Effect of Intraoperative Ventilation Strategies on Postoperative Pulmonary Complications: A Meta-Analysis

Introduction: The role of intraoperative ventilation strategies in subjects undergoing surgery is still contested. This meta-analysis study was performed to assess the relationship between the low tidal volumes strategy and conventional mechanical ventilation in subjects undergoing surgery.Methods: A systematic literature search up to December 2020 was performed in OVID, Embase, Cochrane Library, PubMed, and Google scholar, and 28 studies including 11,846 subjects undergoing surgery at baseline and reporting a total of 2,638 receiving the low tidal volumes strategy and 3,632 receiving conventional mechanical ventilation, were found recording relationships between low tidal volumes strategy and conventional mechanical ventilation in subjects undergoing surgery. Odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CIs) were calculated between the low tidal volumes strategy vs. conventional mechanical ventilation using dichotomous and continuous methods with a random or fixed-effect model.Results: The low tidal volumes strategy during surgery was significantly related to a lower rate of postoperative pulmonary complications (OR, 0.60; 95% CI, 0.44–0.83, p < 0.001), aspiration pneumonitis (OR, 0.63; 95% CI, 0.46–0.86, p < 0.001), and pleural effusion (OR, 0.72; 95% CI, 0.56–0.92, p < 0.001) compared to conventional mechanical ventilation. However, the low tidal volumes strategy during surgery was not significantly correlated with length of hospital stay (MD, −0.48; 95% CI, −0.99–0.02, p = 0.06), short-term mortality (OR, 0.88; 95% CI, 0.70–1.10, p = 0.25), atelectasis (OR, 0.76; 95% CI, 0.57–1.01, p = 0.06), acute respiratory distress (OR, 1.06; 95% CI, 0.67–1.66, p = 0.81), pneumothorax (OR, 1.37; 95% CI, 0.88–2.15, p = 0.17), pulmonary edema (OR, 0.70; 95% CI, 0.38–1.26, p = 0.23), and pulmonary embolism (OR, 0.65; 95% CI, 0.26–1.60, p = 0.35) compared to conventional mechanical ventilation.Conclusions: The low tidal volumes strategy during surgery may have an independent relationship with lower postoperative pulmonary complications, aspiration pneumonitis, and pleural effusion compared to conventional mechanical ventilation. This relationship encouraged us to recommend the low tidal volumes strategy during surgery to avoid any possible complications.

Mallory–Weiss syndrome complicated by severe aspiration pneumonitis in an infant

ABSTRACT A 1-month-old girl presented with hematemesis and dyspnea. A large amount of blood was aspirated through a nasogastric tube, and chest computed tomography showed bilateral centrilobular opacified lesions, which suggested aspiration pneumonitis due to upper gastrointestinal bleeding. Her respiratory condition exacerbated, and we initiated nitric oxide (NO) therapy. Bleeding stopped with conservative treatment. She was weaned off mechanical ventilation and extubated on Day 6 after admission. Afterward, upper gastrointestinal endoscopy showed a longitudinal linear scar indicative of Mallory–Weiss syndrome (MWS). MWS is rarely reported in early infancy since many of the risk factors are absent in infants. Patients with aspiration pneumonitis usually recover respiratory function within 24 h and severe respiratory failure is rare in aspiration pneumonitis. There are no pediatric case reports describing MWS with severe aspiration pneumonitis. Although MWS is a rare cause of neonatal hematemesis, patients can become severely ill and require multidisciplinary treatment.

COMPARATIVE STUDY OF METOCLOPRAMIDE AND ONDANSETRON WITH PANTOPRAZOLE IN ELECTIVE CAESEREAN SECTION UNDER SPINAL ANAESTHESIA FOR ASPIRATION PNEUMONITIS PROPHYLAXIS.

BACKGROUND- Caesarean delivery, one of the most commonly performed surgical procedure. The choice of anaesthesia is spinal blockade for elective caeserean-section,unless general anaesthesia is specically indicated. Aspiration pneumonitis remains an important cause of morbidity and mortality in anaesthesia practise,particularly in obstetric patients,prophylaxis against it is paramount importance in pre-anaesthetic management. AIMS AND OBJECTIVES- The aim of this study was to compare pH and volume of gastric contents after administration of combination of metoclopramide and pantoprazole versus ondansetron and pantoprazole during elective caesarean section under spinal anaesthesia for prophylaxis against aspiration pneumonitis. METHODS: It is a prospective study where 100 parturient women, ASA 1 and 2 scheduled for elective caesarean section. They were divided into 2 groups: ondansetron(4mg) and pantoprazole(40mg),and metoclopramide(10mg), pantoprazole(40mg) administered intravenously 2hours before surgery. Gastric aspirate was taken in various positions before giving spinal anaesthesia and at the end of operation. Patients at risk were according to criteria of gastric volume more than 0.4ml/kg with pH <2.5. RESULTS:Patients at risk were 7(14%) in metoclopramide group and 1(2%) in ondansetron group before giving spinal anaesthesia(p=0.027) and 6(12%) in metoclopramide group and 0(0%) in ondansetron group at end of operation(p=0.012) . Since p-value was less than 0.05 there was signicant difference between two groups. CONCLUSION: As there was signicant difference between ondansetron and metoclopramide , it is recommended to use ondansetron and pantoprazole for prophylaxis against aspiration pneumonitis.

An uncommon etiological factor for aspiration pneumonitis caused by spontaneous sphenoid sinus meningoencephalocele with cerebrospinal fluid rhinorrhea: a case report

Background Aspiration pneumonitis is an inflammatory disease of the lungs which is difficult to diagnose accurately. Large-volume aspiration of oropharyngeal or gastric contents is essential for the development of aspiration pneumonitis. The role of cerebrospinal fluid (CSF) rhinorrhea is often underestimated as a rare etiological factor for aspiration in the diagnosis process of aspiration pneumonitis. Case presentation We present a case of a patient with 4 weeks of right-sided watery rhinorrhea accompanied by intermittent postnasal drip and dry cough as the main symptoms. Combined with clinical symptoms, imaging examination of the sinuses, and laboratory examination of nasal secretions, she was initially diagnosed as spontaneous sphenoid sinus meningoencephalocele with CSF rhinorrhea, and intraoperative endoscopic findings and postoperative pathology also confirmed this diagnosis. Her chest computed tomography showed multiple flocculent ground glass density shadows in both lungs on admission. The patient underwent endoscopic resection of meningoencephalocele and repair of skull base defect after she was ruled out of viral pneumonitis. Symptoms of rhinorrhea and dry cough disappeared, and pneumonitis was improved 1 week after surgery and cured 2 months after surgery. Persistent CSF rhinorrhea caused by spontaneous sphenoid sinus meningoencephalocele was eventually found to be a major etiology for aspiration pneumonitis although the absence of typical symptoms and well-defined risk factors for aspiration, such as dysphagia, impaired cough reflex and reflux diseases. Conclusions We report a rare case of aspiration pneumonitis caused by spontaneous sphenoid sinus meningoencephalocele with CSF rhinorrhea, which can bring more attention and understanding to the uncommon etiology for aspiration, so as to make more accurate diagnosis of the disease and early surgical treatment.

Aspiration Pneumonitis with Nasal Liquorrhea. Literature Review

Damage to the meninges in combination with the presence of a defect in the bone structures of the base of the skull and the formation of communication with the nasal cavity or paranasal sinuses are necessary conditions for nasal liquorrhea. There are a number of complications of nasal liquorrhea of various origins: infectious (meningitis, brain abscess), pneumocephalus, aspiration pneumonitis and gastritis. A review of the literature related to aspiration pneumonitis in nasal liquorrhea has been carried out. 4 articles were selected with descriptions of 9 cases. The analysis of demographic indicators of patients, clinical data, treatment characteristics was carried out. Based on the analysis of the literature, aspiration pneumonitis is a rare complication of nasal liquorrhea. For differential diagnosis with other types of pneumonitis, it is necessary to rely on additional clinical data, such as unilateral discharge of clear fluid from the nose when tilting the head, worsening of the condition and intensification of symptoms in a horizontal position, absence of systemic inflammatory response syndrome, ineffectiveness of antibiotic therapy, recurrent the nature of the flow. Antibiotic therapy does not cure the patient from pneumonitis. For the treatment of this pathology, it is first of all necessary to eliminate the cause of aspiration — to perform plastic surgery of the skull base defect in the absence of contraindications from the side of anesthetic aid.