Assessment of adherence to preoperative fasting guidelines and associated patient discomfort in adult elective surgical patients in public hospitals of Addis Ababa, Ethiopia: a multicenter cross-sectional study : IJS Short Reports

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Assessment of adherence to preoperative fasting guidelines and associated patient discomfort in adult elective surgical patients in public hospitals of Addis Ababa, Ethiopia: a multicenter cross-sectional study

Fekede, Mulualem S. MSc*; Abebe, Bereket A. MSc; Awol, Meron A. MSc

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IJS: Short Reports: October/December 2022 - Volume 7 - Issue 4 - p e60
doi: 10.1097/SR9.0000000000000060
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Nothing by mouth (NPO) from midnight is a universal fasting policy before surgery which is easy to prescribe, and easily taken by staff and patients1. Preoperative fasting is a prescribed time before a procedure, restricting patients from oral intake of liquids or solids, to decrease gastric volume and to lower the risk of pulmonary aspiration during anesthesia2. For elective surgical patients of all age, a minimum of 2 hours of fasting for clear liquids, 4 hours for breast milk, and 6–8 hours for non–human milk and solid foods is recommended before anesthesia2–4.

Preoperative fasting instructions should be clear including the aim, duration, and expectations as well as the outcome of nonadherence5. The concern of pulmonary aspiration and the idea of fasting for long period safer for the patient led to unnecessary preoperative food and fluid restriction despite no scientific reasons to keep a patient in prolonged preoperative fasting6. Prolonged preoperative fasting before elective surgery causes patient discomfort7, affects preoperative thirst8–10, causes hunger and anxiety8,10, postoperative pain8,10, nausea and vomiting8,11.

Drinking oral clear fluids (such as water, pulp-free juice, and tea) up to 2 hours before elective surgery doesn’t increase the risk of aspiration, or related morbidity compared with the NPO after midnight fasting in healthy adults scheduled for elective surgery8,9,12–14. Intake of clear fluids 2 hours before surgery and anesthesia is recently recommended and encouraged, preventing not only dehydration but also improving patient satisfaction and well-being2–4,14.

However, NPO after midnight instruction is a common practice instead of individualized fasting instructions for clear liquids and solids1,14. In addition, preoperative fasting policies are different in different countries and hospitals, and patient comfort is neglected15. Due to this fixed NPO instruction, and rapidly changing surgical schedules, the absence of a formal fasting policy or staff’s inadequate knowledge of the policy14, patients fasted for unnecessary long periods than recommended before elective surgery affecting patients’ comfort and perioperative outcome16–18.

At Addis Ababa public hospitals, the preoperative fasting period is practiced from midnight without considering the time of the procedure and the order of the operation list. Knowing preoperative fasting duration and factors contributing for patients discomfort due to prolonged fasting will guide us to improve our clinical intervention and to improve patient comfort, satisfaction, and perioperative patients’ outcome. It will also help us to establish a formal fasting policy in accordance with current fasting guidelines. So, this study aimed to assess adherence to preoperative fasting guidelines and associated patient discomfort in adult patients undergoing elective surgery in public hospitals of Addis Ababa.

Materials and methods

Study design, setting, and patients

This multicenter hospital-based cross-sectional study was conducted from February 20, to May 10, 2021, in 5 public hospitals of Addis Ababa: Tikur Anbessa Specialized Hospital (TASH), Saint Paul’s Hospital Millennium Medical College (SPHMMC), Zewditu Memorial Hospital, Ras Desta Hospital, and Menelik II Hospital. These hospitals had been chosen purposely because they are tertiary referral hospitals rendering major surgical and other services for patients from all over the country in different departments.

The source population was all adult patients above 18 years who underwent elective surgery in public hospitals of Addis Ababa, and the study population was adult patients who underwent elective surgery at selected public hospitals of Addis Ababa and selected for the sample. American Society of Anesthesiologists (ASA) I and II adult patients above 18 years who underwent elective surgery were included in this study. Adult patients with conditions that can affect gastric emptying or fluid volume (eg, pregnant women, obesity, gastroesophageal reflux disease, hiatus hernia, bowel obstruction, enteral tube feeding), and patients who were coming for emergency surgery were excluded.

This study has been registered on the Research Registry and has got a UIN “researchregistry7343” which can be accessed through This research has been reported in line with the STROCSS criteria 202119.

Sample size and sampling procedure

The sample size was determined using the single population proportion formula by assuming the prevalence as 0.5 and 5% margin of error at 95% CI. Then, by adding a 10% nonresponse rate; a total of 422 participants were participated in this study.

The sample size for each selected hospital was obtained by proportional allocation. Based on the log book review, 1550 elective surgeries were performed per 3 months on the study hospitals (Fig. 1). Study participants were selected using a systematic random sampling technique using sampling interval (K): K=N/n; 1550/422≈4. Therefore, the first study participant was selected using lottery method from each surgical specialty on daily basis in each hospital. Then, every fourth cases from the daily surgical procedures from each surgical specialty were included during the study period.

Figure 1:
Enrollment chart of patients’ undergoing elective surgery in selected public hospitals, Addis Ababa, Ethiopia, 2021. SPHMMC indicates Saint Paul’s Hospital Millennium Medical College; TASH, Tikur Anbessa Specialized Hospital.

Data collection procedures

Ethical approval was obtained from the Institutional Review Board (IRB) of School of Medicine, College of Health Sciences, Addis Abba University to conduct this study. Then, a legal letter was submitted to the study hospital’s director explaining the purpose of the study. Data collection begun after getting an ethical clearance from each hospital. Data were collected by trained anesthetists from the patient and medical records after getting verbal informed consent from patients using a structured pretested questionnaire. Data collectors reviewed the patient’s chart, documented sociodemographic characteristics, source of preoperative fasting instructions, fasting instructions given, reasons for preoperative fasting, the order of the operation schedule, time of the last meal and drink, and patients discomfort due to preoperative fasting in reception area before they entered to the operation room.

Data processing and analysis

Data were checked, coded, and entered to SPSS, version 24 (IBM corporate) for analysis. The data were tested for normality of distribution using the Shapiro-Wilk normality test, skewness and kurtosis, and histogram. Continuous variables were expressed as mean and SD. Categorical variables were summarized by percentages. The Spearman correlation was used to assess associations between total fasting time and independent variables as well as discomforting factors. An independent t test was used to compare the mean fasting time between operations before and after mid-day. A P value ≤0.05 was considered as statistically significant.

Operational definition(s)

  • Discomfort: a feeling of uncomfortableness experienced or perceived by patients due to preoperative fasting (eg, thirst, hunger, mouth dryness, tiredness).
  • Preoperative fasting time: time in hours from the last meal taken by the patient to the time of the initiation of the anesthetic procedure.
  • Prolonged fasting: when patients fasted from both food and fluid longer than the fasting time recommended by the ASA, Royal College of Nursing, and European Society of Anesthesiologists fasting guidelines2–4.


Demographic and preoperative characteristics of study participants

A total of 422 adult patients scheduled for elective surgery were included in this study with a 100% response rate. The mean age of participants was 40.8±14.3 years (range: 18–75 y). More than half (53.1%) of the participants were female, and 256 (60.7%) had no known comorbidities (Table 1).

Table 1 - Demographic characteristics of participant at selected public hospitals of Addis Ababa, Ethiopia, 2021.
Characteristics n (%)
 Female 224 (53.1)
 Male 198 (46.9)
ASA classification
 I 256 (60.7)
 II 166 (39.3)
 No formal education 113 (26.8)
 Primary school 130 (30.8)
 Secondary school 108 (25.6)
 College/university 71 (16.8)
ASA indicates American Society of Anesthesiologists.

Anesthesia and surgery-related characteristics of study participants

Regarding type of anesthesia, 60.2% of patients underwent surgery under general anesthesia, and the rest under spinal anesthesia. Among the various types of surgical procedures performed in this study, 190 (45%) participants underwent general surgery followed by urology; 85 (20.1%) (Fig. 2).

Figure 2:
Types of surgeries performed among participants at selected public hospitals of Addis Ababa, Ethiopia, 2021.

Source of preoperative fasting instructions

The majority (97.4%) of patients were instructed to abstain from both liquids and solids from midnight. More than half (57.3%) of patients were given preoperative fasting instruction by ward nurses, followed by interns (23.2%), surgeons (10%), and anesthetists (9.5%). The correct instruction was given for 156 (37%) of the participants, for those patients who were scheduled as 1st in the early morning for solid food, but only 8 (5%) participants followed the prescribed time.

Awareness of participants on preoperative fasting

Regarding patients’ knowledge on reason for preoperative fasting, only 5 participants (1.2%) gave the correct reason, namely, to prevent regurgitation and aspiration. The majority of participants (63.4%) didn’t know the reason of preoperative fasting; while others said the requirement of surgery (29.4%), preventing surgical bleeding (4.3%), and to reduce sugar level during surgery (1.7%).

Adherence to preoperative fasting time for food and fluid

Majority (98.1%) of the participants were operated after 8 hours of fasting for both food and fluids, and from those, 78% (n=329) operated after >12 hours of fasting. Only 8 (1.9%) participants were fasting as per the recommended international preoperative fasting guidelines for solid foods, while none of the participants did adhere to the guidelines for clear liquids. The mean preoperative fasting times were 13.89±2.37 hours for clear fluids and 14.26±2.35 hours for solids (Table 2).

Table 2 - Preoperative fasting time on the adherence to fasting guidelines in selected public hospitals, Addis Ababa, Ethiopia, 2021.
Variables Categories n (%) Total [n (%)]
Preoperative fasting hours Clear liquids ≤2 h 0 (0) 0 (0)
Liquids and solid foods ≤8 h 8 (1.9) 8 (1.9)
>8-12 h 85 (20.14) 414 (98.1)
>12 h 329 (77.96)
Mean fasting time [mean±SD (range)] (h) Clear liquids 13.89±2.37 (8–21)
Solid foods 14.26±2.35 (8–22)

Comparing the preoperative fasting time among study participants

An independent t test showed that there was a statically significant difference in the mean duration of liquid fasting for participants operated before mid-day (12.63±1.88 h) and after mid-day (15.81±1.65 h) (P<0.001). Likewise, there was a significant difference in the mean duration of solid fasting for participants operated before and after mid-day (P<0.001) (Table 3).

Table 3 - The mean fasting time difference between participants operated before and after mid-day at selected public hospitals of Addis Ababa, Ethiopia, 2021.
Preoperative Fasting Time in Hour Mean±SD P
Time of operation 12.63±1.88 <0.001*
For clear fluids
 Before mid-day
 After mid-day 15.81±1.65 <0.001*
For solid foods
 Before mid-day 13.04±1.84 <0.001*
 After mid-day 16.1±1.77 <0.001*
*Statistically significant in the independent t test (P<0.05).

Preoperative discomfort among the study participants

More than half (64%) of the participants felt discomfort during the preoperative period, and the discomforting factors were thirst (58.1%), hunger (49%), mouth dryness (49.8%), lengthy wait of prior surgery (16.4%), headache (22%), and tiredness (38.6%). In ascending order of their severity, the discomforting factors were grouped into none, mild, moderate, and severe (Fig. 3).

Figure 3:
Severity of preoperative discomfort among study participants at selected public hospitals, Addis Ababa, Ethiopia, 2021.

Sequence of schedule and reasons for delaying of surgery

Among 422 participants, 156 (37%) were scheduled as first, 160 (37.9%) as second, 79 (18.7%) as third, and 27 (6.4%) as fourth case. However, 181 (42.9%) of the surgeries were done based on the sequence of the schedule.

In this study, surgeries were delayed due to prior procedures took longer times in 92 (21.8%), changing sequence of schedule in the morning in 65 (15.4%), waiting for COVID-19 result in 47 (11.13%), delaying of starting time of surgery (5.7%), incorrect schedule given (1.42%), shortage of operation table (0.95%), and fumigation day (0.7%) of participants.

Factors correlated with preoperative fasting time

A Spearman rank-order correlation showed a correlation between total fasting time and level of education, sequence of schedule, and discomforting factors (thirst, hunger, mouth dryness, headache, and tiredness).

There was a statistically significant, strong positive correlation between solid, and liquid fasting time and the sequence of the patient’s schedule [rs (420)=0 .51, P<0.001], [rs (420)=0 .57, P<0.001]; respectively. There was also a statistically significant, moderate positive correlation between preoperative solid fasting time and level of hunger [rs (420)=0.37, P<0.001], thirst [rs (420)=0.46, P<0.001], and mouth dryness [rs (420)=0.32, P<0.001] (Table 4).

Table 4 - A correlation of preoperative fasting duration with predictors and discomforting factors among study participants.
Solid Fasting Duration Fluid Fasting Duration
Variables r s P r s P
Age 0.09 0.85 −0.01 0.82
Level of education −0.16* 0.001 −0.17* <0.001
Sequence of patient’s schedule 0.51* <0.001 0.57* <0.001
Thirst 0.46* <0.001 0.44* <0.001
Hunger 0.37* <0.001 0.34* <0.001
Dry mouth 0.32* <0.001 0.36* <0.001
Headache 0.11* 0.03 0.16* 0.001
Tiredness 0.22* <0.001 0.26* <0.001
*Correlation is significant at 0.05 level (2-tailed).
rs indicates Spearman rank-order correlation coefficient.


Our study showed that the majority (97.4%) of patients had prolonged NPO instructions for both liquids and solids regardless of the schedule of the procedure, despite evidences suggest that liquids have a fast gastric emptying than solids and recommended for a minimum of 2 hours fasting with no risk of aspiration2,12–14, and preoperative fasting instructions should be individualized and clear including the aim, duration, and the outcome of nonadherence5. Our result is comparable with a study done by Abebe et al20, which revealed that 98.1% of patients were instructed to fast from midnight.

We found that the mean fasting time for liquids and solids was higher than the recommended by ASA, Royal College of Nursing, and European Society of Anesthesiologists, with mean preoperative fasting time of 14.26±2.35 hours for solids, and 13.89±2.37 hours for fluids. The mean fasting time was 6.95 times longer for clear liquid and 2.38 times for solids than the ASA recommendation. Our finding is comparable with a study conducted in Turkey15. In contrary to our finding, a study done in Botswana found a higher fasting period for liquids18, while a study done in Turkey found lower duration of fasting time16. The difference could be due to the difference in the sample size, the absence of established formal fasting policy, and NPO after midnight instruction in our setup.

Our study also showed that there was a strong positive correlation between the sequence of the patient’s schedule and preoperative fasting time. Our result is supported by a study done in Sri Lanka which found changing surgical schedules contributed to longer preoperative fasting21.

The absence of individualized fasting prescription is the main contributing factor for prolonged preoperative fasting17, and patient education about the importance of preoperative fasting improves adherence to fasting instruction14. In our study, the duration of fast instruction for solids and clear liquids before surgery was not delivered clearly and the majority of patients lacked knowledge on the rationale for preoperative fasting. Our finding is supported by an audit in Ethiopia which found the implementation of fasting guidelines lacks a fasting protocol, lack of knowledge about the benefits of adherence to fasting protocol, and the adverse effect of prolonged fasting22. Our finding is also supported by an audit in Singapore23.

Our study also demonstrated that preoperative fasting was prolonged in more than half (57.1%) of participants due to incorrect orders of instructions, changing sequences of schedule with inadequate information delivery, prior procedures took longer times, waiting for COVID-19 result, and delay in the starting time of surgery without adjusting the fasting time. Therefore, good communication between nurses, surgeons, and anesthetists are needed to reduce the fasting time when surgery is delayed or postponed15,22,24.

Prolonged preoperative fasting causes discomfort and is known to have harmful effects7, and it also triggers a metabolic response that precipitates gluconeogenesis and increases the organic response to trauma12. In our study, more than half (64%) of patients felt preoperative discomfort, and factors contributing were thirst, hunger, mouth dryness, lengthy wait before surgery, and headache. Therefore, if nothing else to be taken by mouth, water is a good first step in preventing dehydration, improving patient satisfaction, lessening hunger and thirst, and for better hemodynamic stability8. Our result is comparable with studies performed by Gunawardhana and colleagues21,22,25. Our study result is also congruent with a study performed in Kenya5.

We also found a moderate positive correlation between preoperative fasting duration with hunger, thirst, and mouth dryness. Contrary to our study, a study in Turkey found preoperative thirst, hunger, and mouth dryness were weakly associated with total fasting time25. The differences could be due to correlation coefficient interpretation.

Our result also showed that level of education had a weak and negative correlation with preoperative fasting time. Patient’s level of education may help them to adhere with the fasting instruction and patient knowledge level is an indicator of the quality of interventions5.

Significant correlations could not be determined between the duration of fasting and participants age in our study. A study in Brazil revealed prolonged fasting was not associated with physical status, age, sex, and type of surgery24.

Limitations of the study

The effects of preoperative fasting were assessed by subjective patient’s self-reports instead of objective measures, and due to COVID-19 pandemic number of patients operated per day was decreased which limits the assessment of fasting time in patients scheduled for late afternoon. In addition, the effect of prolonged preoperative fasting was not assessed in patients with comorbidities such as, in patients with diabetes mellitus, and hypertension. Therefore, the results of this study finding should be interpreted carefully, and we recommend further study with a strong study design and statistical analysis.

Strength of the study

We have conducted a multicenter study with large sample size.

Conclusion and recommendation

Preoperative fasting duration for both solid foods and clear liquids was significantly longer than the recently recommended international fasting guidelines in public hospitals of Addis Ababa, Ethiopia. Preoperative fasting duration had an association with the sequence of patient schedules, the educational background of patients, and preoperative discomforting factors.

NPO instructions should be individualized based on the recommended preoperative fasting guidelines. The sequence of patient schedules and incorrect orders of instructions delivered challenged prolonged fasting experiences. Health professionals need to revise the operation schedule lists and discuss when surgery is delayed or changed, and resuscitate patients accordingly. This study will be a baseline information for future research.

Ethical approval and consent to participate

This study was approved by the Institutional Review Board of School of Medicine, College of Health Sciences, Addis Abba University. Permission was also received from medical director of the study hospitals before the commencement of the study.


This work was funded by Addis Ababa University. The sponsor has no role other than funding this research project and enhancing staff research.

Author contribution

All the authors contributed to study conception, design, data collection, performed statistical analysis and interpretation of the result. Mulualem Sitot Fekede and Bereket Alehegn Abebe contributed for writing up and prepared manuscript. All the authors read the manuscript and approved the final submission.

Conflicts of interest disclosure

The authors declare that they have no financial conflict of interest with regard to the content of this report.

Research registration unique identifying number



Mulualem Sitot and Bereket Alehegn

Provenance and peer review

Not commissioned, externally peer-reviewed.


The authors thank the study participants, study hospitals, and data collectors for their assistance and cooperation in the completion of this study.


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Anesthesia; Elective surgery; Preoperative time

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