The zero-stress state of the esophagus is the state in which the esophagus is stress-free. It is in close correlation with physiology and pathology of the esophagus. The purpose of the review is to describe briefly the basic theory of zero-stress state and its physiological and pathologic implications in the esophagus.
Esophagus ; physiology ; physiopathology ; Humans ; Stress, Physiological

Adult ; Anus/*physiopathology ; Constipation/etiology ; Esophagus/physiopathology ; Female ; Human ; Manometry ; Middle Age ; Rectum/*physiopathology ; Scleroderma, Systemic/*physiopathology

To determine the relationship between Barrett's esophagus (BE) and features of gastroesophageal acid reflux, 24 h esophageal pH monitoring was performed in 90 patients. The patients were divided into 3 groups: 31 subjects with BE, 21 with mild esophagitis and 38 with severe esophagitis. The following parameters were evaluated: the percentage time of pH < 4; the number of reflux episodes over 5 min; the duration of longest episodes and DeMeester score over total period and the auterior three parameters in erect and supine position. All these parameters in BE were significantly different from those with mild esophagitis (P < 0.01) and not significantly different from those with severe esophagitis (P > 0.05). During supine position all the above parameters in BE were significantly different from those with reflux esophagitis (P < 0.05). It is concluded that the quantity of acid reflux is not an important factor in development of BE in gastroesophageal reflux (GER), and the acid reflux in supine position might be important in development of BE in GER.
Barrett Esophagus/etiology ; Barrett Esophagus/*physiopathology ; Esophagitis, Peptic/etiology ; Gastroesophageal Reflux/*complications ; Hydrogen-Ion Concentration ; Supine Position

OBJECTIVETo discuss the occurrence correlation between obstructive sleep apnea hypopnea syndrome (OSAHS) and gastroesophageal reflux disease (GERD).

METHODSForty-three patients suspected of laryngopharyngeal reflux disease underwent combined multichannel intraluminal impedance and esophageal manometry (MII-EM), twenty-four-hour esophageal and pharyngeal pH and impedance monitoring and PSG. Subjects were grouped according to the detections. The difference of the measurement between groups were Compared. The possible relationship between the two diseases was analyzed.

RESULTSFourteen of all the subjects can be diagnosed to have GERD (32.6%). Twenty-six can be diagnosed to have OSAHS (60.5%). There were 10 patients had OSAHS and GERD simultaneously, which took over 38.5% of the OSAHS group, and 71.4% of the GERD group. BMI (P = 0.000) and lower esophageal sphincter (LES) residual pressure (P = 0.021) were significantly different among the four groups OSAHS, GERD, OSAHS and GERD, and control (non-OSAHS and non-GERD), but no linear relationship between LES residual pressure and prevalence or severity of the two diseases was found. In OSAHS group, AHI were positively correlated with the following indictors: the DeMeester score (r = 0.45), acid exposure of the distal esophagus (r = 0.491). There seems to be no Linear correlation among reflux indicators, sleep indicators, and esophageal functional indicators in GERD group. Linear correlation was not found among reflux indicators, sleep indicators, and esophageal functional indicators in OSAHS and GERD group (P > 0.05).

CONCLUSIONSThe incidence and the severity of GERD and OSAHS were related to each other. Reflux events may aggravate OSAHS. The two diseases may have some relationship on the esophageal function, especially on the regulation of the LES pressure.

Adult ; Aged ; Electric Impedance ; Esophagus ; physiopathology ; Gastroesophageal Reflux ; physiopathology ; Humans ; Manometry ; Middle Aged ; Sleep Apnea, Obstructive ; physiopathology ; Stomach ; physiopathology ; Young Adult

OBJECTIVETo study the relationship between obstructive sleep apnea hypopnea syndrome (OSAHS) and nocturnal laryngopharyngeal reflux (LPR), and discuss the possible mechanism.

METHODSNineteen OSAHS patients had PSG, nocturnal pH and intraesophageal pressure monitoring simultaneously. The sleep stage, body position and pressure change were recorded during every reflux event The relationship between obstructive sleep apnea (OSA) and LPR was analyzed.

RESULTSAmong 19 OSAHS patients, 6 cases were found to have LPR, and 63 reflux events were recorded. There was a negative relationship between the severity of OSAHS and nocturnal mean laryngopharyngeal pH value, but relationship between OSA and reflux events is not statistically significant. The intraesophageal pressure (t = 3.211, P = 0. 007) and upper esophageal sphincter (UES) pressure (t = 2.234, P = 0.046) were statistically different between the patients with and without LPR. There was a positive relationship between the mean value of intraesophageal pressure and the whole night mean laryngopharyngeal pH value (r = 0.592, P = 0.033).

CONCLUSIONSThere was significant relationship between severity of OSAHS and nocturnal laryngopharyngeal pH value. OSAHS patients are more likely to have esophageal reflux which could increase LPR, Compared with OSAHS patients without LPR, UES pressure during the night decreased significantly in those cases with LPR, it suggested this could be another mechanism of LPR.

Adult ; Esophagus ; physiopathology ; Humans ; Hydrogen-Ion Concentration ; Hypopharynx ; physiopathology ; Laryngopharyngeal Reflux ; physiopathology ; Male ; Middle Aged ; Polysomnography ; Sleep Apnea, Obstructive ; physiopathology ; Sleep Stages

OBJECTIVEAim of this study was to investigate functions of lower esophageal sphincter (LES) barrier and esophageal clearance in fasting and postprandial stages in gastroesophageal reflux disease (GERD).

METHODSEight patients with confirmed GERD and 8 healthy subjects (HS) were observed in the study. The esophageal pH and manometry were recorded simultaneously for 1 h during fasting and 2 h after a meal (1,675 kJ) using pneumohydrolic capillary perfusion system.

RESULTS(1) The esophageal pH monitoring showed that median of percentage of pH < 4 at postprandial in HS and patients with GERD was 0.45% and 11.2%, respectively (P < 0.05). (2) Pressure of lower esophageal sphincter (LESP) significantly decreased after a test meal in GERD (P < 0.001) and in HS (P < 0.001). (3) The amplitude of post-LES relaxation related to swallow (post-LESRA) in GERD was much lower than in HS either during fasting or postprandial stage (P < 0.05). (4) The tension of crural diaphragm at resting (Dia-A0) in GERD was lower than in HS during fasting and postprandial stage(P < 0.05). (5) The tension of crural diaphragm at deep inspiration (dia-AM) in GERD and HS increased 3 or 4 times at pressure at gastroesophageal junction (GEJ). (6) The peristaltic amplitude of the distal esophagus in GERD were much lower than that in HS in both pre- and postprandial periods.

CONCLUSIONS(1) Impaired clearance of Post-LESRA and esophageal body, function of diaphragmatic crural play an important role in development of GERD. (2) The tension of crural diaphragm at deep inspiration can increase the pressure at GEJ.

Adolescent ; Adult ; Aged ; Diaphragm ; physiopathology ; Esophagogastric Junction ; physiopathology ; Esophagus ; physiopathology ; Gastroesophageal Reflux ; physiopathology ; Humans ; Hydrogen-Ion Concentration ; Manometry ; Middle Aged ; Peristalsis

OBJECTIVETo investigate the effects of peroral endoscopic myotomy(POEM) on esophageal dynamics in patients with esophageal achalasia.

METHODSFrom September 2011 to November 2011, 20 cases with esophageal achalasia received POEM at the Endoscopic Center in the Zhongshan Hospital of Fudan University. Pre-operation esophageal dynamics of all the patients were evaluated by high resolution manometry(HRM) system and 3 days after operation the test was repeated. Lower esophagus sphincter resting pressure(LESP), 4-second integrated relaxation pressure(4sIRP), lower esophagus sphincter relax rate(LESRR), lower esophagus sphincter length(LESL), and esophageal manometry were analyzed.

RESULTSAfter POEM, LESP decreased from(29.1±17.0) mm Hg to(14.6±4.9) mm Hg, and decrease rate was 49.8%(P<0.01). However, the decreases in LESRR and LESL were not statistically significant(P>0.05). Esophageal peristaltic contraction was absent in all the 20 patients preoperatively. After POEM, changes in the esophageal contraction were seen in 7 patients, and peristalsis was noticed but was below normal level. There were no significant changes in peristalsis in the remaining 13 patients.

CONCLUSIONPOEM can significantly reduce LESP and 4sIRP in patients with achalasia, but can not affect the contraction of the esophagus.

Adolescent ; Adult ; Aged ; Esophageal Achalasia ; physiopathology ; surgery ; Esophagoscopy ; methods ; Esophagus ; physiopathology ; surgery ; Female ; Humans ; Male ; Middle Aged ; Young Adult

OBJECTIVETo study the relationship between esophageal motor functional disorder [decreased lower esophageal sphincter pressure (LESP)and ineffective motility (IEM)] and gastroesophageal reflux disease (GERD).

METHODSTotally 89 patients with GERD were enrolled in this study. All of them underwent 24-hour pH monitoring with dual-channel probe and stationary esophageal manometry. In addition, 77 of these patients underwent upper endoscopy.

RESULTSIEM and LES, 10 mmHg were common disturbances in patients with GERD (54% and 48%, respectively). The number of the acid reflux events of distal esophagus and prevalence of moderate or severe erosive esophagitis (EE) were significantly higher in patients with low LESP and IEM than patients without low LESP ( P<0.05). The number of the acid reflux events in distal esophagus was significantly correlated with the severity of esophagitis, distal esophagus amplitude, and LESP, while no such correlation was found between IEM and degree of esophageal acid exposure or esophagitis.

CONCLUSIONSThe pathophysiology of GERD is probably multifactorial. Lower LESP or IEM is not a independent pathophysiological factor for GERD. However,one single factor is insufficient to explain all the pathogenic mechanism of GERD.

Adult ; Aged ; Aged, 80 and over ; Esophagus ; physiopathology ; Female ; Gastroesophageal Reflux ; physiopathology ; Humans ; Kinetics ; Male ; Middle Aged ; Young Adult

BACKGROUNDObstructive sleep apnea/hypopnea syndrome (OSAHS) and laryngopharyngeal reflux (LPR) disease have a high comorbidity rate, but the potential causal relation between the two diseases remains unclear. Our objectives were to investigate the esophageal functional changes in OSAHS patients and determine whether OSAHS affects LPR by affecting esophageal functions.

METHODSThirty-six OSAHS patients and 10 healthy controls underwent 24-h double-probed combined esophageal multichannel intraluminal impedance and pH monitoring simultaneously with polysomnography. High-resolution impedance manometry was applied to obtain a detailed evaluation of pharyngeal and esophageal motility.

RESULTSThere were 13 OSAHS patients (36.1%) without LPR (OSAHS group) and 23 (63.9%) with both OSAHS and LPR (OSAHS and LPR group). Significant differences were found in the onset velocity of liquid swallows (OVL, P = 0.029) and the percent relaxation of the lower esophageal sphincter (LES) during viscous swallows (P = 0.049) between the OSAHS and control groups. The percent relaxation of LES during viscous swallows was found to be negatively correlated with upright distal acid percent time (P = 0.016, R = -0.507), and OVL was found to be negatively correlated with recumbent distal acid percent time (P = 0.006, R = -0.557) in the OSAHS and LPR group.

CONCLUSIONSOSAHS patients experience esophageal functional changes, and linear correlations were found between the changed esophageal functional parameters and reflux indicators, which might be the reason that LPR showed a high comorbidity with OSAHS and why the severity of the two diseases is correlated.

Adult ; Esophagus ; physiopathology ; Female ; Humans ; Laryngopharyngeal Reflux ; etiology ; Male ; Middle Aged ; Polysomnography ; Sleep Apnea, Obstructive ; complications ; physiopathology

Transient lower esophageal sphincter (LES) relaxation (TLESR) is defined as LES relaxation without a swallow. TLESRs are observed in both of the normal individuals and the patients with gastroesophageal reflux disorder (GERD). However, TLESR is widely considered as the major mechanism of the GERD. The new equipments such as high resolution manometry and impedance pH study is helped to understand of TLESR and the related esophageal motor activities. The strong longitudinal muscle contraction was observed during development of TLESR. Most of TLESRs are terminated by TLESR related motor events such as primary peristalsis and secondary contractions. The majority of TLESRs are associated with gastroesophageal reflux. Upper esophageal sphincter (UES) contraction is mainly associated with liquid reflux during recumbent position and UES relaxation predominantly related with air reflux during upright position. The frequency of TLESR in GERD patients seems to be not different compared to normal individuals, but the refluxate of GERD patients tend to be more acidic during TLESR.
Esophageal Sphincter, Lower/*physiology ; Esophagogastric Junction/physiology ; Esophagus/*physiology ; Gastroesophageal Reflux/*physiopathology ; Humans ; Muscle Relaxation/physiology