Randomized Controlled Trial Comparing Liposomal to Plain Bupivacaine in the Transversus Abdominis Plane for DIEP Flap Breast Reconstruction

BACKGROUND

Pain control after autologous breast reconstruction is important for patient satisfaction and early recovery. Transversus abdominis plane (TAP) blocks are commonly used as part of an enhanced recovery after surgery (ERAS) pathway for breast reconstruction. It is uncertain whether liposomal bupivacaine used in TAP blocks offers additional advantages. This study aimed to compare the efficacy of liposomal bupivacaine versus plain bupivacaine for patients undergoing deep inferior epigastric perforator flap reconstruction.

METHODS

This double-blinded randomized controlled trial studied patients undergoing abdominally based autologous breast reconstruction between June of 2019 and August of 2020. Subjects were randomly assigned liposomal or plain bupivacaine, performed using ultrasound-guided TAP block technique. All patients were managed according to an ERAS protocol. Primary outcomes were postoperative narcotic analgesia required, measured in oral morphine equivalents from postoperative days 1 to 7. Secondary outcomes included numeric pain scale score on postoperative days 1 to 7, nonnarcotic pain medication use, time to first narcotic use, return of bowel function, and length of stay.

RESULTS

Sixty patients were enrolled: 30 received liposomal bupivacaine and 30 received plain bupivacaine. There were no significant differences in demographics, daily oral morphine equivalent narcotic use, nonnarcotic pain medication use, time to narcotic use, numeric pain scale score, time to bowel function, or length of stay.

CONCLUSION

Liposomal bupivacaine does not confer advantages over plain bupivacaine when used in TAP blocks for abdominally based microvascular breast reconstruction in patients under ERAS protocols and multimodal approaches for pain control.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, I.

Video-assisted transumbilical appendectomy in children

BACKGROUND

Video-assisted transumbilical appendectomy (VATA) is a combination of laparoscopic and open techniques and is not widely used in children. We are reporting our most recent experience with this technique.

METHODS

After the institutional review board approval, the charts of patients who underwent VATA between December 2003 and October 2004 were retrospectively reviewed. All children presenting with a preoperative diagnosis of appendicitis were candidates. A 10-mm trocar was placed in the umbilicus. An operating laparoscope was used for mobilizing the appendix. The appendix was delivered through the umbilicus. A standard extracorporeal appendectomy was performed. The umbilical ring was closed and the wound irrigated. Demographic and outcome data were collected and is presented as mean +/- SD.

RESULTS

Sixty-one males and 50 females underwent VATA (n = 111). Age and weight were 11 +/- 3.2 years and 49 +/- 22 kg, respectively. Six patients had previous abdominal surgery. Operative time was 36 +/- 24 minutes (range, 9-140 minutes). An additional trocar was placed in 2 patients, and 2 patients were converted to open. Five patients had additional procedures. Appendicitis was classified intraoperatively as acute (n = 44), suppurative (n = 5), gangrenous (n = 8), ruptured (n = 30), appendiceal colic (n = 13), and other (n = 11). Preoperative antibiotics were given to 95 patients and were continued in 35 patients postoperatively. Length of stay was 1.8 +/- 1.7 days (range, 1-11 days). Length of follow-up was 13 +/- 6.3 days (n = 90). Complications included intra-abdominal abscess (n = 1) and wound infection (n = 7).

CONCLUSIONS

Video-assisted transumbilical appendectomy minimizes equipment needs, thus, potentially reducing cost. Simple and complex appendectomies can be performed even if the patient has had previous abdominal surgery. Our complication rate was low, and our operating times and length of stay were short. Video-assisted transumbilical appendectomy is a safe and effective technique in children and can be used in lieu of the 3-trocar laparoscopic technique.

The use of estrogen, DHEA, and diosgenin in a sustained delivery setting as a novel treatment approach for osteoporosis in the ovariectomized adult rat model

It is well established that the pattern of bone loss from the cortex in osteoporotic bone begins from the endosteal surface of the cortex, where there is enlargement of the medullary canal at the expense of the inner cortex. Bone loss does not occur at the periosteal surface. The objective of the following study was to induce osteoporosis in female rats by ovariectomy, followed by treatment with sustained delivery of Diosgenin (DG), dehydroepiandrosterone (DHEA), or estrogen (E) after clinical signs of osteoporosis. Female Sprague Dawley rats were divided randomly into five groups containing four rats/group. Rats comprising group 1 were left intact and served as a control group. Animals in groups 2-5 were ovariectomized (OVX) and, after a 14 day delay to allow for induction of osteoporosis, were implanted with TCPL capsules containing DG, DHEA, and E, respectively. The experiment was ceased after 33 days of treatment, at which time the vital and reproductive organs for each group were collected, weighed, and analyzed histomorphometrically for differences. Further analysis of the progression of osteoporosis in the experimental animals was obtained by performing x-ray analysis of each group on a semi-weekly basis. By collecting and analyzing the femurs from each animal, we were also able to obtain important information about the histologic changes associated with osteoporosis (left femur), as well as data regarding the effects of osteoporosis on the mechanical strength of bone via three point bending analysis (right femur). The data generated by this study revealed important information as to the efficacy and safety of the alternative treatments DHEA, E, and DG for osteoporosis. First, histomorphometric analysis revealed that treatment with DHEA, E, and DG reduced the endosteal perimeter and cortical area to values very similar to controls (intact). Second, results of the bending stress and modulus in OVX and treated animals were not statistically different from the intact control animals, which suggests that the material properties of the bone were unaltered. Third, there is an increase in total body weight associated with OVX that is reduced to control levels after replacement therapy. Finally, OVX also resulted in reproductive tissue atrophy, which was reversed by all three of the treatment regimens in this study. These data suggest that bone loss after OVX can be significantly reduced by supplementation with sustained levels of DHEA, E, and DG without jeopardizing other body organs.

The prevention of osteoporotic progression by means of steroid loaded TCPL drug delivery systems

Numerous studies have suggested that there is a link between the age-related decreases in Estradiol and adrenal androgens, and the subsequent development of senile osteoporosis. The specific objectives of this investigation were: 1) to deliver Dehydroepiandrosterone (DHEA), Diosgenin (DG), and Estradiol (E) at sustained levels by Tri-Calcium Phosphate Lysine drug delivery systems (TCPL), and 2) to study the effects of the sustained delivery of DHEA, DG, and E on the bone turnover of adult female rats following withdrawal of the endogenous hormonal milieu by means of ovariectomization (OVX). In this study, 20 female Sprague-Dawley rats were randomly divided into five groups containing four rats per group. The rats in Group 1 served as intact controls. Animals in groups 2-5 were ovariectomized, and groups 3-5 were implanted immediately with TCPL drug delivery capsules containing DHEA, DG, and E, respectively. Group 2 served as the SHAM (OVX only) group. At the end of 33 days post implantation, the vital organs, reproductive organs, and femurs were collected and evaluated. Bone histomorphometric analyses as well as mechanical strength testing was performed. Data obtained from this study demonstrated that body weights were increased in all OVX animals, and that E replacement resulted in body weights that were not significantly different from intact controls. No differences were seen in the wet weights of any vital organs. However, a decrease in the weights of the cervix and oviducts were evident in all ovariectomized groups, with the exception of the E group. Thirty-three days following OVX, the OVX-only group exhibited an increased inner medullary area, decreased thickness of the cortical layer of bone, and decreased mechanical strength. The group treated with DHEA and the group treated with E were shown to maintain both the medullary area and the cortical thickness (as compared to the intact control group). The three point bending test of the femora showed that OVX-only induced a slight decline in mechanical strength, and that DHEA and DG, but not E, showed increases in mechanical strength. Results of this experiment suggest that DHEA and E may reduce bone remodeling as evidenced by the reduction in the medullary area, and that DHEA may possibly be used in postmenopausal patients to reduce osteoporotic progression.

TCPL drug delivery system: the effects of synthetic DHEA and Diosgenin using an ovariectomized rat model

Dehydroepiandrosterone (DHEA) has been shown in numerous studies to exhibit a host of benefits at the vital and reproductive organ levels. However, the use of naturally occurring DHEA is hindered by its inability to survive the first-pass metabolic process of the liver. One possible alternative means that deserves consideration is the administration of DHEA's precursor, namely, Diosgenin (DG). The specific objectives of this investigation were: 1) to deliver DHEA and DG at sustained levels by Tri-Calcium Phosphate Lysine (TCPL) drug delivery systems using ovariectomized (OVX) adult rats as a model, and 2) to evaluate the biochemical and histopathological changes associated with the sustained delivery of DHEA and DG. A total of 30 adult female rats were used in this investigation. The animals were further divided into 8 groups. Groups 1 and 2 animals served as intact control groups while each rat in groups 3-8 was ovariectomized (sham (33), n = 3 [group 3], sham (47), n = 4 [group 4]). Groups 5 and 6 were implanted with DHEA (group 5) and DG (group 6) loaded TCPL capsules immediately following the OVX procedure. Groups 7 and 8 were implanted with DHEA (group 7) and DG (group 8) loaded capsules 14 days following OVX. Surgical aseptic technique was employed according to standard laboratory protocols. Maliondialdehyde (MDA) and hormonal levels were measured from serum, collected semi-weekly, during the entire investigation (for 47 days) and X-rays were performed weekly. Pap smears were collected daily for 47 days to assess endometrial changes associated with DHEA and DG treatment. Following sacrifice (at day 33 for groups 1, 3, 5, and 6 and at day 47 for groups 2, 4, 7, and 8), routine H and E staining was conducted for histopathological evaluation of the reproductive and vital organs. Results of this investigation demonstrated: 1) OVX resulted in an increase in total body weight, and the use of DHEA and DG returned the body weight to near normal levels as compared to the intact control groups, 2) TCPL capsules delivered DHEA and DG at a sustained level during the 47 day study, 3) serum levels of MDA are as follows: DG > DHEA = OVX > control for the 33 day phase and OVX > DG > DHEA > control for the 47 day phase, 4) no significant changes were observed in total wet weights, as well as the morphology of the spleen, kidney, adrenal, heart, liver, and lung tissues, 5) OVX resulted in an atrophy and non-keratinization trend in the reproductive tissues, and sustained delivery of DHEA and DG showed no remarkable change in these tissues, 6) the use of sustained delivery of DHEA and DG resulted in higher weights of uteri compared to the OVX group. In conclusion, this study provided more information regarding the interrelationship between DHEA and DG, and the physiological responses encountered when they are administered continuously using the adult OVX rat as a model.