RU2330602C1 - Method of postoperative pneumonia forecasting associated with interventions on superior bodies abdominal organs - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: lung capacity and forced inspiration volume for the first second are detected by spirometry method. In addition exhalation peak pressure is detected by pneumatic tonometry within earliest postoperative period - on the 2^nd and 5^th days after operation. In case any two of three factors found: value of lung capacity for the 5^th day after operation does not exceed 130% of value thereof for the 2^nd postoperative day, value of forced inspiration volume for the first second for 5^th day after operation does not exceed 125% of value thereof for 2^nd postoperative day, value of exhalation peak pressure for 5^th day after operation does not exceed 130% of value thereof for 2^nd postoperative day, high risk of postoperative pneumonia development is forecasted after interventions on superior abdominal organs.

EFFECT: method is more effective.

1 ex, 4 tbl

Description

The invention relates to medicine, namely to internal medicine.

The development in surgical patients after surgical interventions of pneumonia is a serious complication, aggravating the course of the postoperative period. In abdominal surgery, this problem is most relevant for patients who underwent surgery on the organs of the upper floor of the abdominal cavity.

The problem of reducing the incidence and improving treatment outcomes is undoubtedly associated with a detailed study of the etiology and pathogenesis of the disease, improving methods of prevention, diagnosis and treatment. However, it should be emphasized that the effectiveness of treatment and preventive measures largely depends on the correctness of their choice on the basis of forecasting.

For the prototype, we chose a method for predicting serious respiratory complications in patients who underwent surgery on the organs of the upper floor of the abdominal cavity, described by G. Barisione et al. (Barisione G., Rovida S., Gazzaniga GM, Fontana L. Upper abdominal surgery: does a lung function test exist to predict early severe postoperative respiratory complications? // Eur. Respir. J. - 1997. - v.10. - No. 6. - P.1301-1308). G. Barisione studied the relationship between the preoperative state of the respiratory system and the risk of serious respiratory complications after surgery. For data analysis, the method of logistic regression was used. The significance of the following indicators was established in predicting postoperative respiratory complications: forced expiratory volume in the first second (FEV ₁ ), residual lung capacity (RV), lung transfer factor (diffusion capacity) for carbon monoxide (T _{L, CO, sb} ), sputum hypersecretion (SMN). The authors obtained the logistic regression equation for predicting postoperative respiratory complications

logit θ (SRCs) = 9.11-0.07 FEV ₁ % pred + 1.13 RV-0.10 T _{L, CO, sb} % pred + 4.89 CMH.

The sensitivity of this method was 84%, the specificity was 99%, the predictive value of a positive result was 95%, and the predictive value of a negative result was 98%.

A common feature of our method with the method described by G. Barisione is the patient population to which it is applicable; use for predicting data on the functional state of the external respiration apparatus. Our method differs from the one described by G. Barisione in the following: a different set of indicators is used (vital capacity of the lungs - VC, volume of forced expiration in the first second - FEV ₁ , peak expiratory pressure - MPd), more accessible for determination by practical doctors; the prognosis does not depend on preoperative values of indicators, but on their dynamics in the near postoperative period; "split points" are used.

The technical result of the proposed method is to predict the risk of developing pneumonia after surgery on the organs of the upper floor of the abdominal cavity by examining the VC and FEV ₁ by spirometry and PDId by pneumonometry in the immediate postoperative period - on the 2nd and 5th day after the operation.

In order to assess the value of indicators of the function of external respiration (HFD) for predicting the development of pneumonia after surgical interventions on the organs of the upper floor of the abdominal cavity, 78 patients were examined who underwent these interventions in a planned manner, including 19 with postoperative pneumonia (pneumonia in all cases developed after 5 day after the operation, the diagnosis is confirmed radiographically). One day before the operation, on the 2nd and 5th day after the operation, the following parameters were determined in all patients: VC, FEV ₁ , PIC (peak volume expiratory flow rate), FEV ₁ / VC by spirometry; PDvd and PDvid (peak inspiratory and expiratory pressure) were determined by pneumonometry (measuring the maximum static pressure on inspiration and expiration in the oral cavity) according to the method described by John Rees (Fig. J. Diagnostic tests in pulmonology. Transl. From English - M .: Medicine, 1994 .-- P.28-29).

It was found that the initial state of the function of external respiration affects the postoperative dynamics of the studied parameters, but is not predetermining the development of pneumonia. In all patients, on the 2nd day after surgery, there was a significant decrease in all determined parameters (they amounted to 40-60% of preoperative values). By the 5th day after the operation, an increase in FVD was observed, and in patients with subsequent pneumonia, the growth rate was less. We expressed the values of the FVD indicators on the 5th day after the operation in% of the values of the 2 postoperative days and compared the results obtained in patients with developed pneumonia (main group - 19 people) and patients who did not have respiratory complications (comparison group - 59 people ) The performance in the two groups was significantly different; the greatest differences were characteristic for VC, FEV ₁ , PDdvid. Data on these indicators are presented in table 1.

Thus, we found it possible to use the data on the dynamics of the parameters of the high pressure function in the immediate postoperative period to predict postoperative pneumonia.

The following actions were carried out: 1) for each of the three indicated indicators of the HPF, a “separation point” was determined, below which a high probability of developing pneumonia is assumed; 2) for each of the three FVD indicators, the frequency of reaching the identified threshold in the main group and the comparison group was calculated, the significance of the differences was evaluated; 3) analyzed the simultaneous occurrence of three prognostic signs in patients of both groups.

To establish the "separation point" we used reference intervals. The boundaries of the reference intervals were determined by the formula

arithmetic mean ± 1.96 * standard deviation (Petri A., Sabin K. Visual statistics in medicine. Transl. from English. - M .: GEOTAR-MED, 2003. - S.93-94). The calculation results are presented in table 2.

As the "separation point", it is recommended to use the upper or lower limit of the reference interval. In our case, the boundaries of reference intervals for two groups representing differentiable states “overlap” each other. Therefore, to determine the "separation point", we decided to use the arithmetic average of the upper limit of the reference interval of the main group and the lower limit of the reference interval of the comparison group. The following values were obtained: for VC - 128.85, for FEV ₁ - 123.38, for PDd - 128 (units of measurement are the values of the parameters of the FVD on the 5th postoperative day, the expression in% of the values of 2 postoperative days). To facilitate subsequent processing of the material and the application of the method, the obtained values were rounded to the nearest multiple of five values. As a result, “separation points” were established: for VC - 130, for FEV ₁ - 125, for PDdvd - 130 (units of measurement are the values of the FVD on the 5th postoperative day, the expression in% of the values of 2 postoperative days).

At the next stage, we determined the number of cases with values of estimated indicators not exceeding the “separation point” in the main group and the comparison group, calculated the frequency of these cases for each group, and evaluated the significance of the differences. The data processing results are given in table.3.

Thus, there are significant differences in the frequency of reaching the “separation point” for each of the three HPF indicators in the main group and in the comparison group. It is possible to recognize each of the following prognostic signs as significant: 1) if the patient's VC on the 5th day after surgery does not exceed 130% of the VC on the 2nd postoperative day, then he is more likely to develop postoperative pneumonia; 2) if the patient has an FEV value of ₁ on the 5th day after surgery does not exceed 125% of the value of FEV ₁ on the 2nd postoperative day, then he is more likely to develop postoperative pneumonia; 3) if the patient’s PDId value on the 5th day after surgery does not exceed 130% of the PDId value on the 2nd postoperative day, then he is more likely to develop postoperative pneumonia.

When analyzing the simultaneous occurrence of the three prognostic signs described above in patients of the main group and the comparison group, the following data were obtained. In the main group, 12 people (63.16%) simultaneously had all 3 signs, and 7 people (36.84%) had two of the three signs. In the comparison group, 1 person (1.7%) simultaneously had all 3 signs, 3 people (5.08%) had two of the three signs, and 9 patients (15.25%) had only 1 of the signs, in 46 people (77.97%), none of the three signs was noted. That is, in all patients of the main group, at least 2 out of 3 of the above prognostic signs were observed, while in the comparison group this condition was fulfilled only in 6.78% of cases, in the majority of individuals (93.22% ) no more than 1 of 3 prognostic signs was noted. When assessing the significance of the difference between the two groups of patients according to the following criterion - the presence of at least 2 out of 3 prognostic signs simultaneously, it was found that the difference was significant (t = 28.48; p <0.001).

As a result, a prognostic rule is formulated.

The patient is highly likely to develop postoperative pneumonia in the presence of any 2 of 3 signs: 1) the VC on the 5th day after surgery does not exceed 130% of the VC on the 2nd postoperative day; 2) the value of FEV ₁ on the 5th day after surgery does not exceed 125% of the value of FEV ₁ on the 2nd postoperative day; 3) the value of PDId on the 5th day after surgery does not exceed 130% of the value of PDId on the 2nd postoperative day.

This prognostic rule has been evaluated according to the following criteria: sensitivity, specificity, prognosticity of a positive test result, prognosticity of a negative test result, likelihood ratio for a positive result (Petri A., Sabin K. Visual statistics in medicine. Transl. From English - M .: GEOTAR-MED, 2003. - S.93-94). The initial data for calculating the listed indicators are given in the “frequency table” - table 4.

The sensitivity of the developed test was 1.0 (19/19) - 100%, specificity - 0.9322 (55/59) - 93.22%, predictive value of a positive result - 0.8261 (19/23) - 82.61%, prognosticity of a negative result - 1.0 (55/55) - 100%. The likelihood ratio for a positive test result was 14.75.

Clinical example.

Patient G., 55 years old (medical history No. 954), was admitted as an emergency to the surgical department of the city clinical hospital No. 7 of Ivanovo on 03/27/2004 with a diagnosis of acute calculous cholecystitis. At admission, pain in the right hypochondrium, which arose after an error in the diet, increased temperature to 38 ° C, was disturbed.

From the anamnesis: for several years he suffers from cholelithiasis (calculi in the gall bladder were detected by ultrasound); in 1994, a resection of the stomach was performed for peptic ulcer of the duodenum; about 25 years old suffers from chronic catarrhal bronchitis.

In the surgical department, preoperative preparation was performed: antispasmodic, anti-inflammatory, antibacterial therapy. Inflammation has decreased.

During the examination a day before the operation (04/07/2004): no complaints, satisfactory condition, clear consciousness; skin and mucous membranes of normal color, subcutaneous tissue is excessively developed (body weight 80 kg, height 157 cm, body mass index 32.5), no edema; vesicular breathing over the entire surface of the lungs, no wheezing, percussion-clear pulmonary sound, respiratory rate 18 per minute; heart sounds are muffled, blood pressure 130/80 mm RT. Art., pulse 84 beats. per minute, rhythmic; the abdomen is soft, painless in all departments. Data from laboratory research methods (general clinical analysis of blood and urine, biochemical parameters) are within normal limits. An X-ray examination of the chest organs revealed no pathology. On the ECG - sinus rhythm, the deviation of the electrical axis of the heart to the left. When assessing the function of external respiration, moderate mixed disorders were found with a predominance of restrictive (VC - 2400 ml - 80.3% of the due, FEV ₁ - 1700 ml - 71.5% of the due, VC / FEV ₁ = 70.8%, PIC - 3.8 l / s - 66.5% of the due; PDVD - 30 mm water column; PDVd - 60 mm water column).

04/08/2004 in a planned manner under combined general anesthesia performed cholecystectomy from the right hypochondrium. Surgery and anesthesia without complications. The first two days after the operation: clear consciousness, serious condition, complaints of pain in the area of the operation; skin and mucous membranes of normal color; no swelling; body temperature 37.0-37.5 °; vesicular breathing over the entire surface of the lungs, no wheezing, percussion-clear pulmonary sound, respiratory rate 19-22 per minute; heart sounds are muffled, blood pressure 130 / 80-140 / 90 mm RT. Art., pulse 88-92 beats. per minute, rhythmic; the abdomen is soft, painful in the area of operation. On the second day after the operation, the parameters of FVD were determined: VC - 1400 ml, FEV ₁ - 1000 ml, PDId - 30 mm of water. Art. By the fifth day after the operation, pain in the area of the operation was significantly reduced; a state of moderate severity; skin and mucous membranes of normal color; body temperature 37.0 °; respiratory rate 18-20 per minute, vesicular breathing over the entire surface of the lungs, no rales, percussion-clear pulmonary sound; heart sounds are muffled, blood pressure 130/80 mm RT. Art., pulse 88 beats. per minute, rhythmic; the abdomen is soft, moderately painful in the area of operation; postoperative wound without features. On the fifth day after the operation, the parameters of the FVD were determined: VC - 1700 ml, FEV ₁ - 1300 ml, PDId - 35 mm of water. Art.

A method for predicting pneumonia after surgery on the organs of the upper floor of the abdominal cavity is applied. VC on the 5th day after surgery amounted to 121.4% (<130%) of the value of 2 postoperative days, FEV ₁ on the 5th day after the operation amounted to 130% (> 125%) of the value of 2 postoperative days , PD on the 5th day after surgery was 116.7% (<130%) of the value of 2 postoperative days. Thus, the patient had two of the three prognostic signs. Forecast: high probability of developing postoperative pneumonia.

On the seventh day after the operation, the patient complained of deterioration of health, general weakness, unproductive cough; subfebrile temperature, skin and mucous membranes of normal color were noted; respiratory rate 21 per minute, vesicular breathing, weakened on the right in the lower parts, moist finely bubbling rales above the weakening zone, shortening of percussion sound; heart sounds are muffled, blood pressure 140/90 mm RT. Art., pulse 92 beats. per minute, rhythmic; the abdomen is soft, moderately painful in the area of operation; postoperative wound without features. An X-ray examination of the chest revealed infiltration in the lower lobe of the right lung. Diagnosed with right-sided lower lobe bronchopneumonia.

Thus, the forecast made by the method developed by us was justified.

Table 1
The results of evaluating the reliability of differences in the increase in the FVD indicators on the 5th day after the operation compared with the 2 days after the operation in patients of the main group and the comparison group (units of measure are the values of the FVD indicators on the 5th postoperative day, in% of the values 2 postoperative days) Indicator Main group Comparison group Assessment of significance of differences t P JELL 122.77 ± 2.18 138.87 ± 1.49 5.52 <0.001 FEV ₁ 109.03 ± 1.9 137.38 ± 1.04 13.21 <0.001 Dvd 119.82 ± 2.5 151.01 ± 2.58 6.48 <0.001

table 2
The boundaries of the reference intervals (units of measurement - the values of the parameters of the HPF on the 5th postoperative day, expressed in% of the values of 2 postoperative days) Indicator The boundaries of the reference intervals Main group Comparison group JELL 104.15-141.39 116.31-161.43 FEV ₁ 92.78-125.28 121.48-153.28 Dvd 98.48-141.16 114.83-187.19

Table 3
The frequency of cases with the values of the HPF indicators not exceeding the “separation point” in the main group and the comparison group; differences significance assessment results Indicator Main group Comparison group Difference Reliability Assessment Results Abs. qty Frequency (%) Abs. qty Frequency (%) t P JELL 13 68,42 6 10.17 5.12 0.001 FEV ₁ 19 one hundred 3 5.08 33.19 0.001 Dvd 17 89.47 7 11.86 9.46 0.001

Table 4
Frequency table Test result Postoperative pneumonia developed There was no pneumonia Total Positive (≥2 out of 3 signs) 19 four 23 Negative (<2 out of 3 signs) 0 55 55 Total 19 59

Claims (1)

A method for predicting pneumonia after surgical interventions on the organs of the upper floor of the abdominal cavity, comprising determining indicators of external respiration function, characterized in that the indicators are examined: vital capacity of the lungs and forced expiratory volume in the first second by spirometry and additional peak expiratory pressure by pneumonometry in the immediate postoperative period - on the 2nd and 5th day after the operation, and in the presence of any two of the three signs: the value of vital lung capacity on the 5th day after the operation does not exceed 130% of its value on the 2nd postoperative day, the value of forced expiratory volume in the first second on the 5th day after the operation does not exceed 125% of its value on the 2nd postoperative day, the peak expiratory pressure on the 5th day after surgery does not exceed 130% of its value on the 2nd postoperative day, they predict a high risk of pneumonia after surgery on the organs of the upper floor of the abdominal cavity.