Correlation between intra-abdominal pressure and pulmonary volumes after superior and inferior abdominal surgery

In Vitro Validation of a Novel Continuous Intra-Abdominal Pressure Measurement System (TraumaGuard)

Introduction: Intra-abdominal pressure (IAP) has been recognized as an important vital sign in critically ill patients. Due to the high prevalence and incidence of intra-abdominal hypertension in surgical (trauma, burns, cardiac) and medical (sepsis, liver cirrhosis, acute kidney injury) patients, continuous IAP (CIAP) monitoring has been proposed. This research was aimed at validating a new CIAP monitoring device, the TraumaGuard from Sentinel Medical Technologies, against the gold standard (height of a water column) in an in vitro setting and performing a comparative analysis among different CIAP measurement technologies (including two intra-gastric and two intra-bladder measurement devices). A technical and clinical guideline addressing the strengths and weaknesses of each device is provided as well. Methods: Five different CIAP measurement devices (two intra-gastric and three intra-vesical), including the former CiMON, Spiegelberg, Serenno, TraumaGuard, and Accuryn, were validated against the gold standard water column pressure in a bench-top abdominal phantom. The impacts of body temperature and bladder fill volume (for the intra-vesical methods) were evaluated for each system. Subsequently, 48 h of continuous monitoring (n = 2880) on top of intermittent IAP (n = 300) readings were captured for each device. Using Pearson's and Lin's correlations, concordance, and Bland and Altman analyses, the accuracy, precision, percentage error, correlation and concordance coefficients, bias, and limits of agreement were calculated for all the different devices. We also performed error grid analysis on the CIAP measurements to provide an overview of the involved risk level due to wrong IAP measurements and calculated the area under the curve and time above a certain IAP threshold. Lastly, the robustness of each system in tracking the dynamic variations of the raw IAP signal due to respirations and heartbeats was evaluated as well. Results: The TraumaGuard was the only technology able to measure the IAP with an empty artificial bladder. No important temperature dependency was observed for the investigated devices except for the Spiegelberg, which displayed higher IAP values when the temperature was increased, but this could be adjusted through recalibration. All the studied devices showed excellent ability for IAP monitoring, although the intra-vesical IAP measurements seem more reliable. In general, the TraumaGuard, Accuryn, and Serenno showed better accuracy compared to intra-gastric measurement devices. On average, biases of +0.71, +0.93, +0.29, +0.25, and -0.06 mm Hg were observed for the CiMON, Spiegelberg, Serenno, TraumaGuard, and Accuryn, respectively. All of the equipment showed percentage errors smaller than 25%. Regarding the correlation and concordance coefficients, the Serenno and TraumaGuard showed the best results (R2 = 0.98, p = 0.001, concordance coefficient of 99.5%). Error grid analysis based on the Abdominal Compartment Society guidelines showed a very low associated risk level of inappropriate treatment strategies due to erroneous IAP measurements. Regarding the dynamic tracings of the raw IAP signal, all the systems can track respiratory variations and derived parameters; however, the CiMON was slightly superior compared to the other technologies. Conclusions: According to the research guidelines of the Abdominal Compartment Society (WSACS), this in vitro study shows that the TraumaGuard can be used interchangeably with the gold standard for measuring continuous IAP, even in an empty artificial bladder. Confirmation studies with the TraumaGuard in animals and humans are warranted to further validate these findings.

Pilot Study on the Influence of Incentive Spirometry on Percutaneous Image-Guided Intra-Abdominal Drainage Catheter Pressure: A Potential Method to Enhance Drainage

Background

To report the evaluation of incentive spirometry (IS)-induced pressure changes in intra-abdominal drainage catheters and consider its use for maintaining catheter patency and enhancing drainage.

Methods

Prospective study of patients with indwelling intra-abdominal drainage catheters for abdominal fluid collections who had their intra-abdominal pressures measured while performing incentive spirometry. Patients were instructed in the use of an incentive spirometer. Within a week after initial drainage, pressure changes with IS were evaluated three times at 1500 cc and three times at maximum inspiratory effort. Intra-abdominal pressure (IAP) was measured using a pressure monitor connected to the drainage catheter.

Results

Twenty patients (men, 12; women, 8). Fluid collection locations were pelvis, Right-upper quadrant (RUQ), Left-upper quadrant (LUQ), Left-lower quadrant (LLQ), and Right-lower quadrant (RLQ). A total of 16 of 20 patients showed an elevation of IAP with IS. At 1500 cc, the pressure increased by an average of 41.24 mmH2O. At maximal inspiratory effort, the pressure increased by an average of 48.26 mmH2O. Pressure increase was greater in upper abdomen catheters. Four patients with lower abdominal and pelvic collections showed minimal pressure changes with IS.

Conclusion

IS increases IAP and fluid flow through abdominal drainage catheters. Future studies are warranted to determine whether the use of IS enhances catheter performance and facilitates drainage via its effect on IAP.

Post-operative pulmonary complications after thoracic and upper abdominal procedures at referral hospitals in Amhara region, Ethiopia: a multi-center study

Background

Thoraco-abdominal surgery cuts through muscle, disrupting the normal structure and function of the respiratory muscles, resulting in lower lung volumes and a higher risk of developing post-operative pulmonary complications (PPC). PPC remains an important cause of post-operative morbidity and mortality and impacts the long-term outcomes of patients after hospital discharge. This study was aimed at determining the incidence and factors associated with postoperative pulmonary complications among patients who underwent thoracic and upper abdominal surgery in the Amhara region of Ethiopia.

Methods

A multi-center follow-up study was conducted from April 1, 2022, to June 30, 2022, at comprehensive specialized hospitals in Amhara regional state, northwest Ethiopia. 424 patients were consecutively included in this study, with a response rate of 100%. A chart review and patient interview were used to collect data. A logistic regression analysis was performed to assess the strength of the association of independent variables with postoperative pulmonary complications.The crude odds ratio (COR) and adjusted odds ratio (AOR) with the corresponding 95% confidence interval were computed. Variables with a p-value of <0.05 were considered statistically significant predictors of the outcome variable.

Results

The incidence of postoperative pulmonary complication was 24.5%. Emergency procedures, preoperative SpO₂ < 94%, duration of surgery >2 h, patients with a nasogastric tube, intraoperative blood loss >500 ml and post-operative albumin <3.5 g/dl were factors associated with pulmonary complications. The most common complications were pneumonia (9.9%) followed by respiratory infection (4.2%).

Conclusion

The incidence of postoperative pulmonary complication after thoracic and upper abdominal surgery remains high. Preoperative SpO₂, duration of surgery, patients having a nasogastric tube, intraoperative blood loss and post-operative albumin were factors associated with post-operative pulmonary complications.

Volume Incentive Spirometry Reduces Pulmonary Complications in Patients After Open Abdominal Surgery: A Randomized Clinical Trial

Objective

To compare the effect of diaphragmatic breathing and volume incentive spirometry (VIS) on hemodynamics, pulmonary function, and blood gas in patients following open abdominal surgery under general anesthesia.

Methods

A total of 58 patients who received open abdominal surgery were randomly assigned to the control group (n=29) undergoing diaphragmatic breathing exercises and the VIS group (n=29) undergoing VIS exercises. All the participants performed the six-minute walk test (6MWT) preoperatively to evaluate their functional capacity. Hemodynamic indexes, pulmonary function tests, and blood gas indexes were recorded before surgery and on the 1st, 3rd, and 5th postoperative day.

Results

The functional capacity was not significantly different between the two groups during the preoperative period (P >0.05). At 3 days and 5 days postoperatively, patients in the VIS group had a significantly higher SpO2 than that in the control group (P <0.05). Pulmonary function test values were reduced in both two groups postoperatively when compared to the preoperative values but improved for three and five days afterward (P <0.05). Of note, the significantly elevated levels of peak expiratory flow (PEF), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio were observed on the 1st, 3rd, and 5th postoperative days in the VIS group compared with those in the control group (P <0.05). Besides, bass excess (BE), and pH values were significantly higher in the VIS group on the 1st postoperative day than those in the control group (P <0.05).

Conclusion

Diaphragmatic breathing and VIS could improve postoperative pulmonary function, but VIS exercise might be a better option for improving hemodynamics, pulmonary function, and blood gas for patients after open abdominal surgery, hence lowering the incidence of postoperative pulmonary complications.

Ultrasonographic Assessment of Diaphragmatic Inspiratory Amplitude and Its Association with Postoperative Pulmonary Complications in Upper Abdominal Surgery: A Prospective, Longitudinal, Observational Study

Background

Diaphragmatic dysfunction following upper abdominal surgery is less recognized due to a lack of diagnostic modality for bedside evaluation. We used point-of-care ultrasound to evaluate the diaphragmatic inspiratory amplitude (DIA) in upper abdominal surgery for cancer. Our primary hypothesis was DIA would be reduced in the immediate postoperative period in patients with postoperative pulmonary complications (PPCs). Our aim was to identify an optimal cutoff of DIA for the diagnosis of PPCs.

Methods

We conducted a prospective, observational study in patients aged 18-75 years undergoing elective, upper abdominal oncological surgeries under combined general and epidural anesthesia. Ultrasound evaluation of the diaphragm was done by measuring the DIA in the right and left hemidiaphragms during quiet and deep breathing on the day before surgery and postoperative days (PODs) 1, 2, and 3. Patients were followed up for PPCs until POD 7. The linear mixed-effects model examined the association between DIA and PPCs and other perioperative factors. Receiver-operating characteristics analysis was done to determine the optimal cutoff of DIA in diagnosing PPCs.

Results

DIA measured in the 162 patients showed a significant decrease in their absolute values postoperatively from its preoperative baseline measurement. This decrease in DIA was significantly associated with PPC [right hemidiaphragm, β = -0.17, 95% confidence interval (CI) -0.31 to -0.02, p = 0.001 during quiet breathing; left hemidiaphragm, β = -0.24, 95% CI = -0.44 to -0.04, p = 0.018 and β = -0.40, 95% CI = -0.71 to -0.09, p = 0.012 during quiet and deep breathing, respectively]. A cutoff value of DIA of left hemidiaphragm at 1.3 cm during quiet breathing and 1.6 cm during deep breathing had a sensitivity of 77 and 75%, respectively, in their ability to diagnose PPCs [left hemidiaphragm quiet breathing, area under the curve (AUC): 0.653, 95% CI 0.539-0.768, p = 0.015; left hemidiaphragm deep breathing, AUC: 0.675, 95% CI 0.577-0.773, p = 0.007].

Conclusion

Following upper abdominal surgery, the DIA is decreased and associated with PPCs. DIA of left hemidiaphragm less than 1.3 cm during quiet breathing and 1.6 cm during deep breathing has a sensitivity of 77 and 75%, respectively, in diagnosing PPCs following upper abdominal surgery.

How to cite this article

Vanamail PV, Balakrishnan K, Prahlad S, Chockalingam P, Dash R, Soundararajan DK. Ultrasonographic Assessment of Diaphragmatic Inspiratory Amplitude and Its Association with Postoperative Pulmonary Complications in Upper Abdominal Surgery: A Prospective, Longitudinal, Observational Study. Indian J Crit Care Med 2021;25(9):1031-1039.

Opioid use may be associated with postoperative complications in myotonic dystrophy type 1 with high-grade muscular impairment

Individuals with myotonic dystrophy type 1 (DM1) reportedly have a higher risk of postoperative complications than those without DM1; however, factors related to perioperative complications in DM1 patients remain unclear. We aimed to identify the risk factors that may be associated with postoperative complications in DM1 patients. We reviewed medical records of 256 patients with DM1 from 1998 to 2018, among whom 42 (16.4%) had previously undergone 51 surgeries under general and regional anaesthesia. Among the 42 patients, 11 (21.5%) had 13 postoperative complications including respiratory complications, sustained hypotension, wound infection and dehiscence, artery thrombosis and occlusion, and delayed recovery from anaesthesia. There were significant inter-group differences between the non-complicated and complicated groups considering the following parameters: high-grade (≥ 3) muscular impairment rating scale (MIRS), extubation time, postoperative opioid use, and hospital length of stay. Furthermore, univariate analysis revealed that an MIRS score ≥ 3 (odds ratio [OR] 9.346, confidence interval [CI] 1.761–49.595, p = 0.009) and postoperative opioid use (OR 8.000, CI 1.772–36.127, p = 0.007) were the only statistically significant factors. Therefore, clinicians should be cautious in administering opioids, particularly in patients with a high-grade MIRS score during the perioperative period.

Pulmonary function evaluation in type 2 diabetes mellitus patients submitted to metabolic surgery

Abstract Introduction: Diabetes Mellitus (DM) is a multifactorial metabolic disorder. As considered a public health problem needing additional treatment options. Objective: This prospective study aimed at evaluating pulmonary function through spirometry, before and after metabolic surgery without gastric resection in type 2 DM patients. Methods: Sample was composed by 17 type 2 DM females. They were analyzed in pre (24 hours before surgical procedure), immediate post-operative period POST1 (24 hours after surgical procedure) and in the late postoperative period POST2 (two years after surgical procedure). Besides statistical analysis, it was evaluated the following spirometric parameters: forced vital capacity (FVC), forced expiratory volume in the first second (FEV1) and the FEV1 / FVC ratio (%). Results: Spirometric parameters showed a value increase when compared PRE and POS2 values, except for FVC and FEV1, which was not statistically significant. Conclusion: Type 2 DM women submitted to metabolic surgery without gastric resection showed spirometric value increased after two-year surgical procedure, when compared to preoperative period values. It is important additional studies about pulmonary function, diabetic patients and metabolic surgery without gastric resection.

Is preoperative spirometry a predictive marker for postoperative complications after colorectal cancer surgery?

Background

Spirometry is a basic test that provides much information about pulmonary function; it is performed preoperatively in almost all patients undergoing colorectal cancer (CRC) surgery in our hospital. However, the value of spirometry as a preoperative test for CRC surgery remains unknown. The aim of this study was to determine whether spirometry is useful to predict postoperative complications (PCs) after CRC surgery.

Methods

The medical records of 1236 patients who had preoperative spirometry tests and underwent CRC surgery between 2005 and 2014 were reviewed. Preoperative spirometry results, such as forced vital capacity (FVC), one-second forced expiratory volume (FEV1), %VC (FVC/predicted VC) and FEV1/FVC (%FEV1), were analyzed with regard to PCs, including pneumonia.

Results

PCs were found in 383 (30.9%) patients, including 218 (56%) with surgical site infections, 67 (17%) with bowel obstruction, 62 (16%) with leakage and 20 (5.2%) with pneumonia. Of the spirometry results, %VC was correlated with PC according to logistic regression analysis (odds ratio, OR = 0.99, 95% confidence interval, CI = 0.98-0.99; P = 0.034). Multivariate analysis after adjusting for male sex, age, laparoscopic surgery, tumor location, operation time and blood loss showed that a lower %VC tends to be a risk factor for PC (OR = 0.99, 95% CI = 0.98-1.002; P = 0.159) and %VC was an independent risk factor for postoperative pneumonia in PCs (OR = 0.97, 95% CI = 0.94-0.99; P = 0.049).

Conclusions

In CRC surgery, %VC may be a predictor of postoperative complications, especially pneumonia.

Putative risk factors for postoperative pneumonia which affects poor prognosis in patients with gastric cancer

BACKGROUND AND OBJECTIVES

Several recent studies identified that postoperative infectious complications contribute to recurrence and poor outcome in patients with gastric cancer. This study was designed to investigate the prognostic impact of postoperative pneumonia, and to identify the putative risk factors for its occurrence.

METHODS

We retrospectively analyzed 1,415 consecutive patients who underwent curative gastrectomy for gastric cancer between 1997 and 2013.

RESULTS

A total of 31 (2.2 %) patients developed postoperative pneumonia (Clavien-Dindo classification ≥II). Patients with postoperative pneumonia showed a significantly poorer prognosis than patients without (P < 0.001). Concerning the occurrence of postoperative pneumonia, univariate and multivariate analyses identified older age (≥65 years; P = 0.010; odds ratio [OR] 3.59), lower nutritious status (albumin <3 0; P = 0.029; OR 4.51), advanced stage (pStage ≥II; P = 0.045; OR 2.35), concurrent hypertension (P = 0.042; OR 2.21) and total gastrectomy (P = 0.026; OR 2.42) as independent risk factors.

CONCLUSIONS

Postoperative pneumonia was shown to be associated with long-term poor outcome in patients with gastric cancer. Care should be taken for patients with clinical factors such as older age, lower nutritional status, advanced stage, concurrent hypertension, and total gastrectomy.