Reversal of Hartmann's procedure– why is it delayed?

Örebro University

School of Medical Sciences Degree project, 15 ECTS January 2021

Reversal of Hartmann's procedure

– why is it delayed?

Version 2

Author: Josefine Larsson Supervisor: Peter Matthiessen, MD, PhD, Adjunct Professor Örebro, Sweden

Abstract

Background: Reversal of Hartmann’s procedure with restoration of intestinal continuity increase

patients’ quality of life but entails considerable risks of postoperative morbidity.

Aim: Our aim was to investigate the timing of Hartmann’s reversal and factors delaying stoma

closure. Secondarily, postoperative complications in relation to reversal surgery were reviewed.

Methods: This retrospective record review evaluated all patients undergoing reversal of Hart­

mann’s procedure during a 9­year period. Reversal beyond 6 months was deemed delayed.

Results: A total of 42 patients were included in the study. Common surgical indications were

malignancy (n=14) and diverticular disease (n=12). Median time to reversal was 12 months. Only 12% of stomas were reversed within 6 months, with no significant difference between the malig­ nant and non­malignant groups. The remaining 88% were considered delayed reversals. Adjuvant chemotherapy caused a delay in 64% of patients with a malignant surgery indication. In the non­ malignant group, low priority within the healthcare system caused 57% of delays, while 17% were due to the patient’s choice. Postoperative morbidity affected 64% (n=27) of patients. Wound infec­ tion (n=8), abscess formation (n=6), ileus (n=7) and incisional hernia (n=8) were the most frequent complications. No deaths occurred postoperatively.

Conclusion: Almost 9 in 10 patients had a delayed stoma reversal, beyond 6 months. The main

Contents

Abbreviations . . . 4

Introduction . . . . 4

Aim . . . . 5

Material and methods . . . . 6

Study design . . . 6 Definitions . . . 6 Delay . . . 6 Smoking . . . 6 ASA classification . . . 6 Analyzed variables . . . 7 Statistical analysis . . . 7 Ethics . . . 7 Results . . . . 8 Study population . . . 8

Pre­ and perioperative details . . . 10

Postoperative course . . . 14

Discussion . . . 16

Strengths and limitations . . . 18

Conclusion . . . . 18

Acknowledgement . . . . 19

Abbreviations

• HA: Hartmann’s procedure

• ASA: American Society of Anesthesiologists

• BMI: Body mass index

• Hb: Hemoglobin

• CRC: Colorectal cancer

Introduction

In 1921 the French surgeon Henri Albert Hartmann introduced a surgical treatment for obstructive rectosigmoid cancer, with postoperative outcomes superior to other techniques at the time [1]. Since then, the operation has been known as Hartmann’s procedure and includes resection of the sigmoid colon, or the sigmoid colon and part of the rectum, construction of an end colostomy and closure at the rectal stump. Indications for Hartmann’s procedure have broadened beyond malignancy to encompass other diseases of the left colon, primarily complicated diverticulitis with perforation and purulent or fecal peritonitis [2]. Hartmann’s procedure is currently the treatment of choice for this condition [3] as it eliminates the risk of anastomotic leakage associated with primary anastomosis [4], however, leakage at the rectal suture line is still a possibility.

Hartmann’s procedure is used to resolve acute clinical situations, where other surgical approaches are deemed less safe [5, 6], but its use in elective contexts is limited.

Performing Hartmann’s procedure retains the opportunity to restore intestinal continuity and op­ timal digestive functionality at a later stage. This can be done once the acute clinical situation is resolved, and the patient has healed from previous surgery. To reverse Hartmann’s procedure, the colostomy site is closed, whereupon an anastomosis is constructed between the descending colon and the distal sigmoid colon or the rectal stump.

Stoma reversal is usually the end objective when performing Hartmann’s procedure, but every other patient is left with permanent colostomy [3, 5, 7]. Reversal surgery impose considerable risks of

postoperative morbidity and even mortality [3, 5, 7], possibly explaining the relatively low reversal rate. Well documented complications include anastomotic leakage, wound infection, intraabdomi­ nal abscess formation, ileus and incisional hernia, among others [8, 7, 3, 9]. Nevertheless, patients living with a colostomy following Hartmann’s procedure can be affected by stoma related compli­ cations and experience a reduced quality of life, compared to patients who have undergone reversal [10]. The reality that many patients are left with stomas for an extended period of time or even per­ manently is therefore problematic.

Efforts have been made to identify the ideal timing of stoma reversal, but a consensus has not been reached. Some authors suggest delaying reversal by 15 weeks to reduce postoperative complica­ tions [11], while others recommend reversal after 6 months, enabling adhesions to soften, reducing operative difficulty [12]. Fleming et al found reversal within 9 months beneficial, while increased time to reversal correlated with inferior outcomes [13], potentially explained by shrinkage of the rectal stump, as suggested by Roe et al [14]. In reality, median time to reversal display a large variability in preceding literature, ranging from 3­11 months [15, 16, 14, 17, 9, 18, 8, 2]. Despite this, earlier research has failed to report reasons for delayed reversal, in cases of prolonged reversal times.

Aim

The primary objective of this study was to determine time to stoma reversal after Hartmann’s pro­ cedure and factors contributing to delayed stoma closures. A secondary objective was to review postoperative complications following stoma reversal.

Material and methods

Study design

This retrospective record review evaluated all patients undergoing Hartmann’s procedure or comparable surgeries, with subsequent colostomy reversal between February 2010 and August 2019 at the Department of Surgery, Örebro University Hospital. Patients were identified by search of the following surgical procedure codes in a pre­existing database:

• JFG36 colostomy closure with rectal anastomosis.

• JFG33 colostomy closure with colonic anastomosis.

• JFG30 colostomy closure with bowel resection.

The procedure codes identified a broader study population than intended. Appropriate pa­ tients were therefore selected based on type of index operation.

Definitions

Based on the review of existing literature, stoma reversal within 6 months following Hart­ mann’s procedure was concluded to be a reasonable ambition. Accordingly, stoma reversal beyond 6 months (183 days) was defined as delayed, however, this definition remains ar­ bitrary.

Smoking

Data regarding smoking was collected from preoperative anesthesia assessments. Only patients registered as current smokers at the time of reversal surgery were labeled smokers. Former smokers were categorized as non­smokers.

ASA classification

American Society of Anesthesiologists (ASA) physical status classification system is used to assess patient health preoperatively. Patients are divided into six categories based on the following definition:

”ASA­Physical Status Class . . . I: A normal healthy patient . . .

II: A patient with mild systemic disease . . . III: A patient with severe systemic disease . . .

IV: A patient with severe systemic disease that is a constant threat to life . . . V: A moribund patient who is not expected to survive without the operation . . .

VI: A declared brain­dead patient whose organs are being removed for donor purposes” [19]. Reversal of Hartmann’s procedure is an elective operation, because of this, patients classified as ASA 5 or 6 are not eligible candidates for this procedure.

Analyzed variables

Data collection was centered around variables describing patient demographics, intraoper­ ative data and postoperative outcome. Demographic details gathered were age, sex, body mass index (BMI), ASA grading, cancer stage, smoking, laboratory results (hemoglobin and creatinine), surgical indication, emergency management or not, time interval between Hartmann’s procedure and stoma reversal and whether the reversal surgery was conducted in a laparoscopic or open manner. Intraoperative variables were operation time and bleed­ ing. Measures of postoperative outcome were duration of hospital stay, treatment with antibiotics beyond prophylaxis, frequency and reasons for unplanned readmission and re­ operation within 90 days, postoperative complications and mortality.

Statistical analysis

Relevant patient data was compiled in Microsoft Excel 2011 and processed in the data analysis­ and manipulation tool Pandas to generate descriptive statistics, tables and fig­ ures. Median was used as a measure of central tendency, and range to describe statistical dispersion. Shares are stated as percentages. In the primary analysis, time interval between Hartmann’s procedure and stoma reversal, reasons for delayed reversal and postoperative complications were assessed.

Ethics

This retrospective record review aimed to acquire information about a course of medical care. Approval was obtained from the operations manager at the Department of Surgery,

Örebro University Hospital. To avoid bias, patients were not asked for consent. Patient data is stored on a USB­drive and encrypted with AES­256 to mitigate the risk of unwar­ ranted exposure of sensitive patient details in the event that the drive is lost. The data will be anonymized when the report has been approved. Results are presented on a group level to avoid the risk of individuals being identified.

Results

Study population

A total of 59 patient charts were included in the primary review, of which three were dupli­ cates, another 14 patients did not fit the inclusion criteria and were excluded from further analysis. Lastly 42 patients who underwent Hartmann’s procedure (n=33) or compara­ ble surgeries (n=9) with subsequent end colostomy reversal remained. Data was collected from these patients. Selection of comparable surgeries was made in consultation with a colorectal surgeon and the decision to include these patients was undertaken to increase the data set. For a detailed depiction of the patient selection process, see Figure 1.

Figure 1: Flow chart demonstrating selection of patients who underwent reversal of Hart­

mann’s procedure or comparable surgeries, between February 2010 and August 2019. HA: Hartmann’s procedure.

Table 1: Index operations, surgical indications and frequency of acute surgical management in

patients undergoing Hartmann’s procedure or comparable surgeries, n = 42. All mentioned index operations are end colostomies. * indicates that the surgery was acute.

HA: Hartmann’s procedure, CRC: Colorectal cancer

Indication HA        Transverse colostomy Defunctioning sigmoidostomy

Amyloidosis 1* Anal cancer 1 Anastomotic leakage 3* 1* CRC 1 CRC (ileus) 7* 1* 1* CRC (perforation) 2* Colonic perforation 5* Diverticular disease 1 + 11* Ileus 1* Mb Crohn 1*

Ovarian cancer (ileus) 1*

Perianal abscess 1*

Rectal perforation 1*

Rectovaginal fistula 1

Shotgun wound 1*

Of the study population, 90,5% underwent Hartmann’s procedure to resolve an acute clinical situa­ tion. The most common surgical indications were malignancy (n=14), diverticular disease (n=12), colonic/rectal perforation (n=6), symptomatic anastomotic leakage (n=4) and other (n=6), see Table 1. Two out of four patients with anastomotic leakage were initially operated due to colorectal can­ cer. Most patients were left with an end sigmoidostomy (n=38) following Hartmann’s procedure, while end transverse colostomy (n=4) was uncommon.

Pre­ and perioperative details

Median age at stoma reversal was 64 years, the proportion of males was 60%, median BMI was 27. At the time of surgery 19,0% of patients were current smokers and 85,7% of patients were classified as ASA 1 or ASA 2. Median operation time was 202 minutes, and perioperative bleeding 100 ml. Details regarding patient demographics and perioperative details are presented in Table 2 and Table 3, respectively.

Table 2: Demography of patients undergoing colostomy reversal following Hartmann’s procedure

(n=42). Values correspond to median (range) or percent (quota). Hb: hemoglobin

Variable Median/Percent Range/Quota

Age 64 (27­85) Males 59.5% (25/42) BMI 27 (18­43) ASA     I  16.7% (7/42)     II  69.0% (29/42)     III  14.3% (6/42)     IV  0.0% (0/42) Cancer stage 38.1% (16/42)     I 12.5% (2/16)     II 56.2% (9/16)     III 18.8% (3/16)     IV 12.5% (2/16) Smoking 19.0% (8/42) Hb 139 (110­183) Creatinine 76 (47­193)

Table 3: Peri­ and postoperative details in patients undergoing colostomy reversal following Hart­

mann’s procedure (n=42). Values correspond to median (range) or percent (quota).

Variable Median/Percent Range/Quota

Stoma reversed ≤ 6 months 11.9% (5/42) Stoma reversed > 6 months 88.1% (37/42) Laparoscopic reversal 4.8% (2/42) Operation time, min 202 (92­520)

Bleeding, ml 100 (0­2200)

Hospital stay, days 6 (3­18) Readmission ≤ 30 days 16.7% (7/42) Readmission 31­90 days 0.0% (0/42) Reoperation ≤ 30 days 7.1% (3/42) Reoperation 31­90 days 2.4% (1/42) Mortality ≤ 90 days 0.0% (0/42)

Median time to reversal and reasons for delayed stoma reversal were separately analyzed based on the surgical indication being malignant or not. In patients with malignancy, median time to reversal was 16 months, compared to 10 months in the non­malignant group. Combined, median time to stoma reversal was 12 months, with a range of 2­41 months. Distribution of stoma reversals over time can be viewed in Figure 2.

1

2

3

4

5

6

7

8

> 8

Time (quarters)

0

1

2

3

4

5

6

7

8

Number of patients

Figure 2: Distribution of stoma reversals in quarters following Hartmann’s procedure (n=42).

Stoma reversals at > 8 quarters included reversal at 25, 26, 28 and 41 months.

A total of 11,9% of stomas were reversed within 6 months and thus defined as in time. Remaining 88,1% were deemed delayed reversals. Only a small difference was noted between the malignant (12,5%) and non­malignant groups (11,5%).

Adjuvant chemotherapy was the leading cause (64,3%) of delay in patients with malignancy. Com­ bined, all medically motivated delays accounted for 78,5% in this group, leaving 21,4% of patients with no health­related reason explaining the delay (Figure 3). In contrast, only 26,1% of delays were medically motivated in patients without malignancy as surgical indication. In the majority (56,5%) of cases no health­related reason explaining the delay could be identified. The remaining 17,4% were due to the patient’s choice (Figure 4).

Adjuvant chemotherapy: 9 (64.3%) No health related reason: 3 (21.4%) Surgical procedures: 2 (14.3%)

Figure 3: Reasons for delayed stoma reversal (> 6 months), in patients operated with

Hartmann’s procedure due to malignant surgery indications, n = 14.

Surgical procedures: complication with perianal fistula, hip replacement surgery.

No health related reason: 13 (56.5%) Surgical procedures: 5 (21.7%) Patient's choice: 4 (17.4%)

Non-surgical complication: 1 (4.3%)

Figure 4: Reasons for delayed stoma reversal (> 6 months), in patients operated with

Hartmann’s procedure due to non­malignant surgery indications, n = 23.

Surgical procedures: complication with enterocutaneous fistula, surgery for hepatic artery aneurysm, hip replacement surgery, unfit due to adhesions, unhealed rectovaginal fistula. Non­surgical complication: abscess.

Postoperative course

Median hospital stay after reanastomosis was 6 days. One in three patients (35,7%) were treated with antibiotics beyond prophylaxis. Unplanned readmission within 30 days occurred in 16,7% of cases. Reasons for readmission were abscess formation (n=3), ileus (n=2), rectal bleeding (n=1) and malnutrition (n=1). The rate of reoperation within 30­days was 7,1%, caused by symptomatic anastomotic leakage (n=2) and postoperative bleeding (n=1). Reoperation between postoperative day 31­90 occurred in 2,4% of cases, the reason being surgery for ovarian cancer (n=1). No deaths occurred during the 90­day postoperative period.

Postoperative complications were common in our study population, 64,3% of patients (n=27) ended up with at least one complication and 28,6% (n=12) had multiple complications. Early complica­ tions were anastomotic leakage (n=2), abscess formation (n=6), wound infection (n=8), ileus (n=7), paresthesia (n=2) and oral candidiasis (n=2), among others. Incisional hernia (n=8) was the most frequent late complication followed by subileus (n=2). These as well as other less frequent com­ plications can be viewed in Tables 4­5.

Three patients received a loop ileostomy in association with reversal surgery to relieve the colorectal anastomosis, these were reversed after 98, 122 and 142 days respectively. In addition, two patients were reoperated as a result of symptomatic anastomotic leakage, they each received a permanent colostomy.

Table 4: Early postoperative complications (median ≤ 30 days) following reversal of Hartmann’s

procedure. Median: median time (days) to onset of complication. Range: minimum to maximum number of days to onset of complication, described when ≥ 2 patient suffered the complication.

Complication Quota Median Range

Anastomotic leakage (2/42) 4 (3­5) Abscess (6/42) 11 (4­1030) Wound infection (8/42) 10 (4­35) Urinary tract infection (1/42) 6

Oral candidiasis (2/42) 12 (12­13) Hemorrhage (1/42) 5

Rectal bleeding (1/42) 18 Acute renal failure (1/42) 2

Ileus (7/42) 14 (3­2350)

Malnutrition (1/42) 25 Bile acid malabsorption (1/42) 7

Paresthesia (2/42) 0 (0­0) Erectile dysfunction (1/42) 0

Wound dehiscence (1/42) 2 Chipped tooth (1/42) 0

Table 5: Late postoperative complications (median > 30 days) following reversal of Hartmann’s

procedure. Median: median time (months) to onset of complication. Range: minimum to maxi­ mum number of months to onset of complication, described when ≥ 2 patient suffered the compli­ cation.

Complication Quota Median Range

Anastomotic stricture (1/42) 4 Enterocutaneous fistula (1/42) 6 Subileus (1/42) 6 Incisional hernia (8/42) 11 (5­51) Fecal incontinence (1/42) 12 Rectal prolapse (1/42) 28

Discussion

A major discovery was that only 12% of patients underwent stoma reversal following Hartmann’s procedure within 6 months. Correspondingly, the vast majority (88%) of patients had a delayed stoma reversal. Both Roe­ and Wigmore et al presented reanastomosis rates of ≥ 80% within 6 months, far from our results [14, 15].

Results demonstrating a delayed reversal was not unexpected, since similar research conducted at our institution has reported comparable results, in regard to reversal of other stoma types [20, 21]. However, the extent of the delay was somewhat surprising. The present study displayed a median time to reversal of 12 months, comparing to a median time ranging from 3­11 months, in previous research reviewing reversal of Hartmann’s procedure [15, 16, 14, 17, 9, 18, 8, 2].

Stoma reversal in cancer patients was not delayed more often than in patients with other surgical indications, however they displayed a greater delay (median 16 months).

Adjuvant chemotherapy caused delayed reversals in over six out of ten cancer patients. But the delay often sustained longer than what could solely be justified by treatment with chemotherapy. In the non­malignant group, only 26% of delays were medically motivated, accordingly no health­ related reason could be identified in the majority (57%) of cases. We interpret this as being a

consequence of limited surgical capacity, where elective reversal of Hartmann’s procedure is given a low priority compared to other procedures. It appears, no previous report has investigated causes for delayed Hartmann’s reversal. Albeit recently, Horesh et al described a pattern of delaying rever­ sal in aged, females and diabetic patients [9]. An additional publication from Resio et al. revealed an association between socioeconomic status and time to reversal [16]. Further research must be conducted at a larger scale, to better understand what factors contributes to a delayed stoma reversal in these patients.

The present study also reviewed postoperative outcome following reversal of Hartmann’s proce­ dure. As many as 64% of patients had at least one complication, confirming that the operation involves a high risk of postoperative morbidity. The aforementioned compares to a morbidity rate, ranging from 14­55% in previous literature [22, 23, 24]. Worth noting is that the lower end of the spectrum is represented by articles examining laparoscopic reversal of Hartmann’s procedure [22, 17], while open surgery is the standard approach at our institution. Only 2 out of 42 surgeries were done laparoscopically, possibly contributing to a higher frequency of postoperative compli­ cations. Moreover, an extensive follow up time and difficulties determining causality between reversal surgery and subsequent medical events meant including a number of complications that couldn’t with certainty be linked to the operation, nor ruled out. This likely added to the morbidity rate but was the preferred option when weighed against a risk of introducing considerable selection bias, to an already subjective record review, if some complications were to be excluded.

In agreement with previous literature, wound infection was the most frequent complication at 19% (alongside incisional hernia), a rate comparable to what has been demonstrated in other series (4,9­ 30%) [25, 23]. Seventeen percent of patients suffered at least one episode of postoperative ileus. Yang et al demonstrated a distinct difference in the frequency of ileus based on surgical approach, with rates of 17% using open surgery, compared to 2% with the laparoscopic technique [22]. Results in line with others were observed in regard to the frequency of reoperation (10%) and symptomatic anastomotic leakage (5%) [9, 8, 25]. Continuing on a positive note, no patients died during the 90­day postoperative course, while a mortality rate of 0­4% has been recognized in other studies [13, 3].

patients to make informed decisions when deciding on stoma reversal surgery. The open surgery approach was applied in almost all cases of stoma reversal, even with the laparoscopic technique being a feasible option that has been used in the context of colorectal surgery at our clinic, since 2006. In an effort to reduce complications, reversal of Hartmann’s procedure could be considered as an additional area of application for the laparoscopic approach.

Strengths and limitations

Some aspects of this study limit the generalizability of the results. Specific limitations were the relatively small study population and the single­center setting. The number of patients included in the study turned out smaller than first anticipated, since multiple patients included in the primary chart review had undergone a type of stoma reversal surgery not considered comparable to reversal of Hartmann’s procedure. A further limitation was the retrospective nature of the study, where data was subjected to interpretation by the reviewer.

A strength of the current study was its population­based design, including all patients undergo­ ing reversal of Hartmann’s procedure in Örebro County during a nine­year period. An additional advantage owes to high completeness of data, as the majority of variables included in the anal­ ysis were well documented and easy to access. All patient charts were reviewed by one person, providing a consistent assessment.

Conclusion

Almost 9 in 10 patients had a delayed stoma reversal, beyond 6 months after Hartmann’s procedure. No significant difference was seen between the malignant and non­malignant groups. However, median time interval between index operation and subsequent reversal was greater in patients with malignancy (16 months), as compared to other indications (10 months). The main cause of delay was adjuvant chemotherapy (64%) in the malignant group, while low priority within the healthcare system (57%) dominated in the non­malignant group. Postoperative morbidity was common, 64% of patients had at least one complication. Wound infection and incisional hernia were the most frequent, followed by ileus. Despite extensive use of the open surgery technique, and in contrast to the high frequency of postoperative morbidity, a mortality rate of zero was recognized.

Acknowledgement

I want to express a special thanks to my supervisor Peter Matthiessen at the Department of Surgery, Örebro University Hospital. Your guidance and encouragement made this project possible, for this I am beyond grateful.

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