September 2020

Synopsis: Surgical management of low rectal cancer (rectal cancer <6cm from the anal verge) is variable. For patients in whom a 1-2cm distal resection margin is possible, an ultralow anterior resection with sphincter preservation is an option. These resections typically involve a stapled coloanal anastomosis, but hand-sewn anastomoses are performed when use of a stapler is not technically possible. Because of the high anastomotic leak rate associated with coloanal anastomoses, temporary fecal diversion is traditionally indicated. However, diverting stomas are associated with significant morbidity, including intestinal obstruction, dehydration and renal failure, and decreased quality of life. An alternative to the standard hand-sewn coloanal anastomosis (CAA) is the two-stage Turnbull-Cutait pull-through hand-sewn coloanal anastomosis (TCA), which allows for a sphincter preserving resection without fecal diversion. The first stage involves ultralow anterior resection with TME, followed by exteriorization of a 6-7cm segment of left colon through the anal canal (pull-through), which is kept in place by the resting pressure of the anal canal along with stitches fixing the colon to the perianal skin. Six to 10 days later, patients undergo the second stage during which a hand-sewn coloanal anastomosis is completed in the same fashion as that performed in the CAA. It is thought that scarring and adhesion formation between the left colon and the pelvis occurs during the interval between the first and second stage, allowing for the safe deferral of fecal diversion after anastomosis. Two systematic reviews have demonstrated low rates of anastomotic leaks and pelvic sepsis, low rates of stoma formation, and reasonably good functional outcomes for patients who undergo TCA for low rectal cancer.

This multicenter, randomized clinical trial primarily assessed the rates of 30-day overall postoperative morbidity between TCA (n = 46) and CAA (n = 46), with the hypothesis that morbidity would be lower in the TCA group due to the deferral of DLI. Postoperative functional outcomes and 1-year oncologic outcomes, including local recurrence (LR), distal recurrence (DR), disease-free survival (DFS) and overall survival (OS), were also assessed. For patients who underwent standard CAA, 30-day morbidity included the 30-day period both after their index resection and their ostomy reversal.

The results demonstrated no significant difference in overall 30-day postoperative morbidity between the two operations (45.7% with CAA versus 34.8% with TCA), although patients who underwent CAA did have a significantly higher rate of post-operative ileus development (24% with CAA versus none with TCA). Anastomotic leak rates were consistent between the two groups, being diagnosed in 24% of patients who underwent CAA compared to 13% of those who underwent TCA. Two patients in the TCA group required stoma creation secondary to post-operative colonic ischemia. Complications related to the stoma in the CAA group were low, with only 3 patients being readmitted for dehydration/renal failure due to high ileostomy output. At 1-year of follow up, all oncologic outcomes were similar between the two groups, and functional outcomes were comparable. 

While this trial failed to demonstrate a morbidity advantage with TCA over CAA as hypothesized, it did importantly show that TCA is comparable to CAA in regard to rates of postoperative complications, and short-term functional and oncologic outcomes. TCA is a safe alternative for patients with low rectal cancer amenable to sphincter preserving resection who wish to avoid DLI and its potential risks and complications.

Synopsis: On August 23, with the support of the White House, the FDA issued a controversial emergency authorization for the use of convalescent plasma to treat COVID-19. Several small trials have been conducted, including the results reported here by Salazar et al from Houston. However the recent authorization is based primarily on data from a large, pre-printed (yet to be peer-reviewed) study of 35,000 patients treated with plasma which will also be reviewed below.

Convalescent plasma therapy, in which plasma from a patient who has recovered from a disease is transfused into a symptomatic patient to provide passive antibody-mediated immunity, has been used in prior pandemics and is currently under investigation for COVID-19. Despite rigorous international investigations, an ideal treatment regimen for COVID-19 has yet to be defined. 

Twenty-five patients with severe or life-threatening COVID-19 at a single US center were treated with convalescent plasma. All patients were also receiving some combination of antiviral, antibacterial, and anti-inflammatory treatment. No adverse events linked to plasma transfusion occurred within 24 hours of transfusion. By day 7 after transfusion, 36% of patients improved from baseline while 12% had deteriorated. By day 14, 76% of patients improved clinically and one patient died. 

The authors of this study state that results are similar to recent outcomes after treating COVID-19 patients with Remdesivir. However, it is important to address that many of the patients in this study were receiving adjunctive therapies, including Remdesivir, which confounds any perceived additional benefit of convalescent plasma. In addition to limiting the impact of the conclusions, the small sample size in this study was unable to address several other variables. For example, it is unknown whether the IgG titers in the convalescent plasma correlate with efficacy after transfusion. Several patients received plasma with very low titers, of which one patient died and one was placed on ECMO. Additionally, this study was unable to assess the ideal timing of convalescent plasma treatment. 

The recent release of data from 35,000 COVID-19 patients who received plasma, while preliminary, does address these questions. The study suggests a mortality benefit for critically ill patients receiving convalescent plasma within three days of diagnosis. Additionally, it appeared that plasma with higher IgG titers did correlate with lower mortality rates. While this data is promising, more rigorous studies and peer review will be necessary to determine the efficacy of convalescent plasma as a potential therapy.

Synopsis: Gastrostomy tube placement is one of the commonly performed surgeries in the pediatric population. Due to the volume of these procedures performed, complications such as infection, granulation tissue, or accidental dislodgement are common. Disparities such as structural barriers may limit family’s ability to attend educational sessions or standard post-operative follow up. The aim of this study was to describe the association between socioeconomic status and subsequent complications in pediatric gastrostomy tubes.

The authors performed a single-center retrospective review from 2011 to 2016 identifying patients undergoing gastrostomy tube placement. Socioeconomic factors affecting care such as caregiver income, education, and employment status that are unable to be attained from the medical record were estimated using block level U.S Census data. This is a validated method using geocoding to identify census tracts that better describe the study population (e.g. median household income, unemployment rate, poverty level, proportion of those with high school diplomas, etc.) 

A total of 386 patient were included in the study. Most were white and English-speaking. Complications were common, with 69.9% of patients having at least one complication (61.2% were mechanical and 21.5% were unspecified). The odds of having a complication were four times greater for those paying with Medicaid or self-pay (uninsured). Additionally, there was a significant difference by census tract unemployment rate for patients with an additional complication: the unemployment rate was 23% higher in this group.

This study describes the association between socioeconomic factors and complications in pediatric gastrostomy tubes. Importantly, they used U.S. Census tract data, methodology from social epidemiology that has been applied less commonly in surgical specialties, and were able to show that socioeconomic factors such as payor status and unemployment levels were significantly associated with gastrostomy complications. Their study has limited generalizability due to the predominantly white, English-speaking population, and more rural location, but their methodology could be applied nationally.