Comparison of preformed microcuff and preformed uncuffed endotracheal tubes in pediatric cleft palate surgery-A randomized controlled trial

BACKGROUND AND AIMS

Airway management in children with oral cleft surgery carries unique challenges, concerning the proximity of the surgical site and the tracheal tube. We hypothesized that using a Microcuff oral RAE tube would reduce tube exchange and migration rate. We aimed to compare the performance of Microsoft and uncuffed oral performed tracheal tubes in children undergoing cleft palate surgeries regarding the rate of tracheal tube exchange, endobronchial intubation, and ventilatory parameters.

METHODS

One hundred children scheduled for cleft palate surgery were randomized into two groups. In the uncuffed group (n = 50), the tracheal tube was selected using the Modified Coles formula, and in the Microcuff (n = 50) group, the manufacturer's recommendations were followed. Intraoperatively, we compared the primary outcome of tube exchange using the chi-square test. The leak pressure and ventilatory parameters after head extension and mouth gag application were measured in both groups.

RESULTS

The tracheal tube exchange rate was significantly lower in the Microcuff group (0/50) than in uncuffed (19/50) preformed tubes (0 vs. 38% respectively; p <.001). The uncuffed and Microcuff tracheal tube were comparable concerning ventilation parameters and leak pressure of finally placed tubes (17.78 ± 3.95 vs. 19.26 ± 3.81 cm H2 O respectively, with a mean difference (95% CI) of -1.48 (-0.01-2.98); p-value =0.059. Cuff pressure did not vary significantly during the initial hour, and the incidence of postoperative airway morbidity between uncuffed and Microcuff tube was comparable, 5/50 (10%) versus 7/50 (14%) with risk ratio (95% CI) of 0.71(0.24-2.1), p value .49.

CONCLUSION

Microcuff oral preformed tubes performed better than uncuffed tubes regarding tube exchange during cleft palate surgery.

Effect of fourth hourly oropharyngeal suctioning on ventilator-associated events in patients requiring mechanical ventilation in intensive care units of a tertiary care center in South India: a randomized controlled trial

BACKGROUND

Mechanical ventilation (MV) is a necessary life-saving measure for critically ill patients. Ventilator-associated events (VAEs) are potentially avoidable complications associated with MV that can double the rate of death. Oral care and oropharyngeal suctioning, although neglected procedures, play a vital role in the prevention of VAE.

METHODS

A randomized controlled trial was conducted in the intensive care units to compare the effect of fourth hourly oropharyngeal suctioning with the standard oral care protocol on VAE among patients on MV. One hundred twenty mechanically ventilated patients who were freshly intubated and expected to be on ventilator support for the next 72 hours were randomly allocated to the control or intervention groups. The intervention was fourth hourly oropharyngeal suctioning along with the standard oral care procedure. The control group received standard oral care (i.e., thrice a day) and on-demand oral suctioning. On the 3rd and 7th days following the intervention, endotracheal aspirates were sent to rule out ventilator-associated pneumonia.

RESULTS

Both groups were homogenous at baseline with respect to their clinical characteristics. The intervention group had fewer VAEs (56.7%) than the control group (78.3%) which was significant at P<0.01. A significant reduction in the status of "positive culture" on ET aspirate also been observed following the 3rd day of the intervention (P<0.001).

CONCLUSIONS

One of the most basic preventive strategies is providing oral care. Oropharyngeal suctioning is also an important component of oral care that prevents microaspiration. Hence, fourth-hourly oropharyngeal suctioning with standard oral care significantly reduces the incidence of VAE.

Ultrasound-Guided Radial Arterial Catheterization in Patients With Regurgitant and Stenotic Left-Sided Cardiac Valvular Lesions

Background. The pulse characteristics of arterial circulation might affect radial artery catheterization's success rate. Therefore, we hypothesized that the success rate of radial artery catheterization would be lower in the left-sided severe stenotic valvular lesion group than severe regurgitant valvular lesion group. Methods. This prospective study was conducted among patients with left-sided cardiac valvular lesions undergoing cardiac and non-cardiac surgery. The patients with left-sided severe valvular stenosis and left-sided severe valvular regurgitation were included in the study. Radial artery cannulation was performed using an ultrasound-guided out-of-plane short-axis approach. The outcome measures were success rate, number of attempts, and cannulation time. Result. One hundred fifty-two patients were recruited for the study, and all were eligible for final analysis. The first attempt success rate was non-significantly higher in the stenotic valvular lesion group than the regurgitant group (69.7% vs 56.6%; P = .09). Furthermore, the number of attempts (median; 95% CI) was significantly higher in the regurgitant group (1; 1.2-1.43 vs 1; 1.38-1.67; P = .04). However, it may not be of clinical relevance. Moreover, the cannulation time and the number of redirections of the cannula were comparable. Heart rate was significantly higher in the regurgitant group (91.8 ± 13.9 vs 82.26 ± 15.92 beats/min; P = .00), while the incidence of atrial fibrillation was significantly higher in the stenotic lesion (P = .00). No failure was reported, and the incidence of periarterial hematoma was comparable. Conclusion. The success rate of ultrasound-guided radial arterial catheterization is comparable in left-sided stenotic valvular and regurgitant lesion groups.

Assessment of efficiency of mirror therapy in preventing phantom limb pain in patients undergoing below-knee amputation surgery-a randomized clinical trial

PURPOSE AND OBJECTIVES

Phantom limb pain (PLP) is a major cause of physical limitation and disability accounting for about 85% of amputated patients. Mirror therapy is used as a therapeutic modality for patients with phantom limb pain. Primary objective was to study the incidence of PLP at 6 months following below-knee amputation between the mirror therapy group and control group.

METHODS

Patients posted for below-knee amputation surgery were randomized into two groups. Patients allocated to group M received mirror therapy in post-operative period. Two sessions of therapy were given per day for 7 days and each session lasted for 20 min. Patients who developed pain from the missing portion of the amputated limb were considered to have PLP. All patients were followed up for six months and the time of occurrence of PLP and intensity of the pain were recorded among other demographic factors.

RESULTS

A total of 120 patients completed the study after recruitment. The demographic parameters were comparable between the two groups. Overall incidence of phantom limb pain was significantly higher in the control group (Group C) when compared to the mirror therapy (Group M) group [Group M = 7 (11.7%) vs Group C = 17 (28.3%); p = 0.022]. Intensity of PLP measured on the Numerical Rating Scale (NRS) was significantly lower at 3 months in Group M compared to Group C among patients who developed PLP [NRS - median (Inter quartile range): Group M 5 (4,5) vs Group C 6 (5,6); p 0.001].

CONCLUSION

Mirror therapy reduced the incidence of phantom limb pain when administered pre-emptively in patients undergoing amputation surgeries. The severity of the pain was also found to be lower at 3 months in patients who received pre-emptive mirror therapy.

TRIAL REGISTRATION

This prospective study was registered in the clinical trial registry of India.

TRIAL REGISTRATION NUMBER

CTRI/2020/07/026488.

Manual vs. Mechanical Ventilation in patients with Advanced Airway during CPR

Early chest compressions and rapid defibrillation are important components of cardiopulmonary resuscitation (CPR). American heart association (AHA) recommends two breaths to be delivered for every 30 compressions for an adult cardiac arrest victim. Patient with an advanced airway like endotracheal tube (ETT) should be given one breath every 6 seconds without interruptions in chest compression (10 breaths per minute). All of the modern mechanical ventilators have option to generate spontaneous breaths by the patient if the patient has spontaneous respiratory efforts. During CPR, the mechanical ventilator is fallaciously sensing the chest compressions as patient's spontaneous trigger and thereby it delivers higher respiratory rates. Avoiding excessive ventilation is one of the components of high quality CPR as excessive ventilation decreases venous return thereby decreasing the cardiac output and also it affects intra-thoracic pressure thereby adversely affects intra-arterial pressure. As modern ventilators have trigger for spontaneous breaths and they will be erroneously triggered by chest compressions, it would be prudent to use volume marked resuscitation bags or manual breathing devices (manual self-inflating resuscitation bag, Bain's circuit) for delivering breaths which can be synchronised with compression phase of CPR at RR of 10.min -1 with advanced airway in place. If any patient who is on mechanical ventilation develops cardiac arrest, patient should be disconnected from the mechanical ventilator and should be ventilated manually. Manual ventilation with aforementioned breathing devices should be used in a patient without and with advanced airway devices during CPR.

Positive end-expiratory pressure as a novel method to thwart CO2 leakage from capnothorax in robotic-assisted thoracoscopic surgery

Capnography and end tidal CO2 (EtCO2) aids the anaesthesiologist in diagnosing problems during all phases of general anaesthesia. Negative arterial to end-tidal carbon-dioxide gradient during anaesthesia has been reported in various conditions including pregnancy, infants and inadvertent exogenous addition of carbon dioxide (CO2) to the expired gas in case of thoracoscopic procedures with iatrogenic injury to lung parenchyma/bronchial tree. Thus, airway injury or intentional opening of airway as a part of surgical step can be diagnosed using a negative arterial and end tidal CO2 gradient. Higher optimal PEEP can be used as a splint across the bronchial cuff in one-lung ventilation which prevents leak from capnothorax and decrease inadvertent entry of CO2 in to the expired gases which erroneously increase arteriolar to end tidal CO2 gradient.

Intraoperative acute hematuria: Sole clue to mismatch transfusion

Hemolytic transfusion reactions (HTRs) remain one of the dreaded complications of transfusion-related morbidity and mortality. Here, we describe the diagnosis and management of acute HTR following transfusion of ABO-incompatible packed red blood cell under general anesthesia which manifested solely as acute intraoperative hematuria. A 65-year-old, diabetic male was scheduled for emergency re-explorative laparotomy in view of suspected anastomotic leak following subtotal gastrectomy. One unit of packed cell was transfused intraoperatively. Toward the end of surgery, hematuria was noted by the attending anesthesiologist, and the accidental bladder injury was ruled out by the surgeon. Transfusion of ABO-incompatible blood was spotted; direct Coombs test became positive. To mitigate the impact of incompatible blood, 1 L of 0.9% normal saline was administered. Mannitol 0.5 g/kg and furosemide 20 mg were administered every 8^th hourly, and 1 ml/kg/h of urine output was targeted. Sodium bicarbonate (7.5%) 20 meq was administered intravenously to alkalinize the urine.

Microcuff Pediatric Endotracheal Tubes: Evaluation of Cuff Sealing Pressure, Fiber-optic Assessment of Tube Tip, and Cuff Position by Ultrasonography

Background:

Use of uncuffed tubes causes lots of morbidity, and there is a surge in the use of microcuff pediatric endotracheal tubes. These tubes are not evaluated in the Indian population.

Aims:

The study aimed to evaluate the pediatric microcuff endotracheal tubes in terms of cuff sealing pressure, fiber-optic assessment of tube tip, and cuff position to assess postextubation airway morbidity.

Settings and Design:

Study design involves follow-up analytical study.

Subjects and Methods:

Thirty-four children in the age group of 2–12 years were studied. Patients with leak pressure >20 cm H₂O were exchanged with smaller size tube and excluded. Cuff pressure, fiber-optic assessment of tube tip to carina distance in neutral and flexion, ultrasound assessment of cuff position, and postextubation airway morbidity were assessed.

Statistical Analysis Used:

Parameters expressed as the median with the interquartile range. Nonparametric data were analyzed using the Wilcoxon signed-rank test.

Results:

The tracheal leak pressure was <20 cm H₂O (median 14.5 cm H₂O) in 30 children. Tube exchange was required in four patients. A complete seal was achieved in 30 patients with cuff pressures ranging from 6 to 8.25 cm of H₂O (median 8 cm of H₂O). The median caudal displacement is 0.8 cm (0.47–1.22 cm) with flexion. There was no airway-related morbidity in any of these patients.

Conclusions:

The microcuff pediatric endotracheal tubes when used according to the age-based formula had a higher tube exchange rate in our study population. However, in children in whom the tube size was appropriate, the tubes provided good sealing without increasing airway morbidity. Further studies with a larger sample size might be required to confirm the findings.

Time course of psychomotor recovery after intravenous dexmedetomidine infusion as a part of balanced anaesthetic technique: A randomised, double-blind study

Background and Aims:

Dexmedetomidine is a drug that is being widely used as an adjuvant to anaesthesia because of its unique pharmacodynamic and pharmacokinetic properties. We aimed to assess the recovery of psychomotor function from balanced anaesthesia including intravenous dexmedetomidine infusion as adjunct.

Methods:

Ninety American Society of Anesthesiologists I and II patients were randomised to group D (n = 45), to receive 1 μg/kg of dexmedetomidine loading dose over 10 min, with maintenance infusion of 0.5 μg/kg/h, and group S (n = 45), to receive an equal volume of 0.9% normal saline. Objective parameters were recovery of psychomotor function assessed by Trieger dot test (TDT), digit symbol substitution test (DSST) and intraoperative opioid requirement. the total fentanyl used intraoperatively in the two groups. Statistical analysis was performed using unpaired Student's t-test, Chi-squareor Fisher's exact test.

Results:

Psychomotor recovery assessed by TDT showed statistically significant early recovery in group D compared with group S. This was seen in the maximum distance of dots missed at 30 min, 60 min, 90 min and 120 min as well as in the average distance of dots missed at identical time points. Similarly, DSST revealed early recovery at 30 min (12.4 ± 5.3 vs. 10.4 ± 3.9 P = 0.04) postoperative interval but not at other time intervals. There was significant decrease in the intraoperative opioid requirement in group D compared with group S.

Conclusion:

The addition of dexmedetomidine to balanced anaesthetic technique significantly hastened the psychomotor recovery compared with placebo.

Competence of Intensivists in Focused Transthoracic Echocardiography in Intensive Care Unit: A Prospective Observational Study

Objectives:

Focused transthoracic echocardiography (fTTE) in critical care can be used to assess patient's volume status, ventricular contractility, right ventricle chamber size, and valvular abnormalities. The objective of the study was to assess the competency of intensivists in performing fTTE in Intensive Care Unit (ICU) patients after a brief training course by cardiologist using a specific ECHO protocol.

Methods:

One hundred and four patients in ICU were recruited for this prospective observational study over a period of 12 months. Intensivists were trained for 60 h (2 h/day for 30 days). Intensivists performed fTTE in 82 ICU patients using a specific ECHO protocol developed in consensus with cardiologists. Each patient was assessed by an intensivist and two blinded cardiologists. At the end of the study period, the competency of intensivists was compared with two cardiologists and analyzed using intraclass correlation coefficient (ICC).

Results:

There were excellent agreement between intensivists and cardiologists in terms of measuring ejection fraction (ICC estimate was 0.973–0.987), valvular function (ICC estimate for mitral valve was 0.940–0.972; ICC estimate for aortic valve was 0.872–0.940), and ICC estimate for pulmonary hypertension was 0.929–0.967. Good reliability has been found for the assessment of volume status with inferior vena cava diameter (ICC estimate for assessing hypovolemia was 0.790–0.902).

Conclusion:

Intensivists with requisite training in TTE were able to perform focused echocardiography with comparable accuracy to that of cardiologists. Further studies are required to elucidate the therapeutic implications of fTTE performed by the intensivists.

Role of Methylene Blue in the Maintenance of Postinduction Hemodynamic Status in Patients with Perforation Peritonitis: A Pilot Study

Context:

Methylene blue is an inhibitor of guanylate cyclase and hence prevents vasoplegia mediated by nitric oxide in patients with sepsis.

Aims:

This study aimed to analyze the effect of methylene blue on blood pressure maintenance following induction of anesthesia in patients presenting with peritonitis.

Subjects and Methods:

Thirty patients diagnosed to have perforation peritonitis were randomized into two groups (Group MB, Group NS). Patients in Group MB were given injection methylene blue 2 mg/kg over 20 min and patients in Group NS were given 50 ml of normal saline over 20 min, before induction. Heart rate, mean arterial pressure (MAP), cardiac output, and systemic vascular resistance (SVR) were recorded every 5 min for 1 h after infusion.

Statistical Analysis:

Hemodynamic parameters were analyzed using repeated-measures analysis of variance with Bonferroni's test. Blood gas analysis was analyzed using independent Student's t-test, and P < 0.05 was considered statistically significant.

Results:

MAP was lower at all-time points in Group NS than Group MB; however, it was statistically significant immediately, and 5 min the following induction. MAP fell from 94.8 ± 11.8 mmHg to 89.2 ± 16.0 mmHg immediate postinduction in Group MB and from 92.1 ± 9.8 mmHg to 74.1 ± 12.6 mmHg in Group NS. MAP and SVR were significantly higher in Group MB, 5 min following induction. No adverse events attributable to methylene blue were noted.

Conclusions:

Methylene blue contributes to the maintenance of postinduction hemodynamic stability in patients with perforation peritonitis.

Parallel computation of 2D Morse-Smale complexes

The Morse-Smale complex is a useful topological data structure for the analysis and visualization of scalar data. This paper describes an algorithm that processes all mesh elements of the domain in parallel to compute the Morse-Smale complex of large 2D datasets at interactive speeds. We employ a reformulation of the Morse-Smale complex using Forman’s Discrete Morse Theory and achieve scalability by computing the discrete gradient using local accesses only. We also introduce a novel approach to merge gradient paths that ensures accurate geometry of the computed complex. We demonstrate that our algorithm performs well on both multicore environments and on massively parallel architectures such as the GPU.