Pulse oximetric thresholds for tonsillectomy and adenotomy in children: significance of 1–2% decline in oxyhemoglobin saturation

Objectives:  We aimed to establish optimal overnight pulse oximetric thresholds for determining the indication of tonsillectomy and adenotomy (TA) in children by revising the definition of 'desaturation'.
Methods:  One hundred and thirty four children scheduled for TA (TA group, 5.3 ± 1.4 years old) and 112 otherwise healthy children scheduled for elective minor surgery (control group, 5.4 ± 1.5 years old) were enrolled into this prospective study. Data were recorded and stored every 10 s using Nellcor N-395. Desaturation/resaturation events were defined as x % change ( x  = 1–4) of SpO₂ (oxyhemoglobin saturation by pulse oximetry) in 10 s. The desaturation/resaturation indices were calculated as events per hour of total sleeping time. For each index, a wide range of temporary thresholds was set. The optimal thresholds for TA were the ones that maximized the weighted average for sensitivity, specificity (based on whether the index improved or not after TA), and the percentage of the control children whose indices were below the threshold.
Results:  For all the indices, the optimal thresholds that fulfilled the above condition were determined. Compared with the x  = 3–4% results, the application of x  = 1–2% approximately doubled the TA patients whose preoperative 'positive' indices improved after TA, with the weighted averages of 84.3–92.3% as described above.
Conclusions:  By defining desaturation/resaturation as a 1–2% change in SpO₂ from the preceding value, children with adenotonsillar hypertrophy whose pulse oximetric indices are expected to improve after TA can be detected by pulse oximetry with relatively high sensitivity and specificity.     

A SERIES OF LYSYLDIPEPTIDE DERIVATIVES FOR RACEMIZATION STUDIES IN PEPTIDE SYNTHESIS

The series of diastereomeric peptide derivatives N-benzoyl-d,l -X-N-benzyl-oxycarbonyl-L-lysine methyl ester where X = alanyl, valyl, leucyl, phenylalanyl and isoleucyl are submitted as model systems for studying racemization in peptide synthesis. The diastereomers can be analyzed by quantitation of the separated ester methyl proton peaks of their nuclear magnetic resonance spectra. Data on the tendency to racemize of the different residues are presented. In polar solvents, valyl and isoleucyl residues racemize more readily than the other residues.     

New renin inhibitors containing novel analogues of statine

Solid-phase methodology has been used to synthesize a series of peptides based on the N-terminal sequence of human angiotensinogen in which statine (Sta) or the novel analogues (3S, 4S)-3, 4-diamino- or (3J?, 45)-3, 4-diamino-6-methylheptanoic acid (Ads or R-Ads) and (3S, 4S)-4-amino-3-aminomethyl- or (3R, 4S)-4-amino-3-aminomethyl-6-methylheptanoic acid (Amd or R-Amd) replace either residue 10 or both residues 10–11 at the P₁-P'₁ cleavage site. The synthesis of these novel analogues of statine together with biological results on the inhibition of human and rat renin by peptides derived from them is reported. The absolute stereochemistry of the (3S, 4S) Ads was determined by an X-ray crystallographic analysis of its Nγ-Boc, Nβ-Z, R(+)-1-methyl benzamide derivative. Peptide Boc-His-Pro-Phe-His-Sta-Val-Ile-His-NH₂ (VI) is the best inhibitor of human renin containing Sta at position 10. However, peptides containing Ads and Amd gave better rat renin inhibitors than the corresponding Sta-containing peptides. Peptide Boc-His-Pro-Phe-His-Ads-Val-Ile-His-NH₂ (VII) having Ads at position 10 had an IC₅₀ of 12 nM against rat renin. Although Sta has come to be accepted as an isosteric replacement for a dipeptide unit rather than for a single amino acid residue, in our series of inhibitors Sta is more effective when replacing only the amino acid at position 10 in the natural angiotensinogen sequence. None of the peptides gave any effect in vivo in a hypertensive rat model.     

Analysis of urgent colonoscopy for acute lower intestinal bleeding

Background: Urgent colonoscopy is often performed to diagnose and stop acute lower intestinal bleeding, but its usefulness has yet to be clarified. The aim of this study was to clarify the present role of urgent colonoscopy for this purpose. Methods Urgent colonoscopy was defined as colonoscopy performed within 48 h of the occurrence of hematochezia. All patients investigated by urgent colonoscopy from September 1996 to March 2000 who were hospitalized in Shimane Medical University Hospital or Shimane Prefectural Central Hospital, Japan, were enrolled in this study. The endoscopic data and medical records of all the investigated patients were reviewed retrospectively to clarify the role of urgent colonoscopy for diagnosing and treating patients with hematochezia. Results A total of 152 patients were enrolled and 137 (90.1%) were successfully diagnosed endoscopically. Ischemic colitis was the most frequent disease found (32.9%), followed by postpolypectomy hemorrhage (9.2%), hemorrhoids (8.6%) and rectal ulcer (7.2%). Endoscopic hemostasis was employed to treat postpolypectomy hemorrhage and bleeding rectal ulcers with favorable results. Conclusions Urgent colonoscopy is useful for the diagnosis of hematochezia. Endoscopic hemostasis is frequently required to treat postpolypectomy hemorrhage and bleeding rectal ulcers.     

Masked ureteral duplication with ectopic ureter detected by magnetic resonance imaging

The usefulness of magnetic resonance imaging (MRI) in the detection of a masked duplex kidney system is described. A 9 year old girl was admitted to our hospital for urinary incontinence. She was found to possess an ectopic ureter associated with complete ureteral duplication. She had been evaluated for incontinence at several hospitals, but neither ultrasound sonography nor intravenous pyelography detected any abnormalities. Only cystoscopic examination and MRI detected the anomalies. Partial nephroureterectomy resolved the patient's incontinence. MRI is useful for the detection of ureteral duplication and should be used on cases in which this condition is suspected, prior to performing invasive procedures.     

Characteristics of patients with staghorn calculi in our experience

PURPOSE: To elucidate the factors contributing to staghorn stone formation in patients. MATERIALS AND METHODS: The records of 82 patients (44 men and 38 women) with complete staghorn calculi were reviewed retrospectively for clinical presentation, metabolic disturbances and anatomical abnormalities. RESULTS: There were 79 unilateral and three bilateral cases. The patient performance of the activities of daily life was assessed with the modified Rankin scale (MRS) and it was found that 69 patients were functionally independent (84.1%, MRS 0-1) and 10 patients had a severe disability (12.2%, MRS 4-5). Seven patients had chronic indwelling catheters (8.5%). A positive urine culture was found in 24.4% of patients. Analysis of stone composition revealed magnesium ammonium phosphate and mixed calcium oxalate-phosphate were the most frequently identified types of stone (32.1% and 22.2%, respectively). Urinary pH was low in patients with uric acid stones (mean 5.4). Hyperuricemia, cystinuria and hypercalciuria were found in 14.6%, 2.4% and 37.8%, respectively. Hypercalciuria was found more frequently in calcium-stone cases. Eleven patients (13.4%) showed structural abnormalities of the kidney. CONCLUSIONS: Our data show that the patients with severe disability, urinary tract infection and hypercalciuria could be recognized more frequently in staghorn calculi compared with common urolithiasis. However, in Western countries, the frequency of both urinary tract infection and struvite stones is much higher than in our data. Other Japanese authors have also reported the low frequency of struvite stones in staghorn calculi, suggesting that various factors other than urinary tract infection possibly contribute to the formation of staghorn calculi in Japan.     

Invasive micropapillary carcinoma of the urinary bladder: An immunohistochemical study of neoplastic and stromal cells

A 66-year-old man complained of hematuria. A cystoscopy revealed a non-papillary tumor and radical cystectomy was performed. Macroscopically, an ulcerative lesion was observed. Microscopically, the neoplasm showed a mixture of urothelial carcinoma, squamous cell carcinoma and micropapillary carcinoma. Immunohistochemically, micropapillary carcinoma cells were positive for cytokeratins 7 and 20, carcinoembryonic antigen and CA125. Additionally, myofibroblasts were distributed in a chicken-wire pattern in the stroma of micropapillary carcinoma. Subsequently, the patient died of carcinoma 1 year after the onset of symptoms. Our results support the previous hypothesis that bladder micropapillary carcinoma runs an aggressive clinical course and suggest that micropapillary carcinoma may show the glandular differentiation of urothelial carcinoma and show the stromal reaction by myofibroblasts resembling that of carcinoma in other anatomic sites.     

Recurrence pattern for superficial bladder cancer

AIM: Patients with superficial bladder tumors sometimes have long recurrence-free intervals. We evaluated whether patients with long recurrence-free periods had subsequent recurrences. We also clarified how these patients should be followed. MATERIALS AND METHODS: We enrolled 244 patients with superficial bladder cancer (62 pTa and 182 pT1) treated by transurethral resection of bladder tumor (TURBT) and adjuvant chemotherapy with pirarubicin. Median follow up was 75.5 months. Patients were stratified by the length of their recurrence-free interval. RESULTS: Recurrences occurred in 124 patients (50.8%). Of 185 patients who did not have a recurrence for the first 3 years, subsequent recurrences occurred in 65 patients; in more than half the first recurrence developed after 5 years or more. Ta tumors had a low recurrence rate (14.5%) with the first recurrence often developing after a long recurrence-free period. Of 40 patients who remained recurrence-free for 3 years or more after at least one recurrence occurred, 16 patients (40%) had subsequent recurrences. Furthermore, most of these patients who remained free of recurrence for more than 5 years eventually had a recurrence. The overall progression rate was 15.6%, and this did not relate to the length of the recurrence-free interval. CONCLUSION: When patients did not have a recurrence for the first 3 years, tumors subsequently often recurred, even in pTa tumors. In patients with at least once recurrence, subsequent recurrences appear to occur irrespective of the length of the recurrence-free period. Thus, we recommend that all patients with superficial bladder tumors be followed for as long as possible.     

Correlation between serum pepsinogen concentration and gastric acidity measured by 24 h pH monitoring

Abstract The relationship between the intragastric pH measured by 24 h pH monitoring system and the serum pepsinogen I/II ratio was studied in 68 cases. When pepsinogen I/II ratio was compared with pH 3.0 holding time (the percentage time during which the gastric pH is above 3.0), there was a negative correlation between these two parameters (correlation coefficient r = -0.62, P < 0.001). Furthermore, there was also a strong negative correlation between the early morning (from 03.00 to 06.00 h) gastric pH and pepsinogen I/II ratio ( r = -0.76, P < 0.001). Accordingly, by simply measuring serum pepsinogen I and II, it may be possible to infer gastric acidity and to obtain the information concerning the early morning intragastric pH.     

A case of four coronary artery fistulae originating from three vessels associated with aneurysm

A case of an aneurysm associated with four coronary artery fistulaeoriginating from three vessels is reported. The patient, a 52-year-oldwoman, had chest heaviness and palpitations. Coronary arteriographyreveaed the four fistulae originating from three coronary vesselswith an aneurysm draining into the left ventricle and the mainpulmonary artery.The patient's symptoms were relieved afterfistulectomy and the aneurysmectomy, suggesting that a coronarysteal phenomenon through the fistulae was the cause of her symptoms.This case is of interest because of its rarity, since this isthe first case report of an aneurysm associated with four coronaryartery fistulae from three vessels.