Anisodamine restores bowel circulation in burn shock

Anisodamine hydrobromide in the treatment of critically ill patients with septic shock: a multicenter randomized controlled trial

BACKGROUND

Septic shock is the development of sepsis to refractory circulatory collapse and metabolic derangements, characterized by persistent hypotension and increased lactate levels. Anisodamine hydrobromide (Ani HBr) is a Chinese medicine used to improve blood flow in circulatory disorders. The purpose of this study was to determine the therapeutic efficacy of Ani HBr in the treatment of patients with septic shock.

METHODS

This was a prospective, multicenter, randomized controlled trial focusing on patients with septic shock in 16 hospitals in China. Patients were randomly assigned in a 1:1 ratio to either the treatment group or the control group. The primary endpoint was 28-day mortality. The secondary outcomes included 7-day mortality, hospital mortality, hospital length of stay, vasopressor-free days within 7 days, etc. These indicators were measured and collected at 0, 6h, 24h, 48h, 72h and 7d after the diagnosis.

RESULTS

Between September 2017 and March 2021, 404 subjects were enrolled. 203 subjects received Ani HBr and 201 subjects were assigned to the control group. The treated group showed lower 28-day mortality than the control group. Stratified analysis further showed significant differences in 28-day mortality between the two groups for patients with a high level of illness severity. We also observed significant differences in 7-day mortality, hospital mortality and some other clinical indicators between the two groups.

CONCLUSION

Ani HBr might be an important adjuvant to conventional treatment to reduce 28-day mortality in patients with septic shock. A large-scale prospective randomized multicenter trial is warranted to confirm our results.

Anisodamine hydrobromide ameliorates cardiac damage after resuscitation

The microcirculation is correlated with the prognosis of patients with cardiac arrest and changes after resuscitation. In the present study, the effects of anisodamine hydrobromide (AH) on microcirculation was investigated and its potential mechanisms were explored. A total of 24 pigs were randomly grouped into three groups (n=8): Sham, Saline and AH group. After pigs were anesthetized, intubated and mechanically ventilated, ventricular fibrillation was induced by electrical stimulation. After 8 min, cardiopulmonary resuscitation was given to the restoration of spontaneous circulation (ROSC). Arteriovenous blood was collected at baseline and 0, 1, 2, 4 and 6 h after ROSC to measure blood gas and cytokines. Perfused vessel density (PVD) and microvascular flow index (MFI) were measured to reflect the microcirculation. Continuous cardiac output and global ejection fraction were measured to indicate hemodynamics. Compared with Sham group, PVD and MFI in the intestines and the sublingual regions decreased significantly after resuscitation. The microcirculation recovered faster in the AH group than the SA group. The decrease of intestinal microcirculatory blood flow was closely related to the decrease of sublingual microcirculatory blood flow. The cardiac function was impaired after resuscitation, and a decrease of IFN-γ as well as IL-2 and an increase of IL-4 as well as IL-10 suggested the immune imbalance. The microcirculation changes in sublingual regions were closely related to the changes in intestines. AH could improve the immune imbalance after resuscitation and was beneficial to the recovery of cardiac function.

Current consensus and controversies in major burns management

Most doctors in Britain receive some training in the care of the burned patient, if not as an undergraduate then as part of training in accident and emergency medicine or in the Advanced Trauma Life Support (ATLS®) course. Because major burn injury presents infrequently to the average district hospital, most of this training is rusty by the time it is needed. Further, most have little opportunity to catch up with developments in this very specialized area of trauma medicine.

This paper aims to address some of these shortcomings by describing recent advances in burn care and highlighting areas of current debate. The fluids used for resuscitation, improved options for treatment, the status of ongoing discussions about treatment facilities and the state of the art in managing smoke inhalation are reviewed. Some pointers to the future and to avenues for research are suggested.

Establishment, Culture, and Scale-up of Brugmansia candida Hairy Roots for the Production of Tropane Alkaloids

Brugmansia candida (syn. Datura candida) is a South American native plant that produces tropane alkaloids. Hyoscyamine, 6β-hydroxyhyoscyamine (anisodamine), and scopolamine are the most important ones due to their anticholinergic activity. These bioactive compounds have been historically and widely applied in medicine and their demand is continuous. Their chemical synthesis is costly and complex, and thereby, these alkaloids are industrially produced from natural producer plants. The production of these secondary metabolites by plant in vitro cultures such as hairy roots presents certain advantages over the natural source and chemical synthesis. It is well known that hairy roots produced by Agrobacterium rhizogenes infection are fast-growing cultures, genetically stable and able to grow in hormone-free media. Additionally, recent progress achieved in the scaling up of hairy root cultures makes this technology an attractive tool for industrial processes. This chapter is focused on the methods for the induction and establishment of B. candida hairy roots. In addition, the scaling up of hairy root cultures in bioreactors and tropane alkaloid analysis is discussed.

Beneficial effects of anisodamine in shock involved cholinergic anti-inflammatory pathway

Anisodamine, an antagonist of muscarinic receptor, has been used therapeutically to improve blood flow in circulatory disorders such as septic shock in China since 1965. The main mechanism of anisodamine for anti-shock proposed in Pharmacology for Chinese medical students is to improve blood flow in the microcirculation. Here, we suggest a new mechanism for its anti-shock effect. That is, anisodamine, by blocking muscarinic receptor, results in rerouting of acetylcholine to α7 nicotinic acetylcholine receptor (α7nAChR) bringing about increased acetylcholine-mediated activation of α7nAChR and the cholinergic anti-inflammatory pathway.

Effect of carbachol on intestinal mucosal blood flow, activity of Na+-K+-ATPase, expression of aquaporin-1, and intestinal absorption rate during enteral resuscitation of burn shock in rats

We investigated the effect of carbachol (CAR, a cholinergic agent) on intestinal mucosal blood flow (IMBF), activity of Na-K-ATPase, expression of aquaporin (AQP)-1, and intestinal absorption rate during enteral resuscitation of a 35%TBSA scald in rats with a glucose electrolyte solution (GES). One hundred male Wistar rats were randomly divided into five groups: sham scald (N group); scald without fluid resuscitation (S group); scald resuscitated with enteral GES alone (GES group); scald resuscitated with enteral CAR alone (CAR group); and scald resuscitated with enteral CAR plus GES (GES/CAR group). The rats were inflicted 35%TBSA third degree of scald injury on the back with boiling water (100 degrees C, 15 seconds) in all groups, except the sham scald group. A catheter was inserted into the proximal duodenum (5 cm distal to pylorus) and distal ileum (5 cm proximal to cecum), of each rats through laparotomy, thus a segment of intestine was virtually isolated to form a loop for inlet and outlet of introduced fluid. In N, GES, and GES/CAR groups, fluids were introduced 30 minutes after scald injury. The speed of fluid infusion was 4 ml/kg/1%TBSA for 4 hours. CAR (60 microg/kg) was injected into the intestinal lumen at 30-minute after injury in CAR and GES/CAR groups. At 2 and 4 hours after scald, intestinal absorption rate of water and Na, and IMBF were determined, respectively. Then, animals were killed, and specimens of intestinal tissue were obtained for the determination of the activity of Na-K-ATPase, hematoxylin-eosin coloring, and expression of AQP-1. The intestinal absorption rate was reduced markedly in GES group compared with sham scald group at 2 and 4 hours after scald, and absorption rate of small intestine in GES/CAR was significantly higher than that in GES group (P < .05). It was also found that there was significant decrease in IMBF, activity of Na-K-ATPase, and expression of AQP-1 in scald group compared with the sham group. However, in GES/CAR group, the levels of these parameters were significantly increased compared with scald groups (P < .05). The results indicate that CAR promotes intestinal absorption rate of water and Na by improving IMBF, ATPase activity, and AQP-1 expression in gut mucosa during resuscitation with enteral GES of burn shock in rats.

“Systemic apoptotic response” after thermal burns

The systemic pathophysiologic changes following thermal injuries affect multiple organs and body systems leading to clinical manifestations including shock, intestinal alterations, respiratory and renal failure, immunosuppression and others. Recent advances in the comprehension of mechanisms underlying systemic complications of thermal injuries have contributed to uncover part of the cellular and molecular basis that underlie such changes. Recently, programmed cell death (apoptosis) has been considered playing an important role in the development of such pathological events. Therefore, investigators utilizing animal models and clinical studies involving human primates have produced a large body of information suggesting that apoptosis is associated with most of the tissue damages triggered by severe thermal injuries. In order to draw the attention on the important role of apoptosis on systemic complications of thermal injuries, in this review we describe most of these studies, discuss possible cellular and molecular mechanisms and indicate ways to utilize them for the development of therapeutic strategies by which apoptosis may be prevented or counteracted.

The effects of anisodamine and dobutamine on gut mucosal blood flow during gut ischemia/reperfusion

AIM: To determine if anisodamine is able to augment mucosal perfusion during gut I/R ischemia-reperfusion.

METHODS: A jejunal sac was formed in Sprague Dawley rat. A Laser Doppler probe and a tonometer were inserted into the sac which was filled with saline. The superior mesenteric artery was occluded (SMAO) for 60 minutes followed by 90 minutes of reperfusion. At the end of 60 minutes of SMAO, either 0.2 mg/kg of anisodmine or dobutamine was injected into the jejunal sac. Laser Doppler mucosal blood flow and regional PCO₂ (PrCO₂) measurements were made.

RESULTS: Mucosal blood flow was significantly increased at 30, 60 and 90 minutes of reperfusion (R₃₀, R₆₀, R₉₀) when intraluminal anisodamine or dobutamine was present compared to intraluminal saline only (44 ± 3.3% or 48 ± 4.1% vs 37 ± 2.6% at R₃₀, 57 ± 5.0% or 56 ± 4.7% vs 45 ± 2.7% at R₆₀, 64 ± 3.3% or 56 ± 4.2% vs 48 ± 3.4% at R₉₀, respectively P < 0.05). Blood flow changes were also reflected by lowering of jejunal PrCO₂ measurements after intraluminal anisodamine or dobutamine compared with that of the saline controls (41 ± 3.1 mmHg or 44 ± 3.0 mmHg vs 49 ± 3.7 mmHg at R₃₀, 38 ± 3.7 mmHg or 40 ± 2.1 mmHg vs 47 ± 3.8 mmHg at R₆₀, 34 ± 2.1 mmHg or 39 ± 3.0 mmHg vs 46 ± 3.4 mmHg at R₉₀, respectively, P < 0.05). Most interesting finding was that there were significantly higher mucosal blood flow and lower jejunal PrCO₂ in anisodamine group than those in dobutamine group at 90 minutes of reperfusion (64 ± 3.3% vs 56 ± 4.2% for blood flow or 34 ± 2.1 mmHg vs 39 ± 3.0 mmHg for PrCO₂, respectively, P < 0.05), suggesting that anisodamine had a more lasting effect on mucosal perfusion than dobutamine.

CONCLUSION: Intraluminal anisodamine and dobutamine can augment mucosal blood flow during gut I/R and alleviate mucosal acidosis. The results provided benificial effects on the treatment of splanchnic hypoperfusion following traumatic or burn shock.

Monitoring tissue oxygenation during resuscitation of major burns

BACKGROUND

Because subcutaneous and splanchnic oxygenation indices are sensitive indicators of evolving hemorrhagic shock and adequacy of resuscitation, we postulated that these indices might have an equivalent role in the monitoring of severely burned patients. This observational study was undertaken to examine changes in tissue oxygenation indices during burn resuscitation.

METHODS

Seven patients with major burns (54 +/- 21% total body surface area) were studied during the first 36 hours of fluid resuscitation. Silastic tubing was placed in the subcutaneous tissue just beneath both normal skin and deep partial thickness burn. Fiberoptic sensors inserted into the tubing measured subcutaneous oxygen and carbon dioxide tensions in the burnt skin (PO2scb and PCO2scb) and normal skin (PO2scn and PCO2scn) continuously. Gastric intramucosal pH (pHi) and the mucosal CO2 (PCO2m) gap were calculated using gastric tonometers. Mean arterial pressure, arterial pH, lactate, and pHi measurements were obtained for 36 hours.

RESULTS

There were no significant differences in mean arterial pressure, arterial pH, or lactate concentrations throughout the study period, whereas indices of tissue oxygenation showed deterioration: pHi decreased from 7.2 +/- 0.1 to 6.7 +/- 0.3 (p = 0.06), the PCO2m gap increased from 12 +/- 17 to 108 +/- 123 mm Hg (p < 0.01), PO2scn decreased from 112 +/- 18 to 50 +/- 11 mm Hg (p < 0.01), PO2scb decreased from 62 +/- 23 to 29 +/- 16 mm Hg (p < 0.01), PCO2scn increased from 42 +/- 4 to 46 +/- 10 mm Hg (p = 0.2), and PCO2scb increased from 42 +/- 10 to 52 +/- 5 mm Hg (p = 0.05).

CONCLUSION

Despite adequate global indices of tissue perfusion after 36 hours of resuscitation, tissue monitoring indicated significant deterioration in the splanchnic circulation and in the normal and burnt skin.

Heparin-free hemodialysis in the treatment of hypernatremia in severely burned patients

BACKGROUND

Hypernatremia in severely burned patients is associated with high morbidity and mortality rates. As the causes of hypernatremia in major burn patients are still not clear, hemodialysis is the method of choice for the treatment. While hemodialysis is effective for the control of hypernatremia, it can cause bleeding complications that may be fatal for burn patients with extensive wounds and potential gastro-intestinal mucosal damage.

CLINICAL DATA

In the present study heparin-free hemodialysis in which the heparin is firmly absorbed to the haemofiltration membrane, hemophan, dispensed with systemic use of heparin. In two extensively burned patients with burn area of 100% TBSA and 98% TBSA respectively and hypernatremia with serum sodium concentration as high as 169 and 158 mmol/l respectively, heparin-free hemodialysis was performed five times and three times each.

RESULTS

Hypernatremia was satisfactorily corrected with no interference to the coagulation system in the two patients as indicated by clinical observation and biochemical analysis. The patient with burn area of 98% TBSA survived and the patient with burn area of 100% TBSA died of wound coverage failure 6 weeks after injury because of non-availability of autograft.

CONCLUSION

Heparin-free hemodialysis is an effective and safe method in the treatment of hypernatremia in extensively burned patients.