Increasing the Safety of Percutaneous Dilatational Tracheostomy in COVID-19 Patients

How to cite this article: Bhosale SJ, Khatib KI. Increasing the Safety of Percutaneous Dilatational Tracheostomy in COVID-19 Patients. Indian J Crit Care Med 2021;25(6):610–612.

Percutaneous dilatational tracheostomy (PDT) remains an important procedure in critically ill patients with a respiratory failure requiring prolonged mechanical ventilation with nearly 10% of the patients ending up having a tracheostomy. PDT has become the standard of care in the intensive care unit (ICU); however, there have been some concerns over it during this pandemic as it is an aerosol-generating procedure with a risk of viral transmission to the healthcare personnel.¹ As the pandemic overwhelms intensive care capacities and strains the healthcare systems, performing early tracheostomy for patients with prolonged ventilation to facilitate ventilator weaning, reducing ICU length of stay, and easing pressure on healthcare resources are ever more pertinent.²There are limited data regarding the safety and the timing of tracheostomy in COVID-19 patients, but data from previous severe acute respiratory syndrome (SARS) epidemic suggest that it can be performed safely. However, we must remember that the infectivity of coronavirus is quite high, although the mortality is low compared with the SARS (2.3 vs 11%).Recent evidence suggests that there is not much difference in the safety of open vs PDT in the ICU, but the best strategy during this pandemic is to not deviate from the current practice that the clinicians are used to.³ It is considered that PDT involves more extensive airway manipulation, bronchoscopy, serial dilations of trachea, and the need for repeated connection and disconnection from the ventilator circuit. Thus, the likelihood of aerosol generation is increased compared with an open surgical approach.⁴ There is no evidence suggesting superiority of either technique in minimizing infectivity, but the open surgical technique was preferred in the SARS outbreak.⁵ Recent experience in patients with COVID-19 infection suggests that PDT may be preferred in order to reduce aerosol production.⁶ This may help in dispelling fears associated with performing the procedure and encouraging to maintain the consistent standards.⁷Due to scarcity of data, the benefits of early tracheotomy in critically ill COVID-19 patients are unclear. According to the SARS outbreak data, the need for mechanical ventilation was associated with 46% mortality.⁴ The earlier data from United States of severe COVID-19 patients requiring mechanical ventilation reported very high mortality of nearly 88% in ventilated patients, which highlights the question whether there was any benefit in offering them tracheostomy.In a multicenter trial looking at early vs late tracheostomy, it was observed that nearly 55% of patients in the late tracheostomy group did not undergo tracheostomy. Hence, committing patients to early tracheostomy could lead to procedures in patients who may actually not need it.⁸ There is general consensus that performing tracheostomy should be avoided in patients requiring high oxygen or ventilatory requirements and also in those who need rescue ventilatory strategies such as proning.Current evidence supports early tracheostomy in a selected group of patients such as traumatic brain injury, but there is no consensus regarding the timing of tracheostomy in patients with COVID-19-associated respiratory failure.⁹ The literature also does not clearly suggest reduction in a ventilator-associated pneumonia or any mortality benefit with early tracheostomy. On the contrary, the incidence of laryngotracheal stenosis due to prolonged intubation is quite low and not significantly reduced in patients with early tracheotomy.¹⁰It has been observed that the nasopharynx and trachea have a high viral load during the acute stages of illness. In view of this, many studies suggest delaying tracheostomy for at least 2–3 weeks with an intent to balance the expected prognosis of a patient with a risk to the healthcare worker (HCW).¹¹ In their study, Chao et al. did not have any HCW affected with infection, but suggested performing tracheostomy after 3 weeks of intubation and also recommended open surgical tracheostomy over PDT, while New York Head and Neck Society suggested delaying the procedure for at least 2 weeks.¹² Angel et al. demonstrated that a modified PDT technique could be safely performed at a mean of 10.6 days with no incidence of infection transmission to HCWs.Various studies have shown most patients do not have viral shedding beyond 21 days from symptom onset, and antibody response that inhibits the infectivity may typically be detected in majority of patients by 12 days after symptom onset.¹⁴ Although PCR may detect viral RNA even up to 30 days, it does not necessarily indicate infectivity in the presence of antibodies.¹⁵ However, the value of viral load and the antibody response for judging infectivity and transmission risks need further evaluation.⁵In certain patients, it may be reasonable to consider early tracheostomy for even before 14 days, if the patient has favorable respiratory mechanics and the procedure may facilitate their recovery in terms of an improved tracheal toilet, ventilator synchrony, and need for sedation.Thus, given the high mortality rate of the disease and the lack of proven benefit of the procedure with concerns for the healthcare exposure, standard recommendation would be to consider tracheostomy after 14 days of ventilation.A preoperative testing using viral PCR for performing tracheostomy is not routinely recommended; however, it may be done in few select cases to determine the viral clearance.¹⁶PDT in COVID-19 patients can be safely performed in negative-pressure rooms with appropriate protection by the team with highest level of experience dedicated to routinely performing the procedure. It is also suggested to maintain minimal personnel and use a closed circuit and an in-line suction during ventilation.¹⁷Various measures described that are crucial to limit exposure to aerosolized secretions during the procedure are complete muscle paralysis to prevent coughing, providing FiO2 100%, and stopping mechanical ventilation just before opening the trachea.^18,19There are various measures to reduce the aerosol generation during the procedure. In this issue of IJCCM, Gunchan et al., report the results of the bedside PDT using apnea technique, with the mean apnea time of 1.83 minutes and no healthcare worker showing postprocedure symptoms of the infection.²⁰ The fact that the operators were experienced with more than 100 PDTs emphasizes the need for experienced personnel doing the procedure safely. Other method described is covering the tracheostomy site with transparent plastic sheet, which was also practiced by these authors.²¹ Generally, it is considered that the surgical tracheostomies are done above the inflated endotracheal tube (ETT) cuff, whereas in the percutaneous approach, the trachea is entered below the ETT as the tube is withdrawn, thus increasing the risk of aerosol generation.²² To mitigate this risk, few authors have suggested advancing ETT cuff well below the intended tracheotomy site and continuing apnea while incising the trachea. Another technique suggested is to insert the bronchoscope from the side of the ETT into the glottis and position it above the tracheostomy insertion site, and the ETT cuff thus will help to confirm the tracheal puncture and avoid cuff rupture, eventually reducing aerosol generation.PDT is an aerosol-generating procedure with risk to healthcare personnel; however, it can be safely performed with proper patient selection, timing of procedure, experienced operator, and using various precautionary methods that may decrease the risk of transmission.     

Synthesis and biological evaluation of delavayin-C

The synthesis of a cyclic heptapeptide, delavayin-C, cyclo(gly-tyr-tyr-tyr-pro-val-pro) is described. The structure of this compound was established on the basis of analytical IR, (1)H NMR and FAB mass spectral data. The antibacterial and antifungal activities of this peptide are also described.     

Probing Influence of Solvent on Polymorphic Transformation of Carbamazepine Using Electrospray Technology

Purpose

The objective of the current work was to investigate the influence of electrospray technology using various solvents on polymorphic transformations of carbamazepine (CBZ). CBZ was taken as a model drug for electrospray crystallization owing to its well investigated polymorphic forms.

Methods

Saturated CBZ solutions (methanol, ethanol, and 2-propanol) were electrosprayed at 20 kV to obtain CBZ crystals. The electrosprayed crystals from methanol (MCBZ), ethanol (ECBZ), and 2-propanol (PCBZ) were characterized by powder X-ray diffractometry, Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, equilibrium solubility, intrinsic dissolution rate, and stability study.

Results

MCBZ exhibited mixture of form I and II of CBZ, whereas mixture of form I, II, and III of CBZ was observed in case of ECBZ. Further, PCBZ contained mixture of form II, III, and IV of CBZ. The order in which reduction in saturation solubility and intrinsic dissolution rate was observed, it can be represented as MCBZ > PCBZ > ECBZ > unprocessed CBZ. Electrospray technology induced polymorphic transformations in CBZ crystals. The said polymorphic transformations were influenced by solvent properties along with an electric charge.

Conclusion

Thus electrospray crystallization, a continuous pharmaceutical manufacturing technique, can serve as an alternative for crystallization of API with an ability to modify their physicochemical properties.

     

Amelioration of hepatotoxicity by biocleavable aminothiol chimeras of isoniazid: Design,synthesis, kinetics and pharmacological evaluation

AIM To overcome the hazardous effects on liver caused by long-term use of antitubercular agent isoniazid(INH) by developing a novel hepatoprotective prodrug strategy by conjugating INH with aminothiols as antioxidant promoities for probable synergistic effect.METHODS INH was conjugated with N-acetyl cysteine(NAC) and N-(2)-mercaptopropionyl glycine using the SchottenBaumann reaction and with L-methionine using Boc-anhydride through a biocleavable amide linkage. Synthesized prodrugs were characterized by spectral analysis, and in vitro and in vivo release studies were carried out using HPLC. Their hepatoprotective potential was evaluated in male Wistar rats by performing liver function tests, measuring markers of oxidative stress and carrying out histopathology studies.RESULTS Prodrugs were found to be stable in acidic(pH 1.2) and basic(pH 7.4) buffers and in rat stomach homogenates, whereas they were hydrolysed significantly(59.43%-94.93%) in intestinal homogenates over a period of 6 h. Upon oral administration of prodrug NI to rats, 52.4%-61.3% INH and 47.4%-56.8% of NAC were recovered in blood in 8-10 h. Urine and faeces samples pooled over a period of 24 h exhibited 1.3%-2.5% and 0.94%-0.9% of NAC, respectively, without any presence of intact NI or INH. Prodrugs were biologically evaluated for hepatoprotective activity. All the prodrugs were effective in abating oxidative stress and re-establishing the normal hepatic physiology. The effect of prodrug of INH with NAC in restoring the levels of the enzymes superoxide dismutase and glutathione peroxidase and abrogating liver damage was noteworthy especially. CONCLUSION The findings of this investigation demonstrated that the reported prodrugs can add safety and efficacy to future clinical protocols of tuberculosis treatment.     

Impact of maternal human immunodeficiency virus infection on pregnancy and birth outcomes in Pune, India

Little is known about birth outcomes for HIV-infected women in India. We examine maternal and neonatal birth outcomes in HIV-infected women within the context of enhanced pre-natal care associated with a randomized clinical trial conducted in Pune, India. Birth outcomes of 212 HIV-infected pregnant women were compared with those of 130 HIV-uninfected pregnant women attending a government tertiary care hospital between 2002 and 2004. These women and children were participating in the Six Week Extended-Dose Nevirapine (SWEN) study. Birth outcomes and maternal morbidity data were collected at delivery. We found no differences between HIV-infected and uninfected pregnant women with respect to the proportion with elevated intrapartum blood pressure, eclampsia, oligohydramnios, intrauterine growth restriction (IUGR), preterm delivery, or caesarean section (p>0.05). HIV-infected women were more likely to have peri-partum fever (3% versus 0%, p=0.04). There were no differences in neonatal parameters such as low birth weight (LBW), infants who were small for gestational age, or those having congenital anomalies (p>0.05). Compared with infants of HIV-infected women enrolled antenatally, infants of HIV-infected women enrolled in the post-partum ward had a higher risk of pre-term delivery (20% versus 8%, p=0.02) and LBW (41% versus 22%, p=0.002). HIV-infected women in this cohort in India were not found to have significant negative birth outcomes. Antenatal care was important as those not having received any antenatal care prior to deliver were at increased risk of having a pre-term delivery or an infant with LBW. Based on these data, regular antenatal care provided to HIV-infected women can reduce risk of adverse birth outcomes for their infants.     

Choice of wound care in diabetic foot ulcer: A practical approach

Diabetic foot ulcers are the consequence of multiple factors including peripheral neuropathy,decreased blood supply,high plantar pressures,etc.,and pose a significant risk for morbidity,limb loss and mortality.The critical aspects of the wound healing mechanism and host physiological status in patients with diabetes necessitate the selection of an appropriate treatment strategy based on the complexity and type of wound.In addition to systemic antibiotics and surgical intervention,wound care is considered to be an important component of diabetic foot ulcer management.This article will focus on the use of different wound care materials in diabetic foot.From a clinical perspective,it is important to decide on the wound care material depending on the type and grade of the ulcer.This article will also provide clinicians with a simple approach to the choice of wound care materials in diabetic foot ulcer.     

The endoscopist’s role in the diagnosis and management of pancreatic cancer

Pancreatic cancer remains one of the most lethal malignancies with little improvement in survival over the past several decades in spite of advances in imaging, risk factor identification, surgical technique and chemotherapy. This disappointing outcome is mainly due to failures to make an early diagnosis. In fact, the majority of the patients present with inoperable advanced stages of the disease. Though some of the new tumor markers are promising, we are still in search of the one that has a high sensitivity and accuracy, yet is inexpensive and easy to obtain. The paradigm of management has shifted from up-front surgery followed by adjuvant chemotherapy to neoadjuvant chemoradiation followed by surgery, especially for borderline resectable cancers and even for some resectable cancers. In this article, we will critically assess the limitations of tumor markers and review the advancements in endoscopic techniques in the management of pancreatic cancer.     

Patterns of locoregional recurrence after surgery and radiotherapy or chemoradiation for rectal cancer

PURPOSE: To identify patterns of locoregional recurrence in patients treated with surgery and preoperative or postoperative radiotherapy or chemoradiation for rectal cancer. METHODS AND MATERIALS: Between November 1989 and October 2001, 554 patients with rectal cancer were treated with surgery and preoperative (85%) or postoperative (15%) radiotherapy, with 95% receiving concurrent chemotherapy. Among these patients, 46 had locoregional recurrence as the first site of failure. Computed tomography images showing the site of recurrence and radiotherapy simulation films were available for 36 of the 46 patients. Computed tomography images were used to identify the sites of recurrence and correlate the sites to radiotherapy fields in these 36 patients. RESULTS: The estimated 5-year locoregional control rate was 91%. The 36 patients in the study had locoregional recurrences at 43 sites. There were 28 (65%) in-field, 7 (16%) marginal, and 8 (19%) out-of-field recurrences. Among the in-field recurrences, 15 (56%) occurred in the low pelvis, 6 (22%) in the presacral region, 4 (15%) in the mid-pelvis, and 2 (7%) in the high pelvis. Clinical T stage, pathologic T stage, and pathologic N stage were significantly associated with the risk of in-field locoregional recurrence. The median survival after locoregional recurrence was 24.6 months. CONCLUSIONS: Patients treated with surgery and radiotherapy or chemoradiation for rectal cancer had a low risk of locoregional recurrence, with the majority of recurrences occurring within the radiation field. Because 78% of in-field recurrences occur in the low pelvic and presacral regions, consideration should be given to including the low pelvic and presacral regions in the radiotherapy boost field, especially in patients at high risk of recurrence.