|Year : 2020 | Volume
| Issue : 3 | Page : 96-102
Spectrum of postoperative admissions in the intensive care unit of a tertiary care hospital: An Indian update
Vijay Singh1, Rashmi Datta2, Shibu Sasidharan1, Lalit Tomar2
1 Department of Anaesthesiology and Critical Care, Level III Indian Field Hospital, Goma, Democratic Republic of Congo
2 Department of Surgery, Level III Indian Field Hospital, Goma, Democratic Republic of Congo
|Date of Submission||11-May-2020|
|Date of Decision||15-Jun-2020|
|Date of Acceptance||20-Jul-2020|
|Date of Web Publication||30-Sep-2020|
Department of Anaesthesia and Critical Care, Level III UN Hospital, Goma
Democratic Republic of Congo
Source of Support: None, Conflict of Interest: None
Background: The allocation of intensive care unit (ICU) beds for postoperative patients is a difficult task because of expensive and limited resources. Hence, it is imperative that it requires stratification of patients who most deserve ICU admission. With this background, this study was conducted to do a prospective evaluation of postoperative admissions in the ICU over a period of 1 year to analyze the postoperative admissions to the ICU and to formulate recommendations based on limited resources. Aim: To analyze the postoperative admissions to the ICU and to formulate recommendations based on limited resources. Settings and Design: The study was done in a tertiary level teaching hospital in India, over a period of 1 year. All patients meeting the inclusion criteria admitted to the surgical ICU were analyzed in the study as per method designed. Materials and Methods: Postoperative patients were admitted to ICU into three groups: (1) planned, (2) unplanned, and (3) emergency. The study analyzed American Society of Anesthesiologists (ASA) status, preplanned postoperative ventilation, not reversed due to intraoperative complications (which included those patients who developed intraoperative complications and admitted to ICU for postoperative ventilation), postoperative observation (which included those patients who were admitted to ICU only for monitoring and didn't experience any anticipated perioperative complications) and others causes group. Statistical Analysis: All the statistical analyses were performed using SPSS version 20. Results: In 1 year, total patients operated were 18157 and 261 patients were admitted to ICU. In planned group, maximum patients were ASA III and in unplanned/emergency admissions ASA II. The common cause of postoperative ICU admission in the planned group was postoperative observation (58.80%; 124/211) and in unplanned/emergency group, it was other causes. Maximum patients admitted to ICU were of ASA III (59.40%; 155/261) and for postoperative observation 54.80% (85/155). Conclusions: The authors have a valuable consideration into our standards of anesthetic practice to improve the process of allocating ICU beds for postoperative patient.
Keywords: Anesthesia, critical care, intensive care unit
|How to cite this article:|
Singh V, Datta R, Sasidharan S, Tomar L. Spectrum of postoperative admissions in the intensive care unit of a tertiary care hospital: An Indian update. Saudi Crit Care J 2020;4:96-102
|How to cite this URL:|
Singh V, Datta R, Sasidharan S, Tomar L. Spectrum of postoperative admissions in the intensive care unit of a tertiary care hospital: An Indian update. Saudi Crit Care J [serial online] 2020 [cited 2020 Oct 31];4:96-102. Available from: https://www.sccj-sa.org/text.asp?2020/4/3/96/296835
| Introduction|| |
The intensive care unit (ICU) is a special unit primarily concerned with the care of patients with potentially recoverable critical illness. These patients will benefit from more detailed monitoring and invasive treatment than provided in general wards or high dependency areas., Patients should be admitted to ICU before their condition deteriorate to such an extent that recovery is impossible. However, ICU beds are variously scaled. In the United States, up to 20% of hospital beds are labeled as intensive care beds. In the United Kingdom, intensive care usually comprises only up to 2% of the total bed strength of a hospital. This high disparity is attributed to the United Kingdom policy of admitting only the most severely ill. Usually, in India, ICUs are scaled at 5%–8% of the total hospital beds; less than these are not considered economically viable.,, Due to limited ICU beds, obtaining a bed in ICU for critically ill patients is quite often difficult. Owing to scarcity of ICU beds, only the most critical patients are to be provided ICU care. Hence, there appears a strong need to admit patient in ICU who deserves most.
Outcome of high-risk general surgical patients could be improved by adequate provision and more effective utilization of critical care resources. However, there is a scarcity of evidence-based information about guidelines and standards for ICU triage after major surgery. The multifactorial interaction of patient, anesthesia, and surgical variables determine overall patient risk. Ideally, surgeons, anesthesiologists, and intensivists admitting surgical patients to ICUs target the patients who will benefit most from this highest level of postoperative care. However, accurately identifying which patients are at high risk of complications or death after major surgery remains difficult.,
The American Society of Anesthesiologists (ASA) physical status classification system is a scoring system commonly used in anesthesia to assess the severity of the comorbidities and indirectly the requirement of a postoperative period of observation in the ICU.,, Similarly, there are a number of surgical scoring systems to assess the degree of a patient's physical state prior and during the surgery to assess the requirement of critical observation following surgery.,,, The operative complexity is also a major factor necessitating ICU observation.
Appropriate decisions relating to the need for intensive care after surgery are keys for high-quality patient care, yet adequate systems for triage remain elusive. The potential exists for underuse of critical care resources, with inappropriate lack of admission to an ICU for high-risk patients, as well as overuse, with unnecessary admissions, leading to increased length of stay and costs.
The cost of caring for ICU patients is estimated to be three to five times more than conventional ward care. Hence, it is imperative that expensive and limited resources require stratification of patients into those who would benefit most from ICU admission and those who may derive less benefit. Even, patient affordability to access intensive care services becomes an important factor; therefore, relative attention should be directed to improving patient selection for ICU admission. Apart from our professional, moral, and ethical compulsions as care providers, it is very much essential that we deliver quality care cost efficiently. With this background, this study was undertaken to do a prospective evaluation of postoperative admissions in the ICU of a tertiary care hospital. We attempted to analyze the postoperative admissions to the ICU and to formulate recommendations based on limited resources in the ICU.
| Materials and Methods|| |
After the approval of Hospital Ethical Committee, all postoperative patients were divided into three groups:
- Group 1 – Planned admissions: This included those patients, where the surgeon and/or the anesthesiologist had decided preoperatively based on clinical profile of cases, anticipated intraoperative complications due to surgery/anesthesia, age, duration of surgery, and preexisting comorbidities that ICU admission would be required postoperative
- Group 2 – Unplanned admissions: This included those patients, whose admission were not anticipated preoperatively, but ICU care was required due to unexpected complications arising in the perioperative period. These complications could have occurred at any time in the operating theater room, within the postanesthesia care unit or <48 h after discharge from the postanesthesia care unit
- Group 3 – Emergency admissions: This includes those patients who were admitted to the ICU after 48 h of the primary surgery for postoperative complications.
For study, the following variables were analyzed
- ASA physical status classification system
- Preplanned postoperative ventilation (surgeon and/or the anesthesiologist had decided preoperatively for postoperative ventilation based on duration of surgery/anesthesia, clinical profile of patient, comorbidities, and other surgical and anesthesia factors)
- Not reversed due to intraoperative complications which included those patients who developed intraoperative complications so, admitted to ICU for postoperative ventilation
- Postoperative observation included those patients who were admitted to ICU only for monitoring and did not experience any anticipated perioperative complications
- Others causes group (included those patients who developed perioperative complications but no ventilation required in ICU).
- All surgical patients admitted to ICU from operating room who needed intensive observation, management, or monitoring in the postoperative period
- All patients who needed ICU care in view of unexpected perioperative complications
- All patients who were admitted to the ICU after 48 h of the primary surgery for postoperative complications.
- Patients already admitted to ICU for any other surgical/medical condition and who developed a surgical complication necessitating surgery
- Pediatric cases (<12 years of age) in view of separate ICU
- Cardiac cases as these are routinely admitted to ICU postoperatively.
The data of the patients were collected from all postoperative patients admitted in the ICU of a tertiary care hospital over a period of 1 year (March 1, 2018–March 1, 2019).
Sample size was calculated keeping in view at the most 5% risk, with minimum 80% power and 5% significance level (significant at 95% confidence level).
All the statistical analyses were performed using IBM Statistical Package for the Social Sciences (SPSS) version 20. Student's t-test was performed for comparison of quantitative variables. 5% probability level was considered as statistically significant, i.e., P < 0.05 was considered significant. Results were expressed as the means and standard deviations, numbers, and percentages. For quantitative independent sample, t-test was used to calculate mean and standard deviation.
| Observations and Results|| |
The study was conducted on 261 patients who were admitted in the ICU of a tertiary care hospital from the operating room over a period of 1 year.
During the 1 year period, the total listed cases in various OTs were 17617, cancelled cases 741, and unplanned or emergency cases were 1291. Emergency cases were mostly of gynecology and obstetrics, gastrointestinal surgery, neurosurgery, orthopedic surgery, and general surgery.
Based on ASA physical status of the postoperative patients admitted to the ICU, maximum patients belonged to ASA III with percentage 59.40% (155/261). In planned admissions also, maximum patients were ASA III with percentage 64.5% (136/211). However, in unplanned admissions and in emergency admissions, ASA II patients were predominant, 41.30% (19/46) and 50% (2/4), respectively. This was significant with P < 0.05 [Table 1].
|Table 1: Admission to intensive care unit (planned/unplanned/emergency)* based on American Society of Anesthesiologists physical status|
Click here to view
The predominant cause of postoperative ICU admission in planned group was for postoperative observation (58.80%; 124/211). However, in unplanned group, 71.7% (33/46) and emergency group 100% (4/4) - other causes were the predominant cause of ICU admission. (in unplanned group - Intra op complications and not ventilated postoperatively and in Emergency group - postoperative complications that developed after 48 h) [Table 2].
|Table 2: Admission intensive care unit (planned/unplanned/emergency)* causes of postoperative intensive care unit admission|
Click here to view
In planned group, preplanned postoperative ventilation was the cause of admission with 30.30% (64/211) and in unplanned group, 26.10% (12/46) patients were continued on ventilation in the ICU (patients not reversed due to intraoperative complications). This is statistically significant with P < 0.05.
According to ASA physical status, maximum patients admitted to ICU were of ASA III 59.40% (155/261) and the main cause of admission in ASA III was postoperative observation 54.80% (85/155). In ASA I patients, the main cause of ICU admission was other causes 37.50% (6/16) (intraoperative and postoperative complications but not ventilated), and in ASA II patients, the main cause of admission was again postoperative observation 46.80% (29/62). However, in ASA IV and ASA V patients, the main cause of ICU admission was pre-planned postoperative ventilation-63% (17/27) and 100% (1/1), respectively. This is significant with P < 0.05 [Table 3].
|Table 3: Admission to intensive care unit (planned/unplanned/emergency)* as per American Society of Anesthesiologists physical status|
Click here to view
[Table 4] describes the spectrum of cases who were admitted to the ICU. Maximum cases admitted were of GI surgery, followed by neurosurgery and orthopedic surgeries.
|Table 4: Admission to intensive care unit (planned/unplanned/emergency)* based on type of surgery|
Click here to view
[Table 5] describes the length of stay in ICU and postoperative admission. Maximum patients stayed for a duration of 2–4 days prior their discharge from ICU (38.70%) followed by 1–2 days.
|Table 5: Admission to intensive care unit (planned/unplanned/emergency)* VS. length of intensive care unit stay (<1 day/1-2 day/2-4 days/4-7 days/>7 days)|
Click here to view
| Discussion|| |
During the 1-year period, the total listed cases in operation theater were 17617, unplanned or emergency cases other than listed cases were 1291, and the cancelled cases 741, thus making a total number of operated cases in the period to be 18157. Out of this, a total of 261 postoperative cases were admitted to the ICU and making it a 1.43% incidence of postoperative ICU admissions. This figure was excluding pediatrics and cardiac surgery cases since there are separate ICUs in this institution and it is comparable to other studies.,,, However, Patel et al. had reported the incidence of postoperative admissions as 4.54%, but majority of their study population admitted to ICU were of ASA IV.
ASA physical status class is an assessment predictor based on physical status of the patients and has been linked with increased postoperative mortality , and perioperative complications , including increased ICU length of stay  and that is the reason for including in the present study as a variable to analyze. Regarding the preoperative ASA physical status of the postoperative patients admitted to the ICU, a substantial percentage of the patients (59.40%) were ASA III and which is similar to Lupei et al.'s study where they had find out that maximum postoperative patients admitted to ICU were of ASA III status. On further scrutiny, it was found out that planned ICU admissions were mostly in ASA III (64.50%), while in unplanned and emergency ICU admissions, ASA II were more (41.30%) and 50% respectively.
Some studies suggest that older patients with poor physical health are more likely to have unplanned ICU admissions., However, our findings do not support this hypothesis. In our study, the ASA physical status scores in the planned group were higher than those in the unplanned group. This difference could be because of prior anticipation and planning of admission to ICU in patients of higher ASA, like geriatric patients. In unplanned/emergency group, the admission were on the basis of complications. In virtually every study performed, the need to perform surgery on an emergency basis was associated with additional risk., In this study, 19.16% (50/261) of total postoperative ICU admissions were following emergency/unplanned surgeries and 80.84% of patients (211 out of 261 of total postoperative ICU admissions) were following planned surgeries, which is similar to Pearse et al.'s study (an European multicentric international study) where 3599 patients (8%) were admitted to ICU at some point during hospital stay, of them 2555 (71%) had planned admission.
The characteristics for the planned ICU admissions were not unexpected. In their preoperative assessment, anesthesiologists consider factors such as ASA physical status, preoperative medical illness, anticipated major blood loss, anticipated duration of anesthesia, anticipated mechanical ventilation, and airway problems when determining the need for postoperative ICU admission.,,, The present study did not permit to assess the correctness of these decisions. However, in this study, it was found that in planned group, 58.80% (124 out of 211) were admitted to ICU just for postoperative observation and monitoring, even though these patients did not experience any perioperative complications. This is comparable to a study by S Uzman et al. where they found 69.4% postoperative patients were low risk of those admitted to ICU for 1 day. However, it is different from some studies where incidence ranging from 20% to 40% for low-risk monitoring admission to the ICUs., However, this difference between the present study and the others could be due to the fact that this being a tertiary centre and teaching hospital, where safety and follow-up of postoperative cases is religiously done. Additionally, existing hospital policy mandates that all post neurosurgery cases have to be admitted to the ICU and that number would influence the statistics. However, it is also prudent to take the cost of ICU caring into consideration, which is substantial and estimated to be three to five times more than any other conventional ward care., Therefore, appropriate triage of patients to ICU postoperatively may be required by keeping in mind the limited ICU beds availability and resources, which may not be affordable in all health-care environments. Thus, the most appropriate use of this limited bed stock is very important. Clearly, it is neither possible nor desirable for every surgical patient to be admitted to critical care following surgery for postoperative observation. Surgeons and Anesthesiologists admitting surgical patients to ICUs need to stratify patients into those who would benefit most from this highest level of postoperative care and those who may derive less benefit. Definitive objective criteria to predict active treatment requirements and length of stay in the ICU need to be charted.,,,, Keeping these points in mind, some authors are in favor of creating an intermediate care facility or a separate room in ICU for low risk monitoring patients ,, for better and more efficient utilization of ICU resources. Even, it is suggested from us to admit patients into an acute care ward or high dependency unit (HDU) who requires only postoperative observation and provision should be laydown for shifting these patients immediately to ICU for specific interventions if they developed complications.
It is also brought to notice that there are no studies directly linking the incidence of postoperative observation of patients in ICU in planned group with ASA physical status. It was found that maximum patient belongs to ASA III and ASA II with 54.80% (85/155) and 46.80% (29/62) respectively, for postoperative observation. Additionally, we also found that in unplanned and emergency groups, maximum patients belonged to the other causes group (intraoperative or postoperative complications with no mechanical ventilation required in postoperative period) for ICU admission and their causes for admissions were hemodynamic instability (tachycardia, hypotension, hypertension, arrhythmia), postoperative oxygen de-saturation (SpO2 <90%), long duration of surgery, intraoperative major blood loss, pulmonary oedema and unanticipated difficult intubation. This can easily be explained by this fact that unanticipated complications had been occurred to unplanned and emergency group in perioperative period which could have led them to ICU admission for monitoring and intensive treatment. Else, these patients could have been discharged to home or sent to the surgical wards. Other than this, preplanned postoperative ventilation in planned group was 30.30% (64/211); however, there were no cases in unplanned/emergency group for preplanned postoperative ventilation. The reason for this is that, in preplanned postoperative ventilation for planned admission group, majority of patients had higher ASA status in comparison to unplanned/emergency group where majority of patients were from ASA I and ASA II. With respect to percentage, preplanned postoperative ventilation was maximum in ASA IV 63% (17/27) and ASA V 100% (1/1). It can be elucidated on the basis that these ASA IV and ASA V patients were in debilitated condition with multiple preexisting comorbidities; hence, keeping the safety of patient in mind, preplanned postoperative ventilation was mandatory. As this was a study of usual care, no attempt was made to influence the treating anesthesiologists about the choice of intra- or postoperative management.
| Conclusions|| |
There are no universal criteria for postoperative admission of the patients to the ICU. Hence, a detailed analysis of the reasons for postoperative admissions to the ICU needs to be elaborated to improve patient care. A combination of the following variables can be considered as predictive for postoperative ICU admission:
- Preplanned postoperative ventilation group
- Not reversed and ventilated postoperative due to intraoperative complication
- Other causes group (patients developed perioperative complication but not ventilated).
Those patients who would be kept in the ICU for postoperative observation can be admitted to acute care ward or HDU for monitoring and subsequently can be shifted to ICU as an when intensive care required. It is also imperative to mention that acute care ward or HDU should be in proximity to the ICU so that problem of shifting the patient to ICU can be tackled easily.
This assessment of postoperative ICU admissions in our study has provided us a valuable consideration into our standards of anesthetic practice and this will allow us a vision to change our current practice. Some studies show how it is possible to manage high risk patients without admission to ICU, and have made specific criteria for admission to ICU.,
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Smith G, Nielsen M. ABC of intensive care. Criteria for admission. BMJ 1999;318:1544-7.
Nathanson BH, Higgins TL, Kramer AA, Copes WS, Stark M, Teres D. Subgroup mortality probability models: Are they necessary for specialized intensive care units? Crit Care Med 2009;37:2375-86.
Jayaram R, Ramakrishnan N. Cost of intensive care in India. Indian J Crit Care Med 2008;12:55-61.
] [Full text]
Jhanji S, Thomas B, Ely A, Watson D, Hinds CJ, Pearse RM. Mortality and utilisation of critical care resources amongst high-risk surgical patients in a large NHS trust. Anaesthesia 2008;63:695-700.
Reich DL, Bennett-Guerrero E, Bodian CA, Hossain S, Winfree W, Krol M. Intraoperative tachycardia and hypertension are independently associated with adverse outcome in noncardiac surgery of long duration. Anesth Analg 2002;95:273-7.
Hartmann B, Junger A, Röhrig R, Klasen J, Jost A, Benson M, et al
. Intra-operative tachycardia and peri-operative outcome. Langenbeck's archives of surgery 2003;388:255-60.
Owens WD, Felts JA, Spitznagel EL Jr., ASA physical status classifications: A study of consistency of ratings. Anesthesiology 1978;49:239-43.
Wolters U, Wolf T, Stützer H, Schröder T. ASA classification and perioperative variables as predictors of postoperative outcome. Br J Anaesth 1996;77:217-22.
Dabbiss M. American Society of Anaesthesiologists physical status classification. Indian J Anaesth 2011;55:111-5.
Knaus WA, Zimmerman JE, Wagner DP, Draper EA, Lawrence DE. APACHE-acute physiology and chronic health evaluation: A physiologically based classification system. Crit Care Med 1981;9:591-7.
Copeland GP, Jones D, Walters M. POSSUM: A scoring system for surgical audit. Br J Surg 1991;78:355-60.
Gawande AA, Kwann MR, Regenbogen SE, Lipsitz SA, Zinner MJ. An apgar score for surgery. J Am Coll Surg 2007;204:201-8.
Turrentine FE, Wang H, Simpson VB, Jones RS. Surgical risk factors, morbidity, and mortality in elderly patients. J Am Coll Surg 2006;203:865-77.
Aust JB, Henderson W, Khuri S, Page CP. The impact of operative complexity on patient risk factors. Ann Surg 2005;241:1024-7.
Chandra A, Mangam S, Marzouk D. A review of risk scoring systems utilised in patients undergoing gastrointestinal surgery. J Gastrointest Surg 2009;13:1529-38.
Nightingale P, Denis E, Healy T, Cohen PJ. A Practice of Anaesthesia. London: J. Critical Care; 1996. p. 1309-45.
Satyawan AB, Shinde VS, Chaudhary LS. Audit of intensive care unit admissions from the operating room. Indian J Anaesth 2006;50:193-200.
Pearse RM, Moreno RP, Bauer P, Pelosi P, Metnitz P, Spies C, et al
. Mortality after surgery in Europe: a 7 day cohort study. The Lancet. 2012;380:1059-65.
Pearse RM, Harrison DA, James P, Watson D, Hinds C, Rhodes A, et al
. Identification and characterisation of the high-risk surgical population in the United Kingdom. Crit Care 2006;10:R81.
Ejiro BA, Endomwonyi NP. Audit of Intensive Care Unit (ICU) admissions from the operating room. JMBR: A Peer review. J Biomed Sci 2012;11:9-17.
Patel SK, Kacheriwala SM, Duttaroy DD. Audit of postoperative surgical intensive care unit admissions. Indian J Crit Care Med 2018;22:10-5.
] [Full text]
Dripps RD, Lamont A, Eckenhoff JE. The role of anesthesia in surgical mortality. JAMA 1961;178:261-6.
Vacanti CJ, VanHouten RJ, Hill RC. A statistical analysis of the relationship of physical status to postoperative mortality in 68,388 cases. Anesth Analg 1970;49:564-6.
Tiret L, Hatton F, Desmonts JM, Vourc'h G. Prediction of outcome of anaesthesia in patients over 40 years: A multifactorial risk index. Stat Med 1988;7:947-54.
Cohen MM, Duncan PG. Physical status score and trends in anesthetic complications. J Clin Epidemiol 1988;41:83-90.
Lupei MI, Chipman JG, Beilman GJ, Oancea SC, Konia MR. The association between ASA status and other risk stratification models on postoperative intensive care unit outcomes. Anesth Analg 2014;118:989-94.
Kim J, Kim YD, Lee DR, Kim KM, Lee WY, Lee S. Analysis of the characteristics of unplanned admission to the intensive care unit after general surgery. Anesthesia and Pain Medicine. 2019;14:230-5.
Quinn TD, Gabriel RA, Dutton RP, Urman RD. Analysis of unplanned postoperative admissions to the intensive care unit. J Intensive Care Med 2017;32:436-43.
Muravchick S. Anesthesia for the Elderly: Anesthesia. Philadelphia: Churchill Livingstone; 2000. p. 2140-56.
Koperna T, Semmler D, Marian F. Risk stratification in emergency surgical patients: Is the APACHE II score a reliable marker of physiological impairment? Arch Surg 2001;136:55-9.
Rose DK, Byrick RJ, Cohen MM, Caskennette GM. Planned and unplanned postoperative admissions to critical care for mechanical ventilation. Can J Anaesth 1996;43:333-40.
Uzman S, Yilmaz Y, Toptas M, Akkoc I, Gul YG, Daskaya H, Toptas Y. A retrospective analysis of postoperative patients admitted to the intensive care unit. Hippokratia. 2016;20:38.
Swann D, Houston P, Goldberg J. Audit of intensive care unit admissions from the operating room. Can J Anaesth 1993;40:137-41.
Du B, An Y, Kang Y, Yu X, Zhao M, Ma X, et al
. Characteristics of critically ill patients in ICUs in mainland China. Crit Care Med 2013;41:84-92.
Osinaike BB, Akinyemi OA, Sanusi AA. ICU utilization by cardio-thoracic patients in a Nigerian teaching hospital: Any role for HDU? Niger J Surg 2012;18:75-9.
] [Full text]
Okiror L, Patel N, Kho P, Ladas G, Dusmet M, Jordan S, et al
. Predicting risk of intensive care unit admission after resection for non-small cell lung cancer: A validation study. Interact Cardiovasc Thorac Surg 2012;14:31-3.
Teli M, Morris-Stiff G, Rees JR, Woodsford PV, Lewis MH. Vascular surgery, ICU and HDU: A 14-year observational study. Ann R Coll Surg Engl 2008;90:291-6.
Dahm P, Tuttle-Newhall JE, Nimjee SM, Byrne RR, Yowell CW, Price DT. Indications for admission to the surgical intensive care unit after radical cystectomy and urinary diversion. J Urol 2001;166:189-93.
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]