RU2698623C1 - Method of predicting a risk of complications of unipolar transurethral enucleation of benign prostatic hyperplasia - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention refers to medicine, namely to urology, and can be used in predicting a risk of complications of unipolar transurethral enucleation of benign prostatic hyperplasia. That is ensured by determining the A index characterizing the predicted outcome of the operation with respect to the possible intraoperative complications. An indicator B characterizing the predicted outcome of the operation with respect to possible early postoperative complications is determined. These values are calculated on the basis of informative risk factors of the patient proceeding from the data of his interrogation, measured risk factors of the patient characterizing his / her current state, determination of transformed values of risk factors expressed in conditional points. Probable risk of complications is predicted on the basis of ratio between indicators A and B. At that, if A<B, the probability of possible complications is high. If A≥B, the probability of complications is low.

EFFECT: method provides accurate and reliable prediction of possible intraoperative and postoperative complications in BPH patients by taking into account the relationship between risk factors and clinical-laboratory, as well as instrumental indices.

1 cl, 6 tbl, 1 ex

Description

The invention relates to medicine, namely to urology, and can be used to predict the occurrence and development of complications of surgical interventions on the prostate gland, including by the method of monopolar transurethral enucleation (hereinafter - M-TUE) in patients with benign prostatic hyperplasia (hereinafter - BPH) )

A known method for predicting the risk of complications of cardiac diseases, including determining informative risk factors for a patient based on his survey data, measuring patient risk factors characterizing his current condition, determining converted risk factors expressed in conditional scores, and predicting the likely risk of complications based on the calculated dependencies, taking into account the significance level of each risk factor, expressed in conditional points (see RF patent for invention No. 2599372, IPC АВВ 10/00, publ. 10.10.2 016). However, this method is not applicable to the prediction of the occurrence and development of complications of surgical interventions on the prostate gland, including the M-TUE method in patients with BPH.

Also known is a method for predicting the risk of complications of surgical interventions during coronary artery bypass grafting surgery, including determining patient informative risk factors based on data from his survey, measuring patient risk factors characterizing his current condition, determining converted risk factors expressed in conditional scores, and predicting the probable the risk of complications based on the calculated dependence taking into account the significance level of each risk factor, expressed in conditional crystals (see. Russian patent №2571715, IPC A61V 10/00, publ. 20.12.2015). However, this method is also not applicable to the prediction of the occurrence and development of complications of surgical interventions on the prostate gland, including the M-TUE method in patients with BPH ..

The proposed method aims to solve the problem and achieve a technical result, which consists in increasing the accuracy and reliability of predicting possible intraoperative and postoperative complications after M-TUE in patients with BPH in order to increase the effectiveness of surgical treatment, reduce the number of complications and the length of hospital stay.

The proposed method is based on the results of our own material and domestic urological surgeons who used this operation. The following were considered:

- prognostically significant predisposing and provoking factors affecting the prognosis of intraoperative and postoperative surgical complications in the preoperative period,

- the role and influence of a combination of indicators of clinical, instrumental and laboratory studies during such an operation on the mechanism of the formation of complications during and after the operation at various times,

- evaluated from them significant for predicting the effectiveness or quality of the operation performed.

To predict possible complications of M-TUE in patients with BPH, we used:

- an interdisciplinary approach in assessing the clinical status of the patient before and after surgery in the period from a few days to 3-6-12 months,

- correlation analysis of the dependence of the development of complications on the effects of concomitant and comorbid diseases using Biostat programs,

- regression analysis of the dependence of the development of complications on numerous risk factors and clinical, laboratory and instrumental parameters using the program Statistica 6.0.,

- the reliability of the direct correlation, taking into account the Bonferroni correction as p _calc = 0.002 <p = 0.016,

- a discriminant analysis method to determine which of the variables (multiple indicators and risk factors) contributes to discrimination between the totality of variables.

Validity was established by evaluating a retrospective analysis of studies by a number of authors from the literature and patients from the control group who underwent laser enucleation of the prostate gland. A total of 139 operations.

To conduct mathematical modeling of the prognosis of complications, a sample was formed (15 out of 56 risk factors), which included patients with information about postoperative complications, with the conversion of risk factors into conditional scores, namely, 0 - no deviations from the norm, 1 - presence any deviation from the norm.

To build a prognostic model from the general level of technology in relation to an unfavorable prognosis, risk factors were selected and evaluated that can be easily interpreted without the use of costly and invasive procedures.

Risk factors and their values, converted into conditional points, are presented in table 1.

At the same time, part of the risk factors, for example, such informative risk factors X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X ₇ , X ₈ , X _{9, were} determined based on the data of a survey or examination of the patient, and part, X ₆ , X ₁₀ , X ₁₁ , X ₁₂ , X ₁₃ , X ₁₄ according to the results of measuring the patient's risk factors (laboratory and instrumental examination), characterizing his current state.

When choosing prognostically important factors, the Forward stepwise modeling option was used, i.e. with step by step adding indicators. At each step, we looked through all the variables and found the one that contributes to the difference between the populations. Using this variant of discriminant analysis allowed the reduction of variables from 56 to 15 prognostically significant factors. Based on the frequency of occurrence of each factor in groups of patients with complications and without complications, significance levels for each risk factor were calculated.

The analysis of the influence of factors on the significance level before the operation is presented in table 2.

The conclusion about the statistical significance of the relationship of clinical, laboratory, and instrumental factors deserves 97.99% confidence.

The mathematical formula for an individual preoperative prognosis of complications (intraoperative complications) during M-TUE based on the evaluation of statistical data is obtained from the sum of the products of the significance level by the values of the conditional scores of each factor of a particular patient and the addition of a free member of the regression:

A = 0.369 + 0.0342 × X ₁ + 0.0065 × X ₂ + 0.0131 × X ₃ + 0.7991 × X ₄ + 0.0310 × X ₅ + 0.6913 × X ₆ + 0.2575 × X ₇

+ 0.0517 × X ₈ + 0.4272 × X ₉ + 0.0347 × X ₁₀ + 0.1242 × X ₁₁ + 0.0379 × X ₁₂ + 0.0432 × X ₁₃ + 0.4626 × X ₁₄ + 0.8050 × X ₁₅ , or indicator A, which characterizes the predicted outcome of the operation with respect to possible intraoperative complications, is determined by the formula:

where, D = 0.3690 is the free member of the regression, α _i is the significance level for the i-th risk factor, X _i is the converted value of the i-th risk factor before the operation, expressed in conditional points, while the risk factors are: X ₁ - urological operations in history, with X ₁ = 0 in the absence of operations and X ₁ = 1 if the operation took place; X ₂ - age, with X ₂ = 0 at the age of ≤60 years and X ₂ = 1 at the age of> 60 years; X ₃ - signs of coagulant and / or thrombotic and / or aggregation disorders, including a history of hematuria of varying severity and / or hemorrhage of various origins, with X ₃ = 0, if there were no violations, and X ₃ = 1, if any of the violations noted has occurred; X ₄ - acute or recurrent urinary retention (including a history), with X ₄ = 0 if there was no delay, and X ₄ = 1 if there was a delay; X ₅ - acute and / or chronic, and / or exacerbation of inflammatory and infectious diseases of the lower urinary tract, including a history, with X ₅ = 0, if there were no violations, and X ₅ = 1, if any of these pathologies had a place; X ₆ - IPSS value, with X ₆ = 0 if IPSS <4, and X ₆ = 1 if IPSS>4; X ₇ - the presence of diabetes mellitus, with X ₇ = 0 in the absence of diabetes and X ₁ = 1 if diabetes occurs; X ₈ - the presence of hypertension and / or coronary heart disease and / or cardiac arrhythmias, with X ₈ = 0 in the absence of a violation and X ₈ = 1 if any of these pathologies occurred; X ₉ - the presence of 2 or more concomitant and / or comorbid diseases, with X ₉ = 0 if there were no diseases, and X ₉ = 1 if any of the diseases occurred; X ₁₀ - the value of hemoglobin, while X ₁₀ = 0 if hemoglobin ≥146 g / l, X ₁₀ = 1 if hemoglobin <146 g / l; X ₁₁ - the value of the concentration of sodium in the blood, while X ₁₁ = 0, if the concentration is ≥140 mmol / l, X ₁₁ = 1, if the concentration is <140 mmol / l; X ₁₂ is the size of the pancreas by TRUS, with X ₁₂ = 0 if the size is ≤25 cm ³ , X ₁₂ = 1 if the volume is> 25 cm ³ ; X ₁₃ is the volume of residual urine, with X ₁₃ = 0 if the volume is ≤50 ml, X ₁₃ = 1 if the volume is more than> 50 ml; X ₁₄ is the value of Q _max , while X ₁₄ = 0 if the value of Q _max ≥15 ml / s and X ₁₄ = 1 if the value of Q _max <15 ml / s; X _{] 5} - the estimated duration of the operation, with X ₁₅ = 0 for a duration of ≤90 min and X ₁₅ = 1 for a duration of> 90 min; and significance levels correspond to risk factors and have the following values: α ₁ = 0.0342, α ₂ = 0.0065, α ₃ = 0.0131, α ₄ = 0.7991, α ₅ = 0.0310, α ₆ = 0 , 6913, α ₇ = 0.2575, α ₈ = 0.0517, α ₉ = 0.4272, α ₁₀ = 0.0347 α ₁₁ = 0.1242, α ₁₂ = 0.0379, α ₁₃ = 0.0432 , α ₁₄ = 0.4626, α ₁₅ = 0.8050.

At the same time, it is believed that with a value of A≥3.0, the probability of possible intraoperative complications is high, with 3.0> A≥1 the probability is moderate, with A <1.0 it is low or absent.

Similarly, a variance analysis of the influence of factors was carried out according to the significance level after the operation, the results of which are presented in Table 3.

The indicator B is determined, which characterizes the predicted outcome of the operation with respect to possible early postoperative complications according to the formula

B = (-) 0,7640 + 0,0342 × X 1P + 0,0065 × X _2P + 0,0131 × X _3P + 0,7991 × X _4P X + 0,0310 × _5P + 0,6913 × X _6P +

0.2575 × X _7P + 0.0517 × X _8P + 0.4272 × X _9P + 0.0347 × X _10P + 0.1242 × X _11P + 0.0379 × X _12P + 0.0432

× X _13P + 0.4626 × X _14P + 0.8050 × X _15P

or indicator B is determined by the formula:

where, G = (-) 0.7640 is the free term of the regression, α _iP is the significance level for the ith risk factor, X _iP is the converted value of the i-th risk factor after the operation, expressed in conditional points, while α _{iP are} similar the above α _i when determining the indicator A.

At the same time, it is believed that with a value of indicator B≥3.0, the probability of possible early postoperative complications after surgery is high, with 3.0> B≥1.0 - average, with B <1.0 - low or absent

If the digital indicator A <B, then the prognosis of late postoperative complications is unfavorable, and with A≥B there is a low probability of complications.

The implementation of the proposed method for predicting the risk of complications of monopolar transurethral enucleation of benign prostatic hyperplasia can be shown in the following example.

A patient 68 years old (X ₂ ), turned to a consultation in the clinic of urology of the First MGMU them. THEM. Sechenova 10/29/17, with complaints of difficulty, a languid stream of urination, a feeling of incomplete emptying of the bladder, night pollakiuria up to 4 times. From the anamnesis, he considers himself ill for the past 3 years, when he began to note the above complaints. No previous urological operations (X ₁ ) in the anamnesis were carried out, there were no urinary retention (X ₄ ). Suffers from type 2 diabetes mellitus (X ₇ ), grade 2 arterial hypertension with a risk level of 4 (X ₈ ), post-infarction cardiosclerosis (X ₉ ) and is therefore forced to constantly take anticoagulants (X ₃ ). The physique is hypersthenic (X ₉ ). Ambulatory previously conducted therapy for chronic prostatitis (X ₅₎ antibacterial, antiinflammatory, immunomodulating drugs and improving regional blood circulation. A detailed urological examination revealed benign prostatic hyperplasia of the 1st st., Left kidney stone (X ₉ ); IPSS = 14 (X ₆ ), results of uroflowmetry: Q _max -4.6 ml / s (X ₁₄ ); residual urine volume of 20 ml (X ₁₃ ); the volume of the prostate gland according to TRUS 74 cm ² (X ₁₂ ), dysfunction of the bladder according to the combined echo-urodynamic study has not been established; in urine tests, deviations and dysfunctions of the upper urinary tract were not detected; hemoglobin in the blood 147 g / l (X ₁₀ ), hematocrit 43.6%. The concentration of sodium is 130 mmol / L (X ₁₁ ). The secret of the prostate without deviations.

The patient had a history of post-infarction cardiosclerosis with impaired heart rhythm: sinus node weakness syndrome (X ₉ ). This required, as a preoperative preparation, to establish a pacemaker for the patient. Under the supervision of cardiologists, it was necessary to conduct M-TUE against the background of temporary endocardial stimulation and the appointment of anticoagulation and antiplatelet therapy (X ₃ ).

Considering cardiac pathology, the presence of signs of infravesical obstruction, the presence of concomitant and comorbid diseases, the use of anticoagulant drugs, the likelihood of prolonged surgery was increased (X ₁₅ ).

According to the mathematical formula of the individual preoperative prediction of the risk of intraoperative complications, based on the assessment of clinical, instrumental and laboratory examination results, a mathematical transformation is performed, which is presented in table 4.

Determination of the prognosis of intraoperative complications A = 0.369 + 0.0342 × 0 + 0.0065 × 1 + 0.0131 × 1 + 0.7991 × 0 + 0.0310 × 1 + 0.6913 × 1 + 0.2575 × 1 + 0.0517 × 1 + 0.4272 × 1 + 0.0347 × 0 + 0.1242 × 1 + 0.0379 × 1 + 0.0432 × 0 + 0.4626 × 1 + 0.8050 × 1 = 3, 2770

This indicator A corresponds to a high level of risk of intraoperative complications.

10.30.17, the operation was performed: monopolar transurethral enucleation of the prostate. Enucleation was performed by a monopolar electrode. After enucleation of a large volume of hyperplastic tissues, a standard loop using the “mushroom” technique performed morsement. Complication during the operation in the form of significant bleeding from the bed of removed tissue, which was stopped at the end of the operation. The duration of the operation is 120 minutes: enucleation time is 60 minutes, the time of morculation is 60 minutes. The dry residue was 50 g. The urethral catheter was removed on the 3rd day, after a few hours the patient had a sharp difficulty in self-urination, although there were few blood clots in the wash fluid and there was no further staining with blood. Self urination is very difficult. A urethral catheter was reinstalled. In the analysis of urine, leukocytes and erythrocytes in the fields of vision are insignificant, there is no growth of microflora. In the control complex urodynamic study revealed moderate hyporeflexia, hypotension of the bladder, decreased contractile activity of the detrusor, signs of infravesical obstruction. Against the background of conservative treatment, a significant improvement in the patient's condition was noted.

We determine the ratio of indicators of the regression coefficient with indicators of risk factors after surgery, which is presented in Table 5.

Determining the prognosis of postoperative complications

B = -0.7640 + 0.0342 × 0 + 0.0065 × 1 + 0.0131 × 0 + 0.7991 × 1 + 0.0310 × 0 + 0.6913 × 1 + 0.2575 × 1 + 0 , 0517 × 1 + 0.4272 × 1 + 0.0347 × 1 + 0.1242 × 1 + 0.0379 × 0 + 0.0432 × 0 + 0.4626 × 1 + 0.8050 × 1 = 2.8958 ,

which corresponds to the average level of risk of early postoperative complications. Since A> B (3.2770 and 2.8958, respectively), the likelihood of developing late complications is low or absent.

In the control complex urodynamic study in connection with acute urinary retention after removal of the urethral catheter after surgery revealed moderate hyporeflexia, hypotension of the bladder, decreased contractile activity of detrusor, signs of infravesical obstruction. The bladder was again drained by a urethral catheter. Conservative therapy was performed. Indicators of the studied factors before and after the operation are presented in table 6.

The patient was discharged on day 5 for outpatient monitoring. During the control urodynamic and ultrasound examination after 1 month from the time of the operation, no data were found indicating a violation of the function of the bladder and the presence of infravesical obstruction (including Schafer's formula). Self-urination recovered.

3 months after the operation: IPSS = 3, QoL = 1; results of uroflowmetry - Q _max - 23.6 ml / s, Q cf. - 14.4 ml / s, urine volume 206 ml; there is no residual urine.

The above clinical observation in accordance with this example shows:

- at the time of the operation marked bleeding due to the need to use anticoagulant therapy before surgery,

- acute violation of self-urination, which developed in the early postoperative period due to hypotension and hyporeflexia of the detrusor with the phenomena of infravesical obstruction after removal of the average volume of hyperplastic tissue.

The occurrence of detrusor dysfunction was most likely due to its intraoperative overstretching (despite the use of a resectoscope with constant irrigation), as well as a reaction to surgical trauma in the neck of the bladder. If it was not possible to urinate independently in the near postoperative period, urethral re-catheterization was performed (there were no signs of hemorrhagic disturbances) followed by QUD, which made it possible to find out the causes of this complication and carry out appropriate treatment.

Eventually:

- indicator A greater than 3 before surgery indicated a high level of risk of intraoperative complications, which was confirmed by increased bleeding and developed acute urinary retention due to the hypotonic state of the bladder, atony of detrusor and infravesical obstruction,

- indicator B after surgery is less than 3, which corresponded to the average level of risk of early complications, which was confirmed by the need for repeated catheterization of the bladder and conservative corrective treatment due to acute urinary retention,

- indicator A is numerically greater than indicator B, which indicated that there was no risk of developing late complications, which was confirmed by the normalization of the patient's condition by the time of discharge on the 5th day and after 3 months.

Thus, a statistically obtained mathematical model for predicting intra- and postoperative complications provides the possibility of more accurate prediction of the development of early and late complications after M-TUE in patients with BPH to increase the effectiveness of surgical treatment. Using canonical correlation analysis allowed us to find the relationship between risk factors and clinical, laboratory and instrumental indicators. A quantitative relationship was established between the likelihood of intra- and postoperative complications and their severity, as well as to evaluate the effectiveness of the performed surgical intervention.

Claims (9)

A method for predicting the risk of complications of monopolar transurethral enucleation of benign prostatic hyperplasia, including determining patient informative risk factors based on data from his survey, measuring patient risk factors characterizing his current condition, determining converted risk factors expressed in conditional scores, and predicting the likely risk of complications based on the calculated dependence taking into account the significance level of each risk factor, expressed in conditional points . in this case, the indicator A is determined, which characterizes the predicted outcome of the operation with respect to intraoperative complications according to the formula:

where, D = 0.3690 is the free member of the regression, α _i is the significance level for the i-th risk factor, X _i is the converted value of the i-th risk factor before the operation, expressed in conditional points, while the risk factors are: X ₁ - urological operations in history, with X ₁ = 0 in the absence of operations and X ₁ = 1 if the operation took place; X ₂ - age, with X ₂ = 0 at the age of ≤60 years and X ₂ = 1 at the age of> 60 years; X ₃ - signs of coagulant and / or thrombotic and / or aggregation disorders, including anamnesis, and / or hematuria of varying severity, and / or hemorrhage of various origins, with X ₃ = 0, if there were no violations, and X ₃ = 1, if any of the noted violations occurred; X ₄ - acute or recurrent urinary retention (including a history), with X ₄ = 0 if there was no delay, and X ₄ = 1 if there was a delay; X ₅ - acute and / or chronic, and / or exacerbation of inflammatory and infectious diseases of the lower urinary tract, including a history, with X ₅ = 0 if there was no pathology, and X ₅ = 1 if any of these pathologies had a place; X ₆ is the value of IPSS (Questionnaire of the international system for the total assessment of symptoms in diseases of the prostate gland), with X ₆ = O if IPSS≤4, and X ₆ = 1 if IPSS>4; X ₇ - the presence of diabetes mellitus, with X ₇ = 0 in the absence of diabetes and X ₁ = 1 if diabetes occurs; X ₈ - the presence of hypertension (arterial hypertension) and / or coronary heart disease (coronary heart disease), and / or cardiac arrhythmias, with X ₈ = 0 in the absence of pathologies X ₈ = 1 if any of these pathologies occurred; X ₉ - the presence of two or more concomitant and / or comorbid diseases, with X ₉ = 0 if there were no diseases, and X ₉ = 1 if the disease occurred; X ₁₀ - the value of hemoglobin, while X ₁₀ = 0 if hemoglobin ≥146 g / l, X ₁₀ = 1 if hemoglobin <146 g / l; X ₁₁ - the value of the concentration of sodium in the blood, while X ₁₁ = 0, if the concentration is ≥140 mmol / l, X ₁₁ = 1, if the concentration is <140 mmol / l; X ₁₂ is the size of the pancreas (prostate gland) according to TRUS (transrectal ultrasound examination of the prostate gland), with X ₁₂ = 0 if the size is ≤25 cm ³ , X ₁₂ = 1 if the volume is> 25 cm ³ ; X _{] 3} - the volume of residual urine, with X ₁₃ = 0, if the volume is <50 ml, X ₁₃ = 1, if the volume is ≥50 ml; X ₁₄ - the value of Q _max (maximum speed of urination), while X ₁₄ = 0 if the value of Q _max ≥15 ml / s and X ₁₄ = 1 if the value of Q _max <15 ml / s; X ₁₅ is the estimated duration of the operation, with X ₁₅ = 0 for a duration of ≤90 min and X ₁₅ = 1 for a duration of> 90 min; and significance levels correspond to risk factors and have the following values: α ₁ = 0.0342, α ₂ = 0.0065, α ₃ = 0.0131, α ₄ = 0.7991, α ₅ = 0.0310, α ₆ = 0 , 6913, α ₇ = 0.2575, α ₈ = 0.0517, α ₉ = 0.4272, α ₁₀ = 0.0347, α ₁₁ = 0.1242, α ₁₂ = 0.0379, α ₁₃ = 0, 0432, α ₁₄ = 0.4626, α ₁₅ = 0.8050; and consider that with indicator A≥3.0, the probability of possible intraoperative complications is high, with 3.0> A≥1 - average, with A <1.0 - low or absent; determine the indicator, which characterizes the predicted outcome of the operation in relation to early postoperative complications according to the formula:

where G = - 0.7640 is the free member of the regression, α _iP is the significance level for the i-th risk factor, X _iP is the converted value of the i-th risk factor after the operation, expressed in conditional points, while α _{iP are} similar to the above α _i in determining indicator A, and consider that with an indicator of B≥3.0, the probability of possible early postoperative complications is high, with 3.0> B≥1.0 - average, with B <1.0 - low or absent; determine the ratio between indicators A and B and consider that with A <B the probability of possible late postoperative complications is high, with A≥B - low.