Acute effects of N-methyl-N'-nitro-N-nitrosoguanidine on canine gastric mucosa

The electrophysiological effects of the chemical gastric carcinogen N-methyl-N'-nitro-N-nitrosoquanidine (MNNG) were determined in an in vivo chambered canine stomach and in an in vitro canine gastric mucosal preparation. In the in vivo stomach, the topical application of 2.5 mg MNNG/ml decreased the transmural electrical potential difference, and the systemic blood pressure was essentially unchanged. In the in vitro preparation, exposure of the mucosal side of the isolated canine gastric mucosa to 0.25 and 2.5 mg MNNG/ml for 1 hour sequentially or exposure of the serosal side to 2.5 mg MNNG/ml for 2 hours inhibited net Na+ and Cl- fluxes. With longer duration, the undirectional fluxes of Na+ and Cl- increased, indicating an increase in permeability. These findings suggested that inhibition of active transport in the gastric mucosa may have an important function in the gastric carcinogenicity of MNNG.     

Outcomes of varicocele ligation done for pain

PURPOSE: Surgical ligation is an option in the management of patients with painful varicocele. Little objective data exist addressing the effectiveness of this treatment. We reviewed records from 58 patients who underwent varicocele ligation at our institution from January 1985 to May 1996 to establish success of surgical ligation of the painful varicocele. MATERIALS AND METHODS: ICD-9 billing codes were used to identify all patients who had undergone varicocele ligation for pain since 1985. We documented patient age, grade and location of varicocele, duration and quality of pain, response to conservative therapy and surgical approach to ligation. Telephone interviews and chart reviews were conducted to determine resolution of pain, complications of the procedure and if the patient would choose surgery again. RESULTS: We obtained followup on 35 of the 58 painful varicocele patients (60%). Average patient age was 25.7 years (range 15 to 65). The varicocele was on the left side in 30 men and bilateral in 5. Of the patients 31 described the pain as a dull throbbing ache, 2 as sharp and 2 as a pulling sensation. Initial conservative therapy failed in all 35 men. Varicocele was grade III in 18 cases, grade II in 16 and grade I in 1. The inguinal or subinguinal approach was used in 24 patients, high ligation in 10 and laparoscopic repair in 1. In 30 patients there was (86%) complete resolution of pain postoperatively and 1 had partial resolution. Only 4 patients (11%) had persistent or worse symptoms. CONCLUSIONS: This retrospective review supports the conclusion that varicocele ligation is an effective treatment for painful varicocele in properly selected patients.     

The local addition of tenoxicam reduces the incidence of low back pain after lumbar epidural anesthesia

BACKGROUND: Postepidural backache is a common postoperative complaint after lumbar epidural anesthesia. Useful interventions to decrease the incidence of postepidural backache would be helpful. METHODS: We performed a prospective, randomized, double-blind study to compare the effect of local addition of tenoxicam on the incidence of postepidural backache after nonobstetric surgery. One thousand unpremedicated ASA physical status I or II patients scheduled for hemorrhoidectomy were assigned randomly to tenoxicam or control groups. Patients in the control group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, for local skin infiltration. Patients in the tenoxicam group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, with tenoxicam (2 mg) 1:2,000 for local skin infiltration. Patients were interviewed at 24, 48, and 72 h postoperatively using a standard visual analog scale for evaluation of postepidural backache. A patient was considered to have postepidural backache when the postoperative visual analog scale score was higher than the preoperative score. RESULTS: The incidence of postepidural backache in patients in the control group for the 3 days were 22.8%, 17.4%, and 9.2%, all of which were significantly more frequent than observed in the patients in the tenoxicam group (6.8%, 4.0%, and 1.2%, P < 0.01). There was a significant association between backache and multiple attempts at epidural needle insertion. CONCLUSION: In summary, the local addition of tenoxicam reduced the incidence and severity of postepidural backache.     

Importance of Doppler analysis of transmitted atrial waveforms prior to placement of central venous access catheters

Cardiac fibrosis is linked to aldosterone-induced hypertension, but the effects on in vivo left ventricular (LV) function are not established. We studied the relations between in vivo LV function and aldosterone/salt cardiac fibrosis. Adult guinea pigs (GPs) were treated for 3 months with an aldosterone infusion and high-salt diet. This treatment induced arterial hypertension (+35%) and moderate LV hypertrophy (LVH; +60%) without right ventricular (RV) hypertrophy. Echo-Doppler LV assessment demonstrated unaltered cardiac output, stroke volume, or LV relaxation. Type I collagen messenger RNA (mRNA) was significantly increased in both ventricles (LV, +48%; RV, +77%) and accompanied by a significant increase in total collagen deposition (LV, from 0.52% in controls to 4.4% in treated GPs; RV, from 0.82 to 5.5% in treated GPs). Plasma norepinephrine levels increased 2.6-fold (p < 0.01) and correlated with the increase in collagen deposition in both ventricles. Collagen content was not correlated with hypertension or LVH. We conclude that aldosterone administration induces cardiac collagen accumulation and a sympathetic stimulation, which might preserve systolic and diastolic function.