Min Of Pneumoperitoneum Research Articles

ANALYSIS OF THE BASKA MASK VERSUS PROSEAL LARYNGEAL MASK AIRWAY SEALING PRESSURE IN PATIENTS POSTED FOR LAPAROSCOPIC SURGERIES UNDER GENERAL ANAESTHESIA

Background: Airway management by anaesthesiologist has come a long way from the invention of endotracheal intubation. Invention of supraglottic airway devices (SAD) provided alternative airway, without hazards of direct laryngoscopy and intubation. First generation SAD was considered airway tubes, and hence modications were made to them. PLMA (Proseal laryngeal mask airway) is a second generation SAD which has a gastric port along with the airway tube. BASKA mask is a novel 3rd generation SAD. We designed this study to compare the clinical efcacy of BASKA mask and PLMA for time for insertion, ease of insertion, airway sealing pressure and complications in anaesthetised patients undergoing positive pressure ventilation under general anaesthesia. The present randomi Methodology: zed control trial was conducted in 60 ASA-1 and ASA-2, aged between 18-60 years posted for elective laparoscopic surgeries under general anaesthesia. Patients were allocated into two equal groups, Group B-BASKA mask (n=30) and Group P- PLMA (n=30). All the data Collected were analysed. The demographic data, duration of insertion and airway sealing pressure were analysed using unpaired't' test. In our study we observed that, BASKA mask took lesser time to ins Results: ert in comparison to PLMA, the mean duration of insertion was 16.77±2.14 sec in BASKA Mask and 25.40±3.04 sec in PLMA Group. This difference was statistically signicant (p < 0.0001). The Mean airway sealing pressure was 33±2.31 cm of H2O in BASKA mask group and 27.00±1.84 cm of H2O in PLMA Group, after 5 min of insertion and 31.33±2.06 cm of H20 in BASKA Mask and 26.90±1.79 cm of H2O in PLMA Group after 5 min of pneumoperitoneum. The airway sealing pressure was more in BASKA group which was statistically signicant both after 5 min insertion and 5 min of pneumoperitoneum. There were no signicant mean airway sealing pressures between 5 min after insertion and 5 min after pneumoperitoneum in both the groups. The ease of insertion was more in BASKA mask but it was statistically insignicant. The Laryngopharyngeal morbidity score between these groups were statistically insignicant. To conclude, we observed that BASKA mask took lesser time to insert Conclusion: than PLMA in anaesthetized paralysed adult patients. Mean airway sealing pressure was higher in BASKA mask than PLMA. The ease of insertion was more in BASKA mask but it was statistically insignicant. The LPM score between these groups were statistically insignicant.

Effect of dexmedetomidine on acute lung injury in patients undergoing retroperitoneal laparoscopic surgery

Objective To investigate the effect of dexmedetomidine on acute lung injury in the patients undergoing retroperitoneal laparoscopic surgery. Methods Forty patients of both sexes, aged 18-60 yr, weighing 50-80 kg, of American Society of Anesthesiologist physical statusⅠor Ⅱ, scheduled for elective retroperitoneal laparoscopic partial nephrectomy, were divided into either control group(group C, n=20)or dexmedetomidine group(group Dex, n=20)using a random number table.At 10 min before induction of anesthesia, dexmedetomidine was injected intravenously in a loading dose of 1.0 μg/kg, followed by an infusion of 0.5 μg·kg-1·h-1 throughout surgery in group Dex, and the equal volume of normal saline was given instead in group C. The patients were placed in lateral position after anesthesia, and CO2 pneumoperitoneum was induced with an intra-abdominal pressure of 12 mmHg.Before induction of anesthesia(T0), at 60 and 120 min of pneumoperitoneum(T1, 2), and at 15 and 60 min after deflation(T3, 4), peripheral venous blood samples were taken for determination of serum malondialdehyde(MDA), tumor necrosis factor-alpha(TNF-α), interleukin-6(IL-6)and Clara cell 16-kDa secretory protein(CC16)concentrations by enzyme-linked immunosorbent assay. Results Compared with the baseline at T0, the serum MDA, TNF-α, IL-6 and CC16 concentrations were significantly increased at T1-4 in group C, and the serum MDA concentrations at T3, 4, serum TNF-α and IL-6 concentrations at T1-4 and serum concentrations of CC16 at T2-4 were significantly increased in group Dex(P<0.05). Compared with group C, the serum MDA, TNF-α, and CC16 concentrations at T2-4 and serum IL-6 concentrations at T1-4 were significantly decreased in group Dex(P<0.05). Conclusion Dexmedetomidine can reduce acute lung injury in the patients undergoing retroperitoneal laparoscopic surgery. Key words: Dexmedetomidine; Pneumoperitoneum, artificial; Respiratory distress syndrome, adult

The effects of adding ischemic preconditioning during desflurane inhalation anesthesia or propofol total intravenous anesthesia on pneumoperitoneum-induced oxidative stress

Background: The aim of the study was to explore the differences in oxidative stress during anesthesia with desflurane/N2O or propofol/remifentanil in patients undergoing laparoscopic cholecystectomy and additionally to evaluate the differential effects of desflurane and propofol on ischemic preconditioning (IP).Materials and methods: One hundred patients were randomly allocated to four groups. For anesthesia maintenance, the inhalation group (Group I) and the inhalation plus IP group (Group IIP) received desflurane at an end-tidal concentration of 4–6 vol% in oxygen/N2O, and the TIVA group (Group T) and TIVA plus IP group (Group TIP) received infusions of propofol and remifentanil. In Groups IIP and TIP, IP was carried out by 10 min of pneumoperitoneum followed by 10 min of deflation. Preoperative and postoperative plasma total antioxidant status (TAS), total oxidant status (TOS), paraoxonase, stimulated paraoxonase, arylesterase, ceruloplasmin, and myeloperoxidase levels were analyzed; oxidative stress index (OSI) was calculated.Results: When oxidative stress parameters were compared between groups, myeloperoxidase values in Group I were statistically significantly lower compared to Group TIP (p = .004 with Bonferroni’s correction). There were no differences between preoperative and postoperative TAS, paraoxonase, stimulated paraoxonase, arylesterase, or ceruloplasmin levels (p > .05). In intragroup evaluations, postoperative paraoxonase and stimulated paraoxonase levels were found to be lower than preoperative values in Group TIP (p = .021 and .012, respectively).Conclusion: In laparoscopic cholecystectomy lasting less than 60 min, there were no differences in the measured oxidative stress parameters between maintenance of anesthesia by desflurane/N2O and propofol/remifentanil/N2O. The addition of 10 min IP administration during both anesthesia techniques did not result in additional changes in the analyzed oxidative stress.

Effects of long-term glucocorticoid administration on cisatracurium-induced neuromuscular blockade in patients undergoing laparoscopic operation

Objective To evaluate the effects of long-term glucocorticoid administration on cisatracurium-induced neuromuscular blockade in the patients undergoing laparoscopic operation. Methods Sixty-four patients of both sexes, aged 40-64 yr, with body mass index of 18-22 kg/m2, of American Society of Anesthesiologists physical status Ⅱ or Ⅲ, scheduled for elective laparoscopic operation under general anesthesia, were assigned into 4 groups (n=16 each) according to whether or not glucocorticoid was used for a long-term period: control (non-hormone and non-laparoscopic operation) group (group C), hormone + laparoscopic operation group (group HL), non-hormone + laparoscopic operation group (group NHL) and hormone + non-laparoscopic operation group (group HNL). Midazolam 0.03 mg/kg was injected intravenously, 8% sevoflurane was inhaled by mask, and the concentration of sevoflurane was decreased by 2% every 30 s until the concentration of 4% was reached.After loss of eyelash reflex, remifentanil 2 μg/kg was injected intravenously over 1 min, and 30 s later sevoflurane inhalation was stopped.The patients were tracheally intubated and mechanically ventilated.Anesthesia was maintained with propofol and remifentanil given by target-controlled infusion.Neuromuscular blockade was monitored with accelerograph TOF-watch SX.At 20 min of pneumoperitoneum in NHL and HL groups or 20 min after intubation in C and HNL groups, cisatracurium 0.15 mg/kg was injected intravenously.The onset time, maximal degree of N-M block, clinical duration and recovery index of cisatracurium were recorded. Results Compared with group C, the onset time was significantly prolonged, the maximal degree of N-M block was decreased, the clinical duration was shortened, and the recovery index was decreased in HL and HNL groups (P 0.05). Compared with group HNL, the clinical duration was significantly prolonged, the recovery index was increased (P 0.05), and the onset time was significantly shortened, the clinical duration was prolonged, and the recovery index was increased in group NHL (P<0.05). Compared with group NHL, the onset time was significantly prolonged, the maximal degree of N-M block was decreased, the clinical duration was shortened, and the recovery index was decreased in group HL (P<0.05). Conclusion Long-term glucocorticoid administration can weaken cisatracurium-induced neuromuscular blockade in the patients undergoing laparoscopic operation. Key words: Glucocorticoids; Laparoscopes; Atracurium

Effect of positive end-expiratory pressure on intraoperative pulmonary function in patients undergoing urological retroperitoneal laparoscopic surgery in mode of protective ventilation

Objective To evaluate the effect of positive end-expiratory pressure (PEEP) on intraoperative pulmonary function in the patients undergoing urological retroperitoneal laparoscopic surgery in the mode of protective ventilation. Methods Forty patients of both sexes, aged 30-64 yr, with body mass index of 16-29 kg/m2, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, scheduled for elective retroperitoneal laparoscopic ureterolithotomy, were randomly divided into 2 groups (n=20 each) using a random number table: control group (group C) and PEEP group (group P). After induction of general anesthesia, the patients were endotracheally intubated.Intermittent positive pressure ventilation (tidal volume [VT] 6 ml/kg, respiratory rate [RR] 12 breaths/min, inspiratory/expiratory ratio [I∶E] 1∶2, fraction of inspired oxygen 50%) was performed from the end of intubation until the onset of pneumoperitoneum.After the onset of pneumoperitoneum, the patients were ventilated (VT 6 ml/kg, RR 22 breaths/min, I∶E 1.0∶1.5), and the end-tidal pressure of carbon dioxide was maintained at 35-45 mmHg in group C. After the onset of pneumoperitoneum, the patients were ventilated (VT 6 ml/kg, RR 22 breaths/min, I∶E 1.0∶1.5, PEEP 5 cmH2O), and the end-tidal pressure of carbon dioxide was maintained at 35-45 mmHg in group P. At 5 min before pneumoperitoneum (T1), at 10, 30 and 60 min of pneumoperitoneum (T2-4), immediately after the end of pneumoperitoneum (T5), and at 5 min before extubation (T6), arterial blood samples were collected for blood gas analysis.Peak airway pressure and mean airway pressure were also recorded.Dynamic lung compliance, oxygenation index, respiratory index, dead space fraction and alveolar-arterial oxygen gradient were calculated. Results Compared with group C, mean airway pressure was significantly higher at T2-4, oxygenation index was significantly higher at T3, alveolar-arterial oxygen gradient difference was significantly lower at T3 and T6, and respiratory index was significantly lower at T6 (P 0.05). Conclusion PEEP (5 cmH2O) can improve the intraoperative pulmonary function in the patients undergoing urological retroperitoneal laparoscopic surgery in the mode of protective ventilation. Key words: Positive-pressure respiration; Respiratory function tests; Laparoscopy; Urologic surgical procedures

Comparison of cerebral oxygenation inpatients undergoing gynecological laparoscopic surgery under sevoflurane- versus propofol-based anesthesia

Objective To compare the cerebral oxygenation in the patients undergoing gynecological laparoscopic surgery under sevoflurane- versus propofol-based anesthesia. Methods Fifty adult patients, aged 18-56 yr, weighing 55-72 kg, of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, with hemoglobin≥110 g/L, undergoing elective gynecological laparoscopic surgery under general anesthesia, were equally and randomly divided into sevoflurane group(group S)and propofol group(group P)using a random number table.Anesthesia was induced with iv midazolam 0.04 mg/kg, sufentanil 1.5-2.0 μg/kg, rocuronium 0.9 mg/kg, and propofol 1.5-2.0 mg/kg.Anesthesia was maintained with inhalation of sevoflurane(2.0%-2.6%)in group S, or with target-controlled infusion of propofol(plasma concentration 2.5-4.0 μg/ml)in group P. The concentrations of sevoflurane and propofol were adjusted to maintain bispectral index value at 40-50.In both groups, remifentanil was given by target-controlled infusion(target plasma concentration 2 ng/ml), and vecuronium 0.06-0.08 mg/kg was injected intermittently to maintain muscle relaxation.The regional cerebral oxygen saturation(rSO2)was recorded after induction and at 10 min before pneumoperitoneum(T1), at 10 min of pneumoperitoneum in the Trendelenburg position(T2), and at 10 min after the end of pneumoperitoneum(T3). The occurrence of cerebral oxygen desaturation was recorded during surgery. Results The rSO2 was significantly higher at T2, 3 in group S than in group P(P 0.05), and the rSO2 was significantly decreased at T2, 3 in group P(P<0.05). The incidence of cerebral oxygen desaturation was 12% in group P, and cerebral oxygen desaturation was not detected in group S. Conclusion Sevoflurane-based anesthesia produces no effect on rSO2, however, propofol-based anesthesia can decrease rSO2 in the patients undergoing gynecological laparoscopic surgery, and sevoflurane-based anesthesia is more suitable for gynecological laparoscopic surgery. Key words: Anesthetics, inhalation; Propofol; Laparoscopy; Brain; Oxygen

Caffeic acid phenethyl ester (CAPE) protects against acute urogenital injury following pneumoperitoneum in the rat

Purpose: Our aim is to determine the biochemical and histologic changes induced in the kidneys, testis and prostate on possible ischemia and reperfusion (I/R) injury caused by pneumoperitoneum (PNP) in a rat model and to evaluate the ability of protective effects of caffeic acid phenethyl ester (CAPE). Methods: Twenty-eight adult male Wistar albino rats were randomly divided to one of three treatment groups, with seven animals in each group. Sham, laparoscopy (L), and laparoscopy plus CAPE (L + C) group were subjected to 60 min of PNP with 15 mmHg one hour before the desufflation period. Total oxidant status (TOS) and total antioxidant status (TAS) levels were determined in kidney, testis, and prostate. Kidney and testis tissues were removed to obtain a histologic score. Also, Johnsen scoring system was used for testicular tissue analysis. Results: L group had significantly higher TOS and lower TAS levels on kidney and testis compared to the other groups. In prostate biochemical analysis, there was not any difference between groups. No difference was found between groups according to kidney and testis tissues’ histologic evaluation. In evaluation of Johnsen scoring, L group showed significant lower score compared to the other two groups. Conclusions: Increased intraabdominal pressure (IAP) had an oxidative effect on kidney and testis but not on prostate in rats. Moreover, it could affect the testicular Johnsen score. All these adverse effects of IAP on both kidney and testis could be prevented by CAPE administration.

Retroperitoneal versus transperitoneal laparoscopy for simple nephrectomy

BackgroundLaparoscopic surgery is a safe and reliable option for renal procedures. Many renal procedures are performed laparoscopically through two approaches namely transperitoneal and retroperitoneal. We assessed at similar insufflation pressure alterations in hemodynamic, ventilatory and cerebral variables during retroperitoneal and transperitoneal CO2 insufflation.Patients and methodsThirty adult patients of ASA I, II were randomly allocated into two groups; retroperironeal group (Ret group, n = 15) and transperitoneal group (Tran group, n = 15) for simple laparoscopic nephrectomy under general anesthesia. After carbon dioxide insufflation, cardiovascular and respiratory variables were measured at predetermined times with the same insufflation pressure while ventilation was adjusted to maintain normal end tidal CO2. Also, cerebral blood flow velocity (CBFV) was measured by using transcranial doppler ultrasonography.ResultsMean arterial pressure and heart rate were significantly greater with transperitoneal (Tran) than retroperitoneal (Ret) group during CO2 insufflation period. While both groups required increased minute ventilation to adjust ETCO2, transperitoneal CO2 insufflation resulted in a significantly greater increase of PaCO2 than retroperitoneal group at the same insufflation pressure. Furthermore, significantly greater peak airway pressure was required with Tran group than Ret group to administer the same minute ventilation. Following CO2 decompression, all these variables did not differ significantly from preinsufflation values. Peak airway pressure also decreased after decompression; however, values still differed significantly when compared to preinsufflation in transperitoneal group. Transperitoneal CO2 insufflation resulted in a rapid increase in CBFV during the first 30 min of pneumoperitoneum and attained a plateau throughout the procedure. In contrast, CBFV increased gradually throughout the retroperitoneal CO2 insufflation and both groups returned to baseline values after desufflation.ConclusionRetroperitoneal laparoscopic approach for simple nephrectomy is not associated with greater effects on ventilatory, hemodynamic and cerebral functions compared to transperitoneal laparoscopy.

Effect of one-lung ventilation on occurrence of subcutaneous emphysema in patients undergoing retroperitoneal laparoscopic urologic surgery

Objective To investigate the effect of one-lung ventilation (OLV) on the occurrence of subcutanous emphysema during retroperitoneal laparoscopic urologic surgery (RPLUS).Methods Twenty-seven ASA Ⅰor Ⅱ patients,aged 29-64 yr,with body mass index 19-25 kg/m2,scheduled for elective RPLUS,were randomly divided into 2 groups:two-lung ventilation (TLV) group (group Ⅰ,n =15) and OLV group (group Ⅱ,n =12).In group Ⅰ,the patients were tracheal intubated and TLV was performed.In group Ⅱ,the left-sided double lumen endobronchial tube was inserted and TLV was performed,OLV on the non-operated side was performed starting from 10-15 min before pneumoperitoneum and TLV resumed at the end of pneumoperitoneum.The end-tidal CO2 partial pressure and minute ventilation volume were measured before pneumoperitoneum (T1),at 30 and 60 min of pneumoperitoneum (T2,3),and at 30 min after the end of pneumoperitoneum (T4).The CO2 absorption capacity was calculated.The degree of pneumoderma was assessed and the occurance of pneumoderma was recorded at the end of pneumoperitoneum.Results Compared with group Ⅰ,the CO2 absorption capacity was significantly reduced,and the degree and incidence of pneumoderma were significantly decreased in group Ⅱ (P ＜ 0.05).Conclusion OLV on the non-operated side can reduce the CO2 absorption capacity,decrease the degree of subcutaneous emphysema and reduce the occurrence of subcutanous emphysema during pneumoperitoneum in patients undergoing RPLUS. Key words: Subcutaneous emphysema; Pulmonary ventilation; Retroperitoneal space; Laparoscopes

Effect of right stellate ganglion block on heart rate variability in patients with carbon dioxide pneumoperitoneum

Objective To invetstigate the effects of right stellate ganglion block (SGB) on heart rate variability (HRV) in patients with carbon dioxide pneumoperitoneum.Methods Forty ASA Ⅰ or Ⅱ patients of both sexes,aged 39-75 yr,weighing 47-75 kg,undergoing elective laparoscopic cholecystectomy,were randomly divided into 2 groups ( n =20 each):control group (group C) and right SGB group (group SGB).Right SGB was performed with 1％ lidocaine 7 ml at 10 min before induction of anesthesia.The low frequency power ( LF),high frequency power (HF),total power (TP) and LF/HF ratio were recorded before SGB (baseline,To ),at 5 and 30 min of pneumoperitoneum (T1,2),at 5 min after deflation (T3) and at the end of operation (T4 ).The LF in normalized units (LFnu) and HF in normalized units (HFnu) were calculated.Results Compared with the baseline values at T0,LF,LFnu and LF/HF ratio were significantly increased at T1-4,HF was significantly decreased at T3,4,and HFnu was significantly decreased at T2-4 in group C,and HF was significantly increased at T1-4,HFnu was significantly increased at T2-4 and LF/HF ratio was significantly decreased at T1-4 in group SGB ( P ＜ 0.05 or 0.01 ).LF,LFnu and LF/HF ratio were significantly decreased at T1-4,and HF at T1-4 and HFnu at T2-4 were significantly increased in group SGB as compared with group C ( P ＜ 0.05 or 0.01 ).Conclusion Right SGB can not only inhibit the sympathetic activity induced by carbon dioxide pneumoperitoneum,but also increase the vagal tone. Key words: Stellate ganglion; Never block; Carbon dioxide; Pneumoperitoneum; Heart rate

Effect of carbon dioxide pneumoperitoneum on neuromuscular block of cisatracurium in patients undergoing laparoscopic operation

Objective To investigate the effect of carbon dioxide ( CO2 ) pneumoperitoneum on the neuromuscular block of cisatracurium in patients undergoing laparoscopic operation.Methods Sixty ASA Ⅰ or Ⅱ patients,aged 35-60 yr,with body mass index of 18-24 kg/m2,scheduled for elective hysterectomy,were randomly divided into 2 groups ( n =30 each ):pneumoperitoneum group ( group P) and control group ( group C ).Each group was further divided into 2 subgroups according to the use of the antagonist of neuromuscular block ( n =15 each):no neostigmine group ( group P0 or C0 ) and neostigmine group (group P1 or C1 ).Anesthesia was induced with fentanyl,propofol and cisatracurium and maintained with target-controlled infusion of propofol and remifentanil.Tracheal intubation was performed and the patients were mechanically ventilated.Neuromuscular function was monitored by TOF-Watch SX accelerography (Organon Co.,Organon).A train of four (TOF) stimulation of the ulnar nerve was used.When T,returned to 5％ of control height after CO2 pneumoperitoneum was established,cisatracurium 0.05 mg/kg was injected intravenously in group P.When T1 returned to 25％ of control height after the end of operation,neostigmine was injected intravenously in groups P1 andC1.The clinical duration and recovery index were recorded after CO2 pneumoperitoneum was established.Arterial blood samples were obtained immediately before induction,at 30 and 60 min of pneumoperitoneum,and at the end of operation for blood gas analysis.Results The clinical duration and recovery index were significantly longer in group P0 than in group C0,and in group P1 than in group C1 ( P ＜ 0.05).Compared with group C0,the pH value was significantly decreased and PaCO2 was significantly increased at 30 and 60 min of pneumoperitoneum,and at the end of operation in group P0 ( P ＜ 0.05).Compared with group C1,the pH value was significantly decreased and PaCO2 was significantly increased at 30 and 60 min of pneumoperitoneum,and at the end of operation in group P1 ( P ＜ 0.05).Conclusion CO2 pneumoperitoneum can strengthen the neuromuscular block induced by cisatracurium and prolong the recovery time following antangonism by neostigmine administration in patients undergoing laparoscopic operation. Key words: Atracurium; Carbon dioxide; Pneumoperitoneum; Neuromuscular blockade

Changes in noxious stimulation intensity at different periods of pneumoperitoneum in gynecological laparoscopic surgery

：Objective To evaluatethe changes in noxious stimulation intensity at different periods of pneumoperitoneum ingynecological laparoscopic surgery. Methods Forty-five ASA Ⅰ orⅡ patients, aged 25-36 yr, withbody mass index 18-23 kg/m2 , undergoing elective gynecological laparoscopic surgery, wererandomly divided into 3 groups ( n = 15 each) . In group Ⅰ , anesthesia was maintained with TCI of remifentanil (target plasma concentration4-6 ng/ml) and propofol (target plasma concentration 2 μg/ml) , and theconcentrations were ad-justed according to the changes in BP and HR to maintainhemodynamics stable. Ⅱ and Ⅲ groups received inhala-tion of isoflurane (end-tidal concentration1%-2%) and TCI of remifentanil (target plasma concentration 2-4ng/ml) . TCI ofremifentanil was then stopped at 5 min before pneumoperitoneum (group Ⅱ ) or at 5 min after theend of rapid inflation (group Ⅲ ) , and isoflurane was inhaled (end-tidal concentration 1%-2% ) tomaintain anes-thesia until the end of operation in Ⅱ and Ⅲ group. Before anesthesia (T0), 5 min before pneumoperitoneum (T1), 5 and 15 min of pneumoperitoneum (T2,3), HR and MAPwere monitored and venous blood samples were taken for determination of plasma cortisol(Cor) , norepinephrine ( NE) and epinephrine ( E) concentrations. Results HR, MAP and NEand E concentrations at T2,3 , and Cor concentrations at T3 were significantly higher thanthose at T0 ingroup Ⅱ , and in group Ⅱ than in group Ⅰ(P<0.05). HR,MAP and NE and E concentrations at T2,3 ,and Cur concentrations at T3 were significantlylower in group Ⅲ than in group Ⅱ ( P < 0.05). Conclusion Theintensity of noxious stimulation is strongest during rapid inflation among the differentperiods of pneumoperitoneum in gynecological laparoscopic surgery and the depth ofanesthesia should be regulated. Key words: Pneumoperitoneum,artificial; Laparoscopy; Stress; Gynecologic surgical procedures

Comparison of efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery

Objective To compare the efficacy of pressure-controlled ventilation and volume-controlled ventilation in children undergoing laparoscopic surgery. Methods Thirty ASA Ⅰ or Ⅱ children of both sexes,aged 12-36 months, weighing 9-15 kg, scheduled for laparoscopic surgery, were randomly divided into 2 groups (n = 15 each): pressure-controlled ventilation group (group P) and volume-controlled ventilation group (group V) . Anesthesia was induced with propofol 2-4 mg/kg, vecuronium 0.1 mg/kg and fentanyl 2 μg/kg. The children were tracheal intubated and mechanically ventilated. The maximum inspiratory pressure was adjusted to make the tidal volume (VT ) achieve 12 ml/kg in group P and the VT was set at 12 ml/kg in group V. PETCO2 was maintained at 35-45 mm Hg. MAP, HR, PETCO2 , minute ventilation and peak airway pressure were recorded immediately after intubation (T0 ) , immediately before skin incision (T1 ) , 30 min of pneumoperitoneum (T2 ) and 15 min after the end of pneumoperitoneum (T3 ) . Arterial blood samples were taken at the same time points mentioned above for blood gas analysis. Dynamic lung compliance and physiological dead space to tidal volume ratio were calculated.Results Compared with group V, PaCO2 and PETCO2 were significantly decreased and dynamic lung compliance was significantly increased at T1,2 , and minute ventilation and peak airway pressure were significantly decreased at T0-3 in group P ( P 0.05) . Conclusion Compared with volume-controlled ventilation, pressure-controlled ventilation can better improve the ventilatory efficacy, is more beneficial to gas exchange and reduces the influence of pneumoperitoneum on respiratory function in children undergoing laparoscopic surgery. Key words: Respiration,artificial; Child; Laparoscopy

Changes in renal blood flow during laparoscopic cholecystectomy

Objective To investigate the changes in renal blood flow during laparoscopic cholecystectomy.Methods Thirty-two ASA Ⅰ patients (10 male, 22 female) aged 18-64 yr, weighing 45-81 kg undergoing laparoscopic cholecystectomy were included in this study. Anesthesia was induced with midazolam, fentanyl,propofol and vecuronium and maintained with isoflurane inhalation, continuous infusion of propofol and remifentanil and intermittent iv boluses of vecuronium. The patients were intubated and mechanically ventilated. PET CO2 was maintained at 30-40 mm Hg. The probe of transesophageal echocardiography (TEE) was inserted into esophagus after tracheal intubation. The internal diameter and blood flow velocity and time integral of left renal artery and descending aorta were measured by TEE before (baseline) and at 1, 5, 10, 15, 20 and 30 min of pneumoperitoneum and 1 and 5 min after deflation. The blood flow of left renal artery (LRAF) and decending aorta (DAF) were calculated. The maximal decrease in LRAF and DAF and LRAF/DAF were analyzed. Results LRAF and DAF decreased significantly during pneumoperitoneum compared to the baseline and recovered after deflation. LRAF and DAF decreased maximally by 40% (95% confidence interval (95% CI) 31%-49% ) and 38% (95% CI 31%-44% ) at 8.9 min (95% CI 5.5-12.4 min) and 6.7 min (95% CI 4.0-9.5 min) of pneumoperitoneum respectively. There was no significant change in LRAF/DAF ratio during pneumoperitoneum. Conclusion The renal blood flow decreases at 1-30 min of pneumoperitoneum with the maximum degree of decrease about 40% at about 9 min of pneumoperitoneum and the reason is related to the decrease in the cardiac output. Key words: Cholecystectomy,laparoscopic; Renal blood flow

Physiological Responses to Different Ischemic Periods during Laparoscopic Infrarenal Aortic Cross-Clamping: Evaluation in an Experimental Animal Model

Our aim was to study the physiological repercussions of varying ischemic times during laparoscopic aortic surgery. After quarantine, laparoscopy was performed in 24 healthy pigs, which were randomly allocated to four study groups: group I (n=6), laparoscopic infrarenal abdominal aortic surgery with 30 min of crossclamping; group II (n=6), laparoscopic infrarenal abdominal aortic surgery with 60 min of cross-clamping; group III (n=6), laparoscopic infrarenal abdominal aortic surgery with 120 min of cross-clamping; group IV (n=6), 120 min pneumoperitoneum in the absence of aortic cross-clamping (control group). Hematological, biochemical, hormone, hemodynamic, and ventilatory studies were conducted during and after surgery; and a postoperative neurological evaluation was performed 10 days after surgery. Group III evidenced an increase in arterial blood pressure and heart rate that was significantly higher than those present in the other groups. Significant decreases in pH were observed in groups II and III, whereas no changes in this parameter were seen in groups I and IV. Catecholamine levels during surgery were similar in all groups (a significant [p<0.001] increase in plasmatic adrenaline and noradrenaline was seen immediately after pneumoperitoneum creation in all groups). A positive association was found between the duration of aortic clamping and hormone values at 30 and 60 min after declamping but not after 24hr. A significant increase in the renal resistive index (RRI) and a significant decrease in urine output were evidenced during laparoscopy, with significantly lower RRI values seen in group IV immediately after surgery. Thus, a synergic effect of pneumoperitoneum and aortic cross-clamping was seen in this study. These two factors together cause a hemodynamic compromise, with decreased renal perfusion and acidosis, thus negatively affecting the patient's general state during this type of surgery. Despite being well tolerated in healthy pigs, a laparoscopic aortic cross-clamping time over 60min produces significant hemodynamic, metabolic, and hormonal changes. Careful patient selection is mandatory to avoid any severe complications.

Time-related changes in hemodynamic parameters and pressure-derived indices of left ventricular function in a porcine model of prolonged pneumoperitoneum.

Advanced laparoscopic procedures require prolonged pneumoperitoneum. Increased intra-abdominal pressure causes a number of hemodynamic changes including a drop in cardiac output, but it is unclear whether there is a direct effect on cardiac contractility. In this experimental study, we sought to determine whether there is a direct impact of pneumoperitoneum on cardiac contractility. We also examined the time-related changes taking place during the insufflation period. Six young pigs were anesthetized and mechanically ventilated. Pneumoperitoneum was established by insufflating carbon dioxide to a pressure of 15 mmHg and maintained for a period of 180 min. Hemodynamic parameters including left ventricular dP/dT were invasively recorded every 15 min. All hemodynamic changes were statistically evaluated, and parameters were correlated with time. Cardiac output decreased with insufflation from a baseline of 3.37 +/- 0.34 lt/min and reached the lowest value at 165 min of pneumoperitoneum (2.86 +/- 0.30 l/min; p = 0.023). Systemic vascular resistance (SVR) significantly increased from 2236 +/- 227 dyne/s/cm(5) to a maximum of 3774 +/- 324 dyne/s/cm(5) (p = 0.005). Left ventricular dP/dT maximum did not change significantly with insufflation. The decrease in cardiac output strongly correlated with the increase in SVR (r = -0.949). Time of insufflation correlated with cardiac output (r = -0.762) and dP/dT maximum (r = -0.727). Pneumoperitoneum at 15 mmHg negatively affects cardiac output without significantly affecting cardiac contractility. A significant increase in SVR appears to be the driving event for the decreased cardiac output. Prolonged pneumoperitoneum may have an additional negative effect on hemodynamic parameters.

The changes of ventilatory parameters in laparoscopic colecystectomy.

We investigated the ventilatory changes in healthy patients without cardiopulmonary pathology during elective laparoscopic cholecystectomy in the head-up position. During surgery, intraabdominal pressure was maintained at 15 mmHg by a CO2 insufflator, and minute ventilation was controlled with a constant tidal volume and fixed respiratory rate. PETCO2 was monitored continuously and recorded every minute. Basic hemodynamic and ventilatory parameters were measured before anesthesia; after induction of anesthesia; at 5 min, 10 min and 30 min after peritoneal insufflation; and 5 min and 10 min after exsufflation. Arterial blood samples were obtained 3 times to calculate D(a-A)CO2, VD/VT, and Vco2. The latent period of PETCO2 change was 2.9 min, the ascending period was 12.6 min, and the descending period was 12.2 min. During the 71.5 min of pneumoperitoneum, V(I), VE, peak and plateau Paw increased, while Cdyn decreased significantly. Peritoneal insufflation or exsufflation also resulted in a significant change of D(a-A)CO2, D(a-A)O2, and Vco2. The anesthesiologist must be aware of both hemodynamic and ventilatory changes and must be ready to respond promptly and adequately.