The Utility of Open Lung Biopsy in Patients Requiring Mechanical Ventilation: Materials and Methods
The information obtained included the following: demographic data, data taken before (Table 1) and after (Table 2) open lung biopsy, open lung biopsy histological diagnosis, open lung biopsy-initiated treatment changes and resultant outcome, cause of death, and hospital outcome.
The extent of organ failure, other than respiratory, at the time leading up to open lung biopsy was determined based on previously established criteria defined in Table 3.
Immunosuppression was defined as a blood white-cell count of < 500/mm or the use of steroids for longer than 7 days.
The open lung biopsies were performed in an operating theater under general anesthesia. Access to the lung was via an anterior mini-thoracotomy. Sampling sites were selected based on radiologically affected sites and/or the lingula. A maximum of two tissue samples were obtained. All patients had one or two underwater seal drains in situ postoperatively. All operative lung samples were sent for Gram’s staining and bacteriological, viro-logical, and histological analysis Source canadian health mall. Sampling sites were not used as a variable for analysis, because those sites sampled had been well documented in terms of their efficacy.
Statistical analysis of the data was carried out using descriptive statistics for the ratio data and the x2 test for nominal data and non-normally distributed data. Mean, SD, and 95% confidence intervals (CIs) were determined. Analysis was performed by the computerized statistical software package Minitab v 8 (Minitab Inc; Philadelphia, PA).
Open lung biopsy was an infrequently performed procedure with a yearly incidence of 0 to 0.9% of patient admissions to the ICU. Twenty-four patients were identified who fulfilled the study criteria. The mean age (± SD) was 48.9 ± 16.1 years.
Table 1—Patient Demographics
|Age, yr||Gender||Admission Diagnosis||Before Open Lung Biopsy Fio2/Pao2||Before Open Lung Biopsy Ventilation||Other Organ Failure|
|63||F||Congestive cardiac failure||128||Yes||1|
|32||F||Metastatic breast carcinoma||180||No||1|
Table 2—Patient Characteristics for Survivors and Nonsurvivors
|Patient Characteristics||Survivors(n = 8)||Nonsurvivors (n = 16)||p Value|
|Age, yr||48.5 (± 17)*||49.1 (± 16.2)*||0.94|
|Pa02/Fi0£ before open lung biopsy||158 (95% CI, 119-199)||145 (95% CI, 118-172)||0.53|
|Ventilation before open lung biopsy||50%||63%||0.56|
|Median number of other organ failure||1||2||0.05|
|Pa02/Fi02 differences before/after open lung biopsy||-3 (95% CI, -27-21)||-14 (95% CI, 42-14)||0.52|
|Complications during open lung biopsy||25%||7%||0.19|
|Complications after open lung biopsy||25%||13%||0.44|
|Open lung biopsy histology|
|Specific or normal||63%||44%||0.40|
|Open lung biopsy-initiated treatment change||88%||63%||0.20|
Table 3—Multiple Organ Dysfunction Criteria
|Respiratory||Pao/Fio2 < 250|
|Positive end-expiratory pressure > 5 cmh2o|
|Need for mechanical ventilation|
|Cardiovascular||MAP < 80 mm Hg|
|Inotropic drugs required to maintain MAP> 80 mm Hg|
|Cardiac index < 2.0 L/m2|
|Hepatic||Total bilirubin > 60 mmol/L (in the absence of hemolysis)|
|International normalized ratio > 1.6|
|Hematological||Platelets < 50,000/mm|
|Leukocytes < 500/mm|
|Hemoglobin < 10 g/dL (and/or requiring transfusion to support this level in the absence of blood loss)|
|Evidence of disseminated intravascular coagulation (fibrinogen < 1 g/L and elevated D-dimer levels)|
|Neurological||Glasgow Coma Scale < 8 in the absence of sedative drugs|
|Renal||Serum creatinine > 240 mmol/L|
|Need for dialysis or ultrafiltration|