Tension pneumoperitoneum in a child as complication of high frequency oscillatory ventilation: A case report

Mounika V Reddy; Arun Baranwal; Muralidharan Jayashree

doi:10.21304/2019.0606.00543

Users Online: 324

CASE REPORT

Year : 2019 | Volume : 6 | Issue : 6 | Page : 33-35

Tension pneumoperitoneum in a child as complication of high frequency oscillatory ventilation: A case report

Mounika V Reddy¹, Arun Baranwal², Muralidharan Jayashree²
¹ Senior Resident, Department of Pediatrics, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
² Professor, Department of Pediatrics, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India

Date of Submission	13-Sep-2019
Date of Acceptance	13-Nov-2019
Date of Web Publication	20-Dec-2019

Correspondence Address:
Arun Baranwal
Professor, Division of Pediatric Critical Care, Department of Pediatrics, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh 160012
India

Source of Support: None, Conflict of Interest: None

DOI: 10.21304/2019.0606.00543

Abstract

Pneumoperitoneum is most often secondary to a perforated hollow viscous mandating urgent surgical intervention. Pneumoperitoneum as a life-threatening complication of mechanical ventilation is rarely reported and presents a diagnostic and therapeutic challenge. Here, we report an 18-month old boy who developed tension pneumoperitoneum and abdominal compartment syndrome as complication of high frequency oscillatory ventilation, and was managed with percutaneous needle paracentesis. Awareness and thus early recognition of this rare complication of mechanical ventilation may help avoid needless laparotomy, and its associated morbidity.

Keywords: Mechanical ventilation, Barotrauma, Abdominal compartment syndrome, Laparotomy

How to cite this article:
Reddy MV, Baranwal A, Jayashree M. Tension pneumoperitoneum in a child as complication of high frequency oscillatory ventilation: A case report. J Pediatr Crit Care 2019;6:33-5

How to cite this URL:
Reddy MV, Baranwal A, Jayashree M. Tension pneumoperitoneum in a child as complication of high frequency oscillatory ventilation: A case report. J Pediatr Crit Care [serial online] 2019 [cited 2023 Apr 1];6:33-5. Available from: http://www.jpcc.org.in/text.asp?2019/6/6/33/279474

Introduction

Pneumoperitoneum, the presence of free air in the peritoneal cavity, is most often secondary to a perforated hollow viscous mandating urgent surgical intervention. Though barotrauma is an anticipated complication of positive pressure mechanical ventilation, especially with high distending pressures and/or volumes, pneumoperitoneum as a complication of mechanical ventilation is uncommonly reported, and presents a diagnostic and therapeutic dilemma in critically ill patients. Most of these patients can be managed with conservative measures.

Case Report

An 18-month old boy presented to pediatric emergency room with alleged history of accidental diesel ingestion 4 hours prior (small amount but not quantified), followed by rapid breathing. He got intubated and hand-ventilated at presentation for hypoxic respiratory failure and encephalopathy. A diagnosis of chemical pneumonitis (secondary to diesel ingestion and aspiration) with acute respiratory distress syndrome (ARDS) (PaO₂/FiO₂ ratio, 90) was made. Subsequently, he was transferred to pediatric intensive care unit (PICU) for mechanical ventilation, where he needed high frequency oscillatory ventilation (HFOV) (Sensormedics 3100A, initial settings being mean airway pressure (MAP), 30cmH₂O; amplitude, 50; frequency, 8Hz; and FiO₂, 1.0) for failure of conventional ventilation to correct the hypoxemia. Oxygenation index (OI) was 24 at initiation. Next day, pulmonary interstitial emphysema (PIE) and a rim of pneumomediastinum were noted on chest roentgenogram. On day 5 of PICU stay, on MAP of 30cmH₂O, he developed bilateral pneumothorax with subcutaneous emphysema which was managed with bilateral intercostal tube drainage. On day 7, he developed acute abdominal distension with features of abdominal compartment syndrome (intra-abdominal pressure measured via urinary bladder catheter being 30 cm H₂O), including reduced urine output, new onset hemodynamic instability and worsening oxygenation (OI, 52). Clinical examination revealed a tense but tympanic abdomen with normal bowel sounds. Until then, he was tolerating nasogastric tube feeds and was passing normal stools. There were no features suggestive of peritonitis. Abdominal roentgenogram revealed pneumoperitoneum [Figure 1]. Urgent percutaneous needle paracentesis was done to relieve the massive tension pneumoperitoneum. The abdomen got decompressed with a gush of air. Subsequently, a glove drain was inserted for continuous drainage considering potential re-accumulation of air. Effluent from the drain was minimal and clear. Considering the clinical setting, abdominal hollow viscus perforation seemed unlikely and pneumoperitoneum was attributed to high pressure mechanical ventilation. Abdominal ultrasound did not reveal any evidence of gut perforation. Hence, no surgical exploration was done. Repeat roentgenograms showed gradual resorption of pneumoperitoneum over next two days allowing removal of glove drain. The patient finally succumbed to persistent hypoxemia due to unrelenting ARDS, refractory shock and progressive multi-organ failure on day 13 of PICU stay.

Discussion

Barotrauma is an anticipated complication of positive pressure mechanical ventilation, especially in heterogeneous ARDS lung requiring high distending pressures and/or volumes. Extra-alveolar air may manifest in various combinations of PIE, pneumomediastinum, pneumothorax, subcutaneous emphysema or pneumoperitoneum. Rupture of alveoli with subsequent passage of the air into adjacent perivascular sheath initially results in PIE. Subsequently, air may dissect in any direction along tissue planes and lines of least resistance, resulting in aforesaid manifestations.^[1] Often, radiographic evidence of PIE or pneumomediastinum may be noted before the clinically evident manifestations.

Pneumoperitoneum is a less common, and probably an under-reported complication of mechanical ventilation.^[2] Several mechanisms have been postulated including passage of air along one of the mediastinal structures traversing diaphragm, via retroperitoneum or via microscopic diaphragmatic defects. Pneumoperitoneum, as an isolated complication of mechanical ventilation is rare. It is usually preceded by pneumomediastinum or pneumothorax ^[1],[3] as in the index patient. Pneumothorax doesn’t always result in pneumoperitoneum as intra-abdominal pressure exceeds intra-thoracic pressure in both inspiration and expiration. Adequate treatment of pneumothorax by tube thoracostomy may prevent development of pneumoperitoneum. The risk of pneumoperitoneum during mechanical ventilation increases with increasing distending pressures and volumes used. Mechanical ventilation induced pneumoperitoneum may be benign and asymptomatic, or it may be massive causing features of acute abdominal compartment syndrome with further respiratory compromise, hemodynamic instability and oliguria as seen in the index patient.

In a critical care setting, it is important to distinguish pneumoperitoneum secondary to mechanical ventilation from the one secondary to more sinister causes like gut perforation to avoid unwarranted exploratory laparotomy. Simultaneous presence of other air leaks points towards barotrauma while features of peritonitis or sepsis favor possibility of gut perforation.^[4],[5] However, use of steroids, immunosuppressive drugs, and sedoanalgesia may obscure clinical signs of perforation peritonitis in critically ill patients. In case of diagnostic dilemma, needle paracentesis, peritoneal lavage or contrast studies with water soluble radio-opaque contrast may be performed. Presence of intra-peritoneal fluid or extravasation of contrast points towards gut perforation. Literature review revealed two published reports of pneumoperitoneum secondary to high frequency oscillatory ventilation in children. Patel et al.^[6] reported a four-month baby with bronchiolitis with asymptomatic pneumoperitoneum which was managed conservatively. Another 18-month old boy with pneumonia who had tension pneumoperitoneum with abdominal compartment syndrome underwent bedside surgical exploration with no evidence of perforated viscus.^[7]

After having identified pneumoperitoneum, asymptomatic patients should be managed conservatively with close monitoring, serial abdominal examination, nil per oral, continuous gastric aspiration, adequate hydration and parenteral nutrition. Such an approach may avoid unnecessary invasive interventions like needle paracentesis and laparotomy, and their associated morbidity in critically ill patients. However, symptomatic patients with abdominal compartment syndrome may need continuous percutaneous drainage^[8] as was done in the index patient. Laparotomy should be avoided unless gut perforation is a strong clinical possibility.

Conclusion

Pneumoperitoneum is a life-threatening complication of mechanical ventilation and poses a diagnostic challenge to differentiate from surgical pneumoperitoneum. Conservative management suffices in most, however, percutaneous needle decompression may be considered in patients with abdominal compartment syndrome.

Source of Funding: Nil

Conflicts of interest: Nil

References

1.	Lellouche N, Bruneel F, Mignon F, Ayoub N, Troche G, Guezennec P, et al. Pneumomediastinum causing pneumoperitoneum during mechanical ventilation. J Crit Care. 2003;18:68-9.
2.	Henry RE, Ali N, Banks T, Dais KA, Gooray DA. Pneumoperitoneum associated with mechanical ventilation. J Natl Med Assoc. 1986;78:539-41.
3.	Okamoto A, Nakao A, Matsuda K, Yamada T, Osako T, Sakata H, et al. Non-surgical pneumoperitoneum associated with mechanical ventilation. Acute Medicine & Surgery. 2014;1:254-5.
4.	Mularski RA, Sippel JM, Osborne ML. Pneumoperitoneum: a review of nonsurgical causes. Crit Care Med. 2000;28:2638- 44.
5.	Williams NM, Watkin DF. Spontaneous pneumoperitoneum and other nonsurgical causes of intraperitoneal free gas. Postgrad Med J. 1997;73:531-6.
6.	Patel RV, Kumar H, Patwardhan N, Antao B. Pneumoperitoneum: a rare air leak in an infant with bronchiolitis and high-frequency oscillatory ventilation. BMJ Case Rep. 2013;2013.
7.	Hughes DB, Judge TN, Spigland NA. Tension pneumoperitoneum in a child resulting from high-frequency oscillatory ventilation: a case report and review of the literature. J Pediatr Surg. 2012;47:397-
8.	Karaman A, Demirbilek S, Akin M, Gurunluoglu K, Irsi C. Does pneumoperitoneum always require laparotomy? Report of six cases and review of the literature. Pediatr Surg Int. 2005;21:819-24.