A prospective study of outcome of acute physiology and chronic health evaluation ii score in critically ill surgical patients

Rambir Singh; Rambabu Meena; Manish Khokad

doi:10.4103/AIHB.AIHB_43_16

ORIGINAL ARTICLE

Year : 2017 | Volume : 7 | Issue : 2 | Page : 61-64

A prospective study of outcome of acute physiology and chronic health evaluation ii score in critically ill surgical patients

Rambir Singh¹, Rambabu Meena², Manish Khokad³
¹ General Surgery, Dist. Hospital, Dausa, Rajasthan, India
² Department of Surgery, S.P. Medical College, Bikaner, Rajasthan, India
³ General Surgery, Community Health Centre, Mahwa, Rajasthan, India

Date of Web Publication

28-Apr-2017

Correspondence Address:
Rambabu Meena
Department of General Surgery, S.P. Medical College, Bikaner, Rajasthan
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/AIHB.AIHB_43_16

Abstract

Background: The acute physiology score is determined from the most deranged (worst) physiologic value, for example, the lowest blood pressure or the highest respiratory rate, during the initial 24 h after Intensive Care Unit (ICU) admission. The aim of present study is to apply Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system to surgical patients who have been critically ill preoperatively requiring elective surgical intervention or who underwent extensive elective surgery thereby requiring post-operative critical care monitoring and treatment in the post-operative ward or ICU or surgical ward. Materials and Methods: This prospective study was carried out on critically ill surgical patients from August 2012 to December 2013 in M. G. Hospital, Department of Surgery attached to Dr. S.N. Medical College and Associated Group of Hospitals, Jodhpur. The APACHE II score in the first 24 h of admission or operation and expected risks of death was calculated. Results: This study observed that 67.74% recovered male and 81.58% female and mortality rate increase when APACHE II score of patients increases. From the 100 patients enrolled the mean age was 47.38 ± 18.37 the overall median APACHE II score for all critically ill surgical patient was 9 with a range of 2–44 (minimum 2 and maximum 44). There was a significant difference between the APACHE II score of survivors and non-survivors. Conclusion: This scoring still provides a basic idea and uniform comparison of critical patients, thus help in research activities database validation. Few pitfalls related in the present study could have been avoided had there been large number of cases and more so of specific procedure-related patients necessitating critical care.

Keywords: Acute Physiology and Chronic Health Evaluation, critical care, Intensive Care Unit, mortality

How to cite this article:
Singh R, Meena R, Khokad M. A prospective study of outcome of acute physiology and chronic health evaluation ii score in critically ill surgical patients. Adv Hum Biol 2017;7:61-4

How to cite this URL:
Singh R, Meena R, Khokad M. A prospective study of outcome of acute physiology and chronic health evaluation ii score in critically ill surgical patients. Adv Hum Biol [serial online] 2017 [cited 2023 Mar 27];7:61-4. Available from: https://www.aihbonline.com/text.asp?2017/7/2/61/205395

Introduction

The basis for Acute Physiology and Chronic Health Evaluations (APACHE's) development was the hypothesis that the severity of acute disease can be measured by quantifying the degree of abnormality of multiple physiologic variables. One of intensive care's major functions is to detect and treat life-threatening acute physiologic derangements and that a severity classification system must be based on objective physiologic measurements and be as independent of therapy as possible.^[1] Finally, the index should be valid for a wide range of diagnoses, easy to use and based on data available in most hospitals.^[2]

The acute physiology score (APS) is determined from the most deranged (worst) physiologic value, for example, the lowest blood pressure or the highest respiratory rate, during the initial 24 h after Intensive Care Unit (ICU) admission. The 24 h period ensures that all pertinent physiologic values are available, and clinical judgement ensures that each value is legitimate. Because severe chronic disease significantly reduces the probability of survival during acute illness, the original APACHE system incorporates a four-letter (A, B, C and D) designation corresponding to a spectrum ranging from excellent health (A) to severe chronic organ system insufficiency (D).^[2]

APACHE is a reliable and useful means of classifying ICU patients. Increases in APS are associated with increased risk of subsequent hospital death.^[2] APACHE has also proved useful in evaluating outcome from intensive care and in comparing the success of different treatment programmes.^[3],[4] However, the original APACHE system is complex and needed formal multi-institutional validation.^[5] The APACHE II system is the result of efforts to simplify and present a more clinically useful yet statistically accurate and valid patient classification system.

The weights for the nine remaining physiologic variables used in APCHE II are the same as in the original APCHE system. The recorded value is still based on the most deranged reading during each patient's initial 24 h in an ICU. Unlike APACHE, however, measurement of all 12 physiologic values is mandatory when using APCHE II. This eliminates the problem of missing values and concerns about the assumption that an unmeasured variable was normal.^[5],[6] Although arterial blood gas measurements may be inappropriate for some patients, exclusion of these values is not encouraged and should only be done when clinical judgement strongly suggests the results would be within normal limits.

Because age and severe chronic health problems reflect diminished physiologic reserve, they have been directly incorporated into APCHE II. Chronologic age is a well-documented risk factor for death from acute illness, that is independent of the severity of disease.^[7],[8] The weights assigned to age in APACHE II are based on their relative impact within this validation.

We discovered that when we controlled for acute physiologic derangement and age, three of the four chronic health classifications (B, C and D) were associated with higher death rates. However, only the most severe chronic organ system insufficiency or immunocompromised state (class D) markedly influenced outcome.^[7] We also discovered that non-operative and emergency surgery admissions had a substantially higher risk for death from their prior organ system insufficiency than elective surgical admissions (Surgery or post-operative patients are those admitted to the ICU directly from the operating or recovery room. All others are non-operative). This was probably because patients with the most severe chronic conditions are not considered to be candidates for elective surgery. Therefore, non-operative or emergency operative admissions with a severe chronic organ system dysfunction are given an additional 5 points, while similar elective surgical admissions are only given 2 points.

The aim of present study is to apply APACHE II scoring system to surgical patients who have been critically ill preoperatively requiring elective surgical intervention or who underwent extensive elective surgery thereby requiring post-operative critical care monitoring and treatment in the post-operative ward or ICU or surgical ward.

Materials and Methods

This prospective study was carried out on critically ill surgical patients from August 2012 to December 2013 in M. G. Hospital, Department of Surgery attached to Dr. S.N. Medical College and Associated Group of Hospitals, Jodhpur.

Inclusion criteria

Emergency surgical procedures

Perforation peritonitis
Appendicular peritonitis
SAIO, etc.

High-risk patients

Heart rate >110
Glasgow Coma Scale <13
Total leukocyte count >11,000/mm ³.

Elective major surgical procedures

Whipple's/triple bypass surgery
Esophagectomy
Low anterior resection.

Major surgical illness

Pancreatitis
Fournier's gangrene
Blunt trauma.

Some of these patients underwent emergency surgery.

Patients of both sexes were included.

Exclusion criteria

Patient <16 years of age
Patient with coronary artery bypass graft surgery
Burn patient.

The APACHE II score in the first 24 h of admission or operation and expected risks of death was calculated. [Table 1]

Table 1: Interpretation of score

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Validity was tested by analysing the accuracy of the predicted probabilities overall and within various APACHE score groups compared with observed mortalities using the Chi-square test and linear regression techniques. The comparison was reported statically significant at P < 0.05.

Results

The present study showed that the maximum number of patients was ≤44 years of age [Table 2]. Most of the patient in the present study belongs to APCHE II score 5–8 and least number of patients belongs to 29–32 APACHE II score [Table 3].

Table 2: Age wise sex distribution

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Table 3: Acute Physiology and Chronic Health Evaluation II score distribution

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This study observed that 67.74% recovered male and 81.58% female [Table 4] and mortality rate increase when APACHE II score of patients increases [Table 5]. From the 100 patients enrolled the mean age was 47.38 ± 18.37 the overall median APACHE II score for all critically ill surgical patient was 9 with a range of 2–44 (minimum 2 and maximum 44). There was a significant difference between the APACHE II score of survivors and non-survivors [Table 6].

Table 4: Final outcome

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Table 5: Mortality rate

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Table 6: Comparison between survivors and non-survivors

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Discussion

The disparity between demands and available health-care resources is a universal problem and ICU is an area where this disparity exists up to the maximum, especially in developing countries like India. When it comes to treatment, patients can generally be divided into three groups, who will benefit, those likely to benefit and those who will not. The relative size of these three groups will depend on the selection criteria used in the assessment. By not treating patients in ICU, who will not benefit, cost-effectiveness is increased in addition to avoiding a vegetative life.

At present various scoring systems are used to predict outcome in critically ill patients: Although all lack 100% accuracy but play a vital role in audit of ICU performance and clinical research. The present study was conducted in a government College Hospital, for validation of APACHE II scoring system by prospective study, for defining outcome in 100 critically ill surgical patients.

The ability to survive an acute illness is related to a patient's condition before he or she becomes acutely ill, which can be judged by the patient's age, sex and APS or any chronic health disease. In the present study, it was found that there was no apparent correlation between age or sex and mortality; even in elderly patients, the response to surgery and treatment if instituted timely was not different from young ones. Lee et al.^[9] had also reported fair outcome in elderly comparable to their younger counterparts in an analysis of Surgical ICU patients. This is in contrast to the general belief that advanced chronological age is associated with poor recovery from acute illness. The decrease in physiological function of many major organ systems that accompanies ageing may sometimes adversely affect the outcome. Mortality rate was unaffected by sex as well.

The APACHE II scoring system has been successfully used for prediction of outcome in majority of ICU patients by Knaus et al.,^[10] Wagner et al. (1983),^[7] Jordan et al.,^[11] Purdie et al.,^[12] Marks et al. (1991),^[13] Brown et al.,^[14] Van Le et al.,^[15] Wang et al.,^[16] Markgraf et al.^[17] However, these trails are from western developed countries, where medical facilities, technical expertise, availability of funds and the facilities for research are at an optimal level. The present prospective study of 100 critically ill post-operative ICU patients showed a significant correlation between the APACHE II scores and prognosis. On applying the Chi-square test, the difference in survival score and non-survivor score was found to be statistically significant.

In calculating sensitivity (accuracy of prediction of non-survivors), death was selected as the 'outcome positive' and score greater or equal to 17 was taken as test positive. The sensitivity was calculated to be 77.78% while specificity was 93.15%. The cut-off value of APACHE II score was taken as 17 because it was found to offer the optimal values in terms of both sensitivity and specificity. Ridley et al.^[18] had taken cut-off value as 20, Wang et al.^[16] had taken 15. In the present study, the mean APCHE II scores for survivor and non-survivors was 8.41 and 23.37 respectively whereas Giangiuliani et al.^[19] reported similar figures of 14.2 and 22.4, respectively. The observed mortality as per APACHE II score grading was highest in 21–30 range and lowest in 11–20 range (50%). Knaus et al.^[9] proposed predicted mortality as (0–10) =0%, (11–20) =27.5%, (21–30) =64%, (31–40) =89% and >40 = 100%. The observed mortality rate in comparison in the present study was (0–10) =1.64%, (11–20) =50%, (21–30) =91.67% (31–40) =75%, >40 = 100%. The reason for higher observed mortality in the present study in relation to APACHE II score grading is probably delayed hospitalisation, lack of proper transport facilities and limited resources.

Conclusion

This scoring still provides a basic idea and uniform comparison of critical patients, thus help in research activities database validation. Few pitfalls related in the present study could have been avoided had there been large number of cases and more so of specific procedure related patients necessitating critical care.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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