Pressure injury: A non-negligible comorbidity for critical Covid-19 patients.

Dear Sir,

A multidisciplinary team from Peking Union Medical College Hospital (PUMCH) managed an ICU from Feb 4th to April 12th, in the Sino–French New City Branch of Tongji Hospital, Wuhan, a designated hospital for Covid-19. Among the 109 critically ill patients admitted to the unit, 46 (42.2%) patients (27 male, 19 female) with a median age of 66 years eventually developed various stages of pressure injury (Table 1 , Figure S1–4 in the Supplementary Appendix), despite of all the proper management.

Table 1

Characteristics of 46 Critical Covid-19 Patients with Pressure Injury.

Characteristic	Total (N = 46)	Stage I (N = 7)	Stage II (N = 33)	Stage III–IV /Unstageable (N = 6)
General characteristics
Median age (IQR) — yr	66(60–70)	68(63–72)	65(57–68)	69(66–70)
Male sex — no. (%)	27(58.7)	5(71.4)	18(54.5)	4(66.7)
Female sex — no. (%)	19(41.3)	2(28.6)	15(45.5)	2(33.3)
Median interval from onset to intubation (IQR) — days	18(12–24)	17(13–24)	18(13–21)	20(14–23)
Symptoms — no. (%)
Fever	40(87.0)	5(71.4)	29(87.9)	6(100.0)
Shortness of breath	38(82.6)	4(57.1)	29(87.9)	5(83.3)
Cough	36(78.3)	5(71.4)	26(78.8)	5(83.3)
Fatigue	20(43.5)	5(71.4)	12(36.4)	3(50.0)
Diarrhea	10(21.7)	1(14.3)	8(24.2)	1(16.7)
Sputum production	10(21.7)	1(14.3)	8(24.2)	1(16.7)
Headache	8(17.4)	2(28.6)	5(15.2)	1(16.7)
Nausea or vomiting	7(15.2)	2(28.6)	4(12.1)	1(16.7)
Myalgia	6(13.0)	1(14.3)	4(12.1)	1(16.7)
Palpitation	4(8.7)	0	4(12.1)	0
Pressure injury-related characteristics
Median interval from intubation to pressure injury event (IQR) — days	9(6–12)	9(7–12)	9(6–12)	7(6–10)
Location — no. (%)
Sacrum	41(89.1)	6(85.7)	29(87.9)	6(100.0)
Face	11(23.9)	1(14.3)	8(24.2)	2(33.3)
Heel	10(21.7)	0	6(18.2)	4(66.7)
Hip	4(8.7)	0	3(9.1)	1(16.7)
Elbow	3(6.5)	1(14.3)	2(6.1)	0
Scapula	2(4.3)	0	1(3.0)	1(16.7)
Median size (IQR) — cm2	47(22–88)	45(23–49)	46(21–68)	106(67–591)
Vasopressor support — no. (%)	35(76.1)	3(42.9)	26(78.8)	6(100.0)
Coexisting acro-ischemia — no. (%)	16(34.8)	1(14.3)	10(30.3)	5(83.3)
Intermittent haemodialysis —no. (%)	11(23.9)	0	9(27.3)	2(33.3)
Wound swab sampling — no. (%)*	23(50.0)	NA	17(51.5)	5(83.3)
Coexisting disorder — no. (%)
Hypertension	26(56.5)	6(85.7)	15(45.5)	5(83.3)
Diabetes	8(17.4)	2(28.6)	4(12.1)	2(33.3)
Cerebrovascular disease	7(15.2)	1(14.3)	4(12.1)	2(33.3)
Coronary heart disease	7(15.2)	0	6(18.2)	1(16.7)
Cancer†	5(10.9)	0	5(15.2)	0
Chronic obstructive pulmonary disease	4(8.7)	1(14.3)	2(6.1)	1(16.7)
Chronic renal disease	2(4.3)	1(14.3)	0	1(16.7)
Median laboratory values (IQR)‡
White-cell count (per mm3)	10,940(6400–15,380)	13,360(6510–17,120)	10,830(8710–14,350)	12,070(5970–21,840)
Differential count (per mm3)
Total neutrophils	9820(6270–13,660)	12,490(5540–15,650)	9690(7750–12,550)	9930(5600–19,920)
Total lymphocytes	550(410–780)	660(470–820)	560(440–750)	370(180–630)
Total monocytes	420(280–570)	370(270–780)	430(310–550)	330(140–480)
Hemoglobin (g/l)	81(69–92)	92(87–96)	78(68–90)	80(76–85)
Platelet count (per mm3)	181,000(118,300–243,500)	248,000(205,500–290,500)	180,000(119,000–230,000)	73,000(37,000–205,800)
Albumin (g/l)	23.9(21.5–26.0)	25.2(24.2–36.5)	23.0(21.2–24.8)	25.3(24.0–27.9)
Creatinine (µmol/l)	103(67–127)	96(62–126)	93(60–121)	124(114–133)
Prothrombin time (s)	16.2(15.0–17.4)	15.3(15.2–16.5)	16.2(14.9–17.7)	16.8(15.1–17.1)
Activated partial-thromboplastin time (s)	43.5(41.5–47.7)	44.7(39.5–46.0)	43.0(40.8–48.3)	45.9(44.2–47.6)
Fibrinogen (g/l)	4.3(3.2–5.9)	5.9(5.0–8.4)	4.3(3.1–5.8)	3.7(2.4–4.0)
Fibrin degradation products (mg/l)§	53.0(18.9–150.0)	14.2(6.0–19.6)	71.8(27.6–150.0)	94.5(37.3–150.0)
D-dimer (mg/l)¶	21(5.5–21.0)	3.9(2.3–4.9)	21.0(13.2–21.0)	11.1(5.2–18.9)
High-sensitivity C-reactive protein (mg/l)	75.6(43.4–140.2)	54.6(21.9–65.9)	99.9(47.0–161.4)	54.7(41.3–109.4)
Prognosis
Discharged from ICU — no. (%)	16(34.8)	3(42.9)	10(30.3)	3(50.0)
Died in ICU — no. (%)	30(65.2)	4(57.1)	23(69.7)	3(50.0)

Stage I pressure injury describes intact skin with non-blanchable erythema. No swab sample was obtained in this stage.

Any type of cancer was included in this category.

All the laboratory values were obtained from laboratory reports before medical intervention.

The reference value for the fibrin degradation products level was 150 mg/l or less.

The reference value for the D-dimer level was 21 mg/l or less.

All these 46 patients were in critical condition and received mechanical ventilation. The median interval from symptom onset to invasive ventilation was only 18 days. Forty-one (89.1%) of them had at least one of the coexisting disorders when admitted, including hypertension (56.5%), diabetes (17.4%), cerebrovascular disease (15.2%), and coronary heart disease (15.2%). Compared with the general population of Covid-19 patients in China, our patients had a higher incidence of shortness of breath (82.6%) early. Other common symptoms included fever (87.0%), cough (78.3%) and fatigue (43.5%). Gastrointestinal symptoms, such as diarrhea (21.7%) and nausea or vomiting (15.2%) were also not uncommon.

Except mechanical ventilation and coexisting disorders, other risk factors for pressure injury including malnutrition, anemia, vasopressor support, intermittent haemodialysis, and sedation were also commonly seen in our patients (Table 1). It is worth mentioning that 16 (34.8%) patients presented acro-ischemia (Figure S6–9 in the Supplementary Appendix), which is a demonstration of impaired microcirculation of the skin. As one of the indicators of poor prognosis in severe Covid-19 patients, , abnormal coagulation may also indicate the vulnerability of soft tissues.

The median interval from intubation to the presence of pressure injury was 8 days. Sacrum (89.1%) was the most common location to emerge pressure injury, as might be expected, followed by the face (23.9%) due to the prone position ventilation adopted to optimize oxygenation, heels (21.7%) and hips (8.7%). Swab samples were taken from the pressure wounds of 22 (47.8%) laboratorially confirmed cases (Figure S5 in the Supplementary Appendix). No SARS-CoV-2 virus was found on reverse transcriptase polymerase chain reaction assay.

Sixteen (34.8%) patients successfully detached from ventilators were transferred from ICU to general wards. Although the development of pressure injury is not a direct cause of mortality, it significantly increases morbidity, nursing burden and healthcare costs, and should not be neglected in the treatment of critical Covid-19 patients.

Funding

The work was supported by grants (81670444 and 81971846) from the National Natural Science Foundation of China.

Declaration of Competing Interest

The authors have no competing interests to declare.