Year : 2007 | Volume
: 51 | Issue : 3 | Page : 231--233
Capnothorax during laparoscopic cholecystectomy
Gunjan Manchanda1, Anju R Bhalotra2, Poonam Bhadoria3, Aarti Jain4, Preeti Goyal5, Mona Arya6,
1 DA, DNB, Specialist, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
2 MD, Assistant Professor, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
3 MD, Professor, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
4 MD, Senior Resident, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
5 PG Student, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
6 DA, Specialist, Department of Anaesthesia and Intensive Care, Maulana Azad Medical College, New Delhi - 110002, India
4LF, Todarmal Square, Bharakhamba Road, New Delhi - 110001
Laparoscopic procedures are becoming increasingly widespread as more and more surgical procedures are becoming amenable to laparoscopic repairs. As the spectrum of the procedures widens, so are the likely complications. It is imperative for the discerning anaesthesiologists to be vigilant for the possible complications related to this technique.
|How to cite this article:|
Manchanda G, Bhalotra AR, Bhadoria P, Jain A, Goyal P, Arya M. Capnothorax during laparoscopic cholecystectomy.Indian J Anaesth 2007;51:231-233
|How to cite this URL:|
Manchanda G, Bhalotra AR, Bhadoria P, Jain A, Goyal P, Arya M. Capnothorax during laparoscopic cholecystectomy. Indian J Anaesth [serial online] 2007 [cited 2020 May 28 ];51:231-233
Available from: http://www.ijaweb.org/text.asp?2007/51/3/231/61149
Over the last few decades, laparoscopy has become an indispensable tool for all types of surgeries and has evolved from a diagnostic modality to a method of performing complex surgical procedures. Laparoscopic cholecystectomy is becoming popular and has largely replaced the open surgical procedures. The advantages claimed for laparoscopic techniques include less postoperative pain, reduced hospital stay, a good cosmetic result and decreased morbidity.  However, with its increasing popularity and uses, the number and variety of complications associated with laparoscopic procedures are likely to increase. The main complications seem to be related to the insufflation of carbon dioxide gas. These include hypercarbia, subcutaneous emphysema, pneumothorax and pneumomediastinum.  Anaesthesiologists and surgeons should be aware of these complications and should be prepared to treat any haemodynamic and/or ventilatory problems.
We report a case of spontaneous right-sided capnothorax occurring during an otherwise uneventful laparoscopic cholecystectomy.
Laparoscopic cholecystectomy was performed on a 23-year-old non-smoker female patient (ASA I, height 155cm, weight 43 kg). After induction of general anaesthesia with pethidine and thiopentone, vecuronium was given to facilitate endotracheal intubation and the lungs were ventilated with 66% nitrous oxide and 0.5%-1% isoflurane in oxygen using an Ohmeda ventilator with a tidal volume of 450 ml at a rate of 12 breaths per minute. Chest inflation was adequate and equal and normal breath sounds were heard bilaterally. Neuromuscular block was maintained with intermittent doses of vecuronium and an oro-gastric tube was placed prior to creation of pneumoperitoneum.
Intraoperative monitoring included continuous electrocardiogram (ECG), heart rate (HR), noninvasive blood pressure (NIBP), arterial oxygen saturation by pulse oximetry (SpO2), end tidal carbon dioxide concentration (EtCO2), tidal volume, minute volume and airway pressures. After intubation, BP was 116/76 mmHg, HR 88/ min, EtCO2 35mmHg with SpO2 99% and airway pressure was 16cm of H2O.
With the patient in the supine position, a pneumoperitoneum of 12 mmHg was established with CO2 using an electronic variable flow, pressure-controlled insufflator.
The patient was then placed in a 40-degree reverse Trendelenburg position with right side up. Minute ventilation was increased from 4.5L to 6L during CO2 pneumoperitoneum to maintain EtCO2 at around 40 mm Hg. Despite the adjustment in minute ventilation EtCO2 increased to 48 mmHg towards the end of surgery. There was also a slight increase in peak inspiratory pressure (PIP) from 16 to 20 cm of H2 O. The patient's vital parameters remained within normal limits and SpO2 was around 96-97% at this time. The surgical procedure lasted for 110 minutes but was technically uneventful. At the end of surgery, the patient was returned to the horizontal position and the abdomen was desufflated. Residual neuromuscular blockade was antagonized and the patient's trachea was extubated.
Following extubation, despite good respiratory efforts SpO2 on room air was 88- 89%. Patient was given 100% oxygen by facemask at 4-5L/ min on which SpO2 increased to 99%. Decreased chest movements were then noticed on the right side. On auscultation air entry was found to be markedly reduced on the same side. A chest X-ray was done in the theatre, which revealed right-sided pneumothorax.
As the patient was fully conscious, haemodynamically stable and seemed comfortable, she was put on oxygen by ventimask with FiO2 0.5% at 4-5L/min and was shifted to the postoperative ward for further observation. The SpO2 gradually increased from 92% at FiO 2 0.5% to 96% over a period of 30 minutes. Air entry also improved over right chest.
After another one hour, bilateral air entry was equal and adequate. She was maintaining SpO2 99-100% on ventimask. A repeat chest X-ray was normal. The patient had an uneventful recovery and was discharged two days later by the surgical unit.
The incidence of pneumothorax/pneumomediastinum is 1.9% during any kind of laparoscopic surgery. However, the occurrence of a pneumothorax complicating laparoscopic cholecystectomy is very unusual.  Gas may enter the chest by a variety of routes. These include trauma to the diaphragm or falciform ligament, passage through congenital defects or foramina in the diaphragm or via a subperitoneal route. Pneumothorax, pneumomediastinum and surgical emphysema may also result from barotrauma or from rupture of an emphysematous bulla. 
Presence of congenital diaphragmatic defects producing a pleuroperitoneal communication is the most common explanation. According to Meyer the communication of pleural and peritoneal cavities closes in the third month of gestation.  Diaphragm forms from the fusion of septum transversum, dorsal and ventral mesenteries and the pleuroperitoneal membrane. Improper fusion of these structures or improper deposition of mesoderm at the points of union results in congenital weak points or defects in the diaphragm.  Opening of these pleuroperitoneal ducts results mainly in right-sided pneumothorax.  Gas insufflation through a perforated falciform ligament has also been proposed to cause pneumothorax during laparoscopic cholecystectomy by forcing gas into the mediastinum through the caval orifice of diaphragm.  A pneumothorax can also be due to rupture of preexisting bullae. Such a situation is more common in elderly chronic smoker patients with underlying chronic obstructive airway- disease. In this case there will be no increase in CO2 absorption and treatment required is different. Thoracocentesis is mandatory and PEEP must not be applied. 
A cephalad displacement of the diaphragm and carina after creating pneumoperitoneum during laparoscopic cholecystectomy can lead to endobronchial intubation and collapse of contralateral lung. Right-sided endobronchial intubation is more common leading to left lung collapse. This complication results in decrease in SpO 2 associated with an increase in plateau airway pressure.  EtCO 2 however may not rise markedly. Fibreoptic bronchoscopy can be done to rule out this complication. 
We have described a case of spontaneous unilateral carbon dioxide pneumothorax in a ASA grade 1 patient undergoing routine laparoscopic cholecystectomy. The first sign was a progressive increase in EtCO2 despite adjustments in minute ventilation. Aslight increase in airway pressures and decrease in SpO2 intraoperatively and inability to maintain SpO2 after extubation further support the diagnosis. Lack of breath sounds on auscultation over the right side of thorax and the chest X-ray confirmed the diagnosis of a pneumothorax. During CO2 pneumoperitoneum, CO2 absorption and subsequently EtCO2 progressively increase and then plateau after 20-30 minutes. Any change in this value after its steady state is reached, suggests a complication.  The initial increase in EtCO2 in this patient was probably only due to absorption of CO2 from subcutaneous tissues but a later rapid increase in EtCO2 accompanied by increase in PIP indicated capnothorax.
If a potential pneumothorax is suspected towards the end of surgery, it may be managed conservatively since the gas is highly soluble in blood and thus gets quickly absorbed from the pleural cavity after abdominal desufflation. , The procedure may be allowed to continue after cessation of nitrous oxide with close observation of cardiovascular and respiratory parameters as the insertion of chest tube is not without complications and its insertion can compromise maintenance of pneumoperitoneum and hence laparoscopy.  However, if there is massive pneumothorax with haemodynamic instability, recognized in the beginning or middle of laparoscopic procedure, then the abdomen should be deflated while tube thoracostomy is performed. Once the chest tube is in satisfactory position, then the abdomen can be reinsufflated and the procedure can be continued if the patient remains stable.  In the presence of a tension pneumothorax, standard therapeutic measures should be instituted including needle thoracostomy followed by placement of a chest tube.  Administration of nitrous oxide has to be discontinued when pneumothorax occurs to prevent or correct hypoxemia and to prevent a volume increase of pneumothorax. 
Laparoscopy for general surgery often involves longer procedures, larger insufflated volumes, different sites and degrees of dissection, different patient positions, older patients and often more inexperienced laparoscopists.  With this in mind all patients for general surgical laparoscopy should be carefully monitored. Pneumothorax remains a rare and occasionally reported complication. It should be remembered that capnothorax can occur even without pulmonary or pleural trauma. Factors that predispose to development of pneumothorax include high CO2 insufflation pressure (15 mm of Hg) and operative time greater than 200 minutes. , Pneumothorax should be considered in the presence of hypercarbia, increased airway pressures, oxygen desaturation or any haemodynamic compromise.  A careful monitoring of EtCO2 , arterial oxygen saturation, airway pressures, pulse rate, blood pressure, ECG and inflation pressure along with close clinical scrutiny can lead to an immediate recognition of this complication, early treatment and uneventful recovery of the patient.
|1||Woolner DE, Johnson DM. Bilateral pneumothorax and surgical emphysema associated with laparoscopic cholecystectomy. Anaesthesia and Intensive care 1993 ; 21: 108-110.|
|2||Murdock CM, Wolff AJ, Geem TV. Risk factors for hypercarbia, subcutaneous emphysema, pneumothorax and pneumomediastinum during laparoscopy. Obstetrics and Gynecology 2000; 95: 704-709.|
|3||Prystowsky JB, Jericho BG, Epstein HM. Spontaneous bilateral pneumothorax - complication of laparoscopic cholecystectomy. Surgery 1993; 114: 988-92.|
|4||Joris JL. Anaesthesia for laparoscopic surgery. In: Miller RD editor: Anesthesia. New York: Churchill Livingstone 2005. p. 2285-2306.|
|5||Chui PT, Gin J, Chung SCS. Subcutaneous emphysema, pneumomediastinum and pneumothorax complicating laparoscopic vagotomy. Anaesthesia 1993; 48: 978-81.|
|6||Perko G, Fernandes A. Subcutaneous emphysema and pneumothorax during laparoscopy for ectopic pregnancy removal. Acta Anaesthesiol Scand 1997; 41:792-794.|
|7||Joris JL, Chiche J, Lamy ML. Pneumothorax during laparoscopic fundoplication: diagnosis and treatment with positive end expiratory pressure. Anesth Analg 1995; 81: 993-1000.|
|8||Ferzli GS, Kiel T, Hurwitz JB, et al. Pneumothorax as a complication of laproscopic inguinal hernia repair. Surg Endosc 1997; 11: 152-154.|