scholarly journals Severe portal and systemic acidosis during CO2-laparoscopy compared to helium or gasless laparoscopy and laparotomy in a rodent model: an experimental study

Author(s):  
Devdas T. Inderbitzin ◽  
Tobias U. Mueller ◽  
Grischa Marti ◽  
Simone Eichenberger ◽  
Benoît Fellay ◽  
...  

Abstract Background and aims This experimental study assesses the influence of different gases and insufflation pressures on the portal, central-venous and peripheral-arterial pH during experimental laparoscopy. Methods Firstly, 36 male WAG/Rij rats were randomized into six groups (n = 6) spontaneously breathing during anaesthesia: laparoscopy using carbon dioxide or helium at 6 and 12 mmHg, gasless laparoscopy and laparotomy. 45 and 90 min after setup, blood was sampled from the portal vein, vena cava and the common femoral artery with immediate blood gas analysis. Secondly, 12 animals were mechanically ventilated at physiological arterial pH during 90 min of laparotomy (n = 6) or carbon dioxide laparoscopy at 12 mmHg (n = 6) with respective blood gas analyses. Results Over time, in spontaneously breathing rats, carbon dioxide laparoscopy caused significant insufflation pressure-dependent portal acidosis (pH at 6 mmHg, 6.99 [6.95–7.04] at 45 min and 6.95 [6.94–6.96] at 90 min, pH at 12 mmHg, 6.89 [6.82–6.90] at 45 min and 6.84 [6.81–6.87] at 90 min; p < 0.05) compared to laparotomy (portal pH 7.29 [7.23–7.30] at 45 min and 7.29 [7.20–7.30] at 90 min; p > 0.05). Central-venous and peripheral-arterial acidosis was significant but less severely reduced during carbon dioxide laparoscopy. Laparotomy, helium laparoscopy and gasless laparoscopy showed no comparable acidosis in all vessels. Portal and central-venous acidosis during carbon dioxide laparoscopy at 12 mmHg was not reversible by mechanical hyperventilation maintaining a physiological arterial pH (pH portal 6.85 [6.84–6.90] (p = 0.004), central-venous 6.93 [6.90–6.99] (p = 0.004), peripheral-arterial 7.29 [7.29–7.31] (p = 0.220) at 90 min; Wilcoxon–Mann–Whitney test). Conclusion Carbon dioxide laparoscopy led to insufflation pressure-dependent severe portal and less severe central-venous acidosis not reversible by mechanical hyperventilation.

2019 ◽  
Vol 6 (5) ◽  
pp. 1947
Author(s):  
Mohd Kashif Ali ◽  
Eeman Naim

Background: Ultrasound guided fluid assessment in management of septic shock has come up as an adjunct to the current gold standard Central Venous Pressure monitoring. This study was designed to observe the respiro-phasic variation of IVC diameter (RV-IVCD) in invasively mechanically ventilated and spontaneously breathing paediatric patients of fluid refractory septic shock.Methods: This was a prospective observational study done at Paediatric intensive Care Unit (PICU) in Paediatric ward of Jawaharlal Nehru Medical College and Hospital (JNMCH) from February 2016 to June 2017. 107 consecutive patients between 1 year to 16 years age who were in shock despite 40ml/kg of fluid administration were included. Inferior Vena Cava (IVC) diameters were measured at end-expiration and end inspiration and the IVC collapsibility index was calculated. Simultaneously Central Venous Pressure (CVP) was recorded. Both values were obtained in ventilated and non-ventilated patients. Data was analysed to determine to look for the profile of RV-IVCD and CVP in ventilated and non-ventilated cases.Results: Out of 107 patients, 91 were on invasive mechanical ventilation and 16 patients were spontaneously breathing. There was a strong negative correlation between central venous pressure (CVP) and inferior vena cava collapsibility (RV-IVCD) in both spontaneously breathing (-0.810) and mechanically ventilated patients (-0.700). Negative correlation was significant in both study groups in CVP <8 mmHg and only in spontaneously breathing patients in CVP 8-12 mmHg range. IVC collapsibility showed a decreasing trend with rising CVP in both spontaneously breathing and mechanically ventilated patients.Conclusion: Ultrasonography guided IVCCI appears to be a valuable index in assessing fluid status in both spontaneously breathing and mechanically ventilated septic shock patients. However, more data is required from the paediatric population so as to define it as standard of practice.


2008 ◽  
Vol 60 (6) ◽  
pp. 1461-1467
Author(s):  
A.P. Ribeiro ◽  
S.N. Vitaliano ◽  
R. Thiesen ◽  
A. Escobar ◽  
J.P. Duque Ortiz ◽  
...  

The intraocular pressure (IOP) and its correlations with arterial carbon dioxide partial pressure (PaCO2) and arterial pH were studied in five crested caracaras (Caracara plancus) anesthetized with isoflurane (ISO) and sevoflurane (SEV). Baseline IOP values were measured in both eyes (M0). Brachial artery was previously catheterized to obtain blood gas and cardiorespiratory analysis. Anesthesia was induced with 5% ISO and maintained with 2.5% for 40 minutes. IOP measurements and blood samples were evaluated in different moments until the end of the procedure. After recovering, a second anesthesia was induced with 6% SEV and maintained with 3.5%. Parameters were evaluated at the same time points of the previous procedure. IOP reduced significantly (P= 0.012) from M0 at all time points and no significative changes were observed between ISO and SEV anesthesias. Correlation between IOP and PaCO2 and between PIO and blood pH were found only for SEV. IOP and blood pH decreased in parallel with IOP, whereas values of PaCO2 increased in caracaras anesthetized with isoflurane and sevoflurane.


2019 ◽  
Vol 21 (1) ◽  
pp. 64-71
Author(s):  
Vinodh B Nanjayya ◽  
Phoebe McCracken ◽  
Shirley Vallance ◽  
Jasmin Board ◽  
Patrick J Kelly ◽  
...  

Background In critically ill patients, who require multiple blood gas assessments, agreement between arterial and venous blood gas values for pH and partial pressure of carbon dioxide, is not clear. Good agreement would mean that venous values could be used to assess ventilation and metabolic status of patients in intensive care unit. Methods All adult patients admitted to Alfred intensive care unit, Melbourne, from February 2013 to January 2014, who were likely to have arterial and central venous lines for three days, were enrolled. Patients on extra-corporeal life support and pregnant women were excluded. After enrolment, near simultaneous arterial and central venous sampling and analysis were performed at least once per nursing shift till the lines were removed or the patient died. Bland-Altman analysis for repeated measures was performed to assess the agreement between arterio-venous pH and partial pressure of carbon dioxide. Results A total of 394 paired blood gas analyses were performed from 59 participants. The median (IQR) number of samples per patient was 6 (5–9) with the median (IQR) sampling interval 9.4 (5.2–18.5) h. The mean bias for pH was  + 0.036 with 95% limits of agreement ranging from − 0.005 to + 0.078. For partial pressure of carbon dioxide, the values were −2.58 and −10.43 to + 5.27 mmHg, respectively. Conclusions The arterio-venous agreement for pH in intensive care unit patients appears to be acceptable. However, the agreement for partial pressure of carbon dioxide was poor.


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4225
Author(s):  
Rafael Costa Guilhen ◽  
Renata Navarro Cassu ◽  
Miriely Steim Diniz ◽  
Rogério Giuffrida ◽  
Rodrigo Rolim Duarte

This study aimed to compare the sedative and cardiopulmonary effects of detomidine in combination with saline, morphine or methadone and to determine whether the addition of these opioids increases the degree of sedation in horses submitted to experimental oral stimuli. In a blinded, randomized, experimental study, six adult mares were evaluated using a crossover design with at least 15 days between trials: 10?g/kg detomidine in combination with saline (D/SAL), 0.1mg/kg morphine (D/ MORPH) or 0.1mg/kg methadone (D/METH). The degree of sedation, response to oral stimuli and cardiopulmonary parameters were monitored for 120 minutes. Parametric data were analyzed using the ANOVA and Tukey’s tests, and non- parametric data were analyzed with the Kruskal-Wallis and Friedman’s tests with the post-Dunn test (P<0.05). The degree of sedation was significantly greater for the D/SAL than for the D/MORPH and D/METH treatments at 30 min. The horses´ responses to the oral stimuli decreased significantly following all treatments at 5 and 30 min from baseline values. The heart rate, respiratory rate, arterial pH and blood gas variables were all similar among the treatment groups. Mean arterial blood pressure was significantly higher in the D/MORPH group when compared with the D/SAL group between 75 and 120 min. It was concluded that all treatments provided sedative effects with mild cardiopulmonary changes. However the addition of morphine or methadone to detomidine did not improve the degree of sedation in horses submitted to experimental oral stimuli.


1989 ◽  
Vol 12 (6) ◽  
pp. 384-389 ◽  
Author(s):  
JD Mortensen ◽  
G. Berry

Conceptual and design features of a new intravascular blood gas exchange device include: placing multiple, thin-walled microporous hollow fibers in an elongated arrangement with a small overall outside diameter; covering the outer surface of each microporous hollow fiber with an ultrathin continuous silicone coating; forming the hollow fibers into a configuration that produces disturbed flow of blood over the external surface of each fiber; placing the device in the subject's vena cava through a femoral or jugular venotomy; producing a flow of oxygen through the lumens of the hollow fibers, permitting exchange of oxygen and carbon dioxide between the venous blood outside and the gas inside the hollow fibers. Based on these principles, a practical, easily insertible, disposable, intravenacaval blood gas exchange device (IVOX) has been fabricated. Currently, devices with from 2,000 to 6,000 square centimeters of gas transfer surface area are being placed in the vena cavae of dogs and sheep for up to 7 days without altering the animal's hemodynamics, without producing serious hematologic sequelae, and with the capability of transferring in excess of 100 ml of oxygen and carbon dioxide to and from the venous blood of an intact, awake, standing animal. Clinical trials on human subjects with severe, acute, potentially reversible respiratory failure are in the planning stage.


1998 ◽  
Vol 76 (2) ◽  
pp. 118-124
Author(s):  
Timothy A Cudd

Thromboxane A2 (TxA2), well known as a vasoconstrictor and activator of platelets, also stimulates reflex cardiovascular, pituitary, adrenocortical, and blood gas responses, although the site of action is unknown. Previously we determined that the site of these actions is perfused by the carotid vasculature. The purpose of the present study was to test the hypothesis that TxA2 stimulates these responses by acting at the carotid sinus. The TxA2 mimetic U46619 (1 µg ·kg-1 ·min-1) or saline was infused into the carotid artery (CA) or vena cava in conscious, chronically instrumented carotid sinus denervated (CSD) or sham-operated sheep. Mean arterial pressure increased in all groups receiving U46619. Heart rate increased only in the CSD group receiving CA infusions of U46619. Adrenocorticotropic hormone (ACTH) and cortisol increased in the sham and CSD groups receiving CA U46619, and responses were not different between sham and CSD groups. PaCO2 values were higher in all CSD treatment groups compared with sham treatment groups. Arterial pH increased and PaCO2 decreased in both the sham and CSD groups in response to CA U46619. Although PaCO2 values were higher overall in the CSD group, the magnitude of change in response to U46619 infusions was similar in sham and CSD animals. There was no difference in pHa between CSD and sham groups. Hematocrit and PaO2 did not change. We conclude that TxA2 does not act at the carotid sinus, as responses to U46619 infusions in CSD animals were not different in the cases of ACTH, cortisol, and blood gases, or were enhanced rather than diminished in the case of heart rate. These findings support a hypothesis that TxA2 acts at the brain to mediate cardiovascular, pituitary, adrenocortical, and blood gas responses.Key words: ACTH, thromboxane A2, blood pressure, heart rate, prostaglandins, U46619.


2018 ◽  
pp. 721-728 ◽  
Author(s):  
P. SVORC ◽  
D. PETRÁŠOVÁ ◽  
P. SVORC

The aim of study was to review the status of arterial pH, pO2 and pCO2 under general anesthesias in dependence on the light-dark (LD) cycle in spontaneously breathing rats. The experiments were performed using three- to four-month-old pentobarbital(P)-, ketamine/xylazine(K/X)- and zoletil(Z)-anesthetized female Wistar rats after a four-week adaptation to an LD cycle (12 h light:12 h dark). The animals were divided into three experimental groups according to the anesthetic agent used: P (light n=11; dark n=8); K/X (light n=13; dark n=11); and Z (light n=18; dark n=26). pH and blood gases from arterial blood were analyzed. In P anesthesia, LD differences in pH, pO2, and pCO2 were eliminated. In K/X anesthesia, parameters showed significant LD differences. In Z anesthesia, LD differences were detected for pH and pO2 only. Acidosis, hypoxia, and hypercapnia have been reported for all types of anesthesia during the light period. In the dark period, except for P anesthesia, the environment was more stable and values fluctuated within normal ranges. From a chronobiological perspective, P anesthesia was not the most appropriate type of anesthesia in these rat experiments. It eliminated LD differences, and also produced a more acidic environment and more pronounced hypercapnia than K/X and Z anesthesias.


2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4225
Author(s):  
Rafael Costa Guilhen ◽  
Renata Navarro Cassu ◽  
Miriely Steim Diniz ◽  
Rogério Giuffrida ◽  
Rodrigo Rolim Duarte

<p>This study aimed to compare the sedative and cardiopulmonary effects of detomidine in combination with saline, morphine or methadone and to determine whether the addition of these opioids increases the degree of sedation in horses submitted to experimental oral stimuli. In a blinded, randomized, experimental study, six adult mares were evaluated using a crossover design with at least 15 days between trials: 10?g/kg detomidine in combination with saline (D/SAL), 0.1mg/kg morphine (D/ MORPH) or 0.1mg/kg methadone (D/METH). The degree of sedation, response to oral stimuli and cardiopulmonary parameters were monitored for 120 minutes. Parametric data were analyzed using the ANOVA and Tukey’s tests, and non- parametric data were analyzed with the Kruskal-Wallis and Friedman’s tests with the post-Dunn test (P&lt;0.05). The degree of sedation was significantly greater for the D/SAL than for the D/MORPH and D/METH treatments at 30 min. The horses´ responses to the oral stimuli decreased significantly following all treatments at 5 and 30 min from baseline values. The heart rate, respiratory rate, arterial pH and blood gas variables were all similar among the treatment groups. Mean arterial blood pressure was significantly higher in the D/MORPH group when compared with the D/SAL group between 75 and 120 min. It was concluded that all treatments provided sedative effects with mild cardiopulmonary changes. However the addition of morphine or methadone to detomidine did not improve the degree of sedation in horses submitted to experimental oral stimuli.</p>


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