Resuming Bariatric Surgery Procedures During COVID-19 Pandemic: Early Surgical Outcomes at a Tertiary Referral Center in the Middle East

Abstract

Background:

In response to the COVID-19 pandemic, elective surgical procedures have been delayed. Even with the implementation of surgical societies' recommendations, patient safety remains a concern. This study evaluates the postoperative outcomes in patients undergoing bariatric surgery after reopening (RO) elective surgery during the COVID-19 pandemic.

Methods:

All patients who underwent bariatric surgery from September 2015 to July 2020 were included. Patients were divided into two cohorts: the pre-COVID-19 (PC) cohort and the RO cohort. Propensity score weighting was used to evaluate postoperative outcomes.

Results:

Our study included 1076 patients, 1015 patients were in the PC and 61 patients in the RO. Sixty-four percent were female with a mean age of 37 years and median body mass index of 41 kg/m². There were no statistically significant differences in 30 days perioperative outcomes, including emergency department visits 24.8% PC versus 19.7% RO (p = 0.492), readmission 4.2% PC versus 8.2% RO (p = 0.361), reoperation 2.6% PC versus 0% RO (p = 0.996), and major complications 4.0% PC versus 4.9% RO (p = 0.812). No patients in the RO contracted COVID-19.

Conclusions:

With the appropriate policies and precautionary measures, there appear to be no differences in the 30-day postoperative outcomes before and during the COVID-19 pandemic.

Introduction

Since the first case was identified in Wuhan City, China, in December 2019, the novel coronavirus (COVID-19) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has >117.5 million cases as of March 8, 2021.^1,2 There have been 2,606,881 mortalities worldwide.³ As a consequence, the implementation of multiple new guidelines was aimed to protect the patients and health care providers' safety from the disease. This has directly impacted surgeons' daily practices and led to unprecedented demands on health care resources globally.^4–7

One major recommendation from various surgical societies is to postpone or to cancel elective surgeries during the early stages of the pandemic.¹ This was a necessary decision, as the spread of the disease had resulted in resource shortages ranging from health care providers to equipment. In addition, these precautions were aimed to protect patients from hospital viral transmission and associated postoperative complications. The full impact of these delays is unknown. However, a total of 28,404,603 surgeries were estimated to be canceled or postponed during the 12-week peak of the COVID-19 pandemic, with 2,367,050 operations being canceled every week.¹

Early studies have shown an increase in postoperative morbidity and mortality in patients who underwent surgery during the incubation period of COVID-19,^8–10 with some studies reporting mortality rates as high as 27.5% in patients who underwent elective surgery with an unknown COVID-19 status and developed COVID-19 postoperatively.¹⁰ Patients who contracted COVID-19 preoperatively were exposed to a higher rate of intensive care unit (ICU) admission in the COVID-19 cohort of 36.1% versus 16.4%.¹¹ In particular, patients who have obesity are at a higher risk for severe COVID-19-related ICU admissions, intubation, and death.^12,13 Therefore, the contraction of COVID-19 in a bariatric surgical population is an important consideration. Recently, many countries around the world have reopened elective programs and resumed elective bariatric surgeries to mitigate the large backlog of patients. Nonetheless, patient safety remains a concern. There has been a joint effort between surgical societies and governmental authorities to overcome the safety aspect of reopening (RO) operations. Data reported in this field are limited and the demand to restart elective procedures is increasing rapidly.

The purpose of this study aims to evaluate postoperative outcomes in patients undergoing bariatric surgeries after RO elective surgeries during the first COVID-19 peak compared with a historical cohort.

Materials and Methods

Study design and ethical considerations

This retrospective study was conducted at a single academic medical institution located in the United Arab Emirates (UAE). All patients who underwent primary and revisional bariatric surgery between September 2015 and July 2020 were reviewed. Data were collected from a prospectively maintained registry and a retrospective analysis was performed. This study has been approved by our Institutional Review Board.

Cohort groups

The pre-COVID (PC) cohort included patients who underwent surgery from September 15, 2015 to March 11, 2020. The RO cohort included a series of patients who tested negative for COVID-19 and underwent surgery from June 1, 2020 to July 31, 2020, which represented the first peak phase in the UAE. As per World Health Organization's (WHO) declaration of a global pandemic, our institution began to cancel all elective procedures as of March 11, 2020. After obtaining an institutional approval, our department of surgery was approved to resume elective procedures as of June 1, 2020.

At the time of restarting bariatric surgeries, the UAE had just reached its peak number of daily cases, of 635 and a total of 35,192 cases related to COVID-19.¹⁴ At that time UAE had strict measures to reduce COVID-19 transmission rates, including prohibiting overcrowding in public places and large gatherings, mandatory temperature checks at all public places, social distancing, and mask wearing. Fines ranging from 1000 dirhams (DHS) (272 USD) to 50,000 DHS (13,612 USD) have been set for failure to comply with the country's COVID-19 safety regulations. In our institution, it was required for all patients to undergo COVID-19 polymerase chain reaction (PCR) swab 48 h preoperatively. The hospital restricted family visitations by; limiting to only two family members at a time and reduced visitation hours. All visitors entering the hospital as well as caregivers are required to wear masks at all times. Following the UAE governmental policies, our institution was selected to be a COVID-19-free facility; therefore, all COVID-19 patients were then transferred to designated COVID-19 facilities.

Patient selection

The RO of the bariatric surgery program was selective at the discretion of the surgeon. Patient selection emphasized on those who would benefit the most from their symptomatic complications and have a higher degree of comorbid disease. This was initially selected by the surgeon and then reviewed at our multidisciplinary team meeting, to minimize risk to the patients and medical staff. Patients were prioritized based on the following criteria: asymptomatic patients (i.e., no flu-like symptoms, fever, and shortness of breath), no previous COVID-19 infection, age <60 years, body mass index (BMI) ≤50 kg/m², and controlled comorbidities (i.e., diabetes, hypertension, and cardiac diseases) that might worsen the health burden of the patients.

Baseline and surgical outcomes

Patient demographics, including age, gender, BMI, and comorbidities, were collected. Operation details such as the type of bariatric surgery were reviewed. Perioperative outcomes, including length of stay, ICU admissions, emergency department (ED) visits, readmissions, reoperation, complications, and mortality within 30 days, were also analyzed. For the PC cohort, pre- and postoperative COVID-19 PCR testing results and the development of any related symptoms were included.

Statistical analysis

Baseline descriptive statistics for each group (PC and RO patients) were calculated for demographic and clinical variables. Continuous variables were presented as means with standard deviations (SDs), or medians with interquartile ranges (IQRs). Categorical data were presented as frequencies and percentages.

Inferential analyses comparing groups on endpoint variables were also performed: group differences and associated p-values comparing PC and RO patients were calculated using independent samples t-tests when examining continuous variables, and logistic regression when examining dichotomous variables. To account for possible confounding when making these group comparisons, a propensity score weighting strategy was utilized. In this study, all baseline demographics and baseline clinical variables were used to estimate the propensity score through a main-effects logistic regression.

Weights designed to statistically align the PC patient group with the RO group (in terms of variables used to estimate the propensity score) were then calculated from the propensity score using the treatment effect on the treated weighting strategy described by Hirano and Imbens.¹⁵ Adjusted group comparisons were calculated by incorporating these weights through weight least square estimation. Unadjusted group differences and propensity weight adjusted group differences are provided in the same tables to illustrate the effects weighting on these inferential group comparisons. In all instances, the criterion for determining statistical significance was set to a two-tailed alpha of 0.05. Statistical analyses were performed using R version 3.5.1.

Results

Our study included 1076 patients, 64% were female with a mean age of 37 years and median BMI of 41 kg/m². Eight hundred four (74.7%) cases were primary and 272 (25.3%) cases were revisions. One thousand fifteen patients were in the PC cohort and 61 patients in the RO cohort. Average age was 37 ± 11.3 years in the PC cohort and 35 ± 10.5 years in the RO cohort (p = 0.158). The average BMI was 42 ± 8.2 and 42 ± 7.2, respectively. There were 64% females in the PC group and 68% females in the RO group (p = 0.587). Median American Society of Anesthesiologist (ASA) scores were the same at three (IQR 2, for both groups). All 61 patients from the RO cohort were tested for COVID-19 at least 2 days before their operation date following our institutional guidelines, with 90% (n = 55) being tested at our hospital. All patients were tested negative preoperatively (Table 1).

Table 1.

Baseline Characteristics

N = 1076
Variables	PC (n = 1015)	RO (unweighted) (n = 61)	p
Age (average ± SD; years) [range, years]	37 ± 11.3 [16–71]	35 ± 10.5 [19–61]	0.178
Male	368 (36.2%)	20 (32.8%)	0.5823
Female	647 (63.7%)	41 (67.2%)	0.5823
BMI (average ± SD)	42 ± 8.2	42 ± 7.2	1
ASA (median: IQR)	3 (2)	3 (2)	1
Comorbidities
T2DM	242 (23.8%)	9 (14.8%)	0.1031
COPD	10 (1.0%)	0 (0%)	0.4354
DVT/PE	16 (1.6%)	1 (1.6%)	0.9681
OSA	251 (24.7%)	15 (24.6%)	0.98404
GERD	358 (35.3%)	31 (50.8%)	0.01428
CAD	32 (3.2%)	1 (1.6%)	0.50286
HTN	282 (27.8%)	12 (19.7%)	0.16758
HLD	374 (36.8%)	9 (14.8%)	0.00046
CKD	33 (3.3%)	2 (3.3%)	0.99202
ESRD	5 (0.5%)	0 (0%)	0.58232
Type of bariatric surgery
Primary	760 (74.9%)	44 (72.1%)	0.63122
Revision	255 (25.1%)	17 (27.9%)	0.63122

ASA, American Society of Anesthesiologists; BMI, body mass index; CAD, coronary artery disease; CKD, chronic kidney disease; COPD, chronic obstructive pulmonary disease; DVT/PE, deep venous thrombosis/pulmonary embolism; ESRD, end-stage renal disease; GERD, gastroesophageal reflux disease; HLD, hyperlipidemia; HTN, hypertension; IQR, interquartile range; OSA, obstructive sleep apnea; PC, pre-COVID; RO, reopening; SD, standard deviation; T2DM, type 2 diabetes mellitus.

Of all patients in the PC group, 74.9% of patients underwent primary bariatric surgery (Roux-en-Y gastric bypass or sleeve gastrectomy) and 25.1% underwent revisions. In the RO cohort, 72.1% of patients underwent primary bariatric surgery and 27.9% underwent revisions. Both groups were then matched using a propensity score weighting scheme on the bases on a list of confounding variables (Table 2).

Table 2.

Confounding Variables by Group by Propensity Score Weighting Scheme

N = 1076
		Unweighted/unmatched		Weighted/matched
	RO (n = 61)	PC (n = 1015)	p	PC (n = 61)	p
Age	35.39	37.49	0.158	35.27	0.845
Gender (male)	32%	36%	0.587	33%	0.986
Smoker	18%	14%	0.411	17%	0.920
ASA Class 1	3%	3%	0.760	3%	0.961
ASA Class 2	31%	37%	0.366	31%	0.988
ASA Class 3	66%	60%	0.403	66%	0.997
ASA Class 4	0%	0%	0.995	0%	1.000
SG	48%	44%	0.549	48%	0.982
RYGB	25%	32%	0.244	24%	0.984
SG to RYGB	15%	16%	0.847	15%	0.970
MGB to RYGB	0%	2%	0.986	0%	1.000
RYGB to distalization	5%	1%	0.042	5%	0.974
Other	8%	5%	0.273	8%	0.973
Laparoscopic	90%	96%	0.040	90%	0.975
Open	0%	0%	0.995	0%	1.000
Robotic	10%	4%	0.031	10%	0.975

MGB, mini gastric bypass; RYGB, Roux-en-Y gastric bypass; SG, sleeve gastrectomy.

There were no statistically significant differences in the intraoperative complication rate, including blood loss >100 mL: 0.3% PC weighted versus 0% RO (p = 0.999) and intraoperative complications: 0.4% PC weighted versus 0% RO (p = 0.998). There is statistically significant differences in procedure duration (minutes) when comparing RO group with PC weighted: 137 min PC weighted versus 145 min RO (p = 0.019) indicating a difference of 8 min (Table 3).

Table 3.

Comparison of Intraoperative Outcomes

N = 1076
		Unweighted/unmatched		Weighted/matched
	RO (n = 61)	PC (n = 1015)	p	PC (n = 61)	p
Blood loss >100 mL	0%	0.39%	0.995	0.27%	0.999
Intraop complication	0%	0.80%	0.991	0.40%	0.998
Proc. duration (minutes)	145.05	141.995	0.712	136.62	0.019

There were no statistically significant differences in perioperative minor complications within 30 days: 5.4% PC weighted versus 4.9% RO (p = 0.895) and major complications within 30 days visits: 4.0% PC weighted versus 4.9% RO (p = 0.812). Only 3.3% (2 patients) in the RO cohort developed endoluminal gastrointestinal bleeding requiring intervention, compared with 2.4% (24 patients) in the PC weighted (p = 0.763). With 1.6% of RO cohort requiring postoperative transfusion compared with PC weighted (p = 0.541) (Table 4).

Table 4.

Comparison of Perioperative 30-Day Complication

N = 1076
		Unweighted/unmatched		Weighted/matched
	RO (n = 61)	PC (n = 1015)	p	PC (n = 61)	p
Early minor complications	4.90%	5.30%	0.883	5.44%	0.895
Nausea and vomiting	3.20%	2.90%	0.872	2.98%	0.924
Trocar/surgical site infection	0%	1.26%	0.991	0.99%	0.998
Pneumonia	0%	0.19%	0.995	0.07%	0.999
UTI	3.27%	0.68%	0.049	0.99%	0.407
Dumping syndrome	0%	0%	0.995	0.90%	0.998
Early major complications (<30 days)	4.92%	4.87%	0.986	4.03%	0.812
VTE	0%	0%	0.995	0.28%	0.999
Anastomotic leakage	0%	1.46%	0.991	11.70%	0.998
GI bleeding	3.28%	2.82%	0.836	2.37%	0.763
Postoperative transfusion	1.63%	0.68%	0.410	0.44%	0.541
SBO	0%	0%	0.995	0.30%	0.999
Bowel perforation	0%	0%	0.995	0%	1.000
Surgical site infection	0%	0%	0.995	0.09%	0.999
MI	0%	0%	1.000	0%	1.000
Respiratory failure	0%	0%	0.995	0.20%	0.999
Sepsis	0%	0.58%	0.992	0.41%	0.998
Cerebrovascular accident	0%	0.19%	0.995	0.11%	0.999
Endoscopy needed within 30 days	3.28%	2.24%	0.601	2.00%	0.663
Placement of percutaneous drain	0%	0.88%	0.991	0.56%	0.998

GI, gastrointestinal; MI, myocardial infarction; SBO, small bowel obstruction; UTI, urinary tract infection; VTE, venous thromboembolism;.

There were no statistically significant differences in perioperative outcomes (Table 5), including ED visits in 30 days: 24.8% PC weighted versus 19.7% RO (p = 0.492). Reasons for ED presentation in RO cohort included allergic reaction and rash, noncardiac chest pain, and nonsurgical abdominal pain. Out of the 12 patients, 1 patient developed upper respiratory-like symptoms; however, COVID-19 was ruled out with two consecutively negative PCR swabs. Readmission rates in 30 days were 4.2% PC weighted versus 8.2% RO (p = 0.361), reoperations were 2.6% PC weighted versus 0% RO (p = 0.996), and length of stay were 2.8 days PC weighted versus 2.9 days RO (p = 0.381). There were no anastomotic leaks or deaths in either groups during the study period.

Table 5.

Comparison of Perioperative 30-Day Outcomes

N = 1076
		Unweighted/unmatched		Weighted/matched
	RO (n = 61)	PC (n = 1015)	p	PC (n = 61)	p
Length of stay (days)	2.96	3.12	0.810	2.80	0.381
ED visits (within 30 days)	19.67%	24.15%	0.427	24.84%	0.492
Death	0%	0%	1.000	0%	1.000
Readmissions (within 30 days)	8.19%	4.67%	0.221	4.16%	0.361
Reoperations number within 30 days	0%	3.02%	0.986	2.55%	0.996
Therapeutic endoscopy	4.92%	5.55%	0.834	5.38%	0.909
Stent	0%	1.16%	0.991	1.12%	0.998
Dilation	3.27%	4.09%	0.755	42.11%	0.786
GGF closure	0%	0%	1.000	0%	1.000
Stoma resizing	0%	0%	1.000	0%	1.000
PEG placement	0%	0.10%	0.997	0.11%	0.999
ERCP	0%	0%	1.000	0%	1.000
Other endoscopes	1.63%	0.88%	0.551	0.85%	0.701

ED, emergency department; ERCP, endoscopic retrograde cholangiopancreatography; GGF, gastrogastric fistula; PEG, percutaneous endoscopic gastrostomy.

No patients contracted COVID-19 postoperatively. Seventeen percent (n = 10) required a repeat COVID-19 test during the postoperative period, due to range of causes such as developing upper respiratory symptoms or screening for a nonbariatric-related procedure. All repeated tests were negative.

Discussion

The RO of elective surgeries during the COVID-19 pandemic has been a matter of debate, due to the limited data available regarding the safety of restarting elective cases. To our knowledge, no previous studies have reported postoperative outcomes in patients undergoing bariatric surgeries during the initial peak of the COVID-19 pandemic. This study demonstrates that there is no difference in the 30-day postoperative outcomes among patients who underwent bariatric surgery during the COVID-19 initial peak when compared with a historical cohort. Our results suggest that there are no increased risks associated with performing bariatric surgery, given the patients were COVID-19 negative preoperatively and appropriate precautions consistent with current recommended best practices are implemented.^7,16 The only statistically significant change is prolonged procedure duration of 8 min between the PC cohort and RO cohort. This could be due to strict operating room precautions including personnel in the procedure area. At the time of restarting bariatric surgeries as of June 1, 2020, the UAE had just reached its peak number of daily cases, of 635 and a total of 35,192 cases related to COVID-19.¹⁴ At that time, UAE had strict measures to reduce COVID-19 transmission rate with prohibiting overcrowding in public places and large gatherings, mandatory temperature checks at all public places, social distancing, and mask wearing.

Emerging data can be used as a guide to determine postoperative risks and the role of screening as an essential strategy to help control the morbidity and mortality associated with surgery in the postpeak COVID-19 era. Early studies have shown that COVID-19 poses a substantial risk for patients undergoing surgical procedures with higher mortality due to severe pulmonary complications. A case series described patients who underwent elective surgery with unknown COVID-19 status reported a 78% diagnosis rate with COVID-19 in the postoperative period, and the mortality rate was 27.5%.¹⁰ Another study comparing COVID-19 positive patients with COVID-19 negative controls found a perioperative mortality rate of 16.7% compared with 1.4% in the control.¹¹ Higher rates of ICU admissions were seen in the COVID-19 positive cohort.

Reports from the COVIDsurg collaborative evaluating surgical patients operated between January and March 2020 with positive COVID-19 during the perioperative period estimated a 30-day mortality rate of 18.9% in patients who underwent elective surgery.¹⁷ Mortality rate increased to 22.3% in patients who underwent emergency surgery.¹⁷ The COVIDsurg collaborative also associated high mortality from COVID-19 with advanced age and male gender. The latest report by Lei et al., suggested that there is a 20% postoperative mortality rate among asymptomatic COVID-19 patients who underwent elective surgery.⁸ In these studies, the patients were not screened for COVID-19 preoperatively. These rates have been accumulated from a study early on in the pandemic when testing capabilities were limited and patients did not get preoperative COVID testing. Therefore, the potential preoperative screening can be used as an essential tool to significantly decrease morbidity and mortality associated with surgery during COVID-19 when restarting elective services. A recently published study evaluating the safety of restarting elective traumatic upper limb day-case surgery reported zero mortality when precautions such as preoperative screening were implemented before procedures.¹⁸

Multiple guidelines have been published earlier in the pandemic recommending to postpone all elective cases.^7,16,19,20 More recently, scientific articles and guidelines aiming to support the recommencement of elective surgeries safely have started to emerge and included a comprehensive list of considerations before restarting elective services.

The International Federation for the Surgery of Obesity (IFSO) recommendation, as of March 2020, is to postpone all elective bariatric surgeries.²¹ If surgery is to be considered, strict measures should be followed. Recently published protocol regarding recommencement of bariatric surgery based on experts' opinions and small series, offered recommendations on patient eligibility and preoperative as well as postoperative recommendations.²⁰ Surgery should be gradually restarted and patients should be chosen based on a set of eligible criteria. Even patients aged between 20 and 30 years and nonsmokers with no pulmonary disease should be screened for COVID-19 before surgery. All patients must be treated as if they are suspected to be COVID-19 positive and should be treated with proper personal protective equipment. Postoperative follow-up consultations should be through telemedicine to minimize patient's risk.

The American College of Surgeons (ACS) as of April 2020 have provided a set of principles to help with restarting elective surgeries.⁷ The 10 distinct principles cover concepts regarding community's COVID-19 prevalence, the facility preparedness with testing capability, personal protective equipment, facility and health care worker availability, will have to be addressed before elective surgery can be safely reinstituted. The need for continuous monitoring of the changing situation is needed with a real-time governing body to make decisions. Recommendations for testing of patients preoperatively should be available at any institute as well.

This study has limitations that are to be expected in retrospective studies. The accuracy and availability of medical records and information might be affected due to the nature of the data collection. In addition, the sample size of our study is small, there are only 61 patients during the RO period with a short follow-up period. This limits our ability to fully understand the long-term complications of operating during the COVID-19 era. However, the strength of this study remains to be one of the earliest to discuss the safety of restarting elective bariatric surgery during the COVID-19 era. Data from this study can be used in future viral epidemic outbreaks.

Conclusions

In summary, this retrospective cohort study showed no difference in the 30-day postoperative outcomes among patients who underwent bariatric surgery before and during the COVID-19 initial peak when strict policies and precautionary measures were followed. However, the findings in this article suggest that elective surgery may be carried out with acceptable risks in selected groups of COVID-19 negative patients with strict perioperative care and country regulations. The ability to replicate similar outcomes in other countries will depend on local prevalence rate, available vital hospital resources, and strict measures.

Footnotes

Author Disclosure Statement

No competing financial interests exist.

Funding Information

No funding was received.

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