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Planned interim analysis showed worse outcomes in experimental group
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| Name | Class |
|---|---|
| Medtronic - MITG | INDUSTRY |
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Recent advances in laparoscopic instrumentation have made it possible to perform intra-abdominal operations entirely through a small incision that can be hidden within the umbilicus. The goal is to perform surgery with fewer incisions and no visible scars. Other potential benefits are faster recovery, less pain, and fewer wound complications. The term SILS (Single Incision Laparoscopic Surgery) is being used to describe such techniques, and many have touted SILS as a major breakthrough in minimally-invasive surgery, moving the field closer to surgery that is bloodless, incisionless, and painless. Despite the hype, prospective comparisons of SILS versus conventional laparoscopy are lacking. Results of SILS procedures have generally been limited to case reports and small case series that lack controls. The investigators propose to conduct a prospective, randomized, single-center trial of SILS appendectomy versus conventional laparoscopic appendectomy to treat acute appendicitis. Primary end-points are operative time, complication rate, postoperative pain, recovery time, and long-term cosmetic outcome. The investigators hypothesize SILS appendectomy is equivalent to laparoscopic appendectomy with respect to operative time, complication rate, postoperative pain, and recovery time while providing a better cosmetic outcome.
EXPERIMENTAL DESIGN AND METHODS Patient Enrollment: The study population will consist of patients who come to the emergency room with acute abdominal pain and are found to have acute appendicitis on the basis of clinical evaluation and CT of the abdomen/pelvis. At UCSF, such patients are first evaluated by a small group of general surgeons who provide emergency consultations. Once a decision to operate has been made on clinical grounds, the principal investigator (Dr. Carter) or his delegate will be contacted to approach the patient for enrollment and informed consent.
All patients will receive standard care which consists of preoperative broad-spectrum antibiotics consisting of Zosyn, Ertapenem, or Cipro/Flagyl and intravenous fluids.
Surgeon Enrollment: All surgeons at UCSF who take call in the Emergency Department routinely perform conventional laparoscopic appendectomy for acute appendicitis. Surgeons wishing to participate in the trial will perform 5 proctored SILS appendectomies outside of the trial before enrolling patients. We chose the number 5 because one study showed that SILS operative times (a surrogate for procedural mastery) leveled off by the 5th case for surgeons already proficient in laparoscopy.
Randomization: After enrollment, patients will be assigned to conventional laparoscopic appendectomy versus SILS appendectomy in a 1:1 ratio by a computerized random number generator (http://www.random.org). Even-numbered patients will receive conventional laparoscopic appendectomy, odd-numbered will receive SILS appendectomy.
Conventional laparoscopic appendectomy technique: Patients are placed in the supine position and given a general anesthetic. An orogastric tube is placed. Sequential compression devices are placed on the legs. Unless the patient has just voided, a Foley catheter is placed in the bladder. The left arm is tucked and the abdomen shaved as necessary. The umbilical skin is anesthetized with 5mL of 0.25% marcaine. A 1.5cm vertical or transverse skin incision is made within the umbilical stalk, the fascia is retracted, and a 1.5cm vertical fascial incision made with a scalpel. A 12mm Hasson port is placed through the fascia and the abdomen insufflated to 15mmHg with carbon dioxide gas. Alternatively, a small nick in the fascia can be made, a Veress needle used to achieve pneumoperitoneum, and a 12mm VersSTEP port placed through an introducer sheath. Diagnostic laparoscopy is then performed, with inspection of the stomach, liver, gallbladder, colon, small intestines, and pelvis. If a diagnosis other than acute appendicitis is made (such as pelvic inflammatory disease, sigmoid diverticulitis, cecal diverticulitis, Crohn's disease, perforated duodenal ulcer, etc.), the patient is excluded from the study and treated appropriately. If the appendix looks normal and no other pathology is found in the abdomen, the patient may stay enrolled in the study if the surgeon decides to remove the appendix.
Additional 5mm ports are placed in the left lower quadrant and suprapubic midline after the skin and peritoneum are anesthetized with 0.25% marcaine. A 5mm camera is transferred to the left lower quadrant port site and the appendix is exposed and retracted anteriorly. The mesoappendix may be divided with EndoGIA staplers, Ligasure, cautery and clips, or Harmonic Scalpel. The base of the appendix may be ligated with EndoGIA staplers or Endoloop. The appendix is removed through the umbilical incision after first placing it into an EndoCatch bag. Minimal irrigation is used; perforated cases are treated with suctioning of intra-abdominal pus and postoperative antibiotics. Blood loss is estimated. Umbilical fascia length is measured in millimeters, then closed with 0-Maxon absorbable suture. The umbilical skin is anesthetized with 0.25% marcaine, and all skin edges re-approximated with 4-0 biosyn. Indermil glue is the only dressing.
SILS Appendectomy Technique: Patients are placed in the supine position and given a general anesthetic. An orogastric tube is placed. Sequential compression devices are placed on the legs. Unless the patient has just voided, a Foley catheter is placed in the bladder. The left arm is tucked and the abdomen shaved as necessary. The base of the umbilical stalk is everted by two penetrating towel clamps placed either side of the midline. The skin is anesthetized with 5mL of 0.25% marcaine. A vertical skin incision is made within the umbilical stalk, the fascia is retracted, and a 3 cm vertical fascial incision made with a scalpel. The peritoneum is entered with either a gloved finger, Kelly clamp, or scissors. The incision is retracted anteriorly with an Army/Navy retractor, and the SILSPort inserted into the incision using a shoe-horn maneuver. 5mm trocars are placed in the SILSPort™, and the abdomen insufflated to 15mmHg with carbon dioxide gas, after which the trocars are repositioned into a staggered elevation. Diagnostic laparoscopy is then performed, with inspection of the stomach, liver, gallbladder, colon, small intestines, and pelvis. If a diagnosis other than acute appendicitis is made (such as pelvic inflammatory disease, sigmoid diverticulitis, cecal diverticulitis, Crohn's disease, perforated duodenal ulcer, etc.), the patient is excluded from the study and treated appropriately. If the appendix looks normal and no other pathology is found in the abdomen, the patient may stay enrolled in the study if the surgeon decides to remove the appendix.
The appendix is exposed and retracted anteriorly. The mesoappendix may be divided with EndoGIA staplers, Ligasure, cautery and clips, or Harmonic Scalpel. The base of the appendix may be ligated with EndoGIA staplers or Endoloop. When staplers are used, one of the 5mm trocars is replaced with a 12mm trocar. The appendix is removed through the umbilical incision after first placing it into an EndoCatch bag. Minimal irrigation is used; perforated cases are treated with suctioning of intra-abdominal pus and postoperative antibiotics. Blood loss is estimated. Umbilical fascia length is measured in millimeters, then closed with 0-Maxon absorbable simple interrupted sutures. Skin edges re-approximated with 4-0 biosyn. Indermil glue is the primary dressing.
Postoperative Care: Patients are given a full liquid diet immediately after surgery, and are advanced to an unrestricted diet as soon as the patient feels up to it. Pain is controlled by a hydromorphone PCA (patient-controlled analgesia) pump for at least 12 hours after surgery, after which oral pain medications are prescribed. If the patient is allergic to hydromorphone, morphine may be used. No supplemental pain medications (Motrin, Toradol, etc.) will be used for patients enrolled in the study. No steroids (e.g. Decadron) will be given. Antibiotics for appendicitis are given at the discretion of the attending surgeon. Patients are discharged at the discretion of the attending surgeon, generally when the patient can eat without vomiting, pain is controlled with oral medications, and the systemic inflammatory response to the appendicitis has subsided.
After 2-3 weeks, follow-up occurs in Dr. Carter's clinic. The wounds are assessed for infection, seroma, or hernia. Date of return-to-work and date of last opiate pain medication are recorded. At 6 months, patients return to clinic and complete a survey. The survey includes a Body Image Questionnaire, a Cosmetic Appearance Scale, and a Photo Series Questionnaire, all of which have been validated.8-12 The Body Image Questionnaire measures patients' perception of and satisfaction with their own body and explores attitudes toward their bodily appearance. Five questions are asked, with up to four points assigned per question, totaling 20 possible points. The Cosmetic Appearance Scale assesses the degree of patient satisfaction about the physical appearance of the abdomen (and its scars) using 100-mm visual analogue scale. The patient is asked to make a mark along the horizontal scale that indicates the overall aesthetic appearance of the abdomen as a whole, and incisions separately. Numeric scores are then obtained by measuring the horizontal distance from the low end of the scale to the marking, rounded to the nearest millimeter. Finally, the Photo Series Questionnaire assesses whether knowledge of the cosmetic results of the alternative approach (SILS or conventional laparoscopic) influences the evaluation of the scar. It also measures the strength of the preference. Patients who do not return for follow-up will be mailed a survey and/or called for a telephone interview. Data management and interviews will be managed by a research assistant hired for the study.
Definition of Study Variables and Outcome Measures Patient Characteristics: Age, height, weight, prior operations in the abdomen
Intraoperative Variables:
Postoperative Variables:
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| Label | Type | Description | Intervention Names |
|---|---|---|---|
| SILS appendectomy | Experimental | The study population will consist of patients who come to the emergency room with acute abdominal pain and are found to have acute appendicitis on the basis of clinical evaluation and CT of the abdomen/pelvis. |
|
| Conventional laparoscopic appendectomy | Active Comparator | The study population will consist of patients who come to the emergency room with acute abdominal pain and are found to have acute appendicitis on the basis of clinical evaluation and CT of the abdomen/pelvis. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| SILS appendectomy | Procedure | Use of SILSPort to perform laparoscopic appendectomy |
| |
| Measure | Description | Time Frame |
|---|---|---|
| Pain After Surgery | Mean pain score during 12 hours post-surgery, assessed by the ward nurse as needed, but at least every 4 hours, and documented in the patient's chart. Patients were asked to rate their pain on a scale of 0 to 10, with 10 being the most severe pain imaginable and 0 being no pain at all. | 12 hours post-surgery |
| Measure | Description | Time Frame |
|---|---|---|
| Operative Time | The amount of time to perform the operation from skin-incision to application of the dressing. This time is routinely charted by the circulating nurse in the operating room. | up to 6 hours |
| Procedures Requiring Conversion to Open or Additional Port |
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Inclusion Criteria:
1. Suspected acute appendicitis on clinical and radiographic (CT) grounds
Exclusion Criteria:
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| Name | Affiliation | Role |
|---|---|---|
| Jonathan T. Carter, M.D. | UCSF Department of Surgery | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| UCSF Medical Center | San Francisco | California | 94143 | United States | ||
| University of California, San Francisco |
| PubMed Identifier | Type | Citation | Retractions |
|---|---|---|---|
| 18721008 | Background | Palanivelu C, Rajan PS, Rangarajan M, Parthasarathi R, Senthilnathan P, Praveenraj P. Transumbilical endoscopic appendectomy in humans: on the road to NOTES: a prospective study. J Laparoendosc Adv Surg Tech A. 2008 Aug;18(4):579-82. doi: 10.1089/lap.2007.0174. | |
| Background | Chouillard K FA. Single incision appendectomy for acute appendicitis: a preliminary experience. In: SAGES 2009 Scientific Session, April 22-29, Phoenix, AZ (abstract only); 2009. | ||
| Background | Kravetz AJ ID, Kia MA. Initial experience in single-port laparoscopic appendectomies. SAGES 2009 Scientific Session, April 22-29, Phoenix, AZ (abstract only) | ||
| 19141492 |
| Label | URL |
|---|---|
| Covidien SILSPort website | View source |
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88 patients were assessed for eligibility. 5 patients were excluded because the study surgeon was unavailable to perform the procedure. 6 patients declined to participate.
The study population consisted of all patients from May 2010 to November 2012 who presented to the emergency department and were diagnosed with acute appendicitis on the basis of clinical and radiographic evaluation.
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| ID | Title | Description |
|---|---|---|
| FG000 | SILS Appendectomy | SILS appendectomy: Use of SILS Port to perform laparoscopic appendectomy |
| FG001 | Conventional Laparoscopic Appendectomy | Conventional laparoscopic appendectomy: conventional laparoscopic removal of the appendix |
| Title | Milestones | Reasons Not Completed | |||||
|---|---|---|---|---|---|---|---|
| Short-term Follow-up (Post Operative) |
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| conventional laparoscopic appendectomy |
| Procedure |
conventional laparoscopic removal of the appendix |
|
Patients requiring use of additional incisions and/or trocars, or the need to perform an open procedure. |
| during surgery , up to 6 hours |
| Visceral or Vascular Injury | Number of participants who required intervention (suture or stapled repair, use of hemostatic agents) for injury to the intestines, colon, omentum, vasculature, or pelvic organs during the dissection. | during surgery, up to 6 hours |
| Length of Stay | Number of calendar days the participant was hospitalized. | up to 14 days |
| Wound Infection | Number of participants who required additional antibiotics, prescribed beyond the perioperative antibiotics given for acute appendicitis, for the purpose or treating a wound cellulitis. | 6 months |
| Deep Space Infection | Number of participants who required reoperation, readmission, or percutaneous drainage of a deep (organ space) infection within 6 months of surgery. All intra-abdominal abscesses were classified as deep space infections. | 6 months |
| Wound Seroma | Number of participants who experienced un-inflamed fluid collection under the skin incision > 1cm in diameter identified within 6 months of surgery. | 6 months |
| Time to Return to Work | Number of calendar days between participants' discharge from the hospital and the first day back at work. | 30 days |
| Readmission Within 30 Days. | Number of participants readmitted to the hospital within 30 days of surgery | 30 days |
| Body Image Score at 6 Months | After a minimum of 6 months, a Body-Image Questionnaire was sent to participants. The questionnaire has 5 questions, with answers ranging from 1 (Extremely) to 4 (Not at all); lower scores indicate worse satisfaction with and perception of bodily appearance. Are you less satisfied with our body since the operation? Do you think the operation has damaged your body? Do you feel less attractive as a results of your operation? Do you feel less feminine or masculine as a result of your operation? Is it difficult to look at yourself naked? | 6 months |
| Satisfaction With Physical Appearance of Abdomen and Scars at 6 Months. | The Cosmetic Appearance Scale assessed the degree of satisfaction with the physical appearance of the abdomen (and its scars) using a visual analogue scale. Numeric scores were obtained by measuring the horizontal distance from the low end of the scale to the marking, and then normalized on a scale of 0-20 points. Higher scores indicate a higher degree of satisfaction. Since your operation, how would you describe the overall appearance of your abdomen? (Revolting; Beautiful) Since your operation, how would you describe your incisional scars? (Revolting; Beautiful) How satisfied are you with your incisional scars? (Very unsatisfied; Very satisfied) How much discomfort do your incisional scars cause? (Severe, daily pain; No pain at all) Can you score your own incisional scar? (Worst possible scar; Best possible scar) | 6 months |
| San Francisco |
| California |
| 94143 |
| United States |
| Result |
| Nguyen NT, Reavis KM, Hinojosa MW, Smith BR, Stamos MJ. A single-port technique for laparoscopic extended stapled appendectomy. Surg Innov. 2009 Mar;16(1):78-81. doi: 10.1177/1553350608330528. Epub 2009 Jan 13. |
| Result | Edwards C BA. Single incision laparoscopic appendectomy is safe and results in excellent cosmetic outcomes. SAGES 2009 Scientific Session, April 22-29, Phoenix, AZ (abstract only) 2009. |
| 24684867 | Derived | Carter JT, Kaplan JA, Nguyen JN, Lin MY, Rogers SJ, Harris HW. A prospective, randomized controlled trial of single-incision laparoscopic vs conventional 3-port laparoscopic appendectomy for treatment of acute appendicitis. J Am Coll Surg. 2014 May;218(5):950-9. doi: 10.1016/j.jamcollsurg.2013.12.052. Epub 2014 Feb 19. |
| COMPLETED |
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| NOT COMPLETED |
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| Long-term Follow-up (After 6 Months) |
|
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| ID | Title | Description |
|---|---|---|
| BG000 | SILS Appendectomy | SILS appendectomy: Use of SILS Port to perform laparoscopic appendectomy |
| BG001 | Conventional Laparoscopic Appendectomy | Conventional laparoscopic appendectomy: conventional laparoscopic removal of the appendix |
| BG002 | Total | Total of all reporting groups |
| Units | Counts |
|---|---|
| Participants |
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| Title | Description | Population Description | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Denominator Units Selected | Denominators | Classes | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Age, Continuous | Mean | Standard Deviation | years |
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| Sex: Female, Male | Count of Participants | Participants |
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| Region of Enrollment | Number | participants |
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| Type | Title | Description | Population Description | Reporting Status | Anticipated Posting Date | Parameter Type | Dispersion Type | Unit of Measure | Calculate Percentage | Time Frame | Units Analyzed | Denominator Units Selected | Arm/Group Information | Denominators | Classes | Analyses | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Primary | Pain After Surgery | Mean pain score during 12 hours post-surgery, assessed by the ward nurse as needed, but at least every 4 hours, and documented in the patient's chart. Patients were asked to rate their pain on a scale of 0 to 10, with 10 being the most severe pain imaginable and 0 being no pain at all. | Posted | Mean | Standard Deviation | units on a scale | 12 hours post-surgery |
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| Secondary | Operative Time | The amount of time to perform the operation from skin-incision to application of the dressing. This time is routinely charted by the circulating nurse in the operating room. | Posted | Mean | Standard Deviation | minutes | up to 6 hours |
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| Secondary | Procedures Requiring Conversion to Open or Additional Port | Patients requiring use of additional incisions and/or trocars, or the need to perform an open procedure. | Posted | Number | participants | during surgery , up to 6 hours |
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| Secondary | Visceral or Vascular Injury | Number of participants who required intervention (suture or stapled repair, use of hemostatic agents) for injury to the intestines, colon, omentum, vasculature, or pelvic organs during the dissection. | Posted | Number | participants | during surgery, up to 6 hours |
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| Secondary | Length of Stay | Number of calendar days the participant was hospitalized. | Posted | Mean | Standard Deviation | Days | up to 14 days |
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| Secondary | Wound Infection | Number of participants who required additional antibiotics, prescribed beyond the perioperative antibiotics given for acute appendicitis, for the purpose or treating a wound cellulitis. | Posted | Number | participants | 6 months |
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| Secondary | Deep Space Infection | Number of participants who required reoperation, readmission, or percutaneous drainage of a deep (organ space) infection within 6 months of surgery. All intra-abdominal abscesses were classified as deep space infections. | Posted | Number | participants | 6 months |
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| Secondary | Wound Seroma | Number of participants who experienced un-inflamed fluid collection under the skin incision > 1cm in diameter identified within 6 months of surgery. | Posted | Number | participants | 6 months |
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| Secondary | Time to Return to Work | Number of calendar days between participants' discharge from the hospital and the first day back at work. | Posted | Mean | Standard Deviation | Days | 30 days |
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| Secondary | Readmission Within 30 Days. | Number of participants readmitted to the hospital within 30 days of surgery | Posted | Number | participants | 30 days |
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| Secondary | Body Image Score at 6 Months | After a minimum of 6 months, a Body-Image Questionnaire was sent to participants. The questionnaire has 5 questions, with answers ranging from 1 (Extremely) to 4 (Not at all); lower scores indicate worse satisfaction with and perception of bodily appearance. Are you less satisfied with our body since the operation? Do you think the operation has damaged your body? Do you feel less attractive as a results of your operation? Do you feel less feminine or masculine as a result of your operation? Is it difficult to look at yourself naked? | 67 of 75 patients completed and returned follow-up surveys | Posted | Mean | Standard Deviation | units on a scale | 6 months |
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| Secondary | Satisfaction With Physical Appearance of Abdomen and Scars at 6 Months. | The Cosmetic Appearance Scale assessed the degree of satisfaction with the physical appearance of the abdomen (and its scars) using a visual analogue scale. Numeric scores were obtained by measuring the horizontal distance from the low end of the scale to the marking, and then normalized on a scale of 0-20 points. Higher scores indicate a higher degree of satisfaction. Since your operation, how would you describe the overall appearance of your abdomen? (Revolting; Beautiful) Since your operation, how would you describe your incisional scars? (Revolting; Beautiful) How satisfied are you with your incisional scars? (Very unsatisfied; Very satisfied) How much discomfort do your incisional scars cause? (Severe, daily pain; No pain at all) Can you score your own incisional scar? (Worst possible scar; Best possible scar) | Participants who returned surveys for long-term follow-up | Posted | Mean | Standard Deviation | units on a scale | 6 months |
|
6 months
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| ID | Title | Description | Deaths (Affected) | Deaths (At Risk) | Serious Events (Affected) | Serious Events (At Risk) | Other Events (Affected) | Other Events (At Risk) |
|---|---|---|---|---|---|---|---|---|
| EG000 | SILS Appendectomy | SILS appendectomy: Use of SILS Port to perform laparoscopic appendectomy | 0 | 37 | 5 | 37 | ||
| EG001 | Conventional Laparoscopic Appendectomy | Conventional laparoscopic appendectomy: conventional laparoscopic removal of the appendix | 0 | 38 | 4 | 38 |
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| Term | Organ System | Source Vocabulary | Assessment Type | Notes | Statistical Information |
|---|---|---|---|---|---|
| Deep space infection | Infections and infestations | Systematic Assessment | Reoperation, readmission, or percutaneous drainage of a deep (organ space) infection within 6 months of surgery |
| |
| Wound seroma | Skin and subcutaneous tissue disorders | Systematic Assessment | Un-inflamed fluid collection under the skin incision, >1cm in diameter, identified within 6 months of surgery |
| |
| Postoperative bleeding | Injury, poisoning and procedural complications |
| |||
| Urinary retention | Renal and urinary disorders |
| |||
| Prolonged postoperative ileus | Gastrointestinal disorders |
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| Title | Organization | Phone | Extension | |
|---|---|---|---|---|
| Jonathan T. Carter, MD, FACS | University of California, San Francisco | 415-476-0974 | jonathan.carter@ucsfmedctr.org |
| ID | Term |
|---|---|
| D001064 | Appendicitis |
| ID | Term |
|---|---|
| D059413 | Intraabdominal Infections |
| D007239 | Infections |
| D005759 | Gastroenteritis |
| D005767 | Gastrointestinal Diseases |
| D004066 | Digestive System Diseases |
| D002429 | Cecal Diseases |
| D007410 | Intestinal Diseases |
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