Laparoscopic Treatment for Appendicitis During Pregnancy: Retrospective Cohort Study
Conditions: Other Specified Complications of Pregnancy
Sponsor: Austral University, Argentina

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STUDY PROTOCOL AND STATISTICAL ANALYSIS PLAN: 
 
LAPAROSCOPIC TREATMENT FOR APPENDICITIS DURING PREGNANCY: RETROSPECTIVE 
COHORT STUDY 
 
Database construction and analysis and study protocol were authorized by the Institutional 
Evaluation Committee under N° B20-010 and P20-070 
 
30/01/2021 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Introduction: 
Acute abdomen in pregnancy (AAP) represents a diagnostic and therapeutic challenge 
due to its multiple obstetric and non-obstetric causes, as well as the anatomical and 
physiological changes that occur during pregnancy, alterations in usual laboratory parameters 
and the reluctance to use diagnostic modalities such as radiography and tomographyi ii.  
Accurate and timely diagnosis and treatment decrease maternal and foetal morbidity 
and mortalityiii. 
Acute appendicitis is the most frequent non-obstetric surgical emergency during 
pregnancy, with an incidence between 0.04% - 0.2%iv v. Although it can occur at any time during 
pregnancy, the incidence is higher in the second trimester. It is the most common cause of non-
obstetric surgical procedures performed during pregnancy, representing 25%vi.  
Other non-obstetric causes of AAP include cholecystitis, ovarian torsion, splenic 
disorders, symptomatic hernias, complications of inflammatory bowel diseases, acute 
pancreatitis, intestinal obstruction, and traumavii. 
In the past, laparoscopy was contraindicated due to the risk of uterine injury with 
surgical instruments, greater technical difficulty due to a reduced working space because of the 
uterus, the concern for foetal acidosis secondary to insufflation with carbon dioxide and the 
decrease in maternal venous return owing to intra-abdominal pressure increase because of 
pneumoperitoneum. Currently, numerous studies have presented laparoscopy as a feasible, 
safe and effective therapeutic option throughout pregnancyviii ix x. 
The benefits of laparoscopy during pregnancy include less uterine manipulation, less 
postoperative ileus, decrease in foetal respiratory depression due to lower narcotic 
requirements for pain management, lower incidence of wound complications and 
thromboembolic events, shorter hospital length-of-stay and a prompt return to normal activityxi 
xii xiii. Nonetheless, complications can occur, and these can affect both the mother and/or the 
foetus.  
 
General Objectives: Describe the results of the laparoscopic treatment of acute appendicitis in 
pregnant women at our institution. 
 
Specific Objectives: 
1- Determine postoperative maternal complications in pregnant women operated on for acute 
appendicitis 
2- Evaluate fetal and perinatological obstetric complications in this group of patients 

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3- Determine if there is a difference between the time from the onset of symptoms to surgical 
resolution and postoperative complications between trimesters of pregnancy. 
4- Determine if there is a difference in the clinical presentation of appendicitis between 
trimesters of pregnancy 
5-Determine if there is a difference in postsurgical morbidity between trimesters of pregnancy 
 
Design: 
Retrospective observational study 
 
Included population 
All pregnant patients with a pre-surgical diagnosis of acute appendicitis operated on at the 
Austral University Hospital between September / 2005 and July / 2020 will be included. 
 
Participants. Inclusion and exclusion criteria 
Database authorized by the Institutional Evaluation Committee under No. B20-010 will be used. 
Included patiets will be those who, prior to their hospitalization, have signed the informed 
consent for hospitalization, in which they give their consent for the use of their health 
information for research purposes. 
 
Inclusion criteria: 
• Age greater than or equal to 18 years 
• Pregnant with a preoperative diagnosis of acute appendicitis. 
 
Exclusion criteria: 
• Patients referred to the Austral Hospital after being operated, to continue the postoperative 
follow-up at our institution. 
• Under 18 years of age. 
 
Data management: 
Data will be obtained from computerized medical records (PECTRA System). Those involved in 
the preparation of the database will access the medical records using a personal, individual, non-

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transferable password, in search only of the information necessary for this study. The lead 
investigator will be able to access with his personal password to audit and control the quality of 
the data load. 
Epidemiological, clinical and laboratory patient data, characteristics of the procedure performed 
and intraoperative findings, postoperative evolution, and maternal-foetal morbidity and 
mortality will be obtained within 30 days of surgery and until the end of pregnancy (described 
in detail in variable description section). The gathered information is part of the usual care and 
surgical practices of the pathology under study. The research protocol will not involve any 
additional procedure on the patients included in it. 
The collected data will be entered into a template made in Excel. Patients will be coded 
according to their clinical history number, and will be anonymized prior to data analysis. 
The data reported will protect the identity of its owner and will be treated with absolute 
confidentiality. 
 
Variables, data source and measurements 
Data will be obtained from the computerized medical records of the PECTRA system. 
The categorical variables will be entered into the Excel template according to a pre-established 
code (see Table below). Continuous variables will be entered with up to 1 decimal place. 
Primary event on which we will analyze the results: surgical morbidity (including intraoperative 
and postoperative complications up to 30 days after surgery). 
 
Variable 
Definition 
Type 
of 
variable 
Data Report 
Age 
Age at the time of surgery 
Continuous 
years 
Gestational Age 
According to the date of the last menstruation 
Continuous 
Days 
Trimester 
<13 weeks: first trimester 
13-26,6 weeks: second trimester 
27 or more weeks: third trimester 
Categorical 
1= first trimester 
2= second trimester 
3= third trimester 
Prior 
abdominal 
surgery 
Abdominal surgery with cavity entry, performed at any 
time prior to the current consultation, whether open or 
laparoscopic. 
Categorical 
0=No 
1=yes 
white 
blood 
cell 
count 
White blood cell count in the laboratory performed on 
admission. 
Continuous 
Cells/mm3 

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Urinary 
sediment 
analysis 
Performing urinary sediment as a complementary study 
at the time of admission. 
Categorical 
0=No 
1=yes 
Murphy Chronology 
Abdominal pain of onset in the epigastrium and 
posterior migration to the right iliac fossa 
Categorical 
0=No 
1=yes 
Rebound 
tenderness 
Presence of pain on abdominal decompression in the 
physical examination performed on admission. 
Categorical 
0=No 
1=yes 
Symptom time 
Time from symptom onset to the start of surgery 
Continuous 
hours 
Abdominal 
Ultrasound 
Carrying out the study as a complementary method of 
diagnosis upon admission 
Categorical 
0=No 
1=yes 
transvaginal 
ultrasound 
Carrying out the study as a complementary method of 
diagnosis upon admission 
Categorical 
0=No 
1=yes 
ASA 
According to the American Society of Anesthesiology 
classification 
Categorical 
1= ASA 1 
2= ASA 2 
3= ASA 3 
4= ASA 4 
Surgery 
Type of surgery carried out  
Categorical 
0= lexploratory laparoscopy 
1= Appendectomy 
2= Colectomy 
Intraoperative 
diagnosis 
Macroscopic characteristics of the appendix evidenced 
during surgical exploration. 
Categorical 
0= Normal 
1= Phlegmonous 
2= Gangrenous 
3= appendicular plastron 
Peritonitis 
Presence of purulent fluid in abdominal cavity 
evidenced during surgical exploration 
Categorical 
0=No 
1=yes 
Conversion 
Modification of the initial laparoscopic approach 
towards the open technique, whatever the incision 
chosen to perform it. 
Categorical 
0=No 
1=Si 
Date of surgery 
Date in which the surgery was performed 
Continuous 
day/month/year 
Surgical time 
Time from initial skin incision to completion of surgery 
and skin closure. 
Continuous 
minutes 
Tocolytics 
Use of tocolytics in the perioperative period 
Categorical 
0=No 
1=yes 
Intraoperative 
complications 
All unexpected intraoperative events, excluding 
conversion to conventional surgery, which were 
analyzed as an independent event. 
Categorical 
0=No 
1=yes 
Uterine injury 
Injury to the gravid uterus, fallopian tubes or ovaries 
during the surgical procedure. 
Categorical 
0=No 
1=yes 
Postoperative 
complications 
Any deviation from the usual postoperative period 
that occurred within 30 days of surgery. 
Categorical 
0=No 
1=yes 
Hospitalization days 
Time elapsed from surgery to hospital discharge. 
Continuous 
Days 
Re-addmission 
Need for re-admission of the patient to the hospital 
for diagnosis or treatment, whatever the cause that 
motivated her re-admission. 
Categorical 
0=No 
1=yes 
Obstetric 
Complication 
Complication arising from the appendectomy to the end 
of the pregnancy, including foetal death and excluding 
preterm delivery. 
Categorical 
0=No 
1=yes 

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Foetal demise 
Including spontaneous or generated abortion or foetal 
death, at any time from hospital admission for surgery 
until the end of the pregnancy. 
Categorical 
0=No 
1=yes 
maternal death 
Patient surgical procedure-related death 
Categorical 
0=No 
1=yes 
Preterm labor 
Delivery or cesarean section before the 37th week of 
pregnancy 
Categorical 
0=No 
1=yes 
Newborn weight 
Newborn weight at delivery or cesarean section 
Categorical 
grams 
Apgar 
At the minute and at 5 minutes 
Categorical 
According to Apgar Scale 
Complete follow-up 
Follow-up from the initial surgery to the end of the 
pregnancy, either by birth (delivery or cesarean section) 
or by fetal or maternal death 
Categorical 
0=No 
1=yes 
 
 
Statistical Analysis plan 
For continuous variables, mean, standard deviation and / or minimum and maximum, or median 
and interquartile interval (IQR) will be used, according to distribution. For categorical variables, 
the number and corresponding percentages will be reported. Continuous parameter 
comparisons will be made using the t-test for independent samples or Wilcoxon-rank test; and 
when there are more than two groups, Anova or Kruskal Wallis will be used. For the comparison 
of categorical variables, the chi-square test or Fisher's exact test will be used, as appropriate. A 
p <0.05 will be considered statistically significant. Likewise, a multivariate analysis will be 
performed for the presence of postoperative complications and obstetric complications. 
The statistical analysis will be performed with STATA version 14.2 (StataCorp 2015. Stata 
Statistical Software: Release 14. College Station, TX: StataCorp LP). 
 
Biases: 
Due to the retrospective nature of the study, we are limited in the information available in the 
medical records. However, we do not believe that the data we wish to obtain is lacking, in 
particular clinical, surgical and complication data, since it is standardized information that is 
always included in the medical record. A complete follow-up of the pregnancy could not be 
fulfilled beyond 30 days after surgery if the patients were cared for outside the HUA, losing 
information on possible obstetric or perinatological complications. We believe that this bias will 
not be of sufficient magnitude to compromise the feasibility of the study. 
 
Sample size: 

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Knowing that we have 63 pregnant women with a pre-surgical diagnosis of acute appendicitis, 
assuming a relationship between surgery within 48 hours of the onset of symptoms and surgery 
after 48 hours of the onset of symptoms of 3: 1, we have an 80% power of find a difference in 
postoperative morbidity between groups of 30% with a type I error of 0.05. 
 
Funding: none 
 
Data Confidentiality and Participant Identity protection: 
Only the doctors involved in this study will have access to the database, and only the doctors 
assigned to load the data will be able to modify it. The lead investigator will also be able to access 
the database to audit the data load. 
Data will be collected in a coded database according to the medical record number. Prior to the 
analysis, data will be anonymized in such a way that the subjects cannot be related to the data. 
The lead investigator may relate the data to the subjects, committing to maintain the highest 
confidentiality and privacy in their handling and not to share them with those who are not 
authorized. 
At the time of publication of the results, the identity of the individuals and the confidentiality of 
their data will be protected, in accordance with the Good Practice Guidelines. 
 
Conflicts of interest: none   
 
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