hematoma among the patients

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On subgroup analysis of clinical, biochemical, and hematological parameters between two groups of patients who have developed hematoma and those who did not develop hematoma, we compared the prebiopsy values of Hb%, serum creatinine, platelet count, systolic BP, kidney size, and number of shoots (attempts) taken for biopsy in between two groups to see that there was any difference in these parameters in between these two groups.

In patients who developed perinephric hematoma following renal biopsy the mean hemoglobin percent was 10.50±2.69 g/dl, whereas it was 10.79±2.35 g/dl in patients who did not develop hematoma with P < 0.79 which was not statistically significant.

We found that the mean serum creatinine in patients who have developed hematoma was 4.28 ± 4.53 mg/dl and those who have not developed hematoma had a serum creatinine of 2.76 ± 2.30 which was less than the group which developed hematoma, but the P value was 0.05 which was not to be statistically significant [Table 2]. We found that the odds ratio (OR) of developing hematoma in patients who had serum creatinine ≥3 mg/dl was 1.66 (95% CI: 0.53–5.01).
Table 2: Comparison of clinical and hematological parameter between the groups

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We found that the mean platelet count in patients who developed hematoma was 2.84±1.43 per microliter of blood and in those patients who have not developed hematoma was 2.98±1.36 per microliter of blood and the P value was 0.702 which was not statistically significant.

We found that the systolic BP in patients who developed hematoma was 143.53 ± 30.81 mmHg and in those who did not develop hematoma was 132.25 ± 26.25 mmHg and the P value was 0.128 which was again not statistically significant [Table 2]. The OR of developing hematoma in patients who had BP ≥160 mmHg was 2.77 (95% CI: 0.63–11.08).

Only one patient of 17 had a small size kidney in patients who have developed hematoma and 8 patients of 71 who had not developed hematoma had small size kidney with P = 0.705 which was not statistically significant [Table 3].
Table 3: Comparison of clinical parameters between the groups

Click here to view


Only 2 out of 17 patients who developed hematoma required 3 attempts for biopsy, but 9 out of 71 patients who have not developed hematoma required three attempts for biopsy with P = 0.955 which was not statistically significant [Table 3].

Thus, apart from prebiopsy serum creatinine which was high but just near to being statistically significant, we could not find any clinical, biochemical, or hematological variable which was statistically significant in between two groups of patients those who develop and those who did not develop hematoma.


  Discussion Top


Renal biopsy is an irreplaceable tool for a nephrologist to determine diagnosis and prognosis and for treatment for several renal diseases. Performed in a well-trained center, it is relatively safe. However, complications do occur as the procedure is invasive, even though performed percutaneously under ultrasound guidance. In patients of high risk of bleeding, it is performed by transjugular or laparoscopic method.

The complications can be grouped into:

  1. Minor: Bleeding, asymptomatic hematoma, microscopic or gross hematuria, anemia, pain (>12 h), page kidney, perinephric infection, and arteriovenous fistula
  2. Major: Bleeding, hematoma requiring blood transfusion or invasive procedure to stop bleeding, urinary tract obstruction, with or without acute kidney injury (AKI), hypotension due to bleeding, nephrectomy, sepsis, other organ or blood vessel perforation, and death.


Renal biopsy may cause death or require extreme procedure like nephrectomy.[8],[9],[10] Hence, careful evaluation of risk/benefit ratio for the patient with counseling about the complications and informed consent is a must before biopsy. The main complication following renal biopsy is bleeding which occurs at three different places (1) In collecting ducts, ureter and bladder which can cause obstructive Acute kidney injury.(2) Below the renal capsule causing subcapsular hematoma, which may lead to page kidney, wherein there is Renal Ischemia due to prolonged extrinsic compression of kidney which will lead to high renin levels and cause secondary hypertension.[11] and (3) In perinephric space causing hematoma, which may be asymptomatic to clinically significant causing drop in hemoglobin concentration and which may require blood transfusion.

The risk of renal biopsy is not very high. In a systematic review and meta-analysis by Corapi KM et al[12] wherein they included both prospective and retrospective studies and included 9474 adults who underwent ultrasound guided renal biopsy they found that. The overall incidence of bleeding complications was as follows: transient gross hematuria –3.5%, requiring transfusion –0.9%, requiring angioembolization –0.6%, requiring nephrectomy –0.01%, and death –0.02%.[12] Thus, the risk of using invasive procedure to stop bleeding is very rare.[13],[14] Moreover, many times conservative treatment with intravenous fluid or blood transfusion[15] will suffice. Moreover, before embolization or surgery to stop bleeding, we can try off-label use of recombinant activated factor VII.[16]

Specific symptoms following biopsy

Lumbar pain was the most common symptom in 50% of our patients which was comparable to different studies showing (30%–55%).[17] A similar study done by Ishikawa et al.[18] which compared early ambulation 2 h postprocedure and 7 h postprocedure found that pain was seen in 7.5% of the patients in early ambulation and 21% for delayed ambulation.

In a systematic review of 34 studies of 9474 adult patients,[12] the incidence of hematuria was 3.5%, but in our study, we had a 33% incidence of hematuria postbiopsy. We also found that in our study out of 88 patients 57(66.8%) had a drop in hemoglobin concentration post biopsy which was more when compared to study done by Ishikawa et al[19] wherein they had 30.9% patients who had drop in hemoglobin percent. In the same study, the mean drop in Hb% was 0.43 ± 0.7 g/dl, but in our study, we had a 0.1–3.4 g/dl drop in Hb% with a mean drop of 0.932 ± 0.819 g/dl.

273 patients (86.1%) in the above study by Ishikawa et al.[19] had perinephric hematoma immediately after biopsy and 12.9% showed >2 cm hematoma, but 17 patients (19.32%) had hematoma in our study on day 1 and 13 patients (13.77%) had >2 cc hematoma.

Comparing the clinical determinants between patients who developed hematoma and those who did not develop hematoma, we found that only serum creatinine was 4.28±4.53 mg/dl in patients who developed hematoma compared to patients who did not develop hematoma which was 2.76±2.30 mg/dl which was near to be statistically significant P = 0.05. The OR of patients with serum creatinine of >3 mg/dl developing hematoma was 1.56 (95% CI: 0.53–5.01), whereas in a study done by Roccatello et al.,[20] they found that OR of patients with serum creatinine >3 mg/dl was 2.03 (95% CI: 1.18–6.81) found to be an independent risk factor for major and minor complications.

They also found that severe hypertension was an independent risk factor for bleeding complications (OR: 2.01, 95% CI: 1.2–4.7). However, in our study, the OR of patients developing hematoma who had systolic BP >160 mmHg was 2.77 (95% CI: 0.63–11.08).

In a study by Korbet et al.[9] of 1055 biopsies, the factors which predispose to complication were systolic BP >170 mmHg (OR: 4.2, 95% CI: 1.8–9.8), bleeding time >7.5 min (OR: 1.2–2.5), and serum creatinine >3.5 mg/dl (OR: 1.8, 95% CI: 1.2–2.9).

A study by Feldmann et al.[21] found that systolic BP (>155 mmHg vs. 126 mmHg, OR: 2.007, 95% CI: 1.003–4.018) (P = 0.049), young age (per 1 :year increase, OR: 0.0983, 95% CI: 0.098, P = 0.027), and interstitial fibrosis (>50% vs. <16%, OR: 2.694, 95% CI: 1.212–5.987, P = 0.015) influenced persistent Hb reduction >1 g/dl after 24 h, whereas in our case series, In our study group of 88 patients we found that 57(64.8%) patients out of 88 had a drop in hemoglobin percent from prebiopsy values. However, the mean drop was 0.932 ± 0.1814 and 17 patients (19.31%) had Hb% drop >1 g/dl over 24 h, and we did not find difference in systolic BP between hematoma and nonhematoma patients.

In a study by Potretzke et al.[22] comparing complications after percutaneous solid organ biopsies in 4756 patients between hypertensive and nonhypertensive patients, they found no significant association between hypertension and major bleeding. The incidence of bleeding in hypertensive patients was 0.4% (6/1488) which was not statistically different from normotensive patients (9/36, 0.28% P = 0.496), and subgroup analysis in kidney biopsies showed that the rate of bleeding was slightly higher in hypertensive patients (3/213, 1.4 vs. 1/355, 0.28% in normotensive patients), but the difference was not statistically significant (P = 0.185) which corroborates with a study where there was no difference in hypertensive and nonhypertensive groups (P = 0.128).

There was also no difference in the number of shoots taken during biopsy and development of hematoma. Out of 17 patients who had developed hematoma post biopsy in our study group 2(11%) patients required 3 attempts ,however in the group which did not develop hematomas 9(12.7%) patients out of 71 required 3 attempts for the biopsy, which was similar to a study done by Korbet et al.[9] where they find no difference in complication rate when stratified for number of cores taken.


  Conclusion Top


Renal biopsy is a relatively safe procedure with some complications, the most common being hematuria seen in 33%, pain abdomen seen in 50%, and hematoma seen in 19.32% in our study and only parameter which we found important for bleeding being high serum creatinine among patients with hematoma.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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Korbet SM, Volpini KC, Whittier WL. Percutaneous renal biopsy of native kidneys: A single-center experience of 1,055 biopsies. Am J Nephrol 2014;39:153-62.  Back to cited text no. 9
    
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Stratta P, Canavese C, Marengo M, Mesiano P, Besso L, Quaglia M, et al. Risk management of renal biopsy: 1387 cases over 30 years in a single centre. Eur J Clin Invest 2007;37:954-63.  Back to cited text no. 15
    
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Maksimovic B, Neretljak I, Vidas Z, Vojtusek IK, Tomulic K, Knotek M. Treatment of bleeding after kidney biopsy with recombinant activated factor VII. Blood Coagul Fibrinolysis 2012;23:241-3.  Back to cited text no. 16
    
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Potretzke TA, Gunderson TM, Aamodt D, Weisbrod AJ, Hesley GK, Welch TJ, et al. Incidence of bleeding complications after percutaneous core needle biopsy in hypertensive patients and comparison to normotensive patients. Abdom Radiol (NY) 2016;41:637-42.  Back to cited text no. 22
    



 
 
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  [Table 1], [Table 2], [Table 3]



 

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