Effect of submucosal epinephrine injection on local gastric blood flow. A study using laser Doppler flowmetry and reflectance spectrophotometry

Efficacy of Epinephrine Injection in Preventing Post-ERCP Pancreatitis

BACKGROUND

Rectal indomethacin or a topical spray of epinephrine to the papilla of Vater has each shown efficacy alone in the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We supposed that a submucosal epinephrine injection would be more effective and longer acting than a topical epinephrine spray and therefore would further reduce the incidence of PEP.

PATIENTS AND METHODS

A retrospective analysis was conducted of 412 patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) between January 2017 and December 2019. These patients were divided into 2 groups: the indomethacin group and the indomethacin plus the submucosal epinephrine injection group. The incidence rates and severity of PEP, post-ERCP hyperamylasemia, other outcomes, and any other adverse events were compared between the groups.

RESULTS

Baseline demographic and clinical characteristics and procedure-related parameters were similar between the 2 groups. The incidence of PEP was 0.4% in the epinephrine group compared with 5.1% in the indomethacin group (P<0.001). Post-ERCP hyperamylasemia occurred in 24.6% of patients in the indomethacin group, whereas 7.6% of patients in the epinephrine group developed this condition; the difference was significant (P<0.001). Postsphincterotomy bleeding occurred in 5 patients, all of whom were in the indomethacin group (P<0.001). Other adverse events, including arrhythmias, acute coronary events, stroke, or hypertension were not significantly different between the 2 groups.

CONCLUSION

Addition of a submucosal epinephrine injection in conjunction with rectal indomethacin significantly reduced the incidence of PEP, post-ERCP hyperamylasemia, and postsphincterotomy bleeding.

Electrochemical preparation of surface molecularly imprinted poly(3-aminophenylboronic acid)/MWCNTs nanocomposite for sensitive sensing of epinephrine

A nanocomposite with multi-walled carbon nanotubes (MWCNTs) coated with surface molecularly imprinted polymers (MIPs) poly(3-aminophenylboronic acid) (PAPBA) was successfully prepared via potentiodynamic electropolymerization and tested as an effective electrochemical material for epinephrine (EP) detection. The morphology and properties of the sensing material were characterized with scanning electron microscopy and electrochemical impedance spectroscopy. Compared with MWCNTs or non-imprinted polymers PAPBA modified MWCNTs electrodes, the PAPBA(MIPs)/MWCNTs modified electrode showed a lower charge transfer resistance and enhanced electrochemical performance for EP detection. The improved performance can be attributed to the large amount of specific imprinted cavities with boric acid group which can selectively adsorb EP molecule and the synergistic effect between MWCNTs and PAPBA(MIPs). The effects of pH, the molar ratio between monomer and template molecule, the cycle number of electropolymerization, and the accumulation time of the modified electrode on the sensing performance were investigated. It was found that under the optimal conditions, the PAPBA(MIPs)/MWCNTs sensor could effectively recognize EP from many possible interferents of higher concentration within a wide linear range of 0.2-800 μmol·L^-1, with low detection limit of 35 nmol·L^-1, high sensitivity and good discrimination. The detection of EP in human serum and real injection samples using the PAPBA(MIPs)/MWCNTs sensor also gave satisfactory results.

Distinctive aspects of peptic ulcer disease, Dieulafoy's lesion, and Mallory-Weiss syndrome in patients with advanced alcoholic liver disease or cirrhosis

AIM: To systematically review the data on distinctive aspects of peptic ulcer disease (PUD), Dieulafoy’s lesion (DL), and Mallory-Weiss syndrome (MWS) in patients with advanced alcoholic liver disease (aALD), including alcoholic hepatitis or alcoholic cirrhosis.

METHODS: Computerized literature search performed via PubMed using the following medical subject heading terms and keywords: “alcoholic liver disease”, “alcoholic hepatitis”,“ alcoholic cirrhosis”, “cirrhosis”, “liver disease”, “upper gastrointestinal bleeding”, “non-variceal upper gastrointestinal bleeding”, “PUD”, ‘‘DL’’, ‘‘Mallory-Weiss tear”, and “MWS’’.

RESULTS: While the majority of acute gastrointestinal (GI) bleeding with aALD is related to portal hypertension, about 30%-40% of acute GI bleeding in patients with aALD is unrelated to portal hypertension. Such bleeding constitutes an important complication of aALD because of its frequency, severity, and associated mortality. Patients with cirrhosis have a markedly increased risk of PUD, which further increases with the progression of cirrhosis. Patients with cirrhosis or aALD and peptic ulcer bleeding (PUB) have worse clinical outcomes than other patients with PUB, including uncontrolled bleeding, rebleeding, and mortality. Alcohol consumption, nonsteroidal anti-inflammatory drug use, and portal hypertension may have a pathogenic role in the development of PUD in patients with aALD. Limited data suggest that Helicobacter pylori does not play a significant role in the pathogenesis of PUD in most cirrhotic patients. The frequency of bleeding from DL appears to be increased in patients with aALD. DL may be associated with an especially high mortality in these patients. MWS is strongly associated with heavy alcohol consumption from binge drinking or chronic alcoholism, and is associated with aALD. Patients with aALD have more severe MWS bleeding and are more likely to rebleed when compared to non-cirrhotics. Pre-endoscopic management of acute GI bleeding in patients with aALD unrelated to portal hypertension is similar to the management of aALD patients with GI bleeding from portal hypertension, because clinical distinction before endoscopy is difficult. Most patients require intensive care unit admission and attention to avoid over-transfusion, to correct electrolyte abnormalities and coagulopathies, and to administer antibiotic prophylaxis. Alcoholics should receive thiamine and be closely monitored for symptoms of alcohol withdrawal. Prompt endoscopy, after initial resuscitation, is essential to diagnose and appropriately treat these patients. Generally, the same endoscopic hemostatic techniques are used in patients bleeding from PUD, DL, or MWS in patients with aALD as in the general population.

CONCLUSION: Nonvariceal upper GI bleeding in patients with aALD has clinically important differences from that in the general population without aALD, including: more frequent and more severe bleeding from PUD, DL, or MWS.

Therapeutic endoscopy for acute upper gastrointestinal bleeding

Endoscopy is the primary diagnostic and therapeutic tool for upper gastrointestinal bleeding (UGIB). The performance of endoscopic therapy depends on findings of stigmata of recent hemorrhage (SRH). For peptic ulcer disease-the most common etiology of UGIB-endoscopic therapy is indicated for findings of major SRH, such as active bleeding, oozing, or the presence of a nonbleeding visible vessel, but not indicated for minor SRH, such as a pigmented flat spot or a simple ulcer with a homogeneous clean base. Endoscopic therapies include injection, ablation, and mechanical therapy. Monotherapy reduces the risk of rebleeding in patients with peptic ulcer disease with major SRH to about 20%. Combination therapy, especially injection followed by either ablation or mechanical therapy, is generally recommended to further reduce the risk of rebleeding to about 10%. Endoscopic dual hemostasis by an experienced endoscopist reduces the risk of rebleeding, the need for surgery, the number of blood transfusions required, and the length of hospital stay. This Review article comprehensively analyzes the principles, indications, instrumentation, techniques, and efficacy of endoscopic hemostasis.

Acute lower GI bleeding for the acute care surgeon: current diagnosis and management

Lower gastrointestinal bleeding is a common cause for hospital admission that results in significant morbidity and mortality. After initial resuscitation of the patient, the diagnosis and treatment of lower gastrointestinal bleeding remains a challenge for acute care surgeons. Identifying the source of bleeding can be difficult since many patients bleed intermittently or stop bleeding spontaneously. It is therefore important for the acute care surgeon to be familiar with the different diagnostic and therapeutic modalities and their advantages and disadvantages in order to guide the management of the acutely bleeding patient. This review summarizes the current methods available for the diagnosis and treatment of acute lower gastrointestinal bleeding and proposes an algorithm for the management of these patients.

Acute nonvariceal upper gastrointestinal bleeding: endoscopic diagnosis and therapy

Acute upper gastrointestinal bleeding is a relatively common,potentially life-threatening condition that causes more than 300,000 hospital admissions and about 30,000 deaths per annum in America. Esophagogastroduodenoscopy is the procedure of choice for the diagnosis and therapy of upper gastrointestinal bleeding lesions. Endoscopic therapy is indicated for lesions with high risk stigmata of recent hemorrhage, including active bleeding, oozing, a visible vessel, and possibly an adherent clot. Endoscopic therapies include injection therapy, such as epinephrine or sclerosant injection; ablative therapy, such as heater probe or argon plasma coagulation; and mechanical therapy, such as endoclips or endoscopic banding. Endoscopic therapy reduces the risk of rebleeding,the need for blood transfusions, the requirement for surgery, and patient morbidity.

Pilot studies to demonstrate that intestinal mucosal afferent nerves are functionally linked to visceral adipose tissue

Dietary capsaicin reduces rodent visceral fat weight. We tested the hypothesis that intact intestinal mucosal afferent nerve function is necessary for fat deposition in visceral adipose tissue sites. Rats were treated daily for 2 weeks with intragastric (chronic treatment) vehicle or capsaicin. Superior mesenteric artery blood flow and mesenteric and inguinal fat blood flow were measured before and after capsaicin was administered into the duodenum (acute treatment). Fat from all sites was dissected and weighed. Chronic capsaicin significantly attenuated acute capsaicin-induced mesenteric hyperemia but did not abolish the reflex wiping of the eye exposed to capsaicin, indicating that functional ablation was limited to the intestinal mucosal afferent nerves. The associated vasoconstriction in adipose tissue was inhibited at the visceral (mesenteric) site and maintained but attenuated at the subcutaneous (inguinal) site. The onset of vasoconstriction was instantaneous, indicating a reflex mechanism. There was a redistribution of fat from visceral to subcutaneous sites, reflected by a decrease and an increase in the percentage of body fat in the visceral and subcutaneous sites, respectively. These pilot studies reveal for the first time that normal intestinal mucosal afferent nerve function is necessary for the physiologic accumulation of fat in visceral adipose tissue sites.

Endoscopic Hemostasis for Bleeding Gastric Stromal Tumors by Application of Hemoclip

In the past, numerous reports have advocated primary surgical resection as a treatment of choice for bleeding gastric stromal tumors (GIST). There were scarce reports on primary hemostasis with endoscopic therapy. We encountered two patients who presented to our unit with acute bleeding from gastric fundal stromal tumor, in whom we were able to achieved successful endoscopic hemostasis with hemoclip therapy. We describe the management of these cases and reviewed the current management strategies in bleeding gastric stromal tumor.

Randomized trial of normal saline solution injection versus bipolar electrocoagulation for treatment of patients with high-risk bleeding ulcers: is local tamponade enough?

BACKGROUND

Endoscopic injection of normal saline solution is reportedly an effective treatment for bleeding ulcers. If it is as effective as standard therapy, low cost, wide availability, and lack of injury would make saline solution injection an attractive option.

METHODS

Patients with clinical evidence of major bleeding from an ulcer with active bleeding or a nonbleeding visible vessel were randomly assigned to injection with normal saline solution (1-2 mL boluses; mean volume 30 mL) or bipolar electrocoagulation (20 W, 10-sec applications; mean time 100 sec). Patients, those caring for patients, and those collecting data were blinded to therapy.

RESULTS

Further bleeding occurred in 14 (29%) of 48 patients in the saline solution group versus 6 (12%) of 52 patients in the bipolar group (95% CI [2%, 33%]; p = 0.04). Significantly more units of blood were transfused in the saline solution group (median 2 units vs. 0 units; p = 0.01). Hospital days (median 4 vs. 3) and mortality (6% vs. 2%) were not significantly different in the 2 groups. Independent risk factors for further bleeding were saline solution injection (p = 0.02), units transfused before therapy (p = 0.02), and ulcer size (p = 0.03).

CONCLUSION

Local tamponade with saline solution injection is less effective than bipolar electrocoagulation for the treatment of bleeding ulcers.

Therapeutic endoscopy for nonvariceal gastrointestinal bleeding

This article reviews the role of therapeutic endoscopy in the diagnosis and treatment of nonvariceal upper and lower gastrointestinal (GI) hemorrhage. The initial approach to patients with GI bleeding is reviewed. Endoscopic treatment of various stigmata of recent peptic ulcer hemorrhage is discussed in detail. Management of less common causes of nonvariceal bleeding, such as Dieulafoy's lesions, Mallory-Weiss tears, angiomas, and bleeding colonic diverticula is described. Recommendations for endoscopic techniques are based on the results of UCLA-CURE hemostasis studies.

Management of gastrointestinal bleeding induced by gastrointestinal endoscopy

Therapeutic gastrointestinal endoscopy has a much greater risk of inducing gastrointestinal hemorrhage than diagnostic endoscopy. For example, colonoscopic polypectomy has a risk of approximately 1.6% of inducing bleeding, compared with a risk of approximately 0.02% for diagnostic colonoscopy. Higher-risk procedures include colonoscopic polypectomy, endoscopic biliary sphincterotomy, endoscopic dilatation, endoscopic variceal therapy, percutaneous endoscopic gastrostomy, and endoscopic sharp foreign body retrieval. The risk of inducing hemorrhage is decreased by meticulous endoscopic technique. Hemorrhage from endoscopy may be immediate or delayed. Immediate hemorrhage should be immediately treated by endoscopic hemostatic therapy, including injection therapy, thermocoagulation, or electrocoagulation. Delayed hemorrhage generally requires repeat endoscopy for diagnosis and for therapy, using the same hemostatic techniques.

Development and application of endoloops for the treatment of bleeding esophageal varices

BACKGROUND

Endoloops are detachable nylon snares. The aims of this study were to develop an endoscopic method for repeated delivery of endoloops to arrest variceal bleeding, to compare efficacy of endoloop hemostasis with injection and band ligation in experimental models of bleeding, and to test the reliability and safety of endoloops in a pilot study in patients with varices.

METHODS

Technical modifications including ridged endcaps and alterations in angulation of endoloops were developed to speed delivery and improve efficacy. Hemostatic efficacy of endoloops was compared with sclerotherapy and band ligation in animal studies before studies in patients.

RESULTS

Modified endcap and endoloops allowed repeated applications without withdrawal of the endoscope. Right-angled endoloops ensnared more (p < 0.0001) gastric tissue and were more reliable (p < 0.05) than straight endoloops. Injection therapy and prestretched bands appeared ineffective, whereas band ligation was only effective on vessels up to 2 mm in diameter. Only endoloops achieved hemostasis on vessels of 3 to 5 mm (p < 0.05). No significant complications occurred using endoloops in animal (esophagus n = 20, stomach n = 20) or human (n = 11) studies.

CONCLUSIONS

Endcap and endoloop modifications simplified repeated application to varices. Endoloops were more effective than injection or band ligation in experimental hemostasis and appeared safe and effective in patients.

Is endoscopic paravascular injection of sclerosing agents reasonable in the control of GI bleeding?

BACKGROUND

The pharmacologic response and microvascular effects associated with the endoscopic injection of sclerosing agents around vessels (paravascular injection) to stop bleeding from the digestive tract remain to be clarified.

METHODS

Using in vivo microscopy, we directly visualized submucosal microvessels of the rat stomach and intestine. We studied differences among sclerosing agents in thrombus formation and vascular diameter change that occur through a pharmacologic response and/or local compression after topical application or paravascular injection of the agents.

RESULTS

Except for absolute ethanol, topical application of the agents did not cause constriction or thrombi in either arterioles or venules. Polidocanol topical application and paravascular injection significantly dilated arterioles. Injecting ethanolamine oleate near venules constricted them the longest and most effectively, but vasoconstriction in arterioles was transient. Injecting absolute ethanol formed long-lasting thrombi and caused vasoconstriction in venules, but arteriole thrombi persisted no more than 3 minutes. The vascular response to thrombin did not significantly differ from that to physiologic saline.

CONCLUSION

The paravascular injection of ethanolamine oleate, because of its long-lasting vasoconstriction, or of absolute ethanol, because of its thrombogenic effect, is a valid therapeutic approach to treating venous bleeding. The efficacy of paravascular injection of sclerosing agents for treating acute arterial bleeding, however, is not supported in this experimental model.

Assessment of human colon cancer protein kinetics in vivo

BACKGROUND

Malignancies enlarge because protein synthesis exceeds the rate of breakdown; however, the specific protein kinetic pattern remains unknown. Determining in vivo protein kinetic rates for a tumor may be useful for quantifying individual responses to a specific therapy. The aim of this study was to assess whether the growth of tumors is related to an increase in protein synthesis or an inhibition of protein breakdown.

METHODS

Five patients (age, 59 +/- 3 years) with adenocarcinoma of the colon undergoing colonoscopy were studied. Tissue protein synthesis and breakdown rates were measured in vivo for both segments of colon cancer and adjacent normal-appearing colonic mucosa by using a primed, continuous infusion of 1(13)C leucine with tissue biopsy and quantitation of regional blood flow by laser Doppler flowmetry.

RESULTS

Segments of colon cancer had a significantly (p < 0.05) greater rate of protein synthesis as quantitated by both the fractional rate of protein synthesis (Ca 45.4% +/- 5.0%/day versus nl mucosa 35.7% +/- 3.1%/day; mean +/- SEM) and by the tissue synthesis rate (Ca 69.4 +/- 9.0 versus nl mucosa 51.6 +/- 5.2 mumol/L leucine/day/100 gm tissue). Regional blood flow was significantly elevated in the cancer (Ca 110.9 +/- 5.8 versus nl mucosa 91.2 +/- 2.9 ml/min/100 gm), which contributed to commensurate rates of tissue breakdown (Ca 28.6 +/- 2.0 versus nl mucosa 28.2 +/- 2.4 mumol/L leucine/day/100 gm).

CONCLUSIONS

These results illustrate that human colon cancers grow in vivo as a result of increases in protein synthesis. Furthermore, increases in regional blood flow limit the rate of tissue protein breakdown of colon cancer, thereby contributing to growth of the malignancy. These findings support the contention that therapeutic strategies aimed at negating this inherent increase in protein synthesis or limiting blood flow may effectively limit the growth of malignancies. This methodology may also provide an index for evaluating the effectiveness of future therapies aimed at reducing tumor growth for individual patients.

Prolonged evaluation of epinephrine and normal saline solution injections in an acute ulcer model with a single bleeding artery

BACKGROUND

Animal studies of epinephrine or normal saline solution injection for bleeding ulcers do not consistently demonstrate local tamponade effect.

METHODS

We studied the change of bleeding rates of 28 acute gastric ulcers with a single bleeding artery in 10 dogs. Four injections of 1 mL epinephrine 1:10000 at 1 mm from the spurting artery (n = 7) were compared to four injections of normal saline solution 1 to 5 mL (n = 12) and to four dry needle sticks (n = 9). Bleeding rates were measured at initial arterial incision and at minutes 1, 5, 10, 15, 20, 25, and 30 after treatment.

RESULT

Reductions in early blood loss to 24.3% +/- .05 of baseline occurred with saline solution, to 17.7% +/- .03 with epinephrine, and to 66.0% +/- 1.8 in controls (p < .05 for epinephrine and saline solution vs control). A tendency for saline solution injected ulcers to resume bleeding was identified, with late blood loss increasing to 26.9% +/- .05 of baseline, (saline solution vs control) compared to 7.7% +/- .02 in epinephrine injected ulcers (p < .05 vs control).

CONCLUSIONS

The early acute hemostatic effect of injection therapy depends on local tamponade. The prolonged hemostatic effect is a combination of tamponade and vasoconstriction, with advantage of epinephrine over saline solution.

Thirteenth Gaddum Memorial Lecture. Neuronal and endothelium-derived mediators in the modulation of the gastric microcirculation: integrity in the balance

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Fibroblast growth factor in gastroprotection and ulcer healing: interaction with sucralfate

The study was designed to determine the gastroprotective and ulcer healing efficacy of basic transforming growth factor (bFGF) and to assess whether this peptide contributes to the action of sucralfate on the rat stomach. Application of human recombinant bFGF (1-100 micrograms/kg/hour subcutaneously) failed to affect the formation of acute gastric lesions induced by 100% ethanol and acidified aspirin but reduced the stress induced by gastric lesions. Sucralfate (100-200 mg/kg given orally) protected gastric mucosa against the ethanol, aspirin, and stress induced acute gastric lesions but the addition of bFGF (100 micrograms/kg subcutaneously or intragastrically) failed to affect sucralfate induced protection against ethanol or aspirin but increased that against stress. Administration of bFGF (3-300 micrograms/kg/day) by an intragastric or an intraperitoneal route or sucralfate (400 mg/kg/day) orally to rats with acetic acid induced gastric ulcers, enhanced the healing rate of these ulcers during seven day treatment in a dose dependent manner. This was accompanied by a pronounced increase in the number of capillaries and myofibroblasts and in DNA synthesis and DNA and RNA concentrations in the granulation tissue in the ulcer area. [125I]bFGF (1 microCi) applied subcutaneously or intragastrically accumulated in two to threefold higher amounts in the ulcer area than in the intact mucosa, particularly in rats treated with sucralfate. Concurrent treatment with indomethacin (2 mg/kg intraperitoneally) delayed ulcer healing and reduced the binding of labelled bFGF to the ulcer area, angiogenesis, and DNA synthesis by sucralfate. Addition of [125I]bFGF to sucralfate at various pHs resulted in the coprecipitation of bFGF by sucralfate in a pH dependent manner from about 10% at pH 7.0 to 90% at pH 1.5. Thus bFGF shows little protective activity and is not essential for gastroprotection afforded by sucralfate but plays an important part in healing of gastric ulcers possibly due to its growth promoting and angiogenic actions.

Dopaminergic control of gastric mucosal blood flow in humans. A study with endoscopic laser Doppler flowmetry coupled with gastric submucosal drug injection

We studied the dopaminergic regulation of the gastric mucosal blood flow (GMBF) measured with an endoscopic laser Doppler flowmetry in 27 healthy volunteers. They were randomly assigned to receive an endoscopic gastric submucosal injection (0.5 ml) of physiological saline (control group, N = 10), 50 micrograms of dopamine (DA) hydrochloride (N = 8), and 500 micrograms of a DA antagonist, metoclopramide (MCP) (N = 9). The drugs were dissolved in the same saline volume (0.5 ml) as used in control group and were injected via the mucosal area where the baseline GMBF was measured and the postdose GMBF was monitored until 5 min postdose. There was no significant difference in the mean (+/- SEM) baseline laser Doppler signals among the control, DA, and MCP groups (92.6 +/- 9.3, 81.8 +/- 9.0 and 96.9 +/- 13.3 mV, respectively). In the control group, no significant postdose changes in the laser Doppler signals occurred until 5 min postinjection. In contrast, the DA group exhibited a significant (P < 0.05 or 0.01) increase in the laser Doppler signals at 2, 3, 4, and 5 min postdose (118.9 +/- 18.8, 128.5 +/- 16.9, 146.6 +/- 18.6, and 131.2 +/- 14.2 mV, respectively), whereas the MCP group exhibited a significant (P < 0.05 or 0.01) decrease in the signals at 4 and 5 min postdose (67.9 +/- 5.3 and 64.8 +/- 3.5 mV, respectively), as compared not only with the respective baseline values but also with those obtained from other two groups at the corresponding postinjection periods.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of hepatic collateral hemodynamics on gastric mucosal blood flow in patients with liver cirrhosis

The dependence of the gastric mucosal change in liver cirrhosis on the extrahepatic collaterals is still unknown. Therefore we studied the influence of these collateral hemodynamics on gastric mucosal blood flow and gastric mucosal lesions. The subjects were 23 cirrhotic patients and were divided into two groups by the findings of percutaneous transhepatic portography. The first group consisted of 14 cases whose extrahepatic collaterals were via esophageal varices (group I). The second group included 9 cases having collaterals other than esophageal varices (group II). Multiple red spots were observed in 13 of 14 cases in group I, and two of nine cases in group II. Gastric mucosal blood flow was 2.0 +/- 0.9 volts (mean +/- SD) in group I, 4.0 +/- 1.2 in group II. A statistically significant difference was observed between groups I and II. Gastric mucosal blood flow was not significantly correlated with portal venous pressure in group I. It is concluded that, in liver cirrhosis, gastric mucosal blood flow is changeable according to the types of the extrahepatic collaterals.