This document discusses various methods of assessing outcomes following surgery. It begins by explaining the importance of measuring outcomes in a transparent and reproducible way. It then describes several common methods of assessing outcomes, including duration of hospital stay, mortality rates, ASA physical status classification, POSSUM scoring system, and the Clavien-Dindo classification of surgical complications. More recently, there is a shift toward also measuring patient-centered outcomes like physical activity and quality of life. The document also discusses enhanced recovery after surgery (ERAS) protocols, which aim to improve surgical outcomes through a multimodal approach including preoperative counseling and optimization, standardized anesthetic and analgesic regimens, and early postoperative mobilization.

1. Assessing Outcome
Following Surgery
Dr Sanish Manandhar
Resident (General Surgery)
Mentor: Prof. Dr Rupesh Mukhiya

2. Introduction
• Measuring outcome in a transparent and reproducible manner is
central for evaluation of surgical performance and perioperative care.
• Outcome measurements following surgery have traditionally focused
on objective data such as duration of hospital stay and mortality at 30
days.
• Recently, shift in measuring outcomes that are important to patients,
such as physical activity, cognition and general well-being.

3. Introduction
• Despite advances in surgical technique and peri-operative care, high-
risk surgical procedures still carry a significant risk
• The 48 hour and 30 day incidence of postoperative mortality was
0.57% and 2.1%, respectively
• In an attempt to quantify the risk of peri-operative morbidity and
mortality, a number of scoring systems have been developed
Fecho K, Lunney AT, Boysen PG, Rock P, Norfleet EA. Postoperative mortality after inpatient surgery: Incidence
and risk factors. Ther Clin Risk Manag. 2008;4(4):681-688. doi:10.2147/tcrm.s2735

4. ASA physical status classification system
• ASA-PS score shows good correlation with postoperative outcome for
patient populations in a number of surgical settings
• Physical Status classification may initially be determined at various
times during the preoperative assessment of the patient
• The final assignment of Physical Status classification is made on the
day of anesthesia care

5. ASA physical status classification system
ASA PS Classification Definition
ASA I A normal healthy patient
ASA II A patient with mild systemic disease
ASA III A patient with severe systemic disease
ASA IV A patient with severe systemic disease that is a
constant threat to life
ASA V A moribund patient who is not expected to survive
without the operation
ASA VI A declared brain-dead patient whose organs are being
removed for donor purposes

6. ASA physical status classification system
Examples

7. ASA physical status classification system
Examples

8. ASA physical status classification system
• Limitations
• does not describe individual patient risk
• cannot account for surgical procedure, preoperative optimisation
or individual differences in postoperative care setting
• poor ability to identify individuals likely to experience
complications in the postoperative period

9. POSSUM
• POSSUM (Physiological and Operative Severity Score for the
enUmeration of Mortality and morbidity)
• Used to help provide both retrospective and prospective analysis of
the risk of post-surgical mortality and morbidity.
• The POSSUM score describes 18 factors in two component parts; 12
physiological factors (PS) and 6 operative factors (OS).
• Each factor is scored exponentially increasing from 1 to 8 (1, 2, 4, 8)
dependent upon grading

10. POSSUM
• Physiological score
• Physiological variables are those apparent at the time of surgery and include
8 variables
• Include clinical symptoms and signs, results of simple biochemical and
hematological investigations, and electrocardiographic changes
• If a particular variable is not available, a score of 1 is allocated
• Some variables may be assessed by means of clinical symptoms or signs or by
means of changes on chest radiographic findings
• Operative score
• Operative severity part of the score includes 6 variables
• The number of operations indicates the chronology of the procedure(s) within
30 days

11. POSSUM
R1 = Mortality
R2 = Morbidity

12. POSSUM
The number of operations
indicates the chronology of the
procedure(s) within 30 days

13. Clavien-Dindo Classification (CDC)
• The basis of this classification - rank a complication in an objective
and reproducible manner
• Determining the outcome postoperatively
• Clavien–Dindo classification is now further developed into the
Comprehensive Complication Index (CCI)

14. Clavien-Dindo Classification (CDC)
Grade Definition
Grade I Any deviation from the normal postoperative course without the need for pharmacological
treatment or surgical, endoscopic and radiological interventions
Allowed therapeutic regimens are: drugs as antiemetics, antipyretics, analgetics, diuretics and
electrolytes and physiotherapy. This grade also includes wound infections opened at the bedside.
Grade II Requiring pharmacological treatment with drugs other than such allowed for grade I
complications.
Blood transfusions and total parenteral nutrition are also included.
Grade III Requiring surgical, endoscopic or radiological intervention
- IIIa
- IIIb
Intervention not under general anesthesia
Intervention under general anesthesia
Grade IV Life-threatening complication (including CNS complications - brain hemorrhage, ischemic stroke,
subarachnoidal bleeding, but excluding transient ischemic attacks (TIA)) requiring ICU-
management
- IVa
- IVb
Single organ dysfunction (including dialysis)
Multi organ dysfunction
Grade V Death of a patient

15. Comprehensive Complication Index (CCI)
• Clavien–Dindo classification is now further developed into the Comprehensive
Complication Index (CCI)
• It is a refined method to integrate all complications into one formula
representing the overall postoperative complication burden with a single
number.
• It summarizes overall patient burden, and furthermore, permits the
observation of complication trends over time.
• The end result of CCI calculation yields a continuous scale to rank the severity
of any combination from 0 (best) to 100 (death) in a single patient.

16. Comprehensive Complication Index (CCI)
Clavien-Dindo Classification (CDC) CCI
CCI Value wC
I 8.7 300
II 20.9 1750
IIIa 26.2 2750
IIIb 33.7 4550
IVa 42.4 7200
IVb 46.2 8550
V Always results in CCI score of 100

17. Improving outcomes
• An initial early direct surgical complication (wound dehiscence, major
bleeding, anastomotic leakage, etc.) may lead to an increased risk of
medical complications (pulmonary, cardiac, thromboembolic, etc.)
• Oppositely, an initial medical complication may lead to a higher risk of
a surgical complication

18. Improving outcomes
• All outcome measures may potentially be improved by including a
neglected area in perioperative medicine
• And with regard to a specific time course analysis of the quality of
postoperative complications
• Multidisciplinary ERAS programs have been documented to decrease
the risk of medical complications

19. ERAS protocal
• Enhanced recovery after surgery (ERAS) protocols are multimodal
perioperative care pathways designed to achieve early recovery after
surgical procedures by maintaining pre-operative organ function and
reducing the profound stress response following surgery.
• The fundamentals of ERAS is to improve the outcomes following the
surgery

20. ERAS protocol
• The key elements of ERAS protocols include
• preoperative counselling
• optimization of nutrition
• standardized analgesic and anesthetic regimens
• early mobilization

21. ERAS protocal - Preoperative
• Preadmission counselling
• Fluid and carbohydrate loading
• No prolonged fasting
• No/selective bowel preparation
• Antibiotic prophylaxis
• Thromboprophylaxis
• No premedication

23. ERAS protocal - Intraoperative
• Short-acting anesthetic agents
• Mid-thoracic epidural anesthesia/analgesia
• No drains
• Avoidance of salt and water overload
• Maintenance of normothermia (body warmer/ warm intravenous
fluids)

24. ERAS protocal - Postoperative
• Mid-thoracic epidural anesthesia/analgesia
• No nasogastric tubes
• Prevention of salt and water overload
• Early removal of catheter and drains
• Early oral nutrition
• Non-opioid oral analgesia/ NSAIDs
• Early mobilization
• Stimulation of gut motility
• Audit of compliance and outcomes

25. Conclusion:
In the most comprehensive meta-analysis of mechanical bowel preparation in elective colorectal
surgery to date, this study has suggested that the use of mechanical bowel preparation does not affect
the incidence of postoperative complications when compared with no preparation. Hence, mechanical
bowel preparation should not be administered routinely prior to elective colorectal surgery.

26. Conclusion:
The use of chewing gum after colorectal surgery is a safe and effective intervention
in reducing the incidence of POI and merits routine use alongside other ERAS
pathways in the postoperative setting.

27. References
• Kehlet H, Clavien PA. Surgical outcome assessment - the need for better and
standardized approaches?. Can J Anaesth. 2021;68(1):20-23.
doi:10.1007/s12630-020-01831-0
• Fecho K, Lunney AT, Boysen PG, Rock P, Norfleet EA. Postoperative mortality
after inpatient surgery: Incidence and risk factors. Ther Clin Risk Manag.
2008;4(4):681-688. doi:10.2147/tcrm.s2735
• Amr E. Abouleish, Marc L. Leib, Neal H. Cohen; ASA Provides Examples to Each
ASA Physical Status Class. ASA Newsletter. 2015; 79:38–49
• Copeland GP. The POSSUM System of Surgical Audit. Arch Surg.
2002;137(1):15–19. doi:10.1001/archsurg.137.1.15

28. References
• Melnyk M, Casey RG, Black P, Koupparis AJ. Enhanced recovery after
surgery (ERAS) protocols: Time to change practice?. Can Urol Assoc J.
2011;5(5):342-348. doi:10.5489/cuaj.11002
• Rollins KE, Javanmard-Emamghissi H, Lobo DN. Impact of mechanical
bowel preparation in elective colorectal surgery: A meta-analysis.
World J Gastroenterol. 2018;24(4):519-536.
doi:10.3748/wjg.v24.i4.519
• Roslan F, Kushairi A, Cappuyns L, Daliya P, Adiamah A. The Impact of
Sham Feeding with Chewing Gum on Postoperative Ileus Following
Colorectal Surgery: a Meta-Analysis of Randomised Controlled Trials. J
Gastrointest Surg. 2020;24(11):2643-2653. doi:10.1007/s11605-019-
04507-3

29. THANK YOU!!!