Haemodynamic patterns in patients with scorpion envenomation

Objective—To study cardiovascular haemodynamics following scorpion envenomation.
Setting—Intensive care unit of a university hospital.
Patients—Eight patients with Indian red scorpion (Mesobuthus tamulus) stings.
Intervention—Captopril (6.25 to 12.5 mg orally) every 30 minutes until pulmonary oedema resolved.
Main outcome measures—Haemodynamic data obtained by pulmonary artery catheterisation.
Results—Two haemodynamic patterns were seen. There was a predominant vascular effect in one patient, with severe hypertension, tachycardia, increased systemic vascular resistance index (SVRI = 5893 dyn.s.cm^-5), and normal cardiac index (2.73 l/m²). A predominant myocardial effect with left ventricular dysfunction and normal right ventricular function was seen in the other seven patients, with tachycardia, pulmonary oedema, mild hypotension, reduced stroke volume (mean (SD), 25.9 (8.3) ml/m²), normal SVRI (1812 (831) dyn.s.cm⁻⁵), and increased pulmonary artery wedge pressure (PAWP = 25 (4.4) mm Hg). Following mild dehydration pulmonary oedema subsided (PAWP = 14 (8.5) mm Hg) in three of these patients, but hypovolaemic shock developed (right atrial pressure (RAP) = 1.3 (2.1) mm Hg); pulmonary oedema recurred with rehydration. One patient developed fatal cardiogenic shock with raised PAWP (27 mm Hg) and RAP (11 mm Hg), and vasodilatation (SVRI = 1129 dyn.s.cm⁻⁵). Stroke volume (30.5 (8.7) ml/m²) and cardiac output (4.3 (1.5) l/m²) improved with resolution of pulmonary oedema (PAWP = 14.4 (4.2) mm Hg) following afterload reduction with captopril.
Conclusions—Mild envenomation causes severe vasoconstriction and hypertension. Severe envenomation produces predominant left ventricular dysfunction with normal systemic vascular resistance manifesting as pulmonary oedema or severe hypotension depending on the fluid balance. Shock due to biventricular dysfunction and vasodilatation occurs terminally.

Keywords: scorpion sting; myocarditis; pulmonary oedema; animal toxin     

Cardiac dysfunction and pulmonary edema following scorpion envenomation

Cardiac dysfunction with pulmonary edema following scorpion envenomation (SE) has been documented only in a few isolated case reports. We conducted a systematic hemodynamic study in five consecutive patients (mean age, 21.6 +/- 8 years) presenting with pulmonary edema occurring a few hours (9.6 +/- 5.2 hours) after SE. All patients had increased pulmonary capillary wedge pressure (mean, 25 +/- 1.8 mm Hg) while the systemic vascular resistance was elevated only in one. The stroke volume index was markedly depressed (21.7 +/- 3.6 ml/sq m) whereas cardiac index was normal or slightly decreased (2.5 +/- 0.4 L/min/sq m). Cerebral infarct and sudden cardiac arrest were the cause of death in two patients. In the three survivors, all the hemodynamic disturbances and respiratory abnormalities disappeared within a few days. We conclude that cardiac dysfunction was found in all five patients and this was reversible in the three surviving the acute episode.     

Dobutamine in severe scorpion envenomation: effects on standard hemodynamics, right ventricular performance, and tissue oxygenation.

OBJECTIVES: To document the effects of dobutamine on standard hemodynamics and right ventricular (RV) performance in patients exhibiting pulmonary edema following severe scorpion envenomation, and to characterize the tissue oxygenation profile in patients sustaining scorpion envenomation-related shock. DESIGN: Prospective cohort study. SETTING: An ICU in a university hospital. PATIENTS: Nineteen consecutive patients were admitted to the ICU for severe scorpion envenomation; all 19 patients exhibited hemodynamic pulmonary edema, and 10 patients had peripheral shock. INTERVENTIONS: All patients underwent a hemodynamic study with a Swan-Ganz catheter. In 8 of 19 patients, the thermodilution catheter was equipped with a fast-response thermistor. MEASUREMENTS AND RESULTS: Standard hemodynamic parameters were recorded on admission and following the infusion of dobutamine in all patients at a dosage, from 7 to 20 microg/kg/min, intended to achieve the best hemodynamic and tissue oxygenation compromise. RV ejection fraction (RVEF) and RV volumes were simultaneously recorded in 8 patients, and tissue oxygenation parameters were assessed in the 10 patients with peripheral shock. The clinical signs of tissue hypoperfusion improved, and optimal hemodynamic parameters were achieved at a mean +/- SD dobutamine dosage of 17 +/- 7 microg/kg/min. Dobutamine infusion evoked statistically significant increases in cardiac index, from 2.3 +/- 0.6 to 3.6 +/- 0.7 L/min/m2; stroke volume index, from 18 +/- 5 to 31 +/- 10 mL/m2; and systemic arterial pressure, from 64 +/- 12 to 78 +/- 14 mm Hg. Pulmonary artery occlusion pressure (PAOP) and venous admixture decreased significantly: from 23 +/- 4 to 15 +/- 6 mm Hg and from 29 +/- 7% to 20 +/- 5%, respectively. With respect to RV function, dobutamine infusion significantly increased the RVEF, from 24 +/- 7% to 42 +/- 9%, without significantly changing the RV end-diastolic volume index, reflecting an enhanced RV contractility. In patients with peripheral circulatory failure, the baseline tissue oxygenation profile was consistent with cardiogenic shock, showing increased oxygen extraction as a consequence of a striking depression in oxygen delivery (DO2). After dobutamine infusion, DO2 improved significantly, from 386 +/- 104 to 676 +/- 156 mL/min/m2, with a significant decrease in oxygen extraction, from 34 +/- 8% to 24 +/- 6%. CONCLUSIONS: In severe scorpion envenomation, dobutamine infusion improves impaired heart function. The effects involve both left ventricular and RV dysfunction. Impaired tissue oxygenation is also improved.     

Continuous intravenous midazolam infusion for Centruroides exilicauda scorpion envenomation.

STUDY OBJECTIVE: We sought to describe the effects of continuous intravenous midazolam infusion as therapy for severe bark scorpion (Centruroides exilicauda) envenomation. METHODS: A retrospective chart review from July 1, 1993, through January 1, 1998, identified all patients treated at a university hospital with International Classification of Diseases, Ninth Revision, codes 989.5 (toxic effect of venom) or E905.2 (scorpion sting causing poisoning). By using standardized collection forms, data were extracted from the medical record of every patient who had a grade III or IV envenomation and was treated with a continuous intravenous midazolam infusion. RESULTS: Our search identified 104 patients; 34 had grade III or IV envenomation. Of these, 33 were treated in the ICU with continuous intravenous midazolam infusion. Median patient age was 4 years (range, 1 to 68 years). Midazolam dosage was adjusted to induce a light sleep state to control agitation and involuntary motor activity. The median amount of midazolam resulting in the first recorded decrease in agitation and involuntary motor activity was 0.30 mg/kg (range, 0.03 to 1.76 mg/kg). This first evidence of clinical improvement was recorded as 1.00 hour (median), with a range of 0.00 to 3.75 hours. The initial midazolam infusion rate was 0.10 mg x kg(-1) x h(-1) (median), with a range of 0.01 to 0.31 mg x kg(-1) x h(-1). The maximal midazolam infusion rate was 0.30 mg x kg(-1) x h(-1) (median), with a range of 0.06 to 1.29 mg x kg(-1) x h(-1). The median time until the maximal midazolam infusion rate was 2.5 hours (range, 0.00 to 8.50 hours). The median duration of infusion was 9. 50 hours (range, 4.25 to 20.50 hours). The median length of stay in the ICU was 15.17 hours (range, 6.0 to 28.0 hours), and 85% of patients were discharged directly home. All patients had resolution of abnormal motor activity and agitation during their midazolam infusion. Transient hypoxemia without evidence of end-organ dysfunction was documented in 4 patients during midazolam therapy. CONCLUSION: A continuous intravenous midazolam infusion can be a safe, effective, and readily available treatment option for patients with grade III or IV C exilicauda envenomation.     

Gastrointestinal cytomegalovirus manifestations in AIDS

Cytomegalovirus (CMV) infection is one of the most important intestinal opportunistic infections in AIDS. In severe cases ulcerations and colitis are the commonest manifestations. 184 HIV positive patients with gastrointestinal symptoms were investigated by endoscopy of the gastrointestinal tract. While culture, immunohistochemical staining and histology from biopsies were performed, the results of all three methods were compared. In one third the cases CMV associated lesions could be found by endoscopy. Erosions or ulcerations are the most frequent tissue lesions. In 95% the culture was positive. In addition, immunohistochemical staining in 75% and histology in 61.7% were positive in patients with more serious manifestations. For early diagnosis endoscopy of the gastrointestinal tract and histological, histochemical and microbiological investigations of biopsies are essential.     

Gastrointestinal manifestations of amyloidosis

Amyloidosis is characterized by extracellular deposition of abnormal protein. There are six types: primary, secondary, hemodialysis-related, hereditary, senile, and localized. Primary (AL) amyloidosis is associated with monoclonal light chains in serum and/or urine with 15% of patients having multiple myeloma. Secondary (AA) amyloidosis is associated with inflammatory, infectious, and neoplastic diseases. The presentation is protean, including macroglossia, a dilated and atonic esophagus, gastric polyps or enlarged folds, and luminal narrowing or ulceration of the colon. Amyloid deposition in the gastrointestinal (GI) tract is greatest in the small intestine. The symptoms include diarrhea, steatorrhea, or constipation. Pseudo-obstruction carries a particularly grave prognosis, often not responding to promotility agents. Hepatic involvement is common, but the clinical manifestations are usually mild with hepatomegaly and an elevated alkaline phosphatase level. Biopsies to diagnose amyloidosis can be taken from the fat, kidney, intestine, or bone marrow. The safety of liver biopsies is controversial. With Congo Red stain, amyloid appears red in normal light and apple-green in polarized light. Treatment for AL amyloidosis is chemotherapy and stem cell transplantation; treatment for AA amyloidosis is control of the underlying disease. Amyloidosis should be considered in patients with proteinuria, cardiomyopathy, hepatomegaly (with mildly abnormal liver tests), peripheral and autonomic neuropathy, weight loss, and GI symptoms.     

Gastrointestinal manifestations of leukemia

Gastrointestinal (GI) manifestations of leukemia occur in up to 25% of patients at autopsy, generally during relapse. Its presence varies with the type of leukemia and has been decreasing over time due to improved chemotherapy. Gross leukemic lesions are most common in the stomach, ileum, and proximal colon. Leukemia in the esophagus and stomach includes hemorrhagic lesions from petechiae to ulcers, leukemic infiltrates, pseudomembranous esophagitis, and fungal esophagitis. Lesions in the small and large bowel are usually hemorrhagic or infiltrative. Infiltration of lymphoreticular organs, mainly spleen, liver, and lymph nodes, is more prominent in chronic than acute leukemia. Neutropenic enterocolitis, a necrotizing process involving the cecum, ascending colon, and terminal ileum, is increasing in incidence due to greater intensity of chemotherapy. Distension of bowel leads to mucosal breaches, permitting entry of organisms that grow profusely in the absence of neutrophils. Ischemic necrosis follows, leading to perforation and/or peritonitis. Patients present with fever, abdominal pain, diarrhea, nausea, vomiting, abdominal distension and tenderness. Ultrasound and computed tomography scans show thickening of the bowel wall. Treatment is supportive with surgery for necrosis and perforation. The main GI causes of death in leukemia are hemorrhage, infection, and necrotizing enterocolitis.     

Hemolytic-uremic syndrome secondary to scorpion envenomation (apropos of 2 cases)

HUS was recently described following scorpion sting. We report 2 cases of HUS in the intensive care unit of a university hospital. Two children aged respectively 10 months and 1 year were admitted in the ICU after severe scorpion envenomation (with coma and pulmonary oedema) having required dobutamine and mechanical ventilation. Evolution was marked with acute anaemia without bleeding requiring blood transfusion, acute renal failure, low platelets and signs of haemolysis. Our experience and the previously reported case suggest that scorpion sting could be added to the list of causes of the HUS.     

Black scorpion envenomation: two cases and review of the literature.

Scorpion envenomation is quite common in India, southeast Asia, the U.S. southwest, and Israel (in the Negev and around Jerusalem). Yellow scorpion is considered the most dangerous scorpion that causes cardiac toxicity. Two patients are described, who lived in a nonendemic area of yellow scorpions and were envenomated by the black scorpion. Both suffered temporary cardiac involvement (manifested by electrocardiographic changes) which reverted to a normal pattern within 24 h. These are the first two cases that have been reported (from black scorpion envenomation) and indicate that the toxin of the black scorpion is also cardiotoxic, but much less than the "yellow scorpion" toxin.     

Gastrointestinal manifestations in myotonic muscular dystrophy

Myotonic dystrophy(MD)is characterized by myotonicphenomena and progressive muscular weakness.Involvement of the gastrointestinal tract is frequentand may occur at any level.The clinical manifestationshave previously been attributed to motility disorderscaused by smooth muscle damage,but histologicevidence of alterations has been scarce and conflicting.A neural factor has also been hypothesized.In the upperdigestive tract,dysphagia,heartburn,regurgitation anddyspepsia are the most common complaints,while inthe lower tract,abdominal pain,bloating and changesin bowel habits are often reported.Digestive symptomsmay be the first sign of dystrophic disease and mayprecede the musculo-skeletal features.The impairmentof gastrointestinal function may be sometimes sogradual that the patients adapt to it with little awarenessof symptoms.In such cases routine endoscopic andultrasonographic evaluations are not sufficient andtargeted techniques(electrogastrography,manometry,electromyography,functional ultrasonography,scintigraphy,etc.)are needed.There is a low correlationbetween the degree of skeletal muscle involvement andthe presence and severity of gastrointestinal disturbanceswhereas a positive correlation with the duration of theskeletal muscle disease has been reported.The drugs recommended for treating thegastrointestinal complaints such as prokinetic,anti-dyspeptic drugs and laxatives,are mainly aimed atcorrecting the motility disorders.Gastrointestinal involvement in MD remains acomplex and intriguing condition since many importantproblems are still unsolved.Further studies concentratingon genetic aspects,early diagnostic techniques and thedevelopment of new therapeutic strategies are neededto improve our management of the gastrointestinalmanifestations of MD.     

Gastrointestinal manifestations in Hungarian scleroderma patients

Systemic sclerosis (SSc) is a chronic connective tissue disease characterized by fibrosis and destruction of the microvasculature. Increased deposition of collagen and other extracellular matrix components affects not only the skin but most of the internal organs including lungs, heart, kidneys and the gastrointestinal (GI) tract. Within the GI tract, esophageal involvements are most frequently seen features. However, abnormalities in the small intestine, colon and anorectum may also occur. A retrospective study was performed to investigate the frequency and clinical relevances of GI involvement in patients with SSc. Charts of altogether 246 SSc patients were reviewed. This patient population included 40 males and 206 females, with a mean age of 54.2 years. In general, 176 of 246 patients (71.5%) had GI symptoms. Esophageal involvement including gastro-esophageal reflux disease (GERD), aperistalsis, pseudodiverticuli, etc. was the most common (62.6%). In addition, diseases of the stomach (31.7%), dysfunctions of the colon and anorectum (11.4%), as well as sclerosis of the biliary tract and other pancreato-biliary disorders (9.8%) also occurred. Diarrhea and malabsorption resulted in cachexia and other secondary complications leading to death in two cases. Our results support that GI manifestations are rather common in SSc. Apart from the esophagus, other GI complications in SSc are usually mild, however, early recognition is necessary to improve quality of life.This work was supported by grant No 60/2001 from the Medical Research Council of Hungary (ETT) (Z.S.), and grant No T 048541 from the National Scientific Research Fund (OTKA) (Z.S.).     

Gastrointestinal manifestations of HIV infection

Since the beginning of the AIDS pandemic, gastrointestinal (GI) problems have been among the most common features of the disease. Despite the introduction of highly active antiretroviral therapy (HAART) in 1995 and 1996, most HIV-infected patients continue to have GI complications. The clinician must be able to diagnose and treat the opportunistic gastrointestinal infections and neoplasms that occur in the advanced AIDS patient, as well as the treatment-induced symptoms and non-HIV-related GI disorders that predominate in early HIV disease. This review addresses the GI manifestations of HIV, with particular emphasis on new developments in the era of highly effective therapy.