Maximum Intra-abdominal Pressure Research Articles

Subcutaneous emphysema associated with laparoscopic or robotic abdominal surgery: a retrospective single-center study.

Subcutaneous emphysema (SCE) is a common complication in laparoscopic surgery. However, its precise incidence and impact on the clinical course are partially known. In this study, the incidence and risk factors of SCE were retrospectively analyzed. Patients who underwent laparoscopic/robotic abdominal surgery (e.g., gastrointestinal, hepatobiliary, gynecologic, and urologic surgery) between October 2019 and September 2022 were retrospectively analyzed. The presence of SCE was confirmed by either conclusive findings obtained through chest/abdominal X-ray examination immediately after operation, or intraoperative palpation conducted by nurses. X-ray examination was performed in the operation room before extubation. A total of 2503 patients treated with laparoscopic/robotic abdominal surgery between October 2019 and September 2022 were identified and all of them were included in the analysis. SCE was confirmed in 23.1% of the patients (i.e., 577/2503). SCE was identified by X-ray examination in 97.6% of the patients. Extubation failure was observed in 10 patients; however, pneumothorax was not observed. Female sex (odds ratio [OR]: 2.09; 95% confidence interval [95%CI]: 1.69-2.57), age ≥ 80years (OR 1.63; 95%CI 1.19-2.22), body mass index < 20 (OR 1.32; 95%CI 1.06-1.65), operation time > 360min (OR 1.97; 95%CI 1.53-2.54), robotic surgery (OR 2.54; 95%CI 1.91-3.38), maximum intraabdominal pressure with CO2 > 15mmHg (OR 1.79; 95%CI 1.02-3.16), and endo-tidal CO2 > 50mmHg (OR 1.32; 95%CI 1.08-1.62)were identified as independent factors of SCE. Regarding the extubation failure due to SCE, age (OR 5.84; 95%CI 1.27-26.8) and maximum intraabdominal pressure with CO2 (OR 21.7; 95%CI 4.76-99.3) were identified as risk factors. Although the presence of SCE is associated with a low risk of severe complications, monitoring of the perioperative intraabdominal pressure is essential for performing safe laparoscopic/robotic surgery, particularly in elderly patients.

Moderate Intra-Abdominal Pressure Levels in Robot-Assisted Radical Prostatectomy Seem to Have No Negative Impact on Clinical Outcomes.

Introduction: Radical prostatectomy is increasingly performed laparoscopically with robot assistance (RALRP). RALRP, as with all laparoscopic procedures, requires a pneumoperitoneum, which might result in peritoneal inflammatory response reactions and postoperative pain. The aim of this retrospective single-centre study was to analyse the effects of a pneumoperitoneum during RARLP on clinical outcomes. Methods: All patients who underwent robot-guided prostatectomy in our clinic were included, with the exception of patients who were converted to open prostatectomy. C-reactive protein was used as a marker for the primary outcome, namely the postoperative inflammatory response. Intra-abdominal pressure (IAP) was evaluated as a potential factor influencing inflammation. In addition, the waist-hip ratio was used to estimate the amount of visceral adipose tissue, and the administration of dexamethasone was considered as a factor influencing inflammation. The Visual Analogue Scale (VAS) was used to determine postoperative pain. Patients were consecutively recruited between 1 September 2020 and 31 March 2022. Results: A total of 135 consecutive patients were included. The median waist-hip ratio was 0.55. The median duration of the pneumoperitoneum was 143 min. The median values of the average and maximum IAP values were 10 mmHg and 15 mmHg, respectively. The mean CRP of the first postoperative day was 6.2 mg/dL. The median VAS pain level decreased from 2 to 1 from the first to the third postoperative day. On the first postoperative day, 16 patients complained of shoulder pain. In addition, 134 patients were given some form of opioid pain treatment following surgery. Conclusion: We could not identify any relevant associations between the duration and IAP of the pneumoperitoneum and the indirect markers of inflammation or indicators of pain, or between the latter and the amount of visceral adipose tissue. In addition, we found no significant effect of the administration of dexamethasone on postoperative inflammation. The results point to a noninferior tolerability of moderate pressure during the procedure compared to the commonly utilised higher pressure, yet this must be confirmed in randomised controlled trials.

ASSESSMENT OF INTRA-ABDOMINAL HYPERTENSION AND ITS CORRELATION TO ORGAN FAILURE IN PATIENTS ADMITTED TO SURGICAL CRITICAL CARE UNIT

Background: Intra-abdominal hypertension (IAH) is the sustained elevation in intra-abdominal pressure (IAP) ≥ 12 mmHg. It has been shown to affect various organs of the body, causing derangement and dysfunction of different organ systems. However the problem remains unappreciated and this study was done to assess the problem of IAH among the ICU patients in our own environment and also to understand the signicance of elevated IAPas a marker of organ dysfunction. Objectives Ÿ To assess prevalence of intra-abdominal hypertension in a surgical critical care unit of a tertiary care hospital Ÿ To correlate intra-abdominal hypertension with organ failure in patients admitted to surgical critical care unit. Methodology: This was an observational prospective study done among 75 patients who were admitted for a minimum period of 3 consecutive days in the surgical critical care unit of JMMC&amp;RI, Thrissur from April 2016 to March 2017. The IAP was measured thrice daily, and SOFAscore daily for 3 consecutive days. The results were analyzed using SPSS software. Results: The prevalence of IAH in patients admitted to surgical critical care unit is 46.7% based on mean IAPand 78.7% based on maximum IAP. The mean IAPand SOFAscore were 11.40 ± 4.37 mmHg and 4.55 ± 2.72 respectively. 34.7 % of patients had organ failure. 51.4% of patients with IAH had organ failure. The mortality was 22.9% in population with IAH. The mean ICU stay and hospital stay in patients with IAH were 6.77 ± 4.98 and 13.37 ± 8.09 days respectively Conclusion:The prevalence of IAH in patients admitted to surgical critical care unit is 46.7%. There is a signicantly higher incidence of organ failure, longer ICU stay and hospital stay in patients with IAH. No signicant association was found between IAH and mortality.

The prevalence, incidence and mortality associated with intra-abdominal hypertension among patients in intensive care units of a low-income country: a cohort study

Background: Intra-abdominal hypertension (IAH) is sustained increase in intra-abdominal pressure (IAP) ≥12 mmHg in adults and ≥10 mmHg in children. IAH has been noted to be associated with increased morbidity and mortality among critically ill patients. Measurement of IAP is common among at risk patients in the developed world. However, it has not received due attention in the majority of intensive care units (ICUs) in low-income countries, Uganda being one of these. This is evidenced by paucity of data and lack of protocols from the Ugandan Ministry of Health. This multi-center study was thus conducted to assess the prevalence, incidence and mortality associated with IAH among patients admitted to Ugandan ICUs.Methods:A multi-center prospective cohort study was conducted from September 2017 to February 2018 at three ICUs in Uganda. We consecutively enrolled 126 patients into the study. IAP was measured using the Harrahil manometer technique. Categorical variables were analyzed using the Chi square test and continuous variables analyzed using the t-test and Man Whitney test. The prevalence and incidence were determined using proportions and mortality was determined using survival analysis.Results:The median age was 33 years (26-48.5) for the patients without IAH and 42 years (29-55) for those with IAH. The majority of the patients were male and 9.6% of the patients were below 18 years. The prevalence of IAH was 62.7 (CI 54.1-71.3), whereas the 24 hour and 72 hour incidence of IAH was 9.3% (CI 1.3-17.2) and 14.3 % (CI 4.1-24.4), respectively. Mortality was higher in patients with IAH compared to those without (p-value 0.003 and 0.028, mean and maximum IAP, respectively). Conclusion:We found a high prevalence and incidence of IAH among critically ill patients, associated with a high mortality. Routine screening for IAH can preempt management strategies to mitigate this.

Intra-Abdominal Pressure, a Prognostic Marker in the Evolution of Acute Pancreatitis

AbstractIn acute pancreatitis some prognostic scores have been suggested, based on clinical, laboratory and radiological criteria. The most popular are: Ranson score, APACHE II score and CT severity index (CTSI). The trend is to find a prognostic marker that is easy to use, cheap, and reproductible. Recently, the increase of the intra-abdominal pressure (IAP) has drawn attention. Material and Methods: From January 2012 to April 2014, a group of 64 patients, admitted to the Clinical Department of Anaesthesia and Intensive Care and the Surgical Departments of the SCJU Sibiu, with the diagnosis of acute pancreatitis, were included in this observational prospective study. The cut-off values, the specificity and sensitivity of the prognostic scores were calculated using the receiver operating characteristics (ROC) analysis curves. Results: At a cut-off value of 12 mm Hg IAP max has a sensitivity of 0,75, similar to Ranson score at 48 h (0.72 at a cut-off value 3) and CTSI (0,73 at a cut-off value 4). Better results are just for APACHE II score at 24 h (0,88 at a cut-off value 8). IAP max has a specificity of 0,88, simillary to CTSI (0,83) and APACHE II score (0,82). Conclusions: In our study maximum IAP could be correlated with prognostic markers for severe evolution in acute pancreatitis.

Clinical Effects of Intra-Abdominal Pressure in Critically Ill Trauma Patients

Purpose: There is increasing interest in intra-abdominal pressure (IAP) and intra-abdominal hypertension (IAH) in critically ill patients. This study investigated the effects and outcomes of elevated IAP in a trauma intensive care unit (ICU) population. Methods: Eleven consecutive critically ill patients admitted to the trauma ICU at Pusan National University Hospital Regional Trauma Center were included in this study. IAP was measured every 8-12 hours (intermittently) for 72 hours. IAP was registered as mean and maximal values per day throughout the study period. IAH was defined as IAP ≥12 mmHg. Abdominal compartment syndrome was defined as IAP ≥20 mmHg plus ≥1 new organ failure. The main outcome measure was in-hospital mortality. Results: According to maximal and mean IAP values, 10 (90.9%) of the patients developed IAH during the study period. The Sequential Organ Failure Assessment (SOFA) score was significantly higher in patients with IAP ≥20 mmHg than in those with IAP <20 mmHg (16 vs. 5, p=0.049). The hospital mortality rate was 27.3%. Patients with a maximum IAP ≥20 mmHg exhibited significantly higher hospital mortality rates (p=0.006). Non-survivors had higher maximum and mean IAP values. Conclusions: Our results suggest that an elevated IAP may be associated with a poor prognosis in critically ill trauma patients.

Dexasone and metoclopramide vs. granisetron in the prevention of postoperative nausea and vomiting

Introduction. Postoperative nausea and vomiting (PONV) is one of the most common postoperative complications. The incidence in adult population is 20?30%, and it can be up to 80% in high-risk population such as gynecological and laparoscopic surgeries. The objective of this study is to compare the efficiency of the combination therapy in comparison with monotherapy in the prevention of PONV in gynecological and laparoscopic surgeries. Methods. An observational prospective cohort study was conducted on a sample of 64 patients (32 patients per group) treated postoperatively at the Gynecology and Obstetrics Ward of GH Subotica, in the period from January?March 2017. The anesthesiologist in charge administered the combination of dexasone and metoclopramide or granisetron in monotherapy according to protocol to patients for prevention of PONV. Results. The demographic characteristics of patients are homogenous and show a statistically significant difference only in the characteristics of length of smoker status and maximum intra-abdominal pressure during surgery. The total incidence of postoperative nausea in the fifth, 15th and 60th minute was 15.6%, 17.2% and 18.7% respectively, and in the fourth, eighth, 12th, and 24th postoperative hour it was 12.5%, 7.8%, 10.9%, and 6.2%, respectively. The incidence of postoperative vomiting in the fifth, 15th, and 60th minute was 1.6%, 4.7%, and 4.7%, respectively, and in the fourth, eighth, 12th, and 24th postoperative hour it was 1.6%, 3.2%, 1.6%, and 1.6%, respectively. Conclusion. The study proved that the combination effect of dexasone and metoclopramide is not inferior compared to monotherapy with granisetron.

Relationship between intra-abdominal hypertension, outcome and the revised Atlanta and determinant-based classifications in acute pancreatitis.

BackgroundThe aim of this study was to analyse the relationship between intra‐abdominal hypertension (IAH) and severity of acute pancreatitis (AP) measured by the revised Atlanta classification (RAC) and determinant‐based classification (DBC). Secondary objectives were to assess IAH as a predictor of morbidity and mortality in the ICU.MethodsThis prospective international observational study included patients admitted to the ICU with AP and at least one organ failure. Information was collected on demographics, severity scores at admission using RAC and DBC, organ failure, mechanical ventilation, continuous renal replacement therapy (CRRT), surgery and mortality. Maximum intra‐abdominal pressure (IAP) during ICU stay was used for analysis.ResultsSome 374 patients were included. The hospital mortality rate was 28·9 per cent. IAP was measured in 301 patients (80·5 per cent), of whom 274 (91·0 per cent) had IAH and 103 (34·2 per cent) acute compartment syndrome. A higher IAH grade was more likely in patients with severe AP (42 per cent for grade I versus 84 per cent for grade IV) and acute critical pancreatitis (9 versus 25 per cent; P = 0·001). Compared with grade I IAH, patients with grade IV had more infected necrosis (16 versus 28 per cent; P = 0·005), need for surgery (27 versus 50 per cent; P = 0·006), mechanical ventilation (53 versus 84 per cent; P = 0·007) and requirement for CRRT (22 versus 66 per cent; P < 0·001). IAH predicted shock (area under receiver operating characteristic (ROC) curve (AUC) 0·79, 95 per cent c.i. 0·73 to 0·84), respiratory failure (AUC 0·82, 0·77 to 0·87), renal failure (AUC 0·93, 0·89 to 0·96) and mortality (AUC 0·89, 0·86 to 0·93).ConclusionIAH was associated with severity of AP classified according to both RAC and DBC systems. IAP grade can predict outcome of AP during ICU stay.

Gastric regurgitation in patients undergoing gynecological laparoscopy with a laryngeal mask airway: a prospective observational study

ObjectiveThe use of pneumoperitonium and the placement of patients in Trendelenburg position are commonly cited reasons for the potential development of intraoperative regurgitation of gastric contents and the need for an endotracheal tube in laparoscopic surgery. The main objective of the current investigation was to evaluate the presence of regurgitation of gastric contents in the oropharynx of patients having laparoscopic gynecological surgery with a laryngeal mask airway (LMA). DesignProspective, observational clinical investigation. InterventionsNot applicable. MeasurementsHealthy subjects having a laparoscopic gynecological surgery under general anesthesia with a ProSeal LMA were included in the study. An insufflation pressure of 15 mm Hg was established as the maximum intra-abdominal pressure for the pneumoperitonium, and patients were placed in Trendelenburg position at a 15° angle. The pH of secretions extracted from subjects' hypopharynx was measured at multiple time points during the surgical procedure. A pH of oropharynx secretions ≤4.1 indicated the regurgitation of gastric contents. Main resultsEighty subjects were recruited and completed the study. The median (range) of pH measurements at any time (T3-T9) was 6.5 (5.5-7.0). The median (range) for the lowest pH for each subject was 6.0 (5.5-7.0). The lowest detected pH in the hypopharynx was not correlated (Spearman ρ) with total surgical time (P = .9), total pneumopertitonium time (P = .17), or total Trendelenburg position time (P = .47). ConclusionsOur current results suggest that the use of an LMA in healthy patients undergoing laparoscopic gynecological surgery may be safe. Future studies to confirm or refute our findings are warranted.

Risk factors of infected pancreatic necrosis secondary to severe acute pancreatitis

Severe acute pancreatitis (SAP) remains a clinical challenge with considerable morbidity and mortality. An early identification of infected pancreatic necrosis (IPN), a life-threatening evolution secondary to SAP, is obliged for a more preferable prognosis. Thus, the present study was conducted to identify the risk factors of IPN secondary to SAP. The clinical data of patients with SAP were retrospectively analyzed. Univariate and multivariate logistic regression analyses were sequentially performed to assess the associations between the variables and the development of IPN secondary to SAP. A receiver operating characteristic (ROC) curve was created for each of the qualified independent risk factors. Of the 115 eligible patients, 39 (33.9%) progressed to IPN, and the overall in-hospital mortality was 11.3% (13/115). The early enteral nutrition (EEN) (P=0.0092, OR=0.264), maximum intra-abdominal pressure (IAP) (P=0.0398, OR=1.131) and maximum D-dimer level (P=0.0001, OR=1.006) in the first three consecutive days were independent risk factors associated with IPN secondary to SAP. The area under ROC curve (AUC) was 0.774 for the maximum D-dimer level in the first three consecutive days and the sensitivity was 90% and the specificity was 58% at a cut-off value of 933.5 μg/L; the AUC was 0.831 for the maximum IAP in the first three consecutive days and the sensitivity was 95% and specificity was 58% at a cut-off value of 13.5 mmHg. The present study suggested that the maximum D-dimer level and/or maximum IAP in the first three consecutive days after admission were risk factors of IPN secondary to SAP; an EEN might be helpful to prevent the progression of IPN secondary to SAP.

Incidence and prognosis of intra-abdominal hypertension and abdominal compartment syndrome in severely burned patients: Pilot study and review of the literature.

Burn patients are at high risk for secondary intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) due to capillary leak and large volume fluid resuscitation. Our objective was to examine the incidence the incidence of IAH and ACS and their relation to outcome in mechanically ventilated (MV) burn patients. This observational study included all MV burn patients admitted between April 2007 and December 2009. Various physiological parameters, intra-abdominal pressure (IAP) measurements and severity scoring indices were recorded on admission and/or each day in ICU. Transpulmonary thermodilution parameters were also obtained in 23 patients. The mean and maximum IAP during admission was calculated. The primary endpoint was ICU (burn unit) mortality. Fifty-six patients were included. The average Simplified Acute Physiology Score (SAPS II) and Sequential Organ Failure Assessment (SOFA) scores were 43.4 (± 15.1) and 6.4 (± 3.4), respectively. The average total body surface area (TBSA) affected by burns was 24.9% (± 24.9), with 33 patients suffering inhalational injuries. Forty-four (78.6%) patients developed IAH and 16 (28.6%) suffered ACS. Patients with ACS had higher TBSAs burned (35.8 ± 30 vs. 20.6 ± 21.4%, P = 0.04) and higher cumulative fluid balances after 48 hours (13.6 ± 16L vs. 7.6 ± 4.1 L, P = 0.03). The TBSA burned correlated well with the mean IAP (R = 0.34, P = 0.01). Mortality was notably high (26.8%) and significantly higher in patients with IAH (34.1%, P = 0.014) and ACS (62.5%, P < 0.0001). Most patients received more fluids than calculated by the Parkland Consensus Formula while, interestingly, non-survivors received less. However, when patients with pure inhalation injury were excluded there were no differences. Non-surgical interventions (n = 24) were successful in removing body fluids and were related to a significant decrease in IAP, central venous pressure (CVP) and an improvement in oxygenation and urine output. Non-resolution of IAH was associated with a significantly worse outcome (P < 0.0001). Based on our preliminary results we conclude that IAH and ACS have a relatively high incidence in MV burn patients compared to other groups of critically ill patients. The percentage of TBSA burned correlates with the mean IAP. The combination of high CLI, positive (daily and cumulative) fluid balance, high IAP, high EVLWI and low APP suggest a poor outcome. Non-surgical interventions appear to improve end-organ function. Non-resolution of IAH is related to a worse outcome.

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

OBJECTIVE:Patients undergoing abdominal surgery are at risk for pulmonary complications. The principal cause of postoperative pulmonary complications is a significant reduction in pulmonary volumes (FEV1 and FVC) to approximately 65-70% of the predicted value. Another frequent occurrence after abdominal surgery is increased intra-abdominal pressure. The aim of this study was to correlate changes in pulmonary volumes with the values of intra-abdominal pressure after abdominal surgery, according to the surgical incision in the abdomen (superior or inferior).METHODS:We prospectively evaluated 60 patients who underwent elective open abdominal surgery with a surgical time greater than 240 minutes. Patients were evaluated before surgery and on the 3rd postoperative day. Spirometry was assessed by maximal respiratory maneuvers and flow-volume curves. Intra-abdominal pressure was measured in the postoperative period using the bladder technique.RESULTS:The mean age of the patients was 56±13 years, and 41.6% 25 were female; 50 patients (83.3%) had malignant disease. The patients were divided into two groups according to the surgical incision (superior or inferior). The lung volumes in the preoperative period showed no abnormalities. After surgery, there was a significant reduction in both FEV1 (1.6±0.6 L) and FVC (2.0±0.7 L) with maintenance of FEV1/FVC of 0.8±0.2 in both groups. The maximum intra-abdominal pressure values were similar (p = 0.59) for the two groups. There was no association between pulmonary volumes and intra-abdominal pressure measured in any of the groups analyzed.CONCLUSIONS:Our results show that superior and inferior abdominal surgery determines hypoventilation, unrelated to increased intra-abdominal pressure. Patients at high risk of pulmonary complications should receive respiratory care even if undergoing inferior abdominal surgery.

Intra-Abdominal Pressure in the Early Phase of Severe Acute Pancreatitis: Canary in a Coal Mine? Results from a Rigorous Validation Protocol

Background/AimsIntra-abdominal hypertension (IAH) is being increasingly reported in patients with severe acute pancreatitis (SAP) with worsened outcomes. The present study was undertaken to evaluate intra-abdominal pressure (IAP) as a marker of severity in the entire spectrum of acute pancreatitis and to ascertain the relationship between IAP and development of complications in patients with SAP.MethodsIAP was measured via the transvesical route by measurements performed at admission, once after controlling pain and then every 4 hours. Data were collected on the length of the hospital stay, the development of systemic inflammatory response syndrome (SIRS), multiorgan failure, the extent of necrosis, the presence of infection, pleural effusion, and mortality.ResultsIn total, 40 patients were enrolled and followed up for 30 days. The development of IAH was exclusively associated with SAP with an APACHE II score ≥8 and/or persistent SIRS, identifying all patients who were going to develop abdominal compartment syndrome (ACS). The presence of ACS was associated with a significantly increased extent of pancreatic necrosis, multiple organ failure, and mortality. The mean admission IAP value did not differ significantly from the value obtained after pain control or the maximum IAP measured in the first 5 days.ConclusionsIAH is reliable marker of severe disease, and patients who manifest organ failure, persistent SIRS, or an Acute Physiology and Chronic health Evaluation II score ≥8 should be offered IAP surveillance. Severe pancreatitis is not a homogenous entity.

Mechanical Response of the Herniated Human Abdomen to the Placement of Different Prostheses

This paper describes a method designed to model the repaired herniated human abdomen just after surgery and examine its static mechanical response to the maximum intra-abdominal pressure provoked by a physiological movement (standing cough). The model is based on the real geometry of the human abdomen bearing a large incisional hernia with several anatomical structures differentiated by MRI. To analyze the outcome of hernia repair, the surgical procedure was simulated by modeling a prosthesis placed over the hernia. Three surgical meshes with different mechanical properties were considered: an isotropic heavy-weight mesh (Surgipro®), a slightly anisotropic light-weight mesh (Optilene®), and a highly anisotropic medium-weight mesh (Infinit®). Our findings confirm that anisotropic implants need to be positioned such that the most compliant axis of the mesh coincides with the craneo-caudal direction of the body.

Invasive monitoring of the clinical effects of high intra-abdominal pressure for insertion of the first trocar.

Abstract Background: To analyze the effects of transitory, high intra-abdominal pressure on clinical, hemodynamic, blood gas and metabolic parameters.Methods: Sixty-seven laparoscopic patients were divided into groups P12 (n = 30, maximum intra-abdominal pressure of 12 mmHg) and P20 (n = 37, maximum intra-abdominal pressure of 20 mmHg). Through radial artery cannulation, mean arterial pressure (MAP) was assessed and blood gas analysis – pH, arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2), bicarbonate (HCO3) and base excess (BE) – was performed. These parameters were evaluated in both groups at time point zero, before CO2 insufflation; at time point one (TP1), when intra-abdominal pressure of 12 mmHg was reached in both groups; at time point two (TP2), 5 minutes after reaching intra-abdominal pressure of 12 mmHg in group P12 and of 20 mmHg in group P20; and at time point three (TP3), 10 minutes after reaching intra-abdominal pressure of 12 mmHg in group P12 and 10 minutes after TP1 in group P20, when intra-abdominal pressure decreased from 20 mmHg to 12 mmHg. Values out of the normal range or the occurrence of atypical phenomena suggestive of organic disease indicated clinical changes. Results: Significant variations in MAP, pH, HCO3 and BE were observed in group P20; these changes, however, were within normal limits. Clinical changes were also within normal limits, and no pathological phenomena were observed. Conclusions: Brief, intra-abdominal hypertension for the insertion first trocar insertion causes variations in MAP, pH, HCO3 and BE without adverse effects, and it may protect from iatrogenic injury.

Preoperative progressive pneumoperitoneum for giant inguinal hernias

Reduction of giant hernia contents into the abdominal cavity may cause intraoperative and postoperative problems such as abdominal compartment syndrome. Preoperative progressive pneumoperitoneum expands the abdominal cavity, increases the patient’s tolerability to operation, and can diminish intraoperative and postoperative complications. Preoperative progressive pneumoperitoneum is recommended for giant ventral hernias, but rarely for giant inguinal hernias. We present two giant inguinal hernia patients who were prepared for hernia repair with preoperative progressive pneumoperitoneum and then treated successfully by graft hernioplasty. We observed that abdominal expansion correlated with the inflated volume and pressure during the first four days of pneumperitoneum. Although insufflated gas volume can be different among patients, we observed that the duration of insufflation may be the same for similar patients.

Usefulness of intra-abdominal pressure in a predominantly medical intensive care unit

Background The deleterious effects of elevated intra-abdominal pressure (IAP) have been known for more than a century. The proposed objectives were to measure changes in IAP and analyze increase-related factors and complications and whether high IAP and its persistence are related to complications and mortality in a predominantly medical intensive care unit. Methods Over a 1-year period, we conducted a prospective cohort study in which IAP was measured using the bladder method. Hospitalization time, demographic variables, diagnosis on admission, APACHE II score, and clinical complications were recorded. Results A total of 130 patients were studied. Overall mean IAP was 12.3 mm Hg (standard deviation [SD], 3.79; 95% confidence interval [CI], 11.7-13), and on the first day, 12.68 mm Hg (SD, 5.32; 95% CI, 11.8-13.6); maximum IAP was 16.4 mm Hg (SD, 4.6; 95% CI, 15.6-17.2). A positive correlation was found between IAP, APACHE (Acute Physiology And Chronic Health Evaluation) II, and age. Higher IAP values were independently associated with higher age, prolonged activated partial thromboplastin time, need for dialysis, and intolerance to enteral feeding. The value showing the best sensitivity and specificity in predicting mortality was persistence of IAP 20 mm Hg or greater for 4 days or more. The number of days with IAP 20 mm Hg or greater was a factor associated with a higher risk of death (odds ratio, 2.3). Patients who died showed a tendency to increased IAP. Conclusion In this study, a threshold IAP of 20 mm Hg and its permanence over time were the best predictive factors of complications and mortality. Among other relationships, we also observed that older patients had higher IAP. High IAP was a cause of intolerance to enteral nutrition.

Dan Hicks and Mary C. Beaudry (eds), The Cambridge Companion to Historical Archaeology. (Cambridge: Cambridge University Press, 2006, 404 pp., 31 figs, 1 table, ISBN (hbk) 978 0 521 85375 0, (pbk) 978 0 521 61962 2)

We studied the haemodynamic effects of intra-abdominal insufflation with either CO2 (n = 15) or N2O (n = 15) in patients undergoing laparoscopic surgery. Haemodynamic variables were measured at increasing levels of intra-abdominal pressure up to 20 mmHg. In the CO2 group cardiac index decreased from 2.6 +/- 0.6 to 2.0 +/- 0.4 litre min-1 m-2 (mean +/- SD, P < 0.001) and in the N2O group from 2.6 +/- 0.5 to 1.8 +/- 0.4 litre min-1 m-2 (P < 0.001)). In the CO2 group, this was accompanied by increases in mean arterial pressure, systemic vascular resistance index and central venous pressure without change in heart rate. In contrast, during N2O insufflation mean arterial pressure decreased (from 77 +/- 8 to 63 +/- 15 mmHg (P < 0.001)) without change in vascular resistance. No further changes in haemodynamic variables were observed during head-up tilt in both groups. After desufflation mean arterial pressure increased in the N2O group to pre-insufflation levels and cardiac index increased in both groups (P < 0.001), but reached pre-insufflation levels only in the CO2 group. In both groups central venous O2 tension and saturation decreased at maximum intra-abdominal pressure and increased after release of the pneumoperitoneum. The results indicate that laparoscopic insufflation with either CO2 or N2O results in cardiovascular depression. Insufflation with N2O may decrease blood pressure, whereas mean arterial pressure is better preserved with CO2 insufflation.

The real intraabdominal pressure during laparoscopy: Comparison of different insufflators

Study objective To compare 5 laparoscopic insufflators with different gas flow rates with regard to accuracy of preset pressure setting versus real intraoperative intraabdominal pressure. Design Prospective study (Canadian Task Force classification II-2). Setting Fayette Medical Center, Alabama. Patients Five patients undergoing laparoscopic cholecystectomy. Interventions Intraoperative intraabdominal and system pressure measurements during comparable laparoscopic procedures. Measurements and main results Actual intraabdominal pressure was measured and compared between 5 different 10 to 20 L/min insufflators (Storz Laparoflator and Endoflator, Richard Wolf, BEI Medical and Snowden & Pencer) with a computer-based online data acquisition system. At a nominal pressure of 10 mm Hg, the mean intraabdominal pressure during the entire procedure was measured to be between 9.68 and 11.45 mm Hg. The mean intraabdominal pressure during laparoscopy for the insufflators showed a margin of error of 14.5%, with maximum intraabdominal pressure peaks measured between 14.65 and 17.87 mm Hg. Conclusions Within an error margin of <15% of the preset intraabdominal pressure setting, the insufflators evaluated can be considered pressure reliable. Although intraabdominal pressure peaks exceeding the nominal pressure temporarily reached up to 78.7% of the setting, no apparent complications were observed. Excessive pressure peaks seen in the previous reported laboratory model could not be confirmed during in vivo application.

Special issue—Collagen

Hernia is the most frequent surgical disease with an overall incidence of more than 10% of the total population and at least the same percentage of the average surgeon’s workload. Since its Wrst description more than 4,000 years ago by Babylonians and Egyptians, hernia has always been understood as a mechanical defect of the abdominal wall caused by trauma, heavy weight lifting, or maximum intraabdominal pressure. Because the etiology of hernia was suspected to be a mechanical problem, traditional surgery consisted of mechanical repair by suture, i.e. direct closure of the hernia defect by suturing. Although this repair usually succeeds, hernias recur at a rate of 10–15%, despite the best mechanical suture repair. At the beginning of the 20th century, understanding of hernia as a simple mechanical defect was questioned by some anatomists, who asked about the connective tissue and its role in hernia development. The Wrst systematic discussion of hernia as a disease of the connective tissue was that of Raymond Read in the 1960s, with many studies and papers on hernia as a result of weak collagen. Since these pioneering publications much evidence has accumulated suggesting hernia disease can no longer be regarded as a simple mechanical defect but must be understood as a connective tissue problem. The demographic development of our population furnishes evidence of an inverse correlation between mechanical activity and hernia incidence—the older the patients the higher is the incidence of hernia and the less the strength of the connective tissue. Surgeons from all over the world therefore agree that we must understand hernia as a connective tissue disorder that can be treated only in very few young patients by simple suture and must be handled in most patients by mesh augmentation. This understanding of collagen disease is the reason for the increased use of mesh in hernia surgery today; it will continue as long as we have no pharmaceutical method available to increase the strength of the weak collagen. It was Raymond Reads proposal to arrange a special supplement on collagen disease in the “Hernia” journal. Authors from diVerent groups worldwide have participated in this collection and present diVerent aspects of the collagen problem in hernia disease. One can see that since the Wrst discussions of hernia as a collagen disorder much evidence and knowledge has been accumulated, enabling slightly better understanding and treatment of this misunderstood “mechanical” problem. Because Raymond Read was the pioneer of this new understanding of hernia as a collagen disease, this volume is dedicated to this great researcher and surgeon, the nestor of modern hernia surgery.