Idiopathic interstitial pulmonary fibrosis (IPF) is considered the most common form of interstitial lung disease (ILD). Its course is a progressive of and its cause is unknown. Idiopathic interstitial pulmonary fibrosis affect the gas exchange as it results in chronic inflammation and progressive fibrosis of lung parenchyma. The signs and symptoms of this disease consist of progressive dyspnea, hypoxia, clubbing and crepitations at the lung bases [1].

IPF is a fatal lung disease; the natural history is variable and unpredictable: Most patients with IPF demonstrate a gradual worsening of lung function over years; a minority of patients remains stable or declines rapidly. Some patients may experience episodes of acute respiratory worsening despite previous stability.

The diagnosis of IPF is based on the absence of a known cause of lung fibrosis, computed tomography (CT) findings and, in cases with CT abnormalities that are not classical for IPF, the use of pathological criteria [2].

IPF is defined as a specific form of chronic, progressive fibrosing interstitial pneumonia of unknown cause, occurring primarily in older adults, limited to the lungs, and associated with the histopathologic and/or radiologic pattern of unspecified interstitial pneumonia (UIP) [3].

• 1. Exclusion of other known causes of interstitial lung disease (ILD) The presence of a unspecified interstitial pneumonia (UIP) pattern on high-resolution computed tomography (HRCT) in patients not subjected to surgical lung biopsy.

• 2. Specific combinations of HRCT and surgical lung biopsy pattern in patients subjected to surgical lung biopsy.

The accuracy of the diagnosis of IPF increases with multidisciplinary discussion between pulmonologists, radiologists, and pathologists experienced in the diagnosis of ILD.

We report 59-yr-old, female with severe Idiopathic pulmonary fibrosis (IPF) undergoing laparoscopic cholecystectomy because of acute inflammation of gall bladder.

The patient underwent preoperative assessment by history taking, Physical examination and preoperative laboratory investigations which include (complete blood count, liver function, blood urea and creatinine, fasting and postprandial blood sugar, prothrombin time and activity and arterial blood gas, ECG, and echocardiography).

The medical history of the patients revealed that, the patients had controlled hypertension and diabetes mellitus which controlled by insulin.

The laboratory investigations revealed the following: leukocytosis WBC 18000/ML, PO₂ 60 mmHg and O₂ saturation 90% on air, otherwise no abnormalities were found. Pulmonary function test was done and revealed severe restrictive pattern of pulmonary function as FEV1/VC 115%. The chest X-ray (Figure 1) showed bilateral lung infiltration and loss of lung volume.

Figure 1: The chest X-ray (antero-posterior) showed bilateral lung infiltration and loss of lung volume.

We optimize the chest condition by bronchodilator, antibiotic, nebulization and corticosteroids 3 days before surgery.

The patient received 150 mg ranitidine and 10 mg of metoclopramide one hour before anesthesia.

On arrival to operating room an intravenous line was inserted. Patient was attached to monitor displaying ECG, HR, NIBP, ETCO₂ and O₂ saturation.

The patient received preoxygenation for 3 min before anesthesia, anesthesia was induced by fentanyl 2 ug/kg, propofol 2 mg/kg and cisatracurium 0.15 mg/kg, assisted ventilation was done for 3 min, the size 4 i-gel was inserted after lubricating the device with a water-based lubricant according to manufacturer's recommendations [4].

After insertion of the of the i-gel it was fixed by adhesive tape and we confirm the adequacy of ventilation by observing the raise of chest wall, chest auscultation, and presence of square wave of capnogram. 12F gasteric tube was inserted through gastric channel for gastric decompression and the gastric tube was connected to collection bag to drain freely during surgery.

Anesthesia was maintained with isoflurane in oxygen. The ventilator was adjusted to achieve SpO₂ ≤ 95% and end-tidal CO₂ of 32-35 mmHg through tidal volumes of 6 ml/kg, respiratory rate of 10-14/min and I:E ratio 1:1.5.

The intra-abdominal pressure was set at 12 mmHg for creation pneumoperitoneum to allow visualization of intraabdominal organs.

One hour after start of surgery, the O₂ saturation was decreased from 99% to 92%, and in an trial to overcome this event we changed the ventilator parameters as follow: inspiratory: expiratory ratio was changed to 1:1, increase the tidal volumes to 8 ml/kg after these modification of ventilator parameters, the O₂ saturation was increased to 98% and maintained till the end of operation.

After completion of surgery, residual neuromuscular block was antagonized with atropine 0.02 mg/kg and neostigmine 0.05 mg/kg. The i-gel airway device was removed once patient had spontaneous breathing, return of airway reflexes, spontaneous or on command eye opening and purposeful movement. The patient was transferred to the intensive care unit with no pain, no nausea or vomiting and O₂ saturation was 90% on room air increased to 98% on low flow O₂ 2 L/min by nasal cannula.

General anesthesia with endotracheal tube remains the best choice for laparoscopic cholecystectomy to protect the patients against pulmonary aspiration and respiratory distress as a result of increased intra-abdominal pressure during pneumoperitoneum [5].

Our findings suggest that the i-gel was a useful airway device alternative to tracheal intubation and PLMA for laparoscopic cholecystectomy in patient with severe interstitial pulmonary fibrosis.

The lung protective strategy was used in patients with pulmonary fibrosis, which include limit the inspiratory pressure to not more than 30 mmHg, limit the tidal volume to not more than 8 ml/kg to avoid barotrauma and volutrauma [6,7].

The i-gel was used in this case because of the following: No inflatable cuff which allow ease of insertion, decrease the risk of tissue damage, less post-operative sore throat, and no position change after insertion [8,9].

I-gel is beneficial because it reduces airway stimulation, decrease the risk for bronchospasm, protects against pulmonary aspiration because It provides better seal and the possibility insertion of gastric tube allows gastric drainage provide additional safety against regurgitation and aspiration.

Also, the i-gel is a single-use disposable device that reduces the risk of transfer of infectious material or body fluids compared with improperly cleaned reusable devices.

The disadvantages of supraglottic devices with inflatable cuff include, tissue distortion, venous compression, nerve injury, and increased incidence of postoperative morbidity [8].

The causes of postoperative morbidity of supraglottic devices with inflatable cuff include, Trauma during insertion, multiple attempts, pressure exerted by cuff against the pharyngeal mucosa, cuff volumes and cuff pressure (10-13).

Advantages of the i-gel over the PLMA include, better anatomic fit was achieved when compared to PLMA [14,15] faster and easy insertion with a low incidence of postoperative sore throat [16].

Advantages of the i-gel over the tracheal tube included: ease of placement; hemodynamic stability at induction and during recovery which benefit to patients with cardiovascular and respiratory disease; reduced anesthetic requirements; lower frequency of coughing during emergence; and lower incidence of pharyngolaryngeal morbidity. Also it results in smooth recovery from anaesthesia and less postoperative nausea, vomiting, airway morbidity, and analgesic requirements than the tracheal tube.

The incidence of postoperative sore throat after was less after supraglottic devices when compared to tracheal intubation which ranged from 30-70% after tracheal intubation so, supraglottic devices associated with more patients comfort and satisfaction.

Disadvantages of supraglottic devices were lower seal pressures and gastric insufflation.

The incidence of gastric distention and pulmonary aspiration during laparoscopic surgery may be increased because of increased intraabdominal pressure as result of pneumoperitoneum, head down position, peritoneal stimulation, and increase gastro-esophageal reflux.

My opinion about the incidence of gastric distention and pulmonary aspiration during laparoscopic surgery under general anesthesia with i-gel we believed that it is not increased when the i-gel was used as rescue airway which can explain by: the i-gel is truly anatomical device. The soft non inflatable cuff fits snugly on to the per laryngeal frame work, mirroring the shape of the epiglottis, aeryepiglottic folds, piriform fossae, perithyroid, pericricoid, posterior cartilages and spaces. The seal created is sufficient for both spontaneously breathing patients and for intermittent positive pressure ventilation. It provides a better seal for positive pressure ventilation, separation of the respiratory from the alimentary tract and the venting of gas or liquid via its unique drain port. The drain port allows placement of gastric tube for decompression of stomach during surgery [8].

The supraglottic devices were proved to be effective ventilator device in patients underwent laparoscopic surgery as follow:

The reported incidence of aspiration or more serious morbidity associated with the use of the LMA in laparoscopic surgery is very low which support our finding [17].

Moreover, Supreme laryngeal mask airway was proved to be a suitable alternative to intubation in laparoscopic surgical procedures [18].

Additionally Supreme laryngeal mask airway was used as airway device for laparoscopic cholecystectomy in patient with severe pulmonary fibrosis [19].

Also there was no evidence to suggest that the use of intermittent positive pressure ventilation via the laryngeal mask increases the risk of gastro-oesophageal reflux in patients undergoing gynaecological laparoscopy [20,21].

Both classic LMA and prosel LMA were used as airway management in patients undergoing laparoscopic cholecystectomy and both devices were suitable but The PLMA is a more effective airway device for laparoscopic cholecystectomy than the LMA [22].

Also there were no statistically significant differences in oxygen saturation or end tidal CO2 between the proseal LMA and tracheal intubation before or during pneumoperitoneum. With no gastric distension during surgery with proseal LMA in patients underwent laparoscopic cholecystectomy [23].

The i-gel is useful supraglottic device and can replace the need of tracheal intubation in elective laparoscopic cholecystectomy in patient with severe interstitial pulmonary fibrosis with no reported serious complications and low incidences of pharyngolaryngeal morbidity.

The authors have no conflict of interest.