Two mechanically ventilated cases of COVID-19 successfully managed with a sequential ventilation weaning protocol: Two case reports.

BACKGROUND: Patients with critical coronavirus disease 2019 (COVID-19), characterized by respiratory failure requiring mechanical ventilation (MV), are at high risk of mortality. An effective and practical MV weaning protocol is needed for these fragile cases. CASE SUMMARY: Here, we present two critical COVID-19 patients who presented with fever, cough and fatigue. COVID-19 diagnosis was confirmed based on blood cell counts, chest computed tomography (CT) imaging, and nuclei acid test results. To address the patients' respiratory failure, they first received noninvasive ventilation (NIV). When their condition did not improve after 2 h of NIV, each patient was advanced to MV [tidal volume (Vt), 6 mL/kg ideal body weight (IBW); 8-10 cmH2O of positive end-expiratory pressure; respiratory rate, 20 breaths/min; and 40%-80% FiO2] with prone positioning for 12 h/day for the first 5 d of MV. Extensive infection control measures were conducted to minimize morbidity, and pharmacotherapy consisting of an antiviral, immune-enhancer, and thrombosis prophylactic was administered in both cases. Upon resolution of lung changes evidenced by CT, the patients were sequentially weaned using a weaning screening test, spontaneous breathing test, and airbag leak test. After withdrawal of MV, the patients were transitioned through NIV and high-flow nasal cannula oxygen support. Both patients recovered well. CONCLUSION: A MV protocol attentive to intubation/extubation timing, prone positioning early in MV, infection control, and sequential withdrawal of respiratory support, may be an effective regimen for patients with critical COVID-19.

COVID-19 managed with early non-invasive ventilation and a bundle pharmacotherapy: A case report.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has become an immense public health burden, first in China and subsequently worldwide. Developing effective control measures for COVID-19, especially measures that can halt the worsening of severe cases to a critical status is of urgent importance. CASE SUMMARY: A 52-year-old woman presented with a high fever (38.8 °C), chills, dizziness, and weakness. Epidemiologically, she had not been to Wuhan where COVID-19 emerged and did not have a family history of a disease cluster. A blood test yielded a white blood cell count of 4.41 × 109/L (60.6 ± 2.67% neutrophils and 30.4 ± 1.34% lymphocytes). Chest imaging revealed bilateral ground-glass lung changes. Based on a positive nasopharyngeal swab nucleic acid test result and clinical characteristics, the patient was diagnosed with COVID-19. Following treatment with early non-invasive ventilation and a bundle pharmacotherapy, she recovered with a good outcome. CONCLUSION: Early non-invasive ventilation with a bundle pharmacotherapy may be an effective treatment regimen for the broader population of patients with COVID-19.

[Effects of volume resuscitation on venous pressure gradient in hypovolemic patients undergoing mechanical ventilation].

OBJECTIVE: To investigate the value of venous pressure gradient [D(c-i)VP] between central venous pressure (CVP) and iliac vein pressure (IVP) in assessing the responsiveness to volume resuscitation in hypovolemic patient undergoing mechanical ventilation. METHODS: Thirty hypovolemic patients undergoing mechanical ventilation, with maintenance of similar ventilation conditions, graded volume loading was performed with 250 ml Ringer lactate solution (LR) for each infusion in hypovolemic patients, until mean arterial pressure (MAP) ≥65 mm Hg(1 mm Hg = 0.133 kPa), CVP≥8 mm Hg, strong pulse, perfusion improvement (recovery in the end) were reached. Before infusion, 10 minutes after infusion, and at the end of recovery, the heart rate (HR), MAP, CVP, IVP, stroke volume (SV), thoracic fluid content (TFC) and D(c-i)VP were measured and recorded, the correlations between D(c-i)VP and TFC, SV before and after infusion were analyzed. RESULTS: Before infusion, 10 minutes after infusion, and at the end of recovery, no significant difference was found in HR, MAP, CVP, and IVP,while D(c-i)VP (mm Hg) was obviously lowered (4.89 ± 1.70, 2.80 ± 1.44, 2.10 ± 1.30, respectively), and SV (ml) and TFC (ml) were significantly increased (SV was 42.0 ± 10.5, 49.0 ± 8.3, 58.0 ± 12.1, respectively; TFC was 30.0 ± 9.6, 38.0 ± 8.6, 43.0 ± 11.1, respectively), with statistical differences (P < 0.05 or P < 0.01). Negative correlations were found between D(c-i)VP and TFC, SV [r(1)=-0.580, P(1)=0.004; r(2)=-0.462, P(2) =0.017]. CONCLUSIONS: In the course of fluid resuscitation in hypovolemic patients undergoing mechanical ventilation, the D(c-i)VP was significantly reduced with fluid resuscitation. At the same time, significant correlations between D(c-i)VP, TFC and SV were demonstrated. The measurement of D(c-i)VP could help guide fluid resuscitation in hypovolemic patients undergoing mechanical ventilation.

[Effect of positive end-expiratory pressure on the pressure gradient of venous return in hypovolemic patients under mechanical ventilation].

OBJECTIVE: To assess the effects of positive end-expiratory pressure (PEEP) on central venous pressure (CVP) and common iliac venous pressure (CIVP), and the difference between CVP and CIVP [D(c-i)VP] in hypovolemic patients under mechanical ventilation. METHODS: From May 2007 to May 2009, 30 acute hypovolemic adult patients undergoing mechanical ventilation in intensive care unit (ICU) were enrolled. The patients were randomly divided into three groups, and PEEP with 0, 5, 10 cm H(2)O (1 cm H(2)O=0.098 kPa) levels were used respectively. Ten mechanically ventilated patients with similar basic clinical conditions but normal blood volume were selected randomly as the control group. CVP, CIVP and D(c-i)VP were measured and recorded at each PEEP level in both groups. The patients' heart rate, mean artery pressure and respiratory pressure data were also collected. The correlation analysis was used to analyze relationship between CVP and CIVP and between the changes in venous pressure and the changes in respiratory pressure. RESULTS: (1)CVP increased significantly when PEEP level was elevated in the study group. When PEEP was 0, 5 and 10 cm H(2)O, the CVP was (1.3+/-0.9), (3.1+/-1.3) and (4.5+/-1.3) mm Hg, respectively (1 mm Hg=0.133 kPa, all P<0.01). Whereas, in the control group, the changes in CVP was small. At 0, 5 and 10 cm H(2)O PEEP levels, CVP was (6.9+/-1.3), (7.2+/-1.2) and (8.0+/-1.5) mm Hg, respectively, but when CVP at PEEP0 and PEEP5 was compared with that of PEEP10, the difference was significant (P<0.01 and P<0.05). There was slight increase of CIVP in both groups when PEEP was elevated. D(c-i)VP was increased significantly in the study group compared with control group (all P<0.01). But the value was gradually decreased when with elevation of PEEP. When PEEP level was elevated from 0 to 10 cm H(2)O, D(c-i)VP value was lowered from (4.9+/-1.7) mm Hg to (2.8+/-1.4) mm Hg. No significant difference in D(c-i)VP was found in the control group. The D(c-i)VP values in the control group were equal or lower than 1.5 mm Hg at three PEEP levels. (2)No relationship was found between CVP and CIVP at each PEEP level in the study group (r(1)=0.236, r(2)=0.299, r(3)=0.262, all P>0.05), but there was a statistically significant correlation between CVP and CIVP in the control group (r(1)=0.485, r(2)=0.679, r(3)=0.748, all P<0.05). CONCLUSION: The findings suggest that it may not be appropriate to use CVP or CIVP to evaluate the patients' blood volume and effect of volume resuscitation in the hypovolemic patients undergoing mechanical ventilation in combination with PEEP.

[Effect of positive end-expiratory pressure on central venous pressure and common iliac venous pressure in mechanically ventilated patients].

OBJECTIVE: To evaluate the effects of positive end-expiratory pressure (PEEP) on central venous pressure (CVP) and common iliac venous pressure (CIVP), the relationship between CVP and CIVP, in order to analyze the correlation between CVP or CIVP and airway pressure in patients during mechanical ventilation. METHODS: Twenty mechanically ventilated adult patients with steady circulatory state and without cardiopulmonary ailment, abdominal distention or coagulopathy were enrolled for the study from February to August in 2007. 0, 5, 10 cm H(2)O (1 cm H(2)O=0.098 kPa) PEEP was used randomly in all cases during mechanical ventilation. CVP, CIVP, the gradient between CVP and CIVP at each PEEP level were measured. Linear correlation and linear regression analysis were used to analyze relative changes between CVP and CIVP. The data of airway pressure in the patients with mechanical ventilation were obtained for evaluating their correlation with CVP or CIVP. RESULTS: CVP and CIVP increased as PEEP was elevated (P<0.05 or P<0.01). There was a significant linear correlation between CVP and CIVP at 0, 5, 10 cm H(2)O PEEP level (r was 0.620, 0.658 and 0.777, respectively, P<0.01). The linear regression equation was Y (CVP)=0.402+0.732X (CIVP). The mean difference between CVP and CIVP at 0, 5, 10 cm H(2)O PEEP level was (1.9+/-1.7), (2.3+/-1.3), and (1.9+/-1.1) mm Hg (1 mm Hg=0.133 kPa, respectively P>0.05). There was a positive correlation between CVP or CIVP and the airway pressure, but only mean airway pressure and PEEP showed significant linear correlation with CVP (r was 0.634, 0.603, respectively, P<0.01) and CIVP (r was 0.751, 0.685, respectively, P<0.01). No obvious change was found in mean arterial pressure, heart rate, and expiratory tidal volume during the study. CONCLUSION: CVP and CIVP increased when PEEP is set