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PubMed1996

Effects of carbon dioxide insufflation for laparoscopic cholecystectomy on the respiratory system.

The changes occurring in total respiratory system, lung and chest wall mechanics, lung volume and gas-exchange during abdominal insufflation with carbon dioxide for laparoscopic cholecystectomy were studied. Using the technique of rapid airway occlusion during constant flow inflation together with an oesophageal balloon, we computed compliance and maximum resistance of the respiratory system, subsequently apportioning it into its lung and chest wall components. Maximum resistance of the respiratory system was further divided into airway resistance and the viscoelastic properties of the lung and the chest wall. In 10 patients (group 1), we measured respiratory system, lung and chest wall mechanics (compliance and resistance), functional residual capacity, end-tidal carbon dioxide tension and oxygen saturation. In addition, arterial blood gas analysis and end-tidal carbon dioxide tension were measured in a second group of 10 patients (group 2). Measurements, in both groups, were obtained in the reverse Trendelenburg position, at 15 min after the induction of anaesthesia, 5 min and 45 min after abdominal insufflation and at 15 min after abdominal deflation. Tidal volume, respiratory rate, inspiratory flow and the fraction of inspired oxygen were similar in both groups and maintained constant during the procedure. We found that abdominal carbon dioxide insufflation caused: a reduction in compliance of the respiratory system (both lung and chest wall components) and of functional residual capacity; a marked increase in the maximum resistance of the respiratory system (mainly due to increases in the viscoelastic properties of the lung and chest wall); no change in oxygenation, but an increase in the end-tidal carbon dioxide tension (which was correlated closely with the arterial carbon dioxide tension). These changes were not affected by the duration of anaesthesia.

Abdomen↗
PubMed1989

The effect of general anaesthesia on the haemodynamic events during laparoscopy with CO2-insufflation.

Sixteen women were studied during elective diagnostic laparoscopy with CO2-insufflation to an intraabdominal pressure (IAP) of 2 kPa and Trendelenburg tilt to 30 degrees. They were allocated to either a halothane (Group I) or a balanced (Group II) anaesthesia with relaxation and controlled ventilation. Heart rate (HR), arterial pressure, stroke volume, CO2-elimination, end-tidal CO2 vol.% and total respiratory compliance (TRC) were the parameters measured, and mean arterial pressure (MAP), total peripheral resistance (TPR), stroke index (SI) and cardiac index (CI) were calculated. At maximum haemodynamic strain, SI and CI were on average reduced by 42% in both groups, without significant changes in HR and MAP. TPR increased by 50% in Group I and 100% in Group II. The reduction in SI was related to the changes in TRC. A small increment in CO2-elimination after CO2-insufflation was most pronounced in Group II. SI and CI did not reach the pre-insufflation values after return to the horizontal position and CO2-exsufflation. The haemodynamic differences between the two groups were small compared to the effects of the laparoscopy procedures.

Adolescent↗
PubMed1998

Myocardial hemodynamic and metabolic changes during abdominal insufflation with carbon dioxide.

It is a well-known fact that laparoscopic procedures performed with carbon dioxide insufflation impair myocardial function. In this study, we aimed to determine the safety limitations of various intra-abdominal pressure values during abdominal insufflation with carbon dioxide. Of the 24 mongrel dogs, 6 were assigned to one of four different pressure groups (10, 15, 20 and 30 mm Hg), respectively. Cardiac output, right/left heart pressures, and the first derivative of ventricular pressure were monitored. Myocardial oxygen consumption, myocardial lactate/oxygen extraction, tissue lactate and adenosine triphosphate levels were determined. Measurements were performed initially as a control, at 15-min intervals during 1 h of insufflation and 1 h after desufflation. At 10 mm Hg carbon dioxide pressure, hemodynamic and metabolic parameters were not significantly different. Cardiac output decreased significantly in the 20 and 30 mm Hg groups (p < 0.05: 10, 15 vs. 20, 30 mm Hg). Although cardiac output did not change at 15 mm Hg, the dp/dt value was significantly reduced. Cardiac output at the 60th min was 1,960+/-75 ml/min in the 10 mm Hg group, 1,885+/-40 ml/min in the 15 mm Hg group, 1,770+/-45 ml/min in the 20 mm Hg group and 1,695+/-40 ml/min in the 30 mm Hg group. Myocardial oxygen consumption was reduced at 15, 20 and 30 mm Hg (p < 0.05: 10 vs. 15, 20 and 30 mm Hg). In the myocardial tissue, ATP decreased from 19+/-2 to 12+/-1.2 micromol/g at 15 mm Hg, from 19+/-1.9 to 9.4+/-1.3 micromol/g at 20 mm Hg and from 18+/-3.2 to 8.2+/-1.9 micromol/g at 30 mm Hg. Changes in hemodynamic and metabolic parameters of the heart are reversible and may not lead to any significant impairments in patients having normal cardiopulmonary function, but pose a risk in patients with respiratory disease and limited myocardial reserve.

Abdomen↗
PubMed2004

Effect of CO2 insufflation on the number and behavior of air microemboli in open-heart surgery: a randomized clinical trial.

BACKGROUND: The risks that the presence of air microemboli implies in open-heart surgery have recently been emphasized by reports that their number is correlated with the degree of postoperative neuropsychological disorder. Therefore, we studied the effect of CO2 insufflation into the cardiothoracic wound on the incidence and behavior of microemboli in the heart and ascending aorta. METHODS AND RESULTS: Twenty patients undergoing single-valve surgery were randomly divided into 2 groups. Ten patients were insufflated with CO2 via a gas diffuser, and 10 were not. Microemboli were ascertained by intraoperative transesophageal echocardiography (TEE) and recorded on videotape from the moment that the aortic cross-clamp was released until 20 minutes after end of cardiopulmonary bypass (CPB). The surgeon performed standard de-airing maneuvers without being aware of TEE findings. Postoperatively, a blinded assessor determined the maximal number of gas emboli during each consecutive minute in the left atrium, left ventricle, and ascending aorta. The 2 groups did not differ in the usual clinical parameters. The median number of microemboli registered during the whole study period was 161 in the CO2 group versus 723 in the control group (P<0.001). Corresponding numbers for the left atrium were 69 versus 340 (P<0.001), left ventricle 68 versus 254 (P<0.001), and ascending aorta 56 versus 185 (P<0.001). In the CO2 group, the median number of detectable microemboli after CPB fell to zero 7 minutes after CPB versus 19 minutes in the control group (P<0.001). CONCLUSIONS: Insufflation of CO2 into the thoracic wound markedly decreases the incidence of microemboli.

Aged↗
PubMed2005

The effects of intraabdominally insufflated carbon dioxide on hepatic blood flow during laparoscopic surgery assessed by transesophageal echocardiography.

Conflicting results have been published about the effects of carbon dioxide (CO(2)) pneumoperitoneum on splanchnic and liver perfusion. Several experimental studies described a pressure-related reduction in hepatic blood flow, whereas other investigators reported an increase as long as the intraabdominal pressure (IAP) remained less than 16 mm Hg. Our goal in the present study was to investigate the effects of insufflated CO(2) on hepatic blood flow during laparoscopic surgery in healthy adults. Blood flow in the right and middle hepatic veins was assessed in 24 patients undergoing laparoscopic surgery by use of transesophageal Doppler echocardiography. Hepatic venous blood flow was recorded before and after 5, 10, 20, 30, and 40 min of pneumoperitoneum, as well as 1 and 5 min after deflation. Twelve patients undergoing conventional hernia repair served as the control group. The induction of pneumoperitoneum produced a significant increase in blood flow of the right and middle hepatic veins. Five minutes after insufflation of CO(2) the median right hepatic blood flow index increased from 196 mL/min/m(2) (95% confidence interval (CI), 140-261 mL/min/m(2)) to 392 mL/min/m(2) (CI, 263-551 mL/min/m(2)) (P < 0.05) and persisted during maintenance of pneumoperitoneum. In the middle hepatic vein the blood flow index increased from 105 mL/min/m(2) (CI, 71-136 mL/min/m(2)) to 159 mL/min/m(2) (CI, 103-236 mL/min/m(2)) 20 min after insufflation of CO(2). After deflation blood flow returned to baseline values in both hepatic veins. Conversely, in the control group hepatic blood flow remained unchanged over the entire study period. We conclude that induction of CO(2) pneumoperitoneum with an IAP of 12 mm Hg is associated with an increase in hepatic perfusion in healthy adults.

Adult↗
PubMed1992

Predictive value of objective esophageal insufflation testing for acquisition of tracheoesophageal speech.

This prospective study was undertaken to assess the predictive value of esophageal insufflation on the acquisition of tracheoesophageal (TE) speech. Fourteen total laryngectomy patients were evaluated prior to tracheoesophageal puncture (TEP) using objective esophageal pressure measurements. These patients then were followed prospectively for 6 to 13 months. Speech was assessed at the time of prosthesis fitting, at 1 month, at less than 6 months, and at greater than 6 months post-TEP. No patient underwent pharyngeal myotomy. Pre-TEP esophageal insufflation pressure was associated (P = .065) with successful TE speech at the time of prosthesis fitting, but was not associated with successful TE speech acquisition after 6 months. This study's results suggest that patients with poor pre-TEP esophageal insufflation test results will usually obtain successful TE speech given adequate time and training, even without pharyngeal myotomy.

Aged↗
PubMed1993

Mechanical insufflation-exsufflation. Comparison of peak expiratory flows with manually assisted and unassisted coughing techniques.

Pulmonary complications are major causes of morbidity and mortality for patients with severe expiratory muscle weakness. The purpose of this study was to compare peak cough expiratory flows (PCEFs) during unassisted and assisted coughing and review the long-term use of mechanical insufflation-exsufflation (MI-E) for 46 neuromuscular ventilator users. These individuals used noninvasive methods of ventilatory support for a mean of 21.1 h/d for 17.3 +/- 15.5 years. They relied on manually assisted coughing and/or MI-E during periods of productive airway secretion. They reported a mean of 0.7 +/- 1.2 cases of pneumonia and other serious pulmonary complications and 2.8 +/- 5.6 hospitalizations during the 16.4-year period and no complications of MI-E. A sample of 21 of these patients with a mean forced vital capacity of 490 +/- 370 ml had a mean maximum insufflation capacity (MIC) achieved by a combination of air stacking of ventilator insufflations and glossopharyngeal breathing of 1,670 +/- 540 ml. The PCEFs for this sample were: following an unassisted inspiration, 1.81 +/- 1.03 L/s; following a MIC maneuver, 3.37 +/- 1.07 L/s; with manual assistance by abdominal compression following a MIC maneuver, 4.27 +/- 1.29 L/s; and with MI-E, 7.47 +/- 1.02 L/s. Each PCEF was significantly greater than the preceding, respectively (p < 0.01). We conclude that manually assisted coughing and MI-E are effective and safe methods for facilitating airway secretion clearance for neuromuscular ventilator users who would otherwise be managed by endotracheal suctioning. Severely decreased MIC, but not necessarily vital capacity, is an indication for tracheostomy.

Adult↗
PubMed2004

Efficacy of mechanical insufflation-exsufflation in medically stable patients with amyotrophic lateral sclerosis.

OBJECTIVE: To determine under what circumstances the use of mechanical insufflation-exsufflation (MI-E) can generate clinically effective expiratory flows for airway clearance (> 2.7 L/s) for clinically stable patients with amyotrophic lateral sclerosis (ALS). MATERIALS AND METHOD: Twenty-six consecutive patients with ALS were studied, 15 with severe bulbar dysfunction. Using a pneumotachograph and with the aid of an oronasal mask, we measured FVC, FEV(1), peak cough flow (PCF), maximum insufflation capacity (MIC), PCF generated from a maximum insufflation MIC (PCFMIC), and PCF generated by MI-E (PCFMI-E). MI-E was delivered at +/- 40 cm H(2)O. Maximum inspiratory pressure (PImax) and maximum expiratory pressure (PEmax) at the mouth were also measured. RESULTS: Although both groups had a similar time from ALS symptom onset to diagnosis, statistical differences (p < 0.05) were found between nonbulbar and bulbar patients in lung function and cough capacity parameters: FVC, 2.58 +/- 1.24 L vs 1.62 +/- 0.74 L; FEV(1), 2.26 +/- 1.18 L vs 1.54 +/- 0.69 L; PImax, - 93.45 +/- 47.47 cm H(2)O vs - 3.64 +/- 25.07 cm H(2)O; PEmax, 140.45 +/- 75.98 cm H(2)O vs 69.93 +/- 32.14 cm H(2)O; MIC, 3.02 +/- 1.22 L vs 1.97 +/- 0.75 L; PCF, 5.91 +/- 2.55 L/s vs 3.42 +/- 1.44 L/s; PCFMIC, 6.68 +/- 2.71 L/s vs 4.00 +/- 1.48 L/s; and PCFMI-E, 4.34 +/- 0.82 L/s vs 3.35 +/- 0.77 L/s. Four patients with bulbar dysfunction and MIC > 1 L had PCFMI-E < 2.7 L/s. The receiver operating characteristic (ROC) curve analysis showed PCFMIC of 4 L/s predicting those patients with PCFMIC greater than PCFMI-E. CONCLUSION: MI-E is able to generate clinically effective PCFMI-E (> 2.7 L/s) for stable patients with ALS, except for those with bulbar dysfunction who also have a MIC > 1 L and PCFMIC <2.7 L/s who probably have severe dynamic collapse of the upper airways during the exsufflation cycle. Clinically stable patients with mild respiratory dysfunction and PCFMIC > 4 L/s might not benefit from MI-E except during an acute respiratory illness.

Amyotrophic Lateral Sclerosis↗
PubMed2001

Animal and lung model studies of tracheal gas insufflation.

Tracheal gas insufflation (TGI) is the continuous or phasic insufflation of fresh gas into the central airways for the purpose of improving the efficiency of alveolar ventilation and/or minimizing the ventilatory pressure requirements. Fresh gas is insufflated near the main carina, usually at flow rates of 2-15 L/min. During expiration, TGI clears the anatomic and apparatus dead space proximal to the catheter tip, thus improving carbon dioxide (CO2) clearance. Moreover, at high catheter flow rates turbulence generated at the tip of the catheter may enhance distal gas mixing. CO2 elimination during TGI depends on catheter flow rate, as at higher flow rates a greater portion of the proximal dead space is flushed clear of CO2. Consequently, as TGI flow is increased, arterial carbon dioxide tension (PaCO2) decreases. Eventually, with increasing catheter flow rate, fresh gas completely flushes the available dead space during expiration and the PaCO2 reaches a plateau. At that point, increasing catheter flow rate decreases PaCO2 much less, probably because of turbulent mixing in the airways distal to the catheter tip. In clinical practice, TGI can be applied either to decrease PaCO2 while maintaining tidal volume constant or to decrease tidal volume while keeping PaCO2 constant. In the former strategy, TGI is used to protect pH, whereas in the latter it is used to minimize the stretch forces acting on the lung parenchyma, to minimize ventilator-associated lung injury.

Animals↗
PubMed2001

Monitoring and humidification during tracheal gas insufflation.

In order to use tracheal gas insufflation (TGI) in a safe and effective manner, it is important to understand potential interactions between TGI and the mechanical ventilator that may impact upon gas delivery and carbon dioxide (CO2) elimination. Furthermore, potentially serious complications secondary to insufflation of cool, dry gas directly into the airway and the possibility of tube occlusion must be considered during use of this adjunct modality to mechanical ventilation. Regardless of the delivery modality (continuous TGI, expiratory TGI, reverse TGI, or bidirectional TGI), conventional respiratory monitoring is required. However, TGI with mechanical ventilation can alter tidal volume and peak inspiratory pressure and can lead to the development of intrinsic positive end-expiratory pressure. Therefore, depending on the gas delivery technique used, it is important to carefully monitor these ventilatory parameters for TGI-induced changes and understand the potential need for adjustments to ventilator settings to facilitate therapy and avoid problems. Optimally, gas insufflated by the TGI catheter should be conditioned by addition of heat and humidity to prevent mucus plug formation and potential damage to the tracheal mucosa. Finally, patients must be closely monitored for increases in peak inspiratory pressure from obstruction of the tracheal tube and should have the TGI catheter removed and inspected every 8-12 hours to assess for plugs.

Airway Resistance↗
PubMed2001

Right vs left side thoracoscopic sympathectomy: effects of CO2 insufflation on haemodynamics.

BACKGROUND AND AIMS: Currently, few reports of the haemodynamic impact of intrapleural CO2 insufflation in the clinical setting are available. Therefore, we conducted the present study to compare the haemodynamic changes between right and left side thoracoscopic sympathectomy (TS) for treatment of palmar hyperhidrosis (PH) under general anaesthesia. MATERIALS AND METHODS: 20 adult patients (17 males) undergoing TS were randomly allocated to two groups (each 10); group A, right side and group B, left side TS procedures were performed under general anaesthesia with single-lumen endotracheal tube. Besides the routine monitoring of vital signs, non-invasive cardiac output monitor (NICO) was used to record the stroke volume (SV), cardiac output (CO) and cardiac index (CI). Intrapleural CO2 insufflation was used. Anaesthesia was maintained with 1 MAC sevoflurane in 50% nitrous oxide in oxygen with incremental doses of sufentanil and atracurium when required. Haemodynamic parameters were obtained every 3 min then averaged over the time of surgery at phases; I) after tracheal intubation, II) after CO2 insufflation and III) after CO2 deflation. RESULTS: The CO, CI and SV showed decreased trend in both groups during phase II compared to phase I with significant differences (P < 0.05). Comparing the CO and CI variables revealed lower values in group A compared to group B but with non-significant differences (P > 0.05). While the SV variable showed significant low value in group A compared to group B (P < 0.05). CONCLUSIONS: Compared to left side TS, direct compression by CO2 against the venae cava and right atrium and ventricle during right side TS caused reduction of the venous return and hence low CO, CI and SV.

Adult↗
PubMed1990

[Acute intestinal intussusception: ultrasonic diagnosis and air insufflation].

Sixty-five children with intussusception were diagnosed by ultrasonography. Colonic air insufflation was the principle form of treatment. The diagnosis value of ultrasound was 100% and the success rate of reduction by air insufflation was 93%, after intrarectal injection of midazolam (0.3 mg/kg). The device for insufflation was simple, original and manual, with permanent control of intrarectal pressure. No complications were observed.

Acute Disease↗
PubMed1993

Comparison of insufflated talc under thoracoscopic guidance with standard tetracycline and bleomycin pleurodesis for control of malignant pleural effusions.

The standard palliation of malignant pleural effusions involves tube thoracostomy drainage with chemical pleurodesis. The insufflation of intrapleural talc under thoracoscopic guidance (n = 39) was evaluated against documented controls that consisted of patients (n = 85) who participated in a randomized study with tube thoracostomy drainage followed by either bleomycin or tetracycline sclerosis. Under local anesthesia, which was supplemented by intravenous sedation, patients in the talc group underwent complete pleural fluid evacuation. The talc was then insufflated evenly on the entire pleural surface under thoracoscopic guidance. Of the patients in the talc group who survived their disease process, 97% had a successful pleurodesis at 30 days and 95% at 90 days. In comparison, the bleomycin group demonstrated a success rate of 64% at 30 days and 70% at 90 days (p = 0.003 and p = 0.047 versus the talc group). The tetracycline group had successful pleurodesis in only 33% at 30 days and 47% at 90 days (p < 0.001 and p < 0.001 versus the talc group). There were only two patients in the talc group in whom pleurodesis was not successful, and both were subsequently found to have extraluminal compression of the right lower lobe bronchus, which prevented lung reexpansion. These data demonstrate that the insufflation of talc into the pleural cavity under thoracoscopic guidance is a safe and efficacious procedure in the control of malignant pleural effusions.

Adult↗
PubMed1994

A new insufflation needle with a special optical system for use in laparoscopic procedures.

A new insufflation needle with a special optical system consisting of a transparent, conical tip, to which an endoscope can be attached, allows perforation of the abdominal wall under direct vision. A video camera can be attached to the instrument, so that its progress through the abdominal wall can be observed on a monitor. The danger of damage to vessels and intra-abdominal organs associated with blind insertion of the insufflation needle is thus avoided. There is also no risk of insufflation of the properitoneal space because the exact position of the needle tip is known. Use of this new instrument could further improve the safety of laparoscopic procedures.

Female↗
PubMed1993

Helium insufflation for laparoscopic operation.

Laparoscopic surgical procedures are becoming simultaneously more commonplace and complex. However, carbon dioxide (CO2) pneumoperitoneum required for these procedures causes a respiratory acidosis. We undertook this study to determine if an alternate insufflating gas, such as helium, prevents this sequelae. Twenty patients undergoing elective laparoscopic cholecystectomy were randomized to receive either CO2 or helium insufflation. Intraoperative parameters, including arterial CO2 (PaCO2), end-tidal CO2, pH, bicarbonate (HCO3-), cardiac output and blood pressure were obtained before, during and at the conclusion of pneumoperitoneum. Effects of the two gases on these variables were compared. The average CO2 rose significantly from 35.7 +/- 1.0 to 50.4 +/- 3.2 (p < 0.0001), while pH decreased from 7.434 +/- 0.014 to 7.286 +/- 0.018 (p < 0.0001) in those who received CO2. No change in PaCO2 was observed in those who received He, although a small decrease in pH from 7.428 +/- 0.011 to 7.392 +/- 0.012 (p < 0.05) was observed. HCO3- decreased slightly in both groups. Increases in blood pressure and pulse rate were independent of the gas received. The cardiac output did not change. Helium insufflation for laparoscopic cholecystectomy does not produce the respiratory acidosis caused by CO2 and, therefore, merits further investigation for use, particularly in patients with underlying respiratory disease.

Adult↗
PubMed1995

Helium insufflation in laparoscopic surgery.

Carbon dioxide is the most commonly used gas for abdominal insufflation in laparoscopy today. Due to the solubility of carbon dioxide large volumes are absorbed into the circulation causing a high PCO2 and a low pH (respiratory acidosis). Carbon dioxide is also stored in several sites in the body and is released at the conclusion of the procedure prolonging the respiratory acidosis when the patient is least able to cope with this additional burden. Cardiac effects of CO2 consist of a lowering of the arrhythmia threshold, increased blood pressure, pulse and cardiac output. At a sustained high level this can lead to cardiac depression and death. These effects are particularly prone to occur in cardiac and respiratory cripples. Other gases that have been used include air, oxygen, nitrous oxide and nitrogen. Their use has been discontinued because of the danger of embolism. Air, oxygen and nitrous oxide are also not safe to use in the presence of electrosurgical instruments thereby limiting their usefulness even further. Helium has been proposed as a very promising alternative to CO2. In the laboratory and in a clinical trial, helium has not produced the respiratory acidosis associated with CO2 insufflation. This is further evidence that the acidosis is not primarily due to elevation of the diaphragm and consequent increased dead space, but to the large amount of CO2 that is absorbed directly from the peritoneal cavity. Helium would seem to be the gas of choice at this time as it comes close to fitting the criteria for an ideal insufflating gas. Helium is clear and colorless, allowing unimpeded vision to the operator. It is non toxic, not flammable or explosive and can be safely used with electrocautery and laser. Helium is easy to handle and not very soluble which decreases the amount absorbed from the peritoneal cavity and consequently the amount used. That which is absorbed is quickly cleared by the lungs. Helium is metabolically inactive (in contrast to CO2) and does not interfere with normal metabolic processes. In view of this promising initial work, further studies are indicated.

Abdomen↗
PubMed1997

Laparoscopic hypothermia: heat loss from insufflation gas flow.

To determine the effects of laparoscopic gas flow on intraoperative hypothermia, we measured heat loss from intra-abdominally heating cold insufflation gas and intra-abdominal evaporative heat losses. Heat loss from heating insufflated CO2 was 304 L/Cal; evaporative loss was 109 L/Cal. Even in the worst hypothetical case of complete water saturation of dry insufflated gas, total heat loss would total 81 L/Cal, a relatively minor contribution to surgical hypothermia.

Abdomen↗
PubMedDate not supplied

Abdominal pseudotumors and simulated lymphadenopathy in MRI: differential features with the use of retrograde air insufflation.

In order to evaluate the contribution of retrograde air insufflation in decreasing the occurrence of pseudotumor appearance and mimicked lymphadenopathy due to nonair-distended bowel loops, we retrospectively compared two groups of magnetic resonance (MR) examinations. In the group receiving retrograde air insufflation, 10.8% (67 of 619) of images showed a tumor-like lesion due to nonair-distended bowel loop(s), whereas in the group not receiving air introduction, a tumor-like lesion was simulated in 45.6% (140 of 307) of images. Furthermore, a collapsed bowel loop(s) mimicking an enlarged lymph node close to the aorta, inferior vena cava, or bilateral iliac vessels was found in 9.5% (24 of 252) of images of the latter group, in contrast to only 1.8% (9 of 505) of images of the former group. This study shows that retrograde air insufflation greatly reduces the occurrence of pseudotumor appearance and false impression of paraaortic, paracaval, or parailiac lymphadenopathy secondary to nonair-distended bowel loop(s).

Abdomen↗