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PubMed1998

Effects of effusion in the middle ear and perforation of the tympanic membrane on otoacoustic emissions in guinea pigs.

The influence of fluid in the middle ear and of perforation and closure of the tympanic membrane (TM) on otoacoustic emissions (OAEs) was evaluated in guinea pigs. Click-evoked otoacoustic emissions (CEOAEs) and distortion product otoacoustic emissions (DPOAEs) were measured after the auditory bulla was opened. Neither OAE level changed significantly when fluid filled only half the space in the bulla, but both OAE levels disappeared when fluid completely filled the bulla. These changes were reversible. Thus, the presence of fluid in the bulla influenced CEOAE and DPOAE levels only when its volume filled more than half the space of the bulla. Changes in both CEOAE and DPOAE levels were affected by the size of the perforation of the tympanic membrane. For the smallest perforation, the reduction in both CEOAE and DPOAE levels was restricted to the lower frequencies. However, as the size of the perforation increased, a decrease in high-frequency function occurred. Thus, the results indicate that the magnitude of both OAEs was proportional to the size of the perforation. Both OAE levels improved after the perforation was closed. Because CEOAEs were more sensitive than DPOAEs to perforation and closure of the TM, DPOAEs may be better suited for OAE measurement in ears with perforated TMs.

Acoustic Stimulation↗
PubMed2003

Treatment and outcomes of oesophageal perforation in a tertiary referral centre.

OBJECTIVE: The diagnosis and management of oesophageal perforation continues to challenge clinicians. We present our experience of perforated oesophagus in a Tertiary Referral Centre for Thoracic and Oesophageal Surgery. METHODS: Between 1985 and 2000, 75 patients (40 male) with oesophageal perforation were treated in out unit; age range 24-89, median 63. Retrospective review of these cases has been performed. RESULTS: There were 12 deaths (16%). With increases in time from perforation to diagnosis, there was a stepwise increase in the mortality rate. Immediate diagnosis 5%; early diagnosis (1-24h) 14%; late diagnosis (>24h) 44% (P>or=0.002). Site of perforation, aetiology, and treatment strategy had no influence on mortality. The only independent predictor of mortality identified was time to diagnosis from perforation (beta 0.429, P=0.001). Time to definitive management in those undergoing an operative procedure had no influence on outcome with multivariate analysis. CONCLUSIONS: Prompt recognition of the diagnosis of oesophageal perforation and rapid institution of supportive measures, followed by an appropriate, patient specific treatment option optimises the chance of a successful outcome. The wide range of presentation of oesophageal perforation necessitates individualisation of treatment.

Adult↗
PubMedDate not supplied

Nonsurgical management of gastric or duodenal perforation from a Wills-Oglesby-type gastrostomy tube.

PURPOSE: To describe the clinical and radiologic appearance of gastrointestinal perforation related to a Wills-Oglesby-type gastrostomy tube, as well as techniques for nonsurgical management. MATERIALS AND METHODS: Five patients with a previously placed 14-F modified Wills-Oglesby-type gastrostomy catheter experienced viscus perforation by the distal limb of the catheter during a 30-month period. RESULTS: The average interval between tube placement and perforation event was 4.3 months. Three patients had migration of the gastrostomy tube into the duodenum and subsequent duodenal perforation. One patient had posterior perforation of the stomach, and one patient developed a gastrocolic fistula. Generalized peritonitis was not present in any patient. All patients were treated successfully without surgery, and tube feedings were re-established in 4-14 days. CONCLUSIONS: Gastrostomy tube-related perforation is an uncommon, delayed complication of percutaneous gastrostomy with the modified Wills-Oglesby-type catheter. Nonsurgical management is feasible in select instances. Because of these gastrointestinal perforations, the gastrostomy tube has been modified (eliminating the distal tip), and no gastrostomy-associated gastrointestinal perforation has been experienced since.

Adolescent↗
PubMed2002

Risk of uterine perforation during hysteroscopic surgery.

STUDY OBJECTIVE: To evaluate the rate of uterine perforation during different operative hysteroscopy procedures. DESIGN: Observational study (Canadian Task Force classification II-2). SETTING: Department of Obstetrics and Gynecology, La Conception Hospital, Marseille, France. PATIENTS: One thousand nine hundred fifty-two women. INTERVENTION: Of 2116 operative hysteroscopies performed, there were 623 endometrectomies, 782 myoma resections, 422 polyp resections, 199 adhesiolyses, and 90 uterine septa sections. MEASUREMENTS AND MAIN RESULTS: Risk of perforation was evaluated according to hysteroscopic procedure. Severity of complications were also noted. In case of perforation, a management protocol was applied to prevent metabolic disorders and pelvic infections. Thirty-four perforations (1.61%) were reported. In 33 cases (97%) it was realized during the procedure and no complications occurred during follow-up. One perforation with hemorrhage was misdiagnosed during the intervention and required laparotomy. Perforation risk was higher during hysteroscopic adhesiolysis than during other procedures [endometrial ablation RR 9.39 (3.46-25.52), p <0.0001; uterine septa section RR 6.78 (0.91-50.6), p = 0.026; polyp RR 8.52 (2.60-30.80), p <0.0001 or myoma resection RR 7 (2.83-17.62), p <0.0001]. Perforation risk was comparable during endometrial ablation, uterine septa section, and polyp or myoma resection (p = 0.93). CONCLUSION: Perforation risk is higher during synechiolysis than in other indications for hysteroscopy. Severe complications are rare but may be avoided if precautions are taken.

Endometrial Neoplasms↗
PubMed2004

Peritoneal needle suction for intestinal perforation in the preterm neonate.

UNLABELLED: A few years ago, most intestinal perforations in the premature newborn appeared within the clinical context of necrotising enterocolitis (NEC). Since then, we have observed an increase in the number of isolated perforations appearing outside typical NEC. The fact that the perforations are more often isolated, and the healing capabilities of the premature intestine, led us to propose peritoneal needle suction (PNS) alone as first treatment for intestinal perforations in the premature neonate. MATERIALS AND METHOD: The charts of 6 consecutive premature infants presenting with intestinal perforations treated initially by PNS alone were reviewed. RESULTS: The patients' median birth weight was 1030 g, with a median gestational age of 27 weeks. In 5 out of 6 infants (83 %), PNS achieved complete exsufflation without recurrence of the pneumoperitoneum and complete intestinal healing, allowing complete enteral feeding 30 to 71 days after perforation. One infant with recurrent pneumoperitoneum after 3 PNS and peritoneal drainage was operated. All infants survived. CONCLUSION: We believe that for early perforations of the premature neonate, the poor diffusion of the infection and the frequent capacity of the perforation to close and subsequently heal without scars, favour a minimally invasive management using PNS.

Humans↗
PubMed2006

Successful nonsurgical management of perforation complicating endoscopic submucosal dissection of gastrointestinal epithelial neoplasms.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) is a novel technique used for the treatment of gastrointestinal neoplasia. One of its major limitations, however, is the complication of perforation. PATIENTS AND METHODS: We included in our study all the cases of perforation that occurred during ESD procedures for gastrointestinal epithelial neoplasia between February 2000 and February 2005. Clinical outcomes after perforation were investigated. RESULTS: Perforation was experienced at 27 lesions in 27 patients (four in the esophagus, fourteen in the stomach, seven in the colon, and two in the rectum). Fibrosis under the lesions was confirmed histologically in seven patients (26 %). Immediate closure using endoclips was performed in all patients except for three asymptomatic patients in whom a stomach perforation was first noticed when free air was noticed on a radiograph the morning after the ESD procedure. Air accumulation was detected radiographically in 21 patients (78 %). The mean duration of antibiotic treatment was 6.7 days and the patients were fasted for a mean period of 5.3 days. The mean maximum body temperature was 37.3 degrees C, the mean white blood cell count was 9733/mm3, and the mean C-reactive protein level was 5.0 mg/dl. All the patients were discharged well from the ward after a mean time of 12.1 days after ESD, and no recurrence caused by tumor spread from the perforation occurred in any patient after a median follow-up period of 36 months (range 9 - 52 months). CONCLUSION: Successful nonsurgical management after ESD complicated by perforation is a highly feasible option if intensive conservative treatments are used following immediate endoscopic closure of the perforation.

Aged↗
PubMed1997

Colonic perforation due to colonoscopy: a retrospective study of 48 cases.

BACKGROUND AND STUDY AIMS: The aim of this retrospective study was to analyze data on the treatment of 48 cases of colonic perforation, with a view to defining the criteria for choosing between medical and surgical treatment. PATIENTS AND METHODS: A questionnaire requesting information about complications of colonoscopy and their treatment was sent out to four hospital gastroenterological and surgical units. RESULTS: From January 1979 to December 1993, we reviewed the records of 48 cases of colonic perforation following colonoscopy (24 perforations occurred after diagnostic colonoscopy and 24 after therapeutic colonoscopy). Diagnosis of perforation was delayed in 42% of the patients, with a mean delay of two days (range 0.5-7 days). The treatment was surgical in 35 cases, including eight in which previous medical treatment had been unsuccessful. The perforation was in the sigmoid colon in 74% of the surgical population. Operations were carried out using two procedures, including colostomy, in the case of 20 patients (57%). Colostomy closure was performed in 12 patients (60%) with no mortalities. Surgical mortality occurred in five patients (14%), in four cases due to preexisting medical diseases. Medical treatment was attempted in 21 cases, and was successful in 13, mainly in cases in which perforation had occurred after therapeutic colonoscopy (12 patients). CONCLUSION: The choice of the right type of treatment for colonoscopic perforation seems to depend on the size of the lesion. Surgical treatment is appropriate when the perforation has occurred during diagnostic colonoscopy, since the lesion in this case is usually a large colonic laceration, whereas nonsurgical treatment seems to be justified after polypectomy, as long as there is rapid clinical improvement.

Adolescent↗
PubMed2004

Spontaneous healing of various tympanic membrane perforations in the rat.

OBJECTIVES: To investigate the spontaneous healing process of various types of perforation and the location of the epithelial generation center in the tympanic membrane of rats. MATERIAL AND METHODS: Various types of perforation were made in the ears of 50 rats and the healing process was observed using light and electron microscopy. RESULTS: Epithelia hyperplasia could not be seen at the edge of the perforations, but occurred in the annulus and handle of malleus regions during the early stage of healing. There was no correlation between the healing time and the size of the perforations. When one ear was perforated, no changes were observed in the intact ear on the other side. The epithelium did not migrate into the tympanic cavity in the posterior marginal perforations. All the perforations healed, although the manubria of the malleus were damaged. CONCLUSIONS: The perforations healed by means of epithelial migration. The epithelial generation center was located near the annulus and the handle of the malleus, and therefore protection of these two regions is very important in middle ear surgery.

Animals↗
PubMed1998

Conventional plain-film radiology, ultrasonography and CT in jejuno-ileal perforation.

PURPOSE: To evaluate conventional radiography, US and CT in identifying jejuno-ileal perforation. MATERIAL AND METHODS: We retrospectively reviewed the findings of conventional radiography, US and CT in 13 consecutive patients with surgically proven jejuno-ileal perforation. RESULTS: The site of perforation was the ileum in 10 cases and the jejunum in 3 cases. Free gas was identified in 6 cases (46%) while indirect findings of perforation were found in 7 (54%). The jejunal perforations were diagnosed by indirect findings in all 3 cases. The ileal perforations were diagnosed by direct findings in 6 cases and indirect findings in 4 cases. CONCLUSION: Conventional radiology did not detect free gas in 7 (54%) of the 13 patients examined. In the absence of free gas, radiology showed indirect signs in all 7 patients, the most common being intraperitoneal free fluid in 5 (71%) of them. Jejunal perforations were more rare than ileal perforations and more difficult to identify by radiology. US was not useful for detecting free gas but it was useful for identifying intraperitoneal free fluid and intestinal paresis. Abdominal CT was useful when performed 6 h after the symptoms began.

Adolescent↗
PubMed1989

All perforated ulcers are not alike.

To determine if ulcer location and other clinical factors affect the hospital course and early outcome of patients with perforated peptic ulcers in the decade since the introduction of H2 receptor antagonists, the records of 80 patients with perforated peptic ulcers were analyzed. Demographic factors, clinical features, and the outcome of patients with duodenal ulcer perforation were similar to patients with prepyloric ulcer perforation. In contrast, patients with gastric ulcer perforation had differing characteristics from the group with perforated pyloroduodenal ulcers. Overall, NSAID use preceded perforation in one half of the patients; severe coexisting medical illness and a short interval of symptoms before perforation were seen in more than one half of patients. Gastric ulcer location, hemodynamic instability, greater degree of peritoneal contamination, and larger ulcer size were factors associated with increased rates of mortality. Overall mortality rate was 12.5% and rate of morbidity was 33%. Oversewing with or without omental patch was the operation most commonly employed by a diverse group of surgeons.

Adult↗
PubMed1997

Role of Helicobacter pylori infection in perforation of peptic ulcer: an age- and gender-matched case-control study.

Evidence showed a marked decrease in recurrence rate of peptic ulcer after eradication of Helicobacter pylori infection. However, whether H. pylori infection is etiologically related to perforation of peptic ulcer remains to be clarified. We therefore conducted an age- and gender-matched case-control study between perforated and nonsurgical peptic ulcers in H. pylori infection and examined differences in the cytotoxin genes cagA and vacA. Serum H. pylori IgG antibody (ELISA) was positive in 20/21 (95%) of perforated vs. 37/40 (93%) of nonsurgical duodenal ulcers and in 5/5 (100%) of perforated vs. 24/28 (86%) of nonsurgical gastric ulcer patients. Positivity of H. pylori DNA in gastric juice, which was amplified by PCR and identified by Southern blot hybridization, was 17/23 (74%) of perforated vs. 32/45 (71%) in the nonsurgical duodenal ulcer group. Positivity of the cytotoxin genes cagA and vacA in H. pylori DNA-positive gastric juice was as follows: perforated vs. nonsurgical duodenal ulcer, cagA 11/ 13 (85%) vs. 24/27 (89%); vacA1: 9/13 (69%) vs. 22/27 (82%); vacA2 8/13 (62%) vs. 21/27 (78%). There were no significant differences between the perforated and nonsurgical peptic ulcer groups for these H. pylori serum and gene markers. It is assumed that H. pylori infection is not etiologically related to perforation of peptic ulcer.

Antigens, Bacterial↗
PubMed1998

Cell count ratio: new criterion of diagnostic peritoneal lavage for detection of hollow organ perforation.

OBJECTIVES: Diagnostic peritoneal lavage (DPL) had been widely used in evaluating patients with suspected intraperitoneal injuries due to its high sensitivity. If the positive criteria are strictly followed, however, the incidence of nontherapeutic laparotomies will be unacceptably high. This realization has become more important recently with the popularization of nonoperative treatment for blunt solid organ injuries. For these patients, the early diagnosis of an associated hollow organ perforation is mandatory. METHODS: Three hundred and twenty patients undergoing DPL over an 18-month period were retrospectively reviewed to evaluate the usefulness of "cell count ratio" in diagnosing hollow organ perforation. The cell count ratio was defined as the ratio between white blood cell count and red blood cell count in the lavage fluid divided by the ratio of the same parameters in the peripheral blood. RESULTS: Two hundred twelve patients were diagnosed as having a positive DPL according to the classic criteria. Forty-four patients (21%) had a cell count ratio of greater than or equal to 1. The diagnosis at laparotomy was small bowel perforation in 31 patients, colon perforation in eight patients, diaphragmatic hernia in one patient, pancreatic transection in two patients, and liver laceration in two patients. None of the patients with a cell count ratio of less than I sustained hollow organ perforation. The average interval from injury to DPL was 5 hours, with the shortest being 1.5 hours. CONCLUSION: A cell count ratio of greater than or equal to 1 predicted hollow organ perforation with a specificity of 97% and a sensitivity of 100%. The selective use of the cell count ratio has improved the probability of early diagnosis of bowel perforation without increasing the cost of care. Nonoperative management can be applied more confidently to those patients sustaining a blunt solid viscus injury of the abdomen if the cell count ratio is low. We conclude that the cell count ratio of DPL effluent is a very sensitive and specific indicator of hollow organ perforation. In the treatment of blunt abdominal injuries, if the cell count ratio is positive, nonoperative treatment should be abandoned and a laparotomy undertaken.

Abdominal Injuries↗
PubMed2004

Impact of mastoidectomy on simple tympanic membrane perforation repair.

OBJECTIVES/HYPOTHESIS: Mastoidectomy has long been identified as an effective method of treatment for chronic ear infection. The effect of mastoidectomy on patients without evidence of active infectious disease remains highly debated and unproven. The objective in the study was to examine the impact of mastoidectomy on the repair of uncomplicated tympanic membrane perforations. STUDY DESIGN: Retrospective study of patients at tertiary referral center. METHODS: Four hundred eighty-four patients who underwent surgical repair of simple tympanic membrane perforations were identified and reviewed in a retrospective manner. Simple tympanic membrane perforations were defined as tympanic membrane perforations of any size and location without any of the following confounding variables: 1). active infection (active otorrhea, abnormal middle ear mucosa, or granulations tissue); 2). ossicular abnormalities (ossicular fixation, ossicular discontinuity, ossicular malformation, or ossicular absence); 3). cholesteatoma; or 4). prior attempt at tympanic membrane repair (prior tympanoplasty or mastoidectomy). Surgical outcome and clinical course were assessed to compare results of tympanic membrane perforation repair with and without canal wall up mastoidectomy. RESULTS: Tympanic membrane repair was equally effective in both groups at 91%. Hearing results were comparable. Development of persistent ipsilateral otological disease requiring a subsequent ipsilateral procedure was approximately twice as common in the tympanoplasty group. In the tympanoplasty group, 14.1% of patients underwent subsequent ipsilateral otological procedures, and 6.1% of patients in the tympanoplasty with mastoidectomy intact canal wall group underwent subsequent ipsilateral procedures (P <.05). The most common subsequent ipsilateral procedures were tympanoplasty, tympanostomy tube placement, tympanoplasty with mastoidectomy canal wall up, and tympanoplasty with mastoidectomy canal wall down, in that order. After including untreated tympanic membrane perforations as subsequent procedures, the adjusted rate of subsequent procedures was 15.5% in the tympanoplasty group and 12.2% in the tympanoplasty with mastoidectomy group (P >.05). CONCLUSION: Mastoidectomy was not necessary for successful repair of simple tympanic membrane perforations. However, mastoidectomy impacted the clinical course in patients by reducing the number of patients requiring future procedures and by decreasing disease progression. This suggests that even in the absence of active evidence of infection, mastoidectomy improved the underlying disease process. Combining mastoidectomy with tympanoplasty during repair of simple perforations in patients with no active evidence of infection remains an appropriate option and may be valuable in reducing the need for future surgery.

Adolescent↗
PubMed2000

Factors associated with intestinal perforation in children's non-typhi Salmonella toxic megacolon.

BACKGROUND: To evaluate the risk factors for intestinal perforation in children with toxic megacolon caused by non-typhi Salmonella infection. METHODS: During an 11-year period we reviewed the records of children treated for non-typhi Salmonella infection. All of the subjects had positive stool culture for non-typhi Salmonella and were treated with intravenous ceftriaxone during hospitalization. Clinical data reviewed included demographic features, clinical manifestations, laboratory findings, radiologic findings, microbiology, therapeutic effect of hydration and rectal tube placement and the operative findings. Patients with toxic megacolon were defined as those having toxic appearance, diarrhea, high fever (>39 degrees C) and marked colon dilatation with maximal diameter > 1.5 times the width of the vertebra body of the first lumbar spine (L1-VB). To define the risk factors for patients with toxic megacolon complicated by intestinal perforation, patients were divided into two groups for analysis: P group, those complicated with intestinal perforation; and NP group, those without intestinal perforation. Differences in age, sex, severity of diarrhea, duration of fever, hemogram and its differential, culture, stool analysis, serum C-reactive protein (CRP), electrolytes, maximal colon diameter, medical therapy and timing of rectal tube insertion between the two groups were analyzed. Statistical analyses were conducted with chi square tests and multiple logistic regression. RESULTS: A total of 75 patients (P group, 27 patients; NP group, 48 patients) ages 4 months to 6 years were evaluated. With chi square analysis 7 variables were found to be significantly associated with intestinal perforation: age >1 year; fever >5 days; ratio of immature to total neutrophils >20%; serum CRP >200 mg/l; colon diameter >2.5 times the width of L1-VB; inadequate early hydration; and delay in rectal tube insertion. With multivariate analysis age >1 year, serum CRP >200 mg/l and colon diameter >2.5 times of width of L1-VB, inadequate early hydration and delay in rectal tube insertion were the most significant factors associated with intestinal perforation. CONCLUSION: Identification of patients with toxic megacolon associated with non-typhi Salmonella infection at risk for further intestinal perforation is possible. Early effective fluid resuscitation and rectal tube insertion may be helpful to prevent the occurrence of intestinal perforation.

Child↗
PubMed2006

Healing of subacute tympanic membrane perforations in chinchillas treated with epidermal growth factor and pentoxifylline.

HYPOTHESIS: The aims of the present study were to determine the effect of epidermal growth factor (EGF) and pentoxifylline on subacute tympanic membrane (TM) perforations and to quantify the healing rate of such perforations treated with these drugs alone or in combination. BACKGROUND: It is known that EGF modulates in vitro and in vivo proliferation of epithelial and endothelial cells. Pentoxifylline is a methylxanthine that has been used to treat experimental skin flaps and venous leg ulcers. Data in the literature regarding this subject are contradictory, and quantitative data regarding the effects of EGF and pentoxifylline on TM perforation healing are scarce. METHODS: We studied 50 chinchillas submitted to TM perforation. On postoperative Day 30, eight were selected for histologic analysis. Of the remaining 42, those presenting little or no healing were distributed into four groups: control, EGF, pentoxifylline, and EGF combined with pentoxifylline. RESULTS: Histologic analysis showed that the observation period adopted was sufficient to consider the TM perforations subacute. We found significant differences between the study groups and the control group in the healing rate of subacute TM perforations during a 30-day period (analysis of variance; p < 0.001), which was 30.3% for the EGF group, 3.6% for the pentoxifylline group, 16.5% for the EGF-pentoxifylline group, and 8.7% for the control group. CONCLUSIONS: The use of EGF promoted healing of subacute TM perforations in chinchillas, and the use of pentoxifylline did not. The combination of the two had no synergistic effect on the healing of these perforations.

Analysis of Variance↗
PubMed2005

Esophageal perforation in adults: aggressive, conservative treatment lowers morbidity and mortality.

OBJECTIVE: To evaluate the outcome of aggressive conservative therapy in patients with esophageal perforation. SUMMARY BACKGROUND DATA: The treatment of esophageal perforation remains controversial with a bias toward early primary repair, resection, and/or proximal diversion. This review evaluates an alternate approach with a bias toward aggressive drainage of fluid collections and frequent CT and gastographin UGI examinations to evaluate progress. METHODS: From 1992 to 2004, 47 patients with esophageal perforation (10 proximal, 37 thoracic) were treated (18 patients early [<24 hours], 29 late). There were 31 male and 16 females (ages 18-90 years). The etiology was iatrogenic (25), spontaneous (14), trauma (3), dissecting thoracic aneurysm (3), and 1 each following a Stretta procedure and Blakemore tube placement. RESULTS: Six of 10 cervical perforations underwent surgery (3 primary repair, 3 abscess drainage). Nine of 10 perforations healed at discharge. In 37 thoracic perforations, 2 underwent primary repair (1 iatrogenic, 1 spontaneous) and 4 underwent limited thoracotomy. Thirty-4 patients (4 cervical, 28 thoracic) underwent nonoperative treatment. Thirteen of the 14 patients with spontaneous perforation (thoracic) underwent initial nonoperative care. Overall mortality was 4.2% (2 of 47 patients). These deaths represent 2 of 37 thoracic perforations (5.4%). There were no deaths in the 34 patients treated nonoperatively. Esophageal healing occurred in 43 of 45 surviving patients (96%). Subsequent operations included colon interposition in 2, esophagectomy for malignancy in 3, and esophagectomy for benign stricture in 2. CONCLUSIONS: Aggressive treatment of sepsis and control of esophageal leaks leak lowers mortality and morbidity, allow esophageal healing, and avoid major surgery in most patients.

Adolescent↗
PubMed2005

GABA synapses and the rapid loss of inhibition to dentate gyrus granule cells after brief perforant-path stimulation.

PURPOSE: To study the pharmacologic and synaptic basis for the early loss of paired-pulse inhibition that occurs in the perforant-path stimulation model of status epilepticus. METHODS: Hippocampal slices were prepared from male Wistar rats. Test paired pulses (20- to 50-ms interstimulus interval) of the perforant path were used before and after an abbreviated period of perforant-path stimulation (1-5 min; 2-Hz continuous with 20 Hz of 10 s/min pulses) while either recording field potentials from the dentate gyrus granule cell layer or directly measuring whole-cell patch-clamp currents from granule cells. Paired-pulse field recordings also were obtained during perfusion of the gamma-aminobutyric acid (GABA)(A) antagonist bicuculline. RESULTS: Prolonged loss of paired-pulse inhibition occurs after brief (< 5 min) perforant-path stimulation in vitro (similar to results in vivo) with the paired-pulse population spike amplitude ratio (P2/P1) increasing from a baseline of 0.53 +/- 0.29 to 1.17 +/- 0.09 after perforant-path stimulation (p < 0.05). After perfusion with the GABA(A) antagonist, bicuculline, the P2/P1 ratio also increased from a baseline of 0.52 +/- 0.16 to 1.15 +/- 0.26 (p < 0.05). After 1-2 min of perforant-path stimulation, a 22 +/- 6% (p < 0.05) decrease occurred in the P2/P1 amplitude ratio of paired-pulse evoked inhibitory postsynaptic currents. CONCLUSIONS: Similar to in vivo, loss of paired-pulse inhibition occurs with brief perforant-path stimulation in vitro. GABA(A) antagonism causes a similar loss of paired-pulse inhibition, and the effects of perforant-path stimulation on postsynaptic inhibitory currents also are consistent with the involvement of GABA(A) synaptic receptors. The findings suggest that loss of inhibition at GABA synapses may be an important early event in the initiation of status epilepticus.

Animals↗
PubMed1997

Smoking and ulcer perforation.

BACKGROUND: The use of ulcerogenic drugs is the only well documented risk factor for peptic ulcer perforation, but accounts for only a quarter of the events. Smoking is a well known risk factor for uncomplicated ulcer disease, and patients with ulcer bleeding have increased death rates from smoking related disorders. AIM: To assess the role of smoking in ulcer perforation. SUBJECTS: A total of 168 consecutive patients with gastroduodenal ulcer perforation and 4469 control subjects from a population based health survey. METHODS: The association between ulcer perforation and smoking habits was analysed by logistic regression while adjusting for age and sex. RESULTS: Current smoking increased the risk for ulcer perforation 10-fold in the age group 15-74 years (OR 9.7, 95% CI 5.9 to 15.8) and there was a highly significant dose-response relationship (p < 0.001). The results were similar in men (OR 9.3, 95% CI 4.9 to 17) and women (OR 11.6, 95% CI 5.3 to 25), and for gastric (OR 10.5, 95% CI 4.5 to 25) and duodenal (OR 8.6, 95% CI 4.9 to 15.4) ulcer perforation. No increase in risk was found in previous smokers (OR 0.8, 95% CI 0.2 to 2.2). CONCLUSION: Our findings suggest that smoking is a causal factor for ulcer perforation and accounts for a major part of ulcer perforations in the population aged less than 75 years.

Adolescent↗